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Dong J, Zhu XN, Zeng PM, Cao DD, Yang Y, Hu J, Luo ZG. A hominoid-specific signaling axis regulating the tempo of synaptic maturation. Cell Rep 2024; 43:114548. [PMID: 39052482 DOI: 10.1016/j.celrep.2024.114548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 04/15/2024] [Accepted: 07/12/2024] [Indexed: 07/27/2024] Open
Abstract
Human cortical neurons (hCNs) exhibit high dendritic complexity and synaptic density, and the maturation process is greatly protracted. However, the molecular mechanism governing these specific features remains unclear. Here, we report that the hominoid-specific gene TBC1D3 promotes dendritic arborization and protracts the pace of synaptogenesis. Ablation of TBC1D3 in induced hCNs causes reduction of dendritic growth and precocious synaptic maturation. Forced expression of TBC1D3 in the mouse cortex protracts synaptic maturation while increasing dendritic growth. Mechanistically, TBC1D3 functions via interaction with MICAL1, a monooxygenase that mediates oxidation of actin filament. At the early stage of differentiation, the TBC1D3/MICAL1 interaction in the cytosol promotes dendritic growth via F-actin oxidation and enhanced actin dynamics. At late stages, TBC1D3 escorts MICAL1 into the nucleus and downregulates the expression of genes related with synaptic maturation through interaction with the chromatin remodeling factor ATRX. Thus, this study delineates the molecular mechanisms underlying human neuron development.
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Affiliation(s)
- Jian Dong
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China; State Key Laboratory of Advanced Medical Materials and Devices, ShanghaiTech University, Shanghai 201210, China
| | - Xiao-Na Zhu
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Peng-Ming Zeng
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China; State Key Laboratory of Advanced Medical Materials and Devices, ShanghaiTech University, Shanghai 201210, China
| | - Dong-Dong Cao
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China; State Key Laboratory of Advanced Medical Materials and Devices, ShanghaiTech University, Shanghai 201210, China
| | - Yang Yang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China; State Key Laboratory of Advanced Medical Materials and Devices, ShanghaiTech University, Shanghai 201210, China
| | - Ji Hu
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Zhen-Ge Luo
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China; State Key Laboratory of Advanced Medical Materials and Devices, ShanghaiTech University, Shanghai 201210, China.
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2
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Deng XH, Liu XY, Wei YH, Wang K, Zhu JR, Zhong JJ, Zheng JY, Guo R, Zhu YF, Ye QH, Wang MD, Chen YJ, He JQ, Chen ZX, Huang SQ, Lv CS, Zheng GQ, Liu SF, Wen L. ErbB4 deficiency exacerbates olfactory dysfunction in an early-stage Alzheimer's disease mouse model. Acta Pharmacol Sin 2024:10.1038/s41401-024-01332-6. [PMID: 38982150 DOI: 10.1038/s41401-024-01332-6] [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: 02/13/2024] [Accepted: 06/02/2024] [Indexed: 07/11/2024] Open
Abstract
Olfactory dysfunction is increasingly recognized as an early indicator of Alzheimer's disease (AD). Aberrations in GABAergic function and the excitatory/inhibitory (E/I) balance within the olfactory bulb (OB) have been implicated in olfactory impairment during the initial stages of AD. While the neuregulin 1 (NRG1)/ErbB4 signaling pathway is known to regulate GABAergic transmission in the brain and is associated with various neuropsychiatric disorders, its specific role in early AD-related olfactory impairment remains incompletely understood. This study demonstrated that olfactory dysfunction preceded cognitive decline in young adult APP/PS1 mice and was characterized by reduced levels of NRG1 and ErbB4 in the OB. Further investigation revealed that deletion of ErbB4 in parvalbumin interneurons reduced GABAergic transmission and increased hyperexcitability in mitral and tufted cells (M/Ts) in the OB, thereby accelerating olfactory dysfunction in young adult APP/PS1 mice. Additionally, ErbB4 deficiency was associated with increased accumulation of Aβ and BACE1-mediated cleavage of APP, along with enhanced CDK5 signaling in the OB. NRG1 infusion into the OB was found to enhance GABAergic transmission in M/Ts and alleviate olfactory dysfunction in young adult APP/PS1 mice. These findings underscore the critical role of NRG1/ErbB4 signaling in regulating GABAergic transmission and E/I balance within the OB, contributing to olfactory impairment in young adult APP/PS1 mice, and provide novel insights for early intervention strategies in AD. This work has shown that ErbB4 deficiency increased the burden of Aβ, impaired GABAergic transmission, and disrupted the E/I balance of mitral and tufted cells (M/Ts) in the OB, ultimately resulting in olfactory dysfunction in young adult APP/PS1 mice. NRG1 could enhance GABAergic transmission, rescue E/I imbalance in M/Ts, and alleviate olfactory dysfunction in young adult APP/PS1 mice. OB: olfactory bulb, E/I: excitation/inhibition, Pr: probability of release, PV: parvalbumin interneurons, Aβ: β-amyloid, GABA: gamma-aminobutyric acid.
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Affiliation(s)
- Xian-Hua Deng
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
- Department of Neurology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China
| | - Xing-Yang Liu
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
- Department of Neurology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China
| | - Yi-Hua Wei
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
- Department of Neurology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China
| | - Ke Wang
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
- Department of Neurology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China
| | - Jun-Rong Zhu
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Jia-Jun Zhong
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Jing-Yuan Zheng
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Rui Guo
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Yi-Fan Zhu
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Qiu-Hong Ye
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Meng-Dan Wang
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Ying-Jie Chen
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Jian-Quan He
- Zhongshan Hospital, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Ze-Xu Chen
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Shu-Qiong Huang
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Chong-Shan Lv
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China
| | - Guo-Qing Zheng
- Department of Neurology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, 310006, China.
| | - Sui-Feng Liu
- Zhongshan Hospital, School of Medicine, Xiamen University, Xiamen, 361000, China.
| | - Lei Wen
- Center for Brain Sciences, The First Affiliated Hospital of Xiamen University, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361000, China.
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3
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Sakelaris B, Riecke H. Adult Neurogenesis Reconciles Flexibility and Stability of Olfactory Perceptual Memory. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.03.583153. [PMID: 38737721 PMCID: PMC11087939 DOI: 10.1101/2024.03.03.583153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/14/2024]
Abstract
In brain regions featuring ongoing plasticity, the task of quickly encoding new information without overwriting old memories presents a significant challenge. In the rodent olfactory bulb, which is renowned for substantial structural plasticity driven by adult neurogenesis and persistent turnover of dendritic spines, we show that such plasticity is vital to overcoming this flexibility-stability dilemma. To do so, we develop a computational model for structural plasticity in the olfactory bulb and show that the maturation of adult-born neurons facilitates the abilities to learn quickly and forget slowly. Particularly important to achieve this goal are the transient enhancement of the plasticity, excitability, and susceptibility to apoptosis that characterizes young neurons. The model captures many experimental observations and makes a number of testable predictions. Overall, it identifies memory consolidation as an important role of adult neurogenesis in olfaction and exemplifies how the brain can maintain stable memories despite ongoing extensive plasticity.
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Affiliation(s)
- Bennet Sakelaris
- Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, Illinois, United States of America
| | - Hermann Riecke
- Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, Illinois, United States of America
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4
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Ferreira A, Constantinescu VS, Malvaut S, Saghatelyan A, Hardy SV. Distinct forms of structural plasticity of adult-born interneuron spines in the mouse olfactory bulb induced by different odor learning paradigms. Commun Biol 2024; 7:420. [PMID: 38582915 PMCID: PMC10998910 DOI: 10.1038/s42003-024-06115-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 03/27/2024] [Indexed: 04/08/2024] Open
Abstract
The morpho-functional properties of neural networks constantly adapt in response to environmental stimuli. The olfactory bulb is particularly prone to constant reshaping of neural networks because of ongoing neurogenesis. It remains unclear whether the complexity of distinct odor-induced learning paradigms and sensory stimulation induces different forms of structural plasticity. In the present study, we automatically reconstructed spines in 3D from confocal images and performed unsupervised clustering based on morphometric features. We show that while sensory deprivation decreased the spine density of adult-born neurons without affecting the morphometric properties of these spines, simple and complex odor learning paradigms triggered distinct forms of structural plasticity. A simple odor learning task affected the morphometric properties of the spines, whereas a complex odor learning task induced changes in spine density. Our work reveals distinct forms of structural plasticity in the olfactory bulb tailored to the complexity of odor-learning paradigms and sensory inputs.
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Affiliation(s)
- Aymeric Ferreira
- CERVO Brain Research Center, Quebec City, QC, G1J 2G3, Canada
- Department of Biochemistry, Microbiology, and Bioinformatics, Université Laval, Quebec City, QC, G1V 0A6, Canada
| | - Vlad-Stefan Constantinescu
- CERVO Brain Research Center, Quebec City, QC, G1J 2G3, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Quebec City, QC, G1V 0A6, Canada
| | - Sarah Malvaut
- CERVO Brain Research Center, Quebec City, QC, G1J 2G3, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Quebec City, QC, G1V 0A6, Canada
| | - Armen Saghatelyan
- CERVO Brain Research Center, Quebec City, QC, G1J 2G3, Canada.
- Department of Psychiatry and Neuroscience, Université Laval, Quebec City, QC, G1V 0A6, Canada.
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1N 6N5, Canada.
| | - Simon V Hardy
- CERVO Brain Research Center, Quebec City, QC, G1J 2G3, Canada.
- Department of Biochemistry, Microbiology, and Bioinformatics, Université Laval, Quebec City, QC, G1V 0A6, Canada.
- Department of Computer Science and Software Engineering, Université Laval, Quebec City, QC, G1V 0A6, Canada.
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5
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Bao S, Romero JM, Belfort BD, Arenkiel BR. Signaling mechanisms underlying activity-dependent integration of adult-born neurons in the mouse olfactory bulb. Genesis 2024; 62:e23595. [PMID: 38553878 PMCID: PMC10987073 DOI: 10.1002/dvg.23595] [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: 01/10/2024] [Revised: 03/18/2024] [Accepted: 03/19/2024] [Indexed: 04/02/2024]
Abstract
Adult neurogenesis has fascinated the field of neuroscience for decades given the prospects of harnessing mechanisms that facilitate the rewiring and/or replacement of adult brain tissue. The subgranular zone of the hippocampus and the subventricular zone of the lateral ventricle are the two main areas in the brain that exhibit ongoing neurogenesis. Of these, adult-born neurons within the olfactory bulb have proven to be a powerful model for studying circuit plasticity, providing a broad and accessible avenue into neuron development, migration, and continued circuit integration within adult brain tissue. This review focuses on some of the recognized molecular and signaling mechanisms underlying activity-dependent adult-born neuron development. Notably, olfactory activity and behavioral states contribute to adult-born neuron plasticity through sensory and centrifugal inputs, in which calcium-dependent transcriptional programs, local translation, and neuropeptide signaling play important roles. This review also highlights areas of needed continued investigation to better understand the remarkable phenomenon of adult-born neuron integration.
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Affiliation(s)
- Suyang Bao
- Development, Disease Models, and Therapeutics Graduate Program, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas 77030, USA
| | - Juan M. Romero
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas 77030, USA
- Medical Scientist Training Program, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Benjamin D.W. Belfort
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas 77030, USA
- Medical Scientist Training Program, Baylor College of Medicine, Houston, Texas 77030, USA
- Genetics and Genomics Graduate Program, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Benjamin R. Arenkiel
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas 77030, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030, USA
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6
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de Castro CM, Almeida-Santos AF, Mansk LMZ, Jaimes LF, Cammarota M, Pereira GS. BDNF-dependent signaling in the olfactory bulb modulates social recognition memory in mice. Neurobiol Learn Mem 2024; 208:107891. [PMID: 38237799 DOI: 10.1016/j.nlm.2024.107891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 01/08/2024] [Accepted: 01/14/2024] [Indexed: 01/28/2024]
Abstract
An operative olfactory bulb (OB) is critical to social recognition memory (SRM) in rodents, which involves identifying conspecifics. Furthermore, OB also allocates synaptic plasticity events related to olfactory memories in their intricate neural circuit. Here, we asked whether the OB is a target for brain-derived neurotrophic factor (BDNF), a well-known mediator of plasticity and memory. Adult ICR-CD1 male mice had their SRM evaluated under the inhibition of BDNF-dependent signaling directly in the OB. We also quantified the expression of BDNF in the OB, after SRM acquisition. Our results presented an amnesic effect of anti-BDNF administered 12 h post-training. Although the western blot showed no statistical difference in pro-BDNF and BDNF expression, the analysis of fluorescence intensity in slices suggests SRM acquisition decreases BDNF in the granular cell layer of the OB. Next, to test the ability of BDNF to rescue SRM deficit, we administered the human recombinant BDNF (rBDNF) directly in the OB of socially isolated (SI) mice. Unexpectedly, rBDNF did not rescue SRM in SI mice. Furthermore, BDNF and pro-BDNF expression in the OB was unchanged by SI. Our study reinforces the OB as a plasticity locus in memory-related events. It also adds SRM as another type of memory sensitive to BDNF-dependent signaling.
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Affiliation(s)
- Caio M de Castro
- Núcleo de Neurociências, Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Brazil
| | - Ana F Almeida-Santos
- Departamento de Pesquisa e Desenvolvimento, Fundação Cristiano Varela. Faculdade de Minas- Faminas, Brazil
| | - Lara M Z Mansk
- Núcleo de Neurociências, Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Brazil
| | - Laura F Jaimes
- Núcleo de Neurociências, Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Brazil
| | - Martín Cammarota
- Memory Research Laboratory, Brain Institute, Federal University of Rio Grande do, Norte, Brazil
| | - Grace S Pereira
- Núcleo de Neurociências, Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Brazil.
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7
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Whiddon ZD, Marshall JB, Alston DC, McGee AW, Krimm RF. Rapid structural remodeling of peripheral taste neurons is independent of taste cell turnover. PLoS Biol 2023; 21:e3002271. [PMID: 37651406 PMCID: PMC10499261 DOI: 10.1371/journal.pbio.3002271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 09/13/2023] [Accepted: 07/22/2023] [Indexed: 09/02/2023] Open
Abstract
Taste bud cells are constantly replaced in taste buds as old cells die and new cells migrate into the bud. The perception of taste relies on new taste bud cells integrating with existing neural circuitry, yet how these new cells connect with a taste ganglion neuron is unknown. Do taste ganglion neurons remodel to accommodate taste bud cell renewal? If so, how much of the structure of taste axons is fixed and how much remodels? Here, we measured the motility and branching of individual taste arbors (the portion of the axon innervating taste buds) in mice over time with two-photon in vivo microscopy. Terminal branches of taste arbors continuously and rapidly remodel within the taste bud. This remodeling is faster than predicted by taste bud cell renewal, with terminal branches added and lost concurrently. Surprisingly, blocking entry of new taste bud cells with chemotherapeutic agents revealed that remodeling of the terminal branches on taste arbors does not rely on the renewal of taste bud cells. Although terminal branch remodeling was fast and intrinsically controlled, no new arbors were added to taste buds, and few were lost over 100 days. Taste ganglion neurons maintain a stable number of arbors that are each capable of high-speed remodeling. We propose that terminal branch plasticity permits arbors to locate new taste bud cells, while stability of arbor number supports constancy in the degree of connectivity and function for each neuron over time.
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Affiliation(s)
- Zachary D. Whiddon
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky, United States of America
| | - Jaleia B. Marshall
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky, United States of America
| | - David C. Alston
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky, United States of America
| | - Aaron W. McGee
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky, United States of America
| | - Robin F. Krimm
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky, United States of America
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8
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Ogawa B, Nakanishi Y, Wakamatsu M, Takahashi Y, Shibutani M. Repeated administration of acrylamide for 28 days suppresses adult neurogenesis of the olfactory bulb in young-adult rats. Toxicol Lett 2023; 378:1-9. [PMID: 36801352 DOI: 10.1016/j.toxlet.2023.02.004] [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: 10/23/2022] [Revised: 01/22/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023]
Abstract
Acrylamide (AA) is a neurotoxicant that inhibits synaptic function in distal axons. We previously found that AA decreased neural cell lineages during late-stage differentiation of adult hippocampal neurogenesis and downregulated genes related to neurotrophic factor, neuronal migration, neurite outgrowth, and synapse formation in the hippocampal dentate gyrus in rats. To investigate whether olfactory bulb (OB)-subventricular zone (SVZ) neurogenesis is similarly affected by AA exposure, AA was administered to 7-week-old male rats via oral gavage at doses of 0, 5, 10, and 20 mg/kg for 28 days. Immunohistochemical analysis revealed that AA decreased the numbers of doublecortin-positive (+) cells and polysialic acid-neural cell adhesion molecule+ cells in the OB. On the other hand, the numbers of doublecortin+ cells and polysialic acid-neural cell adhesion molecule+ cells in the SVZ did not change with AA exposure, suggesting that AA impaired neuroblasts migrating in the rostral migratory stream and OB. Gene expression analysis in the OB revealed that AA downregulated Bdnf and Ncam2, which are related to neuronal differentiation and migration. These results suggest that AA decreased neuroblasts in the OB by suppressing neuronal migration. Thus, AA decreased neuronal cell lineages during late-stage differentiation of adult neurogenesis in the OB-SVZ, similar to the effect on adult hippocampal neurogenesis.
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Affiliation(s)
- Bunichiro Ogawa
- Drug Safety and Pharmacokinetics Laboratories, Taisho Pharmaceutical Co., Ltd., 1-403 Yoshino-cho, Kita-ku, Saitama-shi, Saitama 331-9530, Japan; Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan.
| | - Yutaka Nakanishi
- Drug Safety and Pharmacokinetics Laboratories, Taisho Pharmaceutical Co., Ltd., 1-403 Yoshino-cho, Kita-ku, Saitama-shi, Saitama 331-9530, Japan.
| | - Masaki Wakamatsu
- Drug Safety and Pharmacokinetics Laboratories, Taisho Pharmaceutical Co., Ltd., 1-403 Yoshino-cho, Kita-ku, Saitama-shi, Saitama 331-9530, Japan.
| | - Yasunori Takahashi
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan.
| | - Makoto Shibutani
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan; Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan.
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9
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Meng JH, Riecke H. Structural spine plasticity: Learning and forgetting of odor-specific subnetworks in the olfactory bulb. PLoS Comput Biol 2022; 18:e1010338. [PMID: 36279303 PMCID: PMC9632792 DOI: 10.1371/journal.pcbi.1010338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 11/03/2022] [Accepted: 09/28/2022] [Indexed: 11/05/2022] Open
Abstract
Learning to discriminate between different sensory stimuli is essential for survival. In rodents, the olfactory bulb, which contributes to odor discrimination via pattern separation, exhibits extensive structural synaptic plasticity involving the formation and removal of synaptic spines, even in adult animals. The network connectivity resulting from this plasticity is still poorly understood. To gain insight into this connectivity we present here a computational model for the structural plasticity of the reciprocal synapses between the dominant population of excitatory principal neurons and inhibitory interneurons. It incorporates the observed modulation of spine stability by odor exposure. The model captures the striking experimental observation that the exposure to odors does not always enhance their discriminability: while training with similar odors enhanced their discriminability, training with dissimilar odors actually reduced the discriminability of the training stimuli. Strikingly, this differential learning does not require the activity-dependence of the spine stability and occurs also in a model with purely random spine dynamics in which the spine density is changed homogeneously, e.g., due to a global signal. However, the experimentally observed odor-specific reduction in the response of principal cells as a result of extended odor exposure and the concurrent disinhibition of a subset of principal cells arise only in the activity-dependent model. Moreover, this model predicts the experimentally testable recovery of odor response through weak but not through strong odor re-exposure and the forgetting of odors via exposure to interfering odors. Combined with the experimental observations, the computational model provides strong support for the prediction that odor exposure leads to the formation of odor-specific subnetworks in the olfactory bulb. A key feature of the brain is its ability to learn through the plasticity of its network. The olfactory bulb in the olfactory system is a remarkable brain area whose anatomical structure evolves substantially still in adult animals by establishing new synaptic connections and removing existing ones. We present a computational model for this process and employ it to interpret recent experimental results. By comparing the results of our model with those of a random control model we identify various experimental observations that lend strong support to the notion that the network of the olfactory bulb comprises learned, odor-specific subnetworks. Moreover, our model explains the recent observation that the learning of odors does not always improve their discriminability and provides testable predictions for the recovery of odor response after repeated odor exposure and for when the learning of new odors interferes with retaining the memory of familiar odors.
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Affiliation(s)
- John Hongyu Meng
- Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, Illinois, United States of America
| | - Hermann Riecke
- Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, Illinois, United States of America
- * E-mail:
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10
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Kurematsu C, Sawada M, Ohmuraya M, Tanaka M, Kuboyama K, Ogino T, Matsumoto M, Oishi H, Inada H, Ishido Y, Sakakibara Y, Nguyen HB, Thai TQ, Kohsaka S, Ohno N, Yamada MK, Asai M, Sokabe M, Nabekura J, Asano K, Tanaka M, Sawamoto K. Synaptic pruning of murine adult-born neurons by microglia depends on phosphatidylserine. J Exp Med 2022; 219:213073. [PMID: 35297954 PMCID: PMC9195048 DOI: 10.1084/jem.20202304] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 08/13/2021] [Accepted: 11/30/2021] [Indexed: 12/21/2022] Open
Abstract
New neurons, continuously added in the adult olfactory bulb (OB) and hippocampus, are involved in information processing in neural circuits. Here, we show that synaptic pruning of adult-born neurons by microglia depends on phosphatidylserine (PS), whose exposure on dendritic spines is inversely correlated with their input activity. To study the role of PS in spine pruning by microglia in vivo, we developed an inducible transgenic mouse line, in which the exposed PS is masked by a dominant-negative form of milk fat globule-EGF-factor 8 (MFG-E8), MFG-E8D89E. In this transgenic mouse, the spine pruning of adult-born neurons by microglia is impaired in the OB and hippocampus. Furthermore, the electrophysiological properties of these adult-born neurons are altered in MFG-E8D89E mice. These data suggest that PS is involved in the microglial spine pruning and the functional maturation of adult-born neurons. The MFG-E8D89E-based genetic approach shown in this study has broad applications for understanding the biology of PS-mediated phagocytosis in vivo.
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Affiliation(s)
- Chihiro Kurematsu
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Masato Sawada
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Division of Neural Development and Regeneration, National Institute for Physiological Sciences, Okazaki, Japan
| | - Masaki Ohmuraya
- Department of Genetics, Hyogo College of Medicine, Nishinomiya, Japan
| | - Motoki Tanaka
- Department of Disease Model, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Japan
| | - Kazuya Kuboyama
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Takashi Ogino
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Mami Matsumoto
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Section of Electron Microscopy, Supportive Center for Brain Research, National Institute for Physiological Sciences, Okazaki, Japan
| | - Hisashi Oishi
- Department of Comparative and Experimental Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Hiroyuki Inada
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki, Japan
| | - Yuri Ishido
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Yukina Sakakibara
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Huy Bang Nguyen
- Section of Electron Microscopy, Supportive Center for Brain Research, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Anatomy, Faculty of Medicine, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Truc Quynh Thai
- Section of Electron Microscopy, Supportive Center for Brain Research, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Histology-Embryology-Genetics, Faculty of Basic Medical Sciences, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Vietnam
| | - Shinichi Kohsaka
- National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Japan
| | - Nobuhiko Ohno
- Department of Anatomy, Division of Histology and Cell Biology, Jichi Medical University, School of Medicine, Shimotsuke, Japan.,Division of Ultrastructural Research, National Institute for Physiological Sciences, Okazaki, Japan
| | - Maki K Yamada
- Department of Neuropharmacology, Kagawa School of Pharmaceutical Sciences and Institute of Neuroscience, Tokushima Bunri University, Sanuki, Japan
| | - Masato Asai
- Department of Disease Model, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Japan
| | - Masahiro Sokabe
- Mechanobiology Laboratory, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Junichi Nabekura
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki, Japan
| | - Kenichi Asano
- Laboratory of Immune Regulation, Tokyo University of Pharmacy and Life Sciences, Hachioji, Japan
| | - Masato Tanaka
- Laboratory of Immune Regulation, Tokyo University of Pharmacy and Life Sciences, Hachioji, Japan
| | - Kazunobu Sawamoto
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Division of Neural Development and Regeneration, National Institute for Physiological Sciences, Okazaki, Japan
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11
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Marco-Manclus P, Ávila-González D, Paredes RG, Portillo W. Sexual experience in female mice involves synaptophysin-related plasticity in the accessory olfactory bulb. Physiol Behav 2022; 244:113649. [PMID: 34798129 DOI: 10.1016/j.physbeh.2021.113649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 11/12/2021] [Accepted: 11/13/2021] [Indexed: 10/19/2022]
Abstract
Sexually naïve female mice do not display high levels of sexual receptivity in their first sexual experience; they require around 4-5 sexual encounters to display the full receptive response, assessed by the lordosis reflex. In this study, we evaluated if repeated sexual stimulation with the same male is associated with changes in synaptic remodeling evaluated by synaptophysin (SYP) in brain structures involved in the control of sexual behavior such as the main and accessory olfactory bulbs (MOB and AOB, respectively), medial preoptic area (MPOA), ventromedial hypothalamus (VMH), and amygdala (AMG). Female mice were ovariectomized and hormonally primed to induce sexual receptivity. They were randomly distributed into three groups: a) sexually naïve (SN), with no prior sexual stimulation; b) sexually inexperienced (SI), with one prior mating session; and c) sexually experienced (SE), with six mating sessions. The SI group showed a significant decrease in SYP in the glomerular, mitral and granular layers of the AOB in comparison to SN and SE females. SYP expression increased in the SE group in comparison to SN and SI females in the glomerular and mitral cell layers of the AOB. No significant differences between groups were found in the other brain regions (MOB, MPOA, VMH or AMG). These changes in SYP expression in the AOB suggest that plastic modifications in this brain region can be associated with receptivity increase in sexual experience in female mice.
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Affiliation(s)
- P Marco-Manclus
- Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM). Juriquilla Querétaro, Mexico
| | - D Ávila-González
- Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM). Juriquilla Querétaro, Mexico
| | - R G Paredes
- Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM). Juriquilla Querétaro, Mexico; Escuela Nacional de Estudios Superiores, UNAM. Juriquilla Querétaro, Mexico
| | - W Portillo
- Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM). Juriquilla Querétaro, Mexico.
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12
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The Shape of the Olfactory Bulb Predicts Olfactory Function. Brain Sci 2022; 12:brainsci12020128. [PMID: 35203892 PMCID: PMC8870545 DOI: 10.3390/brainsci12020128] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 01/13/2022] [Accepted: 01/14/2022] [Indexed: 12/04/2022] Open
Abstract
The olfactory bulb (OB) plays a key role in the processing of olfactory information. A large body of research has shown that OB volumes correlate with olfactory function, which provides diagnostic and prognostic information in olfactory dysfunction. Still, the potential value of the OB shape remains unclear. Based on our clinical experience we hypothesized that the shape of the OB predicts olfactory function, and that it is linked to olfactory loss, age, and gender. The aim of this study was to produce a classification of OB shape in the human brain, scalable to clinical and research applications. Results from patients with the five most frequent causes of olfactory dysfunction (n = 192) as well as age/gender-matched healthy controls (n = 77) were included. Olfactory function was examined in great detail using the extended “Sniffin’ Sticks” test. A high-resolution structural T2-weighted MRI scan was obtained for all. The planimetric contours (surface in mm2) of OB were delineated manually, and then all surfaces were added and multiplied to obtain the OB volume in mm3. OB shapes were outlined manually and characterized on a selected slice through the posterior coronal plane tangential to the eyeballs. We looked at OB shapes in terms of convexity and defined two patterns/seven categories based on OB contours: convex (olive, circle, and plano-convex) and non-convex (banana, irregular, plane, and scattered). Categorization of OB shapes is possible with a substantial inter-rater agreement (Cohen’s Kappa = 0.73). Our results suggested that non-convex OB patterns were significantly more often observed in patients than in controls. OB shapes were correlated with olfactory function in the whole group, independent of age, gender, and OB volume. OB shapes seemed to change with age in healthy subjects. Importantly, the results indicated that OB shapes were associated with certain causes of olfactory disorders, i.e., an irregular OB shape was significantly more often observed in post-traumatic olfactory loss. Our study provides evidence that the shape of the OB can be used as a biomarker for olfactory dysfunction.
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13
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Forest J, Chalençon L, Midroit M, Terrier C, Caillé I, Sacquet J, Benetollo C, Martin K, Richard M, Didier A, Mandairon N. Role of Adult-Born Versus Preexisting Neurons Born at P0 in Olfactory Perception in a Complex Olfactory Environment in Mice. Cereb Cortex 2021; 30:534-549. [PMID: 31216001 DOI: 10.1093/cercor/bhz105] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 03/26/2019] [Accepted: 04/21/2019] [Indexed: 12/11/2022] Open
Abstract
Olfactory perceptual learning is defined as an improvement in the discrimination of perceptually close odorants after passive exposure to these odorants. In mice, simple olfactory perceptual learning involving the discrimination of two odorants depends on an increased number of adult-born neurons in the olfactory bulb, which refines the bulbar output. However, the olfactory environment is complex, raising the question of the adjustment of the bulbar network to multiple discrimination challenges. Perceptual learning of 1 to 6 pairs of similar odorants led to discrimination of all learned odor pairs. Increasing complexity did not increase adult-born neuron survival but enhanced the number of adult-born neurons responding to learned odorants and their spine density. Moreover, only complex learning induced morphological changes in neurons of the granule cell layer born during the first day of life (P0). Selective optogenetic inactivation of either population confirmed functional involvement of adult-born neurons regardless of the enrichment complexity, while preexisting neurons were required for complex discrimination only.
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Affiliation(s)
- Jérémy Forest
- INSERM, U1028; CNRS, UMR5292; Lyon Neuroscience Research Center, Neuroplasticity and Neuropathology of Olfactory Perception Team, Lyon, F-69000, France.,Claude Bernard University Lyon1 and University of Lyon, Lyon F-69000, France
| | - Laura Chalençon
- INSERM, U1028; CNRS, UMR5292; Lyon Neuroscience Research Center, Neuroplasticity and Neuropathology of Olfactory Perception Team, Lyon, F-69000, France.,Claude Bernard University Lyon1 and University of Lyon, Lyon F-69000, France
| | - Maëllie Midroit
- INSERM, U1028; CNRS, UMR5292; Lyon Neuroscience Research Center, Neuroplasticity and Neuropathology of Olfactory Perception Team, Lyon, F-69000, France.,Claude Bernard University Lyon1 and University of Lyon, Lyon F-69000, France
| | - Claire Terrier
- INSERM, U1028; CNRS, UMR5292; Lyon Neuroscience Research Center, Neuroplasticity and Neuropathology of Olfactory Perception Team, Lyon, F-69000, France.,Claude Bernard University Lyon1 and University of Lyon, Lyon F-69000, France
| | - Isabelle Caillé
- Sorbonne Universités, Université Pierre et Marie Curie-Paris 06, Centre National de la Recherche Scientifique, UMR8246, INSERM U1130, Institut de Biologie Paris Seine, Neuroscience Paris Seine, and Sorbonne Paris Cité, Université Paris Diderot-Paris 7, Paris, France
| | - Joëlle Sacquet
- INSERM, U1028; CNRS, UMR5292; Lyon Neuroscience Research Center, Neuroplasticity and Neuropathology of Olfactory Perception Team, Lyon, F-69000, France.,Claude Bernard University Lyon1 and University of Lyon, Lyon F-69000, France
| | - Claire Benetollo
- INSERM, U1028, CNRS, UMR5292, Lyon Neuroscience Research Center, Neurogenetic and Optogenetic Platform, University Lyon 1 and University of Lyon, Lyon F-69000, France
| | - Killian Martin
- INSERM, U1028; CNRS, UMR5292; Lyon Neuroscience Research Center, Neuroplasticity and Neuropathology of Olfactory Perception Team, Lyon, F-69000, France.,Claude Bernard University Lyon1 and University of Lyon, Lyon F-69000, France
| | - Marion Richard
- INSERM, U1028; CNRS, UMR5292; Lyon Neuroscience Research Center, Neuroplasticity and Neuropathology of Olfactory Perception Team, Lyon, F-69000, France.,Claude Bernard University Lyon1 and University of Lyon, Lyon F-69000, France
| | - Anne Didier
- INSERM, U1028; CNRS, UMR5292; Lyon Neuroscience Research Center, Neuroplasticity and Neuropathology of Olfactory Perception Team, Lyon, F-69000, France.,Claude Bernard University Lyon1 and University of Lyon, Lyon F-69000, France
| | - Nathalie Mandairon
- INSERM, U1028; CNRS, UMR5292; Lyon Neuroscience Research Center, Neuroplasticity and Neuropathology of Olfactory Perception Team, Lyon, F-69000, France.,Claude Bernard University Lyon1 and University of Lyon, Lyon F-69000, France
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14
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Gribaudo S, Saraulli D, Nato G, Bonzano S, Gambarotta G, Luzzati F, Costanzi M, Peretto P, Bovetti S, De Marchis S. Neurogranin Regulates Adult-Born Olfactory Granule Cell Spine Density and Odor-Reward Associative Memory in Mice. Int J Mol Sci 2021; 22:ijms22084269. [PMID: 33924098 PMCID: PMC8074334 DOI: 10.3390/ijms22084269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/14/2021] [Accepted: 04/16/2021] [Indexed: 11/16/2022] Open
Abstract
Neurogranin (Ng) is a brain-specific postsynaptic protein, whose role in modulating Ca2+/calmodulin signaling in glutamatergic neurons has been linked to enhancement in synaptic plasticity and cognitive functions. Accordingly, Ng knock-out (Ng-ko) mice display hippocampal-dependent learning and memory impairments associated with a deficit in long-term potentiation induction. In the adult olfactory bulb (OB), Ng is expressed by a large population of GABAergic granule cells (GCs) that are continuously generated during adult life, undergo high synaptic remodeling in response to the sensory context, and play a key role in odor processing. However, the possible implication of Ng in OB plasticity and function is yet to be investigated. Here, we show that Ng expression in the OB is associated with the mature state of adult-born GCs, where its active-phosphorylated form is concentrated at post-synaptic sites. Constitutive loss of Ng in Ng-ko mice resulted in defective spine density in adult-born GCs, while their survival remained unaltered. Moreover, Ng-ko mice show an impaired odor-reward associative memory coupled with reduced expression of the activity-dependent transcription factor Zif268 in olfactory GCs. Overall, our data support a role for Ng in the molecular mechanisms underlying GC plasticity and the formation of olfactory associative memory.
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Affiliation(s)
- Simona Gribaudo
- Department of Life Sciences and Systems Biology (DBIOS), University of Torino, 10123 Turin, Italy; (S.G.); (G.N.); (S.B.); (F.L.); (P.P.)
| | - Daniele Saraulli
- Institute of Cell Biology and Neurobiology (IBCN), National Research Council, 00143 Rome, Italy;
| | - Giulia Nato
- Department of Life Sciences and Systems Biology (DBIOS), University of Torino, 10123 Turin, Italy; (S.G.); (G.N.); (S.B.); (F.L.); (P.P.)
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, 10043 Turin, Italy;
| | - Sara Bonzano
- Department of Life Sciences and Systems Biology (DBIOS), University of Torino, 10123 Turin, Italy; (S.G.); (G.N.); (S.B.); (F.L.); (P.P.)
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, 10043 Turin, Italy;
| | - Giovanna Gambarotta
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, 10043 Turin, Italy;
- Department of Clinical and Biological Sciences (DSCB), University of Torino, 10043 Turin, Italy
| | - Federico Luzzati
- Department of Life Sciences and Systems Biology (DBIOS), University of Torino, 10123 Turin, Italy; (S.G.); (G.N.); (S.B.); (F.L.); (P.P.)
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, 10043 Turin, Italy;
| | - Marco Costanzi
- Department of Human Sciences, LUMSA University, 00193 Rome, Italy;
| | - Paolo Peretto
- Department of Life Sciences and Systems Biology (DBIOS), University of Torino, 10123 Turin, Italy; (S.G.); (G.N.); (S.B.); (F.L.); (P.P.)
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, 10043 Turin, Italy;
| | - Serena Bovetti
- Department of Life Sciences and Systems Biology (DBIOS), University of Torino, 10123 Turin, Italy; (S.G.); (G.N.); (S.B.); (F.L.); (P.P.)
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, 10043 Turin, Italy;
- Correspondence: (S.B.); (S.D.M.)
| | - Silvia De Marchis
- Department of Life Sciences and Systems Biology (DBIOS), University of Torino, 10123 Turin, Italy; (S.G.); (G.N.); (S.B.); (F.L.); (P.P.)
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, 10043 Turin, Italy;
- Correspondence: (S.B.); (S.D.M.)
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15
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Kermen F, Mandairon N, Chalençon L. Odor hedonics coding in the vertebrate olfactory bulb. Cell Tissue Res 2021; 383:485-493. [PMID: 33515292 PMCID: PMC7873110 DOI: 10.1007/s00441-020-03372-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 11/29/2020] [Indexed: 12/21/2022]
Abstract
Whether an odorant is perceived as pleasant or unpleasant (hedonic value) governs a range of crucial behaviors: foraging, escaping danger, and social interaction. Despite its importance in olfactory perception, little is known regarding how odor hedonics is represented and encoded in the brain. Here, we review recent findings describing how odorant hedonic value is represented in the first olfaction processing center, the olfactory bulb. We discuss how olfactory bulb circuits might contribute to the coding of innate and learned odorant hedonics in addition to the odorant's physicochemical properties.
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Affiliation(s)
- Florence Kermen
- Department of Biology, Faculty of Natural Sciences, Norwegian University of Science and Technology, 7030, Trondheim, Norway.
| | - Nathalie Mandairon
- CNRS. UMR 5292: INSERM, U1028: Lyon Neuroscience Research Center Neuroplasticity and Neuropathology of Olfactory Perception Team, University Lyon, University Lyon1, F-69000, Villeurbanne, France
| | - Laura Chalençon
- CNRS. UMR 5292: INSERM, U1028: Lyon Neuroscience Research Center Neuroplasticity and Neuropathology of Olfactory Perception Team, University Lyon, University Lyon1, F-69000, Villeurbanne, France
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16
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Navarro Negredo P, Yeo RW, Brunet A. Aging and Rejuvenation of Neural Stem Cells and Their Niches. Cell Stem Cell 2020; 27:202-223. [PMID: 32726579 DOI: 10.1016/j.stem.2020.07.002] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Aging has a profound and devastating effect on the brain. Old age is accompanied by declining cognitive function and enhanced risk of brain diseases, including cancer and neurodegenerative disorders. A key question is whether cells with regenerative potential contribute to brain health and even brain "rejuvenation." This review discusses mechanisms that regulate neural stem cells (NSCs) during aging, focusing on the effect of metabolism, genetic regulation, and the surrounding niche. We also explore emerging rejuvenating strategies for old NSCs. Finally, we consider how new technologies may help harness NSCs' potential to restore healthy brain function during physiological and pathological aging.
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Affiliation(s)
| | - Robin W Yeo
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Anne Brunet
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; Glenn Laboratories for the Biology of Aging, Stanford, CA 94305, USA.
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17
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Nguyen PT, Dorman LC, Pan S, Vainchtein ID, Han RT, Nakao-Inoue H, Taloma SE, Barron JJ, Molofsky AB, Kheirbek MA, Molofsky AV. Microglial Remodeling of the Extracellular Matrix Promotes Synapse Plasticity. Cell 2020; 182:388-403.e15. [PMID: 32615087 DOI: 10.1016/j.cell.2020.05.050] [Citation(s) in RCA: 297] [Impact Index Per Article: 74.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 04/20/2020] [Accepted: 05/27/2020] [Indexed: 12/21/2022]
Abstract
Synapse remodeling is essential to encode experiences into neuronal circuits. Here, we define a molecular interaction between neurons and microglia that drives experience-dependent synapse remodeling in the hippocampus. We find that the cytokine interleukin-33 (IL-33) is expressed by adult hippocampal neurons in an experience-dependent manner and defines a neuronal subset primed for synaptic plasticity. Loss of neuronal IL-33 or the microglial IL-33 receptor leads to impaired spine plasticity, reduced newborn neuron integration, and diminished precision of remote fear memories. Memory precision and neuronal IL-33 are decreased in aged mice, and IL-33 gain of function mitigates age-related decreases in spine plasticity. We find that neuronal IL-33 instructs microglial engulfment of the extracellular matrix (ECM) and that its loss leads to impaired ECM engulfment and a concomitant accumulation of ECM proteins in contact with synapses. These data define a cellular mechanism through which microglia regulate experience-dependent synapse remodeling and promote memory consolidation.
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Affiliation(s)
- Phi T Nguyen
- Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA, USA
| | - Leah C Dorman
- Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Neuroscience Graduate Program, University of California, San Francisco, San Francisco, CA, USA
| | - Simon Pan
- Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Neuroscience Graduate Program, University of California, San Francisco, San Francisco, CA, USA
| | - Ilia D Vainchtein
- Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Rafael T Han
- Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Hiromi Nakao-Inoue
- Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Sunrae E Taloma
- Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Jerika J Barron
- Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA, USA
| | - Ari B Molofsky
- Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Mazen A Kheirbek
- Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA, USA
| | - Anna V Molofsky
- Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA, USA.
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18
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Wu A, Yu B, Komiyama T. Plasticity in olfactory bulb circuits. Curr Opin Neurobiol 2020; 64:17-23. [PMID: 32062045 DOI: 10.1016/j.conb.2020.01.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 11/27/2019] [Accepted: 01/15/2020] [Indexed: 12/24/2022]
Abstract
Olfaction is crucial for animal survival and human well-being. The olfactory bulb is the obligatory input station for olfactory information. In contrast to the traditional view as a static relay station, recent evidence indicates that the olfactory bulb dynamically processes olfactory information in an experience-dependent and context-dependent manner. Here, we review recent studies on experience-dependent plasticity of the main circuit components within the olfactory bulb of rodents. We argue that the olfactory bulb plasticity allows optimal representations of behaviorally-relevant odors in the continuously changing olfactory environment.
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Affiliation(s)
- An Wu
- Neurobiology Section, Center for Neural Circuits and Behavior, University of California San Diego, La Jolla, CA 92093, USA; Department of Neurosciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Bin Yu
- Neurobiology Section, Center for Neural Circuits and Behavior, University of California San Diego, La Jolla, CA 92093, USA; Department of Neurosciences, University of California San Diego, La Jolla, CA 92093, USA; Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, CA 92093, USA
| | - Takaki Komiyama
- Neurobiology Section, Center for Neural Circuits and Behavior, University of California San Diego, La Jolla, CA 92093, USA; Department of Neurosciences, University of California San Diego, La Jolla, CA 92093, USA.
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19
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Bragado Alonso S, Reinert JK, Marichal N, Massalini S, Berninger B, Kuner T, Calegari F. An increase in neural stem cells and olfactory bulb adult neurogenesis improves discrimination of highly similar odorants. EMBO J 2019; 38:e98791. [PMID: 30643018 PMCID: PMC6418468 DOI: 10.15252/embj.201798791] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 11/14/2018] [Accepted: 11/15/2018] [Indexed: 01/17/2023] Open
Abstract
Adult neurogenesis is involved in cognitive performance but studies that manipulated this process to improve brain function are scarce. Here, we characterized a genetic mouse model in which neural stem cells (NSC) of the subventricular zone (SVZ) were temporarily expanded by conditional expression of the cell cycle regulators Cdk4/cyclinD1, thus increasing neurogenesis. We found that supernumerary neurons matured and integrated in the olfactory bulb similarly to physiologically generated newborn neurons displaying a correct expression of molecular markers, morphology and electrophysiological activity. Olfactory performance upon increased neurogenesis was unchanged when mice were tested on relatively easy tasks using distinct odor stimuli. In contrast, intriguingly, increasing neurogenesis improved the discrimination ability of mice when challenged with a difficult task using mixtures of highly similar odorants. Together, our study provides a mammalian model to control the expansion of somatic stem cells that can in principle be applied to any tissue for basic research and models of therapy. By applying this to NSC of the SVZ, we highlighted the importance of adult neurogenesis to specifically improve performance in a challenging olfactory task.
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Affiliation(s)
- Sara Bragado Alonso
- CRTD Center for Regenerative Therapies Dresden, School of Medicine, TU Dresden, Dresden, Germany
| | - Janine K Reinert
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Nicolas Marichal
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Centre for Developmental Neurobiology and MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Simone Massalini
- CRTD Center for Regenerative Therapies Dresden, School of Medicine, TU Dresden, Dresden, Germany
| | - Benedikt Berninger
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Centre for Developmental Neurobiology and MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Thomas Kuner
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Federico Calegari
- CRTD Center for Regenerative Therapies Dresden, School of Medicine, TU Dresden, Dresden, Germany
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20
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Maldonado-Ruiz R, Garza-Ocañas L, Camacho A. Inflammatory domains modulate autism spectrum disorder susceptibility during maternal nutritional programming. Neurochem Int 2019; 126:109-117. [PMID: 30880046 DOI: 10.1016/j.neuint.2019.03.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/30/2019] [Accepted: 03/11/2019] [Indexed: 12/21/2022]
Abstract
Autism spectrum disorder (ASD) is a complex neurodevelopmental disease which involves functional and structural defects in selective central nervous system (CNS) regions harming capability to process and respond to external stimuli. In addition to genetic background, etiological causes of ASD have not been fully clarified. Maternal immune activation (MIA) during pregnancy have been proposed as a potential etiological cause leading to aberrant synaptic pruning and microglia-mediated neurogenesis impairment. Several clinical studies suggest that pro-inflammatory profile during maternal obesity associates with a higher risk of having a child with autism. In this context, the effect of maternal programing by high fat diet overconsumption during pregnancy sets a pro-inflammatory profile partly dependent on an epigenetic program of immunity which promotes brain micro and macrostructural abnormalities in the offspring that might last through adulthood accompanied by phenotypic changes in ASD subjects. Of note, maternal programming of inflammation during development seems to integrate the CNS and peripheral immune system cross-talk which arrays central inflammatory domains coordinating ASD behavior. In this review, we discuss basic and clinical studies regarding the effects of obesity-induced MIA on peripheral immune cells and microglia priming and their relationship with brain structural alterations in ASD models. Also, we show supportive evidence stating the role of maternal programming on epigenetic gene activation in immune cells of ASD subjects. We suggest that maternal programming by hypercaloric diets during development sets a central and peripheral immune cross-talk which potentially might modulate brain macro and microstructural defects leading to autism susceptibility.
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Affiliation(s)
- Roger Maldonado-Ruiz
- Universidad Autónoma de Nuevo Leon, Facultad de Medicina, Biochemistry Department, Mexico; Universidad Autónoma de Nuevo Leon, Centro de Investigación y Desarrollo en Ciencias de la Salud, Neurometabolism Unit, Mexico
| | - Lourdes Garza-Ocañas
- Universidad Autonoma de Nuevo Leon, Facultad de Medicina, Department of Pharmacology, Mexico
| | - Alberto Camacho
- Universidad Autónoma de Nuevo Leon, Facultad de Medicina, Biochemistry Department, Mexico; Universidad Autónoma de Nuevo Leon, Centro de Investigación y Desarrollo en Ciencias de la Salud, Neurometabolism Unit, Mexico.
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21
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Rodríguez-Iglesias N, Sierra A, Valero J. Rewiring of Memory Circuits: Connecting Adult Newborn Neurons With the Help of Microglia. Front Cell Dev Biol 2019; 7:24. [PMID: 30891446 PMCID: PMC6411767 DOI: 10.3389/fcell.2019.00024] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 02/08/2019] [Indexed: 12/16/2022] Open
Abstract
New neurons are continuously generated from stem cells and integrated into the adult hippocampal circuitry, contributing to memory function. Several environmental, cellular, and molecular factors regulate the formation of new neurons, but the mechanisms that govern their incorporation into memory circuits are less explored. Herein we will focus on microglia, the resident immune cells of the CNS, which modulate the production of new neurons in the adult hippocampus and are also well suited to participate in their circuit integration. Microglia may contribute to the refinement of brain circuits during development and exert a role in physiological and pathological conditions by regulating axonal and dendritic growth; promoting the formation, elimination, and relocation of synapses; modulating excitatory synaptic maturation; and participating in functional synaptic plasticity. Importantly, microglia are able to sense subtle changes in their environment and may use this information to differently modulate hippocampal wiring, ultimately impacting on memory function. Deciphering the role of microglia in hippocampal circuitry constant rewiring will help to better understand the influence of microglia on memory function.
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Affiliation(s)
- Noelia Rodríguez-Iglesias
- Laboratory of Glial Cell Biology, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Department of Neuroscience, University of the Basque Country UPV/EHU, Leioa, Spain
| | - Amanda Sierra
- Laboratory of Glial Cell Biology, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Department of Neuroscience, University of the Basque Country UPV/EHU, Leioa, Spain.,Ikerbasque Foundation, Bilbao, Spain
| | - Jorge Valero
- Laboratory of Glial Cell Biology, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Department of Neuroscience, University of the Basque Country UPV/EHU, Leioa, Spain.,Ikerbasque Foundation, Bilbao, Spain
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22
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Huart C, Rombaux P, Hummel T. Neural plasticity in developing and adult olfactory pathways – focus on the human olfactory bulb. J Bioenerg Biomembr 2019; 51:77-87. [DOI: 10.1007/s10863-018-9780-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 11/23/2018] [Indexed: 01/18/2023]
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23
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Takahashi H, Yoshihara S, Tsuboi A. The Functional Role of Olfactory Bulb Granule Cell Subtypes Derived From Embryonic and Postnatal Neurogenesis. Front Mol Neurosci 2018; 11:229. [PMID: 30034321 PMCID: PMC6043811 DOI: 10.3389/fnmol.2018.00229] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 06/12/2018] [Indexed: 02/01/2023] Open
Abstract
It has been shown in a variety of mammalian species that sensory experience can regulate the development of various structures, including the retina, cortex, hippocampus, and olfactory bulb (OB). In the mammalian OB, the development of dendrites in excitatory projection neurons, such as mitral and tufted cells, is well known to be dependent on odor experience. Odor experience is also involved in the development of another OB population, a subset of inhibitory interneurons that are generated in the ventricular-subventricular zone throughout life and differentiate into granule cells (GCs) and periglomerular cells. However, the roles that each type of interneuron plays in the control of olfactory behaviors are incompletely understood. We recently found that among the various types of OB interneurons, a subtype of GCs expressing the oncofetal trophoblast glycoprotein 5T4 gene is required for odor detection and discrimination behaviors. Our results suggest that embryonic-born OB interneurons, including 5T4-positive GCs, play a crucial role in fundamental olfactory responses such as simple odor detection and discrimination behaviors. By contrast, postnatal- and adult-born OB interneurons are important in the learning of more complicated olfactory behaviors. Here, we highlight the subtypes of OB GCs, and discuss their roles in olfactory processing and behavior, with a particular focus on the relative contributions of embryonically and postnatally generated subsets of GCs in rodents.
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Affiliation(s)
- Hiroo Takahashi
- Laboratory for the Molecular Biology of Neural Systems, Advanced Medical Research Center, Nara Medical University, Kashihara, Japan
| | - Seiichi Yoshihara
- 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.,Laboratory for the Molecular and Cellular Neuroscience, Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
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24
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The role of calretinin-expressing granule cells in olfactory bulb functions and odor behavior. Sci Rep 2018; 8:9385. [PMID: 29925844 PMCID: PMC6010413 DOI: 10.1038/s41598-018-27692-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 06/08/2018] [Indexed: 12/12/2022] Open
Abstract
The adult mouse olfactory bulb is continuously supplied with new neurons that mostly differentiate into granule cells (GCs). Different subtypes of adult-born GCs have been identified, but their maturational profiles and their roles in bulbar network functioning and odor behavior remain elusive. It is also not known whether the same subpopulations of GCs born during early postnatal life (early-born) or during adulthood (adult-born) differ in their morpho-functional properties. Here, we show that adult-born calretinin-expressing (CR+) and non-expressing (CR−) GCs, as well as early-born CR+ GCs, display distinct inhibitory inputs but indistinguishable excitatory inputs and similar morphological characteristics. The frequencies of inhibitory post-synaptic currents were lower in early-born and adult-born CR+ GCs than in adult-born CR− neurons. These findings were corroborated by the reduced density of gephyrin+ puncta on CR+ GCs. CR+ GCs displayed a higher level of activation following olfactory tasks based on odor discrimination, as determined by an immediate early gene expression analysis. Pharmacogenetic inhibition of CR+ GCs diminished the ability of the mice to discriminate complex odor mixtures. Altogether, our results indicate that distinct inhibitory inputs are received by adult-born CR+ and CR− GCs, that early- and adult-born CR+ neurons have similar morpho-functional properties, and that CR+ GCs are involved in complex odor discrimination tasks.
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25
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Weinhard L, di Bartolomei G, Bolasco G, Machado P, Schieber NL, Neniskyte U, Exiga M, Vadisiute A, Raggioli A, Schertel A, Schwab Y, Gross CT. Microglia remodel synapses by presynaptic trogocytosis and spine head filopodia induction. Nat Commun 2018; 9:1228. [PMID: 29581545 PMCID: PMC5964317 DOI: 10.1038/s41467-018-03566-5] [Citation(s) in RCA: 496] [Impact Index Per Article: 82.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 02/22/2018] [Indexed: 01/09/2023] Open
Abstract
Microglia are highly motile glial cells that are proposed to mediate synaptic pruning during neuronal circuit formation. Disruption of signaling between microglia and neurons leads to an excess of immature synaptic connections, thought to be the result of impaired phagocytosis of synapses by microglia. However, until now the direct phagocytosis of synapses by microglia has not been reported and fundamental questions remain about the precise synaptic structures and phagocytic mechanisms involved. Here we used light sheet fluorescence microscopy to follow microglia–synapse interactions in developing organotypic hippocampal cultures, complemented by a 3D ultrastructural characterization using correlative light and electron microscopy (CLEM). Our findings define a set of dynamic microglia–synapse interactions, including the selective partial phagocytosis, or trogocytosis (trogo-: nibble), of presynaptic structures and the induction of postsynaptic spine head filopodia by microglia. These findings allow us to propose a mechanism for the facilitatory role of microglia in synaptic circuit remodeling and maturation. Direct visualization of microglia-mediated synapse pruning has been lacking. This study shows direct evidence of microglia-synapse interaction where microglia do not necessarily ‘eat’ post-synaptic structure but ‘nibble’ on pre-synaptic terminals, much akin to trogocytosis by lymphocytes.
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Affiliation(s)
- Laetitia Weinhard
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory (EMBL), Via Ramarini 32, 00015, Monterotondo, Italy
| | - Giulia di Bartolomei
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory (EMBL), Via Ramarini 32, 00015, Monterotondo, Italy
| | - Giulia Bolasco
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory (EMBL), Via Ramarini 32, 00015, Monterotondo, Italy
| | - Pedro Machado
- Electron Microscopy Core Facility, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Nicole L Schieber
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Urte Neniskyte
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory (EMBL), Via Ramarini 32, 00015, Monterotondo, Italy.,Department of Neurobiology and Biophysics, Life Science Center, Vilnius University, Sauletekio al. 7, Vilnius, 10257, Lithuania
| | - Melanie Exiga
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory (EMBL), Via Ramarini 32, 00015, Monterotondo, Italy
| | - Auguste Vadisiute
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory (EMBL), Via Ramarini 32, 00015, Monterotondo, Italy.,Department of Neurobiology and Biophysics, Life Science Center, Vilnius University, Sauletekio al. 7, Vilnius, 10257, Lithuania
| | - Angelo Raggioli
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory (EMBL), Via Ramarini 32, 00015, Monterotondo, Italy
| | - Andreas Schertel
- Carl Zeiss Microscopy GmbH, ZEISS Group, Carl-Zeiss-Strasse 22, 73447, Oberkochen, Germany
| | - Yannick Schwab
- Electron Microscopy Core Facility, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117, Heidelberg, Germany.,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Cornelius T Gross
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory (EMBL), Via Ramarini 32, 00015, Monterotondo, Italy.
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Abstract
Odor–reward association during appetitive learning is a fundamental process that requires multiple forms of plasticity. In the adult olfactory bulb, the continual production of newborn interneurons contributes to the functional plasticity of the system, placing the newcomers in a key position to participate in olfactory associative learning. Here, we demonstrate that adult-born neurons, but not preexisting ones, contain information about learned positive value. Moreover, specific heightening of this signal improves associative learning and odor value update and is enough in some cases to trigger behavior even without odor stimulus. Collectively, our findings show an important role of this adult-born interneuron population in odor–reward association and unveil the relevance of odor value encoding at early stages of sensory processing. Olfaction is an important sensory modality driving fundamental behaviors. During odor-dependent learning, a positive value is commonly assigned to an odorant, and multiple forms of plasticity are involved when such odor–reward associations are formed. In rodents, one of the mechanisms underlying plasticity in the olfactory bulb consists in recruiting new neurons daily throughout life. However, it is still unknown whether adult-born neurons might participate in encoding odor value. Here, we demonstrate that exposure to reward-associated odors specifically increases activity of adult-born neurons but not preexisting neurons. Remarkably, adult-born neuron activation during rewarded odor presentation heightens discrimination learning and enhances the ability to update the odor value during reversal association. Moreover, in some cases, activation of this interneuron population can trigger olfactory learning without sensory stimulation. Taken together, our results show a specific involvement of adult-born neurons in facilitating odor–reward association during adaptive learning.
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27
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POU6f1 Mediates Neuropeptide-Dependent Plasticity in the Adult Brain. J Neurosci 2018; 38:1443-1461. [PMID: 29305536 DOI: 10.1523/jneurosci.1641-17.2017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 12/11/2017] [Accepted: 12/21/2017] [Indexed: 01/20/2023] Open
Abstract
The mouse olfactory bulb (OB) features continued, activity-dependent integration of adult-born neurons, providing a robust model with which to examine mechanisms of plasticity in the adult brain. We previously reported that local OB interneurons secrete the neuropeptide corticotropin-releasing hormone (CRH) in an activity-dependent manner onto adult-born granule neurons and that local CRH signaling promotes expression of synaptic machinery in the bulb. This effect is mediated via activation of the CRH receptor 1 (CRHR1), which is developmentally regulated during adult-born neuron maturation. CRHR1 is a GS-protein-coupled receptor that activates CREB-dependent transcription in the presence of CRH. Therefore, we hypothesized that locally secreted CRH activates CRHR1 to initiate circuit plasticity programs. To identify such programs, we profiled gene expression changes associated with CRHR1 activity in adult-born neurons of the OB. Here, we show that CRHR1 activity influences expression of the brain-specific Homeobox-containing transcription factor POU Class 6 Homeobox 1 (POU6f1). To elucidate the contributions of POU6f1 toward activity-dependent circuit remodeling, we targeted CRHR1+ neurons in male and female mice for cell-type-specific manipulation of POU6f1 expression. Whereas loss of POU6f1 in CRHR1+ neurons resulted in reduced dendritic complexity and decreased synaptic connectivity, overexpression of POU6f1 in CRHR1+ neurons promoted dendritic outgrowth and branching and influenced synaptic function. Together, these findings suggest that the transcriptional program directed by POU6f1 downstream of local CRH signaling in adult-born neurons influences circuit dynamics in response to activity-dependent peptide signaling in the adult brain.SIGNIFICANCE STATEMENT Elucidating mechanisms of plasticity in the adult brain is helpful for devising strategies to understand and treat neurodegeneration. Circuit plasticity in the adult mouse olfactory bulb is exemplified by both continued cell integration and synaptogenesis. We previously reported that these processes are influenced by local neuropeptide signaling in an activity-dependent manner. Here, we show that local corticotropin-releasing hormone (CRH) signaling induces dynamic gene expression changes in CRH receptor expressing adult-born neurons, including altered expression of the transcription factor POU6f1 We further show that POU6f1 is necessary for proper dendrite specification and patterning, as well as synapse development and function in adult-born neurons. Together, these findings reveal a novel mechanism by which peptide signaling modulates adult brain circuit plasticity.
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28
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Reshef R, Kudryavitskaya E, Shani-Narkiss H, Isaacson B, Rimmerman N, Mizrahi A, Yirmiya R. The role of microglia and their CX3CR1 signaling in adult neurogenesis in the olfactory bulb. eLife 2017; 6. [PMID: 29251592 PMCID: PMC5734876 DOI: 10.7554/elife.30809] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 12/05/2017] [Indexed: 01/09/2023] Open
Abstract
Microglia play important roles in perinatal neuro- and synapto-genesis. To test the role of microglia in these processes during adulthood, we examined the effects of microglia depletion, via treatment of mice with the CSF-1 receptor antagonist PLX5622, and abrogated neuronal-microglial communication in CX3C receptor-1 deficient (Cx3cr1−/−) mice. Microglia depletion significantly lowered spine density in young (developing) but not mature adult-born-granule-cells (abGCs) in the olfactory bulb. Two-photon time-lapse imaging indicated that microglia depletion reduced spine formation and elimination. Functionally, odor-evoked responses of mitral cells, which are normally inhibited by abGCs, were increased in microglia-depleted mice. In Cx3cr1−/− mice, abGCs exhibited reduced spine density, dynamics and size, concomitantly with reduced contacts between Cx3cr1-deficient microglia and abGCs' dendritic shafts, along with increased proportion of microglia-contacted spines. Thus, during adult neurogenesis, microglia regulate the elimination (pruning), formation, and maintenance of synapses on newborn neurons, contributing to the functional integrity of the olfactory bulb circuitry.
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Affiliation(s)
- Ronen Reshef
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Elena Kudryavitskaya
- Department of Neurobiology, Institute for Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel.,The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Haran Shani-Narkiss
- Department of Neurobiology, Institute for Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel.,The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Batya Isaacson
- Department of Immunology and Cancer Research, The Lautenberg Center for General and Tumor Immunology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Neta Rimmerman
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Adi Mizrahi
- Department of Neurobiology, Institute for Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel.,The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Raz Yirmiya
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
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Malvaut S, Gribaudo S, Hardy D, David LS, Daroles L, Labrecque S, Lebel-Cormier MA, Chaker Z, Coté D, De Koninck P, Holzenberger M, Trembleau A, Caille I, Saghatelyan A. CaMKIIα Expression Defines Two Functionally Distinct Populations of Granule Cells Involved in Different Types of Odor Behavior. Curr Biol 2017; 27:3315-3329.e6. [PMID: 29107547 DOI: 10.1016/j.cub.2017.09.058] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 08/23/2017] [Accepted: 09/27/2017] [Indexed: 12/25/2022]
Abstract
Granule cells (GCs) in the olfactory bulb (OB) play an important role in odor information processing. Although they have been classified into various neurochemical subtypes, the functional roles of these subtypes remain unknown. We used in vivo two-photon Ca2+ imaging combined with cell-type-specific identification of GCs in the mouse OB to examine whether functionally distinct GC subtypes exist in the bulbar network. We showed that half of GCs express Ca2+/calmodulin-dependent protein kinase IIα (CaMKIIα+) and that these neurons are preferentially activated by olfactory stimulation. The higher activity of CaMKIIα+ neurons is due to the weaker inhibitory input that they receive compared to their CaMKIIα-immunonegative (CaMKIIα-) counterparts. In line with these functional data, immunohistochemical analyses showed that 75%-90% of GCs expressing the immediate early gene cFos are CaMKIIα+ in naive animals and in mice that have been exposed to a novel odor and go/no-go operant conditioning, or that have been subjected to long-term associative memory and spontaneous habituation/dishabituation odor discrimination tasks. On the other hand, a perceptual learning task resulted in increased activation of CaMKIIα- cells. Pharmacogenetic inhibition of CaMKIIα+ GCs revealed that this subtype is involved in habituation/dishabituation and go/no-go odor discrimination, but not in perceptual learning. In contrast, pharmacogenetic inhibition of GCs in a subtype-independent manner affected perceptual learning. Our results indicate that functionally distinct populations of GCs exist in the OB and that they play distinct roles during different odor tasks.
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Affiliation(s)
- Sarah Malvaut
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada
| | - Simona Gribaudo
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, 75005 Paris, France
| | - Delphine Hardy
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada
| | | | - Laura Daroles
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, 75005 Paris, France
| | - Simon Labrecque
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada
| | | | - Zayna Chaker
- INSERM and Sorbonne Universités, UPMC, Centre de Recherche Saint-Antoine, Paris, France
| | - Daniel Coté
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada; Faculté des Sciences et de Génie, Université Laval, Quebec City, QC G1V 0A6, Canada
| | - Paul De Koninck
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada; Faculté des Sciences et de Génie, Université Laval, Quebec City, QC G1V 0A6, Canada
| | - Martin Holzenberger
- INSERM and Sorbonne Universités, UPMC, Centre de Recherche Saint-Antoine, Paris, France
| | - Alain Trembleau
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, 75005 Paris, France
| | - Isabelle Caille
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, 75005 Paris, France; Université Paris Diderot, Sorbonne Paris Cité, 75013 Paris, France.
| | - Armen Saghatelyan
- CERVO Brain Research Center, Quebec City, QC G1J 2G3, Canada; Department of Psychiatry and Neuroscience, Université Laval, Quebec City, QC G1V 0A6, Canada.
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30
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Hardy D, Saghatelyan A. Different forms of structural plasticity in the adult olfactory bulb. NEUROGENESIS 2017; 4:e1301850. [PMID: 28596977 DOI: 10.1080/23262133.2017.1301850] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 02/24/2017] [Accepted: 02/27/2017] [Indexed: 12/26/2022]
Abstract
The adult olfactory bulb (OB) continuously receives new interneurons that integrate into the functional neuronal network and that play an important role in odor information processing and olfactory behavior. Adult neuronal progenitors are derived from neural stem cells in the subventricular zone (SVZ) bordering the lateral ventricle. They migrate long distances along the rostral migratory stream (RMS) toward the OB where they differentiate into interneurons, mature, and establish synapses with tufted or mitral cells (MC), the principal neurons in the OB. The plasticity provided by both adult-born and pre-existing early-born neurons depends on the formation and pruning of new synaptic contacts that adapt the functioning of the bulbar network to changing environmental conditions. However, the formation of new synapses occurs over a long time scale (hours-days), whereas some changes in environmental conditions can occur more rapidly, requiring a much faster adjustment of neuronal networks. A new form of structural remodeling of adult-born, but not early-born, neurons was recently brought to light. This plasticity, which is based on the activity-dependent relocation of mature spines of GCs toward the dendrites of active principal cells, may allow a more rapid adjustment of the neuronal network in response to quick and persistent changes in sensory inputs. In this mini-review we discuss the different forms of structural plasticity displayed by adult-born and early-born neurons and the possibility that these different forms of structural remodeling may fulfill distinct roles in odor information processing.
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Affiliation(s)
- Delphine Hardy
- Cellular Neurobiology Unit, Centre de Recherche de l'Institut Universitaire en Santé Mentale de Québec, Quebec City, QC, Canada
| | - Armen Saghatelyan
- Cellular Neurobiology Unit, Centre de Recherche de l'Institut Universitaire en Santé Mentale de Québec, Quebec City, QC, Canada.,Department of Psychiatry and Neuroscience, Université Laval, Quebec City, QC, Canada
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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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Sailor KA, Schinder AF, Lledo PM. Adult neurogenesis beyond the niche: its potential for driving brain plasticity. Curr Opin Neurobiol 2016; 42:111-117. [PMID: 28040643 DOI: 10.1016/j.conb.2016.12.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 11/30/2016] [Accepted: 12/05/2016] [Indexed: 12/14/2022]
Abstract
Adult neurogenesis emerges as a tremendous form of plasticity with the continuous addition and loss of neurons in the adult brain. It is unclear how preexisting adult circuits generated during development are capable of modifying existing connections to accommodate the thousands of new synapses formed and exchanged each day. Here we first make parallels with sensory deprivation studies and its ability to induce preexisting non-neurogenic adult circuits to undergo massive reorganization. We then review recent studies that show high structural and synaptic plasticity in circuits directly connected to adult-born neurons. Finally, we propose future directions in the field to decipher how host circuits can accommodate new neuron integration and to determine the impact of adult neurogenesis on global brain plasticity.
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Affiliation(s)
- Kurt A Sailor
- Laboratory for Perception and Memory, Pasteur Institute, F-75015 Paris, France; Centre National de la Recherche Scientifique (CNRS), Unité de Recherche Associée (UMR3571), F-75015 Paris, France
| | - Alejandro F Schinder
- Laboratory of Neuronal Plasticity, Leloir Institute (IIBBA - CONICET), Av. Patricias Argentinas 435, Buenos Aires C1405BWE, Argentina
| | - Pierre-Marie Lledo
- Laboratory for Perception and Memory, Pasteur Institute, F-75015 Paris, France; Centre National de la Recherche Scientifique (CNRS), Unité de Recherche Associée (UMR3571), F-75015 Paris, France.
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