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Kim T, Park H, Tanaka-Yamamoto K, Yamamoto Y. Developmental timing-dependent organization of synaptic connections between mossy fibers and granule cells in the cerebellum. Commun Biol 2023; 6:446. [PMID: 37095324 PMCID: PMC10125988 DOI: 10.1038/s42003-023-04825-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 04/07/2023] [Indexed: 04/26/2023] Open
Abstract
The long-standing hypothesis that synapses between mossy fibers (MFs) and cerebellar granule cells (GCs) are organized according to the origins of MFs and locations of GC axons, parallel fibers (PFs), is supported by recent findings. However, the mechanisms of such organized synaptic connections remain unknown. Here, using our technique that enabled PF location-dependent labeling of GCs in mice, we confirmed that synaptic connections of GCs with specific MFs originating from the pontine nucleus (PN-MFs) and dorsal column nuclei (DCoN-MFs) were gently but differentially organized according to their PF locations. We then found that overall MF-GC synaptic connectivity was biased in a way that dendrites of GCs having nearby PFs tended to connect with the same MF terminals, implying that the MF origin- and PF location-dependent organization is associated with the overall biased MF-GC synaptic connectivity. Furthermore, the development of PN-MFs preceded that of DCoN-MFs, which matches the developmental sequence of GCs that preferentially connect with each type of these MFs. Thus, our results revealed that overall MF-GC synaptic connectivity is biased in terms of PF locations, and suggested that such connectivity is likely the result of synaptic formation between developmental timing-matched partners.
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Affiliation(s)
- Taegon Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Heeyoun Park
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Keiko Tanaka-Yamamoto
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.
| | - Yukio Yamamoto
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.
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Kourosh-Arami M, Hosseini N, Mohsenzadegan M, Komaki A, Joghataei MT. Neurophysiologic implications of neuronal nitric oxide synthase. Rev Neurosci 2021; 31:617-636. [PMID: 32739909 DOI: 10.1515/revneuro-2019-0111] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 03/21/2020] [Indexed: 12/12/2022]
Abstract
The molecular and chemical properties of neuronal nitric oxide synthase (nNOS) have made it a key mediator in many physiological functions and signaling transduction. The NOS monomer is inactive, but the dimer form is active. There are three forms of NOS, which are neuronal (nNOS), inducible (iNOS), and endothelial (eNOS) nitric oxide synthase. nNOS regulates nitric oxide (NO) synthesis which is the mechanism used mostly by neurons to produce NO. nNOS expression and activation is regulated by some important signaling proteins, such as cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB), calmodulin (CaM), heat shock protein 90 (HSP90)/HSP70. nNOS-derived NO has been implicated in modulating many physiological functions, such as synaptic plasticity, learning, memory, neurogenesis, etc. In this review, we have summarized recent studies that have characterized structural features, subcellular localization, and factors that regulate nNOS function. Finally, we have discussed the role of nNOS in the developing brain under a wide range of physiological conditions, especially long-term potentiation and depression.
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Affiliation(s)
- Masoumeh Kourosh-Arami
- Department of Neuroscience, School of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Nasrin Hosseini
- Neuroscience Research Center, Iran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Monireh Mohsenzadegan
- Department of Laboratory Sciences, Allied Medical College, Iran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Alireza Komaki
- Department of Physiology, Medical College, Hamedan University of Medical Sciences, Hamedan, Islamic Republic of Iran
| | - Mohammad Taghi Joghataei
- Department of Neuroscience, School of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Islamic Republic of Iran
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de Souza RF, Augusto RL, de Moraes SRA, de Souza FB, Gonçalves LVDP, Pereira DD, Moreno GMM, de Souza FMA, Andrade-da-Costa BLDS. Ultra-Endurance Associated With Moderate Exercise in Rats Induces Cerebellar Oxidative Stress and Impairs Reactive GFAP Isoform Profile. Front Mol Neurosci 2020; 13:157. [PMID: 32982688 PMCID: PMC7492828 DOI: 10.3389/fnmol.2020.00157] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 07/29/2020] [Indexed: 12/11/2022] Open
Abstract
Ultra-endurance (UE) race has been associated with brain metabolic changes, but it is still unknown which regions are vulnerable. This study investigated whether high-volume training in rodents, even under moderate intensity, can induce cerebellar oxidative and inflammatory status. Forty-five adult rats were divided into six groups according to a training period, followed or not by an exhaustion test (ET) that simulated UE: control (C), control + ET (C-ET), moderate-volume (MV) training and MV-ET, high-volume training (HV) and HV-ET. The training period was 30 (MV) and 90 (HV) min/day, 5 times/week for 3 months as a continuous running on a treadmill at a maximum velocity of 12 m/min. After 24 h, the ET was performed at 50% maximum velocities up to the animals refused to run, and then serum lactate levels were evaluated. Serum and cerebellar homogenates were obtained 24 h after ET. Serum creatine kinase (CK), lactate dehydrogenase (LDH), and corticosterone levels were assessed. Lipid peroxidation (LP), nitric oxide (NO), Interleukin 1β (IL-1β), and GFAP proteins, reduced and oxidized glutathione (GSH and GSSG) levels, superoxide dismutase (SOD) and catalase (CAT) activities were quantified in the cerebellum. Serum lactate concentrations were lower in MV-ET (∼20%) and HV-ET (∼40%) compared to the C-ET group. CK and corticosterone levels were increased more than ∼ twofold by HV training compared to control. ET increased CK levels in MV-ET vs. MV group (P = 0.026). HV induced higher LP levels (∼40%), but an additive effect of ET was only seen in the MV-ET group (P = 0.02). SOD activity was higher in all trained groups vs. C and C-ET (P < 0.05). CAT activity, however, was intensified only in the MV group (P < 0.02). The 50 kDa GFAP levels were enhanced in C-ET and MV-ET vs. respective controls, while 42 kDa (∼40%) and 39 kDa (∼26%) isoform levels were reduced. In the HV-ET group, the 50 KDa isoform amount was reduced ∼40-60% compared to the other groups and the 39 KDa isoform, increased sevenfold. LDH levels, GSH/GSSG ratio, and NO production were not modified. ET elevated IL-1β levels in the CT and MV groups. Data shows that cerebellar resilience to oxidative damage may be maintained under moderate-volume training, but it is reduced by UE running. High-volume training per se provoked systemic metabolic changes, cerebellar lipid peroxidation, and unbalanced enzymatic antioxidant resource. UE after high-volume training modified the GFAP isoform profile suggesting impaired astrocyte reactivity in the cerebellum.
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Affiliation(s)
- Raphael Fabricio de Souza
- Laboratory of Neurophysiology, Department of Physiology and Pharmacology, Center of Biosciences, Federal University of Pernambuco, Recife, Brazil
- Postgraduate Program in Neuropsychiatry and Behavioral Sciences, Federal University of Pernambuco, Recife, Brazil
- Department of Physical Education, Federal University of Sergipe, São Cristovão, Brazil
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports – GEPEPS, Federal University of Sergipe, São Cristovão, Brazil
| | - Ricielle Lopes Augusto
- Laboratory of Neurophysiology, Department of Physiology and Pharmacology, Center of Biosciences, Federal University of Pernambuco, Recife, Brazil
| | - Silvia Regina Arruda de Moraes
- Laboratory of Neuromuscular Plasticity, Department of Anatomy, Center of Biosciences, Federal University of Pernambuco, Recife, Brazil
| | - Fabio Borges de Souza
- Laboratory of Neurophysiology, Department of Physiology and Pharmacology, Center of Biosciences, Federal University of Pernambuco, Recife, Brazil
| | - Lílian Vanessa da Penha Gonçalves
- Laboratory of Neurophysiology, Department of Physiology and Pharmacology, Center of Biosciences, Federal University of Pernambuco, Recife, Brazil
| | - Danielle Dutra Pereira
- Laboratory of Neurophysiology, Department of Physiology and Pharmacology, Center of Biosciences, Federal University of Pernambuco, Recife, Brazil
| | - Gisele Machado Magalhães Moreno
- Laboratory of Neurophysiology, Department of Physiology and Pharmacology, Center of Biosciences, Federal University of Pernambuco, Recife, Brazil
| | - Fernanda Maria Araujo de Souza
- Laboratory of Neuropharmacology and Integrative Physiology, Center of Biosciences, Federal University of Alagoas, Maceió, Brazil
| | - Belmira Lara da Silveira Andrade-da-Costa
- Laboratory of Neurophysiology, Department of Physiology and Pharmacology, Center of Biosciences, Federal University of Pernambuco, Recife, Brazil
- Postgraduate Program in Neuropsychiatry and Behavioral Sciences, Federal University of Pernambuco, Recife, Brazil
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Canepari M. Is Purkinje Neuron Hyperpolarisation Important for Cerebellar Synaptic Plasticity? A Retrospective and Prospective Analysis. THE CEREBELLUM 2020; 19:869-878. [PMID: 32654026 DOI: 10.1007/s12311-020-01164-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Two recent studies have demonstrated that the dendritic Ca2+ signal associated with a climbing fibre (CF) input to the cerebellar Purkinje neuron (PN) depends on the membrane potential (Vm). Specifically, when the cell is hyperpolarised, this signal is mediated by T-type voltage-gated Ca2+ channels; in contrast, when the cell is firing, the CF-PN signal is mediated by P/Q-type voltage-gated Ca2+ channels. When the CF input is paired with parallel fibre (PF) activity, the signal is locally amplified at the sites of PF-activated synapses according to the Vm at the time of the CF input, suggesting that the standing Vm is a critical parameter for the induction of PF synaptic plasticity. In this review, I analyse how the Vm can potentially play a role in cerebellar learning focussing, in particular, on the hyperpolarised state that appears to occur episodically, since PNs are mostly firing under physiological conditions. By revisiting the recent literature reporting in vivo recordings and synaptic plasticity studies, I speculate on how a putative role of the PN Vm can provide an interpretation for the results of these studies.
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Affiliation(s)
- Marco Canepari
- University of Grenoble Alpes, CNRS, LIPhy, F-38000, Grenoble, France. .,Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France. .,Institut National de la Santé et Recherche Médicale, Paris, France.
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Kawato M, Ohmae S, Hoang H, Sanger T. 50 Years Since the Marr, Ito, and Albus Models of the Cerebellum. Neuroscience 2020; 462:151-174. [PMID: 32599123 DOI: 10.1016/j.neuroscience.2020.06.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/10/2020] [Accepted: 06/15/2020] [Indexed: 12/18/2022]
Abstract
Fifty years have passed since David Marr, Masao Ito, and James Albus proposed seminal models of cerebellar functions. These models share the essential concept that parallel-fiber-Purkinje-cell synapses undergo plastic changes, guided by climbing-fiber activities during sensorimotor learning. However, they differ in several important respects, including holistic versus complementary roles of the cerebellum, pattern recognition versus control as computational objectives, potentiation versus depression of synaptic plasticity, teaching signals versus error signals transmitted by climbing-fibers, sparse expansion coding by granule cells, and cerebellar internal models. In this review, we evaluate different features of the three models based on recent computational and experimental studies. While acknowledging that the three models have greatly advanced our understanding of cerebellar control mechanisms in eye movements and classical conditioning, we propose a new direction for computational frameworks of the cerebellum, that is, hierarchical reinforcement learning with multiple internal models.
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Affiliation(s)
- Mitsuo Kawato
- Brain Information Communication Research Group, Advanced Telecommunications Research Institutes International (ATR), Hikaridai 2-2-2, "Keihanna Science City", Kyoto 619-0288, Japan; Center for Advanced Intelligence Project (AIP), RIKEN, Nihonbashi Mitsui Building, 1-4-1 Nihonbashi, Chuo-ku, Tokyo 103-0027, Japan.
| | - Shogo Ohmae
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
| | - Huu Hoang
- Brain Information Communication Research Group, Advanced Telecommunications Research Institutes International (ATR), Hikaridai 2-2-2, "Keihanna Science City", Kyoto 619-0288, Japan
| | - Terry Sanger
- Department of Electrical Engineering, University of California, Irvine, 4207 Engineering Hall, Irvine CA 92697-2625, USA; Children's Hospital of Orange County, 1201 W La Veta Ave, Orange, CA 92868, USA.
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6
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Moreno-Rius J. Opioid addiction and the cerebellum. Neurosci Biobehav Rev 2019; 107:238-251. [DOI: 10.1016/j.neubiorev.2019.09.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 09/06/2019] [Accepted: 09/10/2019] [Indexed: 01/10/2023]
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Safaryan K, Maex R, Davey N, Adams R, Steuber V. Nonspecific synaptic plasticity improves the recognition of sparse patterns degraded by local noise. Sci Rep 2017; 7:46550. [PMID: 28425471 PMCID: PMC5397845 DOI: 10.1038/srep46550] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 03/22/2017] [Indexed: 01/22/2023] Open
Abstract
Many forms of synaptic plasticity require the local production of volatile or rapidly diffusing substances such as nitric oxide. The nonspecific plasticity these neuromodulators may induce at neighboring non-active synapses is thought to be detrimental for the specificity of memory storage. We show here that memory retrieval may benefit from this non-specific plasticity when the applied sparse binary input patterns are degraded by local noise. Simulations of a biophysically realistic model of a cerebellar Purkinje cell in a pattern recognition task show that, in the absence of noise, leakage of plasticity to adjacent synapses degrades the recognition of sparse static patterns. However, above a local noise level of 20%, the model with nonspecific plasticity outperforms the standard, specific model. The gain in performance is greatest when the spatial distribution of noise in the input matches the range of diffusion-induced plasticity. Hence non-specific plasticity may offer a benefit in noisy environments or when the pressure to generalize is strong.
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Affiliation(s)
- Karen Safaryan
- Centre for Computer Science and Informatics Research, University of Hertfordshire, College Lane, AL10 9AB Hatfield, United Kingdom.,Department of Physics and Astronomy, Knudsen Hall, University of California, Los Angeles CA, 90095-0001, USA
| | - Reinoud Maex
- Centre for Computer Science and Informatics Research, University of Hertfordshire, College Lane, AL10 9AB Hatfield, United Kingdom.,Department of Cognitive Sciences, Ecole Normale Supérieure, rue d'Ulm 25, 75005 Paris, France
| | - Neil Davey
- Centre for Computer Science and Informatics Research, University of Hertfordshire, College Lane, AL10 9AB Hatfield, United Kingdom
| | - Rod Adams
- Centre for Computer Science and Informatics Research, University of Hertfordshire, College Lane, AL10 9AB Hatfield, United Kingdom
| | - Volker Steuber
- Centre for Computer Science and Informatics Research, University of Hertfordshire, College Lane, AL10 9AB Hatfield, United Kingdom
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Age-dependent changes in the glutamate-nitric oxide pathway in the hippocampus of the triple transgenic model of Alzheimer's disease: implications for neurometabolic regulation. Neurobiol Aging 2016; 46:84-95. [PMID: 27460153 DOI: 10.1016/j.neurobiolaging.2016.06.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Revised: 06/16/2016] [Accepted: 06/21/2016] [Indexed: 12/26/2022]
Abstract
Age-dependent changes in nitric oxide ((•)NO) concentration dynamics may play a significant role in both decaying synaptic and metabolic functions in Alzheimer's disease (AD). This neuromodulator acts presynaptically to increase vesicle release and glutamatergic transmission and also regulates mitochondrial function. Under conditions of altered intracellular redox environment, (•)NO may react and produce reactive species such as peroxynitrite. Using the triple transgenic mouse model of AD (3xTgAD), we investigated age-dependent changes in the glutamate-(•)NO axis in the hippocampus. Direct measurement of (•)NO concentration dynamics revealed a significant increase in N-methyl-D-aspartate type receptor-evoked peak (•)NO in the 3xTgAD model at an early age. Aging produced a decrease in peak (•)NO accompanied by significant decrease in production and decay rates in the transgenic model. Evaluation of energy metabolism revealed age-dependent decrease in basal oxygen consumption rate, a general decrease in mitochondrial oxidative phosphorylation parameters, and loss in mitochondrial sparing capacity in both genotypes. Finally, we observed age-dependent increase in 3-nitrotyrosine residues in the hippocampus, consistent with a putative shift in (•)NO bioactivity toward oxidative chemistry associated with neurotoxicity.
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Bower JM. The 40-year history of modeling active dendrites in cerebellar Purkinje cells: emergence of the first single cell "community model". Front Comput Neurosci 2015; 9:129. [PMID: 26539104 PMCID: PMC4611061 DOI: 10.3389/fncom.2015.00129] [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: 11/14/2014] [Accepted: 10/02/2015] [Indexed: 11/13/2022] Open
Abstract
The subject of the effects of the active properties of the Purkinje cell dendrite on neuronal function has been an active subject of study for more than 40 years. Somewhat unusually, some of these investigations, from the outset have involved an interacting combination of experimental and model-based techniques. This article recounts that 40-year history, and the view of the functional significance of the active properties of the Purkinje cell dendrite that has emerged. It specifically considers the emergence from these efforts of what is arguably the first single cell "community" model in neuroscience. The article also considers the implications of the development of this model for future studies of the complex properties of neuronal dendrites.
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Brown SA, Loew LM. Integration of modeling with experimental and clinical findings synthesizes and refines the central role of inositol 1,4,5-trisphosphate receptor 1 in spinocerebellar ataxia. Front Neurosci 2015; 8:453. [PMID: 25653583 PMCID: PMC4300941 DOI: 10.3389/fnins.2014.00453] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 12/22/2014] [Indexed: 12/22/2022] Open
Abstract
A suite of models was developed to study the role of inositol 1,4,5-trisphosphate receptor 1 (IP3R1) in spinocerebellar ataxias (SCAs). Several SCAs are linked to reduced abundance of IP3R1 or to supranormal sensitivity of the receptor to activation by its ligand inositol 1,4,5-trisphosphate (IP3). Detailed multidimensional models have been created to simulate biochemical calcium signaling and membrane electrophysiology in cerebellar Purkinje neurons. In these models, IP3R1-mediated calcium release is allowed to interact with ion channel response on the cell membrane. Experimental findings in mice and clinical observations in humans provide data input for the models. The SCA modeling suite helps interpret experimental results and provides suggestions to guide experiments. The models predict IP3R1 supersensitivity in SCA1 and compensatory mechanisms in SCA1, SCA2, and SCA3. Simulations explain the impact of calcium buffer proteins. Results show that IP3R1-mediated calcium release activates voltage-gated calcium-activated potassium channels in the plasma membrane. The SCA modeling suite unifies observations from experiments in a number of SCAs. The cadre of simulations demonstrates the central role of IP3R1.
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Affiliation(s)
| | - Leslie M Loew
- Richard D. Berlin Center for Cell Analysis and Modeling, University of Connecticut Health Center Farmington, CT, USA
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Ledo A, Lourenço CF, Caetano M, Barbosa RM, Laranjinha J. Age-associated changes of nitric oxide concentration dynamics in the central nervous system of Fisher 344 rats. Cell Mol Neurobiol 2014; 35:33-44. [PMID: 25274046 DOI: 10.1007/s10571-014-0115-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 09/17/2014] [Indexed: 01/25/2023]
Abstract
The increase in life expectancy is accompanied by an increased risk of developing neurodegenerative disorders and age is the most relevant risk factor for the appearance of cognitive decline. While decreased neuronal count has been proposed to be a major contributing factor to the appearance of age-associated cognitive decline, it appears to be insufficient to fully account for the decay in mental function in aged individuals. Nitric oxide ((•)NO) is a ubiquitous signaling molecule in the mammalian central nervous system. Closely linked to the activation of glutamatergic transmission in several structures of the brain, neuron-derived (•)NO can act as a neuromodulator in synaptic plasticity but has also been linked to neuronal toxicity and degenerative processes. Many studies have proposed that changes in the glutamate-(•)NO signaling pathway may be implicated in age-dependent cognitive decline and that the exact effect of such changes may be region specific. Due to its peculiar physical-chemical properties, namely hydrophobicity, small size, and rapid diffusion properties, the rate and pattern of (•)NO concentration changes are critical determinants for the understanding of its bioactivity in the brain. Here we show a detailed study of how (•)NO concentration dynamics change in the different regions of the brain of Fisher 344 rats (F344) during aging. Using microelectrodes inserted into the living brain of anesthetized F344 rats, we show here that glutamate-induced (•)NO concentration dynamics decrease in the hippocampus, striatum, and cerebral cortex as animals age. performance in behavior testing of short-term and spatial memory, suggesting that the impairment in the glutamate:nNOS pathway represents a functional critical event in cognitive decline during aging.
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Affiliation(s)
- Ana Ledo
- Center for Neuroscience and Cell Biology, Coimbra, Portugal
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12
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Honda M, Urakubo H, Koumura T, Kuroda S. A common framework of signal processing in the induction of cerebellar LTD and cortical STDP. Neural Netw 2013; 43:114-24. [PMID: 23500505 DOI: 10.1016/j.neunet.2013.01.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 01/21/2013] [Accepted: 01/26/2013] [Indexed: 12/24/2022]
Abstract
Cerebellar long-term depression (LTD) and cortical spike-timing-dependent synaptic plasticity (STDP) are two well-known and well-characterized types of synaptic plasticity. Induction of both types of synaptic plasticity depends on the spike timing, pairing frequency, and pairing numbers of two different sources of spiking. This implies that the induction of synaptic plasticity may share common frameworks in terms of signal processing regardless of the different signaling pathways involved in the two types of synaptic plasticity. Here we propose that both types share common frameworks of signal processing for spike-timing, pairing-frequency, and pairing-numbers detection. We developed system models of both types of synaptic plasticity and analyzed signal processing in the induction of synaptic plasticity. We found that both systems have upstream subsystems for spike-timing detection and downstream subsystems for pairing-frequency and pairing-numbers detection. The upstream systems used multiplication of signals from the feedback filters and nonlinear functions for spike-timing detection. The downstream subsystems used temporal filters with longer time constants for pairing-frequency detection and nonlinear switch-like functions for pairing-numbers detection, indicating that the downstream subsystems serve as a leaky integrate-and-fire system. Thus, our findings suggest that a common conceptual framework for the induction of synaptic plasticity exists despite the differences in molecular species and pathways.
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Kawaguchi SY, Hirano T. Gating of long-term depression by Ca2+/calmodulin-dependent protein kinase II through enhanced cGMP signalling in cerebellar Purkinje cells. J Physiol 2013; 591:1707-30. [PMID: 23297306 DOI: 10.1113/jphysiol.2012.245787] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Long-term depression (LTD) at parallel fibre synapses on a cerebellar Purkinje cell has been regarded as a cellular basis for motor learning. Although Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) has been implicated in the LTD induction as an important Ca(2+)-sensing molecule, the underlying signalling mechanism remains unclear. Here, we attempted to explore the potential signalling pathway underlying the CaMKII involvement in LTD using a systems biology approach, combined with validation by electrophysiological and FRET imaging experiments on a rat cultured Purkinje cell. Model simulation predicted the following cascade as a candidate mechanism for the CaMKII contribution to LTD: CaMKII negatively regulates phosphodiesterase 1 (PDE1), subsequently facilitates the cGMP/protein kinase G (PKG) signalling pathway and down-regulates protein phosphatase 2A (PP-2A), thus supporting the LTD-inducing positive feedback loop consisting of mutual activation of protein kinase C (PKC) and mitogen-activated protein kinase (MAPK). This model suggestion was corroborated by whole-cell patch clamp recording experiments. In addition, FRET measurement of intracellular cGMP concentration revealed that CaMKII activation causes sustained increase of cGMP, supporting the signalling mechanism of LTD induction by CaMKII. Furthermore, we found that activation of the cGMP/PKG pathway by nitric oxide (NO) can support LTD induction without activation of CaMKII. Thus, this study clarified interaction between NO and Ca(2+)/CaMKII, two important factors required for LTD.
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Affiliation(s)
- Shin-ya Kawaguchi
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
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14
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Abstract
Cerebellar long-term depression (LTD) is a form of long-term synaptic plasticity that is triggered by calcium(Ca2+) signals in the postsynaptic Purkinje cell. This Ca2+comes both from IP3-mediated release from intracellular Ca2+ stores, as well as from Ca2+ influx through voltage-gated Ca2+ channels. The Ca2+ signal that triggers LTD occurs locally within dendritic spines and is due to supralinear summation of signals coming from these two Ca2+ sources. The properties of this postsynaptic Ca2+signal can explain several features of LTD, such as its associativity, synapse specificity, and dependence on thetiming of synaptic activity, and can account for the slow kinetics of LTD expression. Thus, from a Ca2+ signaling perspective, LTD is one of the best understood forms of synaptic plasticity.
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Contestabile A. Role of nitric oxide in cerebellar development and function: focus on granule neurons. THE CEREBELLUM 2012; 11:50-61. [PMID: 21104176 DOI: 10.1007/s12311-010-0234-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
More than 20 years of research have firmly established important roles of the diffusible messenger molecule, nitric oxide (NO), in cerebellar development and function. Granule neurons are main players in every NO-related mechanism involving cerebellar function and dysfunction. Granule neurons are endowed with remarkable amounts of the Ca(2+)-dependent neuronal isoform of nitric oxide synthase and can directly respond to endogenously produced NO or induce responses in neighboring cells taking advantage of the high diffusibility of the molecule. Nitric oxide acts as a negative regulator of granule cell precursor proliferation and promotes survival and differentiation of these neurons. Nitric oxide is neuroprotective towards granule neurons challenged with toxic insults. Nitric oxide is a main regulator of bidirectional plasticity at parallel fiber-Purkinje neuron synapses, inducing long-term depression (LTD) or long-term potentiation (LTP) depending on postsynaptic Ca(2+) levels, thus playing a central role in cerebellar learning related to motor control. Granule neurons cooperate with glial cells, in particular with microglia, in the regulation of NO production through the respective forms of NOS present in the two cellular types. Aim of the present paper is to review the state of the art and the improvement of our understanding of NO functions in cerebellar granule neurons obtained during the last two decades and to outline possible future development of the research.
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Affiliation(s)
- Antonio Contestabile
- Department of Biology, University of Bologna, Via Selmi 3, 40126 Bologna, Italy.
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Sharov V, Pal R, Dremina E, Michaelis E, Schöneich C. Fluorogenic tagging of protein 3-nitrotyrosine with 4-(aminomethyl)benzene sulfonate in tissues: a useful alternative to Immunohistochemistry for fluorescence microscopy imaging of protein nitration. Free Radic Biol Med 2012; 53:1877-85. [PMID: 22995636 PMCID: PMC3523807 DOI: 10.1016/j.freeradbiomed.2012.08.582] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2012] [Revised: 08/22/2012] [Accepted: 08/23/2012] [Indexed: 01/01/2023]
Abstract
Protein tyrosine nitration is a common biomarker of biological aging and diverse pathologies associated with the excessive formation of reactive oxygen and nitrogen species. Recently, we suggested a novel fluorogenic derivatization procedure for the detection of 3-nitrotyrosine (3-NT) using benzylamine derivatives to convert specifically protein- or peptide-bound 3-NT to a highly fluorescent benzoxazole product. In this study, we applied this procedure to fluorogenic derivatization of protein 3-NT in sections from adult rat cerebellum to: (i) test this method for imaging nitrated proteins in fixed brain tissue sections and (ii) compare the chemical approach to immunohistochemical labeling with anti-3-NT antibodies. Immunofluorescence analysis of cerebellar sections using anti-3-NT antibodies showed differential levels of immunostaining in the molecular, Purkinje, and granule cell layers of the cerebellar cortex; in agreement with previous reports, the Purkinje cells were most highly labeled. Importantly, fluorogenic derivatization reactions of cerebellar proteins with 4-(aminomethyl)benzene sulfonic acid (ABS) and K(3)Fe(CN)(6) at pH 9, after sodium dithionite reduction of 3-NT to 3-aminotyrosine, showed a very similar pattern of relative intensity of cell labeling and improved resolution compared with antibody labeling. Our data demonstrate that ABS derivatization may be either a useful alternative to or a complementary approach to immunolabeling in imaging protein nitration in cells and tissues, including under conditions of dual labeling with antibodies to cell proteins, thus allowing for cellular colocalization of nitrated proteins and any protein of interest.
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Affiliation(s)
- V.S. Sharov
- Department of Pharmaceutical Chemistry, University of Kansas, 2095 Constant Avenue, Lawrence, KS 66047, USA
| | - R. Pal
- Department of Pharmacology and Toxicology, University of Kansas, 2095 Constant Avenue, Lawrence, KS 66047, USA
| | - E.S. Dremina
- Department of Pharmaceutical Chemistry, University of Kansas, 2095 Constant Avenue, Lawrence, KS 66047, USA
| | - E.K. Michaelis
- Department of Pharmacology and Toxicology, University of Kansas, 2095 Constant Avenue, Lawrence, KS 66047, USA
| | - C. Schöneich
- Department of Pharmaceutical Chemistry, University of Kansas, 2095 Constant Avenue, Lawrence, KS 66047, USA
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17
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Effects of nitric oxide on the survival and neuritogenesis of cerebellar Purkinje neurons. J Mol Neurosci 2011; 46:336-42. [PMID: 21728061 DOI: 10.1007/s12031-011-9590-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 06/22/2011] [Indexed: 01/21/2023]
Abstract
Nitric oxide has been investigated widely both during neurodevelopment and in neurological diseases. However, whilst it has been established that nitric oxide-producing enzymes of nitric oxide synthase family are expressed in cerebellar Purkinje neurons, the effects of nitric oxide on the viability and morphology of these neurons remain unknown. Here, we have demonstrated that the activity of neuronal nitric oxide synthase, but not the inducible or endothelial forms of this enzyme, is required to support the survival of a proportion of cerebellar Purkinje neurons in vitro. We discovered that donation of high concentrations of exogenous nitric oxide reduces Purkinje neuron survival in culture and that peroxynitrite is also toxic to these cells. Finally, we demonstrated that exogenous nitric oxide and peroxynitrite reduce both the magnitude and the complexity of the neurite arbour extended by cerebellar Purkinje neurons. Taken together, these findings reveal that whilst a low level of endogenous nitric oxide, released by the activity of neuronal nitric oxide synthase, is beneficial to cerebellar Purkinje neurons in vitro, high levels of exogenous nitric oxide and peroxynitrite are detrimental to both the survival of these neurons and to their ability to extend processes and form functional neural networks.
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18
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Goto JI, Mikoshiba K. Inositol 1,4,5-Trisphosphate Receptor-Mediated Calcium Release in Purkinje Cells: From Molecular Mechanism to Behavior. THE CEREBELLUM 2011; 10:820-33. [DOI: 10.1007/s12311-011-0270-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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19
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Steinert JR, Chernova T, Forsythe ID. Nitric oxide signaling in brain function, dysfunction, and dementia. Neuroscientist 2011; 16:435-52. [PMID: 20817920 DOI: 10.1177/1073858410366481] [Citation(s) in RCA: 315] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Nitric oxide (NO) is an important signaling molecule that is widely used in the nervous system. With recognition of its roles in synaptic plasticity (long-term potentiation, LTP; long-term depression, LTD) and elucidation of calcium-dependent, NMDAR-mediated activation of neuronal nitric oxide synthase (nNOS), numerous molecular and pharmacological tools have been used to explore the physiology and pathological consequences for nitrergic signaling. In this review, the authors summarize the current understanding of this subtle signaling pathway, discuss the evidence for nitrergic modulation of ion channels and homeostatic modulation of intrinsic excitability, and speculate about the pathological consequences of spillover between different nitrergic compartments in contributing to aberrant signaling in neurodegenerative disorders. Accumulating evidence points to various ion channels and particularly voltage-gated potassium channels as signaling targets, whereby NO mediates activity-dependent control of intrinsic neuronal excitability; such changes could underlie broader mechanisms of synaptic plasticity across neuronal networks. In addition, the inability to constrain NO diffusion suggests that spillover from endothelium (eNOS) and/or immune compartments (iNOS) into the nervous system provides potential pathological sources of NO and where control failure in these other systems could have broader neurological implications. Abnormal NO signaling could therefore contribute to a variety of neurodegenerative pathologies such as stroke/excitotoxicity, Alzheimer's disease, multiple sclerosis, and Parkinson's disease.
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Affiliation(s)
- Joern R Steinert
- Neurotoxicity at the Synaptic Interface, MRC Toxicology Unit, University of Leicester, Leicester, UK
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20
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Cerebellar Internal Models: Implications for the Dexterous Use of Tools. THE CEREBELLUM 2010; 11:325-35. [PMID: 21181462 DOI: 10.1007/s12311-010-0241-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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21
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Manninen T, Hituri K, Kotaleski JH, Blackwell KT, Linne ML. Postsynaptic signal transduction models for long-term potentiation and depression. Front Comput Neurosci 2010; 4:152. [PMID: 21188161 PMCID: PMC3006457 DOI: 10.3389/fncom.2010.00152] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 11/22/2010] [Indexed: 01/01/2023] Open
Abstract
More than a hundred biochemical species, activated by neurotransmitters binding to transmembrane receptors, are important in long-term potentiation (LTP) and long-term depression (LTD). To investigate which species and interactions are critical for synaptic plasticity, many computational postsynaptic signal transduction models have been developed. The models range from simple models with a single reversible reaction to detailed models with several hundred kinetic reactions. In this study, more than a hundred models are reviewed, and their features are compared and contrasted so that similarities and differences are more readily apparent. The models are classified according to the type of synaptic plasticity that is modeled (LTP or LTD) and whether they include diffusion or electrophysiological phenomena. Other characteristics that discriminate the models include the phase of synaptic plasticity modeled (induction, expression, or maintenance) and the simulation method used (deterministic or stochastic). We find that models are becoming increasingly sophisticated, by including stochastic properties, integrating with electrophysiological properties of entire neurons, or incorporating diffusion of signaling molecules. Simpler models continue to be developed because they are computationally efficient and allow theoretical analysis. The more complex models permit investigation of mechanisms underlying specific properties and experimental verification of model predictions. Nonetheless, it is difficult to fully comprehend the evolution of these models because (1) several models are not described in detail in the publications, (2) only a few models are provided in existing model databases, and (3) comparison to previous models is lacking. We conclude that the value of these models for understanding molecular mechanisms of synaptic plasticity is increasing and will be enhanced further with more complete descriptions and sharing of the published models.
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Affiliation(s)
- Tiina Manninen
- Department of Signal Processing, Tampere University of Technology Tampere, Finland
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22
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Baizer JS, Broussard DM. Expression of calcium-binding proteins and nNOS in the human vestibular and precerebellar brainstem. J Comp Neurol 2010; 518:872-95. [PMID: 20058225 DOI: 10.1002/cne.22250] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Information about the position and movement of the head in space is coded by vestibular receptors and relayed to four nuclei that comprise the vestibular nuclear complex (VNC). Many additional brainstem nuclei are involved in the processing of vestibular information, receiving signals either directly from the eighth nerve or indirectly via projections from the VNC. In cats, squirrel monkeys, and macaque monkeys, we found neurochemically defined subdivisions within the medial vestibular nucleus (MVe) and within the functionally related nucleus prepositus hypoglossi (PrH). In humans, different studies disagree about the borders, sizes, and possible subdivisions of the vestibular brainstem. In an attempt to clarify this organization, we have begun an analysis of the neurochemical characteristics of the human using brains from the Witelson Normal Brain Collection and standard techniques for antigen retrieval and immunohistochemistry. Using antibodies to calbindin, calretinin, parvalbumin, and nitric oxide synthase, we find neurochemically defined subdivisions within the MVe similar to the subdivisions described in cats and monkeys. The neurochemical organization of PrH is different. We also find unique neurochemical profiles for several structures that suggest reclassification of nuclei. These data suggest both quantitative and qualitative differences among cats, monkeys, and humans in the organization of the vestibular brainstem. These results have important implications for the analysis of changes in that organization subsequent to aging, disease, or loss of input.
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Affiliation(s)
- Joan S Baizer
- Department of Physiology and Biophysics, University at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, New York 14214-3078, USA.
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23
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Nitric oxide neurons and neurotransmission. Prog Neurobiol 2010; 90:246-55. [DOI: 10.1016/j.pneurobio.2009.10.007] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2008] [Revised: 04/22/2009] [Accepted: 10/09/2009] [Indexed: 11/24/2022]
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24
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Kitagawa Y, Hirano T, Kawaguchi SY. Prediction and validation of a mechanism to control the threshold for inhibitory synaptic plasticity. Mol Syst Biol 2009; 5:280. [PMID: 19536203 PMCID: PMC2710870 DOI: 10.1038/msb.2009.39] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2008] [Accepted: 05/14/2009] [Indexed: 11/09/2022] Open
Abstract
Synaptic plasticity, neuronal activity-dependent sustained alteration of the efficacy of synaptic transmission, underlies learning and memory. Activation of positive-feedback signaling pathways by an increase in intracellular Ca2+ concentration ([Ca2+]i) has been implicated in synaptic plasticity. However, the mechanism that determines the [Ca2+]i threshold for inducing synaptic plasticity is elusive. Here, we developed a kinetic simulation model of inhibitory synaptic plasticity in the cerebellum, and systematically analyzed the behavior of intricate molecular networks composed of protein kinases, phosphatases, etc. The simulation showed that Ca2+/calmodulin-dependent protein kinase II (CaMKII), which is essential for the induction of synaptic plasticity, was persistently activated or suppressed in response to different combinations of stimuli. The sustained CaMKII activation depended on synergistic actions of two positive-feedback reactions, CaMKII autophosphorylation and CaMKII-mediated inhibition of a CaM-dependent phosphodiesterase, PDE1. The simulation predicted that PDE1-mediated feedforward inhibition of CaMKII predominantly controls the Ca2+ threshold, which was confirmed by electrophysiological experiments in primary cerebellar cultures. Thus, combined application of simulation and experiments revealed that the Ca2+ threshold for the cerebellar inhibitory synaptic plasticity is primarily determined by PDE1.
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Affiliation(s)
- Yuichi Kitagawa
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, Japan
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25
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Kawato M. From 'understanding the brain by creating the brain' towards manipulative neuroscience. Philos Trans R Soc Lond B Biol Sci 2008; 363:2201-14. [PMID: 18375374 DOI: 10.1098/rstb.2008.2272] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Ten years have passed since the Japanese 'Century of the Brain' was promoted, and its most notable objective, the unique 'creating the brain' approach, has led us to apply a humanoid robot as a neuroscience tool. Here, we aim to understand the brain to the extent that we can make humanoid robots solve tasks typically solved by the human brain by essentially the same principles. I postulate that this 'Understanding the Brain by Creating the Brain' approach is the only way to fully understand neural mechanisms in a rigorous sense. Several humanoid robots and their demonstrations are introduced. A theory of cerebellar internal models and a systems biology model of cerebellar synaptic plasticity is discussed. Both models are experimentally supported, but the latter is more easily verifiable while the former is still controversial. I argue that the major reason for this difference is that essential information can be experimentally manipulated in molecular and cellular neuroscience while it cannot be manipulated at the system level. I propose a new experimental paradigm, manipulative neuroscience, to overcome this difficulty and allow us to prove cause-and-effect relationships even at the system level.
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Affiliation(s)
- Mitsuo Kawato
- ATR Computational Neuroscience Laboratories, Kyoto 619-0288, Japan.
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26
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Abstract
Despite similar computational approaches, there is surprisingly little interaction between the computational neuroscience and the systems biology research communities. In this review I reconstruct the history of the two disciplines and show that this may explain why they grew up apart. The separation is a pity, as both fields can learn quite a bit from each other. Several examples are given, covering sociological, software technical, and methodological aspects. Systems biology is a better organized community which is very effective at sharing resources, while computational neuroscience has more experience in multiscale modeling and the analysis of information processing by biological systems. Finally, I speculate about how the relationship between the two fields may evolve in the near future.
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Affiliation(s)
- Erik De Schutter
- Computational Neuroscience Unit, Okinawa Institute of Science and Technology, Japan.
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27
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Tanaka K, Khiroug L, Santamaria F, Doi T, Ogasawara H, Ellis-Davies GCR, Kawato M, Augustine GJ. Ca2+ requirements for cerebellar long-term synaptic depression: role for a postsynaptic leaky integrator. Neuron 2007; 54:787-800. [PMID: 17553426 DOI: 10.1016/j.neuron.2007.05.014] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Revised: 03/30/2007] [Accepted: 05/16/2007] [Indexed: 11/23/2022]
Abstract
Photolysis of a caged Ca(2+) compound was used to characterize the dependence of cerebellar long-term synaptic depression (LTD) on postsynaptic Ca(2+) concentration ([Ca(2+)](i)). Elevating [Ca(2+)](i) was sufficient to induce LTD without requiring any of the other signals produced by synaptic activity. A sigmoidal relationship between [Ca(2+)](i) and LTD indicated a highly cooperative triggering of LTD by Ca(2+). The duration of the rise in [Ca(2+)](i) influenced the apparent Ca(2+) affinity of LTD, and this time-dependent behavior could be described by a leaky integrator process with a time constant of 0.6 s. A computational model, based on a positive-feedback cycle that includes protein kinase C and MAP kinase, was capable of simulating these properties of Ca(2+)-triggered LTD. Disrupting this cycle experimentally also produced the predicted changes in the Ca(2+) dependence of LTD. We conclude that LTD arises from a mechanism that integrates postsynaptic Ca(2+) signals and that this integration may be produced by the positive-feedback cycle.
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Affiliation(s)
- Keiko Tanaka
- Department of Neurobiology, Duke University Medical Center, Box 3209, Durham, NC 27710, USA
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