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Chauhan K, Neiman AB, Tass PA. Synaptic reorganization of synchronized neuronal networks with synaptic weight and structural plasticity. PLoS Comput Biol 2024; 20:e1012261. [PMID: 38980898 DOI: 10.1371/journal.pcbi.1012261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 06/20/2024] [Indexed: 07/11/2024] Open
Abstract
Abnormally strong neural synchronization may impair brain function, as observed in several brain disorders. We computationally study how neuronal dynamics, synaptic weights, and network structure co-emerge, in particular, during (de)synchronization processes and how they are affected by external perturbation. To investigate the impact of different types of plasticity mechanisms, we combine a network of excitatory integrate-and-fire neurons with different synaptic weight and/or structural plasticity mechanisms: (i) only spike-timing-dependent plasticity (STDP), (ii) only homeostatic structural plasticity (hSP), i.e., without weight-dependent pruning and without STDP, (iii) a combination of STDP and hSP, i.e., without weight-dependent pruning, and (iv) a combination of STDP and structural plasticity (SP) that includes hSP and weight-dependent pruning. To accommodate the diverse time scales of neuronal firing, STDP, and SP, we introduce a simple stochastic SP model, enabling detailed numerical analyses. With tools from network theory, we reveal that structural reorganization may remarkably enhance the network's level of synchrony. When weaker contacts are preferentially eliminated by weight-dependent pruning, synchrony is achieved with significantly sparser connections than in randomly structured networks in the STDP-only model. In particular, the strengthening of contacts from neurons with higher natural firing rates to those with lower rates and the weakening of contacts in the opposite direction, followed by selective removal of weak contacts, allows for strong synchrony with fewer connections. This activity-led network reorganization results in the emergence of degree-frequency, degree-degree correlations, and a mixture of degree assortativity. We compare the stimulation-induced desynchronization of synchronized states in the STDP-only model (i) with the desynchronization of models (iii) and (iv). The latter require stimuli of significantly higher intensity to achieve long-term desynchronization. These findings may inform future pre-clinical and clinical studies with invasive or non-invasive stimulus modalities aiming at inducing long-lasting relief of symptoms, e.g., in Parkinson's disease.
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Affiliation(s)
- Kanishk Chauhan
- Department of Physics and Astronomy, Ohio University, Athens, Ohio, United States of America
- Neuroscience Program, Ohio University, Athens, Ohio, United States of America
| | - Alexander B Neiman
- Department of Physics and Astronomy, Ohio University, Athens, Ohio, United States of America
- Neuroscience Program, Ohio University, Athens, Ohio, United States of America
| | - Peter A Tass
- Department of Neurosurgery, Stanford University, Stanford, California, United States of America
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2
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Roth RH, Ding JB. Cortico-basal ganglia plasticity in motor learning. Neuron 2024:S0896-6273(24)00449-5. [PMID: 39002543 DOI: 10.1016/j.neuron.2024.06.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 05/29/2024] [Accepted: 06/17/2024] [Indexed: 07/15/2024]
Abstract
One key function of the brain is to control our body's movements, allowing us to interact with the world around us. Yet, many motor behaviors are not innate but require learning through repeated practice. Among the brain's motor regions, the cortico-basal ganglia circuit is particularly crucial for acquiring and executing motor skills, and neuronal activity in these regions is directly linked to movement parameters. Cell-type-specific adaptations of activity patterns and synaptic connectivity support the learning of new motor skills. Functionally, neuronal activity sequences become structured and associated with learned movements. On the synaptic level, specific connections become potentiated during learning through mechanisms such as long-term synaptic plasticity and dendritic spine dynamics, which are thought to mediate functional circuit plasticity. These synaptic and circuit adaptations within the cortico-basal ganglia circuitry are thus critical for motor skill acquisition, and disruptions in this plasticity can contribute to movement disorders.
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Affiliation(s)
- Richard H Roth
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA.
| | - Jun B Ding
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA; The Phil & Penny Knight Initiative for Brain Resilience at the Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, USA.
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3
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Kelly-Castro EC, Shear R, Dindigal AH, Bhagwat M, Zhang H. MARK1 regulates dendritic spine morphogenesis and cognitive functions in vivo. Exp Neurol 2024; 376:114752. [PMID: 38484863 DOI: 10.1016/j.expneurol.2024.114752] [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: 12/14/2023] [Revised: 02/14/2024] [Accepted: 03/10/2024] [Indexed: 03/23/2024]
Abstract
Dendritic spines play a pivotal role in synaptic communication and are crucial for learning and memory processes. Abnormalities in spine morphology and plasticity are observed in neurodevelopmental and neuropsychiatric disorders, yet the underlying signaling mechanisms remain poorly understood. The microtubule affinity regulating kinase 1 (MARK1) has been implicated in neurodevelopmental disorders, and the MARK1 gene shows accelerated evolution in the human lineage suggesting a role in cognition. However, the in vivo role of MARK1 in synaptogenesis and cognitive functions remains unknown. Here we show that forebrain-specific conditional knockout (cKO) of Mark1 in mice causes defects in dendritic spine morphogenesis in hippocampal CA1 pyramidal neurons with a significant reduction in spine density. In addition, we found loss of MARK1 causes synaptic accumulation of GKAP and GluA2. Furthermore, we found that MARK1 cKO mice show defects in spatial learning in the Morris water maze and reduced anxiety-like behaviors in the elevated plus maze. Taken together, our data show a novel role for MARK1 in regulating dendritic spine morphogenesis and cognitive functions in vivo.
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Affiliation(s)
- Emily C Kelly-Castro
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, USA
| | - Rebecca Shear
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, USA
| | - Ankitha H Dindigal
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, USA
| | - Maitreyee Bhagwat
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, USA
| | - Huaye Zhang
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, USA.
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4
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Dunton KL, Hedrick NG, Meamardoost S, Ren C, Howe JR, Wang J, Root CM, Gunawan R, Komiyama T, Zhang Y, Hwang EJ. Divergent Learning-Related Transcriptional States of Cortical Glutamatergic Neurons. J Neurosci 2024; 44:e0302232023. [PMID: 38238073 PMCID: PMC10919205 DOI: 10.1523/jneurosci.0302-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 09/30/2023] [Accepted: 11/10/2023] [Indexed: 03/08/2024] Open
Abstract
Experience-dependent gene expression reshapes neural circuits, permitting the learning of knowledge and skills. Most learning involves repetitive experiences during which neurons undergo multiple stages of functional and structural plasticity. Currently, the diversity of transcriptional responses underlying dynamic plasticity during repetition-based learning is poorly understood. To close this gap, we analyzed single-nucleus transcriptomes of L2/3 glutamatergic neurons of the primary motor cortex after 3 d motor skill training or home cage control in water-restricted male mice. "Train" and "control" neurons could be discriminated with high accuracy based on expression patterns of many genes, indicating that recent experience leaves a widespread transcriptional signature across L2/3 neurons. These discriminating genes exhibited divergent modes of coregulation, differentiating neurons into discrete clusters of transcriptional states. Several states showed gene expressions associated with activity-dependent plasticity. Some of these states were also prominent in the previously published reference, suggesting that they represent both spontaneous and task-related plasticity events. Markedly, however, two states were unique to our dataset. The first state, further enriched by motor training, showed gene expression suggestive of late-stage plasticity with repeated activation, which is suitable for expected emergent neuronal ensembles that stably retain motor learning. The second state, equally found in both train and control mice, showed elevated levels of metabolic pathways and norepinephrine sensitivity, suggesting a response to common experiences specific to our experimental conditions, such as water restriction or circadian rhythm. Together, we uncovered divergent transcriptional responses across L2/3 neurons, each potentially linked with distinct features of repetition-based motor learning such as plasticity, memory, and motivation.
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Affiliation(s)
- Katie L Dunton
- Department of Cell and Molecular Biology, College of the Environment and Life Sciences, University of Rhode Island, Kingston 02881, Rhode Island
| | - Nathan G Hedrick
- Department of Neurobiology, Center for Neural Circuits and Behavior, Department of Neurosciences, and Halıcıoğlu Data Science Institute, University of California San Diego, La Jolla 92093, California
| | - Saber Meamardoost
- Department of Chemical and Biological Engineering, University at Buffalo-SUNY, Buffalo 14260, New York
| | - Chi Ren
- Department of Neurobiology, Center for Neural Circuits and Behavior, Department of Neurosciences, and Halıcıoğlu Data Science Institute, University of California San Diego, La Jolla 92093, California
| | - James R Howe
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, La Jolla 92093, California
- Neurosciences Graduate Program, University of California San Diego, La Jolla 92093, California
| | - Jing Wang
- Department of Cell and Molecular Biology, College of the Environment and Life Sciences, University of Rhode Island, Kingston 02881, Rhode Island
| | - Cory M Root
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, La Jolla 92093, California
| | - Rudiyanto Gunawan
- Department of Chemical and Biological Engineering, University at Buffalo-SUNY, Buffalo 14260, New York
| | - Takaki Komiyama
- Department of Neurobiology, Center for Neural Circuits and Behavior, Department of Neurosciences, and Halıcıoğlu Data Science Institute, University of California San Diego, La Jolla 92093, California
| | - Ying Zhang
- Department of Cell and Molecular Biology, College of the Environment and Life Sciences, University of Rhode Island, Kingston 02881, Rhode Island
| | - Eun Jung Hwang
- Department of Neurobiology, Center for Neural Circuits and Behavior, Department of Neurosciences, and Halıcıoğlu Data Science Institute, University of California San Diego, La Jolla 92093, California
- Cell Biology and Anatomy, Chicago Medical School, Stanson Toshok Center for Brain Function and Repair, Rosalind Franklin University of Medicine and Science, North Chicago 60064, Illinois
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5
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Kelly-Castro EC, Shear R, Dindigal AH, Bhagwat M, Zhang H. MARK1 regulates dendritic spine morphogenesis and cognitive functions in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.03.569757. [PMID: 38105977 PMCID: PMC10723299 DOI: 10.1101/2023.12.03.569757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Dendritic spines play a pivotal role in synaptic communication and are crucial for learning and memory processes. Abnormalities in spine morphology and plasticity are observed in neurodevelopmental and neuropsychiatric disorders, yet the underlying signaling mechanisms remain poorly understood. The microtubule affinity regulating kinase 1 (MARK1) has been implicated in neurodevelopmental disorders, and the MARK1 gene shows accelerated evolution in the human lineage suggesting a role in cognition. However, the in vivo role of MARK1 in synaptogenesis and cognitive functions remains unknown. Here we show that forebrain-specific conditional knockout (cKO) of Mark1 causes defects in dendritic spine morphogenesis in hippocampal CA1 pyramidal neurons with a significant reduction in spine density. In addition, we found that MARK1 cKO mice show defects in spatial learning in the Morris Water Maze and reduced anxiety-like behaviors in the Elevated Plus Maze. Furthermore, we found loss of MARK1 causes synaptic accumulation of GKAP and GluR2. Taken together, our data show a novel role for MARK1 in regulating dendritic spine morphogenesis and cognitive functions in vivo .
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6
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Malakasis N, Chavlis S, Poirazi P. Synaptic turnover promotes efficient learning in bio-realistic spiking neural networks. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.22.541722. [PMID: 37292929 PMCID: PMC10245885 DOI: 10.1101/2023.05.22.541722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
While artificial machine learning systems achieve superhuman performance in specific tasks such as language processing, image and video recognition, they do so use extremely large datasets and huge amounts of power. On the other hand, the brain remains superior in several cognitively challenging tasks while operating with the energy of a small lightbulb. We use a biologically constrained spiking neural network model to explore how the neural tissue achieves such high efficiency and assess its learning capacity on discrimination tasks. We found that synaptic turnover, a form of structural plasticity, which is the ability of the brain to form and eliminate synapses continuously, increases both the speed and the performance of our network on all tasks tested. Moreover, it allows accurate learning using a smaller number of examples. Importantly, these improvements are most significant under conditions of resource scarcity, such as when the number of trainable parameters is halved and when the task difficulty is increased. Our findings provide new insights into the mechanisms that underlie efficient learning in the brain and can inspire the development of more efficient and flexible machine learning algorithms.
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Affiliation(s)
- Nikos Malakasis
- School of Medicine, University of Crete, Heraklion 70013, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion 70013, Greece
| | - Spyridon Chavlis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion 70013, Greece
| | - Panayiota Poirazi
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion 70013, Greece
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7
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Markiewicz-Gospodarek A, Markiewicz R, Borowski B, Dobrowolska B, Łoza B. Self-Regulatory Neuronal Mechanisms and Long-Term Challenges in Schizophrenia Treatment. Brain Sci 2023; 13:brainsci13040651. [PMID: 37190616 DOI: 10.3390/brainsci13040651] [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: 03/30/2023] [Revised: 04/04/2023] [Accepted: 04/11/2023] [Indexed: 05/17/2023] Open
Abstract
Schizophrenia is a chronic and relapsing disorder that is characterized not only by delusions and hallucinations but also mainly by the progressive development of cognitive and social deficits. These deficits are related to impaired synaptic plasticity and impaired neurotransmission in the nervous system. Currently, technological innovations and medical advances make it possible to use various self-regulatory methods to improve impaired synaptic plasticity. To evaluate the therapeutic effect of various rehabilitation methods, we reviewed methods that modify synaptic plasticity and improve the cognitive and executive processes of patients with a diagnosis of schizophrenia. PubMed, Scopus, and Google Scholar bibliographic databases were searched with the keywords mentioned below. A total of 555 records were identified. Modern methods of schizophrenia therapy with neuroplastic potential, including neurofeedback, transcranial magnetic stimulation, transcranial direct current stimulation, vagus nerve stimulation, virtual reality therapy, and cognitive remediation therapy, were reviewed and analyzed. Since randomized controlled studies of long-term schizophrenia treatment do not exceed 2-3 years, and the pharmacological treatment itself has an incompletely estimated benefit-risk ratio, treatment methods based on other paradigms, including neuronal self-regulatory and neural plasticity mechanisms, should be considered. Methods available for monitoring neuroplastic effects in vivo (e.g., fMRI, neuropeptides in serum), as well as unfavorable parameters (e.g., features of the metabolic syndrome), enable individualized monitoring of the effectiveness of long-term treatment of schizophrenia.
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Affiliation(s)
| | - Renata Markiewicz
- Department of Neurology, Neurological and Psychiatric Nursing, Medical University of Lublin, 20-093 Lublin, Poland
| | - Bartosz Borowski
- Students Scientific Association at the Department of Human Anatomy, Medical University of Lublin, 20-090 Lublin, Poland
| | - Beata Dobrowolska
- Department of Holistic Care and Management in Nursing, Medical University of Lublin, 20-081 Lublin, Poland
| | - Bartosz Łoza
- Department of Psychiatry, Medical University of Warsaw, 02-091 Warsaw, Poland
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8
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Burnsed J, Matysik W, Yang L, Sun H, Joshi S, Kapur J. Increased glutamatergic synaptic transmission during development in layer II/III mouse motor cortex pyramidal neurons. Cereb Cortex 2023; 33:4645-4653. [PMID: 36137566 PMCID: PMC10110452 DOI: 10.1093/cercor/bhac368] [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: 04/01/2022] [Revised: 08/22/2022] [Accepted: 08/23/2022] [Indexed: 11/13/2022] Open
Abstract
Postnatal maturation of the motor cortex is vital to developing a variety of functions, including the capacity for motor learning. The first postnatal weeks involve many neuronal and synaptic changes, which differ by region and layer, likely due to different functions and needs during development. Motor cortex layer II/III is critical to receiving and integrating inputs from somatosensory cortex and generating attentional signals that are important in motor learning and planning. Here, we examined the neuronal and synaptic changes occurring in layer II/III pyramidal neurons of the mouse motor cortex from the neonatal (postnatal day 10) to young adult (postnatal day 30) period, using a combination of electrophysiology and biochemical measures of glutamatergic receptor subunits. There are several changes between p10 and p30 in these neurons, including increased dendritic branching, neuronal excitability, glutamatergic synapse number and synaptic transmission. These changes are critical to ongoing plasticity and capacity for motor learning during development. Understanding these changes will help inform future studies examining the impact of early-life injury and experiences on motor learning and development capacity.
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Affiliation(s)
- Jennifer Burnsed
- Department of Pediatrics, University of Virginia, Charlottesville, Virginia 22908-0386, USA
- Department of Neurology, University of Virginia, Charlottesville, Virginia 22908-0386, USA
| | - Weronika Matysik
- Department of Pediatrics, University of Virginia, Charlottesville, Virginia 22908-0386, USA
| | - Lu Yang
- Department of Neurology, University of Virginia, Charlottesville, Virginia 22908-0386, USA
- Department of Pediatrics, Shandong University, Jian, Shandong 250012, China
| | - Huayu Sun
- Department of Neurology, University of Virginia, Charlottesville, Virginia 22908-0386, USA
| | - Suchitra Joshi
- Department of Neurology, University of Virginia, Charlottesville, Virginia 22908-0386, USA
| | - Jaideep Kapur
- Department of Neurology, University of Virginia, Charlottesville, Virginia 22908-0386, USA
- Department of Neuroscience, University of Virginia, Charlottesville, Virginia 22908-0386, USA
- Brain Institute, University of Virginia, Charlottesville, Virginia 22908-0386, USA
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Kida H, Kawakami R, Sakai K, Otaku H, Imamura K, Han TZ, Sakimoto Y, Mitsushima D. Motor training promotes both synaptic and intrinsic plasticity of layer V pyramidal neurons in the primary motor cortex. J Physiol 2023; 601:335-353. [PMID: 36515167 DOI: 10.1113/jp283755] [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: 11/01/2022] [Accepted: 11/23/2022] [Indexed: 12/15/2022] Open
Abstract
Layer V neurons in the primary motor cortex (M1) are important for motor skill learning. Since pretreatment of either CNQX or APV in rat M1 layer V impaired rotor rod learning, we analysed training-induced synaptic plasticity by whole-cell patch-clamp technique in acute brain slices. Rats trained for 1 day showed a decrease in small inhibitory postsynaptic current (mIPSC) frequency and an increase in the paired-pulse ratio of evoked IPSCs, suggesting a transient decrease in presynaptic GABA release in the early phase. Rats trained for 2 days showed an increase in miniature excitatory postsynaptic current (mEPSC) amplitudes/frequency and elevated AMPA/NMDA ratios, suggesting a long-term strengthening of AMPA receptor-mediated excitatory synapses. Importantly, rotor rod performance in trained rats was correlated with the mean mEPSC amplitude and the frequency obtained from that animal. In current-clamp analysis, 1-day-trained rats transiently decreased the current-induced firing rate, while 2-day-trained rats returned to pre-training levels, suggesting dynamic changes in intrinsic properties. Furthermore, western blot analysis of layer V detected decreased phosphorylation of Ser408-409 in GABAA receptor β3 subunits in 1-day-trained rats, and increased phosphorylation of Ser831 in AMPA receptor GluA1 subunits in 2-day-trained rats. Finally, live-imaging analysis of Thy1-YFP transgenic mice showed that the training rapidly recruited a substantial number of spines for long-term plasticity in M1 layer V neurons. Taken together, these results indicate that motor training induces complex and diverse plasticity in M1 layer V pyramidal neurons. KEY POINTS: Here we examined motor training-induced synaptic and intrinsic plasticity of layer V pyramidal neurons in the primary motor cortex. The training reduced presynaptic GABA release in the early phase, but strengthened AMPA receptor-mediated excitatory synapses in the later phase: acquired motor performance after training correlated with the strength of excitatory synapses rather than inhibitory synapses. As to the intrinsic property, the training transiently decreased the firing rate in the early phase, but returned to pre-training levels in the later phase. Western blot analysis detected decreased phosphorylation of Ser408-409 in GABAA receptor β3 subunits in the acute phase, and increased phosphorylation of Ser831 in AMPA receptor GluA1 subunits in the later phase. Live-imaging analysis of Thy1-YFP transgenic mice showed rapid and long-term spine plasticity in M1 layer V neurons, suggesting training-induced increases in self-entropy per spine.
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Affiliation(s)
- H Kida
- Department of Physiology, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan
| | - R Kawakami
- Department of Molecular Medicine for Pathogenesis, Graduate School of Medicine, Ehime University, Ehime, Japan
| | - K Sakai
- Department of Physiology, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan
| | - H Otaku
- Department of Physiology, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan
| | - K Imamura
- Department of Physiology, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan
| | - Thiri-Zin Han
- Department of Physiology, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan
| | - Y Sakimoto
- Department of Physiology, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan
| | - Dai Mitsushima
- Department of Physiology, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan.,The Research Institute for Time Studies, Yamaguchi University, Yamaguchi, Japan
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Bonilla-Quintana M, Rangamani P. Can biophysical models of dendritic spines be used to explore synaptic changes associated with addiction? Phys Biol 2022; 19. [PMID: 35508164 DOI: 10.1088/1478-3975/ac6cbe] [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: 01/06/2022] [Accepted: 05/04/2022] [Indexed: 11/11/2022]
Abstract
Effective treatments that prevent or reduce drug relapse vulnerability should be developed to relieve the high burden of drug addiction on society. This will only be possible by enhancing the understanding of the molecular mechanisms underlying the neurobiology of addiction. Recent experimental data have shown that dendritic spines, small protrusions from the dendrites that receive excitatory input, of spiny neurons in the nucleus accumbens exhibit morphological changes during drug exposure and withdrawal. Moreover, these changes relate to the characteristic drug-seeking behavior of addiction. However, due to the complexity of the dendritic spines, we do not yet fully understand the processes underlying their structural changes in response to different inputs. We propose that biophysical models can enhance the current understanding of these processes by incorporating different, and sometimes, discrepant experimental data to identify the shared underlying mechanisms and generate experimentally testable hypotheses. This review aims to give an up-to-date report on biophysical models of dendritic spines, focusing on those models that describe their shape changes, which are well-known to relate to learning and memory. Moreover, it examines how these models can enhance our understanding of the effect of the drugs and the synaptic changes during withdrawal, as well as during neurodegenerative disease progression such as Alzheimer's disease.
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Affiliation(s)
- Mayte Bonilla-Quintana
- Mechanical Aerospace Engineering, University of California San Diego, 9500 Gilman Drive, La Jolla, California, 92093-0021, UNITED STATES
| | - Padmini Rangamani
- Mechanical Aerospace Engineering, University of California San Diego, 9500 Gilman Drive, La Jolla, California, 92093-0021, UNITED STATES
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11
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Ortega-de San Luis C, Ryan TJ. Understanding the physical basis of memory: Molecular mechanisms of the engram. J Biol Chem 2022; 298:101866. [PMID: 35346687 PMCID: PMC9065729 DOI: 10.1016/j.jbc.2022.101866] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 03/08/2022] [Accepted: 03/11/2022] [Indexed: 12/18/2022] Open
Abstract
Memory, defined as the storage and use of learned information in the brain, is necessary to modulate behavior and critical for animals to adapt to their environments and survive. Despite being a cornerstone of brain function, questions surrounding the molecular and cellular mechanisms of how information is encoded, stored, and recalled remain largely unanswered. One widely held theory is that an engram is formed by a group of neurons that are active during learning, which undergoes biochemical and physical changes to store information in a stable state, and that are later reactivated during recall of the memory. In the past decade, the development of engram labeling methodologies has proven useful to investigate the biology of memory at the molecular and cellular levels. Engram technology allows the study of individual memories associated with particular experiences and their evolution over time, with enough experimental resolution to discriminate between different memory processes: learning (encoding), consolidation (the passage from short-term to long-term memories), and storage (the maintenance of memory in the brain). Here, we review the current understanding of memory formation at a molecular and cellular level by focusing on insights provided using engram technology.
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Affiliation(s)
- Clara Ortega-de San Luis
- School of Biochemistry and Immunology and Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland.
| | - Tomás J Ryan
- School of Biochemistry and Immunology and Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland; Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia; Child & Brain Development Program, Canadian Institute for Advanced Research (CIFAR), Toronto, Ontario, Canada.
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12
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Lee C, Kim Y, Kaang BK. The primary motor cortex: the hub of motor learning in rodents. Neuroscience 2022; 485:163-170. [PMID: 35051529 DOI: 10.1016/j.neuroscience.2022.01.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 01/07/2022] [Accepted: 01/10/2022] [Indexed: 12/31/2022]
Abstract
The primary motor cortex, a dynamic center for overall motion control and decision making, undergoes significant alterations upon neural stimulation. Over the last few decades, data from numerous studies using rodent models have improved our understanding of the morphological and functional plasticity of the primary motor cortex. In particular, spatially specific formation of dendritic spines and their maintenance during distinct behaviors is considered crucial for motor learning. However, whether the modifications of specific synapses are associated with motor learning should be studied further. In this review, we summarized the findings of prior studies on the features and dynamics of the primary motor cortex in rodents.
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Affiliation(s)
- Chaery Lee
- School of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Yeonjun Kim
- Interdisciplinary Program in Neuroscience, Seoul National University, Seoul 08826, Republic of Korea
| | - Bong-Kiun Kaang
- School of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea.
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13
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Dyer MS, Woodhouse A, Blizzard CA. Cytoplasmic Human TDP-43 Mislocalization Induces Widespread Dendritic Spine Loss in Mouse Upper Motor Neurons. Brain Sci 2021; 11:brainsci11070883. [PMID: 34209287 PMCID: PMC8301870 DOI: 10.3390/brainsci11070883] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/25/2021] [Accepted: 06/27/2021] [Indexed: 11/16/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is defined by the destruction of upper- and lower motor neurons. Post-mortem, nearly all ALS cases are positive for cytoplasmic aggregates containing the DNA/RNA binding protein TDP-43. Recent studies indicate that this pathogenic mislocalization of TDP-43 may participate in generating hyperexcitability of the upper motor neurons, the earliest detectable change in ALS patients, yet the mechanisms driving this remain unclear. We investigated how mislocalisation of TDP-43 could initiate network dysfunction in ALS. We employed a tetracycline inducible system to express either human wildtype TDP-43 (TDP-43WT) or human TDP-43 that cannot enter the nucleus (TDP-43ΔNLS) in excitatory neurons (Camk2α promoter), crossed Thy1-YFPH mice to visualize dendritic spines, the major site of excitatory synapses. In comparison to both TDP-43WT and controls, TDP-43ΔNLS drove a robust loss in spine density in all the dendrite regions of the upper motor neurons, most affecting thin spines. This indicates that TDP-43 is involved in the generation of network dysfunction in ALS likely through impacting the formation or durability of excitatory synapses. These findings are relevant to the vast majority of ALS cases, and provides further evidence that upper motor neurons may need to be protected from TDP-43 mediated synaptic excitatory changes early in disease.
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Affiliation(s)
- Marcus S. Dyer
- Menzies Institute for Medical Research, College Health and Medicine, University of Tasmania, Hobart, TAS 7000, Australia;
| | - Adele Woodhouse
- Wicking Dementia Research and Education Centre, College Health and Medicine, University of Tasmania, Hobart, TAS 7000, Australia;
| | - Catherine A. Blizzard
- Menzies Institute for Medical Research, College Health and Medicine, University of Tasmania, Hobart, TAS 7000, Australia;
- Correspondence:
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14
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Ohbayashi M. The Roles of the Cortical Motor Areas in Sequential Movements. Front Behav Neurosci 2021; 15:640659. [PMID: 34177476 PMCID: PMC8219877 DOI: 10.3389/fnbeh.2021.640659] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 04/19/2021] [Indexed: 11/13/2022] Open
Abstract
The ability to learn and perform a sequence of movements is a key component of voluntary motor behavior. During the learning of sequential movements, individuals go through distinct stages of performance improvement. For instance, sequential movements are initially learned relatively fast and later learned more slowly. Over multiple sessions of repetitive practice, performance of the sequential movements can be further improved to the expert level and maintained as a motor skill. How the brain binds elementary movements together into a meaningful action has been a topic of much interest. Studies in human and non-human primates have shown that a brain-wide distributed network is active during the learning and performance of skilled sequential movements. The current challenge is to identify a unique contribution of each area to the complex process of learning and maintenance of skilled sequential movements. Here, I bring together the recent progress in the field to discuss the distinct roles of cortical motor areas in this process.
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Affiliation(s)
- Machiko Ohbayashi
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.,Systems Neuroscience Center, Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, United States
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15
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Cambiaghi M, Cherchi L, Masin L, Infortuna C, Briski N, Caviasco C, Hazaveh S, Han Z, Buffelli M, Battaglia F. High-frequency repetitive transcranial magnetic stimulation enhances layer II/III morphological dendritic plasticity in mouse primary motor cortex. Behav Brain Res 2021; 410:113352. [PMID: 33979657 DOI: 10.1016/j.bbr.2021.113352] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 04/19/2021] [Accepted: 05/06/2021] [Indexed: 12/31/2022]
Abstract
High-frequency repeated transcranial magnetic stimulation (HF-rTMS) is a safe non-invasive neuromodulatory technique and there is a body of evidence shows that it can modulate plasticity in different brain areas. One of the most interesting application of HF-rTMS is the modulation of plasticity in primary motor cortex (M1) to promote recovery after brain injuries. However, the underlying mechanism by which HF-rTMS modulates motor cortex plasticity remain to be investigated. In this study, we investigated the effects of HF-rTMS treatment on morphological plasticity of pyramidal neurons in layer II/III (L2/3) of the primary motor cortex in mice. Our results show that the treatment did not increase anxiety in mice in the open field test and the elevated plus-maze test. Treated mice displayed increased total spine density in apical and basal dendrites, with a predominance of thin spines. The treatment also increased dendritic complexity, as assessed by Sholl analysis at both apical and basal dendrites. Collectively, the results show that HF-rTMS induced remarkable changes in dendritic complexity in primary motor cortex L2/3 connections which may strengthen corticocortical connections increasing integration of information across cortical areas. The data support the use of HF-rTMS as a circuit-targeting neuromodulation strategy.
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Affiliation(s)
- Marco Cambiaghi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy
| | - Laura Cherchi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy
| | - Laura Masin
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy
| | - Carmenrita Infortuna
- Department of Biomedical Sciences, Dental Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy
| | - Nicholas Briski
- Department of Medical Sciences and Department of Neurology, Hackensack Meridian School of Medicine, Nutley, NJ, 07110, USA
| | - Christina Caviasco
- Department of Medical Sciences and Department of Neurology, Hackensack Meridian School of Medicine, Nutley, NJ, 07110, USA
| | - Sara Hazaveh
- Department of Medical Sciences and Department of Neurology, Hackensack Meridian School of Medicine, Nutley, NJ, 07110, USA
| | - Zhiyong Han
- Department of Medical Sciences and Department of Neurology, Hackensack Meridian School of Medicine, Nutley, NJ, 07110, USA
| | - Mario Buffelli
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy
| | - Fortunato Battaglia
- Department of Medical Sciences and Department of Neurology, Hackensack Meridian School of Medicine, Nutley, NJ, 07110, USA.
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16
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HUZARD D, RAPPENEAU V, MEIJER OC, TOUMA C, ARANGO-LIEVANO M, GARABEDIAN MJ, JEANNETEAU F. Experience and activity-dependent control of glucocorticoid receptors during the stress response in large-scale brain networks. Stress 2021; 24:130-153. [PMID: 32755268 PMCID: PMC7907260 DOI: 10.1080/10253890.2020.1806226] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The diversity of actions of the glucocorticoid stress hormones among individuals and within organs, tissues and cells is shaped by age, gender, genetics, metabolism, and the quantity of exposure. However, such factors cannot explain the heterogeneity of responses in the brain within cells of the same lineage, or similar tissue environment, or in the same individual. Here, we argue that the stress response is continuously updated by synchronized neural activity on large-scale brain networks. This occurs at the molecular, cellular and behavioral levels by crosstalk communication between activity-dependent and glucocorticoid signaling pathways, which updates the diversity of responses based on prior experience. Such a Bayesian process determines adaptation to the demands of the body and external world. We propose a framework for understanding how the diversity of glucocorticoid actions throughout brain networks is essential for supporting optimal health, while its disruption may contribute to the pathophysiology of stress-related disorders, such as major depression, and resistance to therapeutic treatments.
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Affiliation(s)
- Damien HUZARD
- Department of Neuroscience and Physiology, University of Montpellier, CNRS, INSERM, Institut de Génomique Fonctionnelle, Montpellier, France
| | - Virginie RAPPENEAU
- Department of Behavioural Biology, University of Osnabrück, Osnabrück, Germany
| | - Onno C. MEIJER
- Division of Endocrinology, Department of Internal Medicine, Leiden University Medical Center, Leiden University, Leiden, the Netherlands
| | - Chadi TOUMA
- Department of Behavioural Biology, University of Osnabrück, Osnabrück, Germany
| | - Margarita ARANGO-LIEVANO
- Department of Neuroscience and Physiology, University of Montpellier, CNRS, INSERM, Institut de Génomique Fonctionnelle, Montpellier, France
| | | | - Freddy JEANNETEAU
- Department of Neuroscience and Physiology, University of Montpellier, CNRS, INSERM, Institut de Génomique Fonctionnelle, Montpellier, France
- Corresponding author:
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17
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Zhang KX, Zhao JJ, Chai W, Chen JY. Synaptic remodeling in mouse motor cortex after spinal cord injury. Neural Regen Res 2021; 16:744-749. [PMID: 33063737 PMCID: PMC8067930 DOI: 10.4103/1673-5374.295346] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Spinal cord injury dramatically blocks information exchange between the central nervous system and the peripheral nervous system. The resulting fate of synapses in the motor cortex has not been well studied. To explore synaptic reorganization in the motor cortex after spinal cord injury, we established mouse models of T12 spinal cord hemi-section and then monitored the postsynaptic dendritic spines and presynaptic axonal boutons of pyramidal neurons in the hindlimb area of the motor cortex in vivo. Our results showed that spinal cord hemi-section led to the remodeling of dendritic spines bilaterally in the motor cortex and the main remodeling regions changed over time. It made previously stable spines unstable and eliminated spines more unlikely to be re-emerged. There was a significant increase in new spines in the contralateral motor cortex. However, the low survival rate of the new spines demonstrated that new spines were still fragile. Observation of presynaptic axonal boutons found no significant change. These results suggest the existence of synapse remodeling in motor cortex after spinal cord hemi-section and that spinal cord hemi-section affected postsynaptic dendritic spines rather than presynaptic axonal boutons. This study was approved by the Ethics Committee of Chinese PLA General Hospital, China (approval No. 201504168S) on April 16, 2015.
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Affiliation(s)
- Ke-Xue Zhang
- Department of Pediatric Surgery, Chinese PLA General Hospital, Beijing, China
| | - Jia-Jia Zhao
- Department of Anesthesiology, Shunyi District Hospital, Beijing, China
| | - Wei Chai
- Department of Orthopedics, Chinese PLA General Hospital, Beijing, China
| | - Ji-Ying Chen
- Department of Orthopedics, Chinese PLA General Hospital, Beijing, China
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18
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Post-learning micro- and macro-structural neuroplasticity changes with time and sleep. Biochem Pharmacol 2020; 191:114369. [PMID: 33338474 DOI: 10.1016/j.bcp.2020.114369] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 12/18/2022]
Abstract
Neuroplasticity refers to the fact that our brain can partially modify both structure and function to adequately respond to novel environmental stimulations. Neuroplasticity mechanisms are not only operating during the acquisition of novel information (i.e., online) but also during the offline periods that take place after the end of the actual learning episode. Structural brain changes as a consequence of learning have been consistently demonstrated on the long term using non-invasive neuroimaging methods, but short-term changes remained more elusive. Fortunately, the swift development of advanced MR methods over the last decade now allows tracking fine-grained cerebral changes on short timescales beyond gross volumetric modifications stretching over several days or weeks. Besides a mere effect of time, post-learning sleep mechanisms have been shown to play an important role in memory consolidation and promote long-lasting changes in neural networks. Sleep was shown to contribute to structural modifications over weeks of prolonged training, but studies evidencing more rapid post-training sleep structural effects linked to memory consolidation are still scarce in human. On the other hand, animal studies convincingly show how sleep might modulate synaptic microstructure. We aim here at reviewing the literature establishing a link between different types of training/learning and the resulting structural changes, with an emphasis on the role of post-training sleep and time in tuning these modifications. Open questions are raised such as the role of post-learning sleep in macrostructural changes, the links between different MR structural measurement-related modifications and the underlying microstructural brain processes, and bidirectional influences between structural and functional brain changes.
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19
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Katrancha SM, Shaw JE, Zhao AY, Myers SA, Cocco AR, Jeng AT, Zhu M, Pittenger C, Greer CA, Carr SA, Xiao X, Koleske AJ. Trio Haploinsufficiency Causes Neurodevelopmental Disease-Associated Deficits. Cell Rep 2020; 26:2805-2817.e9. [PMID: 30840899 PMCID: PMC6436967 DOI: 10.1016/j.celrep.2019.02.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 12/22/2018] [Accepted: 02/06/2019] [Indexed: 12/31/2022] Open
Abstract
Heterozygous coding mutations in TRIO are associated with neurodevelopmental disorders, including autism, schizophrenia, bipolar disorder, and epilepsy, and impair TRIO's biochemical activities. To model mutant alleles, we ablated one or both Trio alleles from excitatory neurons in the cortex and hippocampus of mice. Trio haploinsufficiency increases anxiety and impairs social preference and motor coordination. Trio loss reduces forebrain size and dendritic arborization but increases dendritic spine densities. Cortical synapses in Trio haploinsufficient mice are small, exhibit pre- and postsynaptic deficits, and cannot undergo long-term potentiation. Similar phenotypes are observed in Trio knockout mice. Overall, Trio haploinsufficiency causes severe disease-relevant deficits in behavior and neuronal structure and function. Interestingly, phosphodiesterase 4A5 (PDE4A5) levels are reduced and protein kinase A (PKA) signaling is increased when TRIO levels are reduced. Elevation of PDE4A5 and drug-based attenuation of PKA signaling rescue Trio haploinsufficiency-related dendritic spine defects, suggesting an avenue for therapeutic intervention for TRIO-related neurodevelopmental disorders.
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Affiliation(s)
- Sara Marie Katrancha
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA; Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06510, USA; Department of Neuroscience, Yale University, New Haven, CT 06510, USA
| | - Juliana E Shaw
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Amy Y Zhao
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA; Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06510, USA; Department of Neuroscience, Yale University, New Haven, CT 06510, USA
| | - Samuel A Myers
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Amanda T Jeng
- Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06510, USA
| | - Minsheng Zhu
- Model Animal Research Center, Nanjing University, Nanjing 210061, China
| | - Christopher Pittenger
- Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06510, USA; Department of Psychiatry, Yale University, New Haven, CT 06510, USA; Child Study Center, Yale University, New Haven, CT 06510, USA
| | - Charles A Greer
- Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06510, USA; Department of Neuroscience, Yale University, New Haven, CT 06510, USA; Department of Neurosurgery, Yale University, New Haven, CT 06510, USA
| | - Steven A Carr
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Xiao Xiao
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai 200433, China; Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence (Fudan University), Ministry of Education, Shanghai 200433, China.
| | - Anthony J Koleske
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA; Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06510, USA; Department of Neuroscience, Yale University, New Haven, CT 06510, USA.
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20
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Roth RH, Cudmore RH, Tan HL, Hong I, Zhang Y, Huganir RL. Cortical Synaptic AMPA Receptor Plasticity during Motor Learning. Neuron 2019; 105:895-908.e5. [PMID: 31901303 DOI: 10.1016/j.neuron.2019.12.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 10/30/2019] [Accepted: 12/04/2019] [Indexed: 02/04/2023]
Abstract
Modulation of synaptic strength through trafficking of AMPA receptors (AMPARs) is a fundamental mechanism underlying synaptic plasticity, learning, and memory. However, the dynamics of AMPAR trafficking in vivo and its correlation with learning have not been resolved. Here, we used in vivo two-photon microscopy to visualize surface AMPARs in mouse cortex during the acquisition of a forelimb reaching task. Daily training leads to an increase in AMPAR levels at a subset of spatially clustered dendritic spines in the motor cortex. Surprisingly, we also observed increases in spine AMPAR levels in the visual cortex. There, synaptic potentiation depends on the availability of visual input during motor training, and optogenetic inhibition of visual cortex activity impairs task performance. These results indicate that motor learning induces widespread cortical synaptic potentiation by increasing the net trafficking of AMPARs into spines, including in non-motor brain regions.
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Affiliation(s)
- Richard H Roth
- Solomon H. Snyder Department of Neuroscience and Kavli Neuroscience Discovery Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Robert H Cudmore
- Department of Physiology and Membrane Biology, University of California School of Medicine, Davis, CA 95616, USA
| | - Han L Tan
- Solomon H. Snyder Department of Neuroscience and Kavli Neuroscience Discovery Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ingie Hong
- Solomon H. Snyder Department of Neuroscience and Kavli Neuroscience Discovery Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Yong Zhang
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Key Lab for Neuroscience, Ministry of Education of China and National Health Commission of the P.R. China, IDG/McGovern Institute for Brain Research at PKU, Peking University, Beijing 100191, China
| | - Richard L Huganir
- Solomon H. Snyder Department of Neuroscience and Kavli Neuroscience Discovery Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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21
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Zhang H, Kuang H, Luo Y, Liu S, Meng L, Pang Q, Fan R. Low-dose bisphenol A exposure impairs learning and memory ability with alterations of neuromorphology and neurotransmitters in rats. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 697:134036. [PMID: 31476513 DOI: 10.1016/j.scitotenv.2019.134036] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/20/2019] [Accepted: 08/20/2019] [Indexed: 06/10/2023]
Abstract
To investigate the developmental neurotoxicity of environmental bisphenol A (BPA) exposure for infants and children, postnatal rats were used as the animal model and were divided into four groups. Then, they were treated with different concentrations of BPA (i.e., 0, 0.5, 50, or 5000 μg/kg·bw/day of BPA as the control, low-, medium- and high-exposed group) from postnatal days 7 to 21. Y-maze tests, Golgi-Cox assays and liquid chromatography-tandem mass spectrometry (LC/MS/MS) were performed to test the changes of learning and memory ability, hippocampal neuromorphology and neurotransmitter levels, respectively. The results showed that the BPA-exposed rats, especially the low- and high-exposed rats, needed more trials and longer times to qualify for the learned criterion than the control rats. Additionally, rats after low- or high-exposure to BPA exhibited decreased DG dendritic complexity and reduced CA1 and DG dendritic spine densities in the hippocampus. Low-dosage BPA treatment could significantly alter the neurotransmitter contents in the hippocampus. In male rats, the levels of glutamic acid (Glu) and acetylcholine increased, while the 5-hydroxytryptamine (5-HT) and γ-aminobutyric acid (GABA) levels decreased, which lead to an unbalanced Glu/GABA ratio. However, in female rats, only 5-HT levels decreased. In conclusion, postnatal exposure to BPA could sex- and dose-dependently disrupt dendritic development and neurotransmitter homeostasis in the rat hippocampus. The impaired spatial learning and memory ability of rats induced by low-dose BPA is associated with both disrupted dendritic development and neurotransmitter homeostasis in the hippocampus.
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Affiliation(s)
- Haibin Zhang
- Guangdong Provincial Engineering Technology Research Center for Drug and Food Biological Resources Processing and Comprehensive Utilization, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Hongxuan Kuang
- Guangdong Provincial Engineering Technology Research Center for Drug and Food Biological Resources Processing and Comprehensive Utilization, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Yifan Luo
- Guangdong Provincial Engineering Technology Research Center for Drug and Food Biological Resources Processing and Comprehensive Utilization, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Shuhua Liu
- Guangdong Provincial Engineering Technology Research Center for Drug and Food Biological Resources Processing and Comprehensive Utilization, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Lingxue Meng
- Guangdong Provincial Engineering Technology Research Center for Drug and Food Biological Resources Processing and Comprehensive Utilization, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Qihua Pang
- Guangdong Provincial Engineering Technology Research Center for Drug and Food Biological Resources Processing and Comprehensive Utilization, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Ruifang Fan
- Guangdong Provincial Engineering Technology Research Center for Drug and Food Biological Resources Processing and Comprehensive Utilization, School of Life Sciences, South China Normal University, Guangzhou 510631, China.
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22
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Gal C, Gabitov E, Maaravi-Hesseg R, Karni A, Korman M. A Delayed Advantage: Multi-Session Training at Evening Hours Leads to Better Long-Term Retention of Motor Skill in the Elderly. Front Aging Neurosci 2019; 11:321. [PMID: 31824300 PMCID: PMC6882744 DOI: 10.3389/fnagi.2019.00321] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 11/05/2019] [Indexed: 12/17/2022] Open
Abstract
The acquisition and retention of motor skills is necessary for everyday functioning in the elderly and may be critical in the context of motor rehabilitation. Recent studies indicate that motor training closely followed by sleep may result in better engagement of procedural (“how to”) memory consolidation processes in the elderly. Nevertheless, elderly individuals are mostly morning oriented and a common practice is to time rehabilitation programs to morning hours. Here, we tested whether the time-of-day wherein training is afforded (morning, 8–10:30 a.m., or evening, 6–9 p.m.) affects the long-term outcome of a multi-session motor practice program (10 sessions across 3–4 weeks) in healthy elderly participants. Twenty-nine (15 women) older adults (60–75 years) practiced an explicitly instructed five-element key-press sequence by repeatedly generating the sequence “as fast and accurately as possible.” The groups did not differ in terms of sleep habits and quality (1-week long actigraphy); all were morning-oriented individuals. All participants gained robustly from the intervention, shortening sequence tapping duration and retaining the gains (> 90%) at 1-month post-intervention, irrespective of the time-of-day of training. However, retesting at 7-months post-intervention showed that the attrition of the training induced gains was more pronounced in the morning trained group compared to the evening group (76 and 56.5% loss in sequence tapping time; 7/14 and 3/14 participants showed a > 5% decline in accuracy relative to end of training, respectively). Altogether, the results show that morning-oriented older adults effectively acquired skill in the performance of a sequence of finger movements, in both morning and evening practice sessions. However, evening training leads to a significant advantage, over morning training, in the long-term retention of the skill. Evening training should be considered an appropriate time window for motor skill learning in older adults, even in individuals with morning chronotype. The results are in line with the notion that motor training preceding a sleep interval may be better consolidated into long-term memory in the elderly, and thus result in lower forgetting rates.
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Affiliation(s)
- Carmit Gal
- The Edmond J. Safra Brain Research Center for the Study of Learning Disabilities, University of Haifa, Haifa, Israel.,Laboratory for Human Brain and Learning, Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Ella Gabitov
- McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Rinatia Maaravi-Hesseg
- The Edmond J. Safra Brain Research Center for the Study of Learning Disabilities, University of Haifa, Haifa, Israel.,Laboratory for Human Brain and Learning, Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Avi Karni
- The Edmond J. Safra Brain Research Center for the Study of Learning Disabilities, University of Haifa, Haifa, Israel.,Laboratory for Human Brain and Learning, Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Maria Korman
- The Edmond J. Safra Brain Research Center for the Study of Learning Disabilities, University of Haifa, Haifa, Israel
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23
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Minkeviciene R, Hlushchenko I, Virenque A, Lahti L, Khanal P, Rauramaa T, Koistinen A, Leinonen V, Noe FM, Hotulainen P. MIM-Deficient Mice Exhibit Anatomical Changes in Dendritic Spines, Cortex Volume and Brain Ventricles, and Functional Changes in Motor Coordination and Learning. Front Mol Neurosci 2019; 12:276. [PMID: 31803019 PMCID: PMC6872969 DOI: 10.3389/fnmol.2019.00276] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 10/29/2019] [Indexed: 11/13/2022] Open
Abstract
In this study, we performed a comprehensive behavioral and anatomical analysis of the Missing in Metastasis (Mtss1/MIM) knockout (KO) mouse brain. We also analyzed the expression of MIM in different brain regions at different ages. MIM is an I-BAR containing membrane curving protein, shown to be involved in dendritic spine initiation and dendritic branching in Purkinje cells in the cerebellum. Behavioral analysis of MIM KO mice revealed defects in both learning and reverse-learning, alterations in anxiety levels and reduced dominant behavior, and confirmed the previously described deficiency in motor coordination and pre-pulse inhibition. Anatomically, we observed enlarged brain ventricles and decreased cortical volume. Although MIM expression was relatively low in hippocampus after early development, hippocampal pyramidal neurons exhibited reduced density of thin and stubby dendritic spines. Learning deficiencies can be connected to all detected anatomical changes. Both behavioral and anatomical findings are typical for schizophrenia mouse models.
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Affiliation(s)
| | - Iryna Hlushchenko
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Anaïs Virenque
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
- HiLIFE - Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Lauri Lahti
- Department of Computer Science, Aalto University School of Science, Espoo, Finland
| | - Pushpa Khanal
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
- HiLIFE - Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Tuomas Rauramaa
- Department of Clinical Pathology, Kuopio University Hospital, University of Eastern Finland, Kuopio, Finland
| | - Arto Koistinen
- SIB Labs Infrastructure Unit, University of Eastern Finland, Kuopio, Finland
| | - Ville Leinonen
- Neurosurgery of NeuroCenter, Kuopio University Hospital, University of Eastern Finland (UEF), Kuopio, Finland
- Research Unit of Clinical Neuroscience, University of Oulu, Oulu, Finland
- Department of Neurosurgery, MRC Oulu, Oulu University Hospital, Oulu, Finland
| | - Francesco M. Noe
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
- HiLIFE - Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Pirta Hotulainen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
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Rehabilitative Training Interacts with Ischemia-Instigated Spine Dynamics to Promote a Lasting Population of New Synapses in Peri-Infarct Motor Cortex. J Neurosci 2019; 39:8471-8483. [PMID: 31511430 DOI: 10.1523/jneurosci.1141-19.2019] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 08/23/2019] [Accepted: 09/02/2019] [Indexed: 11/21/2022] Open
Abstract
After subtotal infarcts of primary motor cortex (M1), motor rehabilitative training (RT) promotes improvements in paretic forelimb function that have been linked with its promotion of structural and functional reorganization of peri-infarct cortex, but how the reorganization unfolds is scantly understood. Cortical infarcts also instigate a prolonged period of dendritic spine turnover in peri-infarct cortex. Here we investigated the possibility that synaptic structural responses to RT in peri-infarct cortex reflect, in part, interactions with ischemia-instigated spine turnover. This was tested after artery-targeted photothrombotic M1 infarcts or Sham procedures in adult (4 months) C57BL/6 male and female GFP-M line (n = 24) and male yellow fluorescent protein-H line (n = 5) mice undergoing RT in skilled reaching or no-training control procedures. Regardless of training condition, spine turnover was increased out to 5 weeks postinfarct relative to Sham, as was the persistence of new spines formed within a week postinfarct. However, compared with no-training controls, new spines formed during postinfarct weeks 2-4 in mice undergoing RT persisted in much greater proportions to later time points, by a magnitude that predicted behavioral improvements in the RT group. These results indicate that RT interacts with ischemia-instigated spine turnover to promote preferential stabilization of newly formed spines, which is likely to yield a new population of mature synapses in peri-infarct cortex that could contribute to cortical functional reorganization and behavioral improvement. The findings newly implicate ischemia-instigated spine turnover as a mediator of cortical synaptic structural responses to RT and newly establish the experience dependency of new spine fates in the postischemic turnover context.SIGNIFICANCE STATEMENT Motor rehabilitation, the main treatment for motor impairments after stroke, is far from sufficient to normalize function. A better understanding of neural substrates of rehabilitation-induced behavioral improvements could be useful for understanding how to optimize it. Here, we investigated the nature and time course of synaptic responses to motor rehabilitative training in vivo Focal ischemia instigated a period of synapse turnover in peri-infarct motor cortex of mice. Rehabilitative training increased the stability of new synapses formed during the initial weeks after the infarct, the magnitude of which was correlated with improvements in skilled motor performance. Therefore, the maintenance of new synapses formed after ischemia could represent a structural mechanism of rehabilitative training efficacy.
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25
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Ko HG, Choi JH, Park DI, Kang SJ, Lim CS, Sim SE, Shim J, Kim JI, Kim S, Choi TH, Ye S, Lee J, Park P, Kim S, Do J, Park J, Islam MA, Kim HJ, Turck CW, Collingridge GL, Zhuo M, Kaang BK. Rapid Turnover of Cortical NCAM1 Regulates Synaptic Reorganization after Peripheral Nerve Injury. Cell Rep 2019; 22:748-759. [PMID: 29346771 DOI: 10.1016/j.celrep.2017.12.059] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 11/27/2017] [Accepted: 12/17/2017] [Indexed: 11/24/2022] Open
Abstract
Peripheral nerve injury can induce pathological conditions that lead to persistent sensitized nociception. Although there is evidence that plastic changes in the cortex contribute to this process, the underlying molecular mechanisms are unclear. Here, we find that activation of the anterior cingulate cortex (ACC) induced by peripheral nerve injury increases the turnover of specific synaptic proteins in a persistent manner. We demonstrate that neural cell adhesion molecule 1 (NCAM1) is one of the molecules involved and show that it mediates spine reorganization and contributes to the behavioral sensitization. We show striking parallels in the underlying mechanism with the maintenance of NMDA-receptor- and protein-synthesis-dependent long-term potentiation (LTP) in the ACC. Our results, therefore, demonstrate a synaptic mechanism for cortical reorganization and suggest potential avenues for neuropathic pain treatment.
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Affiliation(s)
- Hyoung-Gon Ko
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea; Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Jun-Hyeok Choi
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Dong Ik Park
- Max Planck Institute of Psychiatry, Department of Translational Research in Psychiatry, Kraepelinstr. 2, 80804 Munich, Germany
| | - SukJae Joshua Kang
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Chae-Seok Lim
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Su-Eon Sim
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Jaehoon Shim
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Ji-Il Kim
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Siyong Kim
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Tae-Hyeok Choi
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Sanghyun Ye
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Jaehyun Lee
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Pojeong Park
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Somi Kim
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Jeehaeh Do
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Jihye Park
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Md Ariful Islam
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea
| | - Hyun Jeong Kim
- Department of Dental Anesthesiology and Dental Research Institute, School of Dentistry, Seoul National University, Seoul 03080, South Korea
| | - Christoph W Turck
- Max Planck Institute of Psychiatry, Department of Translational Research in Psychiatry, Kraepelinstr. 2, 80804 Munich, Germany
| | - Graham L Collingridge
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol BS8 1TD, UK; Department of Physiology, Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada; Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada.
| | - Min Zhuo
- Department of Physiology, Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada; Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Bong-Kiun Kaang
- School of Biological Sciences, Seoul National University, 1 Gwanangno, Gwanak-gu, Seoul 08826, South Korea; Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China.
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26
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Chidambaram SB, Rathipriya AG, Bolla SR, Bhat A, Ray B, Mahalakshmi AM, Manivasagam T, Thenmozhi AJ, Essa MM, Guillemin GJ, Chandra R, Sakharkar MK. Dendritic spines: Revisiting the physiological role. Prog Neuropsychopharmacol Biol Psychiatry 2019; 92:161-193. [PMID: 30654089 DOI: 10.1016/j.pnpbp.2019.01.005] [Citation(s) in RCA: 150] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 01/04/2019] [Accepted: 01/12/2019] [Indexed: 12/11/2022]
Abstract
Dendritic spines are small, thin, specialized protrusions from neuronal dendrites, primarily localized in the excitatory synapses. Sophisticated imaging techniques revealed that dendritic spines are complex structures consisting of a dense network of cytoskeletal, transmembrane and scaffolding molecules, and numerous surface receptors. Molecular signaling pathways, mainly Rho and Ras family small GTPases pathways that converge on actin cytoskeleton, regulate the spine morphology and dynamics bi-directionally during synaptic activity. During synaptic plasticity the number and shapes of dendritic spines undergo radical reorganizations. Long-term potentiation (LTP) induction promote spine head enlargement and the formation and stabilization of new spines. Long-term depression (LTD) results in their shrinkage and retraction. Reports indicate increased spine density in the pyramidal neurons of autism and Fragile X syndrome patients and reduced density in the temporal gyrus loci of schizophrenic patients. Post-mortem reports of Alzheimer's brains showed reduced spine number in the hippocampus and cortex. This review highlights the spine morphogenesis process, the activity-dependent structural plasticity and mechanisms by which synaptic activity sculpts the dendritic spines, the structural and functional changes in spines during learning and memory using LTP and LTD processes. It also discusses on spine status in neurodegenerative diseases and the impact of nootropics and neuroprotective agents on the functional restoration of dendritic spines.
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Affiliation(s)
- Saravana Babu Chidambaram
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India.
| | - A G Rathipriya
- Food and Brain Research Foundation, Chennai, Tamil Nadu, India
| | - Srinivasa Rao Bolla
- Department of Anatomy, College of Medicine, Imam Abdulrahman Bin Faisal University, Damam, Saudi Arabia
| | - Abid Bhat
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India
| | - Bipul Ray
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India
| | - Arehally Marappa Mahalakshmi
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSSAHER), Mysuru, Karnataka 570015, India
| | - Thamilarasan Manivasagam
- Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalainagar, Tamilnadu, India
| | - Arokiasamy Justin Thenmozhi
- Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalainagar, Tamilnadu, India
| | - Musthafa Mohamed Essa
- Department of Food Science and Nutrition, CAMS, Sultan Qaboos University, Muscat, Oman
| | - Gilles J Guillemin
- Neuropharmacology Group, Faculty of Medicine and Health Sciences, Deb Bailey MND Research Laboratory, Macquarie University, Sydney, NSW 2109, Australia
| | - Ramesh Chandra
- Department of Chemistry, Ambedkar Centre for BioMedical Research, Delhi University, Delhi 110007, India
| | - Meena Kishore Sakharkar
- College of Pharmacy and Nutrition, University of Saskatchewan, 107, Wiggins Road, Saskatoon, SK S7N 5C9, Canada.
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27
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Vellema M, Diales Rocha M, Bascones S, Zsebők S, Dreier J, Leitner S, Van der Linden A, Brewer J, Gahr M. Accelerated redevelopment of vocal skills is preceded by lasting reorganization of the song motor circuitry. eLife 2019; 8:43194. [PMID: 31099755 PMCID: PMC6570526 DOI: 10.7554/elife.43194] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 05/16/2019] [Indexed: 01/16/2023] Open
Abstract
Complex motor skills take considerable time and practice to learn. Without continued practice the level of skill performance quickly degrades, posing a problem for the timely utilization of skilled motor behaviors. Here we quantified the recurring development of vocal motor skills and the accompanying changes in synaptic connectivity in the brain of a songbird, while manipulating skill performance by consecutively administrating and withdrawing testosterone. We demonstrate that a songbird with prior singing experience can significantly accelerate the re-acquisition of vocal performance. We further demonstrate that an increase in vocal performance is accompanied by a pronounced synaptic pruning in the forebrain vocal motor area HVC, a reduction that is not reversed when birds stop singing. These results provide evidence that lasting synaptic changes in the motor circuitry are associated with the savings of motor skills, enabling a rapid recovery of motor performance under environmental time constraints.
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Affiliation(s)
- Michiel Vellema
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany.,Bio Imaging Lab, University of Antwerp, Antwerp, Belgium
| | - Mariana Diales Rocha
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany
| | - Sabrina Bascones
- Program for Inflammatory and Cardiovascular Disorders, Institut Hospital del Mar d'Investigacions Mèdiques, Barcelona, Spain
| | - Sándor Zsebők
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary
| | - Jes Dreier
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Stefan Leitner
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany
| | | | - Jonathan Brewer
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Manfred Gahr
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany
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28
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Nakamura K, Moorhouse AJ, Cheung DL, Eto K, Takeda I, Rozenbroek PW, Nabekura J. Overexpression of neuronal K +-Cl - co-transporter enhances dendritic spine plasticity and motor learning. J Physiol Sci 2019; 69:453-463. [PMID: 30758780 PMCID: PMC10717839 DOI: 10.1007/s12576-018-00654-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 12/17/2018] [Indexed: 11/30/2022]
Abstract
The neuronal K+-Cl- cotransporter KCC2 maintains a low intracellular Cl- concentration and facilitates hyperpolarizing GABAA receptor responses. KCC2 also plays a separate role in stabilizing and enhancing dendritic spines in the developing nervous system. Using a conditional transgenic mouse strategy, we examined whether overexpression of KCC2 enhances dendritic spines in the adult nervous system and characterized the effects on spine dynamics in the motor cortex in vivo during rotarod training. Mice overexpressing KCC2 showed significantly increased spine density in the apical dendrites of layer V pyramidal neurons, measured in vivo using two-photon imaging. During modest accelerated rotarod training, mice overexpressing KCC2 displayed enhanced spine formation rates, greater balancing skill at higher rotarod speeds and a faster rate of learning in this ability. Our results demonstrate that KCC2 enhances spine density and dynamics in the adult nervous system and suggest that KCC2 may play a role in experience-dependent synaptic plasticity.
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Affiliation(s)
- Kayo Nakamura
- Division of Homeostatic Development, Department of Fundamental Neuroscience, National Institutes for Physiological Sciences, Okazaki, 444-8585, Japan
- Department of Physiological Sciences, Sokendai, Hayama, 240-0193, Japan
| | - Andrew John Moorhouse
- Department of Physiology, School of Medical Sciences, University of New South Wales, Sydney, 2052, Australia
| | - Dennis Lawrence Cheung
- Department of Physiology, School of Medical Sciences, University of New South Wales, Sydney, 2052, Australia
| | - Kei Eto
- Division of Homeostatic Development, Department of Fundamental Neuroscience, National Institutes for Physiological Sciences, Okazaki, 444-8585, Japan
| | - Ikuko Takeda
- Division of Homeostatic Development, Department of Fundamental Neuroscience, National Institutes for Physiological Sciences, Okazaki, 444-8585, Japan
| | - Paul Wiers Rozenbroek
- Department of Physiology, School of Medical Sciences, University of New South Wales, Sydney, 2052, Australia
| | - Junichi Nabekura
- Division of Homeostatic Development, Department of Fundamental Neuroscience, National Institutes for Physiological Sciences, Okazaki, 444-8585, Japan.
- Department of Physiological Sciences, Sokendai, Hayama, 240-0193, Japan.
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29
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Li J, Park E, Zhong LR, Chen L. Homeostatic synaptic plasticity as a metaplasticity mechanism - a molecular and cellular perspective. Curr Opin Neurobiol 2019; 54:44-53. [PMID: 30212714 PMCID: PMC6361678 DOI: 10.1016/j.conb.2018.08.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 08/16/2018] [Accepted: 08/20/2018] [Indexed: 01/08/2023]
Abstract
The molecular mechanisms underlying various types of synaptic plasticity are historically regarded as separate processes involved in independent cellular events. However, recent progress in our molecular understanding of Hebbian and homeostatic synaptic plasticity supports the observation that these two types of plasticity share common cellular events, and are often altered together in neurological diseases. Here, we discuss the emerging concept of homeostatic synaptic plasticity as a metaplasticity mechanism with a focus on cellular signaling processes that enable a direct interaction between Hebbian and homeostatic plasticity. We also identify distinct and shared molecular players involved in these cellular processes that may be explored experimentally in future studies to test the hypothesis that homeostatic synaptic plasticity serves as a metaplasticity mechanism to integrate changes in neuronal activity and support optimal Hebbian learning.
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Affiliation(s)
- Jie Li
- Department of Neurosurgery, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA; Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA
| | - Esther Park
- Department of Neurosurgery, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA; Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA
| | - Lei R Zhong
- Department of Neurosurgery, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA; Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA
| | - Lu Chen
- Department of Neurosurgery, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA; Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA.
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30
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Gao PP, Goodman JH, Sacktor TC, Francis JT. Persistent Increases of PKMζ in Sensorimotor Cortex Maintain Procedural Long-Term Memory Storage. iScience 2018; 5:90-98. [PMID: 30240648 PMCID: PMC6123865 DOI: 10.1016/j.isci.2018.07.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/05/2018] [Accepted: 07/03/2018] [Indexed: 01/11/2023] Open
Abstract
Procedural motor learning and memory are accompanied by changes in synaptic plasticity, neural dynamics, and synaptogenesis. Missing is information on the spatiotemporal dynamics of the molecular machinery maintaining these changes. Here we examine whether persistent increases in PKMζ, an atypical protein kinase C (PKC) isoform, store long-term memory for a reaching task in rat sensorimotor cortex that could reveal the sites of procedural memory storage. Specifically, perturbing PKMζ synthesis (via antisense oligodeoxynucleotides) and blocking atypical PKC activity (via zeta inhibitory peptide [ZIP]) in S1/M1 disrupts and erases long-term motor memory maintenance, indicating atypical PKCs and specifically PKMζ store consolidated long-term procedural memories. Immunostaining reveals that PKMζ increases in S1/M1 layers II/III and V as performance improved to an asymptote. After storage for 1 month without reinforcement, the increase in M1 layer V persists without decrement. Thus, the persistent increases in PKMζ that store long-term procedural memory are localized to the descending output layer of the primary motor cortex. Perturbing PKMζ synthesis in S1/M1 slows the formation of skilled motor memory Blocking PKMζ activity specifically erases memories maintained without reinforcement Skilled motor learning induces the increase of PKMζ in S1/M1 layers II/III and V PKMζ sustains the engram for procedural motor memory in M1 layer V
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Affiliation(s)
- Peng Penny Gao
- Department of Physiology and Pharmacology, The Robert F. Furchgott Center for Neural and Behavioral Science, State University of New York Downstate Medical Center, Brooklyn, NY 11203, USA
| | - Jeffrey H Goodman
- Department of Physiology and Pharmacology, The Robert F. Furchgott Center for Neural and Behavioral Science, State University of New York Downstate Medical Center, Brooklyn, NY 11203, USA; Department of Developmental Neurobiology, New York State Institute for Basic Research, Staten Island, NY 10314, USA; Department of Neurology, State University of New York Downstate Medical Center, Brooklyn, NY 11203, USA
| | - Todd Charlton Sacktor
- Department of Physiology and Pharmacology, The Robert F. Furchgott Center for Neural and Behavioral Science, State University of New York Downstate Medical Center, Brooklyn, NY 11203, USA; Department of Anesthesiology, State University of New York Downstate Medical Center, Brooklyn, NY 11203, USA; Department of Neurology, State University of New York Downstate Medical Center, Brooklyn, NY 11203, USA.
| | - Joseph Thachil Francis
- Department of Physiology and Pharmacology, The Robert F. Furchgott Center for Neural and Behavioral Science, State University of New York Downstate Medical Center, Brooklyn, NY 11203, USA; Department of Biomedical Engineering, Cullen College of Engineering, University of Houston, Houston, TX 77204, USA.
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31
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Driven to decay: Excitability and synaptic abnormalities in amyotrophic lateral sclerosis. Brain Res Bull 2018; 140:318-333. [PMID: 29870780 DOI: 10.1016/j.brainresbull.2018.05.023] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 05/26/2018] [Accepted: 05/31/2018] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is the most common motor neuron (MN) disease and is clinically characterised by the death of corticospinal motor neurons (CSMNs), spinal and brainstem MNs and the degeneration of the corticospinal tract. Degeneration of CSMNs and MNs leads inexorably to muscle wastage and weakness, progressing to eventual death within 3-5 years of diagnosis. The CSMNs, located within layer V of the primary motor cortex, project axons constituting the corticospinal tract, forming synaptic connections with brainstem and spinal cord interneurons and MNs. Clinical ALS may be divided into familial (∼10% of cases) or sporadic (∼90% of cases), based on apparent random incidence. The emergence of transgenic murine models, expressing different ALS-associated mutations has accelerated our understanding of ALS pathogenesis, although precise mechanisms remain elusive. Multiple avenues of investigation suggest that cortical electrical abnormalities have pre-eminence in the pathophysiology of ALS. In addition, glutamate-mediated functional and structural alterations in both CSMNs and MNs are present in both sporadic and familial forms of ALS. This review aims to promulgate debate in the field with regard to the common aetiology of sporadic and familial ALS. A specific focus on a nexus point in ALS pathogenesis, namely, the synaptic and intrinsic hyperexcitability of CSMNs and MNs and alterations to their structure are comprehensively detailed. The association of extramotor dysfunction with neuronal structural/functional alterations will be discussed. Finally, the implications of the latest research on the dying-forward and dying-back controversy are considered.
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32
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Zhang P, Xu R, Guo Y, Qin J, Dai Y, Liu N, Wu C. DL-3-n-butylphthalide promotes dendrite development in cortical neurons subjected to oxygen-glucose deprivation/reperfusion. Cell Biol Int 2018; 42:1041-1049. [PMID: 29696738 DOI: 10.1002/cbin.10980] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 04/21/2018] [Indexed: 12/17/2022]
Affiliation(s)
- Peng Zhang
- Affiliated Bayi Brain Hospital; The PLA Army General Hospital; Beijing 100700 China
| | - Ruxiang Xu
- Affiliated Bayi Brain Hospital; The PLA Army General Hospital; Beijing 100700 China
| | - Yang Guo
- Department of Neurology; Zhujiang Hospital; Guangzhou 510282 China
| | - Jiazhen Qin
- Affiliated Bayi Brain Hospital; The PLA Army General Hospital; Beijing 100700 China
| | - Yiwu Dai
- Affiliated Bayi Brain Hospital; The PLA Army General Hospital; Beijing 100700 China
| | - Ning Liu
- Affiliated Bayi Brain Hospital; The PLA Army General Hospital; Beijing 100700 China
| | - Cuiying Wu
- Affiliated Bayi Brain Hospital; The PLA Army General Hospital; Beijing 100700 China
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33
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Sternad D. It's Not (Only) the Mean that Matters: Variability, Noise and Exploration in Skill Learning. Curr Opin Behav Sci 2018; 20:183-195. [PMID: 30035207 DOI: 10.1016/j.cobeha.2018.01.004] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Mastering a motor skill is typified by a decrease in variability. However, variability is much more than the undesired signature of discoordination: structure in both its distributional properties and temporal sequence can reveal control priorities. Extending from the notion that signal-dependent noise corrupts information transmission in the neuromotor system, this review tracks more recent recognitions that the complex dynamic motor system in its interaction with task constraints creates high-dimensional spaces with multiple equivalent solutions. Further analysis differentiates these solutions to have different degrees of noise-sensitivity, goal-relevance or additional costs. Practice proceeds from exploration of these solution spaces to then exploitation with further channeling of noise. Extended practice leads to fine-tuning of skill brought about by reducing noise. These distinct changes in variability are suggested as a way to characterize stages of learning. Capitalizing on the sensitivity of the CNS to noise, interventions can add extrinsic or amplify intrinsic noise to guide (re-)learning desired behaviors. The persistence and generalization of acquired skill is still largely understudied, although an essential element of skill. Consistent with advances in the physical sciences, there is increasing realization that noise can have beneficial effects. Analysis of the non-random structure of variability may reveal more than analysis of only its mean.
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Affiliation(s)
- Dagmar Sternad
- Department of Biology, Electrical and Computer Engineering and Physics, Center for the Interdisciplinary Study of Complex Systems, Northeastern University, Boston, MA
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34
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Zhou X, Fu X, Lin C, Zhou X, Liu J, Wang L, Zhang X, Zuo M, Fan X, Li D, Sun Y. Remodeling of Dendritic Spines in the Avian Vocal Motor Cortex Following Deafening Depends on the Basal Ganglia Circuit. Cereb Cortex 2018; 27:2820-2830. [PMID: 27166173 DOI: 10.1093/cercor/bhw130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Deafening elicits a deterioration of learned vocalization, in both humans and songbirds. In songbirds, learned vocal plasticity has been shown to depend on the basal ganglia-cortical circuit, but the underlying cellular basis remains to be clarified. Using confocal imaging and electron microscopy, we examined the effect of deafening on dendritic spines in avian vocal motor cortex, the robust nucleus of the arcopallium (RA), and investigated the role of the basal ganglia circuit in motor cortex plasticity. We found rapid structural changes to RA dendritic spines in response to hearing loss, accompanied by learned song degradation. In particular, the morphological characters of RA spine synaptic contacts between 2 major pathways were altered differently. However, experimental disruption of the basal ganglia circuit, through lesions in song-specialized basal ganglia nucleus Area X, largely prevented both the observed changes to RA dendritic spines and the song deterioration after hearing loss. Our results provide cellular evidence to highlight a key role of the basal ganglia circuit in the motor cortical plasticity that underlies learned vocal plasticity.
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Affiliation(s)
- Xin Zhou
- Beijing Key Laboratory of Gene Resource and Molecular Development, Laboratory of Neuroscience and Brain Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Xin Fu
- Beijing Key Laboratory of Gene Resource and Molecular Development, Laboratory of Neuroscience and Brain Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Chun Lin
- Department of Biology, Hainan Normal University, Haikou 571158, China
| | - Xiaojuan Zhou
- Beijing Key Laboratory of Gene Resource and Molecular Development, Laboratory of Neuroscience and Brain Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Jin Liu
- Beijing Key Laboratory of Gene Resource and Molecular Development, Laboratory of Neuroscience and Brain Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Li Wang
- Center for Biological Imaging (CBI), Institute of Biophysics, Chinese Academy of Science, Beijing 100101, China
| | - Xinwen Zhang
- Department of Biology, Hainan Normal University, Haikou 571158, China
| | - Mingxue Zuo
- Beijing Key Laboratory of Gene Resource and Molecular Development, Laboratory of Neuroscience and Brain Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Xiaolong Fan
- Beijing Key Laboratory of Gene Resource and Molecular Development, Laboratory of Neuroscience and Brain Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Dapeng Li
- State Key Laboratory of Brain and Cognitive Sciences
| | - Yingyu Sun
- Beijing Key Laboratory of Gene Resource and Molecular Development, Laboratory of Neuroscience and Brain Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China
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Olivares-Hernández JD, García-García F, Camacho-Abrego I, Flores G, Juárez-Aguilar E. Intracerebroventricular administration of growth hormone induces morphological changes in pyramidal neurons of the hippocampus and prefrontal cortex in adult rats. Synapse 2018; 72:e22030. [DOI: 10.1002/syn.22030] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 01/30/2018] [Accepted: 01/30/2018] [Indexed: 01/14/2023]
Affiliation(s)
- Juan David Olivares-Hernández
- Department of Biomedicine; Health Sciences Institute, Universidad Veracruzana, Dr. Luis Castelazo-Ayala s/n, Industrial-Animas; Xalapa Veracruz 91190 México
- PhD Health Sciences Program. Health Sciences Institute; Universidad Veracruzana, Dr. Luis Castelazo-Ayala s/n, Industrial-Ánimas; Xalapa Veracruz 91190 México
| | - Fabio García-García
- Department of Biomedicine; Health Sciences Institute, Universidad Veracruzana, Dr. Luis Castelazo-Ayala s/n, Industrial-Animas; Xalapa Veracruz 91190 México
| | - Israel Camacho-Abrego
- Laboratory of Neuropsychiatry; Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla, 14 Sur 6301, CU San Manuel; Puebla Puebla 72570 México
| | - Gonzalo Flores
- Laboratory of Neuropsychiatry; Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla, 14 Sur 6301, CU San Manuel; Puebla Puebla 72570 México
| | - Enrique Juárez-Aguilar
- Department of Biomedicine; Health Sciences Institute, Universidad Veracruzana, Dr. Luis Castelazo-Ayala s/n, Industrial-Animas; Xalapa Veracruz 91190 México
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36
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Vázquez-Hernández N, González-Tapia DC, Martínez-Torres NI, González-Tapia D, González-Burgos I. Different patterns of motor activity induce differential plastic changes in pyramidal neurons in the motor cortex of rats: A Golgi study. Neurosci Lett 2017; 657:27-31. [DOI: 10.1016/j.neulet.2017.07.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 07/11/2017] [Accepted: 07/24/2017] [Indexed: 11/15/2022]
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Disruption of M1 Activity during Performance Plateau Impairs Consolidation of Motor Memories. J Neurosci 2017; 37:9197-9206. [PMID: 28821677 DOI: 10.1523/jneurosci.3916-16.2017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 07/27/2017] [Accepted: 08/10/2017] [Indexed: 11/21/2022] Open
Abstract
Upon exposure to a new sensorimotor relationship, motor behaviors iteratively change early in adaptation but eventually stabilize as adaptation proceeds. Behavioral work suggests that motor memory consolidation is initiated upon the attainment of asymptotic levels of performance. Separate lines of evidence point to a critical role of the primary motor cortex (M1) in consolidation. However, a causal relationship between M1 activity during asymptote and consolidation has yet to be demonstrated. The present study investigated this issue in male and female participants using single-pulse transcranial magnetic stimulation (TMS) to interfere with postmovement activity in M1 in two behavioral phases of a ramp-and-hold visuomotor adaptation paradigm. TMS was either provided after each trial of the ramp phase of adaptation when a gradual increase in the visuomotor rotation caused movements to be changing, or after each trial of the hold phase of adaptation when the rotation was held constant and movements tended to stabilize. Consolidation was assessed by measuring performance on the same task 24 h later. Results revealed that TMS did not influence adaptation to the new visuomotor relationship in either condition. Critically, however, TMS disruption of M1 activity selectively impaired consolidation of motor memories when it was provided during the hold phase of adaptation. This effect did not take place when TMS was delivered over adjacent dorsal premotor cortex or when motor behaviors in late adaptation were prevented from plateauing. Together, these data suggest that the impaired consolidation stemmed from interference with mechanisms of repetition-dependent plasticity in M1.SIGNIFICANCE STATEMENT The present work demonstrates that TMS disruption of M1 activity impairs the consolidation of motor memories selectively when performance reaches asymptotic levels during sensorimotor adaptation. These findings provide evidence for a causal contribution of M1 to motor memory formation when movements tend to repeat, likely through mechanisms of repetition-dependent plasticity.
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38
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Wu Q, Sun M, Bernard LP, Zhang H. Postsynaptic density 95 (PSD-95) serine 561 phosphorylation regulates a conformational switch and bidirectional dendritic spine structural plasticity. J Biol Chem 2017; 292:16150-16160. [PMID: 28790172 DOI: 10.1074/jbc.m117.782490] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 07/28/2017] [Indexed: 01/12/2023] Open
Abstract
Postsynaptic density 95 (PSD-95) is a major synaptic scaffolding protein that plays a key role in bidirectional synaptic plasticity, which is a process important for learning and memory. It is known that PSD-95 shows increased dynamics upon induction of plasticity. However, the underlying structural and functional changes in PSD-95 that mediate its role in plasticity remain unclear. Here we show that phosphorylation of PSD-95 at Ser-561 in its guanylate kinase (GK) domain, which is mediated by the partitioning-defective 1 (Par1) kinases, regulates a conformational switch and is important for bidirectional plasticity. Using a fluorescence resonance energy transfer (FRET) biosensor, we show that a phosphomimetic mutation of Ser-561 promotes an intramolecular interaction between GK and the nearby Src homology 3 (SH3) domain, leading to a closed conformation, whereas a non-phosphorylatable S561A mutation or inhibition of Par1 kinase activity decreases SH3-GK interaction, causing PSD-95 to adopt an open conformation. In addition, S561A mutation facilitates the interaction between PSD-95 and its binding partners. Fluorescence recovery after photobleaching imaging reveals that the S561A mutant shows increased stability, whereas the phosphomimetic S561D mutation increases PSD-95 dynamics at the synapse. Moreover, molecular replacement of endogenous PSD-95 with the S561A mutant blocks dendritic spine structural plasticity during chemical long-term potentiation and long-term depression. Endogenous Ser-561 phosphorylation is induced by synaptic NMDA receptor activation, and the SH3-GK domains exhibit a Ser-561 phosphorylation-dependent switch to a closed conformation during synaptic plasticity. Our results provide novel mechanistic insight into the regulation of PSD-95 in dendritic spine structural plasticity through phosphorylation-mediated regulation of protein dynamics and conformation.
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Affiliation(s)
- Qian Wu
- From the Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - Miao Sun
- From the Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - Laura P Bernard
- From the Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - Huaye Zhang
- From the Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
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39
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Hu F, Li T, Gong H, Chen Z, Jin Y, Xu G, Wang M. Bisphenol A Impairs Synaptic Plasticity by Both Pre- and Postsynaptic Mechanisms. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2017; 4:1600493. [PMID: 28852612 PMCID: PMC5566242 DOI: 10.1002/advs.201600493] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 02/10/2017] [Indexed: 05/30/2023]
Abstract
Bisphenol A (BPA), an environmental xenoestrogen, has been reported to induce learning and memory impairments in rodent animals. However, effects of BPA exposure on synaptic plasticity and the underlying physiological mechanisms remain elusive. Our behavioral and electrophysiological analyses show that BPA obviously perturbs hippocampal spatial memory of juvenile Sprague-Dawley rats after four weeks exposure, with significantly impaired long-term potentiation (LTP) in the hippocampus. These effects involve decreased spine density of pyramidal neurons, especially the apical dendritic spine. Further presynaptic findings show an overt inhibition of pulse-paired facilitation during electrophysiological recording, which suggest the decrease of presynaptic transmitter release and is consistent with reduced production of presynaptic glutamate after BPA exposure. Meanwhile, LTP-related glutamate receptors, NMDA receptor 2A (NR2A) and AMPA receptor 1 (GluR1), are significantly downregulated in BPA-exposed rats. Excitatory postsynaptic currents (EPSCs) results also show that EPSCNMDA, but not EPSCAMPA, is declined by 40% compared to the baseline in BPA-perfused brain slices. Taken together, these findings reveal that juvenile BPA exposure has negative effects on synaptic plasticity, which result from decreases in dendritic spine density and excitatory synaptic transmission. Importantly, this study also provides new insights into the dynamics of BPA-induced memory deterioration during the whole life of rats.
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Affiliation(s)
- Fan Hu
- School of Food Science and EngineeringHefei University of TechnologyHefeiAnhui230009P. R. China
| | - Tingting Li
- School of Food Science and EngineeringHefei University of TechnologyHefeiAnhui230009P. R. China
| | - Huarui Gong
- CAS Key Laboratory of Brain Function and DiseasesSchool of Life SciencesUniversity of Science and Technology of ChinaHefeiAnhui230027P. R. China
| | - Zhi Chen
- School of Food Science and EngineeringHefei University of TechnologyHefeiAnhui230009P. R. China
| | - Yan Jin
- CAS Key Laboratory of Brain Function and DiseasesSchool of Life SciencesUniversity of Science and Technology of ChinaHefeiAnhui230027P. R. China
| | - Guangwei Xu
- CAS Key Laboratory of Brain Function and DiseasesSchool of Life SciencesUniversity of Science and Technology of ChinaHefeiAnhui230027P. R. China
| | - Ming Wang
- CAS Key Laboratory of Brain Function and DiseasesSchool of Life SciencesUniversity of Science and Technology of ChinaHefeiAnhui230027P. R. China
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40
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Forsyth JK, Lewis DA. Mapping the Consequences of Impaired Synaptic Plasticity in Schizophrenia through Development: An Integrative Model for Diverse Clinical Features. Trends Cogn Sci 2017; 21:760-778. [PMID: 28754595 DOI: 10.1016/j.tics.2017.06.006] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 05/13/2017] [Accepted: 06/09/2017] [Indexed: 01/19/2023]
Abstract
Schizophrenia is associated with alterations in sensory, motor, and cognitive functions that emerge before psychosis onset; identifying pathogenic processes that can account for this multi-faceted phenotype remains a challenge. Accumulating evidence suggests that synaptic plasticity is impaired in schizophrenia. Given the role of synaptic plasticity in learning, memory, and neural circuit maturation, impaired plasticity may underlie many features of the schizophrenia syndrome. Here, we summarize the neurobiology of synaptic plasticity, review evidence that plasticity is impaired in schizophrenia, and explore a framework in which impaired synaptic plasticity interacts with brain maturation to yield the emergence of sensory, motor, cognitive, and psychotic features at different times during development in schizophrenia. Key gaps in the literature and future directions for testing this framework are discussed.
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Affiliation(s)
- Jennifer K Forsyth
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA, USA.
| | - David A Lewis
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
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41
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Xu T, Wang S, Lalchandani RR, Ding JB. Motor learning in animal models of Parkinson's disease: Aberrant synaptic plasticity in the motor cortex. Mov Disord 2017; 32:487-497. [PMID: 28343366 PMCID: PMC5483329 DOI: 10.1002/mds.26938] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 12/28/2016] [Accepted: 01/02/2017] [Indexed: 12/12/2022] Open
Abstract
In Parkinson's disease (PD), dopamine depletion causes major changes in the brain, resulting in the typical cardinal motor features of the disease. PD neuropathology has been restricted to postmortem examinations, which are limited to only a single time of PD progression. Models of PD in which dopamine tone in the brain is chemically or physically disrupted are valuable tools in understanding the mechanisms of the disease. The basal ganglia have been well studied in the context of PD, and circuit changes in response to dopamine loss have been linked to the motor dysfunctions in PD. However, the etiology of the cognitive dysfunctions that are comorbid in PD patients has remained unclear until now. In this article, we review recent studies exploring how dopamine depletion affects the motor cortex at the synaptic level. In particular, we highlight our recent findings on abnormal spine dynamics in the motor cortex of PD mouse models through in vivo time-lapse imaging and motor skill behavior assays. In combination with previous studies, a role of the motor cortex in skill learning and the impairment of this ability with the loss of dopamine are becoming more apparent. Taken together, we conclude with a discussion on the potential role for the motor cortex in PD, with the possibility of targeting the motor cortex for future PD therapeutics. © 2017 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Tonghui Xu
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics–Huazhong University of Science and Technology, Wuhan, China
- Ministry of Education (MoE) Key Laboratory for Biomedical Photonics, Department of Biomedical Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Shaofang Wang
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics–Huazhong University of Science and Technology, Wuhan, China
- Ministry of Education (MoE) Key Laboratory for Biomedical Photonics, Department of Biomedical Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Rupa R. Lalchandani
- Department of Neurosurgery, Stanford University School of Medicine, Palo Alto, California, USA
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Palo Alto, California, USA
| | - Jun B Ding
- Department of Neurosurgery, Stanford University School of Medicine, Palo Alto, California, USA
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Palo Alto, California, USA
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42
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Cortical synaptic and dendritic spine abnormalities in a presymptomatic TDP-43 model of amyotrophic lateral sclerosis. Sci Rep 2016; 6:37968. [PMID: 27897242 PMCID: PMC5126629 DOI: 10.1038/srep37968] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 10/31/2016] [Indexed: 12/11/2022] Open
Abstract
Layer V pyramidal neurons (LVPNs) within the motor cortex integrate sensory cues and co-ordinate voluntary control of motor output. In amyotrophic lateral sclerosis (ALS) LVPNs and spinal motor neurons degenerate. The pathogenesis of neural degeneration is unknown in ALS; 10% of cases have a genetic cause, whereas 90% are sporadic, with most of the latter showing TDP-43 inclusions. Clinical and experimental evidence implicate excitotoxicity as a prime aetiological candidate. Using patch clamp and dye-filling techniques in brain slices, combined with high-resolution confocal microscopy, we report increased excitatory synaptic inputs and dendritic spine densities in early presymptomatic mice carrying a TDP-43Q331K mutation. These findings demonstrate substantive alterations in the motor cortex neural network, long before an overt degenerative phenotype has been reported. We conclude that increased excitatory neurotransmission is a common pathophysiology amongst differing genetic cases of ALS and may be of relevance to the 95% of sporadic ALS cases that exhibit TDP-43 inclusions.
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43
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Chen Y, Geng Y. Synapse engineering: A new level of brain modulation. Brain Res Bull 2016; 129:23-29. [PMID: 27721029 DOI: 10.1016/j.brainresbull.2016.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 10/04/2016] [Accepted: 10/05/2016] [Indexed: 01/09/2023]
Abstract
Brain modulation is a powerful approach to study brain function in vivo. Tremendous progress had been made by controlling brain activity with different brain modulation tools. Synapse is the more fundamental functional unit of brain. In theory, synapse engineering could modulate brain function more precisely. However this had not been possible until recently. Our review provides a brief introduction of various brain modulation methods, and elaborates on a recently developed synapse-engineering tool. This technique allows modulation of specific synapses in vivo for the first time and has been used to clarify the causal role of synaptic plasticity in learning and memory. We also discuss its potentials for further development.
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Affiliation(s)
- Yelin Chen
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 26 Qiueyue Road, B6, Pudongxinqu, Shanghai 201203, China.
| | - Yang Geng
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 26 Qiueyue Road, B6, Pudongxinqu, Shanghai 201203, China
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44
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Knoblauch A, Sommer FT. Structural Plasticity, Effectual Connectivity, and Memory in Cortex. Front Neuroanat 2016; 10:63. [PMID: 27378861 PMCID: PMC4909771 DOI: 10.3389/fnana.2016.00063] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 05/26/2016] [Indexed: 11/13/2022] Open
Abstract
Learning and memory is commonly attributed to the modification of synaptic strengths in neuronal networks. More recent experiments have also revealed a major role of structural plasticity including elimination and regeneration of synapses, growth and retraction of dendritic spines, and remodeling of axons and dendrites. Here we work out the idea that one likely function of structural plasticity is to increase "effectual connectivity" in order to improve the capacity of sparsely connected networks to store Hebbian cell assemblies that are supposed to represent memories. For this we define effectual connectivity as the fraction of synaptically linked neuron pairs within a cell assembly representing a memory. We show by theory and numerical simulation the close links between effectual connectivity and both information storage capacity of neural networks and effective connectivity as commonly employed in functional brain imaging and connectome analysis. Then, by applying our model to a recently proposed memory model, we can give improved estimates on the number of cell assemblies that can be stored in a cortical macrocolumn assuming realistic connectivity. Finally, we derive a simplified model of structural plasticity to enable large scale simulation of memory phenomena, and apply our model to link ongoing adult structural plasticity to recent behavioral data on the spacing effect of learning.
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Affiliation(s)
- Andreas Knoblauch
- Informatics Faculty, Albstadt-Sigmaringen University Albstadt, Germany
| | - Friedrich T Sommer
- Redwood Center for Theoretical Neuroscience, University of California at Berkeley Berkeley, CA, USA
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45
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Kida H, Tsuda Y, Ito N, Yamamoto Y, Owada Y, Kamiya Y, Mitsushima D. Motor Training Promotes Both Synaptic and Intrinsic Plasticity of Layer II/III Pyramidal Neurons in the Primary Motor Cortex. Cereb Cortex 2016; 26:3494-507. [PMID: 27193420 PMCID: PMC4961021 DOI: 10.1093/cercor/bhw134] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Motor skill training induces structural plasticity at dendritic spines in the primary motor cortex (M1). To further analyze both synaptic and intrinsic plasticity in the layer II/III area of M1, we subjected rats to a rotor rod test and then prepared acute brain slices. Motor skill consistently improved within 2 days of training. Voltage clamp analysis showed significantly higher α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid/N-methyl-d-aspartate (AMPA/NMDA) ratios and miniature EPSC amplitudes in 1-day trained rats compared with untrained rats, suggesting increased postsynaptic AMPA receptors in the early phase of motor learning. Compared with untrained controls, 2-days trained rats showed significantly higher miniature EPSC amplitude and frequency. Paired-pulse analysis further demonstrated lower rates in 2-days trained rats, suggesting increased presynaptic glutamate release during the late phase of learning. One-day trained rats showed decreased miniature IPSC frequency and increased paired-pulse analysis of evoked IPSC, suggesting a transient decrease in presynaptic γ-aminobutyric acid (GABA) release. Moreover, current clamp analysis revealed lower resting membrane potential, higher spike threshold, and deeper afterhyperpolarization in 1-day trained rats—while 2-days trained rats showed higher membrane potential, suggesting dynamic changes in intrinsic properties. Our present results indicate dynamic changes in glutamatergic, GABAergic, and intrinsic plasticity in M1 layer II/III neurons after the motor training.
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Affiliation(s)
| | | | | | - Yui Yamamoto
- Department of Organ Anatomy, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube, Yamaguchi 755-8505, Japan
| | - Yuji Owada
- Department of Organ Anatomy, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube, Yamaguchi 755-8505, Japan
| | - Yoshinori Kamiya
- Uonuma Institute of Community Medicine, Niigata University Medical and Dental Hospital, 4132 Urasa, Minami-uonuma, Niigata 949-7302, Japan
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46
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Paggiaro A, Birbaumer N, Cavinato M, Turco C, Formaggio E, Del Felice A, Masiero S, Piccione F. Magnetoencephalography in Stroke Recovery and Rehabilitation. Front Neurol 2016; 7:35. [PMID: 27065338 PMCID: PMC4815903 DOI: 10.3389/fneur.2016.00035] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 03/04/2016] [Indexed: 01/01/2023] Open
Abstract
Magnetoencephalography (MEG) is a non-invasive neurophysiological technique used to study the cerebral cortex. Currently, MEG is mainly used clinically to localize epileptic foci and eloquent brain areas in order to avoid damage during neurosurgery. MEG might, however, also be of help in monitoring stroke recovery and rehabilitation. This review focuses on experimental use of MEG in neurorehabilitation. MEG has been employed to detect early modifications in neuroplasticity and connectivity, but there is insufficient evidence as to whether these methods are sensitive enough to be used as a clinical diagnostic test. MEG has also been exploited to derive the relationship between brain activity and movement kinematics for a motor-based brain–computer interface. In the current body of experimental research, MEG appears to be a powerful tool in neurorehabilitation, but it is necessary to produce new data to confirm its clinical utility.
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Affiliation(s)
- Andrea Paggiaro
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation , Venice , Italy
| | - Niels Birbaumer
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation, Venice, Italy; Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Marianna Cavinato
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation , Venice , Italy
| | - Cristina Turco
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation , Venice , Italy
| | - Emanuela Formaggio
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation , Venice , Italy
| | - Alessandra Del Felice
- Section of Rehabilitation, Department of Neuroscience, University of Padova , Padova , Italy
| | - Stefano Masiero
- Section of Rehabilitation, Department of Neuroscience, University of Padova , Padova , Italy
| | - Francesco Piccione
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation , Venice , Italy
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47
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Hu F, Ge MM, Chen WH. Effects of lead exposure on dendrite and spine development in hippocampal dentate gyrus areas of rats. Synapse 2016; 70:87-97. [DOI: 10.1002/syn.21873] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 10/27/2015] [Accepted: 11/02/2015] [Indexed: 11/07/2022]
Affiliation(s)
- Fan Hu
- School of Biotechnology and Food Engineering; Hefei University of Technology; Hefei Anhui 230009 People's Republic of China
| | - Meng-Meng Ge
- School of Biotechnology and Food Engineering; Hefei University of Technology; Hefei Anhui 230009 People's Republic of China
| | - Wei-Heng Chen
- School of Life Sciences; University of Science and Technology of China; Hefei Anhui 230027 People's Republic of China
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48
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Garcia-Munoz M, Arbuthnott GW. Basal ganglia-thalamus and the "crowning enigma". Front Neural Circuits 2015; 9:71. [PMID: 26582979 PMCID: PMC4631818 DOI: 10.3389/fncir.2015.00071] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 10/22/2015] [Indexed: 11/13/2022] Open
Abstract
When Hubel (1982) referred to layer 1 of primary visual cortex as "… a 'crowning mystery' to keep area-17 physiologists busy for years to come …" he could have been talking about any cortical area. In the 80's and 90's there were no methods to examine this neuropile on the surface of the cortex: a tangled web of axons and dendrites from a variety of different places with unknown specificities and doubtful connections to the cortical output neurons some hundreds of microns below. Recently, three changes have made the crowning enigma less of an impossible mission: the clear presence of neurons in layer 1 (L1), the active conduction of voltage along apical dendrites and optogenetic methods that might allow us to look at one source of input at a time. For all of those reasons alone, it seems it is time to take seriously the function of L1. The functional properties of this layer will need to wait for more experiments but already L1 cells are GAD67 positive, i.e., inhibitory! They could reverse the sign of the thalamic glutamate (GLU) input for the entire cortex. It is at least possible that in the near future normal activity of individual sources of L1 could be detected using genetic tools. We are at the outset of important times in the exploration of thalamic functions and perhaps the solution to the crowning enigma is within sight. Our review looks forward to that solution from the solid basis of the anatomy of the basal ganglia output to motor thalamus. We will focus on L1, its afferents, intrinsic neurons and its influence on responses of pyramidal neurons in layers 2/3 and 5. Since L1 is present in the whole cortex we will provide a general overview considering evidence mainly from the somatosensory (S1) cortex before focusing on motor cortex.
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Affiliation(s)
| | - Gordon W Arbuthnott
- Okinawa Institute of Science and Technology Graduate University Okinawa, Japan
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49
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Huang YB, Hu CR, Zhang L, Yin W, Hu B. In Vivo Study of Dynamics and Stability of Dendritic Spines on Olfactory Bulb Interneurons in Xenopus laevis Tadpoles. PLoS One 2015; 10:e0140752. [PMID: 26485435 PMCID: PMC4617280 DOI: 10.1371/journal.pone.0140752] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Accepted: 09/30/2015] [Indexed: 01/27/2023] Open
Abstract
Dendritic spines undergo continuous remodeling during development of the nervous system. Their stability is essential for maintaining a functional neuronal circuit. Spine dynamics and stability of cortical excitatory pyramidal neurons have been explored extensively in mammalian animal models. However, little is known about spiny interneurons in non-mammalian vertebrate models. In the present study, neuronal morphology was visualized by single-cell electroporation. Spiny neurons were surveyed in the Xenopus tadpole brain and observed to be widely distributed in the olfactory bulb and telencephalon. DsRed- or PSD95-GFP-expressing spiny interneurons in the olfactory bulb were selected for in vivo time-lapse imaging. Dendritic protrusions were classified as filopodia, thin, stubby, or mushroom spines based on morphology. Dendritic spines on the interneurons were highly dynamic, especially the filopodia and thin spines. The stubby and mushroom spines were relatively more stable, although their stability significantly decreased with longer observation intervals. The 4 spine types exhibited diverse preferences during morphological transitions from one spine type to others. Sensory deprivation induced by severing the olfactory nerve to block the input of mitral/tufted cells had no significant effects on interneuron spine stability. Hence, a new model was established in Xenopus laevis tadpoles to explore dendritic spine dynamics in vivo.
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Affiliation(s)
- Yu-Bin Huang
- Chinese Academy of Sciences Key Laboratory of Brain Function and Disease, and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province, P. R. China
| | - Chun-Rui Hu
- Chinese Academy of Sciences Key Laboratory of Brain Function and Disease, and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province, P. R. China
| | - Li Zhang
- Chinese Academy of Sciences Key Laboratory of Brain Function and Disease, and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province, P. R. China
| | - Wu Yin
- Chinese Academy of Sciences Key Laboratory of Brain Function and Disease, and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province, P. R. China
| | - Bing Hu
- Chinese Academy of Sciences Key Laboratory of Brain Function and Disease, and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province, P. R. China
- * E-mail:
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Gabor C, Lymer J, Phan A, Choleris E. Rapid effects of the G-protein coupled oestrogen receptor (GPER) on learning and dorsal hippocampus dendritic spines in female mice. Physiol Behav 2015; 149:53-60. [DOI: 10.1016/j.physbeh.2015.05.017] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 05/13/2015] [Accepted: 05/19/2015] [Indexed: 12/24/2022]
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