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Dahleh MMM, Mello CF, Ferreira J, Rubin MA, Prigol M, Guerra GP. CaMKIIα mediates spermidine-induced memory enhancement in rats: A potential involvement of PKA/CREB pathway. Pharmacol Biochem Behav 2024; 240:173774. [PMID: 38648866 DOI: 10.1016/j.pbb.2024.173774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 04/17/2024] [Accepted: 04/17/2024] [Indexed: 04/25/2024]
Abstract
Memory consolidation is associated with the regulation of protein kinases, which impact synaptic functions and promote synaptogenesis. The administration of spermidine (SPD) has been shown to modulate major protein kinases associated with memory improvement, including the Ca2+-dependent protein kinase (PKC) and cAMP-dependent protein kinase (PKA), key players in the cAMP response element-binding protein (CREB) activation. Nevertheless, the initial mechanism underlying SPD-mediated memory consolidation remains unknown, as we hypothesize a potential involvement of the memory consolidation precursor, Ca2+/calmodulin-dependent protein kinase II-α (CaMKIIα), in this process. Based on this, our study aimed to investigate potential interactions among PKC, PKA, and CREB activation, mediated by CaMKIIα activation, in order to elucidate the SPD memory consolidation pathway. Our findings suggest that the post-training administration of the CaMKII inhibitor, KN-62 (0.25 nmol, intrahippocampal), prevented the memory enhancement induced by SPD (0.2 nmol, intrahippocampal) in the inhibitory avoidance task. Through western immunoblotting, we observed that phosphorylation of CaMKIIα in the hippocampus was facilitated 15 min after intrahippocampal SPD administration, resulting in the activation of PKA and CREB, 180 min after infusion, suggesting a possible sequential mechanism, since SPD with KN-62 infusion leads to a downregulation in CaMKIIα/PKA/CREB pathway. However, KN-62 does not alter the memory-facilitating effect of SPD on PKC, possibly demonstrating a parallel cascade in memory acquisition via PKA, without modulating CAMKIIα. These results suggest that memory enhancement induced by SPD administration involves crosstalk between CaMKIIα and PKA/CREB, with no PKC interaction.
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Affiliation(s)
- Mustafa Munir Mustafa Dahleh
- Laboratório de Avaliações Farmacológicas e Toxicológicas Aplicadas às Moléculas Bioativas - LaftamBio, Universidade Federal do Pampa - Campus Itaqui, 97650-000, Itaqui, RS, Brazil
| | - Carlos Fernando Mello
- Departamento de Fisiologia e Farmacologia, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Santa Maria, RS, 97105-900, Brazil
| | - Juliano Ferreira
- Departamento de Farmacologia, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Maribel Antonello Rubin
- Programa de Pós Graduação em Ciências Biológicas: Bioquímica Toxicológica, Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas, Laboratório de Neuropsicofarmacologia Universidade Federal de Santa Maria, Santa Maria, Brazil
| | - Marina Prigol
- Laboratório de Avaliações Farmacológicas e Toxicológicas Aplicadas às Moléculas Bioativas - LaftamBio, Universidade Federal do Pampa - Campus Itaqui, 97650-000, Itaqui, RS, Brazil
| | - Gustavo Petri Guerra
- Laboratório de Avaliações Farmacológicas e Toxicológicas Aplicadas às Moléculas Bioativas - LaftamBio, Universidade Federal do Pampa - Campus Itaqui, 97650-000, Itaqui, RS, Brazil.
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Rodrigues YE, Tigaret CM, Marie H, O'Donnell C, Veltz R. A stochastic model of hippocampal synaptic plasticity with geometrical readout of enzyme dynamics. eLife 2023; 12:e80152. [PMID: 37589251 PMCID: PMC10435238 DOI: 10.7554/elife.80152] [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: 05/10/2022] [Accepted: 03/22/2023] [Indexed: 08/18/2023] Open
Abstract
Discovering the rules of synaptic plasticity is an important step for understanding brain learning. Existing plasticity models are either (1) top-down and interpretable, but not flexible enough to account for experimental data, or (2) bottom-up and biologically realistic, but too intricate to interpret and hard to fit to data. To avoid the shortcomings of these approaches, we present a new plasticity rule based on a geometrical readout mechanism that flexibly maps synaptic enzyme dynamics to predict plasticity outcomes. We apply this readout to a multi-timescale model of hippocampal synaptic plasticity induction that includes electrical dynamics, calcium, CaMKII and calcineurin, and accurate representation of intrinsic noise sources. Using a single set of model parameters, we demonstrate the robustness of this plasticity rule by reproducing nine published ex vivo experiments covering various spike-timing and frequency-dependent plasticity induction protocols, animal ages, and experimental conditions. Our model also predicts that in vivo-like spike timing irregularity strongly shapes plasticity outcome. This geometrical readout modelling approach can be readily applied to other excitatory or inhibitory synapses to discover their synaptic plasticity rules.
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Affiliation(s)
- Yuri Elias Rodrigues
- Université Côte d’AzurNiceFrance
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), CNRSValbonneFrance
- Inria Center of University Côte d’Azur (Inria)Sophia AntipolisFrance
| | - Cezar M Tigaret
- Neuroscience and Mental Health Research Innovation Institute, Division of Psychological Medicine and Clinical Neurosciences,School of Medicine, Cardiff UniversityCardiffUnited Kingdom
| | - Hélène Marie
- Université Côte d’AzurNiceFrance
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), CNRSValbonneFrance
| | - Cian O'Donnell
- School of Computing, Engineering, and Intelligent Systems, Magee Campus, Ulster UniversityLondonderryUnited Kingdom
- School of Computer Science, Electrical and Electronic Engineering, and Engineering Mathematics, University of BristolBristolUnited Kingdom
| | - Romain Veltz
- Inria Center of University Côte d’Azur (Inria)Sophia AntipolisFrance
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A Modeling and Analysis Study Reveals That CaMKII in Synaptic Plasticity Is a Dominant Affecter in CaM Systems in a T286 Phosphorylation-Dependent Manner. Molecules 2022; 27:molecules27185974. [PMID: 36144710 PMCID: PMC9501549 DOI: 10.3390/molecules27185974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/18/2022] [Accepted: 08/25/2022] [Indexed: 11/17/2022] Open
Abstract
NMDAR-dependent synaptic plasticity in the hippocampus consists of two opposing forces: long-term potentiation (LTP), which strengthens synapses and long-term depression (LTD), which weakens synapses. LTP and LTD are associated with memory formation and loss, respectively. Synaptic plasticity is controlled at a molecular level by Ca2+-mediated protein signaling. Here, Ca2+ binds the protein, calmodulin (CaM), which modulates synaptic plasticity in both directions. This is because Ca2+-bound CaM activates both LTD-and LTP-inducing proteins. Understanding how CaM responds to Ca2+ signaling and how this translates into synaptic plasticity is therefore important to understanding synaptic plasticity induction. In this paper, CaM activation by Ca2+ and calmodulin binding to downstream proteins was mathematically modeled using differential equations. Simulations were monitored with and without theoretical knockouts and, global sensitivity analyses were performed to determine how Ca2+/CaM signaling occurred at various Ca2+ signals when CaM levels were limiting. At elevated stimulations, the total CaM pool rapidly bound to its protein binding targets which regulate both LTP and LTD. This was followed by CaM becoming redistributed from low-affinity to high-affinity binding targets. Specifically, CaM was redistributed away from LTD-inducing proteins to bind the high-affinity LTP-inducing protein, calmodulin-dependent kinase II (CaMKII). In this way, CaMKII acted as a dominant affecter and repressed activation of opposing CaM-binding protein targets. The model thereby showed a novel form of CaM signaling by which the two opposing pathways crosstalk indirectly. The model also found that CaMKII can repress cAMP production by repressing CaM-regulated proteins, which catalyze cAMP production. The model also found that at low Ca2+ stimulation levels, typical of LTD induction, CaM signaling was unstable and is therefore unlikely to alone be enough to induce synaptic depression. Overall, this paper demonstrates how limiting levels of CaM may be a fundamental aspect of Ca2+ regulated signaling which allows crosstalk among proteins without requiring directly interaction.
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4
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Qian Y, Xia T, Cui Y, Chu S, Ma Z, Gu X. The role of CaMKII in neuropathic pain and fear memory in chronic constriction injury in rats. Int J Neurosci 2018; 129:146-154. [PMID: 30118368 DOI: 10.1080/00207454.2018.1512986] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Yue Qian
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Medical School of Nanjing University. Nanjing, P.R. China
| | - Tianjiao Xia
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Medical School of Nanjing University. Nanjing, P.R. China
- Medical School of Nanjing University. Nanjing, P.R. China
| | - Yin Cui
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Medical School of Nanjing University. Nanjing, P.R. China
| | - Shuaishuai Chu
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Medical School of Nanjing University. Nanjing, P.R. China
| | - Zhengliang Ma
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Medical School of Nanjing University. Nanjing, P.R. China
| | - Xiaoping Gu
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Medical School of Nanjing University. Nanjing, P.R. China
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Xiong L, Meng Q, Sun X, Lu X, Fu Q, Peng Q, Yang J, Oh KW, Hu Z. Cocaine- and amphetamine-regulated transcript peptide in the nucleus accumbens shell inhibits cocaine-induced locomotor sensitization to transient over-expression of α-Ca 2+ /calmodulin-dependent protein kinase II. J Neurochem 2018; 146:289-303. [PMID: 29313985 DOI: 10.1111/jnc.14289] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Revised: 12/15/2017] [Accepted: 12/18/2017] [Indexed: 11/29/2022]
Abstract
Cocaine- and amphetamine-regulated transcript (CART) peptide is a widely distributed neurotransmitter that attenuates cocaine-induced locomotor activity when injected into the nucleus accumbens (NAc). Our previous work first confirmed that the inhibitory mechanism of the CART peptide on cocaine-induced locomotor activity is related to a reduction in cocaine-enhanced phosphorylated Ca2+ /calmodulin-dependent protein kinaseIIα (pCaMKIIα) and the enhancement of cocaine-induced D3R function. This study investigated whether CART peptide inhibited cocaine-induced locomotor activity via inhibition of interactions between pCaMKIIα and the D3 dopamine receptor (D3R). We demonstrated that lentivirus-mediated gene transfer transiently increased pCaMKIIα expression, which peaked at 10 days after microinjection into the rat NAc shell, and induced a significant increase in Ca2+ influx along with greater behavioral sensitivity in the open field test after intraperitoneal injections of cocaine (15 mg/kg). However, western blot analysis and coimmunoprecipitation demonstrated that CART peptide treatment in lentivirus-transfected CaMKIIα-over-expressing NAc rat tissues or cells prior to cocaine administration inhibited the cocaine-induced Ca2+ influx and attenuated the cocaine-increased pCaMKIIα expression in lentivirus-transfected CaMKIIα-over-expressing cells. CART peptide decreased the cocaine-enhanced phosphorylated cAMP response element binding protein (pCREB) expression via inhibition of the pCaMKIIα-D3R interaction, which may account for the prolonged locomotor sensitization induced by repeated cocaine treatment in lentivirus-transfected CaMKIIα-over-expressing cells. These results provide strong evidence for the inhibitory modulation of CART peptide in cocaine-induced locomotor sensitization. Cover Image for this issue: doi: 10.1111/jnc.14187.
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Affiliation(s)
- Lixia Xiong
- Department of Pathophysiology, College of Basic Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Qing Meng
- Queen Mary Institute, School of Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Xi Sun
- Anhui Sinobioway Cell Therapy CO., LTD, Hefei, Anhui, China
| | - Xiangtong Lu
- Department of Pathophysiology, College of Basic Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Qiang Fu
- Department of Respiration, The Fourth Affiliated Hospital, Nanchang University, Nanchang, Jiangxi, China.,Department of Respiration, Department Two, Jiangxi Provincial People's Hospital, Nanchang, Jiangxi, China
| | - Qinghua Peng
- Department of Anesthesiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi, China
| | - Jianhua Yang
- Department of Physiology, College of Basic Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Ki-Wan Oh
- College of Pharmacy, Chungbuk National University, Cheongju, Korea
| | - Zhenzhen Hu
- Department of Pathophysiology, College of Basic Medicine, Nanchang University, Nanchang, Jiangxi, China.,Jiangxi Province Key laboratory of Tumor Pathogens and Molecular Pathology and the Department of Pathology, Schools of Basic Medical Sciences and Pharmaceutical Sciences, Nanchang University Medical College, Nanchang, China
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Wei N, Dong YT, Deng J, Wang Y, Qi XL, Yu WF, Xiao Y, Zhou JJ, Guan ZZ. Changed expressions of N-methyl-d-aspartate receptors in the brains of rats and primary neurons exposed to high level of fluoride. J Trace Elem Med Biol 2018; 45:31-40. [PMID: 29173480 DOI: 10.1016/j.jtemb.2017.09.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 09/15/2017] [Accepted: 09/19/2017] [Indexed: 11/26/2022]
Abstract
Expressions of N-methyl-d-aspartic acid receptors (NMDARs) in the brains of rats and primary neurons exposed to high fluoride were investigated. Sprague-Dawley rats were divided randomly into a fluorosis group (50ppm fluoride in the drinking water for 6 months) and controls (<0.5ppm fluoride) and the offspring from these rats sacrificed on postnatal days 1, 7, 14, 21 and 28. The primary cultured neurons from the hippocampus of neonatal rats were treated with 5 and 50ppm fluoride for 48h. NMDAR subunits at protein or mRNA levels were quantified by Western blotting or real-time PCR. The phosphorylated calmodulin-protein kinase II (CaMKII) was determined by Western blotting, concentration of Ca2+ in neurons by laser confocal microscopy and apoptosis by flow cytometry. In the brains of adult rats and pups as well as in primary neurons exposed to high fluoride, the mRNAs encoding GluN1 and GluN2B subunits and the corresponding proteins were elevated, the GluN3A lowered and the GluN2A unchanged. In addition, the level of phosphor-CaMKII was reduced, and Ca2+ influx and apoptosis enhanced in the brains of rats and cultured neurons exposed to high fluoride. The results indicate that such modifications may involve brain damage induced by chronic fluorosis.
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Affiliation(s)
- Na Wei
- Department of Pathology in the Affiliated Hospital of Guizhou Medical University, PR China
| | - Yang-Ting Dong
- Department of Pathology in the Affiliated Hospital of Guizhou Medical University, PR China
| | - Jie Deng
- Department of Pathology in the Affiliated Hospital of Guizhou Medical University, PR China; Key Laboratory of Medical Molecular Biology (Guizhou Medical University), Guizhou Province, PR China
| | - Ya Wang
- Department of Pathology in the Affiliated Hospital of Guizhou Medical University, PR China
| | - Xiao-Lan Qi
- Key Laboratory of Endemic and Ethnic Diseases (Guizhou Medical University), Ministry of Education, PR China; Key Laboratory of Medical Molecular Biology (Guizhou Medical University), Guizhou Province, PR China
| | - Wen-Feng Yu
- Key Laboratory of Endemic and Ethnic Diseases (Guizhou Medical University), Ministry of Education, PR China; Key Laboratory of Medical Molecular Biology (Guizhou Medical University), Guizhou Province, PR China
| | - Yan Xiao
- Key Laboratory of Endemic and Ethnic Diseases (Guizhou Medical University), Ministry of Education, PR China; Key Laboratory of Medical Molecular Biology (Guizhou Medical University), Guizhou Province, PR China
| | - Jian-Jiang Zhou
- Key Laboratory of Endemic and Ethnic Diseases (Guizhou Medical University), Ministry of Education, PR China; Key Laboratory of Medical Molecular Biology (Guizhou Medical University), Guizhou Province, PR China
| | - Zhi-Zhong Guan
- Department of Pathology in the Affiliated Hospital of Guizhou Medical University, PR China; Key Laboratory of Endemic and Ethnic Diseases (Guizhou Medical University), Ministry of Education, PR China; Key Laboratory of Medical Molecular Biology (Guizhou Medical University), Guizhou Province, PR China.
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Liang J, Kulasiri D, Samarasinghe S. Computational investigation of Amyloid-β-induced location- and subunit-specific disturbances of NMDAR at hippocampal dendritic spine in Alzheimer's disease. PLoS One 2017; 12:e0182743. [PMID: 28837653 PMCID: PMC5570373 DOI: 10.1371/journal.pone.0182743] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Accepted: 07/24/2017] [Indexed: 01/22/2023] Open
Abstract
In Alzheimer’s disease (AD), dysregulation of intracellular Ca2+ signalling has been observed as an early event prior to the presence of clinical symptoms and is believed to be a crucial factor contributing to AD pathogenesis. Amyloid-β oligomers (AβOs) disturb the N-methyl-D-aspartate receptor (NMDAR)-mediated postsynaptic Ca2+ signalling in response to presynaptic stimulation by increasing the availability of extracellular glutamate as well as directly disturbing the NMDARs. The abnormal Ca2+ response can further lead to impairments in long-term potentiation (LTP), an important process in memory formation. In this study, we develop a mathematical model of a CA1 pyramidal dendritic spine and conduct computational experiments. We use this model to mimic alterations by AβOs under AD conditions to investigate how they are involved in the Ca2+ dysregulation in the dendritic spine. The alterations in glutamate availability, as well as NMDAR availability and activity, are studied both individually and globally. The simulation results suggest that alterations in glutamate availability mostly affect the synaptic response and have limited effects on the extrasynaptic receptors. Moreover, overactivation of extrasynaptic NMDARs in AD is unlikely to be induced by presynaptic stimulation, but by upregulation of the resting level of glutamate, possibly resulting from these alterations. Furthermore, internalisation of synaptic NR2A-NMDAR shows greater damage to the postsynaptic Ca2+ response in comparison with the internalisation of NR2B-NMDARs; thus, the suggested neuroprotective role of the latter is very limited during synaptic transmission in AD. We integrate a CaMKII state transition model with the Ca2+ model to further study the effects of alterations of NMDARs in the CaMKII state transition, an important downstream event in the early phase of LTP. The model reveals that cooperation between NR2A- and NR2B-NMDAR is required for LTP induction. Under AD conditions, internalisation of membrane NMDARs is suggested to be the cause of the loss of synapse numbers by disrupting CaMKII-NMDAR formation.
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Affiliation(s)
- Jingyi Liang
- Centre for Advanced Computational Solutions (C-fACS), Lincoln University, Christchurch, New Zealand
| | - Don Kulasiri
- Centre for Advanced Computational Solutions (C-fACS), Lincoln University, Christchurch, New Zealand
- * E-mail:
| | - Sandhya Samarasinghe
- Centre for Advanced Computational Solutions (C-fACS), Lincoln University, Christchurch, New Zealand
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A Spiking Working Memory Model Based on Hebbian Short-Term Potentiation. J Neurosci 2017; 37:83-96. [PMID: 28053032 PMCID: PMC5214637 DOI: 10.1523/jneurosci.1989-16.2016] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 10/05/2016] [Accepted: 10/19/2016] [Indexed: 11/26/2022] Open
Abstract
A dominant theory of working memory (WM), referred to as the persistent activity hypothesis, holds that recurrently connected neural networks, presumably located in the prefrontal cortex, encode and maintain WM memory items through sustained elevated activity. Reexamination of experimental data has shown that prefrontal cortex activity in single units during delay periods is much more variable than predicted by such a theory and associated computational models. Alternative models of WM maintenance based on synaptic plasticity, such as short-term nonassociative (non-Hebbian) synaptic facilitation, have been suggested but cannot account for encoding of novel associations. Here we test the hypothesis that a recently identified fast-expressing form of Hebbian synaptic plasticity (associative short-term potentiation) is a possible mechanism for WM encoding and maintenance. Our simulations using a spiking neural network model of cortex reproduce a range of cognitive memory effects in the classical multi-item WM task of encoding and immediate free recall of word lists. Memory reactivation in the model occurs in discrete oscillatory bursts rather than as sustained activity. We relate dynamic network activity as well as key synaptic characteristics to electrophysiological measurements. Our findings support the hypothesis that fast Hebbian short-term potentiation is a key WM mechanism. SIGNIFICANCE STATEMENT Working memory (WM) is a key component of cognition. Hypotheses about the neural mechanism behind WM are currently under revision. Reflecting recent findings of fast Hebbian synaptic plasticity in cortex, we test whether a cortical spiking neural network model with such a mechanism can learn a multi-item WM task (word list learning). We show that our model can reproduce human cognitive phenomena and achieve comparable memory performance in both free and cued recall while being simultaneously compatible with experimental data on structure, connectivity, and neurophysiology of the underlying cortical tissue. These findings are directly relevant to the ongoing paradigm shift in the WM field.
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Yang Q, Song D, Qing H. Neural changes in Alzheimer's disease from circuit to molecule: Perspective of optogenetics. Neurosci Biobehav Rev 2017; 79:110-118. [PMID: 28522119 DOI: 10.1016/j.neubiorev.2017.05.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 04/21/2017] [Accepted: 05/12/2017] [Indexed: 02/08/2023]
Abstract
Alzheimer's disease (AD), as a crucial neurodegenerative disorder, affects neural activities at many levels. Synaptic plasticity and neural circuits are most susceptible in AD, but the detailed mechanism is unclear. Optogenetic tools provide unprecedented spatio-temporal specificity to stimulate specific neural circuits or synaptic molecules to reveal the precise function of normal brain and mechanism of deficits in AD models. Furthermore, using optogenetics to stimulate neurons can rescue learning and memory loss caused by AD. It also has possibility to use light to control the Neurotransmitter receptors and their downstream signal pathway. These technical methods have broad therapeutic application prospect.
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Affiliation(s)
- Qinghu Yang
- School of Life Science, Beijing Institute of Technology, Beijing 100081, PR China
| | - Da Song
- School of Life Science, Beijing Institute of Technology, Beijing 100081, PR China
| | - Hong Qing
- School of Life Science, Beijing Institute of Technology, Beijing 100081, PR China.
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Kulasiri D, Liang J, He Y, Samarasinghe S. Global sensitivity analysis of a model related to memory formation in synapses: Model reduction based on epistemic parameter uncertainties and related issues. J Theor Biol 2017; 419:116-136. [PMID: 28189671 DOI: 10.1016/j.jtbi.2017.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 01/30/2017] [Accepted: 02/04/2017] [Indexed: 11/28/2022]
Abstract
We investigate the epistemic uncertainties of parameters of a mathematical model that describes the dynamics of CaMKII-NMDAR complex related to memory formation in synapses using global sensitivity analysis (GSA). The model, which was published in this journal, is nonlinear and complex with Ca2+ patterns with different level of frequencies as inputs. We explore the effects of parameter on the key outputs of the model to discover the most sensitive ones using GSA and partial ranking correlation coefficient (PRCC) and to understand why they are sensitive and others are not based on the biology of the problem. We also extend the model to add presynaptic neurotransmitter vesicles release to have action potentials as inputs of different frequencies. We perform GSA on this extended model to show that the parameter sensitivities are different for the extended model as shown by PRCC landscapes. Based on the results of GSA and PRCC, we reduce the original model to a less complex model taking the most important biological processes into account. We validate the reduced model against the outputs of the original model. We show that the parameter sensitivities are dependent on the inputs and GSA would make us understand the sensitivities and the importance of the parameters. A thorough phenomenological understanding of the relationships involved is essential to interpret the results of GSA and hence for the possible model reduction.
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Affiliation(s)
- Don Kulasiri
- Centre for Advanced Computational Solutions (C-fACS), Molecular Biosciences Department, Lincoln University, Christchurch, New Zealand.
| | - Jingyi Liang
- Centre for Advanced Computational Solutions (C-fACS), Molecular Biosciences Department, Lincoln University, Christchurch, New Zealand
| | - Yao He
- Centre for Advanced Computational Solutions (C-fACS), Molecular Biosciences Department, Lincoln University, Christchurch, New Zealand
| | - Sandhya Samarasinghe
- Centre for Advanced Computational Solutions (C-fACS), Molecular Biosciences Department, Lincoln University, Christchurch, New Zealand
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