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Zhou Z, Yang X, Mao A, Xu H, Lin C, Yang M, Hu W, Shao J, Xu P, Li Y, Li W, Lin R, Zhang R, Xie Q, Xu Z, Meng W. Deficiency of CAMSAP2 impairs olfaction and the morphogenesis of mitral cells. EMBO Rep 2024; 25:2861-2877. [PMID: 38839944 PMCID: PMC11239855 DOI: 10.1038/s44319-024-00166-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 04/07/2024] [Accepted: 04/22/2024] [Indexed: 06/07/2024] Open
Abstract
In developing olfactory bulb (OB), mitral cells (MCs) remodel their dendrites to establish the precise olfactory circuit, and these circuits are critical for individuals to sense odors and elicit behaviors for survival. However, how microtubules (MTs) participate in the process of dendritic remodeling remains elusive. Here, we reveal that calmodulin-regulated spectrin-associated proteins (CAMSAPs), a family of proteins that bind to the minus-end of the noncentrosomal MTs, play a crucial part in the development of MC dendrites. We observed that Camsap2 knockout (KO) males are infertile while the reproductive tract is normal. Further study showed that the infertility was due to the severe defects of mating behavior in male mice. Besides, mice with loss-of-function displayed defects in the sense of smell. Furthermore, we found that the deficiency of CAMSAP2 impairs the classical morphology of MCs, and the CAMSAP2-dependent dendritic remodeling process is responsible for this defect. Thus, our findings demonstrate that CAMSAP2 plays a vital role in regulating the development of MCs.
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Affiliation(s)
- Zhengrong Zhou
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China.
- Neuroscience Center, Department of Basic Medical Sciences, Shantou University Medical College, 515041, Shantou, Guangdong, China.
| | - Xiaojuan Yang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Aihua Mao
- Biology Department, College of Sciences, Shantou University, 515063, Shantou, China
| | - Honglin Xu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
| | - Chunnuan Lin
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Mengge Yang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Weichang Hu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Jinhui Shao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Peipei Xu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Yuejia Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Wenguang Li
- Animal Laboratory Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
| | - Ruifan Lin
- Chinese Academy of Chinese Medical Sciences, 100700, Beijing, China
| | - Rui Zhang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
| | - Qi Xie
- Chinese Academy of Chinese Medical Sciences, 100700, Beijing, China
| | - Zhiheng Xu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
- Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China
| | - Wenxiang Meng
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China.
- University of Chinese Academy of Sciences, 100049, Beijing, China.
- Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China.
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2
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Ma M, Simoes de Souza F, Futia GL, Anderson SR, Riguero J, Tollin D, Gentile-Polese A, Platt JP, Steinke K, Hiratani N, Gibson EA, Restrepo D. Sequential activity of CA1 hippocampal cells constitutes a temporal memory map for associative learning in mice. Curr Biol 2024; 34:841-854.e4. [PMID: 38325376 DOI: 10.1016/j.cub.2024.01.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 01/02/2024] [Accepted: 01/08/2024] [Indexed: 02/09/2024]
Abstract
Sequential neural dynamics encoded by time cells play a crucial role in hippocampal function. However, the role of hippocampal sequential neural dynamics in associative learning is an open question. We used two-photon Ca2+ imaging of dorsal CA1 (dCA1) neurons in the stratum pyramidale (SP) in head-fixed mice performing a go-no go associative learning task to investigate how odor valence is temporally encoded in this area of the brain. We found that SP cells responded differentially to the rewarded or unrewarded odor. The stimuli were decoded accurately from the activity of the neuronal ensemble, and accuracy increased substantially as the animal learned to differentiate the stimuli. Decoding the stimulus from individual SP cells responding differentially revealed that decision-making took place at discrete times after stimulus presentation. Lick prediction decoded from the ensemble activity of cells in dCA1 correlated linearly with lick behavior. Our findings indicate that sequential activity of SP cells in dCA1 constitutes a temporal memory map used for decision-making in associative learning. VIDEO ABSTRACT.
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Affiliation(s)
- Ming Ma
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Fabio Simoes de Souza
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Center for Mathematics, Computation and Cognition, Federal University of ABC, Sao Bernardo do Campo 09606-045, SP, Brazil
| | - Gregory L Futia
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Sean R Anderson
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Jose Riguero
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Daniel Tollin
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Arianna Gentile-Polese
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Jonathan P Platt
- Department of Neurosurgery, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kira Steinke
- Integrated Physiology Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Naoki Hiratani
- Department of Neuroscience, Washington University, St. Louis, MO 63110, USA
| | - Emily A Gibson
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Diego Restrepo
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
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3
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Niiyama T, Fujimoto S, Imai T. Microglia Are Dispensable for Developmental Dendrite Pruning of Mitral Cells in Mice. eNeuro 2023; 10:ENEURO.0323-23.2023. [PMID: 37890992 PMCID: PMC10644373 DOI: 10.1523/eneuro.0323-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 10/18/2023] [Accepted: 10/23/2023] [Indexed: 10/29/2023] Open
Abstract
During early development, neurons in the brain often form excess synaptic connections. Later, they strengthen some connections while eliminating others to build functional neuronal circuits. In the olfactory bulb, a mitral cell initially extends multiple dendrites to multiple glomeruli but eventually forms a single primary dendrite through the activity-dependent dendrite pruning process. Recent studies have reported that microglia facilitate synapse pruning during the circuit remodeling in some systems. It has remained unclear whether microglia are involved in the activity-dependent dendrite pruning in the developing brains. Here, we examined whether microglia are required for the developmental dendrite pruning of mitral cells in mice. To deplete microglia in the fetal brain, we treated mice with a colony-stimulating factor 1 receptor (CSF1R) inhibitor, PLX5622, from pregnancy. Microglia were reduced by >90% in mice treated with PLX5622. However, dendrite pruning of mitral cells was not significantly affected. Moreover, we found no significant differences in the number, density, and size of excitatory synapses formed in mitral cell dendrites. We also found no evidence for the role of microglia in the activity-dependent dendrite remodeling of layer 4 (L4) neurons in the barrel cortex. In contrast, the density of excitatory synapses (dendritic spines) in granule cells in the olfactory bulb was significantly increased in mice treated with PLX5622 at postnatal day (P) 6, suggesting a role for the regulation of dendritic spines. Our results indicate that microglia do not play a critical role in activity-dependent dendrite pruning at the neurite level during early postnatal development in mice.
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Affiliation(s)
- Tetsushi Niiyama
- Graduate School of Medical Sciences, Kyushu University, 812-8582, Fukuoka, Japan
| | - Satoshi Fujimoto
- Graduate School of Medical Sciences, Kyushu University, 812-8582, Fukuoka, Japan
| | - Takeshi Imai
- Graduate School of Medical Sciences, Kyushu University, 812-8582, Fukuoka, Japan
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4
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Ma M, Simoes de Souza F, Futia G, Anderson S, Riguero J, Tollin D, Gentile-Polese A, Platt J, Hiratani N, Gibson EA, Restrepo D. Decision-Making Time Cells in Hippocampal Dorsal CA1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.01.560382. [PMID: 37873178 PMCID: PMC10592611 DOI: 10.1101/2023.10.01.560382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Sequential neural dynamics encoded by "time cells" play a crucial role in hippocampal function. However, the role of hippocampal sequential neural dynamics in associative learning is an open question. In this manuscript, we used two-photon Ca2+ imaging of dorsal CA1 pyramidal neurons in head-fixed mice performing a go-no-go associative learning task. We found that pyramidal cells responded differentially to the rewarded or unrewarded stimuli. The stimuli were decoded accurately from the activity of the neuronal ensemble, and accuracy increased substantially as the animal learned to differentiate the stimuli. Decoding the stimulus from individual pyramidal cells that responded differentially revealed that decision-making took place at discrete times after stimulus presentation. Lick prediction decoded from the ensemble activity of cells in dCA1 correlated linearly with lick behavior indicating that sequential activity of pyramidal cells in dCA1 constitutes a temporal memory map used for decision-making in associative learning.
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Affiliation(s)
- M. Ma
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
- These authors contributed equally to this work
| | - F. Simoes de Souza
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
- Center for Mathematics, Computation and Cognition, Federal University of ABC, Sao Bernardo do Campo, SP, Brazil
- These authors contributed equally to this work
| | - G.L. Futia
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - S.R. Anderson
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - J. Riguero
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - D. Tollin
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - A. Gentile-Polese
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - J.P. Platt
- Department of Neurosurgery, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - N. Hiratani
- Department of Neuroscience, Washington University, St. Louis, MO 63110, USA
| | - E. A. Gibson
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - D. Restrepo
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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5
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Li Q, Takeuchi Y, Wang J, Gellért L, Barcsai L, Pedraza LK, Nagy AJ, Kozák G, Nakai S, Kato S, Kobayashi K, Ohsawa M, Horváth G, Kékesi G, Lőrincz ML, Devinsky O, Buzsáki G, Berényi A. Reinstating olfactory bulb-derived limbic gamma oscillations alleviates depression-like behavioral deficits in rodents. Neuron 2023; 111:2065-2075.e5. [PMID: 37164008 PMCID: PMC10321244 DOI: 10.1016/j.neuron.2023.04.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 01/31/2023] [Accepted: 04/12/2023] [Indexed: 05/12/2023]
Abstract
Although the etiology of major depressive disorder remains poorly understood, reduced gamma oscillations is an emerging biomarker. Olfactory bulbectomy, an established model of depression that reduces limbic gamma oscillations, suffers from non-specific effects of structural damage. Here, we show that transient functional suppression of olfactory bulb neurons or their piriform cortex efferents decreased gamma oscillation power in limbic areas and induced depression-like behaviors in rodents. Enhancing transmission of gamma oscillations from olfactory bulb to limbic structures by closed-loop electrical neuromodulation alleviated these behaviors. By contrast, silencing gamma transmission by anti-phase closed-loop stimulation strengthened depression-like behaviors in naive animals. These induced behaviors were neutralized by ketamine treatment that restored limbic gamma power. Taken together, our results reveal a causal link between limbic gamma oscillations and depression-like behaviors in rodents. Interfering with these endogenous rhythms can affect behaviors in rodent models of depression, suggesting that restoring gamma oscillations may alleviate depressive symptoms.
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Affiliation(s)
- Qun Li
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary; HCEMM-SZTE Magnetotherapeutics Research Group, University of Szeged, Szeged 6720, Hungary
| | - Yuichi Takeuchi
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary; Department of Neuropharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan; Department of Physiology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan; Department of Biopharmaceutical Sciences and Pharmacy, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Jiale Wang
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary; Faculty of Agriculture, University of Szeged, Szeged 6720, Hungary
| | - Levente Gellért
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary; HCEMM-SZTE Magnetotherapeutics Research Group, University of Szeged, Szeged 6720, Hungary
| | - Livia Barcsai
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary; HCEMM-SZTE Magnetotherapeutics Research Group, University of Szeged, Szeged 6720, Hungary; Neunos Inc, Boston, MA 02108, USA
| | - Lizeth K Pedraza
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary
| | - Anett J Nagy
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary; HCEMM-SZTE Magnetotherapeutics Research Group, University of Szeged, Szeged 6720, Hungary; Neunos Inc, Boston, MA 02108, USA
| | - Gábor Kozák
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary
| | - Shinya Nakai
- Department of Neuropharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Shigeki Kato
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Masahiro Ohsawa
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary; Department of Neuropharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Gyöngyi Horváth
- Department of Physiology, University of Szeged, Szeged 6720, Hungary
| | - Gabriella Kékesi
- Department of Physiology, University of Szeged, Szeged 6720, Hungary
| | - Magor L Lőrincz
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary; Department of Physiology, Anatomy and Neuroscience, Faculty of Sciences University of Szeged, Szeged 6726, Hungary; Neuroscience Division, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | - Orrin Devinsky
- Department of Neurology, NYU Langone Comprehensive Epilepsy Center, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - György Buzsáki
- Neuroscience Institute, New York University, New York, NY 10016, USA
| | - Antal Berényi
- MTA-SZTE "Momentum" Oscillatory Neuronal Networks Research Group, Department of Physiology, University of Szeged, Szeged 6720, Hungary; HCEMM-SZTE Magnetotherapeutics Research Group, University of Szeged, Szeged 6720, Hungary; Neunos Inc, Boston, MA 02108, USA; Neuroscience Institute, New York University, New York, NY 10016, USA.
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6
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Fujimoto S, Leiwe MN, Aihara S, Sakaguchi R, Muroyama Y, Kobayakawa R, Kobayakawa K, Saito T, Imai T. Activity-dependent local protection and lateral inhibition control synaptic competition in developing mitral cells in mice. Dev Cell 2023:S1534-5807(23)00237-X. [PMID: 37290446 DOI: 10.1016/j.devcel.2023.05.004] [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: 10/04/2022] [Revised: 02/20/2023] [Accepted: 05/16/2023] [Indexed: 06/10/2023]
Abstract
In developing brains, activity-dependent remodeling facilitates the formation of precise neuronal connectivity. Synaptic competition is known to facilitate synapse elimination; however, it has remained unknown how different synapses compete with one another within a post-synaptic cell. Here, we investigate how a mitral cell in the mouse olfactory bulb prunes all but one primary dendrite during the developmental remodeling process. We find that spontaneous activity generated within the olfactory bulb is essential. We show that strong glutamatergic inputs to one dendrite trigger branch-specific changes in RhoA activity to facilitate the pruning of the remaining dendrites: NMDAR-dependent local signals suppress RhoA to protect it from pruning; however, the subsequent neuronal depolarization induces neuron-wide activation of RhoA to prune non-protected dendrites. NMDAR-RhoA signals are also essential for the synaptic competition in the mouse barrel cortex. Our results demonstrate a general principle whereby activity-dependent lateral inhibition across synapses establishes a discrete receptive field of a neuron.
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Affiliation(s)
- Satoshi Fujimoto
- Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Laboratory for Sensory Circuit Formation, Riken Center for Developmental Biology, Kobe 650-0047, Japan
| | - Marcus N Leiwe
- Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Laboratory for Sensory Circuit Formation, Riken Center for Developmental Biology, Kobe 650-0047, Japan
| | - Shuhei Aihara
- Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Laboratory for Sensory Circuit Formation, Riken Center for Developmental Biology, Kobe 650-0047, Japan; Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Richi Sakaguchi
- Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Laboratory for Sensory Circuit Formation, Riken Center for Developmental Biology, Kobe 650-0047, Japan; Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Yuko Muroyama
- Department of Developmental Biology, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan
| | - Reiko Kobayakawa
- Institute of Biomedical Science, Kansai Medical University, Hirakata 573-1010, Japan
| | - Ko Kobayakawa
- Institute of Biomedical Science, Kansai Medical University, Hirakata 573-1010, Japan
| | - Tetsuichiro Saito
- Department of Developmental Biology, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan
| | - Takeshi Imai
- Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Laboratory for Sensory Circuit Formation, Riken Center for Developmental Biology, Kobe 650-0047, Japan; Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan; PRESTO and CREST, Japan Science and Technology Agency (JST), Saitama 332-0012, Japan.
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7
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Chemistry and Function of Glycosaminoglycans in the Nervous System. ADVANCES IN NEUROBIOLOGY 2023; 29:117-162. [DOI: 10.1007/978-3-031-12390-0_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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8
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Hu X, Khanzada S, Klütsch D, Calegari F, Amin H. Implementation of biohybrid olfactory bulb on a high-density CMOS-chip to reveal large-scale spatiotemporal circuit information. Biosens Bioelectron 2022; 198:113834. [PMID: 34852985 DOI: 10.1016/j.bios.2021.113834] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 10/19/2021] [Accepted: 11/22/2021] [Indexed: 12/19/2022]
Abstract
Large-scale multi-site biosensors are essential to probe the olfactory bulb (OB) circuitry for understanding the spatiotemporal dynamics of simultaneous discharge patterns. Current ex-vivo biosensing techniques are limited to recording a small set of neurons and cannot provide an adequate resolution, which hinders revealing the fast dynamic underlying the information coding mechanisms in the OB circuit. Here, we demonstrate a novel biohybrid OB-CMOS biosensing platform to decipher the cross-scale dynamics of the OB electrogenesis and quantify the distinct neuronal coding properties. The approach with 4096-microelectrodes offers a non-invasive, label-free, bioelectrical imaging to decode simultaneous firing patterns from thousands of connected neuronal ensembles in acute OB slices. The platform can measure spontaneous and drug-induced extracellular field potential activity with substantially improved spatiotemporal resolution over conventional OB-based biosensors. Also, we employ our OB-CMOS recordings to perform multidimensional analysis to instantiate specific neurophysiological metrics underlying the olfactory spatiotemporal coding that emerged from the OB interconnected layers. Our results delineate the computational implications of large-scale activity patterns in functional olfactory processing. The systematic interplay of the experimental CMOS-base platform architecture and the high-content characterization of the olfactory circuit with various computational analyses endow significant functional interrogations of the OB information processing, high-spatiotemporal connectivity mapping, and global circuit dynamics. Thus, our study can inspire the design of advanced biomimetic olfactory-based biosensors and neuromorphic approaches for diagnostic biomarkers and drug discovery applications.
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Affiliation(s)
- Xin Hu
- Biohybrid Neuroelectronics Laboratory, German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
| | - Shahrukh Khanzada
- Biohybrid Neuroelectronics Laboratory, German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
| | - Diana Klütsch
- Biohybrid Neuroelectronics Laboratory, German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
| | - Federico Calegari
- Proliferation and Differentiation of Neural Stem Cells, Center for Regenerative Therapies TU Dresden (CRTD), Dresden, Germany
| | - Hayder Amin
- Biohybrid Neuroelectronics Laboratory, German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany.
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9
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Kersen DEC, Tavoni G, Balasubramanian V. Connectivity and dynamics in the olfactory bulb. PLoS Comput Biol 2022; 18:e1009856. [PMID: 35130267 PMCID: PMC8853646 DOI: 10.1371/journal.pcbi.1009856] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 02/17/2022] [Accepted: 01/22/2022] [Indexed: 12/22/2022] Open
Abstract
Dendrodendritic interactions between excitatory mitral cells and inhibitory granule cells in the olfactory bulb create a dense interaction network, reorganizing sensory representations of odors and, consequently, perception. Large-scale computational models are needed for revealing how the collective behavior of this network emerges from its global architecture. We propose an approach where we summarize anatomical information through dendritic geometry and density distributions which we use to calculate the connection probability between mitral and granule cells, while capturing activity patterns of each cell type in the neural dynamical systems theory of Izhikevich. In this way, we generate an efficient, anatomically and physiologically realistic large-scale model of the olfactory bulb network. Our model reproduces known connectivity between sister vs. non-sister mitral cells; measured patterns of lateral inhibition; and theta, beta, and gamma oscillations. The model in turn predicts testable relationships between network structure and several functional properties, including lateral inhibition, odor pattern decorrelation, and LFP oscillation frequency. We use the model to explore the influence of cortex on the olfactory bulb, demonstrating possible mechanisms by which cortical feedback to mitral cells or granule cells can influence bulbar activity, as well as how neurogenesis can improve bulbar decorrelation without requiring cell death. Our methodology provides a tractable tool for other researchers.
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Affiliation(s)
- David E. Chen Kersen
- Computational Neuroscience Initiative, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Gaia Tavoni
- Computational Neuroscience Initiative, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Neuroscience, Washington University in St. Louis, St. Louis, Missouri, United States of America
| | - Vijay Balasubramanian
- Computational Neuroscience Initiative, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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10
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Harzsch S, Dircksen H, Hansson BS. Local olfactory interneurons provide the basis for neurochemical regionalization of olfactory glomeruli in crustaceans. J Comp Neurol 2021; 530:1399-1422. [PMID: 34843626 DOI: 10.1002/cne.25283] [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: 09/15/2021] [Revised: 11/18/2021] [Accepted: 11/23/2021] [Indexed: 11/08/2022]
Abstract
The primary olfactory centers of metazoans as diverse as arthropods and mammals consist of an array of fields of dense synaptic neuropil, the olfactory glomeruli. However, the neurochemical structure of crustacean olfactory glomeruli is largely understudied when compared to the insects. We analyzed the glomerular architecture in selected species of hermit crabs using immunohistochemistry against presynaptic proteins, the neuropeptides orcokinin, RFamide and allatostatin, and the biogenic amine serotonin. Our study reveals an unexpected level of structural complexity, unmatched by what is found in the insect olfactory glomeruli. Peptidergic and aminergic interneurons provide the structural basis for a regionalization of the crustacean glomeruli into longitudinal and concentric compartments. Our data suggest that local olfactory interneurons take a central computational role in modulating the information transfer from olfactory sensory neurons to projection neurons within the glomeruli. Furthermore, we found yet unknown neuronal elements mediating lateral inhibitory interactions across the glomerular array that may play a central role in modulating the transfer of sensory input to the output neurons through presynaptic inhibition. Our study is another step in understanding the function of crustacean olfactory glomeruli as highly complex units of local olfactory processing.
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Affiliation(s)
- Steffen Harzsch
- Department of Cytology and Evolutionary Biology, Zoological Institute and Museum, University of Greifswald, Greifswald, Germany.,Department of Evolutionary Neuroethology, Max-Planck-Institute for Chemical Ecology, Jena, Germany
| | | | - Bill S Hansson
- Department of Evolutionary Neuroethology, Max-Planck-Institute for Chemical Ecology, Jena, Germany
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11
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Environmental enrichment ameliorates high-fat diet induced olfactory deficit and decrease of parvalbumin neurons in the olfactory bulb in mice. Brain Res Bull 2021; 179:13-24. [PMID: 34848271 DOI: 10.1016/j.brainresbull.2021.11.015] [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: 06/05/2021] [Revised: 11/14/2021] [Accepted: 11/24/2021] [Indexed: 11/23/2022]
Abstract
Overweight induced by high-fat diet (HFD) represents one of the major health concerns in modern societies, which can cause lasting peripheral and central metabolic disorders in all age groups. Specifically, childhood obesity could lead to life-long impact on brain development and functioning. On the other hand, environmental enrichment (EE) has been demonstrated to be beneficial for learning and memory. Here, we explored the impact of high-fat diet on olfaction and organization of olfactory bulb cells in adolescent mice, and the effect of EE intervention thereon. Puberty mice (3-week-old) fed with HFD for 10 weeks exhibited poorer odor sensitivity and olfactory memory relative to controls consuming standard chows. The behavioral deficits were rescued in the HFD group with EE intervention. Neuroanatomically, parvalbumin (PV) interneurons in the olfactory bulb (OB) were reduced in the HFD-fed animals relative to control, while EE intervention also normalized this alteration. In contrast, cells expressing calbindin (CB), doublecortin (DCX) in the OB were not altered. Our findings suggest that PV interneurons may play a crucial role in mediating the HFD-induced olfactory deficit in adolescent mice, and can also serve a protective effect of EE against the functional deficit.
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12
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Peled N, Fuchs V, Kestenbaum EH, Oscar E, Bitran R. An Update on the Use of Exhaled Breath Analysis for the Early Detection of Lung Cancer. LUNG CANCER-TARGETS AND THERAPY 2021; 12:81-92. [PMID: 34429674 PMCID: PMC8378913 DOI: 10.2147/lctt.s320493] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 07/17/2021] [Indexed: 12/18/2022]
Abstract
Lung cancer has historically been the main responsible for cancer associated deaths. Owing to this is our current inability to screen for and diagnose early pathological findings, preventing us from a timely intervention when cure is still achievable. Over the last decade, together with the extraordinary progress in therapeutical alternatives in the field, there has been an ongoing search for a biomarker that would allow for this. Numerous technologies have been developed but their clinical application is yet to come. In this review, we provide an update on volatile organic compounds, a non-invasive method that can hold the key for detecting early metabolic pathway changes in carcinogenesis. For its compilation, web-based search engines of scientific literature such as PubMed were explored and reviewed, using articles, research, and papers deemed meaningful by authors discretion. After a brief description, we depict how this technique can complement current methods and present the value of electronic noses in the identification of the “breathprint”. Lastly, we bring some of the latest updates in the field together with the current limitations and final remarks.
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Affiliation(s)
- Nir Peled
- Shaare Zedek Medical Center, The Hebrew University, Jerusalem, Israel
| | - Vered Fuchs
- Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Emily H Kestenbaum
- Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Elron Oscar
- Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Raul Bitran
- The Legacy Heritage Oncology Center & Dr. Larry Norton Institute, Soroka Medical Center, Beer-Sheva, Israel
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13
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Aihara S, Fujimoto S, Sakaguchi R, Imai T. BMPR-2 gates activity-dependent stabilization of primary dendrites during mitral cell remodeling. Cell Rep 2021; 35:109276. [PMID: 34161760 DOI: 10.1016/j.celrep.2021.109276] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 04/28/2021] [Accepted: 05/28/2021] [Indexed: 11/29/2022] Open
Abstract
Developing neurons initially form excessive neurites and then remodel them based on molecular cues and neuronal activity. Developing mitral cells in the olfactory bulb initially extend multiple primary dendrites. They then stabilize single primary dendrites while eliminating others. However, the mechanisms underlying selective dendrite remodeling remain elusive. Using CRISPR-Cas9-based knockout screening combined with in utero electroporation, we identify BMPR-2 as a key regulator for selective dendrite stabilization. Bmpr2 knockout and its rescue experiments show that BMPR-2 inhibits LIMK without ligands and thereby permits dendrite destabilization. In contrast, the overexpression of antagonists and agonists indicates that ligand-bound BMPR-2 stabilizes dendrites, most likely by releasing LIMK. Using genetic and FRET imaging experiments, we demonstrate that free LIMK is activated by NMDARs via Rac1, facilitating dendrite stabilization through F-actin formation. Thus, the selective stabilization of primary dendrites is ensured by concomitant inputs of BMP ligands and neuronal activity.
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Affiliation(s)
- Shuhei Aihara
- Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Laboratory for Sensory Circuit Formation, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan; Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Satoshi Fujimoto
- Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Laboratory for Sensory Circuit Formation, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Richi Sakaguchi
- Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Laboratory for Sensory Circuit Formation, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan; Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Takeshi Imai
- Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Laboratory for Sensory Circuit Formation, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan; Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan.
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14
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Sensitive period for rescuing parvalbumin interneurons connectivity and social behavior deficits caused by TSC1 loss. Nat Commun 2021; 12:3653. [PMID: 34135323 PMCID: PMC8209106 DOI: 10.1038/s41467-021-23939-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 05/20/2021] [Indexed: 11/08/2022] Open
Abstract
The Mechanistic Target Of Rapamycin Complex 1 (mTORC1) pathway controls several aspects of neuronal development. Mutations in regulators of mTORC1, such as Tsc1 and Tsc2, lead to neurodevelopmental disorders associated with autism, intellectual disabilities and epilepsy. The correct development of inhibitory interneurons is crucial for functional circuits. In particular, the axonal arborisation and synapse density of parvalbumin (PV)-positive GABAergic interneurons change in the postnatal brain. How and whether mTORC1 signaling affects PV cell development is unknown. Here, we show that Tsc1 haploinsufficiency causes a premature increase in terminal axonal branching and bouton density formed by mutant PV cells, followed by a loss of perisomatic innervation in adult mice. PV cell-restricted Tsc1 haploinsufficient and knockout mice show deficits in social behavior. Finally, we identify a sensitive period during the third postnatal week during which treatment with the mTOR inhibitor Rapamycin rescues deficits in both PV cell innervation and social behavior in adult conditional haploinsufficient mice. Our findings reveal a role of mTORC1 signaling in the regulation of the developmental time course and maintenance of cortical PV cell connectivity and support a mechanistic basis for the targeted rescue of autism-related behaviors in disorders associated with deregulated mTORC1 signaling.
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15
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Lyons-Warren AM, Herman I, Hunt PJ, Arenkiel BR. A systematic-review of olfactory deficits in neurodevelopmental disorders: From mouse to human. Neurosci Biobehav Rev 2021; 125:110-121. [PMID: 33610612 PMCID: PMC8142839 DOI: 10.1016/j.neubiorev.2021.02.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 01/15/2021] [Accepted: 02/15/2021] [Indexed: 01/07/2023]
Abstract
Olfactory impairment is a common clinical motif across neurodevelopmental disorders, suggesting olfactory circuits are particularly vulnerable to disease processes and can provide insight into underlying disease mechanisms. The mouse olfactory bulb is an ideal model system to study mechanisms of neurodevelopmental disease due to its anatomical accessibility, behavioral relevance, ease of measuring circuit input and output, and the feature of adult neurogenesis. Despite the clinical relevance and experimental benefits, olfactory testing across animal models of neurodevelopmental disease has been inconsistent and non-standardized. Here we performed a systematic literature review of olfactory function testing in mouse models of neurodevelopmental disorders, and identified intriguing inconsistencies that include evidence for both increased and decreased acuity in odor detection in various mouse models of Autism Spectrum Disorder (ASD). Based on our identified gaps in the literature, we recommend direct comparison of different mouse models of ASD using standardized tests for odor detection and discrimination. This review provides a framework to guide future olfactory function testing in mouse models of neurodevelopmental diseases.
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Affiliation(s)
- Ariel M Lyons-Warren
- Baylor College of Medicine, Department of Pediatrics, Section of Pediatric Neurology and Developmental Neuroscience; Clinical Care Center, Suite 1250, 6621 Fannin St, Houston, TX 77030, United States of America;,Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX 77030 USA
| | - Isabella Herman
- Baylor College of Medicine, Department of Pediatrics, Section of Pediatric Neurology and Developmental Neuroscience; Clinical Care Center, Suite 1250, 6621 Fannin St, Houston, TX 77030, United States of America;,Baylor College of Medicine, Department of Molecular & Human Genetics; 1250 Moursund Street, Suite 1170.12, Houston TX 77030, United States of America
| | - Patrick J Hunt
- Baylor College of Medicine, Department of Molecular & Human Genetics; 1250 Moursund Street, Suite 1170.12, Houston TX 77030, United States of America
| | - Benjamin R Arenkiel
- Baylor College of Medicine, Department of Molecular & Human Genetics; 1250 Moursund Street, Suite 1170.12, Houston TX 77030, United States of America;,Baylor College of Medicine, Department of Neuroscience; 1250 Moursund Street, Suite 1170.12, Houston TX 77030, United States of America;,Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX 77030 USA.,McNair Medical Institute, Baylor College of Medicine, Houston, TX 77030
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16
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Widespread Inhibition, Antagonism, and Synergy in Mouse Olfactory Sensory Neurons In Vivo. Cell Rep 2021; 31:107814. [PMID: 32610120 DOI: 10.1016/j.celrep.2020.107814] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 05/05/2020] [Accepted: 06/03/2020] [Indexed: 12/12/2022] Open
Abstract
Sensory information is selectively or non-selectively enhanced and inhibited in the brain, but it remains unclear whether and how this occurs at the most peripheral level. Using in vivo calcium imaging of mouse olfactory bulb and olfactory epithelium in wild-type and mutant animals, we show that odors produce not only excitatory but also inhibitory responses in olfactory sensory neurons (OSNs). Heterologous assays indicate that odorants can act as agonists to some but inverse agonists to other odorant receptors. We also demonstrate that responses to odor mixtures are extensively suppressed or enhanced in OSNs. When high concentrations of odors are mixed, widespread antagonism suppresses the overall response amplitudes and density. In contrast, a mixture of low concentrations of odors often produces synergistic effects and boosts the faint odor inputs. Thus, odor responses are extensively tuned by inhibition, antagonism, and synergy at the most peripheral level, contributing to robust sensory representations.
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17
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Distinct Characteristics of Odor-evoked Calcium and Electrophysiological Signals in Mitral/Tufted Cells in the Mouse Olfactory Bulb. Neurosci Bull 2021; 37:959-972. [PMID: 33856645 PMCID: PMC8275716 DOI: 10.1007/s12264-021-00680-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 12/31/2020] [Indexed: 11/13/2022] Open
Abstract
Fiber photometry is a recently-developed method that indirectly measures neural activity by monitoring Ca2+ signals in genetically-identified neuronal populations. Although fiber photometry is widely used in neuroscience research, the relationship between the recorded Ca2+ signals and direct electrophysiological measurements of neural activity remains elusive. Here, we simultaneously recorded odor-evoked Ca2+ and electrophysiological signals [single-unit spikes and local field potentials (LFPs)] from mitral/tufted cells in the olfactory bulb of awake, head-fixed mice. Odors evoked responses in all types of signal but the response characteristics (e.g., type of response and time course) differed. The Ca2+ signal was correlated most closely with power in the β-band of the LFP. The Ca2+ signal performed slightly better at odor classification than high-γ oscillations, worse than single-unit spikes, and similarly to β oscillations. These results provide new information to help researchers select an appropriate method for monitoring neural activity under specific conditions.
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18
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Galliano E, Hahn C, Browne LP, R Villamayor P, Tufo C, Crespo A, Grubb MS. Brief Sensory Deprivation Triggers Cell Type-Specific Structural and Functional Plasticity in Olfactory Bulb Neurons. J Neurosci 2021; 41:2135-2151. [PMID: 33483429 PMCID: PMC8018761 DOI: 10.1523/jneurosci.1606-20.2020] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 11/11/2020] [Accepted: 11/17/2020] [Indexed: 02/03/2023] Open
Abstract
Can alterations in experience trigger different plastic modifications in neuronal structure and function, and if so, how do they integrate at the cellular level? To address this question, we interrogated circuitry in the mouse olfactory bulb responsible for the earliest steps in odor processing. We induced experience-dependent plasticity in mice of either sex by blocking one nostril for one day, a minimally invasive manipulation that leaves the sensory organ undamaged and is akin to the natural transient blockage suffered during common mild rhinal infections. We found that such brief sensory deprivation produced structural and functional plasticity in one highly specialized bulbar cell type: axon-bearing dopaminergic neurons in the glomerular layer. After 24 h naris occlusion, the axon initial segment (AIS) in bulbar dopaminergic neurons became significantly shorter, a structural modification that was also associated with a decrease in intrinsic excitability. These effects were specific to the AIS-positive dopaminergic subpopulation because no experience-dependent alterations in intrinsic excitability were observed in AIS-negative dopaminergic cells. Moreover, 24 h naris occlusion produced no structural changes at the AIS of bulbar excitatory neurons, mitral/tufted and external tufted cells, nor did it alter their intrinsic excitability. By targeting excitability in one specialized dopaminergic subpopulation, experience-dependent plasticity in early olfactory networks might act to fine-tune sensory processing in the face of continually fluctuating inputs.SIGNIFICANCE STATEMENT Sensory networks need to be plastic so they can adapt to changes in incoming stimuli. To see how cells in mouse olfactory circuits can change in response to sensory challenges, we blocked a nostril for just one day, a naturally relevant manipulation akin to the deprivation that occurs with a mild cold. We found that this brief deprivation induces forms of axonal and intrinsic functional plasticity in one specific olfactory bulb cell subtype: axon-bearing dopaminergic interneurons. In contrast, intrinsic properties of axon-lacking bulbar dopaminergic neurons and neighboring excitatory neurons remained unchanged. Within the same sensory circuits, specific cell types can therefore make distinct plastic changes in response to an ever-changing external landscape.
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Affiliation(s)
- Elisa Galliano
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE1 1UL, United Kingdom
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, CB2 3DY, United Kingdom
| | - Christiane Hahn
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE1 1UL, United Kingdom
| | - Lorcan P Browne
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE1 1UL, United Kingdom
| | - Paula R Villamayor
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE1 1UL, United Kingdom
| | - Candida Tufo
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE1 1UL, United Kingdom
| | - Andres Crespo
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE1 1UL, United Kingdom
| | - Matthew S Grubb
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE1 1UL, United Kingdom
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19
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Corona R, Jayakumar P, Carbajo Mata MA, Del Valle-Díaz MF, Luna-García LA, Morales T. Sexually dimorphic effects of prolactin treatment on the onset of puberty and olfactory function in mice. Gen Comp Endocrinol 2021; 301:113652. [PMID: 33122037 DOI: 10.1016/j.ygcen.2020.113652] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 10/19/2020] [Accepted: 10/22/2020] [Indexed: 11/28/2022]
Abstract
The onset of puberty is associated with the psychophysiological maturation of the adolescent to an adult capable of reproduction when olfactory signals play an important role. This period begins with the secretion of the gonadotropin-releasing hormone (GnRH) from GnRH neurons within the hypothalamus. This is regulated by kisspeptin neurons that express high levels of transmembrane prolactin receptors (PRLR) that bind to and are activated by prolactin (PRL). The elevated levels of serum PRL found during lactation, or caused by chronic PRL infusion, decreases the secretion of gonadotropins and kisspeptin and compromised the estrous cyclicity and the ovulation. In the present work, we aimed to evaluate the effects of either increased or decreased PRL circulating levels within the peripubertal murine brain by administration of PRL or treatment with cabergoline (Cab) respectively. We showed that either treatment delayed the onset of puberty in females, but not in males. This was associated with the augmentation of the PRL receptor (Prlr) mRNA expression in the arcuate nucleus and decreased Kiss1 expression in the anteroventral periventricular zone. Then, during adulthood, we assessed the activation of the mitral and granular cells of the main (MOB) and accessory olfactory bulb (AOB) by cFos immunoreactivity (ir) after the exposure to soiled bedding of the opposite sex. In the MOB, the PRL treatment promoted an increased cFos-ir of the mitral cells of males and females. In the granular cells of male of either treatment an augmented activation was observed. In the AOB, an impaired cFos-ir was observed in PRL and Cab treated females after exposure to male soiled bedding. However, in males, only Cab impaired its activation. No effects were observed in the AOB-mitral cells. In conclusion, our results demonstrate that PRL contributes to pubertal development and maturation of the MOB-AOB during the murine juvenile period in a sex-dependent way.
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Affiliation(s)
- Rebeca Corona
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Mexico.
| | - Preethi Jayakumar
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Mexico
| | | | | | | | - Teresa Morales
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Mexico
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20
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Vasilev DS, Dubrovskaya NM, Zhuravin IA, Nalivaeva NN. Developmental Profile of Brain Neprilysin Expression Correlates with Olfactory Behaviour of Rats. J Mol Neurosci 2021; 71:1772-1785. [PMID: 33433852 DOI: 10.1007/s12031-020-01786-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 12/25/2020] [Indexed: 12/26/2022]
Abstract
A neuropeptidase, neprilysin (NEP), is a major amyloid (Aβ)-degrading enzyme involved in the pathogenesis of Alzheimer's disease (AD). The olfactory system is affected early in AD with characteristic Aβ accumulation, but data on the dynamics of NEP expression in the olfactory system are absent. Our study demonstrates that NEP mRNA expression in rat olfactory bulbs (OB), entorhinal cortex (ECx), hippocampus (Hip), parietal cortex (PCx) and striatum (Str) increases during the first postnatal month being the highest in the OB and Str. By 3 months, NEP mRNA levels sharply decrease in the ECx, Hip and PCx and by 9 months in the OB, but not in the Str, which correlates with declining olfaction in aged rats tested in the food search paradigm. One-month-old rats subjected to prenatal hypoxia on E14 had lower NEP mRNA levels in the ECx, Hip and PCx (but not in the OB and Str) compared with the control offspring and demonstrated impaired olfaction in the odour preference and food search paradigms. Administration to these rats of a histone deacetylase inhibitor, sodium valproate, restored NEP expression in the ECx, Hip and PCx and improved olfaction. Our data support NEP involvement in olfactory function.
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Affiliation(s)
- Dimitrii S Vasilev
- I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry, RAS, 44 Thorez Avenue, Saint Petersburg, 194223, Russia
| | - Nadezhda M Dubrovskaya
- I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry, RAS, 44 Thorez Avenue, Saint Petersburg, 194223, Russia
| | - Igor A Zhuravin
- I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry, RAS, 44 Thorez Avenue, Saint Petersburg, 194223, Russia
| | - Natalia N Nalivaeva
- I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry, RAS, 44 Thorez Avenue, Saint Petersburg, 194223, Russia. .,School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK.
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21
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Imamura F, Ito A, LaFever BJ. Subpopulations of Projection Neurons in the Olfactory Bulb. Front Neural Circuits 2020; 14:561822. [PMID: 32982699 PMCID: PMC7485133 DOI: 10.3389/fncir.2020.561822] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 08/12/2020] [Indexed: 12/17/2022] Open
Abstract
Generation of neuronal diversity is a biological strategy widely used in the brain to process complex information. The olfactory bulb is the first relay station of olfactory information in the vertebrate central nervous system. In the olfactory bulb, axons of the olfactory sensory neurons form synapses with dendrites of projection neurons that transmit the olfactory information to the olfactory cortex. Historically, the olfactory bulb projection neurons have been classified into two populations, mitral cells and tufted cells. The somata of these cells are distinctly segregated within the layers of the olfactory bulb; the mitral cells are located in the mitral cell layer while the tufted cells are found in the external plexiform layer. Although mitral and tufted cells share many morphological, biophysical, and molecular characteristics, they differ in soma size, projection patterns of their dendrites and axons, and odor responses. In addition, tufted cells are further subclassified based on the relative depth of their somata location in the external plexiform layer. Evidence suggests that different types of tufted cells have distinct cellular properties and play different roles in olfactory information processing. Therefore, mitral and different types of tufted cells are considered as starting points for parallel pathways of olfactory information processing in the brain. Moreover, recent studies suggest that mitral cells also consist of heterogeneous subpopulations with different cellular properties despite the fact that the mitral cell layer is a single-cell layer. In this review, we first compare the morphology of projection neurons in the olfactory bulb of different vertebrate species. Next, we explore the similarities and differences among subpopulations of projection neurons in the rodent olfactory bulb. We also discuss the timing of neurogenesis as a factor for the generation of projection neuron heterogeneity in the olfactory bulb. Knowledge about the subpopulations of olfactory bulb projection neurons will contribute to a better understanding of the complex olfactory information processing in higher brain regions.
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Affiliation(s)
- Fumiaki Imamura
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA, United States
| | - Ayako Ito
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA, United States
| | - Brandon J LaFever
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA, United States
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22
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Abstract
A detailed description of olfactory system development in ants reveals that - unlike in Drosophila and as in mammals - olfactory receptors may play a role, providing new insights into the developmental evolution of complex chemosensory systems.
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Affiliation(s)
- Qichen Duan
- Department of Biology, Duke University, Durham, NC 27708, USA
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23
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Yu YH, Park DK, Yoo DY, Kim DS. Altered expression of parvalbumin immunoreactivity in rat main olfactory bulb following pilocarpine-induced status epilepticus. BMB Rep 2020. [PMID: 32317084 PMCID: PMC7196189 DOI: 10.5483/bmbrep.2020.53.4.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Epilepsy is a chronic neurological disease characterized by spontaneous recurrent seizures and caused by various factors and mechanisms. Malfunction of the olfactory bulb is frequently observed in patients with epilepsy. However, the morphological changes in the olfactory bulb during epilepsy-induced neuropathology have not been elucidated. Therefore, in the present study, we investigated the expression of parvalbumin (PV), one of the calcium-binding proteins, and morphological changes in the rat main olfactory bulb (MOB) following pilocarpine-induced status epilepticus (SE). Pilocarpine-induced SE resulted in neuronal degeneration in the external plexiform layer (EPL) and glomerular layer (GL) of the MOB. PV immunoreactivity was observed in the neuronal somas and processes in the EPL and GL of the control group. However, six hours after pilocarpine administration, PV expression was remarkably decreased in the neuronal processes compared to the somas and the average number of PV-positive interneurons was significantly decreased. Three months after pilocarpine treatment, the number of PV-positive interneurons was also significantly decreased compared to the 6 hour group in both layers. In addition, the number of NeuN-positive neurons was also significantly decreased in the EPL and GL following pilocarpine treatment. In double immunofluorescence staining for PV and MAP2, the immunoreactivity for MAP2 around the PV-positive neurons was significantly decreased three months after pilocarpine treatment. Therefore, the present findings suggest that decreases in PV-positive GABAergic interneurons and dendritic density in the MOB induced impaired calcium buffering and reciprocal synaptic transmission. Thus, these alterations may be considered key factors aggravating olfactory function in patients with epilepsy.
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Affiliation(s)
- Yeon Hee Yu
- Department of Anatomy, College of Medicine, Soonchunhyang University, Cheonan 31151, Korea
| | - Dae-Kyoon Park
- Department of Anatomy, College of Medicine, Soonchunhyang University, Cheonan 31151, Korea
| | - Dae Young Yoo
- Department of Anatomy, College of Medicine, Soonchunhyang University, Cheonan 31151, Korea
| | - Duk-Soo Kim
- Department of Anatomy, College of Medicine, Soonchunhyang University, Cheonan 31151, Korea
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Kermen F, Lal P, Faturos NG, Yaksi E. Interhemispheric connections between olfactory bulbs improve odor detection. PLoS Biol 2020; 18:e3000701. [PMID: 32310946 PMCID: PMC7192517 DOI: 10.1371/journal.pbio.3000701] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 04/30/2020] [Accepted: 04/02/2020] [Indexed: 01/06/2023] Open
Abstract
Interhemispheric connections enable interaction and integration of sensory information in bilaterian nervous systems and are thought to optimize sensory computations. However, the cellular and spatial organization of interhemispheric networks and the computational properties they mediate in vertebrates are still poorly understood. Thus, it remains unclear to what extent the connectivity between left and right brain hemispheres participates in sensory processing. Here, we show that the zebrafish olfactory bulbs (OBs) receive direct interhemispheric projections from their contralateral counterparts in addition to top-down inputs from the contralateral zebrafish homolog of olfactory cortex. The direct interhemispheric projections between the OBs reach peripheral layers of the contralateral OB and retain a precise topographic organization, which directly connects similarly tuned olfactory glomeruli across hemispheres. In contrast, interhemispheric top-down inputs consist of diffuse projections that broadly innervate the inhibitory granule cell layer. Jointly, these interhemispheric connections elicit a balance of topographically organized excitation and nontopographic inhibition on the contralateral OB and modulate odor responses. We show that the interhemispheric connections in the olfactory system enable the modulation of odor response and contribute to a small but significant improvement in the detection of a reproductive pheromone when presented together with complex olfactory cues by potentiating the response of the pheromone selective neurons. Taken together, our data show a previously unknown function for an interhemispheric connection between chemosensory maps of the olfactory system. Interhemispheric connections enable interaction and integration of sensory information in bilaterian nervous systems and are thought to optimize sensory computations. This study shows that interhemispheric olfactory connections in the zebrafish brain improve the detection of a reproductive pheromone within a noisy odor background.
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Affiliation(s)
- Florence Kermen
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Neuro-Electronics Research Flanders, Leuven, Belgium
- Department of Biology, Faculty of Natural Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- * E-mail: (FK); (EY)
| | - Pradeep Lal
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Nicholas G. Faturos
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Emre Yaksi
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Neuro-Electronics Research Flanders, Leuven, Belgium
- * E-mail: (FK); (EY)
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25
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Hunyadi A, Gaál B, Matesz C, Meszar Z, Morawski M, Reimann K, Lendvai D, Alpar A, Wéber I, Rácz É. Distribution and classification of the extracellular matrix in the olfactory bulb. Brain Struct Funct 2019; 225:321-344. [PMID: 31858237 PMCID: PMC6957564 DOI: 10.1007/s00429-019-02010-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 12/11/2019] [Indexed: 11/30/2022]
Abstract
Extracellular matrix (ECM) became an important player over the last few decades when studying the plasticity and regeneration of the central nervous system. In spite of the established role of ECM in these processes throughout the central nervous system (CNS), only few papers were published on the ECM of the olfactory system, which shows a lifelong plasticity, synaptic remodeling and postnatal neurogenesis. In the present study, we have described the localization and organization of major ECM molecules, the hyaluronan, the lecticans, tenascin-R and HAPLN1 link protein in the olfactory bulb (OB) of the rat. We detected all of these molecules in the OB showing differences in the molecular composition, staining intensity, and organization of ECM between the layers and in some cases within a single layer. One of the striking features of ECM staining pattern in the OB was that the reactions are shown dominantly in the neuropil, the PNNs were found rarely and they exhibited thin or diffuse appearance Similar organization was shown in human and mice samples. As the PNN limits the neural plasticity, its rare appearance may be related to the high degree of plasticity in the OB.
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Affiliation(s)
- Andrea Hunyadi
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary
| | - Botond Gaál
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary
| | - Clara Matesz
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary.,Division of Oral Anatomy, Faculty of Dentistry, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary.,MTA-DE Neuroscience Research Group, Nagyerdei krt. 98., Debrecen, 4032, Hungary
| | - Zoltan Meszar
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary.,MTA-DE Neuroscience Research Group, Nagyerdei krt. 98., Debrecen, 4032, Hungary
| | - Markus Morawski
- Paul-Flechsig-Institute of Brain Research, Medical Faculty, University of Leipzig, Leipzig, Germany
| | - Katja Reimann
- Paul-Flechsig-Institute of Brain Research, Medical Faculty, University of Leipzig, Leipzig, Germany
| | - David Lendvai
- Department of Anatomy, Histology, and Embryology, Semmelweis University, Budapest, 1085, Hungary
| | - Alan Alpar
- Department of Anatomy, Histology, and Embryology, Semmelweis University, Budapest, 1085, Hungary.,SE NAP Research Group of Experimental Neuroanatomy and Developmental Biology, Semmelweis University, Budapest, 1085, Hungary
| | - Ildikó Wéber
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary
| | - Éva Rácz
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary. .,MTA-DE Neuroscience Research Group, Nagyerdei krt. 98., Debrecen, 4032, Hungary.
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26
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Glutamatergic Neurons in the Piriform Cortex Influence the Activity of D1- and D2-Type Receptor-Expressing Olfactory Tubercle Neurons. J Neurosci 2019; 39:9546-9559. [PMID: 31628176 DOI: 10.1523/jneurosci.1444-19.2019] [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: 06/18/2019] [Revised: 10/08/2019] [Accepted: 10/11/2019] [Indexed: 11/21/2022] Open
Abstract
Sensory cortices process stimuli in manners essential for perception. Very little is known regarding interactions between olfactory cortices. The piriform "primary" olfactory cortex, especially its anterior division (aPCX), extends dense association fibers into the ventral striatum's olfactory tubercle (OT), yet whether this corticostriatal pathway is capable of shaping OT activity, including odor-evoked activity, is unknown. Further unresolved is the synaptic circuitry and the spatial localization of OT-innervating PCX neurons. Here we build upon standing literature to provide some answers to these questions through studies in mice of both sexes. First, we recorded the activity of OT neurons in awake mice while optically stimulating principal neurons in the aPCX and/or their association fibers in the OT while the mice were delivered odors. This uncovered evidence that PCX input indeed influences OT unit activity. We then used patch-clamp recordings and viral tracing to determine the connectivity of aPCX neurons upon OT neurons expressing dopamine receptor types D1 or D2, two prominent cell populations in the OT. These investigations uncovered that both populations of neurons receive monosynaptic inputs from aPCX glutamatergic neurons. Interestingly, this input originates largely from the ventrocaudal aPCX. These results shed light on some of the basic physiological properties of this pathway and the cell-types involved and provide a foundation for future studies to identify, among other things, whether this pathway has implications for perception.SIGNIFICANCE STATEMENT Sensory cortices interact to process stimuli in manners considered essential for perception. Very little is known regarding interactions between olfactory cortices. The present study sheds light on some of the basic physiological properties of a particular intercortical pathway in the olfactory system and provides a foundation for future studies to identify, among other things, whether this pathway has implications for perception.
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27
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Sun C, Tang K, Wu J, Xu H, Zhang W, Cao T, Zhou Y, Yu T, Li A. Leptin modulates olfactory discrimination and neural activity in the olfactory bulb. Acta Physiol (Oxf) 2019; 227:e13319. [PMID: 31144469 DOI: 10.1111/apha.13319] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/23/2019] [Accepted: 05/24/2019] [Indexed: 12/17/2022]
Abstract
AIM Leptin is an important peptide hormone that regulates food intake and plays a crucial role in modulating olfactory function. Although a few previous studies have investigated the effect of leptin on odor perception and discrimination in rodents, research on the neural basis underlying the behavioral changes is lacking. Here we study how leptin affects behavioral performance during a go/no-go task and how it modulates neural activity of mitral/tufted cells in the olfactory bulb, which plays an important role in odor information processing and representation. METHODS A go/no-go odor discrimination task was used in the behavioral test. For in vivo studies, single unit recordings, local field potential recordings and fiber photometry recordings were used. For in vitro studies, we performed patch clamp recordings in the slice of the olfactory bulb. RESULTS Behaviorally, leptin affects performance and reaction time in a difficult odor-discrimination task. Leptin decreases the spontaneous firing of single mitral/tufted cells, decreases the odor-evoked beta and high gamma local field potential response, and has bidirectional effects on the odor-evoked responses of single mitral/tufted cells. Leptin also inhibits the population calcium activity in genetically identified mitral/tufted cells and granule cells. Furthermore, in vitro slice recordings reveal that leptin inhibits mitral cell activity through direct modulation of the voltage-sensitive potassium channel. CONCLUSIONS The behavioral reduction in odor discrimination observed after leptin administration is likely due to decreased neural activity in mitral/tufted cells, caused by modulation of potassium channels in these cells.
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Affiliation(s)
- Changcheng Sun
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology Xuzhou Medical University Xuzhou China
| | - Keke Tang
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology Xuzhou Medical University Xuzhou China
| | - Jing Wu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology Xuzhou Medical University Xuzhou China
| | - Han Xu
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology Xuzhou Medical University Xuzhou China
| | - Wenfeng Zhang
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology Xuzhou Medical University Xuzhou China
| | - Tiantian Cao
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology Xuzhou Medical University Xuzhou China
| | - Yang Zhou
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology Xuzhou Medical University Xuzhou China
- The Affiliated Changzhou NO.2 People's Hospital with Nanjing Medical University Changzhou China
| | - Tian Yu
- Department of Cell and Developmental Biology University of Colorado Anschutz Medical Campus Aurora Colorado
| | - Anan Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology Xuzhou Medical University Xuzhou China
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28
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Sudden Intrabulbar Amyloid Increase Simultaneously Disrupts Olfactory Bulb Oscillations and Odor Detection. Neural Plast 2019; 2019:3424906. [PMID: 31531013 PMCID: PMC6721117 DOI: 10.1155/2019/3424906] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/11/2019] [Accepted: 06/24/2019] [Indexed: 02/07/2023] Open
Abstract
There seems to be a correlation between soluble amyloid beta protein (Aβ) accumulation in the main olfactory bulb (OB) and smell deterioration in both Alzheimer's disease (AD) patients and animal models. Moreover, this loss of smell appears to be related to alterations in neural network activity in several olfactory-related circuits, including the OB, as has been observed in anesthetized animals and brain slices. It is possible that there is a correlation between these two pathological phenomena, but a direct and simultaneous evaluation of the acute and direct effect of Aβ on OB activity while animals are actually smelling has not been performed. Thus, here, we tested the effects of acute intrabulbar injection of Aβ at a low dose (200 pmol) on the OB local field potential before and during the presence of a hidden piece of smelly food. Our results show that Aβ decreases the power of OB network activity while impairing the animal's ability to reach the hidden food. We found a strong relationship between the power of the OB oscillations and the correlation between OBs and the olfactory detection test scores. These findings provide a direct link between Aβ-induced OB network dysfunction and smell loss in rodents, which could be extrapolated to AD patients.
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29
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Holschneider DP, Givrad TK, Yang J, Stewart SB, Francis SR, Wang Z, Maarek J. Cerebral perfusion mapping during retrieval of spatial memory in rats. Behav Brain Res 2019; 375:112116. [PMID: 31377254 DOI: 10.1016/j.bbr.2019.112116] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 07/26/2019] [Accepted: 07/26/2019] [Indexed: 12/24/2022]
Abstract
Studies of brain functional activation during spatial navigation using electrophysiology and immediate-early gene responses have typically targeted a limited number of brain regions. Our study provides the first whole brain analysis of cerebral activation during retrieval of spatial memory in the freely-moving rat. Rats (LEARNERS) were trained in the Barnes maze, an allocentric spatial navigation task, while CONTROLS received passive exposure. After 19 days, functional brain mapping was performed during recall by bolus intravenous injection of [14C]-iodoantipyrine using a novel subcutaneous minipump triggered by remote activation. Regional cerebral blood flow (rCBF)-related tissue radioactivity was analyzed by statistical parametric mapping from autoradiographic images of the three-dimensionally reconstructed brains. Functional connectivity was examined between regions of the spatial navigation circuit through interregional correlation analysis. Significant rCBF increases were noted in LEARNERS compared to CONTROLS broadly across the spatial navigation circuit, including the hippocampus (anterior dorsal CA1, posterior ventral CA1-3), subiculum, thalamus, striatum, medial septum, cerebral cortex, with decreases noted in the mammillary nucleus, amygdala and insula. LEARNERS showed a significantly greater positive correlation of rCBF of the ventral hippocampus with retrosplenial, lateral orbital, parietal and primary visual cortex, and a significantly more negative correlation with the mammillary nucleus, amygdala, posterior entorhinal cortex, and anterior thalamic nucleus. The complex sensory component of the spatial navigation task was underscored by broad activation across visual, somatosensory, olfactory, auditory and vestibular circuits which was enhanced in LEARNERS. Brain mapping facilitated by an implantable minipump represents a powerful tool for evaluation of mammalian behaviors dependent on locomotion.
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Affiliation(s)
- D P Holschneider
- Dept. of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States; Dept. of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States; Viterbi School of Engineering, Dept. of Biomedical Engineering, Los Angeles, CA, 90033, United States.
| | - T K Givrad
- Viterbi School of Engineering, Dept. of Biomedical Engineering, Los Angeles, CA, 90033, United States
| | - J Yang
- Dept. of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States
| | - S B Stewart
- Dept. of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States
| | - S R Francis
- Dept. of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States
| | - Z Wang
- Dept. of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States
| | - Jmi Maarek
- Viterbi School of Engineering, Dept. of Biomedical Engineering, Los Angeles, CA, 90033, United States
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30
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Wen P, Rao X, Xu L, Zhang Z, Jia F, He X, Xu F. Cortical Organization of Centrifugal Afferents to the Olfactory Bulb: Mono- and Trans-synaptic Tracing with Recombinant Neurotropic Viral Tracers. Neurosci Bull 2019; 35:709-723. [PMID: 31069620 DOI: 10.1007/s12264-019-00385-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 09/14/2018] [Indexed: 01/14/2023] Open
Abstract
Sensory processing is strongly modulated by different brain and behavioral states, and this is based on the top-down modulation. In the olfactory system, local neural circuits in the olfactory bulb (OB) are innervated by centrifugal afferents in order to regulate the processing of olfactory information in the OB under different behavioral states. The purpose of the present study was to explore the organization of neural networks in olfactory-related cortices and modulatory nuclei that give rise to direct and indirect innervations to the glomerular layer (GL) of the OB at the whole-brain scale. Injection of different recombinant attenuated neurotropic viruses into the GL showed that it received direct inputs from each layer in the OB, centrifugal inputs from the ipsilateralanterior olfactory nucleus (AON), anterior piriform cortex (Pir), and horizontal limb of diagonal band of Broca (HDB), and various indirect inputs from bilateral cortical neurons in the AON, Pir, amygdala, entorhinal cortex, hippocampus, HDB, dorsal raphe, median raphe and locus coeruleus. These results provide a circuitry basis that will help further understand the mechanism by which olfactory information-processing in the OB is regulated.
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Affiliation(s)
- Pengjie Wen
- Center of Brain Science, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Center for Excellence in Brain Science and Intelligent Technology, Chinese Academy of Sciences, Wuhan, 430071, China
- University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaoping Rao
- Center of Brain Science, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Center for Excellence in Brain Science and Intelligent Technology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Liuying Xu
- College of Life Science, Wuhan University, Wuhan, 430072, China
| | - Zhijian Zhang
- Center of Brain Science, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Center for Excellence in Brain Science and Intelligent Technology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Fan Jia
- Center of Brain Science, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Center for Excellence in Brain Science and Intelligent Technology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Xiaobin He
- Center of Brain Science, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Center for Excellence in Brain Science and Intelligent Technology, Chinese Academy of Sciences, Wuhan, 430071, China.
| | - Fuqiang Xu
- Center of Brain Science, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Center for Excellence in Brain Science and Intelligent Technology, Chinese Academy of Sciences, Wuhan, 430071, China.
- Divisions of Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Wuhan, 430074, China.
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31
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Li S, Li W, Wu X, Li J, Yang J, Tu C, Ye X, Ling S. Olfactory deficit is associated with mitral cell dysfunction in the olfactory bulb of P301S tau transgenic mice. Brain Res Bull 2019; 148:34-45. [PMID: 30902575 DOI: 10.1016/j.brainresbull.2019.03.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 03/09/2019] [Accepted: 03/14/2019] [Indexed: 01/24/2023]
Abstract
Neurofibrillary tangles consisting of hyperphosphorylated tau (P-tau) are the neuropathological hallmark of Alzheimer's disease (AD), and olfaction disorder is an early symptom of AD. However, the link between P-tau aggregation and olfaction disorder remains unclear. In this study, the expression of P-tau in the olfactory bulb (OB), particularly in the mitral cell layer (MCL), external plexiform layer (EPL), and granule cell layer (GCL), of AD patients was found to be significantly higher than that in the OB of normal aging subjects, which suggested that these layers in the OB were susceptible to P-tau. The P301S tau transgenic mice (P301S mice) exhibit AD-like features, which can be characterized by olfactory dysfunction that precedes cognitive disorder. Importantly, the excessive P-tau expression in the OB of P301S mice, particularly in MCs, was associated with MC loss at 9 months of age, and decreased MC firing activities started to be observed at 2 months of age. Our results revealed that MCs might contribute to olfactory dysfunction in P301S mice. Furthermore, we described an aberrant dendro-dendritic synaptic structure between granule cells (GCs) and MCs and abnormal gamma oscillations in the EPL of the OB, and these findings indicated that P-tau might disrupt the regulation of MCs by GCs in P301S mice starting at 5 months of age. These data showed that the reduction in the MC firing frequency at 2 months of age might not be caused by GC suppression. Based on these findings, we speculated that MCs are a putative target for the treatment of P-tau-induced early olfactory dysfunction, and thus, an exploration of the specific causes and mechanisms of MC functional changes in P301S mice is crucial.
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Affiliation(s)
- Shanshan Li
- Institute of Neuroscience and Anatomy, School of Medicine, Zhejiang University, Hangzhou, China
| | - Weiyun Li
- Institute of Neuroscience and Anatomy, School of Medicine, Zhejiang University, Hangzhou, China; Department of Clinical Medicine, Zhejiang University City College, Hangzhou, China
| | - Xuewei Wu
- Institute of Neuroscience and Anatomy, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jing Li
- Institute of Neuroscience and Anatomy, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jing Yang
- Institute of Neuroscience and Anatomy, School of Medicine, Zhejiang University, Hangzhou, China
| | - Chunlong Tu
- Biosensor National Special Laboratory, Key Laboratory of BME of the Ministry of Education, Zhejiang University, Hangzhou, China
| | - Xuesong Ye
- Biosensor National Special Laboratory, Key Laboratory of BME of the Ministry of Education, Zhejiang University, Hangzhou, China.
| | - Shucai Ling
- Institute of Neuroscience and Anatomy, School of Medicine, Zhejiang University, Hangzhou, China.
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32
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Beiersdorfer A, Scheller A, Kirchhoff F, Lohr C. Panglial gap junctions between astrocytes and olfactory ensheathing cells mediate transmission of Ca 2+ transients and neurovascular coupling. Glia 2019; 67:1385-1400. [PMID: 30883940 DOI: 10.1002/glia.23613] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 02/22/2019] [Accepted: 02/25/2019] [Indexed: 12/13/2022]
Abstract
Astrocytes are arranged in highly organized gap junction-coupled networks, communicating via the propagation of Ca2+ waves. Astrocytes are gap junction-coupled not only to neighboring astrocytes, but also to oligodendrocytes, forming so-called panglial syncytia. It is not known, however, whether glial cells in panglial syncytia transmit information using Ca2+ signaling. We used confocal Ca2+ imaging to study intercellular communication between astrocytes and olfactory ensheathing glial cells (OECs) in in-toto preparations of the mouse olfactory bulb. Our results demonstrate that Ca2+ transients in juxtaglomerular astrocytes, evoked by local photolysis of "caged" ATP and "caged" tACPD, led to subsequent Ca2+ responses in OECs. This transmission of Ca2+ responses from astrocytes to OECs persisted in the presence of neuronal inhibition, but was absent when gap junctional coupling was suppressed with carbenoxolone. When Ca2+ transients were directly evoked in OECs by puff application of DHPG, they resulted in delayed Ca2+ responses in juxtaglomerular astrocytes, indicating that panglial transmission of Ca2+ signals occurred in a bidirectional manner. In addition, panglial transmission of Ca2+ signals from astrocytes to OECs resulted in vasoconstriction of OEC-associated blood vessels in the olfactory nerve layer. Our results demonstrate functional transmission of Ca2+ signals between different classes of glial cells within gap junction-coupled panglial networks and the resulting regulation of blood vessel diameter in the olfactory bulb.
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Affiliation(s)
| | - Anja Scheller
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| | - Frank Kirchhoff
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| | - Christian Lohr
- Division of Neurophysiology, University of Hamburg, Hamburg, Germany
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33
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Paul JR, Davis JA, Goode LK, Becker BK, Fusilier A, Meador-Woodruff A, Gamble KL. Circadian regulation of membrane physiology in neural oscillators throughout the brain. Eur J Neurosci 2019; 51:109-138. [PMID: 30633846 DOI: 10.1111/ejn.14343] [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: 07/25/2018] [Revised: 12/19/2018] [Accepted: 12/21/2018] [Indexed: 12/21/2022]
Abstract
Twenty-four-hour rhythmicity in physiology and behavior are driven by changes in neurophysiological activity that vary across the light-dark and rest-activity cycle. Although this neural code is most prominent in neurons of the primary circadian pacemaker in the suprachiasmatic nucleus (SCN) of the hypothalamus, there are many other regions in the brain where region-specific function and behavioral rhythmicity may be encoded by changes in electrical properties of those neurons. In this review, we explore the existing evidence for molecular clocks and/or neurophysiological rhythms (i.e., 24 hr) in brain regions outside the SCN. In addition, we highlight the brain regions that are ripe for future investigation into the critical role of circadian rhythmicity for local oscillators. For example, the cerebellum expresses rhythmicity in over 2,000 gene transcripts, and yet we know very little about how circadian regulation drives 24-hr changes in the neural coding responsible for motor coordination. Finally, we conclude with a discussion of how our understanding of circadian regulation of electrical properties may yield insight into disease mechanisms which may lead to novel chronotherapeutic strategies in the future.
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Affiliation(s)
- Jodi R Paul
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jennifer A Davis
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Lacy K Goode
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Bryan K Becker
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Allison Fusilier
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Aidan Meador-Woodruff
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Karen L Gamble
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
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34
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Sakaguchi R, Leiwe MN, Imai T. Bright multicolor labeling of neuronal circuits with fluorescent proteins and chemical tags. eLife 2018; 7:e40350. [PMID: 30454553 PMCID: PMC6245733 DOI: 10.7554/elife.40350] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 10/24/2018] [Indexed: 11/13/2022] Open
Abstract
The stochastic multicolor labeling method 'Brainbow' is a powerful strategy to label multiple neurons differentially with fluorescent proteins; however, the fluorescence levels provided by the original attempts to use this strategy were inadequate. In the present study, we developed a stochastic multicolor labeling method with enhanced expression levels that uses a tetracycline-operator system (Tetbow). We optimized Tetbow for either plasmid or virus vector-mediated multicolor labeling. When combined with tissue clearing, Tetbow was powerful enough to visualize the three-dimensional architecture of individual neurons. Using Tetbow, we were able to visualize the axonal projection patterns of individual mitral/tufted cells along several millimeters in the mouse olfactory system. We also developed a Tetbow system with chemical tags, in which genetically encoded chemical tags were labeled with synthetic fluorophores. This was useful in expanding the repertoire of the fluorescence labels and the applications of the Tetbow system. Together, these new tools facilitate light-microscopy-based neuronal tracing at both a large scale and a high resolution.
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Affiliation(s)
- Richi Sakaguchi
- Graduate School of Medical SciencesKyushu UniversityFukuokaJapan
- Graduate School of BiostudiesKyoto UniversityKyotoJapan
- Laboratory for Sensory Circuit FormationRIKEN Center for Developmental BiologyKobeJapan
| | - Marcus N Leiwe
- Graduate School of Medical SciencesKyushu UniversityFukuokaJapan
- Laboratory for Sensory Circuit FormationRIKEN Center for Developmental BiologyKobeJapan
| | - Takeshi Imai
- Graduate School of Medical SciencesKyushu UniversityFukuokaJapan
- Graduate School of BiostudiesKyoto UniversityKyotoJapan
- Laboratory for Sensory Circuit FormationRIKEN Center for Developmental BiologyKobeJapan
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35
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Imam A, Bhagwandin A, Ajao MS, Spocter MA, Ihunwo AO, Manger PR. The brain of the tree pangolin (Manis tricuspis
). II. The olfactory system. J Comp Neurol 2018; 526:2548-2569. [DOI: 10.1002/cne.24510] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 07/27/2018] [Accepted: 07/27/2018] [Indexed: 12/25/2022]
Affiliation(s)
- Aminu Imam
- Faculty of Health Sciences, University of the Witwatersrand; School of Anatomical Sciences; Republic of South Africa
- Department of Anatomy, Faculty of Basic Medical Sciences; College of Health Sciences, University of Ilorin; Ilorin Nigeria
| | - Adhil Bhagwandin
- Faculty of Health Sciences, University of the Witwatersrand; School of Anatomical Sciences; Republic of South Africa
| | - Moyosore S. Ajao
- Department of Anatomy, Faculty of Basic Medical Sciences; College of Health Sciences, University of Ilorin; Ilorin Nigeria
| | - Muhammed A. Spocter
- Faculty of Health Sciences, University of the Witwatersrand; School of Anatomical Sciences; Republic of South Africa
- Department of Anatomy; Des Moines University; Iowa
| | - Amadi O. Ihunwo
- Faculty of Health Sciences, University of the Witwatersrand; School of Anatomical Sciences; Republic of South Africa
| | - Paul R. Manger
- Faculty of Health Sciences, University of the Witwatersrand; School of Anatomical Sciences; Republic of South Africa
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36
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Sinakevitch I, Bjorklund GR, Newbern JM, Gerkin RC, Smith BH. Comparative study of chemical neuroanatomy of the olfactory neuropil in mouse, honey bee, and human. BIOLOGICAL CYBERNETICS 2018; 112:127-140. [PMID: 28852854 PMCID: PMC5832527 DOI: 10.1007/s00422-017-0728-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Accepted: 08/14/2017] [Indexed: 06/07/2023]
Abstract
Despite divergent evolutionary origins, the organization of olfactory systems is remarkably similar across phyla. In both insects and mammals, sensory input from receptor cells is initially processed in synaptically dense regions of neuropil called glomeruli, where neural activity is shaped by local inhibition and centrifugal neuromodulation prior to being sent to higher-order brain areas by projection neurons. Here we review both similarities and several key differences in the neuroanatomy of the olfactory system in honey bees, mice, and humans, using a combination of literature review and new primary data. We have focused on the chemical identity and the innervation patterns of neuromodulatory inputs in the primary olfactory system. Our findings show that serotonergic fibers are similarly distributed across glomeruli in all three species. Octopaminergic/tyraminergic fibers in the honey bee also have a similar distribution, and possibly a similar function, to noradrenergic fibers in the mammalian OBs. However, preliminary evidence suggests that human OB may be relatively less organized than its counterparts in honey bee and mouse.
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Affiliation(s)
- Irina Sinakevitch
- School of Life Sciences, Arizona State University, PO Box 874501, Tempe, AZ, 85287-4501, USA.
| | - George R Bjorklund
- School of Life Sciences, Arizona State University, PO Box 874501, Tempe, AZ, 85287-4501, USA
| | - Jason M Newbern
- School of Life Sciences, Arizona State University, PO Box 874501, Tempe, AZ, 85287-4501, USA
| | - Richard C Gerkin
- School of Life Sciences, Arizona State University, PO Box 874501, Tempe, AZ, 85287-4501, USA
| | - Brian H Smith
- School of Life Sciences, Arizona State University, PO Box 874501, Tempe, AZ, 85287-4501, USA.
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37
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Prep1 Deficiency Affects Olfactory Perception and Feeding Behavior by Impairing BDNF-TrkB Mediated Neurotrophic Signaling. Mol Neurobiol 2018; 55:6801-6815. [PMID: 29349576 PMCID: PMC6061220 DOI: 10.1007/s12035-018-0873-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 01/07/2018] [Indexed: 11/01/2022]
Abstract
Prep1 is a homeodomain transcription factor which has an important role in hindbrain development. Prep1 expression is also kept in adult mouse brain and in particular within the olfactory bulbs. Moreover, many Prep1 neurons co-localize with Calbindin-positive periglomerular interneurons in olfactory glomerular layer. However, Prep1 function in this brain region is still unknown. In this study, we show that Prep1 hypomorphic heterozygous (Prep1i/+) mice express low levels of protein and feature a 30% reduction of olfactory bulb area, compared to WT mice. In addition, Prep1i/+ mice olfactory bulb histological analysis indicated a 20% lower cytochrome C oxidase activity within the glomerular layer, accompanied by a reduced number of periglomerular interneurons, compared to the WT littermates. Consistently, olfactory perception test highlighted that Prep1 hypomorphic heterozygous mice display a scant ability to distinguish odors, which significantly impacts on feeding behavior, as Prep1i/+ mice revealed a reduced preference for high-fat food. Analysis of BDNF signaling, which represents the main molecular mediator of olfactory plasticity, showed that Prep1i/+ mouse olfactory bulbs feature a 30% reduction of TrkB receptor levels and a decreased activation of ERK1/2. Similarly, overexpression of Prep1 in mouse neuronal cells (N2A) caused an increase of TrkB expression levels, BDNF-induced ERK phosphorylation, and cell viability, compared to control cells. We conclude that Prep1 deficiency alters olfactory morpho-functional integrity and olfaction-mediated eating behavior by affecting BDNF-TrkB signaling. Prep1 could, therefore, play a crucial role in behavioral dysfunctions associated to impaired responsiveness to BDNF.
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38
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Iwata R, Kiyonari H, Imai T. Mechanosensory-Based Phase Coding of Odor Identity in the Olfactory Bulb. Neuron 2017; 96:1139-1152.e7. [PMID: 29216451 DOI: 10.1016/j.neuron.2017.11.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 10/13/2017] [Accepted: 11/06/2017] [Indexed: 11/17/2022]
Abstract
Mitral and tufted (M/T) cells in the olfactory bulb produce rich temporal patterns of activity in response to different odors. However, it remains unknown how these temporal patterns are generated and how they are utilized in olfaction. Here we show that temporal patterning effectively discriminates between the two sensory modalities detected by olfactory sensory neurons (OSNs): odor and airflow-driven mechanical signals. Sniff-induced mechanosensation generates glomerulus-specific oscillatory activity in M/T cells, whose phase was invariant across airflow speed. In contrast, odor stimulation caused phase shifts (phase coding). We also found that odor-evoked phase shifts are concentration invariant and stable across multiple sniff cycles, contrary to the labile nature of rate coding. The loss of oscillatory mechanosensation impaired the precision and stability of phase coding, demonstrating its role in olfaction. We propose that phase, not rate, coding is a robust encoding strategy of odor identity and is ensured by airflow-induced mechanosensation in OSNs.
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Affiliation(s)
- Ryo Iwata
- Laboratory for Sensory Circuit Formation, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Hiroshi Kiyonari
- Animal Resource Development Unit and Genetic Engineering Team, RIKEN Center for Life Science Technologies, Kobe 650-0047, Japan
| | - Takeshi Imai
- Laboratory for Sensory Circuit Formation, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan; PRESTO, Japan Science and Technology Agency (JST), Saitama 332-0012, Japan; Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan; Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
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39
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Lack of Pattern Separation in Sensory Inputs to the Olfactory Bulb during Perceptual Learning. eNeuro 2017; 4:eN-NWR-0287-17. [PMID: 28955724 PMCID: PMC5615249 DOI: 10.1523/eneuro.0287-17.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 09/04/2017] [Accepted: 09/11/2017] [Indexed: 11/21/2022] Open
Abstract
Recent studies revealed changes in odor representations in the olfactory bulb during active olfactory learning (Chu et al., 2016; Yamada et al., 2017). Specifically, mitral cell ensemble responses to very similar odorant mixtures sparsened and became more distinguishable as mice learned to discriminate the odorants over days (Chu et al., 2016). In this study, we explored whether changes in the sensory inputs to the bulb underlie the observed changes in mitral cell responses. Using two-photon calcium imaging to monitor the odor responses of the olfactory sensory neuron (OSN) axon terminals in the glomeruli of the olfactory bulb during a discrimination task, we found that OSN inputs to the bulb are stable during discrimination learning. During one week of training to discriminate between very similar odorant mixtures in a Go/No-go task, OSN responses did not show significant sparsening, and the responses to the trained similar odorants did not diverge throughout training. These results suggest that the adaptive changes of mitral cell responses during perceptual learning are ensured by mechanisms downstream of OSN input, possibly in local circuits within olfactory bulb.
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40
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Ringer C, Weihe E, Schütz B. SOD1G93A Mutant Mice Develop a Neuroinflammation-Independent Dendropathy in Excitatory Neuronal Subsets of the Olfactory Bulb and Retina. J Neuropathol Exp Neurol 2017; 76:769-778. [PMID: 28859334 DOI: 10.1093/jnen/nlx057] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Nonmotor neuron-related pathology is a feature of amyotrophic lateral sclerosis (ALS), both in patients and in animal models. There is emerging evidence that sensory systems (olfaction and vision) are affected in humans. Here, we asked whether such sensory neuropathology is recapitulated in the superoxide dismutase 1 (SOD1G93A) mouse model of ALS. Neuronal vacuolization in olfaction and vision pathways was assessed in tissue sections from presymptomatic and symptomatic disease stages, and compared to wild type. In both, the olfactory bulb and retina, vacuolization started around postnatal day 60, and vacuole sizes increased until disease end-stage. Notably, vacuolization was largely restricted to the external plexiform layer of the olfactory bulb and to the inner plexiform layer of the retina. In both layers, hSOD1-immunoreactive vacuoles localized to dendrites of excitatory neurons. Downstream olfaction and vision pathway fiber tracts and relay stations did not display obvious vacuolization. Finally, on a morphological level, there was no evidence for an activation of astrocytes and microglia in the 2 affected areas. Thus, we identified a new pathology hallmark in SOD1G93A ALS mice: a glutamatergic sensory neuron dendropathy restricted to olfactory bulb mitral cells and retinal ganglionic cells.
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Affiliation(s)
- Cornelia Ringer
- Department of Molecular Neurosciences, Institute of Anatomy and Cell Biology, Philipps-University, Marburg, Germany
| | - Eberhard Weihe
- Department of Molecular Neurosciences, Institute of Anatomy and Cell Biology, Philipps-University, Marburg, Germany
| | - Burkhard Schütz
- Department of Molecular Neurosciences, Institute of Anatomy and Cell Biology, Philipps-University, Marburg, Germany
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41
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Sreenivasan V, Menon SN, Sinha S. Emergence of coupling-induced oscillations and broken symmetries in heterogeneously driven nonlinear reaction networks. Sci Rep 2017; 7:1594. [PMID: 28487568 PMCID: PMC5431650 DOI: 10.1038/s41598-017-01670-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 04/03/2017] [Indexed: 01/02/2023] Open
Abstract
Many natural systems including the brain comprise coupled elements that are stimulated non-uniformly. In this paper we show that heterogeneously driven networks of excitatory-inhibitory units exhibit a diverse range of collective phenomena, including the appearance of spontaneous oscillations upon coupling quiescent elements. On varying the coupling strength a previously unreported transition is seen wherein the symmetries of the synchronization patterns in the stimulated and unstimulated groups undergo mutual exchange. The system also exhibits coexisting chaotic and non-chaotic attractors - a result that may be of interest in connection to earlier reports of varying degrees of chaoticity in the brain.
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Affiliation(s)
- Varsha Sreenivasan
- The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai, 600113, India
| | - Shakti N Menon
- The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai, 600113, India
| | - Sitabhra Sinha
- The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai, 600113, India.
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42
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Pignatelli A, Belluzzi O. Dopaminergic Neurones in the Main Olfactory Bulb: An Overview from an Electrophysiological Perspective. Front Neuroanat 2017; 11:7. [PMID: 28261065 PMCID: PMC5306133 DOI: 10.3389/fnana.2017.00007] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 02/02/2017] [Indexed: 02/03/2023] Open
Abstract
The olfactory bulb (OB), the first center processing olfactory information, is characterized by a vigorous life-long activity-dependent plasticity responsible for a variety of odor-evoked behavioral responses. It hosts the more numerous group of dopaminergic (DA) neurones in the central nervous system, cells strategically positioned at the entry of the bulbar circuitry, directly in contact with the olfactory nerve terminals, which play a key role in odor processing and in the adaptation of the bulbar network to external conditions. Here, we focus mainly on the electrophysiological properties of DA interneurones, reviewing findings concerning their excitability profiles in adulthood and in different phases of adult neurogenesis. We also discuss dynamic changes of the DA interneurones related to environmental stimuli and their possible functional implications.
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Affiliation(s)
- Angela Pignatelli
- Life Sciences and Biotechnology, University of Ferrara Ferrara, Italy
| | - Ottorino Belluzzi
- Life Sciences and Biotechnology, University of Ferrara Ferrara, Italy
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43
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Mesquita L, Bruhn F, Maiorka P, Howerth E. Expression Kinetics of RANTES and MCP-1 in the Brain of Deer Mice ( Peromyscus maniculatus ) Infected with Vesicular Stomatitis New Jersey Virus. J Comp Pathol 2016; 155:326-338. [DOI: 10.1016/j.jcpa.2016.09.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 09/08/2016] [Accepted: 09/17/2016] [Indexed: 02/03/2023]
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44
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Distorted Coarse Axon Targeting and Reduced Dendrite Connectivity Underlie Dysosmia after Olfactory Axon Injury. eNeuro 2016; 3:eN-NWR-0242-16. [PMID: 27785463 PMCID: PMC5066264 DOI: 10.1523/eneuro.0242-16.2016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 09/21/2016] [Accepted: 09/24/2016] [Indexed: 11/21/2022] Open
Abstract
The glomerular map in the olfactory bulb (OB) is the basis for odor recognition. Once established during development, the glomerular map is stably maintained throughout the life of an animal despite the continuous turnover of olfactory sensory neurons (OSNs). However, traumatic damage to OSN axons in the adult often leads to dysosmia, a qualitative and quantitative change in olfaction in humans. A mouse model of dysosmia has previously indicated that there is an altered glomerular map in the OB after the OSN axon injury; however, the underlying mechanisms that cause the map distortion remain unknown. In this study, we examined how the glomerular map is disturbed and how the odor information processing in the OB is affected in the dysosmia model mice. We found that the anterior–posterior coarse targeting of OSN axons is disrupted after OSN axon injury, while the local axon sorting mechanisms remained. We also found that the connectivity of mitral/tufted cell dendrites is reduced after injury, leading to attenuated odor responses in mitral/tufted cells. These results suggest that existing OSN axons are an essential scaffold for maintaining the integrity of the olfactory circuit, both OSN axons and mitral/tufted cell dendrites, in the adult.
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45
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Bourne JN, Schoppa NE. Three-dimensional synaptic analyses of mitral cell and external tufted cell dendrites in rat olfactory bulb glomeruli. J Comp Neurol 2016; 525:592-609. [PMID: 27490056 DOI: 10.1002/cne.24089] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 06/13/2016] [Accepted: 07/28/2016] [Indexed: 11/07/2022]
Abstract
Recent studies have suggested that the two excitatory cell classes of the mammalian olfactory bulb, the mitral cells (MCs) and tufted cells (TCs), differ markedly in physiological responses. For example, TCs are more sensitive and broadly tuned to odors than MCs and also are much more sensitive to stimulation of olfactory sensory neurons (OSNs) in bulb slices. To examine the morphological bases for these differences, we performed quantitative ultrastructural analyses of glomeruli in rat olfactory bulb under conditions in which specific cells were labeled with biocytin and 3,3'-diaminobenzidine. Comparisons were made between MCs and external TCs (eTCs), which are a TC subtype in the glomerular layer with large, direct OSN signals and capable of mediating feedforward excitation of MCs. Three-dimensional analysis of labeled apical dendrites under an electron microscope revealed that MCs and eTCs in fact have similar densities of several chemical synapse types, including OSN inputs. OSN synapses also were distributed similarly, favoring a distal localization on both cells. Analysis of unlabeled putative MC dendrites further revealed gap junctions distributed uniformly along the apical dendrite and, on average, proximally with respect to OSN synapses. Our results suggest that the greater sensitivity of eTCs vs. MCs is due not to OSN synapse number or absolute location but rather to a conductance in the MC dendrite that is well positioned to attenuate excitatory signals passing to the cell soma. Functionally, such a mechanism could allow rapid and dynamic control of OSN-driven action potential firing in MCs through changes in gap junction properties. J. Comp. Neurol. 525:592-609, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Jennifer N Bourne
- Department of Physiology and Biophysics, University of Colorado School of Medicine, Aurora, Colorado, 80045
| | - Nathan E Schoppa
- Department of Physiology and Biophysics, University of Colorado School of Medicine, Aurora, Colorado, 80045.,Neuroscience Program, University of Colorado School of Medicine, Aurora, Colorado, 80045
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46
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The average baboon brain: MRI templates and tissue probability maps from 89 individuals. Neuroimage 2016; 132:526-533. [DOI: 10.1016/j.neuroimage.2016.03.018] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 02/17/2016] [Accepted: 03/07/2016] [Indexed: 01/08/2023] Open
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47
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Yoshihara SI, Takahashi H, Tsuboi A. Molecular Mechanisms Regulating the Dendritic Development of Newborn Olfactory Bulb Interneurons in a Sensory Experience-Dependent Manner. Front Neurosci 2016; 9:514. [PMID: 26793053 PMCID: PMC4709855 DOI: 10.3389/fnins.2015.00514] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 12/22/2015] [Indexed: 12/02/2022] Open
Abstract
Inhibitory interneurons in the olfactory bulb are generated continuously throughout life in the subventricular zone and differentiate into periglomerular and granule cells. Neural circuits that undergo reorganization by newborn olfactory bulb interneurons are necessary for odor detection, odor discrimination, olfactory memory, and innate olfactory responses. Although sensory experience has been shown to regulate development in a variety of species and in various structures, including the retina, cortex, and hippocampus, little is known about how sensory experience regulates the dendritic development of newborn olfactory bulb interneurons. Recent studies revealed that the 5T4 oncofetal trophoblast glycoprotein and the neuronal Per/Arnt/Sim domain protein 4 (Npas4) transcription factor regulate dendritic branching and dendritic spine formation, respectively, in olfactory bulb interneurons. Here, we summarize the molecular mechanisms that underlie the sensory input-dependent development of newborn interneurons and the formation of functional neural circuitry in the olfactory bulb.
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Affiliation(s)
- Sei-Ichi Yoshihara
- Laboratory for the Molecular Biology of Neural Systems, Advanced Medical Research Center, Nara Medical University Kashihara, Japan
| | - Hiroo Takahashi
- Laboratory for the Molecular Biology of Neural Systems, Advanced Medical Research Center, Nara Medical University Kashihara, Japan
| | - Akio Tsuboi
- Laboratory for the Molecular Biology of Neural Systems, Advanced Medical Research Center, Nara Medical University Kashihara, Japan
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48
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Affiliation(s)
- Anne Tromelin
- CNRS; UMR6265 Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
- INRA; UMR1324 Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
- Université de Bourgogne; UMR Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
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49
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Neuronal organization of the main olfactory bulb revisited. Anat Sci Int 2015; 91:115-27. [PMID: 26514846 DOI: 10.1007/s12565-015-0309-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 10/08/2015] [Indexed: 10/22/2022]
Abstract
The main olfactory bulb is now one of the most interesting parts of the brain; firstly as an excellent model for understanding the neural mechanisms of sensory information processing, and secondly as one of the most prominent sites whose interneurons are generated continuously in the postnatal and adult periods. The neuronal organization of the main olfactory bulb is fundamentally important as the basis of ongoing and future studies. In this review we focus on four issues, some of which appear not to have been recognized previously: (1) axons of periglomerular cells, (2) the heterogeneity and peculiarity of dopamine-GABAergic juxtaglomerular cells, (3) neurons participating in the interglomerular connections, and (4) newly found transglomerular cells.
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50
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Guimaraes IM, Carvalho TG, Ferguson SS, Pereira GS, Ribeiro FM. The metabotropic glutamate receptor 5 role on motor behavior involves specific neural substrates. Mol Brain 2015; 8:24. [PMID: 25885370 PMCID: PMC4397819 DOI: 10.1186/s13041-015-0113-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 03/24/2015] [Indexed: 11/22/2022] Open
Abstract
Background The metabotropic glutamate receptor 5 (mGluR5) is involved in various brain functions, including memory, cognition and motor behavior. Regarding locomotor activity, we and others have demonstrated that pharmacological antagonism of mGluR5 promotes hyperkinesia in mice. Moreover, increased locomotor activity can also be observed in mice following the genetic deletion of mGluR5. However, it is still unclear which specific brain substrates contribute to mGluR5-mediated regulation of motor function. Results Thus, to better understand the role of mGluR5 in motor control and to determine which neural substrates are involved in this regulation we performed stereotactic microinfusions of the mGluR5 antagonist, MPEP, into specific brain regions and submitted mice to the open field and rotarod apparatus. Our findings indicate that mGluR5 blockage elicits distinct outcomes in terms of locomotor activity and motor coordination depending on the brain region injected with mGluR5 antagonist. MPEP injection into either the dorsal striatum or dorsal hippocampus resulted in increased locomotor activity, whereas MPEP injection into either the ventral striatum or motor cortex resulted in hypokinesia. Moreover, MPEP injected into the olfactory bulb increased the distance mice traveled in the center of the open field arena. With respect to motor coordination on the rotarod, injection of MPEP into the motor cortex and olfactory bulb elicited decreased latency to fall. Conclusions Taken together, our data suggest that not only primarily motor neural substrates, but also limbic and sensory structures are involved in mGluR5-mediated motor behavior. Electronic supplementary material The online version of this article (doi:10.1186/s13041-015-0113-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Isabella M Guimaraes
- Departamento de Bioquimica e Imunologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil.
| | - Toniana G Carvalho
- Departamento de Bioquimica e Imunologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil.
| | - Stephen Sg Ferguson
- J. Allyn Taylor Centre for Cell Biology, Robarts Research Institute, University of Western Ontario, London, Ontario, N6A 5 K8, Canada.
| | - Grace S Pereira
- Nucleo de Neurociencias, Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil.
| | - Fabiola M Ribeiro
- Departamento de Bioquimica e Imunologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil.
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