151
|
Rantamäki T, Kohtala S. Encoding, Consolidation, and Renormalization in Depression: Synaptic Homeostasis, Plasticity, and Sleep Integrate Rapid Antidepressant Effects. Pharmacol Rev 2020; 72:439-465. [DOI: 10.1124/pr.119.018697] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
|
152
|
Activity Dependent and Independent Determinants of Synaptic Size Diversity. J Neurosci 2020; 40:2828-2848. [PMID: 32127494 DOI: 10.1523/jneurosci.2181-19.2020] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 02/04/2020] [Accepted: 02/13/2020] [Indexed: 11/21/2022] Open
Abstract
The extraordinary diversity of excitatory synapse sizes is commonly attributed to activity-dependent processes that drive synaptic growth and diminution. Recent studies also point to activity-independent size fluctuations, possibly driven by innate synaptic molecule dynamics, as important generators of size diversity. To examine the contributions of activity-dependent and independent processes to excitatory synapse size diversity, we studied glutamatergic synapse size dynamics and diversification in cultured rat cortical neurons (both sexes), silenced from plating. We found that in networks with no history of activity whatsoever, synaptic size diversity was no less extensive than that observed in spontaneously active networks. Synapses in silenced networks were larger, size distributions were broader, yet these were rightward-skewed and similar in shape when scaled by mean synaptic size. Silencing reduced the magnitude of size fluctuations and weakened constraints on size distributions, yet these were sufficient to explain synaptic size diversity in silenced networks. Model-based exploration followed by experimental testing indicated that silencing-associated changes in innate molecular dynamics and fluctuation characteristics might negatively impact synaptic persistence, resulting in reduced synaptic numbers. This, in turn, would increase synaptic molecule availability, promote synaptic enlargement, and ultimately alter fluctuation characteristics. These findings suggest that activity-independent size fluctuations are sufficient to fully diversify glutamatergic synaptic sizes, with activity-dependent processes primarily setting the scale rather than the shape of size distributions. Moreover, they point to reciprocal relationships between synaptic size fluctuations, size distributions, and synaptic numbers mediated by the innate dynamics of synaptic molecules as they move in, out, and between synapses.SIGNIFICANCE STATEMENT Sizes of glutamatergic synapses vary tremendously, even when formed on the same neuron. This diversity is commonly thought to reflect the outcome of activity-dependent forms of synaptic plasticity, yet activity-independent processes might also play some part. Here we show that in neurons with no history of activity whatsoever, synaptic sizes are no less diverse. We show that this diversity is the product of activity-independent size fluctuations, which are sufficient to generate a full repertoire of synaptic sizes at correct proportions. By combining modeling and experimentation we expose reciprocal relationships between size fluctuations, synaptic sizes and synaptic counts, and show how these phenomena might be connected through the dynamics of synaptic molecules as they move in, out, and between synapses.
Collapse
|
153
|
Involvement of CX3CL1/CX3CR1 in depression and cognitive impairment induced by chronic unpredictable stress and relevant underlying mechanism. Behav Brain Res 2020; 381:112371. [DOI: 10.1016/j.bbr.2019.112371] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 11/15/2019] [Accepted: 11/19/2019] [Indexed: 02/07/2023]
|
154
|
Sun YY, Zhu L, Sun ZL, Feng DF. CRMP2 improves memory deficits by enhancing the maturation of neuronal dendritic spines after traumatic brain injury. Exp Neurol 2020; 328:113253. [PMID: 32084454 DOI: 10.1016/j.expneurol.2020.113253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 02/12/2020] [Accepted: 02/17/2020] [Indexed: 11/28/2022]
Abstract
Our recent study investigated the role of collapsin response mediator protein-2 (CRMP2) on dendritic spine morphology and memory function after traumatic brain injury (TBI). First, we examined the density and morphology of dendritic spines in Thy1-GFP mice on the 1 st day (P1D) and 7th day (P7D) after controlled cortical impact injury (CCI). The dendritic spine density in the hippocampus was decreased on P1D, in which mainly mushroom-type and thin-type spines were lost. The density of dendritic spines was increased on P7D, most of which were of the thin type. Next, we explored the expression of CRMP2 on P1D and P7D. CRMP2 expression was decreased on P1D, but the levels of the CRMP2 breakdown product were increased. On P7D, the expression pattern was the opposite. Then, we constructed CRMP2 overexpression and knockdown plasmids and transfected them into cultured neurons in vitro. CRMP2 increased the dendritic spine density of cultured neurons and the proportion of mushroom-type spines, while CRMP2-shRNA reduced the dendritic spine density and the proportion of mushroom-type spines. To determine the role of CRMP2 in dendritic spines after TBI, we stereotactically injected the CRMP2 overexpression and knockdown viruses into the hippocampus and found that CRMP2 increased the dendritic spine density and the proportion of mushroom-type spines after TBI. Meanwhile, as suggested by the morphological changes, fear conditioning behavioral experiments confirmed that CRMP2 improved memory deficits after TBI.
Collapse
Affiliation(s)
- Yi-Yu Sun
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China
| | - Liang Zhu
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China
| | - Zhao-Liang Sun
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China
| | - Dong-Fu Feng
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China; Institute of Traumatic Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China.
| |
Collapse
|
155
|
Lee CR, Najafizadeh L, Margolis DJ. Investigating learning-related neural circuitry with chronic in vivo optical imaging. Brain Struct Funct 2020; 225:467-480. [PMID: 32006147 DOI: 10.1007/s00429-019-02001-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 12/05/2019] [Indexed: 10/25/2022]
Abstract
Fundamental aspects of brain function, including development, plasticity, learning, and memory, can take place over time scales of days to years. Chronic in vivo imaging of neural activity with cellular resolution is a powerful method for tracking the long-term activity of neural circuits. We review recent advances in our understanding of neural circuit function from diverse brain regions that have been enabled by chronic in vivo cellular imaging. Insight into the neural basis of learning and decision-making, in particular, benefit from the ability to acquire longitudinal data from genetically identified neuronal populations, deep brain areas, and subcellular structures. We propose that combining chronic imaging with further experimental and computational innovations will advance our understanding of the neural circuit mechanisms of brain function.
Collapse
Affiliation(s)
- Christian R Lee
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Laleh Najafizadeh
- Department of Electrical and Computer Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - David J Margolis
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA.
| |
Collapse
|
156
|
Pan Y, Monje M. Activity Shapes Neural Circuit Form and Function: A Historical Perspective. J Neurosci 2020; 40:944-954. [PMID: 31996470 PMCID: PMC6988998 DOI: 10.1523/jneurosci.0740-19.2019] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 12/07/2019] [Accepted: 12/10/2019] [Indexed: 12/30/2022] Open
Abstract
The brilliant and often prescient hypotheses of Ramon y Cajal have proven foundational for modern neuroscience, but his statement that "In adult centers the nerve paths are something fixed, ended, immutable … " is an exception that did not stand the test of empirical study. Mechanisms of cellular and circuit-level plasticity continue to shape and reshape many regions of the adult nervous system long after the neurodevelopmental period. Initially focused on neurons alone, the field has followed a meteoric trajectory in understanding of activity-regulated neurodevelopment and ongoing neuroplasticity with an arc toward appreciating neuron-glial interactions and the role that each neural cell type plays in shaping adaptable neural circuity. In this review, as part of a celebration of the 50th anniversary of Society for Neuroscience, we provide a historical perspective, following this arc of inquiry from neuronal to neuron-glial mechanisms by which activity and experience modulate circuit structure and function. The scope of this consideration is broad, and it will not be possible to cover the wealth of knowledge about all aspects of activity-dependent circuit development and plasticity in depth.
Collapse
Affiliation(s)
- Yuan Pan
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, California 94305
| | - Michelle Monje
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, California 94305
| |
Collapse
|
157
|
Hirbec H, Déglon N, Foo LC, Goshen I, Grutzendler J, Hangen E, Kreisel T, Linck N, Muffat J, Regio S, Rion S, Escartin C. Emerging technologies to study glial cells. Glia 2020; 68:1692-1728. [PMID: 31958188 DOI: 10.1002/glia.23780] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 12/20/2019] [Accepted: 12/23/2019] [Indexed: 12/11/2022]
Abstract
Development, physiological functions, and pathologies of the brain depend on tight interactions between neurons and different types of glial cells, such as astrocytes, microglia, oligodendrocytes, and oligodendrocyte precursor cells. Assessing the relative contribution of different glial cell types is required for the full understanding of brain function and dysfunction. Over the recent years, several technological breakthroughs were achieved, allowing "glio-scientists" to address new challenging biological questions. These technical developments make it possible to study the roles of specific cell types with medium or high-content workflows and perform fine analysis of their mutual interactions in a preserved environment. This review illustrates the potency of several cutting-edge experimental approaches (advanced cell cultures, induced pluripotent stem cell (iPSC)-derived human glial cells, viral vectors, in situ glia imaging, opto- and chemogenetic approaches, and high-content molecular analysis) to unravel the role of glial cells in specific brain functions or diseases. It also illustrates the translation of some techniques to the clinics, to monitor glial cells in patients, through specific brain imaging methods. The advantages, pitfalls, and future developments are discussed for each technique, and selected examples are provided to illustrate how specific "gliobiological" questions can now be tackled.
Collapse
Affiliation(s)
- Hélène Hirbec
- Institute for Functional Genomics (IGF), University of Montpellier, CNRS, INSERM, Montpellier, France
| | - Nicole Déglon
- Laboratory of Neurotherapies and Neuromodulation, Department of Clinical Neuroscience, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland.,Laboratory of Neurotherapies and Neuromodulation, Neuroscience Research Center, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Lynette C Foo
- Neuroimmunology and Neurodegeneration Section, The Neuroscience and Rare Diseases Discovery and Translational Area, F. Hoffman-La Roche, Basel, Switzerland
| | - Inbal Goshen
- Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Jaime Grutzendler
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, USA.,Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Emilie Hangen
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Département de la Recherche Fondamentale, Institut de Biologie François Jacob, MIRCen, Fontenay-aux-Roses, France.,Centre National de la Recherche Scientifique, Neurodegenerative Diseases Laboratory, Université Paris-Sud, Université Paris-Saclay, UMR 9199, Fontenay-aux-Roses, France
| | - Tirzah Kreisel
- Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Nathalie Linck
- Institute for Functional Genomics (IGF), University of Montpellier, CNRS, INSERM, Montpellier, France
| | - Julien Muffat
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, and Department of Molecular Genetics, The University of Toronto, Toronto, Canada
| | - Sara Regio
- Laboratory of Neurotherapies and Neuromodulation, Department of Clinical Neuroscience, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland.,Laboratory of Neurotherapies and Neuromodulation, Neuroscience Research Center, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Sybille Rion
- Neuroimmunology and Neurodegeneration Section, The Neuroscience and Rare Diseases Discovery and Translational Area, F. Hoffman-La Roche, Basel, Switzerland
| | - Carole Escartin
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Département de la Recherche Fondamentale, Institut de Biologie François Jacob, MIRCen, Fontenay-aux-Roses, France.,Centre National de la Recherche Scientifique, Neurodegenerative Diseases Laboratory, Université Paris-Sud, Université Paris-Saclay, UMR 9199, Fontenay-aux-Roses, France
| |
Collapse
|
158
|
Anderson RM, Johnson SB, Lingg RT, Hinz DC, Romig-Martin SA, Radley JJ. Evidence for Similar Prefrontal Structural and Functional Alterations in Male and Female Rats Following Chronic Stress or Glucocorticoid Exposure. Cereb Cortex 2020; 30:353-370. [PMID: 31184364 PMCID: PMC7029687 DOI: 10.1093/cercor/bhz092] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 04/01/2019] [Accepted: 04/08/2019] [Indexed: 12/28/2022] Open
Abstract
Previous work of ours and others has documented regressive changes in neuronal architecture and function in the medial prefrontal cortex (mPFC) of male rats following chronic stress. As recent focus has shifted toward understanding whether chronic stress effects on mPFC are sexually dimorphic, here we undertake a comprehensive analysis to address this issue. First, we show that chronic variable stress (14-day daily exposure to different challenges) resulted in a comparable degree of adrenocortical hyperactivity, working memory impairment, and dendritic spine loss in mPFC pyramidal neurons in both sexes. Next, exposure of female rats to 21-day regimen of corticosterone resulted in a similar pattern of mPFC dendritic spine attrition and increase in spine volume. Finally, we examined the effects of another widely used regimen, chronic restraint stress (CRS, 21-day of daily 6-h restraint), on dendritic spine changes in mPFC in both sexes. CRS resulted in response decrements in adrenocortical output (habituation), and induced a pattern of consistent, but less widespread, dendritic spine loss similar to the foregoing challenges. Our data suggest that chronic stress or glucocorticoid exposure induces a relatively undifferentiated pattern of structural and functional alterations in mPFC in both males and females.
Collapse
Affiliation(s)
- Rachel M Anderson
- Department of Psychological and Brain Sciences, Program in Neuroscience, Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
| | - Shane B Johnson
- Department of Psychological and Brain Sciences, Program in Neuroscience, Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
| | - Ryan T Lingg
- Department of Psychological and Brain Sciences, Program in Neuroscience, Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
| | - Dalton C Hinz
- Department of Psychological and Brain Sciences, Program in Neuroscience, Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
| | - Sara A Romig-Martin
- Department of Psychological and Brain Sciences, Program in Neuroscience, Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
| | - Jason J Radley
- Department of Psychological and Brain Sciences, Program in Neuroscience, Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
| |
Collapse
|
159
|
Sanculi D, Pannoni KE, Bushong EA, Crump M, Sung M, Popat V, Zaher C, Hicks E, Song A, Mofakham N, Li P, Antzoulatos EG, Fioravante D, Ellisman MH, DeBello WM. Toric Spines at a Site of Learning. eNeuro 2020; 7:ENEURO.0197-19.2019. [PMID: 31822521 PMCID: PMC6944481 DOI: 10.1523/eneuro.0197-19.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 10/23/2019] [Accepted: 11/02/2019] [Indexed: 11/21/2022] Open
Abstract
We discovered a new type of dendritic spine. It is found on space-specific neurons in the barn owl inferior colliculus, a site of experience-dependent plasticity. Connectomic analysis revealed dendritic protrusions of unusual morphology including topological holes, hence termed "toric" spines (n = 76). More significantly, presynaptic terminals converging onto individual toric spines displayed numerous active zones (up to 49) derived from multiple axons (up to 11) with incoming trajectories distributed widely throughout 3D space. This arrangement is suited to integrate input sources. Dense reconstruction of two toric spines revealed that they were unconnected with the majority (∼84%) of intertwined axons, implying a high capacity for information storage. We developed an ex vivo slice preparation and provide the first published data on space-specific neuron intrinsic properties, including cellular subtypes with and without toric-like spines. We propose that toric spines are a cellular locus of sensory integration and behavioral learning.
Collapse
Affiliation(s)
- Daniel Sanculi
- Center for Neuroscience, University of California, Davis, CA 95618
| | | | - Eric A Bushong
- National Center for Molecular Imaging Research, University of California, La Jolla, CA 92093
| | - Michael Crump
- Center for Neuroscience, University of California, Davis, CA 95618
| | - Michelle Sung
- Center for Neuroscience, University of California, Davis, CA 95618
| | - Vyoma Popat
- Center for Neuroscience, University of California, Davis, CA 95618
| | - Camilia Zaher
- Center for Neuroscience, University of California, Davis, CA 95618
| | - Emma Hicks
- Center for Neuroscience, University of California, Davis, CA 95618
| | - Ashley Song
- Center for Neuroscience, University of California, Davis, CA 95618
| | - Nikan Mofakham
- Center for Neuroscience, University of California, Davis, CA 95618
| | - Peining Li
- Center for Neuroscience, University of California, Davis, CA 95618
| | | | | | - Mark H Ellisman
- National Center for Molecular Imaging Research, University of California, La Jolla, CA 92093
| | | |
Collapse
|
160
|
Cisneros-Franco JM, Voss P, Thomas ME, de Villers-Sidani E. Critical periods of brain development. HANDBOOK OF CLINICAL NEUROLOGY 2020; 173:75-88. [PMID: 32958196 DOI: 10.1016/b978-0-444-64150-2.00009-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Brain plasticity is maximal at specific time windows during early development known as critical periods (CPs), during which sensory experience is necessary to establish optimal cortical representations of the surrounding environment. After CP closure, a range of functional and structural elements prevent passive experience from eliciting significant plastic changes in the brain. The transition from a plastic to a more fixed state is advantageous as it allows for the sequential consolidation and retention of new and more complex perceptual, motor, and cognitive functions. However, the formation of stable neural representations may pose limitations on future revisions to the circuitry. If sensory experience is abnormal or absent during this time, it can have profound effects on sensory representations in adulthood, resulting in quasi-permanent adaptations that can make it nearly impossible to learn certain skills or process certain stimulus properties later on in life. This chapter begins with a brief introduction to experience-dependent plasticity throughout the lifespan (Section Introduction). Next, we define what constitutes a CP (Section What Are Critical Periods?) and review some of the key CPs in the visual and auditory systems (Section Key Critical Periods of Sensory Systems). We then discuss the mechanisms whereby cortical plasticity is regulated both locally and through neuromodulatory systems (Section How Are Critical Periods Regulated?). Finally, we highlight studies showing that CPs can be extended beyond their normal epochs, closed prematurely, or reopened during adult life by merely altering sensory inputs (Section Timing of Critical Periods: Can CP Plasticity Be Extended, Limited, or Reactivated?).
Collapse
Affiliation(s)
- J Miguel Cisneros-Franco
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada; Centre for Research on Brain, Language and Music, McGill University, Montreal, QC, Canada
| | - Patrice Voss
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada; Centre for Research on Brain, Language and Music, McGill University, Montreal, QC, Canada
| | - Maryse E Thomas
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada; Centre for Research on Brain, Language and Music, McGill University, Montreal, QC, Canada
| | - Etienne de Villers-Sidani
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada; Centre for Research on Brain, Language and Music, McGill University, Montreal, QC, Canada.
| |
Collapse
|
161
|
Parra A, Baker CA, Bolton MM. Regional Specialization of Pyramidal Neuron Morphology and Physiology in the Tree Shrew Neocortex. Cereb Cortex 2019; 29:4488-4505. [PMID: 30715235 DOI: 10.1093/cercor/bhy326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 10/12/2018] [Accepted: 12/07/2018] [Indexed: 01/08/2023] Open
Abstract
The mammalian cerebral cortex is divided into different areas according to their function and pattern of connections. Studies comparing primary visual (V1) and prefrontal cortex (PFC) of primates have demonstrated striking pyramidal neuron (PN) specialization not present in comparable areas of the mouse neocortex. To better understand PFC evolution and regional PN specialization, we studied the tree shrew, a species with a close phylogenetic relationship to primates. We defined the tree shrew PFC based on cytoarchitectonic borders, thalamic connectivity and characterized the morphology and electrophysiology of layer II/III PNs in V1 and PFC. Similar to primates, the PFC PNs in the tree shrew fire with a regular spiking pattern and have larger dendritic tree and spines than those in V1. However, V1 PNs showed strikingly large basal dendritic arbors with high spine density, firing at higher rates and in a more varied pattern than PFC PNs. Yet, unlike in the mouse and unreported in the primate, medial prefrontal PN are more easily recruited than either the dorsolateral or V1 neurons. This specialization of PN morphology and physiology is likely to be a significant factor in the evolution of cortex, contributing to differences in the computational capacities of individual cortical areas.
Collapse
Affiliation(s)
- Andres Parra
- Disorders of Neural Circuit Function, Max Planck Florida Institute for Neuroscience, Jupiter, USA.,Functional Architecture of the Cerebral Cortex, Max Planck Florida Institute for Neuroscience, Jupiter, USA.,Cellular and Systems Neurobiology, Instituto de Neurociencias de Alicante, Alicante, Spain
| | - Christopher A Baker
- Disorders of Neural Circuit Function, Max Planck Florida Institute for Neuroscience, Jupiter, USA
| | - M McLean Bolton
- Disorders of Neural Circuit Function, Max Planck Florida Institute for Neuroscience, Jupiter, USA
| |
Collapse
|
162
|
Hinkle JJ, Olschowka JA, Love TM, Williams JP, O'Banion MK. Cranial irradiation mediated spine loss is sex-specific and complement receptor-3 dependent in male mice. Sci Rep 2019; 9:18899. [PMID: 31827187 PMCID: PMC6906384 DOI: 10.1038/s41598-019-55366-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 11/27/2019] [Indexed: 12/14/2022] Open
Abstract
Cranial irradiation is the main therapeutic treatment for primary and metastatic malignancies in the brain. However, cranial radiation therapy produces long-term impairment in memory, information processing, and attention that contribute to a decline in quality of life. The hippocampal neural network is fundamental for proper storage and retrieval of episodic and spatial memories, suggesting that hippocampal signaling dysfunction could be responsible for the progressive memory deficits observed following irradiation. Previous rodent studies demonstrated that irradiation induces significant loss in dendritic spine number, alters spine morphology, and is associated with behavioral task deficits. Additionally, the literature suggests a common mechanism in which synaptic elimination via microglial-mediated phagocytosis is complement dependent and associated with cognitive impairment in aging as well as disease. We demonstrate sexual dimorphisms in irradiation-mediated alterations of microglia activation markers and dendritic spine density. Further, we find that the significant dendritic spine loss observed in male mice following irradiation is microglia complement receptor 3 (CR3)-dependent. By identifying sex-dependent cellular and molecular factors underlying irradiation-mediated spine loss, therapies can be developed to counteract irradiation-induced cognitive decline and improve patient quality of life.
Collapse
Affiliation(s)
- Joshua J Hinkle
- Department of Neuroscience and Del Monte Neuroscience Institute, University of Rochester School of Medicine & Dentistry, Rochester, New York, 14642, USA
| | - John A Olschowka
- Department of Neuroscience and Del Monte Neuroscience Institute, University of Rochester School of Medicine & Dentistry, Rochester, New York, 14642, USA
| | - Tanzy M Love
- Department of Biostatistics and Computational Biology, University of Rochester School of Medicine & Dentistry, Rochester, New York, 14642, USA
| | - Jacqueline P Williams
- Department of Environmental Medicine, University of Rochester School of Medicine & Dentistry, Rochester, New York, 14642, USA
| | - M Kerry O'Banion
- Department of Neuroscience and Del Monte Neuroscience Institute, University of Rochester School of Medicine & Dentistry, Rochester, New York, 14642, USA. .,Department of Neurology, University of Rochester School of Medicine & Dentistry, Rochester, New York, 14642, USA.
| |
Collapse
|
163
|
Ocular Dominance Plasticity in Binocular Primary Visual Cortex Does Not Require C1q. J Neurosci 2019; 40:769-783. [PMID: 31801811 DOI: 10.1523/jneurosci.1011-19.2019] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 10/21/2019] [Accepted: 10/23/2019] [Indexed: 11/21/2022] Open
Abstract
C1q, the initiator of the classical complement cascade, mediates synapse elimination in the postnatal mouse dorsolateral geniculate nucleus of the thalamus and sensorimotor cortex. Here, we asked whether C1q plays a role in experience-dependent synaptic refinement in the visual system at later stages of development. The binocular zone of primary visual cortex (V1b) undergoes spine loss and changes in neuronal responsiveness following the closure of one eye during a defined critical period [a process referred to as ocular dominance plasticity (ODP)]. We therefore hypothesized that ODP would be impaired in the absence of C1q, and that V1b development would also be abnormal without C1q-mediated synapse elimination. However, when we examined several features of V1b development in mice lacking C1q, we found that the densities of most spine populations on basal and proximal apical dendrites, as well as firing rates and ocular dominance, were normal. C1q was only transiently required for the development of spines on apical, but not basal, secondary dendrites. Dendritic morphologies were also unaffected. Although we did not observe the previously described spine loss during ODP in either genotype, our results reveal that the animals lacking C1q had normal shifts in neuronal responsiveness following eye closure. Experiments were performed in both male and female mice. These results suggest that the development and plasticity of the mouse V1b is grossly normal in the absence of C1q.SIGNIFICANCE STATEMENT These findings illustrate that the development and experience-dependent plasticity of V1b is mostly normal in the absence of C1q, even though C1q has previously been shown to be required for developmental synapse elimination in the mouse visual thalamus as well as sensorimotor cortex. The V1b phenotypes in mice lacking C1q are more similar to the mild defects previously observed in the hippocampus of these mice, emphasizing that the contribution of C1q to synapse elimination appears to be dependent on context.
Collapse
|
164
|
Linaro D, Vermaercke B, Iwata R, Ramaswamy A, Libé-Philippot B, Boubakar L, Davis BA, Wierda K, Davie K, Poovathingal S, Penttila PA, Bilheu A, De Bruyne L, Gall D, Conzelmann KK, Bonin V, Vanderhaeghen P. Xenotransplanted Human Cortical Neurons Reveal Species-Specific Development and Functional Integration into Mouse Visual Circuits. Neuron 2019; 104:972-986.e6. [PMID: 31761708 PMCID: PMC6899440 DOI: 10.1016/j.neuron.2019.10.002] [Citation(s) in RCA: 106] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 08/12/2019] [Accepted: 09/30/2019] [Indexed: 12/31/2022]
Abstract
How neural circuits develop in the human brain has remained almost impossible to study at the neuronal level. Here, we investigate human cortical neuron development, plasticity, and function using a mouse/human chimera model in which xenotransplanted human cortical pyramidal neurons integrate as single cells into the mouse cortex. Combined neuronal tracing, electrophysiology, and in vivo structural and functional imaging of the transplanted cells reveal a coordinated developmental roadmap recapitulating key milestones of human cortical neuron development. The human neurons display a prolonged developmental timeline, indicating the neuron-intrinsic retention of juvenile properties as an important component of human brain neoteny. Following maturation, human neurons in the visual cortex display tuned, decorrelated responses to visual stimuli, like mouse neurons, demonstrating their capacity for physiological synaptic integration in host cortical circuits. These findings provide new insights into human neuronal development and open novel avenues for the study of human neuronal function and disease. Video Abstract
Cell-intrinsic mechanisms of human neoteny in mouse-human chimeric cerebral cortex Human neurons show prolonged maturation and single-cell integration in mouse cortex Stable dendritic spines and long-term synaptic plasticity in xenotransplanted neurons Human neurons show decorrelated activity and tuned responses to visual stimuli
Collapse
Affiliation(s)
- Daniele Linaro
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium; Institut de Recherches en Biologie Humaine et Moléculaire (IRIBHM) and ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium
| | - Ben Vermaercke
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium; Neuro-Electronics Research Flanders, Kapeldreef 75, 3001 Leuven, Belgium
| | - Ryohei Iwata
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium; Institut de Recherches en Biologie Humaine et Moléculaire (IRIBHM) and ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium
| | - Arjun Ramaswamy
- Department of Neurosciences and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium; Neuro-Electronics Research Flanders, Kapeldreef 75, 3001 Leuven, Belgium; imec, 3001 Leuven, Belgium
| | - Baptiste Libé-Philippot
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium; Institut de Recherches en Biologie Humaine et Moléculaire (IRIBHM) and ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium
| | - Leila Boubakar
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium; Institut de Recherches en Biologie Humaine et Moléculaire (IRIBHM) and ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium
| | - Brittany A Davis
- Institut de Recherches en Biologie Humaine et Moléculaire (IRIBHM) and ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium
| | - Keimpe Wierda
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium
| | - Kristofer Davie
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium
| | | | | | - Angéline Bilheu
- Institut de Recherches en Biologie Humaine et Moléculaire (IRIBHM) and ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium
| | - Lore De Bruyne
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium
| | - David Gall
- Institut de Recherches en Biologie Humaine et Moléculaire (IRIBHM) and ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; Laboratoire de Physiologie et Pharmacologie and ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium
| | - Karl-Klaus Conzelmann
- Max von Pettenkofer-Institute and Gene Center, Ludwig-Maximilians-Universität Munchen, 81377 Munich, Germany
| | - Vincent Bonin
- Neuro-Electronics Research Flanders, Kapeldreef 75, 3001 Leuven, Belgium; imec, 3001 Leuven, Belgium; Department of Biology and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium; VIB, 3000 Leuven, Belgium.
| | - Pierre Vanderhaeghen
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium; Institut de Recherches en Biologie Humaine et Moléculaire (IRIBHM) and ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; VIB, 3000 Leuven, Belgium; Welbio, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium.
| |
Collapse
|
165
|
Association between autophagy and rapid eye movement sleep loss-associated neurodegenerative and patho-physio-behavioral changes. Sleep Med 2019; 63:29-37. [DOI: 10.1016/j.sleep.2019.04.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 03/26/2019] [Accepted: 04/24/2019] [Indexed: 12/13/2022]
|
166
|
Motta A, Berning M, Boergens KM, Staffler B, Beining M, Loomba S, Hennig P, Wissler H, Helmstaedter M. Dense connectomic reconstruction in layer 4 of the somatosensory cortex. Science 2019; 366:science.aay3134. [PMID: 31649140 DOI: 10.1126/science.aay3134] [Citation(s) in RCA: 137] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 10/11/2019] [Indexed: 12/11/2022]
Abstract
The dense circuit structure of mammalian cerebral cortex is still unknown. With developments in three-dimensional electron microscopy, the imaging of sizable volumes of neuropil has become possible, but dense reconstruction of connectomes is the limiting step. We reconstructed a volume of ~500,000 cubic micrometers from layer 4 of mouse barrel cortex, ~300 times larger than previous dense reconstructions from the mammalian cerebral cortex. The connectomic data allowed the extraction of inhibitory and excitatory neuron subtypes that were not predictable from geometric information. We quantified connectomic imprints consistent with Hebbian synaptic weight adaptation, which yielded upper bounds for the fraction of the circuit consistent with saturated long-term potentiation. These data establish an approach for the locally dense connectomic phenotyping of neuronal circuitry in the mammalian cortex.
Collapse
Affiliation(s)
- Alessandro Motta
- Department of Connectomics, Max Planck Institute for Brain Research, D-60438 Frankfurt, Germany
| | - Manuel Berning
- Department of Connectomics, Max Planck Institute for Brain Research, D-60438 Frankfurt, Germany
| | - Kevin M Boergens
- Department of Connectomics, Max Planck Institute for Brain Research, D-60438 Frankfurt, Germany
| | - Benedikt Staffler
- Department of Connectomics, Max Planck Institute for Brain Research, D-60438 Frankfurt, Germany
| | - Marcel Beining
- Department of Connectomics, Max Planck Institute for Brain Research, D-60438 Frankfurt, Germany
| | - Sahil Loomba
- Department of Connectomics, Max Planck Institute for Brain Research, D-60438 Frankfurt, Germany
| | - Philipp Hennig
- Probabilistic Numerics Group, Max Planck Institute for Intelligent Systems, D-72076 Tübingen, Germany
| | - Heiko Wissler
- Department of Connectomics, Max Planck Institute for Brain Research, D-60438 Frankfurt, Germany
| | - Moritz Helmstaedter
- Department of Connectomics, Max Planck Institute for Brain Research, D-60438 Frankfurt, Germany.
| |
Collapse
|
167
|
Schubert R, Herzog S, Trenholm S, Roska B, Müller DJ. Magnetically guided virus stamping for the targeted infection of single cells or groups of cells. Nat Protoc 2019; 14:3205-3219. [DOI: 10.1038/s41596-019-0221-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 07/02/2019] [Indexed: 01/10/2023]
|
168
|
Experience-dependent structural plasticity at pre- and postsynaptic sites of layer 2/3 cells in developing visual cortex. Proc Natl Acad Sci U S A 2019; 116:21812-21820. [PMID: 31591211 DOI: 10.1073/pnas.1914661116] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The developing brain can respond quickly to altered sensory experience by circuit reorganization. During a critical period in early life, neurons in the primary visual cortex rapidly lose responsiveness to an occluded eye and come to respond better to the open eye. While physiological and some of the molecular mechanisms of this process have been characterized, its structural basis, except for the well-known changes in the thalamocortical projection, remains obscure. To elucidate the relationship between synaptic remodeling and functional changes during this experience-dependent process, we used 2-photon microscopy to image synaptic structures of sparsely labeled layer 2/3 neurons in the binocular zone of mouse primary visual cortex. Anatomical changes at presynaptic and postsynaptic sites in mice undergoing monocular visual deprivation (MD) were compared to those in control mice with normal visual experience. We found that postsynaptic spines remodeled quickly in response to MD, with neurons more strongly dominated by the deprived eye losing more spines. These postsynaptic changes parallel changes in visual responses during MD and their recovery after restoration of binocular vision. In control animals with normal visual experience, the formation of presynaptic boutons increased during the critical period and then declined. MD affected bouton formation, but with a delay, blocking it after 3 d. These findings reveal intracortical anatomical changes in cellular layers of the cortex that can account for rapid activity-dependent plasticity.
Collapse
|
169
|
N-terminal alternative splicing of GluN1 regulates the maturation of excitatory synapses and seizure susceptibility. Proc Natl Acad Sci U S A 2019; 116:21207-21212. [PMID: 31570583 DOI: 10.1073/pnas.1905721116] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The majority of NMDA receptors (NMDARs) in the brain are composed of 2 GluN1 and 2 GluN2 subunits. The inclusion or exclusion of 1 N-terminal and 2 C-terminal domains of GluN1 results in 8 splicing variants that exhibit distinct temporal and spatial patterns of expression and functional properties. However, previous functional analyses of Grin1 variants have been done using heterologous expression and the in vivo function of Grin1 splicing is unknown. Here we show that N-terminal splicing of GluN1 has important functions in the maturation of excitatory synapses. The inclusion of exon 5 of Grin1 is up-regulated in several brain regions such as the thalamus and neocortex. We find that deletion of Grin1 exon 5 disrupts the developmental remodeling of NMDARs in thalamic neurons and the effect is distinct from that of Grin2a (GluN2A) deletion. Deletion of Grin2a or exon 5 of Grin1 alone partially attenuates the shortening of NMDAR-mediated excitatory postsynaptic currents (NMDAR-EPSCs) during early life, whereas deletion of both Grin2a and exon 5 of Grin1 completely abolishes the developmental change in NMDAR-EPSC decay time. Deletion of exon 5 of Grin1 leads to an overproduction of excitatory synapses in layer 5 pyramidal neurons in the cortex and increases seizure susceptibility in adult mice. Our findings demonstrate that N-terminal splicing of GluN1 has important functions in synaptic maturation and neuronal network excitability.
Collapse
|
170
|
Nishiyama J. Plasticity of dendritic spines: Molecular function and dysfunction in neurodevelopmental disorders. Psychiatry Clin Neurosci 2019; 73:541-550. [PMID: 31215705 DOI: 10.1111/pcn.12899] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 06/04/2019] [Accepted: 06/06/2019] [Indexed: 02/06/2023]
Abstract
Dendritic spines are tiny postsynaptic protrusions from a dendrite that receive most of the excitatory synaptic input in the brain. Functional and structural changes in dendritic spines are critical for synaptic plasticity, a cellular model of learning and memory. Conversely, altered spine morphology and plasticity are common hallmarks of human neurodevelopmental disorders, such as intellectual disability and autism. The advances in molecular and optical techniques have allowed for exploration of dynamic changes in structure and signal transduction at single-spine resolution, providing significant insights into the molecular regulation underlying spine structural plasticity. Here, I review recent findings on: how synaptic stimulation leads to diverse forms of spine structural plasticity; how the associated biochemical signals are initiated and transmitted into neuronal compartments; and how disruption of single genes associated with neurodevelopmental disorders can lead to abnormal spine structure in human and mouse brains. In particular, I discuss the functions of the Ras superfamily of small GTPases in spatiotemporal regulation of the actin cytoskeleton and protein synthesis in dendritic spines. Multiple lines of evidence implicate disrupted Ras signaling pathways in the spine structural abnormalities observed in neurodevelopmental disorders. Both deficient and excessive Ras activities lead to disrupted spine structure and deficits in learning and memory. Dysregulation of spine Ras signaling, therefore, may play a key role in the pathogenesis of multiple neurodevelopmental disorders with distinct etiologies.
Collapse
Affiliation(s)
- Jun Nishiyama
- Program in Neuroscience and Behavioral Disorders, Duke-National University of Singapore Medical School, Singapore
| |
Collapse
|
171
|
Saadipour K, Tiberi A, Lombardo S, Grajales E, Montroull L, Mañucat-Tan NB, LaFrancois J, Cammer M, Mathews PM, Scharfman HE, Liao FF, Friedman WJ, Zhou XF, Tesco G, Chao MV. Regulation of BACE1 expression after injury is linked to the p75 neurotrophin receptor. Mol Cell Neurosci 2019; 99:103395. [PMID: 31422108 DOI: 10.1016/j.mcn.2019.103395] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/24/2019] [Accepted: 08/08/2019] [Indexed: 12/25/2022] Open
Abstract
BACE1 is a transmembrane aspartic protease that cleaves various substrates and it is required for normal brain function. BACE1 expression is high during early development, but it is reduced in adulthood. Under conditions of stress and injury, BACE1 levels are increased; however, the underlying mechanisms that drive BACE1 elevation are not well understood. One mechanism associated with brain injury is the activation of injurious p75 neurotrophin receptor (p75), which can trigger pathological signals. Here we report that within 72 h after controlled cortical impact (CCI) or laser injury, BACE1 and p75 are increased and tightly co-expressed in cortical neurons of mouse brain. Additionally, BACE1 is not up-regulated in p75 null mice in response to focal cortical injury, while p75 over-expression results in BACE1 augmentation in HEK-293 and SY5Y cell lines. A luciferase assay conducted in SY5Y cell line revealed that BACE1 expression is regulated at the transcriptional level in response to p75 transfection. Interestingly, this effect does not appear to be dependent upon p75 ligands including mature and pro-neurotrophins. In addition, BACE1 activity on amyloid precursor protein (APP) is enhanced in SY5Y-APP cells transfected with a p75 construct. Lastly, we found that the activation of c-jun n-terminal kinase (JNK) by p75 contributes to BACE1 up-regulation. This study explores how two injury-induced molecules are intimately connected and suggests a potential link between p75 signaling and the expression of BACE1 after brain injury.
Collapse
Affiliation(s)
- Khalil Saadipour
- Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016, USA.
| | - Alexia Tiberi
- Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016, USA; Bio@SNS Laboratory, Scuola Normale Superiore, Piazza dei Cavalieri 7, Pisa, 56126, Italy
| | - Sylvia Lombardo
- Alzheimer's Disease Research Laboratory, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA, 02111, USA
| | - Elena Grajales
- Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016, USA
| | - Laura Montroull
- Department of Biological Sciences, Rutgers Life Sciences Center, Rutgers University, Newark, NJ 07102, USA
| | - Noralyn B Mañucat-Tan
- School of Pharmacy and Medical Sciences, Sansom Institute, University of South Australia, Adelaide, South Australia, 5000, Australia
| | - John LaFrancois
- The Nathan Kline Institute of Psychiatric Research, Center for Dementia Research, Orangeburg, NY 10962, USA
| | - Michael Cammer
- DART Microscopy Laboratory, NYU Langone Medical Center, New York, NY 10016, USA
| | - Paul M Mathews
- The Nathan Kline Institute of Psychiatric Research, Center for Dementia Research, Orangeburg, NY 10962, USA
| | - Helen E Scharfman
- The Nathan Kline Institute of Psychiatric Research, Center for Dementia Research, Orangeburg, NY 10962, USA
| | - Francesca-Fang Liao
- Department of Pharmacology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
| | - Wilma J Friedman
- Department of Biological Sciences, Rutgers Life Sciences Center, Rutgers University, Newark, NJ 07102, USA
| | - Xin-Fu Zhou
- School of Pharmacy and Medical Sciences, Sansom Institute, University of South Australia, Adelaide, South Australia, 5000, Australia
| | - Giueseppina Tesco
- Alzheimer's Disease Research Laboratory, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA, 02111, USA
| | - Moses V Chao
- Departments of Cell Biology, Physiology & Neuroscience, and Psychiatry, Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, New York 10016, USA.
| |
Collapse
|
172
|
Xu ZX, Tan JW, Xu H, Hill CJ, Ostrovskaya O, Martemyanov KA, Xu B. Caspase-2 promotes AMPA receptor internalization and cognitive flexibility via mTORC2-AKT-GSK3β signaling. Nat Commun 2019; 10:3622. [PMID: 31399584 PMCID: PMC6689033 DOI: 10.1038/s41467-019-11575-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 07/23/2019] [Indexed: 01/22/2023] Open
Abstract
Caspase-2 is the most evolutionarily conserved member in the caspase family of proteases and is constitutively expressed in most cell types including neurons; however, its physiological function remains largely unknown. Here we report that caspase-2 plays a critical role in synaptic plasticity and cognitive flexibility. We found that caspase-2 deficiency led to deficits in dendritic spine pruning, internalization of AMPA receptors and long-term depression. Our results indicate that caspase-2 degrades Rictor, a key mTOR complex 2 (mTORC2) component, to inhibit Akt activation, which leads to enhancement of the GSK3β activity and thereby long-term depression. Furthermore, we found that mice lacking caspase-2 displayed elevated levels of anxiety, impairment in reversal water maze learning, and little memory loss over time. These results not only uncover a caspase-2-mTORC2-Akt-GSK3β signaling pathway, but also suggest that caspase-2 is important for memory erasing and normal behaviors by regulating synaptic number and transmission.
Collapse
Affiliation(s)
- Zhi-Xiang Xu
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL, 33458, USA
| | - Ji-Wei Tan
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL, 33458, USA
| | - Haifei Xu
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL, 33458, USA
| | - Cassandra J Hill
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL, 33458, USA
| | - Olga Ostrovskaya
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL, 33458, USA
| | - Kirill A Martemyanov
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL, 33458, USA
| | - Baoji Xu
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL, 33458, USA.
| |
Collapse
|
173
|
Abstract
Myelination is an important process that takes place also in the periphery during development and in the adulthood. Myelin serves as an electric isolator for axons, leading to a fast conduction of the action potential, and provides trophic support for the axon, both aspects highly important for the proper function of the nervous system. In the central nervous system, myelination starts shortly after birth and cells from the oligodendrocyte lineage tightly regulate this process during the whole life span. Initially, it was thought that under physiological conditions myelin generation only occurs in early postnatal development and that myelination stops at early adult ages. Historically, the process of myelination has mainly been studied in fixed tissue, and predominantly analyzed by electron microscopy, bringing valuable insights in the structure and distribution of myelin in the central nervous system. Nevertheless, the outdated notion of the static nature of myelin during adulthood was challenged in the past decades by the development of new techniques bringing in a new picture of a lively structure that is in constant remodeling under physiological and disease conditions. As fixed tissue can only provide information at a specific timepoint, the necessity of new techniques to study this process in vivo has become clear. In this chapter, we will review some of the latest techniques developed in order to study myelin and the oligodendrocyte lineage, as these cells are important for the formation and restructuration of the myelin. We will also introduce a protocol to prepare a cranial window to study NG2-glia (also known as oligodendrocyte progenitor cells) of the cerebral cortex in vivo, by 2-photon laser scanning microscopy. However, this technique can also be performed to study other cell populations or structures such as myelin, which will be discussed in this chapter as well. Despite being simple, this protocol has shown to be powerful to study the oligodendrocyte lineage and potentially is applicable to study myelin in vivo, which could turn into a key technique in the understanding of myelination and other functions that the oligodendrocyte lineage might have under physiological and disease conditions.
Collapse
|
174
|
Cano-Velázquez MS, Davoodzadeh N, Halaney D, Jonak CR, Binder DK, Hernández-Cordero J, Aguilar G. Enhanced near infrared optical access to the brain with a transparent cranial implant and scalp optical clearing. BIOMEDICAL OPTICS EXPRESS 2019; 10:3369-3379. [PMID: 31467783 PMCID: PMC6706046 DOI: 10.1364/boe.10.003369] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 05/12/2019] [Accepted: 05/29/2019] [Indexed: 06/10/2023]
Abstract
We report on the enhanced optical transmittance in the NIR wavelength range (900 to 2400 nm) offered by a transparent Yttria-stabilized zirconia (YSZ) implant coupled with optical clearing agents (OCAs). The enhancement in optical access to the brain is evaluated upon comparing ex-vivo transmittance measurements of mice native skull and the YSZ cranial implant with scalp and OCAs. An increase in transmittance of up to 50% and attenuation lengths of up to 2.4 mm (i.e., a five-fold increase in light penetration) are obtained with the YSZ implant and the OCAs. The use of this ceramic implant and the biocompatible optical clearing agents offer attractive features for NIR optical techniques for brain theranostics.
Collapse
Affiliation(s)
| | - Nami Davoodzadeh
- Department of Mechanical Engineering, University of California, Riverside, CA,
USA
| | - David Halaney
- Department of Mechanical Engineering, University of California, Riverside, CA,
USA
| | - Carrie R. Jonak
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, CA,
USA
| | - Devin K. Binder
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, CA,
USA
| | - Juan Hernández-Cordero
- Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, México
| | - Guillermo Aguilar
- Department of Mechanical Engineering, University of California, Riverside, CA,
USA
| |
Collapse
|
175
|
Quinn DP, Kolar A, Harris SA, Wigerius M, Fawcett JP, Krueger SR. The Stability of Glutamatergic Synapses Is Independent of Activity Level, but Predicted by Synapse Size. Front Cell Neurosci 2019; 13:291. [PMID: 31316356 PMCID: PMC6609312 DOI: 10.3389/fncel.2019.00291] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 06/14/2019] [Indexed: 01/23/2023] Open
Abstract
Neuronal activity is thought to drive the remodeling of circuits in the mammalian cerebral cortex. However, its precise function in the underlying formation and elimination of glutamatergic synapses has remained controversial. To clarify the role of activity in synapse turnover, we have assessed the effects of inhibition of glutamate release from a sparse subset of cultured hippocampal neurons on synapse turnover. Sustained chemogenetic attenuation of release through presynaptic expression of a designer receptor exclusively activated by designer drugs (DREADD) had no effect on the formation or elimination of glutamatergic synapses. Sparse expression of tetanus neurotoxin light chain (TeNT-LC), a synaptobrevin-cleaving protease that completely abolishes neurotransmitter release, likewise did not lead to changes in the rate of synapse elimination, although it reduced the rate of synapse formation. The stability of active and silenced synapses correlated with measures of synapse size. While not excluding a modulatory role in synapse elimination, our findings show that synaptic activity is neither required for the removal nor the maintenance of glutamatergic synapses between hippocampal neurons. Our results also demonstrate that the stability of glutamatergic synapses scales with their size irrespective of their activity.
Collapse
Affiliation(s)
- Dylan P Quinn
- Department of Physiology and Biophysics, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada.,Department of Pharmacology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Annette Kolar
- Department of Physiology and Biophysics, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Sydney A Harris
- Department of Physiology and Biophysics, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Michael Wigerius
- Department of Pharmacology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - James P Fawcett
- Department of Pharmacology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Stefan R Krueger
- Department of Physiology and Biophysics, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| |
Collapse
|
176
|
Deger M, Seeholzer A, Gerstner W. Multicontact Co-operativity in Spike-Timing-Dependent Structural Plasticity Stabilizes Networks. Cereb Cortex 2019; 28:1396-1415. [PMID: 29300903 PMCID: PMC6041941 DOI: 10.1093/cercor/bhx339] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 11/30/2017] [Indexed: 12/12/2022] Open
Abstract
Excitatory synaptic connections in the adult neocortex consist of multiple synaptic contacts, almost exclusively formed on dendritic spines. Changes of spine volume, a correlate of synaptic strength, can be tracked in vivo for weeks. Here, we present a combined model of structural and spike-timing–dependent plasticity that explains the multicontact configuration of synapses in adult neocortical networks under steady-state and lesion-induced conditions. Our plasticity rule with Hebbian and anti-Hebbian terms stabilizes both the postsynaptic firing rate and correlations between the pre- and postsynaptic activity at an active synaptic contact. Contacts appear spontaneously at a low rate and disappear if their strength approaches zero. Many presynaptic neurons compete to make strong synaptic connections onto a postsynaptic neuron, whereas the synaptic contacts of a given presynaptic neuron co-operate via postsynaptic firing. We find that co-operation of multiple synaptic contacts is crucial for stable, long-term synaptic memories. In simulations of a simplified network model of barrel cortex, our plasticity rule reproduces whisker-trimming–induced rewiring of thalamocortical and recurrent synaptic connectivity on realistic time scales.
Collapse
Affiliation(s)
- Moritz Deger
- School of Computer and Communication Sciences and School of Life Sciences, Brain Mind Institute, École Polytechnique Fédérale de Lausanne, 1015 Lausanne EPFL, Switzerland.,Institute for Zoology, Faculty of Mathematics and Natural Sciences, University of Cologne, 50674 Cologne, Germany
| | - Alexander Seeholzer
- School of Computer and Communication Sciences and School of Life Sciences, Brain Mind Institute, École Polytechnique Fédérale de Lausanne, 1015 Lausanne EPFL, Switzerland
| | - Wulfram Gerstner
- School of Computer and Communication Sciences and School of Life Sciences, Brain Mind Institute, École Polytechnique Fédérale de Lausanne, 1015 Lausanne EPFL, Switzerland
| |
Collapse
|
177
|
Hill SA, Blaeser AS, Coley AA, Xie Y, Shepard KA, Harwell CC, Gao WJ, Garcia ADR. Sonic hedgehog signaling in astrocytes mediates cell type-specific synaptic organization. eLife 2019; 8:45545. [PMID: 31194676 PMCID: PMC6629371 DOI: 10.7554/elife.45545] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 06/13/2019] [Indexed: 01/08/2023] Open
Abstract
Astrocytes have emerged as integral partners with neurons in regulating synapse formation and function, but the mechanisms that mediate these interactions are not well understood. Here, we show that Sonic hedgehog (Shh) signaling in mature astrocytes is required for establishing structural organization and remodeling of cortical synapses in a cell type-specific manner. In the postnatal cortex, Shh signaling is active in a subpopulation of mature astrocytes localized primarily in deep cortical layers. Selective disruption of Shh signaling in astrocytes produces a dramatic increase in synapse number specifically on layer V apical dendrites that emerges during adolescence and persists into adulthood. Dynamic turnover of dendritic spines is impaired in mutant mice and is accompanied by an increase in neuronal excitability and a reduction of the glial-specific, inward-rectifying K+ channel Kir4.1. These data identify a critical role for Shh signaling in astrocyte-mediated modulation of neuronal activity required for sculpting synapses. A central system of neurons in the spinal cord and brain coordinate most of our body’s actions, ranging from regulating our heart rate to controlling our movement and thoughts. As the brain develops, neurons form specialized contacts with one another known as synapses. If the number of synapses is not properly regulated this can disrupt communication between the neurons, leading to diseases like schizophrenia and autism. As the brain develops, it first forms an excess of synapses and later eliminates unnecessary or weak connections. Various factors, such gene expression or a neuron’s level of activity, regulate this turnover process. However, neurons cannot do this alone, and rely on other types of cells to help regulate their behavior. In the central nervous system, for example, a cell called an astrocyte is known to support the formation and activity of synapses. Now, Hill and Blaeser et al. show that astrocytes also exert influence over synaptic turnover during development, leading to long lasting changes in the number of synapses. Hill, Blaeser et al. revealed that disrupting activity of the signaling pathway known as Sonic hedgehog, or Shh for short, in the astrocytes of mice led to disordered synaptic connections. Notably, neurons produce Shh, suggesting that neurons use this signaling pathway to communicate to specific astrocyte partners. Further experiments showed that reducing astrocyte’s ability to respond to Shh impaired synaptic turnover as the brain developed, leading to an overabundance of synapses. Importantly, these effects were only found to influence neuron populations associated with astrocytes that actively use Shh signaling. This suggests that distinct populations of neurons and astrocytes interact in specialized ways to build the connections within the nervous system. To address how astrocytes use Shh signaling to regulate synaptic turnover, Hill, Blaeser et al. examined gene expression changes in astrocytes that lack Shh signaling. Astrocytes with a reduced capacity to respond to Shh were found to have lower levels of a protein responsible for transporting potassium ions into and out of the cell. This impairs astrocyte’s ability to regulate neuronal activity, which may lead to a failure in eliminating unnecessary synapses. Understanding how synapses are controlled and organized by astrocytes could help identify new ways to treat diseases of the developing nervous system. However, further studies would be needed to improve our understanding of how this process works.
Collapse
Affiliation(s)
- Steven A Hill
- Department of Biology, Drexel University, Philadelphia, United States
| | - Andrew S Blaeser
- Department of Biology, Drexel University, Philadelphia, United States
| | - Austin A Coley
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, United States
| | - Yajun Xie
- Department of Neurobiology, Harvard Medical School, Boston, United States
| | | | - Corey C Harwell
- Department of Neurobiology, Harvard Medical School, Boston, United States
| | - Wen-Jun Gao
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, United States
| | - A Denise R Garcia
- Department of Biology, Drexel University, Philadelphia, United States.,Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, United States
| |
Collapse
|
178
|
Chidambaram SB, Rathipriya AG, Bolla SR, Bhat A, Ray B, Mahalakshmi AM, Manivasagam T, Thenmozhi AJ, Essa MM, Guillemin GJ, Chandra R, Sakharkar MK. Dendritic spines: Revisiting the physiological role. Prog Neuropsychopharmacol Biol Psychiatry 2019; 92:161-193. [PMID: 30654089 DOI: 10.1016/j.pnpbp.2019.01.005] [Citation(s) in RCA: 150] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 01/04/2019] [Accepted: 01/12/2019] [Indexed: 12/11/2022]
Abstract
Dendritic spines are small, thin, specialized protrusions from neuronal dendrites, primarily localized in the excitatory synapses. Sophisticated imaging techniques revealed that dendritic spines are complex structures consisting of a dense network of cytoskeletal, transmembrane and scaffolding molecules, and numerous surface receptors. Molecular signaling pathways, mainly Rho and Ras family small GTPases pathways that converge on actin cytoskeleton, regulate the spine morphology and dynamics bi-directionally during synaptic activity. During synaptic plasticity the number and shapes of dendritic spines undergo radical reorganizations. Long-term potentiation (LTP) induction promote spine head enlargement and the formation and stabilization of new spines. Long-term depression (LTD) results in their shrinkage and retraction. Reports indicate increased spine density in the pyramidal neurons of autism and Fragile X syndrome patients and reduced density in the temporal gyrus loci of schizophrenic patients. Post-mortem reports of Alzheimer's brains showed reduced spine number in the hippocampus and cortex. This review highlights the spine morphogenesis process, the activity-dependent structural plasticity and mechanisms by which synaptic activity sculpts the dendritic spines, the structural and functional changes in spines during learning and memory using LTP and LTD processes. It also discusses on spine status in neurodegenerative diseases and the impact of nootropics and neuroprotective agents on the functional restoration of dendritic spines.
Collapse
Affiliation(s)
- Saravana Babu Chidambaram
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India.
| | - A G Rathipriya
- Food and Brain Research Foundation, Chennai, Tamil Nadu, India
| | - Srinivasa Rao Bolla
- Department of Anatomy, College of Medicine, Imam Abdulrahman Bin Faisal University, Damam, Saudi Arabia
| | - Abid Bhat
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India
| | - Bipul Ray
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India
| | - Arehally Marappa Mahalakshmi
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India
| | - Thamilarasan Manivasagam
- Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalainagar, Tamilnadu, India
| | - Arokiasamy Justin Thenmozhi
- Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalainagar, Tamilnadu, India
| | - Musthafa Mohamed Essa
- Department of Food Science and Nutrition, CAMS, Sultan Qaboos University, Muscat, Oman
| | - Gilles J Guillemin
- Neuropharmacology Group, Faculty of Medicine and Health Sciences, Deb Bailey MND Research Laboratory, Macquarie University, Sydney, NSW 2109, Australia
| | - Ramesh Chandra
- Department of Chemistry, Ambedkar Centre for BioMedical Research, Delhi University, Delhi 110007, India
| | - Meena Kishore Sakharkar
- College of Pharmacy and Nutrition, University of Saskatchewan, 107, Wiggins Road, Saskatoon, SK S7N 5C9, Canada.
| |
Collapse
|
179
|
Pannexin 1 Regulates Network Ensembles and Dendritic Spine Development in Cortical Neurons. eNeuro 2019; 6:ENEURO.0503-18.2019. [PMID: 31118206 PMCID: PMC6557035 DOI: 10.1523/eneuro.0503-18.2019] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 05/13/2019] [Accepted: 05/14/2019] [Indexed: 01/22/2023] Open
Abstract
Dendritic spines are the postsynaptic targets of excitatory synaptic inputs that undergo extensive proliferation and maturation during the first postnatal month in mice. However, our understanding of the molecular mechanisms that regulate spines during this critical period is limited. Previous work has shown that pannexin 1 (Panx1) regulates neurite growth and synaptic plasticity. We therefore investigated the impact of global Panx1 KO on spontaneous cortical neuron activity using Ca2+ imaging and in silico network analysis. Panx1 KO increased both the number and size of spontaneous co-active cortical neuron network ensembles. To understand the basis for these findings, we investigated Panx1 expression in postnatal synaptosome preparations from early postnatal mouse cortex. Between 2 and 4 postnatal weeks, we observed a precipitous drop in cortical synaptosome protein levels of Panx1, suggesting it regulates synapse proliferation and/or maturation. At the same time points, we observed significant enrichment of the excitatory postsynaptic density proteins PSD-95, GluA1, and GluN2a in cortical synaptosomes from global Panx1 knock-out mice. Ex vivo analysis of pyramidal neuron structure in somatosensory cortex revealed a consistent increase in dendritic spine densities in both male and female Panx1 KO mice. Similar findings were observed in an excitatory neuron-specific Panx1 KO line (Emx1-Cre driven; Panx1 cKOE) and in primary Panx1 KO cortical neurons cultured in vitro. Altogether, our study suggests that Panx1 negatively regulates cortical dendritic spine development.
Collapse
|
180
|
Ikegami A, Haruwaka K, Wake H. Microglia: Lifelong modulator of neural circuits. Neuropathology 2019; 39:173-180. [DOI: 10.1111/neup.12560] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 04/15/2019] [Accepted: 04/15/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Ako Ikegami
- Division of System Neuroscience; Kobe University Graduate School of Medicine; Kobe Japan
| | - Koichiro Haruwaka
- Division of System Neuroscience; Kobe University Graduate School of Medicine; Kobe Japan
| | - Hiroaki Wake
- Division of System Neuroscience; Kobe University Graduate School of Medicine; Kobe Japan
- Core Research for Evolutional Science and Technology; Japan Science and Technology Agency; Saitama Japan
| |
Collapse
|
181
|
Vellema M, Diales Rocha M, Bascones S, Zsebők S, Dreier J, Leitner S, Van der Linden A, Brewer J, Gahr M. Accelerated redevelopment of vocal skills is preceded by lasting reorganization of the song motor circuitry. eLife 2019; 8:43194. [PMID: 31099755 PMCID: PMC6570526 DOI: 10.7554/elife.43194] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 05/16/2019] [Indexed: 01/16/2023] Open
Abstract
Complex motor skills take considerable time and practice to learn. Without continued practice the level of skill performance quickly degrades, posing a problem for the timely utilization of skilled motor behaviors. Here we quantified the recurring development of vocal motor skills and the accompanying changes in synaptic connectivity in the brain of a songbird, while manipulating skill performance by consecutively administrating and withdrawing testosterone. We demonstrate that a songbird with prior singing experience can significantly accelerate the re-acquisition of vocal performance. We further demonstrate that an increase in vocal performance is accompanied by a pronounced synaptic pruning in the forebrain vocal motor area HVC, a reduction that is not reversed when birds stop singing. These results provide evidence that lasting synaptic changes in the motor circuitry are associated with the savings of motor skills, enabling a rapid recovery of motor performance under environmental time constraints.
Collapse
Affiliation(s)
- Michiel Vellema
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany.,Bio Imaging Lab, University of Antwerp, Antwerp, Belgium
| | - Mariana Diales Rocha
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany
| | - Sabrina Bascones
- Program for Inflammatory and Cardiovascular Disorders, Institut Hospital del Mar d'Investigacions Mèdiques, Barcelona, Spain
| | - Sándor Zsebők
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary
| | - Jes Dreier
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Stefan Leitner
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany
| | | | - Jonathan Brewer
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Manfred Gahr
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany
| |
Collapse
|
182
|
Corsetti S, Gunn-Moore F, Dholakia K. Light sheet fluorescence microscopy for neuroscience. J Neurosci Methods 2019; 319:16-27. [DOI: 10.1016/j.jneumeth.2018.07.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 06/03/2018] [Accepted: 07/16/2018] [Indexed: 12/29/2022]
|
183
|
Witkowski ED, Gao Y, Gavsyuk AF, Maor I, DeWalt GJ, Eldred WD, Mizrahi A, Davison IG. Rapid Changes in Synaptic Strength After Mild Traumatic Brain Injury. Front Cell Neurosci 2019; 13:166. [PMID: 31105533 PMCID: PMC6498971 DOI: 10.3389/fncel.2019.00166] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 04/08/2019] [Indexed: 12/12/2022] Open
Abstract
Traumatic brain injury (TBI) affects millions of Americans annually, but effective treatments remain inadequate due to our poor understanding of how injury impacts neural function. Data are particularly limited for mild, closed-skull TBI, which forms the majority of human cases, and for acute injury phases, when trauma effects and compensatory responses appear highly dynamic. Here we use a mouse model of mild TBI to characterize injury-induced synaptic dysfunction, and examine its progression over the hours to days after trauma. Mild injury consistently caused both locomotor deficits and localized neuroinflammation in piriform and entorhinal cortices, along with reduced olfactory discrimination ability. Using whole-cell recordings to characterize synaptic input onto piriform pyramidal neurons, we found moderate effects on excitatory or inhibitory synaptic function at 48 h after TBI and robust increase in excitatory inputs in slices prepared 1 h after injury. Excitatory increases predominated over inhibitory effects, suggesting that loss of excitatory-inhibitory balance is a common feature of both mild and severe TBI. Our data indicate that mild injury drives rapidly evolving alterations in neural function in the hours following injury, highlighting the need to better characterize the interplay between the primary trauma responses and compensatory effects during this early time period.
Collapse
Affiliation(s)
| | - Yuan Gao
- Department of Biology, Boston University, Boston, MA, United States
| | | | - Ido Maor
- Department of Neurobiology, Edmond & Lily Safra Center for Brain Sciences, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Gloria J. DeWalt
- Department of Biology, Boston University, Boston, MA, United States
| | | | - Adi Mizrahi
- Department of Neurobiology, Edmond & Lily Safra Center for Brain Sciences, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ian G. Davison
- Department of Biology, Boston University, Boston, MA, United States
| |
Collapse
|
184
|
Acker D, Paradis S, Miller P. Stable memory and computation in randomly rewiring neural networks. J Neurophysiol 2019; 122:66-80. [PMID: 30969897 DOI: 10.1152/jn.00534.2018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Our brains must maintain a representation of the world over a period of time much longer than the typical lifetime of the biological components producing that representation. For example, recent research suggests that dendritic spines in the adult mouse hippocampus are transient with an average lifetime of ~10 days. If this is true, and if turnover is equally likely for all spines, ~95% of excitatory synapses onto a particular neuron will turn over within 30 days; however, a neuron's receptive field can be relatively stable over this period. Here, we use computational modeling to ask how memories can persist in neural circuits such as the hippocampus and visual cortex in the face of synapse turnover. We demonstrate that Hebbian plasticity during replay of presynaptic activity patterns can integrate newly formed synapses into pre-existing memories. Furthermore, we find that Hebbian plasticity during replay is sufficient to stabilize the receptive fields of hippocampal place cells in a model of the grid-cell-to-place-cell transformation in CA1 and of orientation-selective cells in a model of the center-surround-to-simple-cell transformation in V1. Together, these data suggest that a simple plasticity rule, correlative Hebbian plasticity of synaptic strengths, is sufficient to preserve neural representations in the face of synapse turnover, even in the absence of activity-dependent structural plasticity. NEW & NOTEWORTHY Recent research suggests that synapses turn over rapidly in some brain structures; however, memories seem to persist for much longer. We show that Hebbian plasticity of synaptic strengths during reactivation events can preserve memory in computational models of hippocampal and cortical networks despite turnover of all synapses. Our results suggest that memory can be stored in the correlation structure of a network undergoing rapid synaptic remodeling.
Collapse
Affiliation(s)
- Daniel Acker
- Volen National Center for Complex Systems, Brandeis University , Waltham, Massachusetts.,Department of Biology, Brandeis University , Waltham, Massachusetts
| | - Suzanne Paradis
- Volen National Center for Complex Systems, Brandeis University , Waltham, Massachusetts.,Department of Biology, Brandeis University , Waltham, Massachusetts
| | - Paul Miller
- Volen National Center for Complex Systems, Brandeis University , Waltham, Massachusetts.,Department of Biology, Brandeis University , Waltham, Massachusetts
| |
Collapse
|
185
|
De Niz M, Nacer A, Frischknecht F. Intravital microscopy: Imaging host-parasite interactions in the brain. Cell Microbiol 2019; 21:e13024. [PMID: 30830993 DOI: 10.1111/cmi.13024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 02/14/2019] [Accepted: 02/24/2019] [Indexed: 12/31/2022]
Abstract
Intravital fluorescence microscopy (IVM) is a powerful technique for imaging multiple organs, including the brain of living mice and rats. It enables the direct visualisation of cells in situ providing a real-life view of biological processes that in vitro systems cannot. In addition, to the technological advances in microscopy over the last decade, there have been supporting innovations in data storage and analytical packages that enable the visualisation and analysis of large data sets. Here, we review the advantages and limitations of techniques predominantly used for brain IVM, including thinned skull windows, open skull cortical windows, and a miniaturised optical system based on microendoscopic probes that can be inserted into deep tissues. Further, we explore the relevance of these techniques for the field of parasitology. Several protozoan infections are associated with neurological symptoms including Plasmodium spp., Toxoplasma spp., and Trypanosoma spp. IVM has led to crucial findings on these parasite species, which are discussed in detail in this review.
Collapse
Affiliation(s)
- Mariana De Niz
- Institute of Cell Biology, University of Bern, Bern, Switzerland.,Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasglow, UK
| | - Adéla Nacer
- Division of Bacteriology, National Institute for Biological Standards and Control, Medicines and Healthcare products Regulatory Agency, EN63QG, Potters Bar, UK
| | - Friedrich Frischknecht
- Parasitology-Centre for Infectious Diseases, University of Heidelberg Medical School, Heidelberg, Germany
| |
Collapse
|
186
|
General anesthetic exposure in adolescent rats causes persistent maladaptations in cognitive and affective behaviors and neuroplasticity. Neuropharmacology 2019; 150:153-163. [PMID: 30926450 DOI: 10.1016/j.neuropharm.2019.03.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 03/15/2019] [Accepted: 03/15/2019] [Indexed: 01/25/2023]
Abstract
Accumulating evidence indicates that exposure to general anesthetics during infancy and childhood can cause persistent cognitive impairment, alterations in synaptic plasticity, and, to a lesser extent, increased incidence of behavioral disorders. Unfortunately, the developmental parameters of susceptibility to general anesthetics are not well understood. Adolescence is a critical developmental period wherein multiple late developing brain regions may also be vulnerable to enduring general anesthetic effects. Given the breadth of the adolescent age span, this group potentially represents millions more individuals than those exposed during early childhood. In this study, isoflurane exposure within a well-characterized adolescent period in Sprague-Dawley rats elicited immediate and persistent anxiety- and impulsive-like responding, as well as delayed cognitive impairment into adulthood. These behavioral abnormalities were paralleled by atypical dendritic spine morphology in the prefrontal cortex (PFC) and hippocampus (HPC), suggesting delayed anatomical maturation, and shifts in inhibitory function that suggest hypermaturation of extrasynaptic GABAA receptor inhibition. Preventing this hypermaturation of extrasynaptic GABAA receptor-mediated function in the PFC selectively reversed enhanced impulsivity resulting from adolescent isoflurane exposure. Taken together, these data demonstrate that the developmental window for susceptibility to enduring untoward effects of general anesthetics may be much longer than previously appreciated, and those effects may include affective behaviors in addition to cognition.
Collapse
|
187
|
Ji J, Moquin A, Bertorelle F, KY Chang P, Antoine R, Luo J, McKinney RA, Maysinger D. Organotypic and primary neural cultures as models to assess effects of different gold nanostructures on glia and neurons. Nanotoxicology 2019; 13:285-304. [DOI: 10.1080/17435390.2018.1543468] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Jeff Ji
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Canada
| | - Alexandre Moquin
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Canada
| | - Franck Bertorelle
- CNRS, Institut Lumière Matière, Université Lyon Université Claude Bernard Lyon 1, Lyon, France
| | - Philip KY Chang
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Canada
| | - Rodolphe Antoine
- CNRS, Institut Lumière Matière, Université Lyon Université Claude Bernard Lyon 1, Lyon, France
| | - Julia Luo
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Canada
| | - R. Anne McKinney
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Canada
| | - Dusica Maysinger
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Canada
| |
Collapse
|
188
|
Delevich K, Thomas AW, Wilbrecht L. Adolescence and "Late Blooming" Synapses of the Prefrontal Cortex. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2019; 83:37-43. [PMID: 30674651 DOI: 10.1101/sqb.2018.83.037507] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The maturation of the prefrontal cortex (PFC) during adolescence is thought to be important for cognitive and affective development and mental health risk. Whereas many summaries of adolescent development have focused on dendritic spine pruning and gray matter thinning in the PFC during adolescence, we highlight recent rodent data from our laboratory and others to call attention to continued synapse formation and plasticity in the adolescent period in specific cell types and circuits. In particular, we highlight changes in inhibitory neurotransmission onto intratelencephalic (IT-type) projecting cortical neurons and late expansion of connectivity between the amygdala and PFC and the ventral tegmental area and PFC. Continued work on these "late blooming" synapses in specific cell types and circuits, and their interrelationships, will illuminate new opportunities for understanding and shaping the biology of adolescent development. We also address which aspects of adolescent PFC development are dependent on pubertal processes.
Collapse
Affiliation(s)
- Kristen Delevich
- Department of Psychology, University of California, Berkeley, California 94720, USA
| | - A Wren Thomas
- Department of Psychology, University of California, Berkeley, California 94720, USA.,Helen Wills Neuroscience Institute, University of California, Berkeley, California 94720, USA
| | - Linda Wilbrecht
- Department of Psychology, University of California, Berkeley, California 94720, USA.,Helen Wills Neuroscience Institute, University of California, Berkeley, California 94720, USA
| |
Collapse
|
189
|
Gao R, Asano SM, Upadhyayula S, Pisarev I, Milkie DE, Liu TL, Singh V, Graves A, Huynh GH, Zhao Y, Bogovic J, Colonell J, Ott CM, Zugates C, Tappan S, Rodriguez A, Mosaliganti KR, Sheu SH, Pasolli HA, Pang S, Xu CS, Megason SG, Hess H, Lippincott-Schwartz J, Hantman A, Rubin GM, Kirchhausen T, Saalfeld S, Aso Y, Boyden ES, Betzig E. Cortical column and whole-brain imaging with molecular contrast and nanoscale resolution. Science 2019; 363:eaau8302. [PMID: 30655415 PMCID: PMC6481610 DOI: 10.1126/science.aau8302] [Citation(s) in RCA: 196] [Impact Index Per Article: 39.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 11/30/2018] [Indexed: 12/20/2022]
Abstract
Optical and electron microscopy have made tremendous inroads toward understanding the complexity of the brain. However, optical microscopy offers insufficient resolution to reveal subcellular details, and electron microscopy lacks the throughput and molecular contrast to visualize specific molecular constituents over millimeter-scale or larger dimensions. We combined expansion microscopy and lattice light-sheet microscopy to image the nanoscale spatial relationships between proteins across the thickness of the mouse cortex or the entire Drosophila brain. These included synaptic proteins at dendritic spines, myelination along axons, and presynaptic densities at dopaminergic neurons in every fly brain region. The technology should enable statistically rich, large-scale studies of neural development, sexual dimorphism, degree of stereotypy, and structural correlations to behavior or neural activity, all with molecular contrast.
Collapse
Affiliation(s)
- Ruixuan Gao
- MIT Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
- McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Shoh M Asano
- MIT Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
- McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA
| | - Srigokul Upadhyayula
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
- Department of Cell Biology, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Avenue, Boston, MA 02115, USA
- Department of Pediatrics, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA
| | - Igor Pisarev
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Daniel E Milkie
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Tsung-Li Liu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Ved Singh
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Austin Graves
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Grace H Huynh
- MIT Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
| | - Yongxin Zhao
- MIT Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
| | - John Bogovic
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Jennifer Colonell
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Carolyn M Ott
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Christopher Zugates
- arivis AG, 1875 Connecticut Avenue NW, 10th floor, Washington, DC 20009, USA
| | - Susan Tappan
- MBF Bioscience, 185 Allen Brook Lane, Suite 101, Williston, VT 05495, USA
| | - Alfredo Rodriguez
- MBF Bioscience, 185 Allen Brook Lane, Suite 101, Williston, VT 05495, USA
| | - Kishore R Mosaliganti
- Department of Systems Biology, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA
| | - Shu-Hsien Sheu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - H Amalia Pasolli
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Song Pang
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - C Shan Xu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Sean G Megason
- Department of Systems Biology, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA
| | - Harald Hess
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | | | - Adam Hantman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Gerald M Rubin
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Tom Kirchhausen
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
- Department of Cell Biology, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, 200 Longwood Avenue, Boston, MA 02115, USA
- Department of Pediatrics, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA
| | - Stephan Saalfeld
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Yoshinori Aso
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Edward S Boyden
- MIT Media Lab, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA.
- McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA
- Department of Biological Engineering, MIT, Cambridge, MA 02139, USA
- MIT Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA
- Koch Institute, MIT, Cambridge, MA 02139, USA
| | - Eric Betzig
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
- Department of Physics, University of California, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, Berkeley, CA 94720, USA
- Helen Wills Neuroscience Institute, Berkeley, CA 94720, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| |
Collapse
|
190
|
Tendilla-Beltrán H, Antonio Vázquez-Roque R, Judith Vázquez-Hernández A, Garcés-Ramírez L, Flores G. Exploring the Dendritic Spine Pathology in a Schizophrenia-related Neurodevelopmental Animal Model. Neuroscience 2019; 396:36-45. [DOI: 10.1016/j.neuroscience.2018.11.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 10/17/2018] [Accepted: 11/08/2018] [Indexed: 01/17/2023]
|
191
|
OBI-NAGATA K, TEMMA Y, HAYASHI-TAKAGI A. Synaptic functions and their disruption in schizophrenia: From clinical evidence to synaptic optogenetics in an animal model. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2019; 95:179-197. [PMID: 31080187 PMCID: PMC6742729 DOI: 10.2183/pjab.95.014] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The adult human brain consists of approximately a hundred billion neurons, which are connected via synapses. The pattern and strength of the synaptic connections are constantly changing (synaptic plasticity), and these changes are considered to underlie learning, memory, and personality. Many psychiatric disorders have been related to disturbances in synaptogenesis and subsequent plasticity. In this review, we summarize findings of synaptic disturbance and its involvement in the pathogenesis and/or pathophysiology of psychiatric disorders. We will focus on schizophrenia, because this condition has a high proven heritability, which offers more unambiguous insights into the biological origins of not only schizophrenia but also related psychiatric disorders. To demonstrate the involvement of synaptopathy in psychiatric disorders, we discuss what knowledge is missing at the circuits level, and what new technologies are needed to achieve a comprehensive understanding of synaptopathy in psychiatric disorders.
Collapse
Affiliation(s)
- Kisho OBI-NAGATA
- Laboratory of Medical Neuroscience, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
| | - Yusuke TEMMA
- Laboratory of Medical Neuroscience, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
| | - Akiko HAYASHI-TAKAGI
- Laboratory of Medical Neuroscience, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
- PRESTO, Japan Science and Technology Agency, Kawaguchi, Japan
- Correspondence should be addressed: A. Hayashi-Takagi, Laboratory of Medical Neuroscience, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma 371-8512, Japan (e-mail: )
| |
Collapse
|
192
|
Boros BD, Greathouse KM, Gearing M, Herskowitz JH. Dendritic spine remodeling accompanies Alzheimer's disease pathology and genetic susceptibility in cognitively normal aging. Neurobiol Aging 2019; 73:92-103. [PMID: 30339964 PMCID: PMC6251733 DOI: 10.1016/j.neurobiolaging.2018.09.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 09/05/2018] [Accepted: 09/06/2018] [Indexed: 12/23/2022]
Abstract
Subtle alterations in dendritic spine morphology can induce marked effects on connectivity patterns of neuronal circuits and subsequent cognitive behavior. Past studies of rodent and nonhuman primate aging revealed reductions in spine density with concomitant alterations in spine morphology among pyramidal neurons in the prefrontal cortex. In this report, we visualized and digitally reconstructed the three-dimensional morphology of dendritic spines from the dorsolateral prefrontal cortex in cognitively normal individuals aged 40-94 years. Linear models defined relationships between spines and age, Mini-Mental State Examination, apolipoprotein E (APOE) ε4 allele status, and Alzheimer's disease (AD) pathology. Similar to findings in other mammals, spine density correlated negatively with human aging. Reduced spine head diameter associated with higher Mini-Mental State Examination scores. Individuals harboring an APOE ε4 allele displayed greater numbers of dendritic filopodia and structural alterations in thin spines. The presence of AD pathology correlated with increased spine length, reduced thin spine head diameter, and increased filopodia density. Our study reveals how spine morphology in the prefrontal cortex changes in human aging and highlights key structural alterations in selective spine populations that may promote cognitively normal function despite harboring the APOE ε4 allele or AD pathology.
Collapse
Affiliation(s)
- Benjamin D Boros
- Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, USA; Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Kelsey M Greathouse
- Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, USA; Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Marla Gearing
- Department of Pathology, Department of Neurology, Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Jeremy H Herskowitz
- Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, USA; Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.
| |
Collapse
|
193
|
Ziegler-Waldkirch S, Meyer-Luehmann M. The Role of Glial Cells and Synapse Loss in Mouse Models of Alzheimer's Disease. Front Cell Neurosci 2018; 12:473. [PMID: 30618627 PMCID: PMC6297249 DOI: 10.3389/fncel.2018.00473] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 11/20/2018] [Indexed: 11/13/2022] Open
Abstract
Synapse loss has detrimental effects on cellular communication, leading to network disruptions within the central nervous system (CNS) such as in Alzheimer’s disease (AD). AD is characterized by a progressive decline of memory function, cognition, neuronal and synapse loss. The two main neuropathological hallmarks are amyloid-β (Aβ) plaques and neurofibrillary tangles. In the brain of AD patients and in mouse models of AD several morphological and functional changes, such as microgliosis and astrogliosis around Aβ plaques, as well as dendritic and synaptic alterations, are associated with these lesions. In this review article, we will summarize the current literature on synapse loss in mouse models of AD and discuss current and prospective treatments for AD.
Collapse
Affiliation(s)
- Stephanie Ziegler-Waldkirch
- Department of Neurology, Medical Center-University of Freiburg, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Melanie Meyer-Luehmann
- Department of Neurology, Medical Center-University of Freiburg, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, Freiburg, Germany
| |
Collapse
|
194
|
Ketamine and selective activation of parvalbumin interneurons inhibit stress-induced dendritic spine elimination. Transl Psychiatry 2018; 8:272. [PMID: 30531859 PMCID: PMC6288154 DOI: 10.1038/s41398-018-0321-5] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 11/12/2018] [Accepted: 11/13/2018] [Indexed: 12/13/2022] Open
Abstract
Stress is a major risk factor for the onset of many psychiatric diseases. In rodent models, chronic stress induces depression and impairs excitatory neurotransmission. However, little is known about the effect of stress on synaptic circuitry during the development of behavioral symptoms. Using two-photon transcranial imaging, we studied the effect of repeated restraint stress on dendritic spine plasticity in the frontal cortex in vivo. We found that restraint stress induced dendritic spine loss by decreasing the rate of spine formation and increasing the rate of spine elimination. The N-methyl-D-aspartate receptor antagonist ketamine inhibited stress-induced spine loss mainly by protecting mushroom spines from elimination. Ketamine also induced re-formation of spines in close proximity to previously stress-eliminated spines. Electrophysiological and in vivo imaging experiments showed that ketamine enhanced activity of parvalbumin (PV) interneurons under stress and counterbalanced the stress-induced net loss of PV axonal boutons. In addition, selective chemogenetic excitation of PV interneurons mimicked the protective effects of ketamine on dendritic spines against stress. Collectively, our data provide new insights on the effects of ketamine on synaptic circuitry under stress and a possible mechanism to counteract stress-induced synaptic impairments through PV interneuron activation.
Collapse
|
195
|
Cortical dendritic spine development and plasticity: insights from in vivo imaging. Curr Opin Neurobiol 2018; 53:76-82. [DOI: 10.1016/j.conb.2018.06.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 06/04/2018] [Accepted: 06/05/2018] [Indexed: 01/14/2023]
|
196
|
Greathouse KM, Boros BD, Deslauriers JF, Henderson BW, Curtis KA, Gentry EG, Herskowitz JH. Distinct and complementary functions of rho kinase isoforms ROCK1 and ROCK2 in prefrontal cortex structural plasticity. Brain Struct Funct 2018; 223:4227-4241. [PMID: 30196430 PMCID: PMC6252131 DOI: 10.1007/s00429-018-1748-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 09/04/2018] [Indexed: 12/13/2022]
Abstract
Rho-associated protein kinases (ROCK) 1 and 2 are attractive drug targets for a range of neurologic disorders; however, a critical barrier to ROCK-based therapeutics is ambiguity over whether there are isoform-specific roles for ROCKs in neuronal structural plasticity. Here, we used a genetics approach to address this long-standing question by analyzing both male and female adult ROCK1+/- and ROCK2+/- mice compared to littermate controls. Individual pyramidal neurons in the medial prefrontal cortex (mPFC) were targeted for iontophoretic microinjection of fluorescent dye, followed by high-resolution confocal microscopy and neuronal 3D reconstructions for morphometry analysis. Increased apical and basal dendritic length and intersections were observed in ROCK1+/- but not ROCK2+/- mice. Although dendritic spine densities were comparable among genotypes, apical spine length was decreased in ROCK1+/- but increased in ROCK2+/- mice. Spine head and neck diameter were reduced similarly in ROCK1+/- and ROCK2+/- mice; however, certain spine morphologic subclasses were more affected than others in a genotype-dependent manner. Biochemical analyses of ROCK substrates in synaptic fractions revealed that phosphorylation of LIM kinase and cofilin were reduced in ROCK1+/- and ROCK2+/- mice, while phosphorylation of myosin light chain was decreased exclusively in ROCK1+/- mice. Collectively, these observations implicate ROCK1 as a novel regulatory factor of neuronal dendritic structure and detail distinct and complementary roles of ROCKs in mPFC dendritic spine structure.
Collapse
Affiliation(s)
- Kelsey M Greathouse
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, 35294, USA
| | - Benjamin D Boros
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, 35294, USA
| | - Josue F Deslauriers
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, 35294, USA
| | - Benjamin W Henderson
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, 35294, USA
| | - Kendall A Curtis
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, 35294, USA
| | - Erik G Gentry
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, 35294, USA
| | - Jeremy H Herskowitz
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, 1825 University Blvd., Birmingham, AL, 35294, USA.
| |
Collapse
|
197
|
Vadakkan KI. A potential mechanism for first-person internal sensation of memory provides evidence for the relationship between learning and LTP induction. Behav Brain Res 2018; 360:16-35. [PMID: 30502355 DOI: 10.1016/j.bbr.2018.11.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/26/2018] [Accepted: 11/26/2018] [Indexed: 12/21/2022]
Abstract
Studies conducted to verify learning-induced changes anticipated from Hebb's postulate led to the finding of long-term potentiation (LTP). Even though several correlations have been found between behavioural markers of memory retrieval and LTP, it is not known how memories are retrieved using learning-induced changes. In this context, the following non-correlated findings between learning and LTP induction provide constraints for discovering the mechanism: 1) Requirement of high stimulus intensity for LTP induction in contrast to what is expected for a learning mechanism, 2) Delay of at least 20 to 30 s from stimulation to LTP induction, in contrast to mere milliseconds for associative learning, and 3) A sudden drop in peak-potentiated effect (short-term potentiation) that matches with short-lasting changes expected during working memory and occurs only at the time of delayed LTP induction. When memories are viewed as first-person internal sensations, a newly uncovered mechanism provides explanation for the relationship between memory and LTP. This work interconnects large number of findings from the fields of neuroscience and psychology and provides a further verifiable mechanism of learning.
Collapse
|
198
|
Patel J, Lukkes JL, Shekhar A. Overview of genetic models of autism spectrum disorders. PROGRESS IN BRAIN RESEARCH 2018; 241:1-36. [PMID: 30447752 DOI: 10.1016/bs.pbr.2018.10.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Autism spectrum disorders (ASDs) are a group of neurodevelopment disorders that are characterized by heterogenous cognitive deficits and genetic factors. As more ASD risk genes are identified, genetic animal models have been developed to parse out the underlying neurobiological mechanisms of ASD. In this review, we discuss a subset of genetic models of ASD, focusing on those that have been widely studied and strongly linked to ASD. We focus our discussion of these models in the context of the theories and potential mechanisms of ASD, including disruptions in cell growth and proliferation, spine dynamics, synaptic transmission, excitation/inhibition balance, intracellular signaling, neuroinflammation, and behavior. In addition to ASD pathophysiology, we examine the limitations and challenges that genetic models pose for the study of ASD biology. We end with a review of innovative techniques and concepts of ASD pathology that can be further applied to and studied using genetic ASD models.
Collapse
Affiliation(s)
- Jheel Patel
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN, United States; Program in Medical Neuroscience, Paul and Carole Stark Neurosciences Research Institute, Indianapolis, IN, United States
| | - Jodi L Lukkes
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Anantha Shekhar
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN, United States; Program in Medical Neuroscience, Paul and Carole Stark Neurosciences Research Institute, Indianapolis, IN, United States; Indiana Clinical and Translation Sciences Institute, Indiana University School of Medicine, Indianapolis, IN, United States.
| |
Collapse
|
199
|
Mishra PK, Kutty BM, Laxmi TR. The impact of maternal separation and isolation stress during stress hyporesponsive period on fear retention and extinction recall memory from 5-week- to 1-year-old rats. Exp Brain Res 2018; 237:181-190. [PMID: 30374782 DOI: 10.1007/s00221-018-5411-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 10/21/2018] [Indexed: 12/16/2022]
Abstract
The purpose of the present study was to determine whether age would disrupt fear retention and extinction memory in rats pre-exposed to maternal separation and isolation stress; these rats are called MS rats. MS stress was induced by exposing rat pups into maternal separation followed by isolation stress from peer groups (MS) daily/6 h during stress hyporesponsive period, while controls rats that were undisturbed during this period are called NMS rats. 5, 8, 15 and 52 weeks later, these animals were exposed to classical fear conditioning test by pairing auditory stimulus (conditioned stimulus, CS+) with electric footshock. 24 h later, conditioned freezing response to CS+ was measured during fear retention, extinction and extinction recall trials. The normal ageing per se did not affect the formation of fear memory, retention and fear extinction memory. MS stress, on the other hand, disrupted fear memory at young adulthood age exhibiting increased freezing response to CS+ during retention test and reduced during fear extinction memory test when compared to NMS groups. On the other hand, rats at adolescence age exhibited reduced freezing during fear retention and enhanced freezing response to CS+ during extinction recall test. However, MS-induced changes in freezing response during fear retention and extinction tests were not seen in adulthood and 1-year-old age groups. These data demonstrate the young adulthood age is highly vulnerable to fear memory and extinction processes. The differences in freezing response to CS+ during fear conditioning from adolescence to old age, thus, appear to be related to the maturation of the limbic circuit.
Collapse
Affiliation(s)
- Pradeep Kumar Mishra
- Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, P.B. No. 2900, Bengaluru, Karnataka, 560 029, India
| | - Bindu M Kutty
- Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, P.B. No. 2900, Bengaluru, Karnataka, 560 029, India
| | - T R Laxmi
- Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, P.B. No. 2900, Bengaluru, Karnataka, 560 029, India.
| |
Collapse
|
200
|
Selective Loss of Thin Spines in Area 7a of the Primate Intraparietal Sulcus Predicts Age-Related Working Memory Impairment. J Neurosci 2018; 38:10467-10478. [PMID: 30355632 DOI: 10.1523/jneurosci.1234-18.2018] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 10/16/2018] [Accepted: 10/17/2018] [Indexed: 11/21/2022] Open
Abstract
Brodmann area 7a of the parietal cortex is active during working memory tasks in humans and nonhuman primates, but the composition and density of dendritic spines in area 7a and their relevance both to working memory and cognitive aging remain unexplored. Aged monkeys have impaired working memory, and we have previously shown that this age-induced cognitive impairment is partially mediated by a loss of thin spines in prefrontal cortex area 46, a critical area for working memory. Because area 46 is reciprocally connected with area 7a of the parietal cortex and 7a mediates visual attention integration, we hypothesized that thin spine density in area 7a would correlate with working memory performance as well. To investigate the synaptic profile of area 7a and its relevance to working memory and cognitive aging, we investigated differences in spine type and density in layer III pyramidal cells of area 7a in young and aged, male and female rhesus macaques (Macaca mulatta) that were cognitively assessed using the delayed response test of working memory. Area 7a shows age-related loss of thin spines, and thin spine density positively correlates with delayed response performance in aged monkeys. In contrast, these cells show no age-related changes in dendritic length or branching. These changes mirror age-related changes in area 46 but are distinct from other neocortical regions, such as V1. These findings support our hypothesis that cognitive aging is driven primarily by synaptic changes, and more specifically by changes in thin spines, in key association areas.SIGNIFICANCE STATEMENT This study advances our understanding of cognitive aging by demonstrating the relevance of area 7a thin spines to working memory performance. This study is the first to look at cognitive aging in the intraparietal sulcus, and also the first to report spine or dendritic measures for area 7a in either young adult or aged nonhuman primates. These results contribute to the hypothesis that thin spines support working memory performance and confirm our prior observation that cognitive aging is driven by synaptic changes rather than changes in dendritic morphology or neuron death. Importantly, these data show that age-related working memory changes are not limited to disruptions of the prefrontal cortex but also include an association region heavily interconnected with prefrontal cortex.
Collapse
|