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Koesters AG, Rich MM, Engisch KL. Homeostatic Synaptic Plasticity of Miniature Excitatory Postsynaptic Currents in Mouse Cortical Cultures Requires Neuronal Rab3A. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.14.544980. [PMID: 39071374 PMCID: PMC11275788 DOI: 10.1101/2023.06.14.544980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Following prolonged activity blockade, amplitudes of miniature excitatory postsynaptic currents (mEPSCs) increase, a form of plasticity termed "homeostatic synaptic plasticity." We previously showed that a presynaptic protein, the small GTPase Rab3A, is required for full expression of the increase in miniature endplate current amplitudes following prolonged blockade of action potential activity at the mouse neuromuscular junction in vivo (Wang et al., 2011), but it is unknown whether this form of Rab3A-dependent homeostatic plasticity shares any characteristics with central synapses. We show here that homeostatic synaptic plasticity of mEPSCs is impaired in mouse cortical neuron cultures prepared from Rab3A -/- and mutant mice expressing a single point mutation of Rab3A, Rab3A Earlybird mice. To determine if Rab3A is involved in the well-established homeostatic increase in postsynaptic AMPA-type receptors (AMPARs), we performed a series of experiments in which electrophysiological recordings of mEPSCs and confocal imaging of synaptic AMPAR immunofluorescence were assessed within the same cultures. We found that Rab3A was required for the increase in synaptic AMPARs following prolonged activity blockade, but the increase in mEPSC amplitudes was not always accompanied by an increase in postsynaptic AMPAR levels, suggesting other factors may contribute. Finally, we demonstrate that Rab3A is acting in neurons because only selective loss of Rab3A in neurons, not glia, disrupted the homeostatic increase in mEPSC amplitudes. This is the first demonstration that neuronal Rab3A is required for homeostatic synaptic plasticity and that it does so partially through regulation of the surface expression of AMPA receptors.
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2
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Shallow MC, Tian L, Lin H, Lefton KB, Chen S, Dougherty JD, Culver JP, Lambo ME, Hengen KB. At the onset of active whisking, the input layer of barrel cortex exhibits a 24 h window of increased excitability that depends on prior experience. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.04.597353. [PMID: 38895408 PMCID: PMC11185658 DOI: 10.1101/2024.06.04.597353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
The development of motor control over sensory organs is a critical milestone in sensory processing, enabling active exploration and shaping of the sensory environment. However, whether the onset of sensory organ motor control directly influences the development of corresponding sensory cortices remains unknown. Here, we exploit the late onset of whisking behavior in mice to address this question in the somatosensory system. Using ex vivo electrophysiology, we discovered a transient increase in the intrinsic excitability of excitatory neurons in layer IV of the barrel cortex, which processes whisker input, precisely coinciding with the onset of active whisking at postnatal day 14 (P14). This increase in neuronal gain was specific to layer IV, independent of changes in synaptic strength, and required prior sensory experience. Strikingly, the effect was not observed in layer II/III of the barrel cortex or in the visual cortex upon eye opening, suggesting a unique interaction between the development of active sensing and the thalamocortical input layer in the somatosensory system. Predictive modeling indicated that changes in active membrane conductances alone could reliably distinguish P14 neurons in control but not whisker-deprived hemispheres. Our findings demonstrate an experience-dependent, lamina-specific refinement of neuronal excitability tightly linked to the emergence of active whisking. This transient increase in the gain of the thalamic input layer coincides with a critical period for synaptic plasticity in downstream layers, suggesting a role in facilitating cortical maturation and sensory processing. Together, our results provide evidence for a direct interaction between the development of motor control and sensory cortex, offering new insights into the experience-dependent development and refinement of sensory systems. These findings have broad implications for understanding the interplay between motor and sensory development, and how the mechanisms of perception cooperate with behavior.
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Affiliation(s)
| | - Lucy Tian
- Department of Biology, Washington University in Saint Louis
| | - Hudson Lin
- Department of Biology, Washington University in Saint Louis
| | - Katheryn B Lefton
- Department of Biology, Washington University in Saint Louis
- Department of Neuroscience, Washington University in Saint Louis
| | - Siyu Chen
- Department of Genetics, Washington University in Saint Louis
| | | | - Joe P Culver
- Department of Radiology, Washington University in Saint Louis
| | - Mary E Lambo
- Department of Biology, Washington University in Saint Louis
| | - Keith B Hengen
- Department of Biology, Washington University in Saint Louis
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3
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Wen W, Turrigiano GG. Modular Arrangement of Synaptic and Intrinsic Homeostatic Plasticity within Visual Cortical Circuits. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.01.596982. [PMID: 38853882 PMCID: PMC11160741 DOI: 10.1101/2024.06.01.596982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Neocortical circuits use synaptic and intrinsic forms of homeostatic plasticity to stabilize key features of network activity, but whether these different homeostatic mechanisms act redundantly, or can be independently recruited to stabilize different network features, is unknown. Here we used pharmacological and genetic perturbations both in vitro and in vivo to determine whether synaptic scaling and intrinsic homeostatic plasticity (IHP) are arranged and recruited in a hierarchical or modular manner within L2/3 pyramidal neurons in rodent V1. Surprisingly, although the expression of synaptic scaling and IHP was dependent on overlapping trafficking pathways, they could be independently recruited by manipulating spiking activity or NMDAR signaling, respectively. Further, we found that changes in visual experience that affect NMDAR activation but not mean firing selectively trigger IHP, without recruiting synaptic scaling. These findings support a modular model in which synaptic and intrinsic homeostatic plasticity respond to and stabilize distinct aspects of network activity.
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Affiliation(s)
- Wei Wen
- Department of Biology, Brandeis University, Waltham, MA 02453, USA
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4
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Giri B, Kinsky N, Kaya U, Maboudi K, Abel T, Diba K. Sleep loss diminishes hippocampal reactivation and replay. Nature 2024; 630:935-942. [PMID: 38867049 DOI: 10.1038/s41586-024-07538-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 05/07/2024] [Indexed: 06/14/2024]
Abstract
Memories benefit from sleep1, and the reactivation and replay of waking experiences during hippocampal sharp-wave ripples (SWRs) are considered to be crucial for this process2. However, little is known about how these patterns are impacted by sleep loss. Here we recorded CA1 neuronal activity over 12 h in rats across maze exploration, sleep and sleep deprivation, followed by recovery sleep. We found that SWRs showed sustained or higher rates during sleep deprivation but with lower power and higher frequency ripples. Pyramidal cells exhibited sustained firing during sleep deprivation and reduced firing during sleep, yet their firing rates were comparable during SWRs regardless of sleep state. Despite the robust firing and abundance of SWRs during sleep deprivation, we found that the reactivation and replay of neuronal firing patterns was diminished during these periods and, in some cases, completely abolished compared to ad libitum sleep. Reactivation partially rebounded after recovery sleep but failed to reach the levels found in natural sleep. These results delineate the adverse consequences of sleep loss on hippocampal function at the network level and reveal a dissociation between the many SWRs elicited during sleep deprivation and the few reactivations and replays that occur during these events.
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Affiliation(s)
- Bapun Giri
- Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Nathaniel Kinsky
- Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Utku Kaya
- Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Kourosh Maboudi
- Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Ted Abel
- Department of Neuroscience and Pharmacology, Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
| | - Kamran Diba
- Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, MI, USA.
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA.
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5
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Suppermpool A, Lyons DG, Broom E, Rihel J. Sleep pressure modulates single-neuron synapse number in zebrafish. Nature 2024; 629:639-645. [PMID: 38693264 PMCID: PMC11096099 DOI: 10.1038/s41586-024-07367-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 03/27/2024] [Indexed: 05/03/2024]
Abstract
Sleep is a nearly universal behaviour with unclear functions1. The synaptic homeostasis hypothesis proposes that sleep is required to renormalize the increases in synaptic number and strength that occur during wakefulness2. Some studies examining either large neuronal populations3 or small patches of dendrites4 have found evidence consistent with the synaptic homeostasis hypothesis, but whether sleep merely functions as a permissive state or actively promotes synaptic downregulation at the scale of whole neurons is unclear. Here, by repeatedly imaging all excitatory synapses on single neurons across sleep-wake states of zebrafish larvae, we show that synapses are gained during periods of wake (either spontaneous or forced) and lost during sleep in a neuron-subtype-dependent manner. However, synapse loss is greatest during sleep associated with high sleep pressure after prolonged wakefulness, and lowest in the latter half of an undisrupted night. Conversely, sleep induced pharmacologically during periods of low sleep pressure is insufficient to trigger synapse loss unless adenosine levels are boosted while noradrenergic tone is inhibited. We conclude that sleep-dependent synapse loss is regulated by sleep pressure at the level of the single neuron and that not all sleep periods are equally capable of fulfilling the functions of synaptic homeostasis.
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Affiliation(s)
- Anya Suppermpool
- Department of Cell and Developmental Biology, University College London, London, UK
- UCL Ear Institute, University College London, London, UK
| | - Declan G Lyons
- Department of Cell and Developmental Biology, University College London, London, UK
| | - Elizabeth Broom
- Department of Cell and Developmental Biology, University College London, London, UK
| | - Jason Rihel
- Department of Cell and Developmental Biology, University College London, London, UK.
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6
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Vogt K, Kulkarni A, Pandey R, Dehnad M, Konopka G, Greene R. Sleep need driven oscillation of glutamate synaptic phenotype. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.05.578985. [PMID: 38370691 PMCID: PMC10871195 DOI: 10.1101/2024.02.05.578985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Sleep loss increases AMPA-synaptic strength and number in the neocortex. However, this is only part of the synaptic sleep loss response. We report increased AMPA/NMDA EPSC ratio in frontal-cortical pyramidal neurons of layers 2-3. Silent synapses are absent, decreasing the plastic potential to convert silent NMDA to active AMPA synapses. These sleep loss changes are recovered by sleep. Sleep genes are enriched for synaptic shaping cellular components controlling glutamate synapse phenotype, overlap with autism risk genes and are primarily observed in excitatory pyramidal neurons projecting intra-telencephalically. These genes are enriched with genes controlled by the transcription factor, MEF2c and its repressor, HDAC4. Thus, sleep genes under the influence of MEF2c and HDAC4, can provide a framework within which motor learning and training occurs mediated by sleep-dependent oscillation of glutamate-synaptic phenotypes.
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Affiliation(s)
- K.E. Vogt
- International Institute of Integrative Sleep Medicine, University of Tsukuba, Tsukuba, Japan
| | - A. Kulkarni
- Department of Neuroscience, Peter O’Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, United States
| | - R. Pandey
- Department of Psychiatry, Peter O’Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, United States
| | - M. Dehnad
- Department of Psychiatry, Peter O’Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, United States
| | - G. Konopka
- Department of Neuroscience, Peter O’Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, United States
| | - R.W. Greene
- International Institute of Integrative Sleep Medicine, University of Tsukuba, Tsukuba, Japan
- Department of Neuroscience, Peter O’Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, United States
- Department of Psychiatry, Peter O’Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, United States
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7
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Slutsky I. Linking activity dyshomeostasis and sleep disturbances in Alzheimer disease. Nat Rev Neurosci 2024; 25:272-284. [PMID: 38374463 DOI: 10.1038/s41583-024-00797-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2024] [Indexed: 02/21/2024]
Abstract
The presymptomatic phase of Alzheimer disease (AD) starts with the deposition of amyloid-β in the cortex and begins a decade or more before the emergence of cognitive decline. The trajectory towards dementia and neurodegeneration is shaped by the pathological load and the resilience of neural circuits to the effects of this pathology. In this Perspective, I focus on recent advances that have uncovered the vulnerability of neural circuits at early stages of AD to hyperexcitability, particularly when the brain is in a low-arousal states (such as sleep and anaesthesia). Notably, this hyperexcitability manifests before overt symptoms such as sleep and memory deficits. Using the principles of control theory, I analyse the bidirectional relationship between homeostasis of neuronal activity and sleep and propose that impaired activity homeostasis during sleep leads to hyperexcitability and subsequent sleep disturbances, whereas sleep disturbances mitigate hyperexcitability via negative feedback. Understanding the interplay among activity homeostasis, neuronal excitability and sleep is crucial for elucidating the mechanisms of vulnerability to and resilience against AD pathology and for identifying new therapeutic avenues.
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Affiliation(s)
- Inna Slutsky
- Department of Physiology and Pharmacology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
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8
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Stroh A, Schweiger S, Ramirez JM, Tüscher O. The selfish network: how the brain preserves behavioral function through shifts in neuronal network state. Trends Neurosci 2024; 47:246-258. [PMID: 38485625 DOI: 10.1016/j.tins.2024.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 01/31/2024] [Accepted: 02/19/2024] [Indexed: 04/12/2024]
Abstract
Neuronal networks possess the ability to regulate their activity states in response to disruptions. How and when neuronal networks turn from physiological into pathological states, leading to the manifestation of neuropsychiatric disorders, remains largely unknown. Here, we propose that neuronal networks intrinsically maintain network stability even at the cost of neuronal loss. Despite the new stable state being potentially maladaptive, neural networks may not reverse back to states associated with better long-term outcomes. These maladaptive states are often associated with hyperactive neurons, marking the starting point for activity-dependent neurodegeneration. Transitions between network states may occur rapidly, and in discrete steps rather than continuously, particularly in neurodegenerative disorders. The self-stabilizing, metastable, and noncontinuous characteristics of these network states can be mathematically described as attractors. Maladaptive attractors may represent a distinct pathophysiological entity that could serve as a target for new therapies and for fostering resilience.
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Affiliation(s)
- Albrecht Stroh
- Leibniz Institute for Resilience Research, Mainz, Germany; Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
| | - Susann Schweiger
- Leibniz Institute for Resilience Research, Mainz, Germany; Institute of Human Genetics, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany; Institute of Molecular Biology (IMB), Mainz, Germany
| | - Jan-Marino Ramirez
- Center for Integrative Brain Research at the Seattle Children's Research Institute, University of Washington, Seattle, USA
| | - Oliver Tüscher
- Leibniz Institute for Resilience Research, Mainz, Germany; Institute of Molecular Biology (IMB), Mainz, Germany; Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
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9
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Berry JA, Guhle DC, Davis RL. Active forgetting and neuropsychiatric diseases. Mol Psychiatry 2024:10.1038/s41380-024-02521-9. [PMID: 38532011 DOI: 10.1038/s41380-024-02521-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 03/04/2024] [Accepted: 03/06/2024] [Indexed: 03/28/2024]
Abstract
Recent and pioneering animal research has revealed the brain utilizes a variety of molecular, cellular, and network-level mechanisms used to forget memories in a process referred to as "active forgetting". Active forgetting increases behavioral flexibility and removes irrelevant information. Individuals with impaired active forgetting mechanisms can experience intrusive memories, distressing thoughts, and unwanted impulses that occur in neuropsychiatric diseases. The current evidence indicates that active forgetting mechanisms degrade, or mask, molecular and cellular memory traces created in synaptic connections of "engram cells" that are specific for a given memory. Combined molecular genetic/behavioral studies using Drosophila have uncovered a complex system of cellular active-forgetting pathways within engram cells that is regulated by dopamine neurons and involves dopamine-nitric oxide co-transmission and reception, endoplasmic reticulum Ca2+ signaling, and cytoskeletal remodeling machinery regulated by small GTPases. Some of these molecular cellular mechanisms have already been found to be conserved in mammals. Interestingly, some pathways independently regulate forgetting of distinct memory types and temporal phases, suggesting a multi-layering organization of forgetting systems. In mammals, active forgetting also involves modulation of memory trace synaptic strength by altering AMPA receptor trafficking. Furthermore, active-forgetting employs network level mechanisms wherein non-engram neurons, newly born-engram neurons, and glial cells regulate engram synapses in a state and experience dependent manner. Remarkably, there is evidence for potential coordination between the network and cellular level forgetting mechanisms. Finally, subjects with several neuropsychiatric diseases have been tested and shown to be impaired in active forgetting. Insights obtained from research on active forgetting in animal models will continue to enrich our understanding of the brain dysfunctions that occur in neuropsychiatric diseases.
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Affiliation(s)
- Jacob A Berry
- Department of Biological Sciences, University of Alberta, Edmonton, AL, T6G 2E9, Canada.
| | - Dana C Guhle
- Department of Biological Sciences, University of Alberta, Edmonton, AL, T6G 2E9, Canada
| | - Ronald L Davis
- Department of Neuroscience, UF Scripps Institute for Biomedical Innovation & Technology, 130 Scripps Way, Jupiter, FL, 33458, USA.
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10
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Weiss JT, Blundell MZ, Singh P, Donlea JM. Sleep deprivation drives brain-wide changes in cholinergic presynapse abundance in Drosophila melanogaster. Proc Natl Acad Sci U S A 2024; 121:e2312664121. [PMID: 38498719 PMCID: PMC10990117 DOI: 10.1073/pnas.2312664121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 02/19/2024] [Indexed: 03/20/2024] Open
Abstract
Sleep is an evolutionarily conserved state that supports brain functions, including synaptic plasticity, in species across the animal kingdom. Here, we examine the neuroanatomical and cell-type distribution of presynaptic scaling in the fly brain after sleep loss. We previously found that sleep loss drives accumulation of the active zone scaffolding protein Bruchpilot (BRP) within cholinergic Kenyon cells of the Drosophila melanogaster mushroom body (MB), but not in other classes of MB neurons. To test whether similar cell type-specific trends in plasticity occur broadly across the brain, we used a flp-based genetic reporter to label presynaptic BRP in cholinergic, dopaminergic, GABAergic, or glutamatergic neurons. We then collected whole-brain confocal image stacks of BRP intensity to systematically quantify BRP, a marker of presynapse abundance, across 37 neuropil regions of the central fly brain. Our results indicate that sleep loss, either by overnight (12-h) mechanical stimulation or chronic sleep disruption in insomniac mutants, broadly elevates cholinergic synapse abundance across the brain, while synapse abundance in neurons that produce other neurotransmitters undergoes weaker, if any, changes. Extending sleep deprivation to 24 h drives brain-wide upscaling in glutamatergic, but not other, synapses. Finally, overnight male-male social pairings induce increased BRP in excitatory synapses despite male-female pairings eliciting more waking activity, suggesting experience-specific plasticity. Within neurotransmitter class and waking context, BRP changes are similar across the 37 neuropil domains, indicating that similar synaptic scaling rules may apply across the brain during acute sleep loss and that sleep need may broadly alter excitatory-inhibitory balance in the central brain.
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Affiliation(s)
- Jacqueline T. Weiss
- Department of Neurobiology, David Geffen School of Medicine at University of California, Los Angeles, CA90095
- Neuroscience Interdepartmental Program, David Geffen School of Medicine, University of California, Los Angeles, CA90095
| | - Mei Z. Blundell
- Department of Neurobiology, David Geffen School of Medicine at University of California, Los Angeles, CA90095
| | - Prabhjit Singh
- Department of Neurobiology, David Geffen School of Medicine at University of California, Los Angeles, CA90095
| | - Jeffrey M. Donlea
- Department of Neurobiology, David Geffen School of Medicine at University of California, Los Angeles, CA90095
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11
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Koesters AG, Rich MM, Engisch KL. Diverging from the Norm: Reevaluating What Miniature Excitatory Postsynaptic Currents Tell Us about Homeostatic Synaptic Plasticity. Neuroscientist 2024; 30:49-70. [PMID: 35904350 DOI: 10.1177/10738584221112336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The idea that the nervous system maintains a set point of network activity and homeostatically returns to that set point in the face of dramatic disruption-during development, after injury, in pathologic states, and during sleep/wake cycles-is rapidly becoming accepted as a key plasticity behavior, placing it alongside long-term potentiation and depression. The dramatic growth in studies of homeostatic synaptic plasticity of miniature excitatory synaptic currents (mEPSCs) is attributable, in part, to the simple yet elegant mechanism of uniform multiplicative scaling proposed by Turrigiano and colleagues: that neurons sense their own activity and globally multiply the strength of every synapse by a single factor to return activity to the set point without altering established differences in synaptic weights. We have recently shown that for mEPSCs recorded from control and activity-blocked cultures of mouse cortical neurons, the synaptic scaling factor is not uniform but is close to 1 for the smallest mEPSC amplitudes and progressively increases as mEPSC amplitudes increase, which we term divergent scaling. Using insights gained from simulating uniform multiplicative scaling, we review evidence from published studies and conclude that divergent synaptic scaling is the norm rather than the exception. This conclusion has implications for hypotheses about the molecular mechanisms underlying synaptic scaling.
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Affiliation(s)
- Andrew G Koesters
- Department of Behavior, Cognition, and Neurophysiology, Environmental Health Effects Laboratory, Naval Medical Research Unit-Dayton, Wright-Patterson AFB, OH, USA
| | - Mark M Rich
- Department of Neuroscience, Cell Biology, and Physiology, College of Science and Mathematics, and Boonshoft School of Medicine, Wright State University, Dayton, OH, USA
| | - Kathrin L Engisch
- Department of Neuroscience, Cell Biology, and Physiology, College of Science and Mathematics, and Boonshoft School of Medicine, Wright State University, Dayton, OH, USA
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12
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Bottorff J, Padgett S, Turrigiano GG. Basal forebrain cholinergic activity is necessary for upward firing rate homeostasis in the rodent visual cortex. Proc Natl Acad Sci U S A 2024; 121:e2317987121. [PMID: 38147559 PMCID: PMC10769829 DOI: 10.1073/pnas.2317987121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 11/22/2023] [Indexed: 12/28/2023] Open
Abstract
Bidirectional homeostatic plasticity allows neurons and circuits to maintain stable firing in the face of developmental or learning-induced perturbations. In the primary visual cortex (V1), upward firing rate homeostasis (FRH) only occurs during active wake (AW) and downward during sleep, but how this behavioral state-dependent gating is accomplished is unknown. Here, we focus on how AW enables upward FRH in V1 of juvenile Long Evans rats. A major difference between quiet wake (QW), when upward FRH is absent, and AW, when it is present, is increased cholinergic (ACh) tone, and the main cholinergic projections to V1 arise from the horizontal diagonal band of the basal forebrain (HDB ACh). We therefore chemogenetically inhibited HDB ACh neurons while inducing upward homeostatic compensation using direct activity-suppression in V1. We found that synaptic scaling up and intrinsic homeostatic plasticity, two important cellular mediators of upward FRH, were both impaired when HDB ACh neurons were inhibited. Most strikingly, HDB ACh inhibition flipped the sign of intrinsic plasticity so that it became anti-homeostatic, and this effect was phenocopied by knockdown of the M1 ACh receptor in V1, indicating that this modulation of intrinsic plasticity is the result of direct actions of ACh within V1. Finally, we found that upward FRH induced by visual deprivation was completely prevented by HDB ACh inhibition. Together, our results show that HDB ACh modulation is a key enabler of upward homeostatic plasticity and FRH, and more broadly suggest that neuromodulatory inputs can segregate upward and downward homeostatic plasticity into distinct behavioral states.
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Affiliation(s)
- Juliet Bottorff
- Department of Biology and Neuroscience Program, Brandeis University, Waltham, MA02453
| | - Sydney Padgett
- Department of Biology and Neuroscience Program, Brandeis University, Waltham, MA02453
| | - Gina G. Turrigiano
- Department of Biology and Neuroscience Program, Brandeis University, Waltham, MA02453
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13
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Zhang P, Yan J, Wei J, Li Y, Sun C. Disrupted synaptic homeostasis and partial occlusion of associative long-term potentiation in the human cortex during social isolation. J Affect Disord 2024; 344:207-218. [PMID: 37832738 DOI: 10.1016/j.jad.2023.10.080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 09/22/2023] [Accepted: 10/09/2023] [Indexed: 10/15/2023]
Abstract
Social isolation often occurs in the military mission of soldiers but has increased in the general population since the COVID-19 epidemic. Overall synaptic homeostasis along with associative plasticity for the activity-dependent refinement of transmission across single synapses represent basic neural network function and adaptive behavior mechanisms. Here, we use electrophysiological and behavioral indices to non-invasively study the net synaptic strength and long-term potentiation (LTP)-like plasticity of humans in social isolation environments. The theta activity of electroencephalography (EEG) signals and transcranial magnetic stimulation (TMS) intensity to elicit a predefined amplitude of motor-evoked potential (MEP) demonstrate the disrupted synaptic homeostasis in the human cortex during social isolation. Furthermore, the induced MEP change by paired associative stimulation (PAS) demonstrates the partial occlusion of LTP-like plasticity, further behavior performances in a word-pair task are also identified as a potential index. Our study indicates that social isolation disrupts synaptic homeostasis and occludes associative LTP-like plasticity in the human cortex, decreasing behavior performance related to declarative memory.
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Affiliation(s)
- Peng Zhang
- School of Psychology, Beijing Key Laboratory of Learning and Cognition, Capital Normal University, Beijing 100048, China
| | - Juan Yan
- China CDC Key Laboratory of Radiological Protection and Nuclear Emergency, National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Beijing 100088, China
| | - Jiao Wei
- The First Affiliated Hospital of Shandong First Medical University, Neurosurgery, Jinan 250013, China
| | - Yane Li
- College of Mathematics and Computer Science, Zhejiang A&F University, Hangzhou 311300, China
| | - Chuancai Sun
- Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing 100191, China; The First Affiliated Hospital of Shandong First Medical University, Nephrology, Jinan 250013, China.
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14
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Radulescu CI, Doostdar N, Zabouri N, Melgosa-Ecenarro L, Wang X, Sadeh S, Pavlidi P, Airey J, Kopanitsa M, Clopath C, Barnes SJ. Age-related dysregulation of homeostatic control in neuronal microcircuits. Nat Neurosci 2023; 26:2158-2170. [PMID: 37919424 PMCID: PMC10689243 DOI: 10.1038/s41593-023-01451-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 09/06/2023] [Indexed: 11/04/2023]
Abstract
Neuronal homeostasis prevents hyperactivity and hypoactivity. Age-related hyperactivity suggests homeostasis may be dysregulated in later life. However, plasticity mechanisms preventing age-related hyperactivity and their efficacy in later life are unclear. We identify the adult cortical plasticity response to elevated activity driven by sensory overstimulation, then test how plasticity changes with age. We use in vivo two-photon imaging of calcium-mediated cellular/synaptic activity, electrophysiology and c-Fos-activity tagging to show control of neuronal activity is dysregulated in the visual cortex in late adulthood. Specifically, in young adult cortex, mGluR5-dependent population-wide excitatory synaptic weakening and inhibitory synaptogenesis reduce cortical activity following overstimulation. In later life, these mechanisms are downregulated, so that overstimulation results in synaptic strengthening and elevated activity. We also find overstimulation disrupts cognition in older but not younger animals. We propose that specific plasticity mechanisms fail in later life dysregulating neuronal microcircuit homeostasis and that the age-related response to overstimulation can impact cognitive performance.
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Affiliation(s)
- Carola I Radulescu
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Nazanin Doostdar
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Nawal Zabouri
- Department of Biomedical Engineering, Imperial College London, South Kensington Campus, London, UK
| | - Leire Melgosa-Ecenarro
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Xingjian Wang
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Sadra Sadeh
- Department of Biomedical Engineering, Imperial College London, South Kensington Campus, London, UK
- Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Pavlina Pavlidi
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Joe Airey
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | | | - Claudia Clopath
- Department of Biomedical Engineering, Imperial College London, South Kensington Campus, London, UK
| | - Samuel J Barnes
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK.
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15
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Pracucci E, Graham RT, Alberio L, Nardi G, Cozzolino O, Pillai V, Pasquini G, Saieva L, Walsh D, Landi S, Zhang J, Trevelyan AJ, Ratto GM. Daily rhythm in cortical chloride homeostasis underpins functional changes in visual cortex excitability. Nat Commun 2023; 14:7108. [PMID: 37925453 PMCID: PMC10625537 DOI: 10.1038/s41467-023-42711-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 10/19/2023] [Indexed: 11/06/2023] Open
Abstract
Cortical activity patterns are strongly modulated by fast synaptic inhibition mediated through ionotropic, chloride-conducting receptors. Consequently, chloride homeostasis is ideally placed to regulate activity. We therefore investigated the stability of baseline [Cl-]i in adult mouse neocortex, using in vivo two-photon imaging. We found a two-fold increase in baseline [Cl-]i in layer 2/3 pyramidal neurons, from day to night, with marked effects upon both physiological cortical processing and seizure susceptibility. Importantly, the night-time activity can be converted to the day-time pattern by local inhibition of NKCC1, while inhibition of KCC2 converts day-time [Cl-]i towards night-time levels. Changes in the surface expression and phosphorylation of the cation-chloride cotransporters, NKCC1 and KCC2, matched these pharmacological effects. When we extended the dark period by 4 h, mice remained active, but [Cl-]i was modulated as for animals in normal light cycles. Our data thus demonstrate a daily [Cl-]i modulation with complex effects on cortical excitability.
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Affiliation(s)
- Enrico Pracucci
- National Enterprise for nanoScience and nanoTechnology (NEST), Istituto Nanoscienze, Consiglio Nazionale delle Ricerche (CNR) and Scuola Normale Superiore Pisa, 56127, Pisa, Italy
| | - Robert T Graham
- Newcastle University Biosciences Institute, Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Laura Alberio
- Newcastle University Biosciences Institute, Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Gabriele Nardi
- National Enterprise for nanoScience and nanoTechnology (NEST), Istituto Nanoscienze, Consiglio Nazionale delle Ricerche (CNR) and Scuola Normale Superiore Pisa, 56127, Pisa, Italy
| | - Olga Cozzolino
- National Enterprise for nanoScience and nanoTechnology (NEST), Istituto Nanoscienze, Consiglio Nazionale delle Ricerche (CNR) and Scuola Normale Superiore Pisa, 56127, Pisa, Italy
| | - Vinoshene Pillai
- National Enterprise for nanoScience and nanoTechnology (NEST), Istituto Nanoscienze, Consiglio Nazionale delle Ricerche (CNR) and Scuola Normale Superiore Pisa, 56127, Pisa, Italy
| | - Giacomo Pasquini
- National Enterprise for nanoScience and nanoTechnology (NEST), Istituto Nanoscienze, Consiglio Nazionale delle Ricerche (CNR) and Scuola Normale Superiore Pisa, 56127, Pisa, Italy
| | - Luciano Saieva
- Newcastle University Biosciences Institute, Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Darren Walsh
- Newcastle University Biosciences Institute, Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Silvia Landi
- Institute of Neuroscience CNR, Pisa, Italy
- National Enterprise for nanoScience and nanoTechnology (NEST), Istituto Nanoscienze, Consiglio Nazionale delle Ricerche (CNR) and Scuola Normale Superiore Pisa, 56127, Pisa, Italy
| | - Jinwei Zhang
- Institute of Biomedical and Clinical Sciences, Medical School, College of Medicine and Institute of Health, University of Exeter, Hatherly Laboratories, Exeter, EX4 4PS, UK
- State Key Laboratory of Chemical Biology. Research Center of Chemical Kinomics, Shangai. Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Andrew J Trevelyan
- Newcastle University Biosciences Institute, Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.
| | - Gian-Michele Ratto
- National Enterprise for nanoScience and nanoTechnology (NEST), Istituto Nanoscienze, Consiglio Nazionale delle Ricerche (CNR) and Scuola Normale Superiore Pisa, 56127, Pisa, Italy.
- Institute of Neuroscience CNR, Pisa, Italy.
- Padova Neuroscience Center, Padova, Italy.
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16
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McGregor JN, Farris CA, Ensley S, Schneider A, Wang C, Liu Y, Tu J, Elmore H, Ronayne KD, Wessel R, Dyer EL, Bhaskaran-Nair K, Holtzman DM, Hengen KB. Tauopathy severely disrupts homeostatic set-points in emergent neural dynamics but not in the activity of individual neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.01.555947. [PMID: 37732214 PMCID: PMC10508737 DOI: 10.1101/2023.09.01.555947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
The homeostatic regulation of neuronal activity is essential for robust computation; key set-points, such as firing rate, are actively stabilized to compensate for perturbations. From this perspective, the disruption of brain function central to neurodegenerative disease should reflect impairments of computationally essential set-points. Despite connecting neurodegeneration to functional outcomes, the impact of disease on set-points in neuronal activity is unknown. Here we present a comprehensive, theory-driven investigation of the effects of tau-mediated neurodegeneration on homeostatic set-points in neuronal activity. In a mouse model of tauopathy, we examine 27,000 hours of hippocampal recordings during free behavior throughout disease progression. Contrary to our initial hypothesis that tauopathy would impact set-points in spike rate and variance, we found that cell-level set-points are resilient to even the latest stages of disease. Instead, we find that tauopathy disrupts neuronal activity at the network-level, which we quantify using both pairwise measures of neuron interactions as well as measurement of the network's nearness to criticality, an ideal computational regime that is known to be a homeostatic set-point. We find that shifts in network criticality 1) track with symptoms, 2) predict underlying anatomical and molecular pathology, 3) occur in a sleep/wake dependent manner, and 4) can be used to reliably classify an animal's genotype. Our data suggest that the critical set-point is intact, but that homeostatic machinery is progressively incapable of stabilizing hippocampal networks, particularly during waking. This work illustrates how neurodegenerative processes can impact the computational capacity of neurobiological systems, and suggest an important connection between molecular pathology, circuit function, and animal behavior.
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Affiliation(s)
- James N McGregor
- Department of Biology, Washington University in Saint Louis, St. Louis, MO, USA
| | - Clayton A Farris
- Department of Biology, Washington University in Saint Louis, St. Louis, MO, USA
| | - Sahara Ensley
- Department of Biology, Washington University in Saint Louis, St. Louis, MO, USA
| | - Aidan Schneider
- Department of Biology, Washington University in Saint Louis, St. Louis, MO, USA
| | - Chao Wang
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University in Saint Louis, St. Louis, MO, USA
- Institute for Brain Science and Disease, Chongqing Medical University, 400016, Chongqing, China
| | - Yuqi Liu
- Department of Biology, Washington University in Saint Louis, St. Louis, MO, USA
| | - Jianhong Tu
- Department of Biology, Washington University in Saint Louis, St. Louis, MO, USA
| | - Halla Elmore
- Department of Biology, Washington University in Saint Louis, St. Louis, MO, USA
| | - Keenan D Ronayne
- Department of Biology, Washington University in Saint Louis, St. Louis, MO, USA
| | - Ralf Wessel
- Department of Physics, Washington University in Saint Louis, St. Louis, MO, USA
| | - Eva L Dyer
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | | | - David M Holtzman
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University in Saint Louis, St. Louis, MO, USA
| | - Keith B Hengen
- Department of Biology, Washington University in Saint Louis, St. Louis, MO, USA
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17
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Benjamin AS, Kording KP. A role for cortical interneurons as adversarial discriminators. PLoS Comput Biol 2023; 19:e1011484. [PMID: 37768890 PMCID: PMC10538760 DOI: 10.1371/journal.pcbi.1011484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 08/31/2023] [Indexed: 09/30/2023] Open
Abstract
The brain learns representations of sensory information from experience, but the algorithms by which it does so remain unknown. One popular theory formalizes representations as inferred factors in a generative model of sensory stimuli, meaning that learning must improve this generative model and inference procedure. This framework underlies many classic computational theories of sensory learning, such as Boltzmann machines, the Wake/Sleep algorithm, and a more recent proposal that the brain learns with an adversarial algorithm that compares waking and dreaming activity. However, in order for such theories to provide insights into the cellular mechanisms of sensory learning, they must be first linked to the cell types in the brain that mediate them. In this study, we examine whether a subtype of cortical interneurons might mediate sensory learning by serving as discriminators, a crucial component in an adversarial algorithm for representation learning. We describe how such interneurons would be characterized by a plasticity rule that switches from Hebbian plasticity during waking states to anti-Hebbian plasticity in dreaming states. Evaluating the computational advantages and disadvantages of this algorithm, we find that it excels at learning representations in networks with recurrent connections but scales poorly with network size. This limitation can be partially addressed if the network also oscillates between evoked activity and generative samples on faster timescales. Consequently, we propose that an adversarial algorithm with interneurons as discriminators is a plausible and testable strategy for sensory learning in biological systems.
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Affiliation(s)
- Ari S. Benjamin
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Konrad P. Kording
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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18
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Calafate S, Özturan G, Thrupp N, Vanderlinden J, Santa-Marinha L, Morais-Ribeiro R, Ruggiero A, Bozic I, Rusterholz T, Lorente-Echeverría B, Dias M, Chen WT, Fiers M, Lu A, Vlaeminck I, Creemers E, Craessaerts K, Vandenbempt J, van Boekholdt L, Poovathingal S, Davie K, Thal DR, Wierda K, Oliveira TG, Slutsky I, Adamantidis A, De Strooper B, de Wit J. Early alterations in the MCH system link aberrant neuronal activity and sleep disturbances in a mouse model of Alzheimer's disease. Nat Neurosci 2023:10.1038/s41593-023-01325-4. [PMID: 37188873 DOI: 10.1038/s41593-023-01325-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 04/10/2023] [Indexed: 05/17/2023]
Abstract
Early Alzheimer's disease (AD) is associated with hippocampal hyperactivity and decreased sleep quality. Here we show that homeostatic mechanisms transiently counteract the increased excitatory drive to CA1 neurons in AppNL-G-F mice, but that this mechanism fails in older mice. Spatial transcriptomics analysis identifies Pmch as part of the adaptive response in AppNL-G-F mice. Pmch encodes melanin-concentrating hormone (MCH), which is produced in sleep-active lateral hypothalamic neurons that project to CA1 and modulate memory. We show that MCH downregulates synaptic transmission, modulates firing rate homeostasis in hippocampal neurons and reverses the increased excitatory drive to CA1 neurons in AppNL-G-F mice. AppNL-G-F mice spend less time in rapid eye movement (REM) sleep. AppNL-G-F mice and individuals with AD show progressive changes in morphology of CA1-projecting MCH axons. Our findings identify the MCH system as vulnerable in early AD and suggest that impaired MCH-system function contributes to aberrant excitatory drive and sleep defects, which can compromise hippocampus-dependent functions.
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Affiliation(s)
- Sara Calafate
- VIB Center for Brain & Disease Research, Leuven, Belgium.
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium.
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal.
| | - Gökhan Özturan
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Nicola Thrupp
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Jeroen Vanderlinden
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Luísa Santa-Marinha
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Rafaela Morais-Ribeiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Antonella Ruggiero
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ivan Bozic
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
| | - Thomas Rusterholz
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Blanca Lorente-Echeverría
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Marcelo Dias
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Wei-Ting Chen
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Mark Fiers
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Ashley Lu
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Ine Vlaeminck
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Eline Creemers
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Katleen Craessaerts
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Joris Vandenbempt
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Luuk van Boekholdt
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
- KU Leuven, Department of Otorhinolaryngology, Leuven, Belgium
| | - Suresh Poovathingal
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Kristofer Davie
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Dietmar Rudolf Thal
- Department of Imaging and Pathology, Laboratory of Neuropathology, and Leuven Brain Institute, KU-Leuven, O&N IV, Leuven, Belgium
- Department of Pathology, UZ Leuven, Leuven, Belgium
| | - Keimpe Wierda
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Tiago Gil Oliveira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Inna Slutsky
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Antoine Adamantidis
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Bart De Strooper
- VIB Center for Brain & Disease Research, Leuven, Belgium.
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium.
- UK Dementia Research Institute (UK DRI@UCL) at University College London, London, UK.
| | - Joris de Wit
- VIB Center for Brain & Disease Research, Leuven, Belgium.
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium.
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19
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Martinez JD, Donnelly MJ, Popke DS, Torres D, Wilson LG, Brancaleone WP, Sheskey S, Lin CM, Clawson BC, Jiang S, Aton SJ. Enriched binocular experience followed by sleep optimally restores binocular visual cortical responses in a mouse model of amblyopia. Commun Biol 2023; 6:408. [PMID: 37055505 PMCID: PMC10102075 DOI: 10.1038/s42003-023-04798-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 04/03/2023] [Indexed: 04/15/2023] Open
Abstract
Studies of primary visual cortex have furthered our understanding of amblyopia, long-lasting visual impairment caused by imbalanced input from the two eyes during childhood, which is commonly treated by patching the dominant eye. However, the relative impacts of monocular vs. binocular visual experiences on recovery from amblyopia are unclear. Moreover, while sleep promotes visual cortex plasticity following loss of input from one eye, its role in recovering binocular visual function is unknown. Using monocular deprivation in juvenile male mice to model amblyopia, we compared recovery of cortical neurons' visual responses after identical-duration, identical-quality binocular or monocular visual experiences. We demonstrate that binocular experience is quantitatively superior in restoring binocular responses in visual cortex neurons. However, this recovery was seen only in freely-sleeping mice; post-experience sleep deprivation prevented functional recovery. Thus, both binocular visual experience and subsequent sleep help to optimally renormalize bV1 responses in a mouse model of amblyopia.
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Affiliation(s)
- Jessy D Martinez
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Marcus J Donnelly
- Undergraduate Program in Neuroscience, University of Michigan, Ann Arbor, MI, USA
| | - Donald S Popke
- Undergraduate Program in Neuroscience, University of Michigan, Ann Arbor, MI, USA
| | - Daniel Torres
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Lydia G Wilson
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | | | - Sarah Sheskey
- Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Cheng-Mao Lin
- Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Brittany C Clawson
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Sha Jiang
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Sara J Aton
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
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20
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Giri B, Kaya U, Maboudi K, Abel T, Diba K. Sleep loss diminishes hippocampal reactivation and replay. RESEARCH SQUARE 2023:rs.3.rs-2540186. [PMID: 36824950 PMCID: PMC9949250 DOI: 10.21203/rs.3.rs-2540186/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Memories benefit from sleep, and sleep loss immediately following learning has a negative impact on subsequent memory storage. Several prominent hypotheses ascribe a central role to hippocampal sharp-wave ripples (SWRs), and the concurrent reactivation and replay of neuronal patterns from waking experience, in the offline memory consolidation process that occurs during sleep. However, little is known about how SWRs, reactivation, and replay are affected when animals are subjected to sleep deprivation. We performed long duration (~12 h), high-density silicon probe recordings from rat hippocampal CA1 neurons, in animals that were either sleeping or sleep deprived following exposure to a novel maze environment. We found that SWRs showed a sustained rate of activity during sleep deprivation, similar to or higher than in natural sleep, but with decreased amplitudes for the sharp-waves combined with higher frequencies for the ripples. Furthermore, while hippocampal pyramidal cells showed a log-normal distribution of firing rates during sleep, these distributions were negatively skewed with a higher mean firing rate in both pyramidal cells and interneurons during sleep deprivation. During SWRs, however, firing rates were remarkably similar between both groups. Despite the abundant quantity of SWRs and the robust firing activity during these events in both groups, we found that reactivation of neurons was either completely abolished or significantly diminished during sleep deprivation compared to sleep. Interestingly, reactivation partially rebounded upon recovery sleep, but failed to reach the levels characteristic of natural sleep. Similarly, the number of replays were significantly lower during sleep deprivation and recovery sleep compared to natural sleep. These results provide a network-level account for the negative impact of sleep loss on hippocampal function and demonstrate that sleep loss impacts memory storage by causing a dissociation between the amount of SWRs and the replays and reactivations that take place during these events.
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Affiliation(s)
- Bapun Giri
- Dept of Anesthesiology and Neuroscience Graduate Program, 1150 W Medical Center Dr, University of Michigan Medical School, Ann Arbor, MI 48109
- Dept of Psychology, University of Wisconsin-Milwaukee, PO Box 413, Milwaukee, WI 53201
| | - Utku Kaya
- Dept of Anesthesiology and Neuroscience Graduate Program, 1150 W Medical Center Dr, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Kourosh Maboudi
- Dept of Anesthesiology and Neuroscience Graduate Program, 1150 W Medical Center Dr, University of Michigan Medical School, Ann Arbor, MI 48109
- Dept of Psychology, University of Wisconsin-Milwaukee, PO Box 413, Milwaukee, WI 53201
| | - Ted Abel
- Department of Neuroscience and Pharmacology, Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa, USA
| | - Kamran Diba
- Dept of Anesthesiology and Neuroscience Graduate Program, 1150 W Medical Center Dr, University of Michigan Medical School, Ann Arbor, MI 48109
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21
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Lv Z, Li Y, Wang Y, Cong F, Li X, Cui W, Han C, Wei Y, Hong X, Liu Y, Ma L, Jiao Y, Zhang C, Li H, Jin M, Wang L, Ni S, Liu J. Safety and efficacy outcomes after intranasal administration of neural stem cells in cerebral palsy: a randomized phase 1/2 controlled trial. Stem Cell Res Ther 2023; 14:23. [PMID: 36759901 PMCID: PMC9910250 DOI: 10.1186/s13287-022-03234-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 06/05/2022] [Indexed: 02/11/2023] Open
Abstract
BACKGROUND Neural stem cells (NSCs) are believed to have the most therapeutic potential for neurological disorders because they can differentiate into various neurons and glial cells. This research evaluated the safety and efficacy of intranasal administration of NSCs in children with cerebral palsy (CP). The functional brain network (FBN) analysis based on electroencephalogram (EEG) and voxel-based morphometry (VBM) analysis based on T1-weighted images were performed to evaluate functional and structural changes in the brain. METHODS A total of 25 CP patients aged 3-12 years were randomly assigned to the treatment group (n = 15), which received an intranasal infusion of NSCs loaded with nasal patches and rehabilitation therapy, or the control group (n = 10) received rehabilitation therapy only. The primary endpoints were the safety (assessed by the incidence of adverse events (AEs), laboratory and imaging examinations) and the changes in the Gross Motor Function Measure-88 (GMFM-88), the Activities of Daily Living (ADL) scale, the Sleep Disturbance Scale for Children (SDSC), and some adapted scales. The secondary endpoints were the FBN and VBM analysis. RESULTS There were only four AEs happened during the 24-month follow-up period. There was no significant difference in the laboratory examinations before and after treatment, and the magnetic resonance imaging showed no abnormal nasal and intracranial masses. Compared to the control group, patients in the treatment group showed apparent improvements in GMFM-88 and ADL 24 months after treatment. Compared with the baseline, the scale scores of the Fine Motor Function, Sociability, Life Adaptability, Expressive Ability, GMFM-88, and ADL increased significantly in the treatment group 24 months after treatment, while the SDSC score decreased considerably. Compared with baseline, the FBN analysis showed a substantial decrease in brain network energy, and the VBM analysis showed a significant increase in gray matter volume in the treatment group after NSCs treatment. CONCLUSIONS Our results showed that intranasal administration of NSCs was well-tolerated and potentially beneficial in children with CP. TRIAL REGISTRATION The study was registered in ClinicalTrials.gov (NCT03005249, registered 29 December 2016, https://www. CLINICALTRIALS gov/ct2/show/NCT03005249 ) and the Medical Research Registration Information System (CMR-20161129-1003).
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Affiliation(s)
- Zhongyue Lv
- grid.452435.10000 0004 1798 9070Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, No. 193, Lianhe Road, Shahekou District, Dalian, 116011 Liaoning China ,Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian, Liaoning China
| | - Ying Li
- grid.452435.10000 0004 1798 9070Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, No. 193, Lianhe Road, Shahekou District, Dalian, 116011 Liaoning China ,Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian, Liaoning China
| | - Yachen Wang
- grid.452435.10000 0004 1798 9070Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, No. 193, Lianhe Road, Shahekou District, Dalian, 116011 Liaoning China ,Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian, Liaoning China
| | - Fengyu Cong
- grid.30055.330000 0000 9247 7930School of Biomedical Engineering, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, Liaoning Province, China ,grid.9681.60000 0001 1013 7965Faculty of Information Technology, University of Jyvaskyla, 40014 Jyvaskyla, Finland
| | - Xiaoyan Li
- grid.452435.10000 0004 1798 9070Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, No. 193, Lianhe Road, Shahekou District, Dalian, 116011 Liaoning China ,Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian, Liaoning China
| | - Wanming Cui
- grid.452435.10000 0004 1798 9070Department of Ent, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning China
| | - Chao Han
- grid.452435.10000 0004 1798 9070Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, No. 193, Lianhe Road, Shahekou District, Dalian, 116011 Liaoning China ,Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian, Liaoning China
| | - Yushan Wei
- grid.452435.10000 0004 1798 9070Scientific Research Department, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning China
| | - Xiaojun Hong
- grid.452435.10000 0004 1798 9070Neurophysiological Center, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning China
| | - Yong Liu
- grid.452435.10000 0004 1798 9070Department of Rehabilitation, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning China
| | - Luyi Ma
- grid.452435.10000 0004 1798 9070Department of Pediatrics, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning China
| | - Yang Jiao
- grid.452435.10000 0004 1798 9070Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, No. 193, Lianhe Road, Shahekou District, Dalian, 116011 Liaoning China ,Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian, Liaoning China ,grid.452435.10000 0004 1798 9070Department of Neurology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning China
| | - Chi Zhang
- grid.30055.330000 0000 9247 7930School of Biomedical Engineering, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, Liaoning Province, China
| | - Huanjie Li
- grid.30055.330000 0000 9247 7930School of Biomedical Engineering, Dalian University of Technology, Dalian, Liaoning China
| | - Mingyan Jin
- grid.30055.330000 0000 9247 7930School of Biomedical Engineering, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, Liaoning Province, China
| | - Liang Wang
- grid.452435.10000 0004 1798 9070Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, No. 193, Lianhe Road, Shahekou District, Dalian, 116011 Liaoning China ,Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian, Liaoning China
| | - Shiwei Ni
- grid.452435.10000 0004 1798 9070Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, No. 193, Lianhe Road, Shahekou District, Dalian, 116011 Liaoning China ,Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian, Liaoning China
| | - Jing Liu
- Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, No. 193, Lianhe Road, Shahekou District, Dalian, 116011, Liaoning, China. .,Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian, Liaoning, China.
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22
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Ge X, Wang L, Wang M, Pan L, Ye H, Zhu X, Fan S, Feng Q, Du Q, Wenhua Y, Ding Z. Alteration of brain network centrality in CTN patients after a single triggering pain. Front Neurosci 2023; 17:1109684. [PMID: 36875648 PMCID: PMC9978223 DOI: 10.3389/fnins.2023.1109684] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 01/25/2023] [Indexed: 02/18/2023] Open
Abstract
Objective The central nervous system may also be involved in the pathogenesis of classical trigeminal neuralgia (CTN). The present study aimed to explore the characteristics of static degree centrality (sDC) and dynamic degree centrality (dDC) at multiple time points after a single triggering pain in CTN patients. Materials and methods A total of 43 CTN patients underwent resting-state function magnetic resonance imaging (rs-fMRI) before triggering pain (baseline), within 5 s after triggering pain (triggering-5 s), and 30 min after triggering pain (triggering-30 min). Voxel-based degree centrality (DC) was used to assess the alteration of functional connection at different time points. Results The sDC values of the right caudate nucleus, fusiform gyrus, middle temporal gyrus, middle frontal gyrus, and orbital part were decreased in triggering-5 s and increased in triggering-30 min. The sDC value of the bilateral superior frontal gyrus were increased in triggering-5 s and decreased in triggering-30 min. The dDC value of the right lingual gyrus was gradually increased in triggering-5 s and triggering-30 min. Conclusion Both the sDC and dDC values were changed after triggering pain, and the brain regions were different between the two parameters, which supplemented each other. The brain regions which the sDC and dDC values were changing reflect the global brain function of CTN patients, and provides a basis for further exploration of the central mechanism of CTN.
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Affiliation(s)
- Xiuhong Ge
- Department of Radiology Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, Jiangsu, China.,Department of Radiology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, The Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou, China
| | - Luoyu Wang
- Department of Radiology Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, Jiangsu, China.,Department of Radiology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, The Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou, China
| | - Mengze Wang
- Department of Radiology Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, Jiangsu, China.,Department of Radiology, The Fourth Clinical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Lei Pan
- Department of Radiology Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, Jiangsu, China
| | - Haiqi Ye
- Department of Radiology Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, Jiangsu, China
| | - Xiaofen Zhu
- Department of Neurosurgery, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Sandra Fan
- Department of Radiology, The Fourth Clinical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Qi Feng
- Department of Neurosurgery, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Quan Du
- Department of Radiology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, The Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou, China
| | - Yu Wenhua
- Department of Radiology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, The Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhongxiang Ding
- Department of Radiology Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, Jiangsu, China.,Department of Radiology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, The Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou, China
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23
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Diering GH. Remembering and forgetting in sleep: Selective synaptic plasticity during sleep driven by scaling factors Homer1a and Arc. Neurobiol Stress 2022; 22:100512. [PMID: 36632309 PMCID: PMC9826981 DOI: 10.1016/j.ynstr.2022.100512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 12/01/2022] [Accepted: 12/29/2022] [Indexed: 01/02/2023] Open
Abstract
Sleep is a conserved and essential process that supports learning and memory. Synapses are a major target of sleep function and a locus of sleep need. Evidence in the literature suggests that the need for sleep has a cellular or microcircuit level basis, and that sleep need can accumulate within localized brain regions as a function of waking activity. Activation of sleep promoting kinases and accumulation of synaptic phosphorylation was recently shown to be part of the molecular basis for the localized sleep need. A prominent hypothesis in the field suggests that some benefits of sleep are mediated by a broad but selective weakening, or scaling-down, of synaptic strength during sleep in order to offset increased excitability from synaptic potentiation during wake. The literature also shows that synapses can be strengthened during sleep, raising the question of what molecular mechanisms may allow for selection of synaptic plasticity types during sleep. Here I describe mechanisms of action of the scaling factors Arc and Homer1a in selective plasticity and links with sleep need. Arc and Homer1a are induced in neurons in response to waking neuronal activity and accumulate with time spent awake. I suggest that during sleep, Arc and Homer1a drive broad weakening of synapses through homeostatic scaling-down, but in a manner that is sensitive to the plasticity history of individual synapses, based on patterned phosphorylation of synaptic proteins. Therefore, Arc and Homer1a may offer insights into the intricate links between a cellular basis of sleep need and memory consolidation during sleep.
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Affiliation(s)
- Graham H. Diering
- Department of Cell Biology and Physiology and the UNC Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA,Carolina Institute for Developmental Disabilities, USA,111 Mason Farm Road, 5200 Medical and Biomolecular Research Building, Chapel Hill, NC, 27599-7545, USA.
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24
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Miyamoto D. Neural circuit plasticity for complex non-declarative sensorimotor memory consolidation during sleep. Neurosci Res 2022; 189:37-43. [PMID: 36584925 DOI: 10.1016/j.neures.2022.12.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 12/28/2022]
Abstract
Evidence is accumulating that the brain actively consolidates long-term memory during sleep. Motor skill memory is a form of non-declarative procedural memory and can be coordinated with multi-sensory processing such as visual, tactile, and, auditory. Conversely, perception is affected by body movement signal from motor brain regions. Although both cortical and subcortical brain regions are involved in memory consolidation, cerebral cortex activity can be recorded and manipulated noninvasively or minimally invasively in humans and animals. NREM sleep, which is important for non-declarative memory consolidation, is characterized by slow and spindle waves representing thalamo-cortical population activity. In animals, electrophysiological recording, optical imaging, and manipulation approaches have revealed multi-scale cortical dynamics across learning and sleep. In the sleeping cortex, neural activity is affected by prior learning and neural circuits are continually reorganized. Here I outline how sensorimotor coordination is formed through awake learning and subsequent sleep.
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Affiliation(s)
- Daisuke Miyamoto
- Laboratory for Sleeping-Brain Dynamics, Research Center for Idling Brain Science, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
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25
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Catron MA, Howe RK, Besing GLK, St. John EK, Potesta CV, Gallagher MJ, Macdonald RL, Zhou C. Sleep slow-wave oscillations trigger seizures in a genetic epilepsy model of Dravet syndrome. Brain Commun 2022; 5:fcac332. [PMID: 36632186 PMCID: PMC9830548 DOI: 10.1093/braincomms/fcac332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 10/09/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
Sleep is the preferential period when epileptic spike-wave discharges appear in human epileptic patients, including genetic epileptic seizures such as Dravet syndrome with multiple mutations including SCN1A mutation and GABAA receptor γ2 subunit Gabrg2Q390X mutation in patients, which presents more severe epileptic symptoms in female patients than male patients. However, the seizure onset mechanism during sleep still remains unknown. Our previous work has shown that the sleep-like state-dependent homeostatic synaptic potentiation can trigger epileptic spike-wave discharges in one transgenic heterozygous Gabrg2+/Q390X knock-in mouse model.1 Here, using this heterozygous knock-in mouse model, we hypothesized that slow-wave oscillations themselves in vivo could trigger epileptic seizures. We found that epileptic spike-wave discharges in heterozygous Gabrg2+/Q390X knock-in mice exhibited preferential incidence during non-rapid eye movement sleep period, accompanied by motor immobility/facial myoclonus/vibrissal twitching and more frequent spike-wave discharge incidence appeared in female heterozygous knock-in mice than male heterozygous knock-in mice. Optogenetically induced slow-wave oscillations in vivo significantly increased epileptic spike-wave discharge incidence in heterozygous Gabrg2+/Q390X knock-in mice with longer duration of non-rapid eye movement sleep or quiet-wakeful states. Furthermore, suppression of slow-wave oscillation-related homeostatic synaptic potentiation by 4-(diethylamino)-benzaldehyde injection (i.p.) greatly attenuated spike-wave discharge incidence in heterozygous knock-in mice, suggesting that slow-wave oscillations in vivo did trigger seizure activity in heterozygous knock-in mice. Meanwhile, sleep spindle generation in wild-type littermates and heterozygous Gabrg2+/Q390X knock-in mice involved the slow-wave oscillation-related homeostatic synaptic potentiation that also contributed to epileptic spike-wave discharge generation in heterozygous Gabrg2+/Q390X knock-in mice. In addition, EEG spectral power of delta frequency (0.1-4 Hz) during non-rapid eye movement sleep was significantly larger in female heterozygous Gabrg2+/Q390X knock-in mice than that in male heterozygous Gabrg2+/Q390X knock-in mice, which likely contributes to the gender difference in seizure incidence during non-rapid eye movement sleep/quiet-wake states of human patients. Overall, all these results indicate that slow-wave oscillations in vivo trigger the seizure onset in heterozygous Gabrg2+/Q390X knock-in mice, preferentially during non-rapid eye movement sleep period and likely generate the sex difference in seizure incidence between male and female heterozygous Gabrg2+/Q390X knock-in mice.
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Affiliation(s)
- Mackenzie A Catron
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Neuroscience Graduate Program, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Rachel K Howe
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Gai-Linn K Besing
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Emily K St. John
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | | | - Martin J Gallagher
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Neuroscience Graduate Program, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Robert L Macdonald
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Neuroscience Graduate Program, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Chengwen Zhou
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Neuroscience Graduate Program, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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26
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Anastasiades PG, de Vivo L, Bellesi M, Jones MW. Adolescent sleep and the foundations of prefrontal cortical development and dysfunction. Prog Neurobiol 2022; 218:102338. [PMID: 35963360 PMCID: PMC7616212 DOI: 10.1016/j.pneurobio.2022.102338] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 08/04/2022] [Accepted: 08/08/2022] [Indexed: 11/17/2022]
Abstract
Modern life poses many threats to good-quality sleep, challenging brain health across the lifespan. Curtailed or fragmented sleep may be particularly damaging during adolescence, when sleep disruption by delayed chronotypes and societal pressures coincides with our brains preparing for adult life via intense refinement of neural connectivity. These vulnerabilities converge on the prefrontal cortex, one of the last brain regions to mature and a central hub of the limbic-cortical circuits underpinning decision-making, reward processing, social interactions and emotion. Even subtle disruption of prefrontal cortical development during adolescence may therefore have enduring impact. In this review, we integrate synaptic and circuit mechanisms, glial biology, sleep neurophysiology and epidemiology, to frame a hypothesis highlighting the implications of adolescent sleep disruption for the neural circuitry of the prefrontal cortex. Convergent evidence underscores the importance of acknowledging, quantifying and optimizing adolescent sleep's contributions to normative brain development and to lifelong mental health.
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Affiliation(s)
- Paul G Anastasiades
- University of Bristol, Translational Health Sciences, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK
| | - Luisa de Vivo
- University of Bristol, School of Physiology, Pharmacology & Neuroscience, University Walk, Bristol BS8 1TD, UK; University of Camerino, School of Pharmacy, via Gentile III Da Varano, Camerino 62032, Italy
| | - Michele Bellesi
- University of Bristol, School of Physiology, Pharmacology & Neuroscience, University Walk, Bristol BS8 1TD, UK; University of Camerino, School of Bioscience and Veterinary Medicine, via Gentile III Da Varano, Camerino 62032, Italy
| | - Matt W Jones
- University of Bristol, School of Physiology, Pharmacology & Neuroscience, University Walk, Bristol BS8 1TD, UK
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27
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Wang N, Langfelder P, Stricos M, Ramanathan L, Richman JB, Vaca R, Plascencia M, Gu X, Zhang S, Tamai TK, Zhang L, Gao F, Ouk K, Lu X, Ivanov LV, Vogt TF, Lu QR, Morton AJ, Colwell CS, Aaronson JS, Rosinski J, Horvath S, Yang XW. Mapping brain gene coexpression in daytime transcriptomes unveils diurnal molecular networks and deciphers perturbation gene signatures. Neuron 2022; 110:3318-3338.e9. [PMID: 36265442 PMCID: PMC9665885 DOI: 10.1016/j.neuron.2022.09.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 08/16/2022] [Accepted: 09/22/2022] [Indexed: 01/07/2023]
Abstract
Brain tissue transcriptomes may be organized into gene coexpression networks, but their underlying biological drivers remain incompletely understood. Here, we undertook a large-scale transcriptomic study using 508 wild-type mouse striatal tissue samples dissected exclusively in the afternoons to define 38 highly reproducible gene coexpression modules. We found that 13 and 11 modules are enriched in cell-type and molecular complex markers, respectively. Importantly, 18 modules are highly enriched in daily rhythmically expressed genes that peak or trough with distinct temporal kinetics, revealing the underlying biology of striatal diurnal gene networks. Moreover, the diurnal coexpression networks are a dominant feature of daytime transcriptomes in the mouse cortex. We next employed the striatal coexpression modules to decipher the striatal transcriptomic signatures from Huntington's disease models and heterozygous null mice for 52 genes, uncovering novel functions for Prkcq and Kdm4b in oligodendrocyte differentiation and bipolar disorder-associated Trank1 in regulating anxiety-like behaviors and nocturnal locomotion.
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Affiliation(s)
- Nan Wang
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Peter Langfelder
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Matthew Stricos
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Lalini Ramanathan
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Jeffrey B Richman
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Raymond Vaca
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Mary Plascencia
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Xiaofeng Gu
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Shasha Zhang
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - T Katherine Tamai
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Liguo Zhang
- Department of Pediatrics, Division of Experimental Hematology and Cancer Biology, Brain Tumor Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Fuying Gao
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Koliane Ouk
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Xiang Lu
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | | | - Thomas F Vogt
- CHDI Management /CHDI Foundation, Princeton, NJ, USA
| | - Qing Richard Lu
- Department of Pediatrics, Division of Experimental Hematology and Cancer Biology, Brain Tumor Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - A Jennifer Morton
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Christopher S Colwell
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; UCLA Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | | | - Jim Rosinski
- CHDI Management /CHDI Foundation, Princeton, NJ, USA
| | - Steve Horvath
- Department of Human Genetics, David Geffen School of Medicine at UCLA, University of California, Los Angeles, Los Angeles, CA, USA
| | - X William Yang
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience & Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
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28
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Tang X, Yang J, Zhu Y, Gong H, Sun H, Chen F, Guan Q, Yu L, Wang W, Zhang Z, Li L, Ma G, Wang X. High PSQI score is associated with the development of dyskinesia in Parkinson's disease. NPJ Parkinsons Dis 2022; 8:124. [PMID: 36175559 PMCID: PMC9522669 DOI: 10.1038/s41531-022-00391-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 09/06/2022] [Indexed: 11/09/2022] Open
Abstract
Dyskinesia is one of the most disabling motor complications in Parkinson's Disease (PD). Sleep is crucial to keep neural circuit homeostasis, and PD patients often suffer from sleep disturbance. However, few prospective studies have been conducted to investigate the association of sleep quality with dyskinesia in PD. The objective of the current study is to investigate the association between sleep quality and dyskinesia and build a prediction model for dyskinesia in PD. We prospectively followed a group of PD patients without dyskinesia at baseline for a maximum of 36 months. Univariable and multivariable Cox regression with stepwise variable selection was used to investigate risk factors for dyskinesia. The performance of the model was assessed by the time-dependent area under the receiver-operating characteristic curve (AUC). At the end of follow-up, 32.8% of patients developed dyskinesia. Patients with bad sleep quality had a significantly higher proportion of dyskinesia compared with those with good sleep quality (48.1% vs. 20.6%, p = 0.023). Multivariable Cox regression selected duration of PD, sleep quality, cognition, mood, and levodopa dose. Notably, high Pittsburgh sleep quality index (PSQI) score was independently associated with an increased risk of dyskinesia (HR = 2.96, 95% CI 1.05-8.35, p = 0.041). The model achieved a good discriminative ability, with the highest AUC being 0.83 at 35 months. Our results indicated that high PSQI score may increase the risk of developing dyskinesia in PD, implying that therapeutic intervention targeting improving sleep quality may be a promising approach to prevent or delay the development of dyskinesia in PD.
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Affiliation(s)
- Xiaohui Tang
- Department of Neurology, Shanghai Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Neurology,, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Neurology, Zhabei Central Hospital, Jing'an District, Shanghai, China
| | - Jingyun Yang
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Yining Zhu
- School of Mathematical Sciences, Fudan University, Yangpu District, Shanghai, China
| | - Haiyan Gong
- Department of Neurology, Shanghai Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Hui Sun
- Department of Neurology, Shanghai Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Fan Chen
- Department of Neurology, Shanghai Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Qiang Guan
- Department of Neurology, Shanghai Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Lijia Yu
- Department of Neurology,, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Weijia Wang
- Department of Neurology, Suzhou BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Suzhou, Jiangsu Province, China
| | - Zengping Zhang
- Department of Neurology, Suzhou BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Suzhou, Jiangsu Province, China
| | - Li Li
- Department of Neurology, Suzhou BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Suzhou, Jiangsu Province, China
| | - Guozhao Ma
- Department of Neurology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China.
- Department of Neurology, Shandong Provincial Hospital affiliated to Shandong First Medical University, Jinan, Shandong Province, China.
| | - Xijin Wang
- Department of Neurology, Shanghai Tongji Hospital, School of Medicine, Tongji University, Shanghai, China.
- Department of Neurology,, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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Ge X, Wang L, Pan L, Ye H, Zhu X, Fan S, Feng Q, Yu W, Ding Z. Amplitude of low-frequency fluctuation after a single-trigger pain in patients with classical trigeminal neuralgia. J Headache Pain 2022; 23:117. [PMID: 36076162 PMCID: PMC9461270 DOI: 10.1186/s10194-022-01488-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 08/24/2022] [Indexed: 11/29/2022] Open
Abstract
Objective This study aimed to explore the central mechanism of classical trigeminal neuralgia (CTN) by analyzing the static amplitude of low-frequency fluctuation (sALFF) and dynamic amplitude of low-frequency fluctuation (dALFF) in patients with CTN before and after a single-trigger pain. Methods This study included 48 patients (37 women and 11 men, age 55.65 ± 11.41 years) with CTN. All participants underwent 3D-T1WI and three times resting-state functional magnetic resonance imaging. The images were taken before stimulating the trigger zone (baseline), within 5 s after stimulating the trigger zone (triggering-5 s), and in the 30th minute after stimulating the trigger zone (triggering-30 min). The differences between the three measurements were analyzed using a repeated-measures analysis of variance. Results The sALFF values of the bilateral middle occipital gyrus and right cuneus gradually increased, and the values of the left posterior cingulum gyrus and bilateral superior frontal gyrus gradually decreased in triggering-5 s and triggering-30 min. The values of the right middle temporal gyrus and right thalamus decreased in triggering-5 s and subsequently increased in triggering-30 min. The sALFF values of the left superior temporal gyrus increased in triggering-5 s and then decreased in triggering-30 min. The dALFF values of the right fusiform gyrus, bilateral lingual gyrus, left middle temporal gyrus, and right cuneus gyrus gradually increased in both triggering-5 s and triggering-30 min. Conclusions The sALFF and dALFF values changed differently in multiple brain regions in triggering-5 s and triggering-30 min of CTN patients after a single trigger of pain, and dALFF is complementary to sALFF. The results might help explore the therapeutic targets for relieving pain and improving the quality of life of patients with CTN. Supplementary Information The online version contains supplementary material available at 10.1186/s10194-022-01488-8.
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Affiliation(s)
- Xiuhong Ge
- Department of Radiology, Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310000, P.R. China.,Department of Radiology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou City, 310006, China
| | - Luoyu Wang
- Department of Radiology, Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310000, P.R. China.,Department of Radiology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou City, 310006, China
| | - Lei Pan
- Department of Radiology, Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310000, P.R. China
| | - Haiqi Ye
- Department of Radiology, Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310000, P.R. China
| | - Xiaofen Zhu
- Department of Radiology, Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310000, P.R. China
| | - Sandra Fan
- Zhejiang Chinese Medical University, Hangzhou, 310000, P.R. China
| | - Qi Feng
- Department of Radiology, Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310000, P.R. China
| | - Wenhua Yu
- Department of Neurosurgery, Hangzhou First People's Hospital, Zhejiang University School of Medicine, No.261, Huansha Road, Shangcheng Distric, Hangzhou, 310000, P.R. China.
| | - Zhongxiang Ding
- Department of Radiology, Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310000, P.R. China. .,Department of Radiology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou City, 310006, China.
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IGF-1 receptor regulates upward firing rate homeostasis via the mitochondrial calcium uniporter. Proc Natl Acad Sci U S A 2022; 119:e2121040119. [PMID: 35943986 PMCID: PMC9388073 DOI: 10.1073/pnas.2121040119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
An emerging hypothesis is that neuronal circuits homeostatically maintain a stable spike rate despite continuous environmental changes. This firing rate homeostasis is believed to confer resilience to neurodegeneration and cognitive decline. We show that insulin-like growth factor-1 receptor (IGF-1R) is necessary for homeostatic response of mean firing rate to inactivity, termed “upward firing rate homeostasis.” We show that its mechanism of action is to couple spike bursts with downstream mitochondrial Ca2+ influx via the mitochondrial calcium uniporter complex (MCUc). We propose that MCUc is a homeostatic Ca2+ sensor that triggers the integrated homeostatic response. Firing rate homeostasis may be the principal mechanism by which IGF-1R regulates aging and neurodevelopmental and neurodegenerative disorders. Regulation of firing rate homeostasis constitutes a fundamental property of central neural circuits. While intracellular Ca2+ has long been hypothesized to be a feedback control signal, the molecular machinery enabling a network-wide homeostatic response remains largely unknown. We show that deletion of insulin-like growth factor-1 receptor (IGF-1R) limits firing rate homeostasis in response to inactivity, without altering the distribution of baseline firing rates. The deficient firing rate homeostatic response was due to disruption of both postsynaptic and intrinsic plasticity. At the cellular level, we detected a fraction of IGF-1Rs in mitochondria, colocalized with the mitochondrial calcium uniporter complex (MCUc). IGF-1R deletion suppressed transcription of the MCUc members and burst-evoked mitochondrial Ca2+ (mitoCa2+) by weakening mitochondria-to-cytosol Ca2+ coupling. Overexpression of either mitochondria-targeted IGF-1R or MCUc in IGF-1R–deficient neurons was sufficient to rescue the deficits in burst-to-mitoCa2+ coupling and firing rate homeostasis. Our findings indicate that mitochondrial IGF-1R is a key regulator of the integrated homeostatic response by tuning the reliability of burst transfer by MCUc. Based on these results, we propose that MCUc acts as a homeostatic Ca2+ sensor. Faulty activation of MCUc may drive dysregulation of firing rate homeostasis in aging and in brain disorders associated with aberrant IGF-1R/MCUc signaling.
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31
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Wong NF, Xu-Friedman MA. Induction of Activity-Dependent Plasticity at Auditory Nerve Synapses. J Neurosci 2022; 42:6211-6220. [PMID: 35790402 PMCID: PMC9374128 DOI: 10.1523/jneurosci.0666-22.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/26/2022] [Accepted: 06/25/2022] [Indexed: 11/21/2022] Open
Abstract
Exposure to nontraumatic noise in vivo drives long-lasting changes in auditory nerve synapses, which may influence hearing, but the induction mechanisms are not known. We mimicked activity in acute slices of the cochlear nucleus from mice of both sexes by treating them with high potassium, after which voltage-clamp recordings from bushy cells indicated that auditory nerve synapses had reduced EPSC amplitude, quantal size, and vesicle release probability (P r). The effects of high potassium were prevented by blockers of nitric oxide (NO) synthase and protein kinase A. Treatment with the NO donor, PAPA-NONOate, also decreased P r, suggesting NO plays a central role in inducing synaptic changes. To identify the source of NO, we activated auditory nerve fibers specifically using optogenetics. Strobing for 2 h led to decreased EPSC amplitude and P r, which was prevented by antagonists against ionotropic glutamate receptors and NO synthase. This suggests that the activation of AMPA and NMDA receptors in postsynaptic targets of auditory nerve fibers drives release of NO, which acts retrogradely to cause long-term changes in synaptic function in auditory nerve synapses. This may provide insight into preventing or treating disorders caused by noise exposure.SIGNIFICANCE STATEMENT Auditory nerve fibers undergo long-lasting changes in synaptic properties in response to noise exposure in vivo, which may contribute to changes in hearing. Here, we investigated the cellular mechanisms underlying induction of synaptic changes using high potassium and optogenetic stimulation in vitro and identified important signaling pathways using pharmacology. Our results suggest that auditory nerve activity drives postsynaptic depolarization through AMPA and NMDA receptors, leading to the release of nitric oxide, which acts retrogradely to regulate presynaptic neurotransmitter release. These experiments revealed that auditory nerve synapses are unexpectedly sensitive to activity and can show dramatic, long-lasting changes in a few hours that could affect hearing.
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Affiliation(s)
- Nicole F Wong
- Department of Biological Sciences, University at Buffalo, State University of New York, Buffalo, New York 14260
| | - Matthew A Xu-Friedman
- Department of Biological Sciences, University at Buffalo, State University of New York, Buffalo, New York 14260
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32
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Inactivity and Ca 2+ signaling regulate synaptic compensation in motoneurons following hibernation in American bullfrogs. Sci Rep 2022; 12:11610. [PMID: 35803955 PMCID: PMC9270477 DOI: 10.1038/s41598-022-15525-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 06/24/2022] [Indexed: 11/24/2022] Open
Abstract
Neural networks tune synaptic and cellular properties to produce stable activity. One form of homeostatic regulation involves scaling the strength of synapses up or down in a global and multiplicative manner to oppose activity disturbances. In American bullfrogs, excitatory synapses scale up to regulate breathing motor function after inactivity in hibernation, connecting homeostatic compensation to motor behavior. In traditional models of homeostatic synaptic plasticity, inactivity is thought to increase synaptic strength via mechanisms that involve reduced Ca2+ influx through voltage-gated channels. Therefore, we tested whether pharmacological inactivity and inhibition of voltage-gated Ca2+ channels are sufficient to drive synaptic compensation in this system. For this, we chronically exposed ex vivo brainstem preparations containing the intact respiratory network to tetrodotoxin (TTX) to stop activity and nimodipine to block L-type Ca2+ channels. We show that hibernation and TTX similarly increased motoneuron synaptic strength and that hibernation occluded the response to TTX. In contrast, inhibiting L-type Ca2+ channels did not upregulate synaptic strength but disrupted the apparent multiplicative scaling of synaptic compensation typically observed in response to hibernation. Thus, inactivity drives up synaptic strength through mechanisms that do not rely on reduced L-type channel function, while Ca2+ signaling associated with the hibernation environment independently regulates the balance of synaptic weights. Altogether, these results point to multiple feedback signals for shaping synaptic compensation that gives rise to proper network function during environmental challenges in vivo.
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Renouard L, Hayworth C, Rempe M, Clegern W, Wisor J, Frank MG. REM sleep promotes bidirectional plasticity in developing visual cortex in vivo. Neurobiol Sleep Circadian Rhythms 2022; 12:100076. [PMID: 35592144 PMCID: PMC9112011 DOI: 10.1016/j.nbscr.2022.100076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/20/2022] [Accepted: 04/28/2022] [Indexed: 11/23/2022] Open
Abstract
Sleep is required for the full expression of plasticity during the visual critical period (CP). However, the precise role of rapid-eye-movement (REM) sleep in this process is undetermined. Previous studies in rodents indicate that REM sleep weakens cortical circuits following MD, but this has been explored in only one class of cortical neuron (layer 5 apical dendrites). We investigated the role of REM sleep in ocular dominance plasticity (ODP) in layer 2/3 neurons using 2-photon calcium imaging in awake CP mice. In contrast to findings in layer 5 neurons, we find that REM sleep promotes changes consistent with synaptic strengthening and weakening. This supports recent suggestions that the effects of sleep on plasticity are highly dependent upon the type of circuit and preceding waking experience.
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Affiliation(s)
- Leslie Renouard
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, HSB 280M, Spokane, WA, 99223, USA
| | - Christopher Hayworth
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, HSB 280M, Spokane, WA, 99223, USA
| | - Michael Rempe
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, HSB 280M, Spokane, WA, 99223, USA
| | - Will Clegern
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, HSB 280M, Spokane, WA, 99223, USA
| | - Jonathan Wisor
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, HSB 280M, Spokane, WA, 99223, USA
| | - Marcos G. Frank
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, HSB 280M, Spokane, WA, 99223, USA
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Ramos R, Wu CH, Turrigiano GG. Strong Aversive Conditioning Triggers a Long-Lasting Generalized Aversion. Front Cell Neurosci 2022; 16:854315. [PMID: 35295904 PMCID: PMC8918528 DOI: 10.3389/fncel.2022.854315] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 02/11/2022] [Indexed: 11/29/2022] Open
Abstract
Generalization is an adaptive mnemonic process in which an animal can leverage past learning experiences to navigate future scenarios, but overgeneralization is a hallmark feature of anxiety disorders. Therefore, understanding the synaptic plasticity mechanisms that govern memory generalization and its persistence is an important goal. Here, we demonstrate that strong CTA conditioning results in a long-lasting generalized aversion that persists for at least 2 weeks. Using brain slice electrophysiology and activity-dependent labeling of the conditioning-active neuronal ensemble within the gustatory cortex, we find that strong CTA conditioning induces a long-lasting increase in synaptic strengths that occurs uniformly across superficial and deep layers of GC. Repeated exposure to salt, the generalized tastant, causes a rapid attenuation of the generalized aversion that correlates with a reversal of the CTA-induced increases in synaptic strength. Unlike the uniform strengthening that happens across layers, reversal of the generalized aversion results in a more pronounced depression of synaptic strengths in superficial layers. Finally, the generalized aversion and its reversal do not impact the acquisition and maintenance of the aversion to the conditioned tastant (saccharin). The strong correlation between the generalized aversion and synaptic strengthening, and the reversal of both in superficial layers by repeated salt exposure, strongly suggests that the synaptic changes in superficial layers contribute to the formation and reversal of the generalized aversion. In contrast, the persistence of synaptic strengthening in deep layers correlates with the persistence of CTA. Taken together, our data suggest that layer-specific synaptic plasticity mechanisms separately govern the persistence and generalization of CTA memory.
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Weiss JT, Donlea JM. Roles for Sleep in Neural and Behavioral Plasticity: Reviewing Variation in the Consequences of Sleep Loss. Front Behav Neurosci 2022; 15:777799. [PMID: 35126067 PMCID: PMC8810646 DOI: 10.3389/fnbeh.2021.777799] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 12/16/2021] [Indexed: 12/13/2022] Open
Abstract
Sleep is a vital physiological state that has been broadly conserved across the evolution of animal species. While the precise functions of sleep remain poorly understood, a large body of research has examined the negative consequences of sleep loss on neural and behavioral plasticity. While sleep disruption generally results in degraded neural plasticity and cognitive function, the impact of sleep loss can vary widely with age, between individuals, and across physiological contexts. Additionally, several recent studies indicate that sleep loss differentially impacts distinct neuronal populations within memory-encoding circuitry. These findings indicate that the negative consequences of sleep loss are not universally shared, and that identifying conditions that influence the resilience of an organism (or neuron type) to sleep loss might open future opportunities to examine sleep's core functions in the brain. Here, we discuss the functional roles for sleep in adaptive plasticity and review factors that can contribute to individual variations in sleep behavior and responses to sleep loss.
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Affiliation(s)
- Jacqueline T. Weiss
- Department of Neurobiology, David Geffen School of Medicine at University of California, Los Angeles, Los Angeles, CA, United States
- Neuroscience Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA, United States
| | - Jeffrey M. Donlea
- Department of Neurobiology, David Geffen School of Medicine at University of California, Los Angeles, Los Angeles, CA, United States
- *Correspondence: Jeffrey M. Donlea
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Padamsey Z, Katsanevaki D, Dupuy N, Rochefort NL. Neocortex saves energy by reducing coding precision during food scarcity. Neuron 2022; 110:280-296.e10. [PMID: 34741806 PMCID: PMC8788933 DOI: 10.1016/j.neuron.2021.10.024] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 09/07/2021] [Accepted: 10/15/2021] [Indexed: 11/21/2022]
Abstract
Information processing is energetically expensive. In the mammalian brain, it is unclear how information coding and energy use are regulated during food scarcity. Using whole-cell recordings and two-photon imaging in layer 2/3 mouse visual cortex, we found that food restriction reduced AMPA receptor conductance, reducing synaptic ATP use by 29%. Neuronal excitability was nonetheless preserved by a compensatory increase in input resistance and a depolarized resting potential. Consequently, neurons spiked at similar rates as controls but spent less ATP on underlying excitatory currents. This energy-saving strategy had a cost because it amplified the variability of visually-evoked subthreshold responses, leading to a 32% broadening of orientation tuning and impaired fine visual discrimination. This reduction in coding precision was associated with reduced levels of the fat mass-regulated hormone leptin and was restored by exogenous leptin supplementation. Our findings reveal that metabolic state dynamically regulates the energy spent on coding precision in neocortex.
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Affiliation(s)
- Zahid Padamsey
- Centre for Discovery Brain Sciences, School of Biomedical Sciences, University of Edinburgh, Edinburgh EH8 9XD, UK.
| | - Danai Katsanevaki
- Centre for Discovery Brain Sciences, School of Biomedical Sciences, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Nathalie Dupuy
- Centre for Discovery Brain Sciences, School of Biomedical Sciences, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Nathalie L Rochefort
- Centre for Discovery Brain Sciences, School of Biomedical Sciences, University of Edinburgh, Edinburgh EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, UK.
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Zarhin D, Atsmon R, Ruggiero A, Baeloha H, Shoob S, Scharf O, Heim LR, Buchbinder N, Shinikamin O, Shapira I, Styr B, Braun G, Harel M, Sheinin A, Geva N, Sela Y, Saito T, Saido T, Geiger T, Nir Y, Ziv Y, Slutsky I. Disrupted neural correlates of anesthesia and sleep reveal early circuit dysfunctions in Alzheimer models. Cell Rep 2022; 38:110268. [PMID: 35045289 PMCID: PMC8789564 DOI: 10.1016/j.celrep.2021.110268] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 12/06/2021] [Accepted: 12/22/2021] [Indexed: 11/30/2022] Open
Abstract
Dysregulated homeostasis of neural activity has been hypothesized to drive Alzheimer's disease (AD) pathogenesis. AD begins with a decades-long presymptomatic phase, but whether homeostatic mechanisms already begin failing during this silent phase is unknown. We show that before the onset of memory decline and sleep disturbances, familial AD (fAD) model mice display no deficits in CA1 mean firing rate (MFR) during active wakefulness. However, homeostatic down-regulation of CA1 MFR is disrupted during non-rapid eye movement (NREM) sleep and general anesthesia in fAD mouse models. The resultant hyperexcitability is attenuated by the mitochondrial dihydroorotate dehydrogenase (DHODH) enzyme inhibitor, which tunes MFR toward lower set-point values. Ex vivo fAD mutations impair downward MFR homeostasis, resulting in pathological MFR set points in response to anesthetic drug and inhibition blockade. Thus, firing rate dyshomeostasis of hippocampal circuits is masked during active wakefulness but surfaces during low-arousal brain states, representing an early failure of the silent disease stage.
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Affiliation(s)
- Daniel Zarhin
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Refaela Atsmon
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Antonella Ruggiero
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Halit Baeloha
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Shiri Shoob
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Oded Scharf
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Leore R Heim
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Nadav Buchbinder
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ortal Shinikamin
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ilana Shapira
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Boaz Styr
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Gabriella Braun
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Michal Harel
- Department of Human Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Anton Sheinin
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Nitzan Geva
- Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yaniv Sela
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama 351-0198, Japan; Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi 467-8601, Japan
| | - Takaomi Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama 351-0198, Japan
| | - Tamar Geiger
- Department of Human Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Yuval Nir
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Yaniv Ziv
- Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Inna Slutsky
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel.
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38
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Ryan TJ, Frankland PW. Forgetting as a form of adaptive engram cell plasticity. Nat Rev Neurosci 2022; 23:173-186. [PMID: 35027710 DOI: 10.1038/s41583-021-00548-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2021] [Indexed: 12/30/2022]
Abstract
One leading hypothesis suggests that memories are stored in ensembles of neurons (or 'engram cells') and that successful recall involves reactivation of these ensembles. A logical extension of this idea is that forgetting occurs when engram cells cannot be reactivated. Forms of 'natural forgetting' vary considerably in terms of their underlying mechanisms, time course and reversibility. However, we suggest that all forms of forgetting involve circuit remodelling that switches engram cells from an accessible state (where they can be reactivated by natural recall cues) to an inaccessible state (where they cannot). In many cases, forgetting rates are modulated by environmental conditions and we therefore propose that forgetting is a form of neuroplasticity that alters engram cell accessibility in a manner that is sensitive to mismatches between expectations and the environment. Moreover, we hypothesize that disease states associated with forgetting may hijack natural forgetting mechanisms, resulting in reduced engram cell accessibility and memory loss.
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Affiliation(s)
- Tomás J Ryan
- School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland. .,Trinity College Institute for Neuroscience, Trinity College Dublin, Dublin, Ireland. .,Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, Victoria, Australia. .,Child & Brain Development Program, Canadian Institute for Advanced Research (CIFAR), Toronto, Ontario, Canada.
| | - Paul W Frankland
- Child & Brain Development Program, Canadian Institute for Advanced Research (CIFAR), Toronto, Ontario, Canada. .,Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, Canada. .,Department of Psychology, University of Toronto, Toronto, Ontario, Canada. .,Department of Physiology, University of Toronto, Toronto, Ontario, Canada. .,Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada.
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39
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Wu CH, Tatavarty V, Jean Beltran PM, Guerrero AA, Keshishian H, Krug K, MacMullan MA, Li L, Carr SA, Cottrell JR, Turrigiano GG. A bidirectional switch in the Shank3 phosphorylation state biases synapses toward up- or downscaling. eLife 2022; 11:74277. [PMID: 35471151 PMCID: PMC9084893 DOI: 10.7554/elife.74277] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 04/25/2022] [Indexed: 11/13/2022] Open
Abstract
Homeostatic synaptic plasticity requires widespread remodeling of synaptic signaling and scaffolding networks, but the role of post-translational modifications in this process has not been systematically studied. Using deep-scale quantitative analysis of the phosphoproteome in mouse neocortical neurons, we found widespread and temporally complex changes during synaptic scaling up and down. We observed 424 bidirectionally modulated phosphosites that were strongly enriched for synapse-associated proteins, including S1539 in the autism spectrum disorder-associated synaptic scaffold protein Shank3. Using a parallel proteomic analysis performed on Shank3 isolated from rat neocortical neurons by immunoaffinity, we identified two sites that were persistently hypophosphorylated during scaling up and transiently hyperphosphorylated during scaling down: one (rat S1615) that corresponded to S1539 in mouse, and a second highly conserved site, rat S1586. The phosphorylation status of these sites modified the synaptic localization of Shank3 during scaling protocols, and dephosphorylation of these sites via PP2A activity was essential for the maintenance of synaptic scaling up. Finally, phosphomimetic mutations at these sites prevented scaling up but not down, while phosphodeficient mutations prevented scaling down but not up. These mutations did not impact baseline synaptic strength, indicating that they gate, rather than drive, the induction of synaptic scaling. Thus, an activity-dependent switch between hypo- and hyperphosphorylation at S1586 and S1615 of Shank3 enables scaling up or down, respectively. Collectively, our data show that activity-dependent phosphoproteome dynamics are important for the functional reconfiguration of synaptic scaffolds and can bias synapses toward upward or downward homeostatic plasticity.
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Affiliation(s)
- Chi-Hong Wu
- Department of Biology, Brandeis UniversityWalthamUnited States
| | | | | | | | - Hasmik Keshishian
- Proteomics Platform, Broad Institute of MIT and HarvardCambridgeUnited States
| | - Karsten Krug
- Proteomics Platform, Broad Institute of MIT and HarvardCambridgeUnited States
| | - Melanie A MacMullan
- Proteomics Platform, Broad Institute of MIT and HarvardCambridgeUnited States
| | - Li Li
- Stanley Center for Psychiatric Research, Broad Institute of MIT and HarvardCambridgeUnited States
| | - Steven A Carr
- Proteomics Platform, Broad Institute of MIT and HarvardCambridgeUnited States
| | - Jeffrey R Cottrell
- Stanley Center for Psychiatric Research, Broad Institute of MIT and HarvardCambridgeUnited States
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40
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Sleep promotes the formation of dendritic filopodia and spines near learning-inactive existing spines. Proc Natl Acad Sci U S A 2021; 118:2114856118. [PMID: 34873044 DOI: 10.1073/pnas.2114856118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/01/2021] [Indexed: 01/20/2023] Open
Abstract
Changes in synaptic connections are believed to underlie long-term memory storage. Previous studies have suggested that sleep is important for synapse formation after learning, but how sleep is involved in the process of synapse formation remains unclear. To address this question, we used transcranial two-photon microscopy to investigate the effect of postlearning sleep on the location of newly formed dendritic filopodia and spines of layer 5 pyramidal neurons in the primary motor cortex of adolescent mice. We found that newly formed filopodia and spines were partially clustered with existing spines along individual dendritic segments 24 h after motor training. Notably, posttraining sleep was critical for promoting the formation of dendritic filopodia and spines clustered with existing spines within 8 h. A fraction of these filopodia was converted into new spines and contributed to clustered spine formation 24 h after motor training. This sleep-dependent spine formation via filopodia was different from retraining-induced new spine formation, which emerged from dendritic shafts without prior presence of filopodia. Furthermore, sleep-dependent new filopodia and spines tended to be formed away from existing spines that were active at the time of motor training. Taken together, these findings reveal a role of postlearning sleep in regulating the number and location of new synapses via promoting filopodial formation.
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41
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Reyes-Resina I, Samer S, Kreutz MR, Oelschlegel AM. Molecular Mechanisms of Memory Consolidation That Operate During Sleep. Front Mol Neurosci 2021; 14:767384. [PMID: 34867190 PMCID: PMC8636908 DOI: 10.3389/fnmol.2021.767384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 10/27/2021] [Indexed: 11/17/2022] Open
Abstract
The role of sleep for brain function has been in the focus of interest for many years. It is now firmly established that sleep and the corresponding brain activity is of central importance for memory consolidation. Less clear are the underlying molecular mechanisms and their specific contribution to the formation of long-term memory. In this review, we summarize the current knowledge of such mechanisms and we discuss the several unknowns that hinder a deeper appreciation of how molecular mechanisms of memory consolidation during sleep impact synaptic function and engram formation.
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Affiliation(s)
- Irene Reyes-Resina
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Sebastian Samer
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Michael R Kreutz
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Leibniz Group 'Dendritic Organelles and Synaptic Function', Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Center for Behavioral Brain Sciences, Otto von Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Anja M Oelschlegel
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
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42
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Developmental Regulation of Homeostatic Plasticity in Mouse Primary Visual Cortex. J Neurosci 2021; 41:9891-9905. [PMID: 34686546 DOI: 10.1523/jneurosci.1200-21.2021] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 10/14/2021] [Accepted: 10/19/2021] [Indexed: 11/21/2022] Open
Abstract
Homeostatic plasticity maintains network stability by adjusting excitation, inhibition, or the intrinsic excitability of neurons, but the developmental regulation and coordination of these distinct forms of homeostatic plasticity remains poorly understood. A major contributor to this information gap is the lack of a uniform paradigm for chronically manipulating activity at different developmental stages. To overcome this limitation, we used designer receptors exclusively activated by designer drugs (DREADDs) to directly suppress neuronal activity in layer2/3 (L2/3) of mouse primary visual cortex of either sex at two important developmental timepoints: the classic visual system critical period [CP; postnatal day 24 (P24) to P29], and adulthood (P45 to P55). We show that 24 h of DREADD-mediated activity suppression simultaneously induces excitatory synaptic scaling up and intrinsic homeostatic plasticity in L2/3 pyramidal neurons during the CP, consistent with previous observations using prolonged visual deprivation. Importantly, manipulations known to block these forms of homeostatic plasticity when induced pharmacologically or via visual deprivation also prevented DREADD-induced homeostatic plasticity. We next used the same paradigm to suppress activity in adult animals. Surprisingly, while excitatory synaptic scaling persisted into adulthood, intrinsic homeostatic plasticity was completely absent. Finally, we found that homeostatic changes in quantal inhibitory input onto L2/3 pyramidal neurons were absent during the CP but were present in adults. Thus, the same population of neurons can express distinct sets of homeostatic plasticity mechanisms at different development stages. Our findings suggest that homeostatic forms of plasticity can be recruited in a modular manner according to the evolving needs of a developing neural circuit.SIGNIFICANCE STATEMENT Developing brain circuits are subject to dramatic changes in inputs that could destabilize activity if left uncompensated. This compensation is achieved through a set of homeostatic plasticity mechanisms that provide slow, negative feedback adjustments to excitability. Given that circuits are subject to very different destabilizing forces during distinct developmental stages, the forms of homeostatic plasticity present in the network must be tuned to these evolving needs. Here we developed a method to induce comparable homeostatic compensation during distinct developmental windows and found that neurons in the juvenile and mature brain engage strikingly different forms of homeostatic plasticity. Thus, homeostatic mechanisms can be recruited in a modular manner according to the developmental needs of the circuit.
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43
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Kaleb K, Pedrosa V, Clopath C. Network-centered homeostasis through inhibition maintains hippocampal spatial map and cortical circuit function. Cell Rep 2021; 36:109577. [PMID: 34433026 PMCID: PMC8411119 DOI: 10.1016/j.celrep.2021.109577] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 04/21/2021] [Accepted: 07/29/2021] [Indexed: 11/23/2022] Open
Abstract
Despite ongoing experiential change, neural activity maintains remarkable stability. Although this is thought to be mediated by homeostatic plasticity, what aspect of neural activity is conserved and how the flexibility necessary for learning and memory is maintained is not fully understood. Experimental studies suggest that there exists network-centered, in addition to the well-studied neuron-centered, control. Here we computationally study such a potential mechanism: input-dependent inhibitory plasticity (IDIP). In a hippocampal model, we show that IDIP can explain the emergence of active and silent place cells as well as remapping following silencing of active place cells. Furthermore, we show that IDIP can also stabilize recurrent dynamics while preserving firing rate heterogeneity and stimulus representation, as well as persistent activity after memory encoding. Hence, the establishment of global network balance with IDIP has diverse functional implications and may be able to explain experimental phenomena across different brain areas. Input-dependent inhibitory plasticity (IDIP) provides network-wide homeostasis IDIP can explain hippocampal remapping following place map silencing IDIP can also provide recurrent network homeostasis with firing rate diversity
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Affiliation(s)
- Klara Kaleb
- Bioengineering Department, Imperial College London, London, UK
| | - Victor Pedrosa
- Bioengineering Department, Imperial College London, London, UK; Sainsbury Wellcome Centre, UCL, London, UK
| | - Claudia Clopath
- Bioengineering Department, Imperial College London, London, UK.
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44
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CaMKIV Signaling Is Not Essential for the Maintenance of Intrinsic or Synaptic Properties in Mouse Visual Cortex. eNeuro 2021; 8:ENEURO.0135-21.2021. [PMID: 34001638 PMCID: PMC8260277 DOI: 10.1523/eneuro.0135-21.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/27/2021] [Accepted: 05/06/2021] [Indexed: 12/25/2022] Open
Abstract
Pyramidal neurons in rodent visual cortex homeostatically maintain their firing rates in vivo within a target range. In young cultured rat cortical neurons, Ca2+/calmodulin-dependent kinase IV (CaMKIV) signaling jointly regulates excitatory synaptic strength and intrinsic excitability to allow neurons to maintain their target firing rate. However, the role of CaMKIV signaling in regulating synaptic strength and intrinsic excitability in vivo has not been tested. Here, we show that in pyramidal neurons in visual cortex of juvenile male and female mice, CaMKIV signaling is not essential for the maintenance of basal synaptic or intrinsic properties. Neither CaMKIV conditional knock-down nor viral expression of dominant negative CaMKIV (dnCaMKIV) in vivo disrupts the intrinsic excitability or synaptic input strength of pyramidal neurons in primary visual cortex (V1), and CaMKIV signaling is not required for the increase in intrinsic excitability seen following monocular deprivation (MD). Viral expression of constitutively active CaMKIV (caCaMKIV) in vivo causes a complex disruption of the neuronal input/output function but does not affect synaptic input strength. Taken together, these results demonstrate that although augmented in vivo CaMKIV signaling can alter neuronal excitability, either endogenous CaMKIV signaling is dispensable for maintenance of excitability, or impaired CaMKIV signaling is robustly compensated.
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45
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Cary BA, Turrigiano GG. Stability of neocortical synapses across sleep and wake states during the critical period in rats. eLife 2021; 10:66304. [PMID: 34151775 PMCID: PMC8275129 DOI: 10.7554/elife.66304] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 06/20/2021] [Indexed: 12/02/2022] Open
Abstract
Sleep is important for brain plasticity, but its exact function remains mysterious. An influential but controversial idea is that a crucial function of sleep is to drive widespread downscaling of excitatory synaptic strengths. Here, we used real-time sleep classification, ex vivo measurements of postsynaptic strength, and in vivo optogenetic monitoring of thalamocortical synaptic efficacy to ask whether sleep and wake states can constitutively drive changes in synaptic strength within the neocortex of juvenile rats. We found that miniature excitatory postsynaptic current amplitudes onto L4 and L2/3 pyramidal neurons were stable across sleep- and wake-dense epochs in both primary visual (V1) and prefrontal cortex (PFC). Further, chronic monitoring of thalamocortical synaptic efficacy in V1 of freely behaving animals revealed stable responses across even prolonged periods of natural sleep and wake. Together, these data demonstrate that sleep does not drive widespread downscaling of synaptic strengths during the highly plastic critical period in juvenile animals. Whether this remarkable stability across sleep and wake generalizes to the fully mature nervous system remains to be seen.
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Affiliation(s)
- Brian A Cary
- Department of Biology, Brandeis University, Waltham, United States
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46
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Wu CH, Ramos R, Katz DB, Turrigiano GG. Homeostatic synaptic scaling establishes the specificity of an associative memory. Curr Biol 2021; 31:2274-2285.e5. [PMID: 33798429 PMCID: PMC8187282 DOI: 10.1016/j.cub.2021.03.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/01/2021] [Accepted: 03/08/2021] [Indexed: 12/21/2022]
Abstract
Correlation-based (Hebbian) forms of synaptic plasticity are crucial for the initial encoding of associative memories but likely insufficient to enable the stable storage of multiple specific memories within neural circuits. Theoretical studies have suggested that homeostatic synaptic normalization rules provide an essential countervailing force that can stabilize and expand memory storage capacity. Although such homeostatic mechanisms have been identified and studied for decades, experimental evidence that they play an important role in associative memory is lacking. Here, we show that synaptic scaling, a widely studied form of homeostatic synaptic plasticity that globally renormalizes synaptic strengths, is dispensable for initial associative memory formation but crucial for the establishment of memory specificity. We used conditioned taste aversion (CTA) learning, a form of associative learning that relies on Hebbian mechanisms within gustatory cortex (GC), to show that animals conditioned to avoid saccharin initially generalized this aversion to other novel tastants. Specificity of the aversion to saccharin emerged slowly over a time course of many hours and was associated with synaptic scaling down of excitatory synapses onto conditioning-active neuronal ensembles within gustatory cortex. Blocking synaptic scaling down in the gustatory cortex enhanced the persistence of synaptic strength increases induced by conditioning and prolonged the duration of memory generalization. Taken together, these findings demonstrate that synaptic scaling is crucial for sculpting the specificity of an associative memory and suggest that the relative strengths of Hebbian and homeostatic plasticity can modulate the balance between stable memory formation and memory generalization.
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Affiliation(s)
- Chi-Hong Wu
- Department of Biology, Brandeis University, Waltham, MA 02453, USA
| | - Raul Ramos
- Department of Biology, Brandeis University, Waltham, MA 02453, USA
| | - Donald B Katz
- Department of Psychology, Brandeis University, Waltham, MA 02453, USA
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47
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Cooper DD, Frenguelli BG. The influence of sensory experience on the glutamatergic synapse. Neuropharmacology 2021; 193:108620. [PMID: 34048870 DOI: 10.1016/j.neuropharm.2021.108620] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 05/13/2021] [Accepted: 05/17/2021] [Indexed: 12/17/2022]
Abstract
The ability of glutamatergic synaptic strength to change in response to prevailing neuronal activity is believed to underlie the capacity of animals, including humans, to learn from experience. This learning better equips animals to safely navigate challenging and potentially harmful environments, while reinforcing behaviours that are conducive to survival. Early descriptions of the influence of experience on behaviour were provided by Donald Hebb who showed that an enriched environment improved performance of rats in a variety of behavioural tasks, challenging the widely-held view at the time that psychological development and intelligence were largely predetermined through genetic inheritance. Subsequent studies in a variety of species provided detailed cellular and molecular insights into the neurobiological adaptations associated with enrichment and its counterparts, isolation and deprivation. Here we review those experience-dependent changes that occur at the glutamatergic synapse, and which likely underlie the enhanced cognition associated with enrichment. We focus on the importance of signalling initiated by the release of BDNF and a prime downstream effector, MSK1, in orchestrating the many structural and functional neuronal adaptations associated with enrichment. In particular we discuss the MSK1-dependent expansion of the dynamic range of the glutamatergic synapse, which may allow enhanced information storage or processing, and the establishment of a genomic homeostasis that may both stabilise the enriched brain, and may make it better able to respond to novel experiences.
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Affiliation(s)
- Daniel D Cooper
- School of Life Sciences, University of Warwick, Coventry, UK
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48
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Ruggiero A, Katsenelson M, Slutsky I. Mitochondria: new players in homeostatic regulation of firing rate set points. Trends Neurosci 2021; 44:605-618. [PMID: 33865626 DOI: 10.1016/j.tins.2021.03.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 02/10/2021] [Accepted: 03/11/2021] [Indexed: 10/21/2022]
Abstract
Neural circuit functions are stabilized by homeostatic processes at long timescales in response to changes in behavioral states, experience, and learning. However, it remains unclear which specific physiological variables are being stabilized and which cellular or neural network components compose the homeostatic machinery. At this point, most evidence suggests that the distribution of firing rates among neurons in a neuronal circuit is the key variable that is maintained around a set-point value in a process called 'firing rate homeostasis.' Here, we review recent findings that implicate mitochondria as central players in mediating firing rate homeostasis. While mitochondria are known to regulate neuronal variables such as synaptic vesicle release or intracellular calcium concentration, the mitochondrial signaling pathways that are essential for firing rate homeostasis remain largely unknown. We used basic concepts of control theory to build a framework for classifying possible components of the homeostatic machinery that stabilizes firing rate, and we particularly emphasize the potential role of sleep and wakefulness in this homeostatic process. This framework may facilitate the identification of new homeostatic pathways whose malfunctions drive instability of neural circuits in distinct brain disorders.
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Affiliation(s)
- Antonella Ruggiero
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Maxim Katsenelson
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel; Sagol School of Neuroscience, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Inna Slutsky
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel; Sagol School of Neuroscience, Tel Aviv University, 69978 Tel Aviv, Israel.
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49
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Sleep calms firing rates. Nat Rev Neurosci 2021; 22:74-75. [PMID: 33293691 DOI: 10.1038/s41583-020-00419-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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50
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Trojanowski NF, Bottorff J, Turrigiano GG. Activity labeling in vivo using CaMPARI2 reveals intrinsic and synaptic differences between neurons with high and low firing rate set points. Neuron 2021; 109:663-676.e5. [PMID: 33333001 PMCID: PMC7897300 DOI: 10.1016/j.neuron.2020.11.027] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 10/27/2020] [Accepted: 11/24/2020] [Indexed: 11/25/2022]
Abstract
Neocortical pyramidal neurons regulate firing around a stable mean firing rate (FR) that can differ by orders of magnitude between neurons, but the factors that determine where individual neurons sit within this broad FR distribution are not understood. To access low- and high-FR neurons for ex vivo analysis, we used Ca2+- and UV-dependent photoconversion of CaMPARI2 in vivo to permanently label neurons according to mean FR. CaMPARI2 photoconversion was correlated with immediate early gene expression and higher FRs ex vivo and tracked the drop and rebound in ensemble mean FR induced by prolonged monocular deprivation. High-activity L4 pyramidal neurons had greater intrinsic excitability and recurrent excitatory synaptic strength, while E/I ratio, local output strength, and local connection probability were not different. Thus, in L4 pyramidal neurons (considered a single transcriptional cell type), a broad mean FR distribution is achieved through graded differences in both intrinsic and synaptic properties.
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Affiliation(s)
| | - Juliet Bottorff
- Department of Biology, Brandeis University, Waltham, MA 02453, USA
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