1
|
Birch EE, Duffy KR. Leveraging neural plasticity for the treatment of amblyopia. Surv Ophthalmol 2024:S0039-6257(24)00046-8. [PMID: 38763223 DOI: 10.1016/j.survophthal.2024.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 04/27/2024] [Accepted: 04/29/2024] [Indexed: 05/21/2024]
Abstract
Amblyopia is a form of visual cortical impairment that arises from abnormal visual experience early in life. Most often, amblyopia is a unilateral visual impairment that can develop as a result of strabismus, anisometropia, or a combination of these conditions that result in discordant binocular experience. Characterized by reduced visual acuity and impaired binocular function, amblyopia places a substantial burden on the developing child. Although frontline treatment with glasses and patching can improve visual acuity, residual amblyopia remains for most children. Newer binocular-based therapies can elicit rapid recovery of visual acuity and may also improve stereoacuity in some children. Nevertheless, for both treatment modalities full recovery is elusive, recurrence of amblyopia is common, and improvements are negligible when treatment is administered at older ages. Insights derived from animal models about the factors that govern neural plasticity have been leveraged to develop innovative treatments for amblyopia. These novel therapies exhibit efficacy to promote recovery, and some are effective even at ages when conventional treatments fail to yield benefit. Approaches for enhancing visual system plasticity and promoting recovery from amblyopia include altering the balance between excitatory and inhibitory mechanisms, reversing the accumulation of proteins that inhibit plasticity, and harnessing the principles of metaplasticity. Although these therapies have exhibited promising results in animal models, their safety and ability to remediate amblyopia need to be evaluated in humans.
Collapse
Affiliation(s)
- Eileen E Birch
- Crystal Charity Ball Pediatric Vision Laboratory, Retina Foundation, Dallas, TX, USA; University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Kevin R Duffy
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, NS, Canada
| |
Collapse
|
2
|
Paveliev M, Egorchev AA, Musin F, Lipachev N, Melnikova A, Gimadutdinov RM, Kashipov AR, Molotkov D, Chickrin DE, Aganov AV. Perineuronal Net Microscopy: From Brain Pathology to Artificial Intelligence. Int J Mol Sci 2024; 25:4227. [PMID: 38673819 PMCID: PMC11049984 DOI: 10.3390/ijms25084227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/31/2024] [Accepted: 04/05/2024] [Indexed: 04/28/2024] Open
Abstract
Perineuronal nets (PNN) are a special highly structured type of extracellular matrix encapsulating synapses on large populations of CNS neurons. PNN undergo structural changes in schizophrenia, epilepsy, Alzheimer's disease, stroke, post-traumatic conditions, and some other brain disorders. The functional role of the PNN microstructure in brain pathologies has remained largely unstudied until recently. Here, we review recent research implicating PNN microstructural changes in schizophrenia and other disorders. We further concentrate on high-resolution studies of the PNN mesh units surrounding synaptic boutons to elucidate fine structural details behind the mutual functional regulation between the ECM and the synaptic terminal. We also review some updates regarding PNN as a potential pharmacological target. Artificial intelligence (AI)-based methods are now arriving as a new tool that may have the potential to grasp the brain's complexity through a wide range of organization levels-from synaptic molecular events to large scale tissue rearrangements and the whole-brain connectome function. This scope matches exactly the complex role of PNN in brain physiology and pathology processes, and the first AI-assisted PNN microscopy studies have been reported. To that end, we report here on a machine learning-assisted tool for PNN mesh contour tracing.
Collapse
Affiliation(s)
- Mikhail Paveliev
- Neuroscience Center, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland
| | - Anton A. Egorchev
- Institute of Computational Mathematics and Information Technologies, Kazan Federal University, Kremlyovskaya 35, Kazan 420008, Tatarstan, Russia; (A.A.E.); (F.M.); (R.M.G.)
| | - Foat Musin
- Institute of Computational Mathematics and Information Technologies, Kazan Federal University, Kremlyovskaya 35, Kazan 420008, Tatarstan, Russia; (A.A.E.); (F.M.); (R.M.G.)
| | - Nikita Lipachev
- Institute of Physics, Kazan Federal University, Kremlyovskaya 16a, Kazan 420008, Tatarstan, Russia; (N.L.); (A.V.A.)
| | - Anastasiia Melnikova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Karl Marx 74, Kazan 420015, Tatarstan, Russia;
| | - Rustem M. Gimadutdinov
- Institute of Computational Mathematics and Information Technologies, Kazan Federal University, Kremlyovskaya 35, Kazan 420008, Tatarstan, Russia; (A.A.E.); (F.M.); (R.M.G.)
| | - Aidar R. Kashipov
- Institute of Artificial Intelligence, Robotics and Systems Engineering, Kazan Federal University, Kremlyovskaya 18, Kazan 420008, Tatarstan, Russia; (A.R.K.); (D.E.C.)
| | - Dmitry Molotkov
- Biomedicum Imaging Unit, University of Helsinki, Haartmaninkatu 8, 00014 Helsinki, Finland;
| | - Dmitry E. Chickrin
- Institute of Artificial Intelligence, Robotics and Systems Engineering, Kazan Federal University, Kremlyovskaya 18, Kazan 420008, Tatarstan, Russia; (A.R.K.); (D.E.C.)
| | - Albert V. Aganov
- Institute of Physics, Kazan Federal University, Kremlyovskaya 16a, Kazan 420008, Tatarstan, Russia; (N.L.); (A.V.A.)
| |
Collapse
|
3
|
Valerio P, Rechenmann J, Joshi S, De Franceschi G, Barkat TR. Sequential maturation of stimulus-specific adaptation in the mouse lemniscal auditory system. SCIENCE ADVANCES 2024; 10:eadi7624. [PMID: 38170771 PMCID: PMC10776000 DOI: 10.1126/sciadv.adi7624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 12/01/2023] [Indexed: 01/05/2024]
Abstract
Stimulus-specific adaptation (SSA), the reduction of neural activity to a common stimulus that does not generalize to other, rare stimuli, is an essential property of our brain. Although well characterized in adults, it is still unknown how it develops during adolescence and what neuronal circuits are involved. Using in vivo electrophysiology and optogenetics in the lemniscal pathway of the mouse auditory system, we observed SSA to be stable from postnatal day 20 (P20) in the inferior colliculus, to develop until P30 in the auditory thalamus and even later in the primary auditory cortex (A1). We found this maturation process to be experience-dependent in A1 but not in thalamus and to be related to alterations in deep but not input layers of A1. We also identified corticothalamic projections to be implicated in thalamic SSA development. Together, our results reveal different circuits underlying the sequential SSA maturation and provide a unique perspective to understand predictive coding and surprise across sensory systems.
Collapse
Affiliation(s)
- Patricia Valerio
- Department of Biomedicine, Basel University, 4056 Basel, Switzerland
| | - Julien Rechenmann
- Department of Biomedicine, Basel University, 4056 Basel, Switzerland
| | - Suyash Joshi
- Department of Biomedicine, Basel University, 4056 Basel, Switzerland
| | | | | |
Collapse
|
4
|
Duffy KR, Bear MF, Patel NB, Das VE, Tychsen L. Human deprivation amblyopia: treatment insights from animal models. Front Neurosci 2023; 17:1249466. [PMID: 37795183 PMCID: PMC10545969 DOI: 10.3389/fnins.2023.1249466] [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: 06/28/2023] [Accepted: 09/04/2023] [Indexed: 10/06/2023] Open
Abstract
Amblyopia is a common visual impairment that develops during the early years of postnatal life. It emerges as a sequela to eye misalignment, an imbalanced refractive state, or obstruction to form vision. All of these conditions prevent normal vision and derail the typical development of neural connections within the visual system. Among the subtypes of amblyopia, the most debilitating and recalcitrant to treatment is deprivation amblyopia. Nevertheless, human studies focused on advancing the standard of care for amblyopia have largely avoided recruitment of patients with this rare but severe impairment subtype. In this review, we delineate characteristics of deprivation amblyopia and underscore the critical need for new and more effective therapy. Animal models offer a unique opportunity to address this unmet need by enabling the development of unconventional and potent amblyopia therapies that cannot be pioneered in humans. Insights derived from studies using animal models are discussed as potential therapeutic innovations for the remediation of deprivation amblyopia. Retinal inactivation is highlighted as an emerging therapy that exhibits efficacy against the effects of monocular deprivation at ages when conventional therapy is ineffective, and recovery occurs without apparent detriment to the treated eye.
Collapse
Affiliation(s)
- Kevin R. Duffy
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, NS, Canada
| | - Mark F. Bear
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Nimesh B. Patel
- College of Optometry, University of Houston, Houston, TX, United States
| | - Vallabh E. Das
- College of Optometry, University of Houston, Houston, TX, United States
| | - Lawrence Tychsen
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, United States
| |
Collapse
|
5
|
Min SH, Wang Z, Chen MT, Hu R, Gong L, He Z, Wang X, Hess RF, Zhou J. Metaplasticity: Dark exposure boosts local excitability and visual plasticity in adult human cortex. J Physiol 2023; 601:4105-4120. [PMID: 37573529 DOI: 10.1113/jp284040] [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: 02/23/2023] [Accepted: 07/25/2023] [Indexed: 08/15/2023] Open
Abstract
An interlude of dark exposure for about 1 week is known to shift excitatory/inhibitory (E/I) balance of the mammalian visual cortex, promoting plasticity and accelerating visual recovery in animals that have experienced cortical lesions during development. However, the translational impact of our understanding of dark exposure from animal studies to humans remains elusive. Here, we used magnetic resonance spectroscopy as a probe for E/I balance in the primary visual cortex (V1) to determine the effect of 60 min of dark exposure, and measured binocular combination as a behavioural assay to assess visual plasticity in 14 normally sighted human adults. To induce neuroplastic changes in the observers, we introduced 60 min of monocular deprivation, which is known to temporarily shift sensory eye balance in favour of the previously deprived eye. We report that prior dark exposure for 60 min strengthens local excitability in V1 and boosts visual plasticity in normal adults. However, we show that it does not promote plasticity in amblyopic adults. Nevertheless, our findings are surprising, given the fact that the interlude is very brief. Interestingly, we find that the increased concentration of the excitatory neurotransmitter is not strongly correlated with the enhanced functional plasticity. Instead, the absolute degree of change in its concentration is related to the boost, suggesting that the dichotomy of cortical excitation and inhibition might not explain the physiological basis of plasticity in humans. We present the first evidence that an environmental manipulation that shifts cortical E/I balance can also act as a metaplastic facilitator for visual plasticity in humans. KEY POINTS: A brief interlude (60 min) of dark exposure increased the local concentration of glutamine/glutamate but not that of GABA in the visual cortex of adult humans. After dark exposure, the degree of the shift in sensory eye dominance in favour of the previously deprived eye from short-term monocular deprivation was larger than that from only monocular deprivation. The neurochemical and behavioural measures were associated: the magnitude of the shift in the concentration of glutamine/glutamate was correlated with the boost in perceptual plasticity after dark exposure. Surprisingly, the increase in the concentration of glutamine/glutamate was not correlated with the perceptual boost after dark exposure, suggesting that the physiological mechanism of how E/I balance regulates plasticity is not deterministic. In other words, an increased excitation did not unilaterally promote plasticity.
Collapse
Affiliation(s)
- Seung Hyun Min
- School of Ophthalmology & Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Zili Wang
- School of Ophthalmology & Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Meng Ting Chen
- School of Ophthalmology & Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Rongjie Hu
- Center for Biomedical Imaging, University of Science and Technology of China, Anhui, China
| | - Ling Gong
- School of Ophthalmology & Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Zhifen He
- School of Ophthalmology & Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Xiaoxiao Wang
- Center for Biomedical Imaging, University of Science and Technology of China, Anhui, China
| | - Robert F Hess
- McGill Vision Research, Department of Ophthalmology and Visual Sciences, McGill University, Montreal, Canada
| | - Jiawei Zhou
- School of Ophthalmology & Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| |
Collapse
|
6
|
Zheng J, Zhang W, Liu L, Hung Yap MK. Low frequency repetitive transcranial magnetic stimulation promotes plasticity of the visual cortex in adult amblyopic rats. Front Neurosci 2023; 17:1109735. [PMID: 36743805 PMCID: PMC9892759 DOI: 10.3389/fnins.2023.1109735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 01/02/2023] [Indexed: 01/20/2023] Open
Abstract
The decline of visual plasticity restricts the recovery of visual functions in adult amblyopia. Repetitive transcranial magnetic stimulation (rTMS) has been shown to be effective in treating adult amblyopia. However, the underlying mechanisms of rTMS on visual cortex plasticity remain unclear. In this study, we found that low-frequency rTMS reinstated the amplitude of visual evoked potentials, but did not influence the impaired depth perception of amblyopic rats. Furthermore, the expression of synaptic plasticity genes and the number of dendritic spines were significantly higher in amblyopic rats which received rTMS when compared with amblyopic rats which received sham stimulation, with reduced level of inhibition and perineuronal nets in visual cortex, as observed via molecular and histological investigations. The results provide further evidence that rTMS enhances functional recovery and visual plasticity in an adult amblyopic animal model.
Collapse
Affiliation(s)
- Jing Zheng
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China,Department of Optometry and Visual Science, West China Hospital, Sichuan University, Chengdu, China
| | - Wenqiu Zhang
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China,Department of Optometry and Visual Science, West China Hospital, Sichuan University, Chengdu, China,*Correspondence: Wenqiu Zhang,
| | - Longqian Liu
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China,Department of Optometry and Visual Science, West China Hospital, Sichuan University, Chengdu, China
| | | |
Collapse
|
7
|
Jeon BB, Fuchs T, Chase SM, Kuhlman SJ. Visual experience has opposing influences on the quality of stimulus representation in adult primary visual cortex. eLife 2022; 11:80361. [PMID: 36321876 PMCID: PMC9629826 DOI: 10.7554/elife.80361] [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] [Accepted: 10/21/2022] [Indexed: 11/07/2022] Open
Abstract
Transient dark exposure, typically 7–10 days in duration, followed by light reintroduction is an emerging treatment for improving the restoration of vision in amblyopic subjects whose occlusion is removed in adulthood. Dark exposure initiates homeostatic mechanisms that together with light-induced changes in cellular signaling pathways result in the re-engagement of juvenile-like plasticity in the adult such that previously deprived inputs can gain cortical territory. It is possible that dark exposure itself degrades visual responses, and this could place constraints on the optimal duration of dark exposure treatment. To determine whether eight days of dark exposure has a lasting negative impact on responses to classic grating stimuli, neural activity was recorded before and after dark exposure in awake head-fixed mice using two-photon calcium imaging. Neural discriminability, assessed using classifiers, was transiently reduced following dark exposure; a decrease in response reliability across a broad range of spatial frequencies likely contributed to the disruption. Both discriminability and reliability recovered. Fixed classifiers were used to demonstrate that stimulus representation rebounded to the original, pre-deprivation state, thus dark exposure did not appear to have a lasting negative impact on visual processing. Unexpectedly, we found that dark exposure significantly stabilized orientation preference and signal correlation. Our results reveal that natural vision exerts a disrupting influence on the stability of stimulus preference for classic grating stimuli and, at the same time, improves neural discriminability for both low and high-spatial frequency stimuli.
Collapse
Affiliation(s)
- Brian B Jeon
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, United States.,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, United States.,Neuroscience Institute, Carnegie Mellon University, Pittsburgh, United States
| | - Thomas Fuchs
- Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, United States.,Neuroscience Institute, Carnegie Mellon University, Pittsburgh, United States.,Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, United States
| | - Steven M Chase
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, United States.,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, United States.,Neuroscience Institute, Carnegie Mellon University, Pittsburgh, United States
| | - Sandra J Kuhlman
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, United States.,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, United States.,Neuroscience Institute, Carnegie Mellon University, Pittsburgh, United States.,Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, United States
| |
Collapse
|
8
|
Barkus C, Bergmann C, Branco T, Carandini M, Chadderton PT, Galiñanes GL, Gilmour G, Huber D, Huxter JR, Khan AG, King AJ, Maravall M, O'Mahony T, Ragan CI, Robinson ESJ, Schaefer AT, Schultz SR, Sengpiel F, Prescott MJ. Refinements to rodent head fixation and fluid/food control for neuroscience. J Neurosci Methods 2022; 381:109705. [PMID: 36096238 DOI: 10.1016/j.jneumeth.2022.109705] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 09/01/2022] [Accepted: 09/03/2022] [Indexed: 12/14/2022]
Abstract
The use of head fixation in mice is increasingly common in research, its use having initially been restricted to the field of sensory neuroscience. Head restraint has often been combined with fluid control, rather than food restriction, to motivate behaviour, but this too is now in use for both restrained and non-restrained animals. Despite this, there is little guidance on how best to employ these techniques to optimise both scientific outcomes and animal welfare. This article summarises current practices and provides recommendations to improve animal wellbeing and data quality, based on a survey of the community, literature reviews, and the expert opinion and practical experience of an international working group convened by the UK's National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs). Topics covered include head fixation surgery and post-operative care, habituation to restraint, and the use of fluid/food control to motivate performance. We also discuss some recent developments that may offer alternative ways to collect data from large numbers of behavioural trials without the need for restraint. The aim is to provide support for researchers at all levels, animal care staff, and ethics committees to refine procedures and practices in line with the refinement principle of the 3Rs.
Collapse
Affiliation(s)
- Chris Barkus
- National Centre for Replacement, Refinement and Reduction of Animals in Research (NC3Rs), London, UK.
| | | | - Tiago Branco
- Sainsbury Wellcome Centre, University College London, London, UK
| | - Matteo Carandini
- Institute of Ophthalmology, University College London, London, UK
| | - Paul T Chadderton
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | | | | | - Daniel Huber
- Department of Basic Neurosciences, University of Geneva, Geneva, Switzerland
| | | | - Adil G Khan
- Centre for Developmental Neurobiology, King's College London, London, UK
| | - Andrew J King
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Miguel Maravall
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, UK
| | - Tina O'Mahony
- Sainsbury Wellcome Centre, University College London, London, UK
| | - C Ian Ragan
- National Centre for Replacement, Refinement and Reduction of Animals in Research (NC3Rs), London, UK
| | - Emma S J Robinson
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Andreas T Schaefer
- Sensory Circuits and Neurotechnology Laboratory, The Francis Crick Institute, London, UK; Department of Neuroscience, Physiology & Pharmacology, University College London, London, UK
| | - Simon R Schultz
- Centre for Neurotechnology and Department of Bioengineering, Imperial College London, London, UK
| | | | - Mark J Prescott
- National Centre for Replacement, Refinement and Reduction of Animals in Research (NC3Rs), London, UK
| |
Collapse
|
9
|
Hao X, Liu Q, Chan J, Li N, Shi X, Gu Y. Dark exposure can partly restore the disrupted cortical reliability Binocular visual experience drives the maturation of response variability and reliability in the visual cortex. iScience 2022; 25:104984. [PMID: 36105593 PMCID: PMC9465340 DOI: 10.1016/j.isci.2022.104984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 06/23/2022] [Accepted: 08/16/2022] [Indexed: 10/25/2022] Open
|
10
|
Abstract
For four decades, investigations of the biological basis of critical periods in the developing mammalian visual cortex were dominated by study of the consequences of altered early visual experience in cats and nonhuman primates. The neural deficits thus revealed also provided insight into the origin and neural basis of human amblyopia that in turn motivated additional studies of humans with abnormal early visual input. Recent human studies point to deficits arising from alterations in all visual cortical areas and even in nonvisual cortical regions. As the new human data accumulated in parallel with a near-complete shift toward the use of rodent animal models for the study of neural mechanisms, it is now essential to review the human data and the earlier animal data obtained from cats and monkeys to infer general conclusions and to optimize future choice of the most appropriate animal model. Expected final online publication date for the Annual Review of Vision Science, Volume 8 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- Donald E Mitchell
- Department of Psychology & Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada;
| | - Daphne Maurer
- Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, Ontario, Canada;
| |
Collapse
|
11
|
Pietra G, Bonifacino T, Talamonti D, Bonanno G, Sale A, Galli L, Baroncelli L. Visual Cortex Engagement in Retinitis Pigmentosa. Int J Mol Sci 2021; 22:ijms22179412. [PMID: 34502320 PMCID: PMC8431500 DOI: 10.3390/ijms22179412] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/20/2021] [Accepted: 08/26/2021] [Indexed: 11/24/2022] Open
Abstract
Retinitis pigmentosa (RP) is a family of inherited disorders caused by the progressive degeneration of retinal photoreceptors. There is no cure for RP, but recent research advances have provided promising results from many clinical trials. All these therapeutic strategies are focused on preserving existing photoreceptors or substituting light-responsive elements. Vision recovery, however, strongly relies on the anatomical and functional integrity of the visual system beyond photoreceptors. Although the retinal structure and optic pathway are substantially preserved at least in early stages of RP, studies describing the visual cortex status are missing. Using a well-established mouse model of RP, we analyzed the response of visual cortical circuits to the progressive degeneration of photoreceptors. We demonstrated that the visual cortex goes through a transient and previously undescribed alteration in the local excitation/inhibition balance, with a net shift towards increased intracortical inhibition leading to improved filtering and decoding of corrupted visual inputs. These results suggest a compensatory action of the visual cortex that increases the range of residual visual sensitivity in RP.
Collapse
Affiliation(s)
- Gianluca Pietra
- Neuroscience Institute, National Research Council (CNR), I-56124 Pisa, Italy; (G.P.); (D.T.); (A.S.); (L.G.)
| | - Tiziana Bonifacino
- Section of Pharmacology and Toxicology Unit, Department of Pharmacy, University of Genova, I-16148 Genova, Italy; (T.B.); (G.B.)
| | - Davide Talamonti
- Neuroscience Institute, National Research Council (CNR), I-56124 Pisa, Italy; (G.P.); (D.T.); (A.S.); (L.G.)
- Department of Life Science, University of Trieste, I-34128 Trieste, Italy
| | - Giambattista Bonanno
- Section of Pharmacology and Toxicology Unit, Department of Pharmacy, University of Genova, I-16148 Genova, Italy; (T.B.); (G.B.)
- IRCCS Ospedale Policlinico San Martino, I-16132 Genova, Italy
| | - Alessandro Sale
- Neuroscience Institute, National Research Council (CNR), I-56124 Pisa, Italy; (G.P.); (D.T.); (A.S.); (L.G.)
| | - Lucia Galli
- Neuroscience Institute, National Research Council (CNR), I-56124 Pisa, Italy; (G.P.); (D.T.); (A.S.); (L.G.)
| | - Laura Baroncelli
- Neuroscience Institute, National Research Council (CNR), I-56124 Pisa, Italy; (G.P.); (D.T.); (A.S.); (L.G.)
- Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, I-56128 Pisa, Italy
- Correspondence: ; Tel.: +39-503-153199; Fax: +39-503-153220
| |
Collapse
|
12
|
Aronitz EM, Kamermans BA, Duffy KR. Development of parvalbumin neurons and perineuronal nets in the visual cortex of normal and dark-exposed cats. J Comp Neurol 2021; 529:2827-2841. [PMID: 33576496 DOI: 10.1002/cne.25127] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 02/07/2021] [Accepted: 02/08/2021] [Indexed: 11/06/2022]
Abstract
During development, the visual system maintains a high capacity for modification by expressing characteristics permissive for plasticity, enabling neural circuits to be refined by visual experience to achieve their mature form. This period is followed by the emergence of characteristics that stabilize the brain to consolidate for lifetime connections that were informed by experience. Attenuation of plasticity potential is thought to derive from an accumulation of plasticity-inhibiting characteristics that appear at ages beyond the peak of plasticity. Perineuronal nets (PNNs) are molecular aggregations that primarily surround fast-spiking inhibitory neurons called parvalbumin (PV) cells, which exhibit properties congruent with a plasticity inhibitor. In this study, we examined the development of PNNs and PV cells in the primary visual cortex of a highly visual mammal, and assessed the impact that 10 days of darkness had on both characteristics. Here, we show that labeling for PV expression emerges earlier and reaches adult levels sooner than PNNs. We also demonstrate that darkness, a condition known to enhance plasticity, significantly reduces the density of PNNs and the size of PV cell somata but does not alter the number of PV cells in the visual cortex. The darkness-induced reduction of PV cell size occurred irrespective of whether neurons were surrounded by a PNN, suggesting that PNNs have a restricted capacity to inhibit plasticity. Finally, we show that PV cells surrounded by a PNN were significantly larger than those without one, supporting the view that PNNs may mediate trophic support to the cells they surround.
Collapse
Affiliation(s)
- Elise M Aronitz
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Braden A Kamermans
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Kevin R Duffy
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada
| |
Collapse
|
13
|
Ribot J, Breton R, Calvo CF, Moulard J, Ezan P, Zapata J, Samama K, Moreau M, Bemelmans AP, Sabatet V, Dingli F, Loew D, Milleret C, Billuart P, Dallérac G, Rouach N. Astrocytes close the mouse critical period for visual plasticity. Science 2021; 373:77-81. [PMID: 34210880 DOI: 10.1126/science.abf5273] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 05/13/2021] [Indexed: 12/26/2022]
Abstract
Brain postnatal development is characterized by critical periods of experience-dependent remodeling of neuronal circuits. Failure to end these periods results in neurodevelopmental disorders. The cellular processes defining critical-period timing remain unclear. Here, we show that in the mouse visual cortex, astrocytes control critical-period closure. We uncover the underlying pathway, which involves astrocytic regulation of the extracellular matrix, allowing interneuron maturation. Unconventional astrocyte connexin signaling hinders expression of extracellular matrix-degrading enzyme matrix metalloproteinase 9 (MMP9) through RhoA-guanosine triphosphatase activation. Thus, astrocytes not only influence the activity of single synapses but also are key elements in the experience-dependent wiring of brain circuits.
Collapse
Affiliation(s)
- Jérôme Ribot
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France
| | - Rachel Breton
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France.,Doctoral School N°568, Paris Saclay University, PSL Research University, Le Kremlin Bicetre, France.,Université Paris-Saclay, CNRS, Institut des neurosciences Paris-Saclay, Gif-sur-Yvette, France
| | - Charles-Félix Calvo
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France
| | - Julien Moulard
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France.,Doctoral School N°158, Sorbonne University, Paris, France
| | - Pascal Ezan
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France
| | - Jonathan Zapata
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France
| | - Kevin Samama
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France
| | - Matthieu Moreau
- Université de Paris, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Genetic and Development of Cerebral Cortex Laboratory, GHU Paris Psychiatrie et Neurosciences, Hôpital Saint Anne, Paris, France
| | - Alexis-Pierre Bemelmans
- Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Département de la Recherche Fondamentale, Institut de biologie François Jacob, MIRCen, and CNRS UMR 9199, Université Paris-Saclay, Neurodegenerative Diseases Laboratory, Fontenay-aux-Roses, France
| | - Valentin Sabatet
- Institut Curie, PSL Research University, Mass Spectrometry and Proteomics Laboratory, Paris, France
| | - Florent Dingli
- Institut Curie, PSL Research University, Mass Spectrometry and Proteomics Laboratory, Paris, France
| | - Damarys Loew
- Institut Curie, PSL Research University, Mass Spectrometry and Proteomics Laboratory, Paris, France
| | - Chantal Milleret
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France
| | - Pierre Billuart
- Université de Paris, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Genetic and Development of Cerebral Cortex Laboratory, GHU Paris Psychiatrie et Neurosciences, Hôpital Saint Anne, Paris, France
| | - Glenn Dallérac
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France
| | - Nathalie Rouach
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France.
| |
Collapse
|
14
|
Gotou T, Kameyama K, Kobayashi A, Okamura K, Ando T, Terata K, Yamada C, Ohta H, Morizane A, Hata Y. Dark Rearing Promotes the Recovery of Visual Cortical Responses but Not the Morphology of Geniculocortical Axons in Amblyopic Cat. Front Neural Circuits 2021; 15:637638. [PMID: 33935657 PMCID: PMC8085520 DOI: 10.3389/fncir.2021.637638] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 03/23/2021] [Indexed: 11/13/2022] Open
Abstract
Monocular deprivation (MD) of vision during early postnatal life induces amblyopia, and most neurons in the primary visual cortex lose their responses to the closed eye. Anatomically, the somata of neurons in the closed-eye recipient layer of the lateral geniculate nucleus (LGN) shrink and their axons projecting to the visual cortex retract. Although it has been difficult to restore visual acuity after maturation, recent studies in rodents and cats showed that a period of exposure to complete darkness could promote recovery from amblyopia induced by prior MD. However, in cats, which have an organization of central visual pathways similar to humans, the effect of dark rearing only improves monocular vision and does not restore binocular depth perception. To determine whether dark rearing can completely restore the visual pathway, we examined its effect on the three major concomitants of MD in individual visual neurons, eye preference of visual cortical neurons and soma size and axon morphology of LGN neurons. Dark rearing improved the recovery of visual cortical responses to the closed eye compared with the recovery under binocular conditions. However, geniculocortical axons serving the closed eye remained retracted after dark rearing, whereas reopening the closed eye restored the soma size of LGN neurons. These results indicate that dark rearing incompletely restores the visual pathway, and thus exerts a limited restorative effect on visual function.
Collapse
Affiliation(s)
- Takahiro Gotou
- Division of Integrative Bioscience, Tottori University Graduate School of Medical Sciences, Yonago, Japan
| | - Katsuro Kameyama
- Division of Integrative Bioscience, Tottori University Graduate School of Medical Sciences, Yonago, Japan.,Division of Neuroscience, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Ayane Kobayashi
- Division of Integrative Bioscience, Tottori University Graduate School of Medical Sciences, Yonago, Japan
| | - Kayoko Okamura
- Division of Integrative Bioscience, Tottori University Graduate School of Medical Sciences, Yonago, Japan
| | - Takahiko Ando
- Division of Neuroscience, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Keiko Terata
- Division of Integrative Bioscience, Tottori University Graduate School of Medical Sciences, Yonago, Japan
| | - Chihiro Yamada
- Division of Integrative Bioscience, Tottori University Graduate School of Medical Sciences, Yonago, Japan
| | - Hiroyuki Ohta
- Division of Integrative Bioscience, Tottori University Graduate School of Medical Sciences, Yonago, Japan
| | - Ayaka Morizane
- Division of Neuroscience, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Yoshio Hata
- Division of Integrative Bioscience, Tottori University Graduate School of Medical Sciences, Yonago, Japan.,Division of Neuroscience, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Japan
| |
Collapse
|
15
|
Charles James J, Funke K. Repetitive transcranial magnetic stimulation reverses reduced excitability of rat visual cortex induced by dark rearing during early critical period. Dev Neurobiol 2020; 80:399-410. [PMID: 33006265 DOI: 10.1002/dneu.22785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/14/2020] [Accepted: 09/24/2020] [Indexed: 01/20/2023]
Abstract
Early critical period of visual cortex is characterized by enhanced activity-driven neuronal plasticity establishing the specificity of neuronal connections required for optimal processing of sensory signals. Deprivation from visual input by dark rearing (DR) during this period leads to a lasting impairment of visual performance. Previously, we demonstrated that repetitive transcranial magnetic stimulation (rTMS) applied with intermittent theta-burst (iTBS) pattern during the critical period improved the visual performance of the DR rats. In this study, we describe that the excitability of the binocular part of the visual cortex (V1b), as measured in acute brain slices by input-output ratios of field excitatory synaptic potentials (fEPSPs), is lowered in DR rats compared to normal controls. Verum rTMS applied with the iTBS pattern during DR reversed this DR effect, while no rTMS effect was evident in the non-DR (nDR) rats. In addition, verum rTMS reduced the number of neurons expressing the 67 kD isoform of glutamic acid decarboxylase (GAD67), the calcium-binding protein calbindin (CB) and the zinc-finger transcription factor zif268/EGR1, as determined via immunohistochemistry, only in DR rats but not in nDR rats. Moreover, rTMS reduced the number of neurons expressing the calcium-binding protein parvalbumin (PV) only in nDR rats which showed more PV+ neurons compared to DR rats. This study confirms that iTBS-rTMS may be able to prevent or reverse the effects of DR on visual cortex physiology, likely through a modulation of the activity of inhibitory interneurons.
Collapse
Affiliation(s)
| | - Klaus Funke
- Department of Neurophysiology, Medical Faculty, Ruhr-University Bochum, Bochum, Germany
| |
Collapse
|
16
|
Zhang Y, Fu T, Han S, Ding Y, Wang J, Zheng J, Li J. Monocular Deprivation Affects Visual Cortex Plasticity Through cPKCγ-Modulated GluR1 Phosphorylation in Mice. Invest Ophthalmol Vis Sci 2020; 61:44. [PMID: 32343785 PMCID: PMC7401946 DOI: 10.1167/iovs.61.4.44] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Purpose To determine how visual cortex plasticity changes after monocular deprivation (MD) in mice and whether conventional protein kinase C gamma (cPKCγ) plays a role in visual cortex plasticity. Methods cPKCγ membrane translocation levels were quantified by using immunoblotting to explore the effects of MD on cPKCγ activation. Electrophysiology was used to record field excitatory postsynaptic potential (fEPSP) amplitude with the goal of observing changes in visual cortex plasticity after MD. Immunoblotting was also used to determine the phosphorylation levels of GluR1 at Ser831. Light transmission was analyzed using electroretinography to examine the effects of MD and cPKCγ on mouse retinal function. Results Membrane translocation levels of cPKCγ significantly increased in the contralateral visual cortex of MD mice compared to wild-type (WT) mice (P < 0.001). In the contralateral visual cortex, long-term potentiation (LTP) and the phosphorylation levels of GluR1 at Ser 831 were increased in cPKCγ+/+ mice after MD. Interestingly, these levels could be downregulated by cPKCγ knockout compared to cPKCγ+/++MD mice (P < 0.001). Compared to the right eyes of WT mice, the amplitudes of a-waves and b-waves declined in deprived right eyes of mice after MD (P < 0.001). There were no significant differences when comparing cPKCγ+/+ and cPKCγ−/− mice with MD. Conclusions cPKCγ participates in the plasticity of the visual cortex after MD, which is characterized by increased LTP in the contralateral visual cortex, which may be a result of cPKCγ-mediated phosphorylation of GluR1 at Ser 831.
Collapse
|
17
|
Brown APY, Cossell L, Margrie TW. Visual Experience Regulates the Intrinsic Excitability of Visual Cortical Neurons to Maintain Sensory Function. Cell Rep 2020; 27:685-689.e4. [PMID: 30995467 PMCID: PMC6484778 DOI: 10.1016/j.celrep.2019.03.073] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 02/18/2019] [Accepted: 03/20/2019] [Indexed: 11/26/2022] Open
Abstract
This in vivo study shows that both intrinsic and sensory-evoked synaptic properties of layer 2/3 neurons in mouse visual cortex are modified by ongoing visual input. Following visual deprivation, intrinsic properties are significantly altered, although orientation selectivity across the population remains unchanged. We, therefore, suggest that cortical cells adjust their intrinsic excitability in an activity-dependent manner to compensate for changes in synaptic drive and maintain sensory network function. Intrinsic properties of V1 L2/3 neurons are modulated by ongoing sensory input Visually evoked synaptic responses are reduced after visual deprivation Deprivation has little effect on spiking or subthreshold orientation selectivity Cortical cells preserve sensory function despite long-term changes in synaptic drive
Collapse
Affiliation(s)
- Alexander P Y Brown
- The Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, 25 Howland Street, London W1T 4JG, UK
| | - Lee Cossell
- The Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, 25 Howland Street, London W1T 4JG, UK
| | - Troy W Margrie
- The Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, 25 Howland Street, London W1T 4JG, UK.
| |
Collapse
|
18
|
Vasalauskaite A, Morgan JE, Sengpiel F. Plasticity in Adult Mouse Visual Cortex Following Optic Nerve Injury. Cereb Cortex 2020; 29:1767-1777. [PMID: 30668659 PMCID: PMC6418869 DOI: 10.1093/cercor/bhy347] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 12/10/2018] [Accepted: 12/23/2018] [Indexed: 12/25/2022] Open
Abstract
Optic nerve (ON) injury is an established model of axonal injury which results in retrograde degeneration and death of retinal ganglion cells as well anterograde loss of transmission and Wallerian degeneration of the injured axons. While the local impact of ON crush has been extensively documented we know comparatively little about the functional changes that occur in higher visual structures such as primary visual cortex (V1). We explored the extent of adult cortical plasticity using ON crush in aged mice. V1 function of the contralateral hemisphere was assessed longitudinally by intrinsic signal imaging and 2-photon calcium imaging before and after ON crush. Functional imaging demonstrated an immediate shift in V1 ocular dominance towards the ipsilateral, intact eye, due to the expected almost complete loss of responses to contralateral eye stimulation. Surprisingly, within 2 weeks we observed a delayed increase in ipsilateral eye responses. Additionally, spontaneous activity in V1 was reduced, similar to the lesion projection zone after retinal lesions. The observed changes in V1 activity indicate that severe ON injury in adulthood evokes cortical plasticity not only cross-modally but also within the visual cortex; this plasticity may be best compared with that seen after retinal lesions.
Collapse
Affiliation(s)
| | - James E Morgan
- School of Optometry & Vision Sciences, Cardiff University, Maindy Road, Cardiff, UK
| | - Frank Sengpiel
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff, UK.,Neuroscience & Mental Health Research Institute, Cardiff University, Maindy Road, Cardiff, UK
| |
Collapse
|
19
|
Carceller H, Guirado R, Nacher J. Dark exposure affects plasticity‐related molecules and interneurons throughout the visual system during adulthood. J Comp Neurol 2020; 528:1349-1366. [DOI: 10.1002/cne.24832] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 11/16/2019] [Accepted: 11/22/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Hector Carceller
- Neurobiology Unit, Department of Cell Biology, Interdisciplinary Research Structure for Biotechnology and Biomedicine (BIOTECMED)Universitat de Valencia Valencia Spain
| | - Ramon Guirado
- Neurobiology Unit, Department of Cell Biology, Interdisciplinary Research Structure for Biotechnology and Biomedicine (BIOTECMED)Universitat de Valencia Valencia Spain
| | - Juan Nacher
- Neurobiology Unit, Department of Cell Biology, Interdisciplinary Research Structure for Biotechnology and Biomedicine (BIOTECMED)Universitat de Valencia Valencia Spain
- CIBERSAM: Spanish National Network for Research in Mental Health Madrid Spain
- Fundación Investigación Hospital Clínico de Valencia, INCLIVA Valencia Spain
| |
Collapse
|
20
|
Grieco SF, Wang G, Mahapatra A, Lai C, Holmes TC, Xu X. Neuregulin and ErbB expression is regulated by development and sensory experience in mouse visual cortex. J Comp Neurol 2019; 528:419-432. [PMID: 31454079 PMCID: PMC6901715 DOI: 10.1002/cne.24762] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/22/2019] [Accepted: 08/14/2019] [Indexed: 01/14/2023]
Abstract
Neuregulins (NRGs) are protein ligands that impact neural development and circuit function. NRGs signal through the ErbB receptor tyrosine kinase family. NRG1/ErbB4 signaling in parvalbumin-expressing (PV) inhibitory interneurons is critical for visual cortical plasticity. There are multiple types of NRGs and ErbBs that can potentially contribute to visual cortical plasticity at different developmental stages. Thus, it is important to understand the normal developmental expression profiles of NRGs and ErbBs in specific neuron types in the visual cortex, and to study whether and how their expression changes in PV inhibitory neurons and excitatory neurons track with sensory perturbation. Cell type-specific translating ribosome affinity purification and qPCR was used to compare mRNA expression of nrg1,2,3,4 and erbB1,2,3,4 in PV and excitatory neurons in mouse visual cortex. We show that the expression of nrg1 and nrg3 decreases in PV neurons at the critical period peak, postnatal day 28 (P28) after monocular deprivation and dark rearing, and in the adult cortex (at P104) after 2-week long dark exposure. In contrast, nrg1 expression by excitatory neurons is unchanged at P28 and P104 following sensory deprivation, whereas nrg3 expression by excitatory neurons shows changes depending on the age and the mode of sensory deprivation. ErbB4 expression in PV neurons remains consistently high and does not appear to change in response to sensory deprivation. These data provide new important details of cell type-specific NRG/ErbB expression in the visual cortex and support that NRG1/ErbB4 signaling is implicated in both critical period and adult visual cortical plasticity.
Collapse
Affiliation(s)
- Steven F Grieco
- Department of Anatomy and Neurobiology, School of Medicine, University of California, Irvine, California
| | - Gina Wang
- Department of Anatomy and Neurobiology, School of Medicine, University of California, Irvine, California
| | - Ananya Mahapatra
- Department of Anatomy and Neurobiology, School of Medicine, University of California, Irvine, California
| | - Cary Lai
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana
| | - Todd C Holmes
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California
| | - Xiangmin Xu
- Department of Anatomy and Neurobiology, School of Medicine, University of California, Irvine, California.,Department of Biomedical Engineering, University of California, Irvine, California
| |
Collapse
|
21
|
Modification of Peak Plasticity Induced by Brief Dark Exposure. Neural Plast 2019; 2019:3198285. [PMID: 31565047 PMCID: PMC6745115 DOI: 10.1155/2019/3198285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 05/13/2019] [Accepted: 05/22/2019] [Indexed: 11/29/2022] Open
Abstract
The capacity for neural plasticity in the mammalian central visual system adheres to a temporal profile in which plasticity peaks early in postnatal development and then declines to reach enduring negligible levels. Early studies to delineate the critical period in cats employed a fixed duration of monocular deprivation to measure the extent of ocular dominance changes induced at different ages. The largest deprivation effects were observed at about 4 weeks postnatal, with a steady decline in plasticity thereafter so that by about 16 weeks only small changes were measured. The capacity for plasticity is regulated by a changing landscape of molecules in the visual system across the lifespan. Studies in rodents and cats have demonstrated that the critical period can be altered by environmental or pharmacological manipulations that enhance plasticity at ages when it would normally be low. Immersion in complete darkness for long durations (dark rearing) has long been known to alter plasticity capacity by modifying plasticity-related molecules and slowing progress of the critical period. In this study, we investigated the possibility that brief darkness (dark exposure) imposed just prior to the critical period peak can enhance the level of plasticity beyond that observed naturally. We examined the level of plasticity by measuring two sensitive markers of monocular deprivation, namely, soma size of neurons and neurofilament labeling within the dorsal lateral geniculate nucleus. Significantly larger modification of soma size, but not neurofilament labeling, was observed at the critical period peak when dark exposure preceded monocular deprivation. This indicated that the natural plasticity ceiling is modifiable and also that brief darkness does not simply slow progress of the critical period. As an antecedent to traditional amblyopia treatment, darkness may increase treatment efficacy even at ages when plasticity is at its highest.
Collapse
|
22
|
Abstract
It has been shown that the visual acuity loss experienced by the deprived eye of kittens following an early period of monocular deprivation (MD) can be alleviated rapidly following 10 days of complete darkness when imposed even as late as 14 weeks of age. To examine whether 10 days of darkness conferred benefits at any age, we measured the extent of recovery of the visual acuity of the deprived eye following the darkness imposed on adult cats that had received the same early period of MD as used in prior experiments conducted on kittens. Parallel studies conducted on different animals examined the extent to which darkness changed the magnitude of the MD-induced laminar differences of the cell soma size and immunoreactivity for the neurofilament (NF) protein in the dorsal lateral geniculate nucleus (dLGN). The results indicated that 10 days of darkness imposed at one year of age neither alleviated the acuity loss of the deprived eye induced by an earlier period of MD nor did it decrease the concurrent lamina differences of the soma size or NF loss in the dLGN.
Collapse
|
23
|
Milczarek MM, Vann SD, Sengpiel F. Spatial Memory Engram in the Mouse Retrosplenial Cortex. Curr Biol 2018; 28:1975-1980.e6. [PMID: 29887312 PMCID: PMC6013279 DOI: 10.1016/j.cub.2018.05.002] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 04/27/2018] [Accepted: 05/01/2018] [Indexed: 01/19/2023]
Abstract
Memory relies on lasting adaptations of neuronal properties elicited by stimulus-driven plastic changes [1]. The strengthening (and weakening) of synapses results in the establishment of functional ensembles. It is presumed that such ensembles (or engrams) are activated during memory acquisition and re-activated upon memory retrieval. The retrosplenial cortex (RSC) has emerged as a key brain area supporting memory [2], including episodic and topographical memory in humans [3, 4, 5], as well as spatial memory in rodents [6, 7]. Dysgranular RSC is densely connected with dorsal stream visual areas [8] and contains place-like and head-direction cells, making it a prime candidate for integrating navigational information [9]. While previous reports [6, 10] describe the recruitment of RSC ensembles during navigational tasks, such ensembles have never been tracked long enough to provide evidence of stable engrams and have not been related to the retention of long-term memory. Here, we used in vivo 2-photon imaging to analyze patterns of activity of over 6,000 neurons within dysgranular RSC. Eight mice were trained on a spatial memory task. Learning was accompanied by the gradual emergence of a context-specific pattern of neuronal activity over a 3-week period, which was re-instated upon retrieval more than 3 weeks later. The stability of this memory engram was predictive of the degree of forgetting; more stable engrams were associated with better performance. This provides direct evidence for the interdependence of spatial memory consolidation and RSC engram formation. Our results demonstrate the participation of RSC in spatial memory storage at the level of neuronal ensembles. Longitudinal C-fos imaging reveals retrosplenial spatial memory engrams in mice Engrams become progressively more stable with learning and are maintained over weeks The degree of memory retention is related to the stability of the engrams
Collapse
|
24
|
Duffy KR, Fong MF, Mitchell DE, Bear MF. Recovery from the anatomical effects of long-term monocular deprivation in cat lateral geniculate nucleus. J Comp Neurol 2017; 526:310-323. [PMID: 29023717 DOI: 10.1002/cne.24336] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 10/05/2017] [Accepted: 10/06/2017] [Indexed: 11/06/2022]
Abstract
Monocular deprivation (MD) imposed early in postnatal life elicits profound structural and functional abnormalities throughout the primary visual pathway. The ability of MD to modify neurons within the visual system is restricted to a so-called critical period that, for cats, peaks at about one postnatal month and declines thereafter so that by about 3 months of age MD has little effect. Recovery from the consequences of MD likewise adheres to a critical period that ends by about 3 months of age, after which the effects of deprivation are thought to be permanent and without capacity for reversal. The attenuation of plasticity beyond early development is a formidable obstacle for conventional therapies to stimulate recovery from protracted visual deprivation. In the current study we examined the efficacy of dark exposure and retinal inactivation with tetrodotoxin to promote anatomical recovery in the dorsal lateral geniculate nuclues (dLGN) from long-term MD started at the peak of the critical period. Whereas 10 days of dark exposure or binocular retinal inactivation were not better at promoting recovery than conventional treatment with reverse occlusion, inactivation of only the non-deprived (fellow) eye for 10 days produced a complete restoration of neuron soma size, and also reversed the significant loss of neurofilament protein within originally deprived dLGN layers. These results reveal a capacity for neural plasticity and recovery that is larger than anything previously observed following protracted MD in cat, and they highlight a possibility for alternative therapies applied at ages thought to be recalcitrant to recovery.
Collapse
Affiliation(s)
- Kevin R Duffy
- Department of Psychology & Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Ming-Fai Fong
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Donald E Mitchell
- Department of Psychology & Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Mark F Bear
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts
| |
Collapse
|
25
|
Murase S, Lantz CL, Quinlan EM. Light reintroduction after dark exposure reactivates plasticity in adults via perisynaptic activation of MMP-9. eLife 2017; 6:27345. [PMID: 28875930 PMCID: PMC5630258 DOI: 10.7554/elife.27345] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 09/05/2017] [Indexed: 12/12/2022] Open
Abstract
The sensitivity of ocular dominance to regulation by monocular deprivation is the canonical model of plasticity confined to a critical period. However, we have previously shown that visual deprivation through dark exposure (DE) reactivates critical period plasticity in adults. Previous work assumed that the elimination of visual input was sufficient to enhance plasticity in the adult mouse visual cortex. In contrast, here we show that light reintroduction (LRx) after DE is responsible for the reactivation of plasticity. LRx triggers degradation of the ECM, which is blocked by pharmacological inhibition or genetic ablation of matrix metalloproteinase-9 (MMP-9). LRx induces an increase in MMP-9 activity that is perisynaptic and enriched at thalamo-cortical synapses. The reactivation of plasticity by LRx is absent in Mmp9−/− mice, and is rescued by hyaluronidase, an enzyme that degrades core ECM components. Thus, the LRx-induced increase in MMP-9 removes constraints on structural and functional plasticity in the mature cortex.
Collapse
Affiliation(s)
- Sachiko Murase
- Neuroscience and Cognitive Sciences Program, Department of Biology, University of Maryland, Maryland, United States
| | - Crystal L Lantz
- Neuroscience and Cognitive Sciences Program, Department of Biology, University of Maryland, Maryland, United States
| | - Elizabeth M Quinlan
- Neuroscience and Cognitive Sciences Program, Department of Biology, University of Maryland, Maryland, United States
| |
Collapse
|
26
|
Fox K, Stryker M. Integrating Hebbian and homeostatic plasticity: introduction. Philos Trans R Soc Lond B Biol Sci 2017; 372:20160413. [PMID: 28093560 PMCID: PMC5247598 DOI: 10.1098/rstb.2016.0413] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2016] [Indexed: 01/13/2023] Open
Abstract
Hebbian plasticity is widely considered to be the mechanism by which information can be coded and retained in neurons in the brain. Homeostatic plasticity moves the neuron back towards its original state following a perturbation, including perturbations produced by Hebbian plasticity. How then does homeostatic plasticity avoid erasing the Hebbian coded information? To understand how plasticity works in the brain, and therefore to understand learning, memory, sensory adaptation, development and recovery from injury, requires development of a theory of plasticity that integrates both forms of plasticity into a whole. In April 2016, a group of computational and experimental neuroscientists met in London at a discussion meeting hosted by the Royal Society to identify the critical questions in the field and to frame the research agenda for the next steps. Here, we provide a brief introduction to the papers arising from the meeting and highlight some of the themes to have emerged from the discussions.This article is part of the themed issue 'Integrating Hebbian and homeostatic plasticity'.
Collapse
Affiliation(s)
- Kevin Fox
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | - Michael Stryker
- Center for Integrative Neuroscience, University of California, 675 Nelson Rising Lane, San Francisco, CA 94158, USA
- Department of Physiology, University of California, San Francisco, CA 94143, USA
| |
Collapse
|