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Hagena H, Manahan-Vaughan D. Interplay of hippocampal long-term potentiation and long-term depression in enabling memory representations. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230229. [PMID: 38853558 DOI: 10.1098/rstb.2023.0229] [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: 01/08/2024] [Accepted: 05/07/2024] [Indexed: 06/11/2024] Open
Abstract
Hippocampal long-term potentiation (LTP) and long-term depression (LTD) are Hebbian forms of synaptic plasticity that are widely believed to comprise the physiological correlates of associative learning. They comprise a persistent, input-specific increase or decrease, respectively, in synaptic efficacy that, in rodents, can be followed for days and weeks in vivo. Persistent (>24 h) LTP and LTD exhibit distinct frequency-dependencies and molecular profiles in the hippocampal subfields. Moreover, causal and genetic studies in behaving rodents indicate that both LTP and LTD fulfil specific and complementary roles in the acquisition and retention of spatial memory. LTP is likely to be responsible for the generation of a record of spatial experience, which may serve as an associative schema that can be re-used to expedite or facilitate subsequent learning. In contrast, LTD may enable modification and dynamic updating of this representation, such that detailed spatial content information is included and the schema is rendered unique and distinguishable from other similar representations. Together, LTP and LTD engage in a dynamic interplay that supports the generation of complex associative memories that are resistant to generalization. This article is part of a discussion meeting issue 'Long-term potentiation: 50 years on'.
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Affiliation(s)
- Hardy Hagena
- Medical Faculty, Department of Neurophysiology, Ruhr University Bochum , Bochum 44780, Germany
| | - Denise Manahan-Vaughan
- Medical Faculty, Department of Neurophysiology, Ruhr University Bochum , Bochum 44780, Germany
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Hoang TH, Manahan-Vaughan D. Differentiated somatic gene expression is triggered in the dorsal hippocampus and the anterior retrosplenial cortex by hippocampal synaptic plasticity prompted by spatial content learning. Brain Struct Funct 2024; 229:639-655. [PMID: 37690045 PMCID: PMC10978647 DOI: 10.1007/s00429-023-02694-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 08/07/2023] [Indexed: 09/12/2023]
Abstract
Hippocampal afferent inputs, terminating on proximal and distal subfields of the cornus ammonis (CA), enable the functional discrimination of 'what' (item identity) and 'where' (spatial location) elements of a spatial representation. This kind of information is supported by structures such as the retrosplenial cortex (RSC). Spatial content learning promotes the expression of hippocampal synaptic plasticity, particularly long-term depression (LTD). In the CA1 region, this is specifically facilitated by the learning of item-place features of a spatial environment. Gene-tagging, by means of time-locked fluorescence in situ hybridization (FISH) to detect nuclear expression of immediate early genes, can reveal neuronal populations that engage in experience-dependent information encoding. In the current study, using FISH, we examined if learning-facilitated LTD results in subfield-specific information encoding in the hippocampus and RSC. Rats engaged in novel exploration of small items during stimulation of Schaffer collateral-CA1 synapses. This resulted in LTD (> 24 h). FISH, to detect nuclear expression of Homer1a, revealed that the distal-CA1 and proximal-CA3 subcompartments were particularly activated by this event. By contrast, all elements of the proximodistal cornus ammonis-axis showed equal nuclear Homer1a expression following LTD induction solely by means of afferent stimulation. The RSC exhibited stronger nuclear Homer1a expression in response to learning-facilitated LTD, and to novel item-place experience, compared to LTD induced by sole afferent stimulation in CA1. These results show that both the cornus ammonis and RSC engage in differentiated information encoding of item-place learning that is salient enough, in its own right, to drive the expression of hippocampal LTD. These results also reveal a novel role of the RSC in item-place learning.
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Affiliation(s)
- Thu-Huong Hoang
- Medical Faculty, Department of Neurophysiology, Ruhr University Bochum, Universitätsstr. 150, MA 4/150, 44780, Bochum, Germany
| | - Denise Manahan-Vaughan
- Medical Faculty, Department of Neurophysiology, Ruhr University Bochum, Universitätsstr. 150, MA 4/150, 44780, Bochum, Germany.
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Bijoch Ł, Klos J, Pękała M, Fiołna K, Kaczmarek L, Beroun A. Diverse processing of pharmacological and natural rewards by the central amygdala. Cell Rep 2023; 42:113036. [PMID: 37616162 DOI: 10.1016/j.celrep.2023.113036] [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: 02/17/2023] [Revised: 07/03/2023] [Accepted: 08/11/2023] [Indexed: 08/25/2023] Open
Abstract
The central amygdala (CeA) with its medial (CeM) and lateral (CeL) nuclei is the brain hub for processing stimuli with emotional context. CeL nucleus gives a strong inhibitory input to the CeM, and this local circuitry assigns values (positive or negative) to incoming stimuli, guiding appropriate behavior (approach or avoid). However, the particular involvement of CeA in processing such emotionally relevant information and adaptations of the CeA circuitry are not yet well understood. In this study, we examined synaptic plasticity in the CeA after exposure to two types of rewards, pharmacological (cocaine) and natural (sugar). We found that both rewards engage CeM, where they generate silent synapses resulting in the strengthening of the network. However, only cocaine triggers plasticity in the CeL, which leads to the weakening of its excitatory inputs. Finally, chemogenetic inhibition of CeM attenuates animal preference for sugar, while activation delays cocaine-induced increase in locomotor activity.
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Affiliation(s)
- Łukasz Bijoch
- Nencki-EMBL Center of Excellence for Neural Plasticity and Brain Disorders: BRAINCITY, Laboratory of Neuronal Plasticity, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, L. Pasteura 3, 02-093 Warsaw, Poland
| | - Joanna Klos
- Nencki-EMBL Center of Excellence for Neural Plasticity and Brain Disorders: BRAINCITY, Laboratory of Neuronal Plasticity, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, L. Pasteura 3, 02-093 Warsaw, Poland
| | - Martyna Pękała
- Nencki-EMBL Center of Excellence for Neural Plasticity and Brain Disorders: BRAINCITY, Laboratory of Neurobiology, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, L. Pasteura 3, 02-093 Warsaw, Poland
| | - Kristina Fiołna
- Nencki-EMBL Center of Excellence for Neural Plasticity and Brain Disorders: BRAINCITY, Laboratory of Neuronal Plasticity, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, L. Pasteura 3, 02-093 Warsaw, Poland; Nencki-EMBL Center of Excellence for Neural Plasticity and Brain Disorders: BRAINCITY, Laboratory of Neurobiology, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, L. Pasteura 3, 02-093 Warsaw, Poland
| | - Leszek Kaczmarek
- Nencki-EMBL Center of Excellence for Neural Plasticity and Brain Disorders: BRAINCITY, Laboratory of Neurobiology, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, L. Pasteura 3, 02-093 Warsaw, Poland
| | - Anna Beroun
- Nencki-EMBL Center of Excellence for Neural Plasticity and Brain Disorders: BRAINCITY, Laboratory of Neuronal Plasticity, Nencki Institute of Experimental Biology of the Polish Academy of Sciences, L. Pasteura 3, 02-093 Warsaw, Poland.
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Maltsev A, Roshchin M, Bezprozvanny I, Smirnov I, Vlasova O, Balaban P, Borodinova A. Bidirectional regulation by "star forces": Ionotropic astrocyte's optical stimulation suppresses synaptic plasticity, metabotropic one strikes back. Hippocampus 2023; 33:18-36. [PMID: 36484471 DOI: 10.1002/hipo.23486] [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: 07/06/2022] [Revised: 11/24/2022] [Accepted: 11/28/2022] [Indexed: 12/14/2022]
Abstract
The role of astrocytes in modulating synaptic plasticity is an important question that until recently was not addressed due to limitations of previously existing technology. In the present study, we took an advantage of optogenetics to specifically activate astrocytes in hippocampal slices in order to study effects on synaptic function. Using the AAV-based delivery strategy, we expressed the ionotropic channelrhodopsin-2 (ChR2) or the metabotropic Gq-coupled Opto-a1AR opsins specifically in hippocampal astrocytes to compare different modalities of astrocyte activation. In electrophysiological experiments, we observed a depression of basal field excitatory postsynaptic potentials (fEPSPs) in the CA1 hippocampal layer following light stimulation of astrocytic ChR2. The ChR2-mediated depression increased under simultaneous light and electrical theta-burst stimulation (TBS). Application of the type 2 purinergic receptor antagonist suramin prevented depression of basal synaptic transmission, and switched the ChR2-dependent depression into potentiation. The GABAB receptor antagonist, phaclofen, did not prevent the depression of basal fEPSPs, but switched the ChR2-dependent depression into potentiation comparable to the values for TBS in control slices. In contrast, light stimulation of Opto-a1AR expressed in astrocytes led to an increase in basal fEPSPs, as well as a potentiation of synaptic responses to TBS significantly. A specific blocker of the Gq protein downstream target, the phospholipase C, U73122, completely prevented the effects of Opto-a1AR stimulation on basal fEPSPs or Opto + TBS responses. To understand molecular basis for the observed effects, we performed an analysis of gene expression in these slices using quantitative PCR approach. We observed a significant upregulation of "immediate-early" gene expression in hippocampal slices after light activation of Opto-a1AR-expressing astrocytes alone (cRel, Arc, Fos, JunB, and Egr1) or paired with TBS (cRel, Fos, and Egr1). Activation of ChR2-expressing hippocampal astrocytes was insufficient to affect expression of these genes in our experimental conditions. Thus, we concluded that optostimulation of astrocytes with ChR2 and Opto-a1AR optogenetic tools enables bidirectional modulation of synaptic plasticity and gene expression in hippocampus.
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Affiliation(s)
- Alexander Maltsev
- Laboratory of Cellular Neurobiology of Learning, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
| | - Matvey Roshchin
- Laboratory of Cellular Neurobiology of Learning, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
| | - Ilya Bezprozvanny
- Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia.,Department of Physiology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Ivan Smirnov
- Laboratory of Cellular Neurobiology of Learning, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
| | - Olga Vlasova
- Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia
| | - Pavel Balaban
- Laboratory of Cellular Neurobiology of Learning, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
| | - Anastasia Borodinova
- Laboratory of Cellular Neurobiology of Learning, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
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Deibel SH, Higdon S, Cassell TTS, House-Denine ML, Giberson E, Webb IC, Thorpe CM. Impaired Morris water task retention following T21 light dark cycle exposure is not due to reduced hippocampal c-FOS expression. Front Behav Neurosci 2022; 16:1025388. [PMID: 36311860 PMCID: PMC9596763 DOI: 10.3389/fnbeh.2022.1025388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 09/09/2022] [Indexed: 11/21/2022] Open
Abstract
Circadian rhythms influence virtually all aspects of physiology and behavior. This is problematic when circadian rhythms no longer reliably predict time. Circadian rhythm disruption can impair memory, yet we don’t know how this fully works at the systems and molecular level. When trying to determine the root of a memory impairment, assessing neuronal activation with c-FOS is useful. This has yet to be assessed in the hippocampi of circadian rhythm disrupted rats in a hippocampal gold standard task. Rats were trained on the Morris water task (MWT), then received 6 days of a 21-h day (T21), 13 days of a normal light dark cycle, probe trial, and tissue extraction an hour later. Despite having impaired memory in the probe trial, compared to controls there were no differences in c-FOS expression in hippocampal sub regions: CA1; CA3; Dentate gyrus. These data confirm others in hamsters demonstrating that arrhythmicity which produces an impairment in spontaneous alternation does not affect c-FOS in the dentate gyrus. The current study indicates that the memory impairment induced by a lighting manipulation is likely not due to attenuated neuronal activation. Determining how the master clock in the brain communicates with the hippocampus is needed to untangle the relationship between circadian rhythms and memory.
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Affiliation(s)
- Scott H. Deibel
- Department of Psychology, University of New Brunswick, Fredericton, NB, Canada
- *Correspondence: Scott H. Deibel,
| | - S. Higdon
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - T. T. S. Cassell
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - M. L. House-Denine
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - E. Giberson
- Department of Psychology, University of New Brunswick, Fredericton, NB, Canada
| | - I. C. Webb
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - C. M. Thorpe
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, Canada
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Stacho M, Manahan-Vaughan D. The Intriguing Contribution of Hippocampal Long-Term Depression to Spatial Learning and Long-Term Memory. Front Behav Neurosci 2022; 16:806356. [PMID: 35548697 PMCID: PMC9084281 DOI: 10.3389/fnbeh.2022.806356] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 03/10/2022] [Indexed: 01/03/2023] Open
Abstract
Long-term potentiation (LTP) and long-term depression (LTD) comprise the principal cellular mechanisms that fulfill established criteria for the physiological correlates of learning and memory. Traditionally LTP, that increases synaptic weights, has been ascribed a prominent role in learning and memory whereas LTD, that decreases them, has often been relegated to the category of “counterpart to LTP” that serves to prevent saturation of synapses. In contradiction of these assumptions, studies over the last several years have provided functional evidence for distinct roles of LTD in specific aspects of hippocampus-dependent associative learning and information encoding. Furthermore, evidence of the experience-dependent “pruning” of excitatory synapses, the majority of which are located on dendritic spines, by means of LTD has been provided. In addition, reports exist of the temporal and physical restriction of LTP in dendritic compartments by means of LTD. Here, we discuss the role of LTD and LTP in experience-dependent information encoding based on empirical evidence derived from conjoint behavioral and electrophysiological studies conducted in behaving rodents. We pinpoint the close interrelation between structural modifications of dendritic spines and the occurrence of LTP and LTD. We report on findings that support that whereas LTP serves to acquire the general scheme of a spatial representation, LTD enables retention of content details. We argue that LTD contributes to learning by engaging in a functional interplay with LTP, rather than serving as its simple counterpart, or negator. We propose that similar spatial experiences that share elements of neuronal representations can be modified by means of LTD to enable pattern separation. Therewith, LTD plays a crucial role in the disambiguation of similar spatial representations and the prevention of generalization.
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Wang G, Luo P, Zhang S, Huang Q, Zhang S, Zeng Q, Mao J. Screening and Identification of Antidepressant Active Ingredients from Puerariae Radix Extract and Study on Its Mechanism. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:2230195. [PMID: 34539968 PMCID: PMC8445728 DOI: 10.1155/2021/2230195] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 08/12/2021] [Accepted: 08/17/2021] [Indexed: 11/18/2022]
Abstract
Objective. Depression is a common mental disease with long course and high recurrence rate. Previous studies showed that Puerariae Radix and its extracts have powerful antidepressant effects in recent years. The study proposed an integrated strategy, combining network pharmacology and molecular pharmacology experiment to investigate the mechanisms of the antidepressant active ingredients from Puerariae Radix. Methods. TCMSP database, GeneCards database, Venny 2.1, UniProt database, STRING database, Cytoscape 3.7.2, and Metascape database were used to screen the active chemical components, antidepressant-related genes, and core targets, convert the abbreviated gene names in batch, search and predict the interaction between proteins, and construct the PPI network of Puerariae Radix. KEGG pathway and GO biological process enrichment and biological annotation were used to select antidepressant core gene targets. The MTT method was used to detect the effect of puerarin on the damage of PC12 cells induced by corticosterone. The DCFH-DA probe and ROS assay kit were utilized to detect the production of ROS in PC12 cells. PI/Annexin V was used to detect the apoptotic rate of puerarin on PC12 cells. Western blotting was used to verify the regulation of puerarin on the key targets of AKT1, FOS, CASP3, STAT3, and TNF-α in PC12 cells. Results and Conclusion. Eight main active components, 64 potential antidepressant gene targets, and 15 core antidepressant gene targets were obtained. 35 signaling pathways and 52 biological processes related to antidepressant effect of Puerariae Radix were identified. Puerarin was the active ingredient derived from Puerariae Radix which exhibited the antidepression effect by improving the viability of cell, reducing cell apoptosis, regulating ROS production, increasing protein expressions of AKT1 and FOS, and reducing protein expressions of CASP3, STAT3, and TNF-α. The study revealed the pharmacodynamic material basis and possible antidepressant mechanism of Puerariae Radix and provided new theoretical basis and ideas for antidepressant research.
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Affiliation(s)
- Guoze Wang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, China
| | - Peng Luo
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, China
| | - Shuai Zhang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China
- Department of Interventional Radiology, The Affiliated Cancer Hospital of Guizhou Medical University, Guiyang 550000, China
| | - Qun Huang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, China
| | - Shuling Zhang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, China
| | - Qibing Zeng
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China
| | - Jingxin Mao
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, China
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Pan Y, He X, Li C, Li Y, Li W, Zhang H, Wang Y, Zhou G, Yang J, Li J, Qu J, Wang H, Gao Z, Shen Y, Li T, Hu H, Ma H. Neuronal activity recruits the CRTC1/CREB axis to drive transcription-dependent autophagy for maintaining late-phase LTD. Cell Rep 2021; 36:109398. [PMID: 34289350 DOI: 10.1016/j.celrep.2021.109398] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 05/05/2021] [Accepted: 06/22/2021] [Indexed: 12/31/2022] Open
Abstract
Cellular resources must be reorganized for long-term synaptic plasticity during brain information processing, in which coordinated gene transcription and protein turnover are required. However, the mechanism underlying this process remains elusive. Here, we report that activating N-methyl-d-aspartate receptors (NMDARs) induce transcription-dependent autophagy for synaptic turnover and late-phase long-term synaptic depression (L-LTD), which invokes cytoplasm-to-nucleus signaling mechanisms known to be required for late-phase long-term synaptic potentiation (L-LTP). Mechanistically, LTD-inducing stimuli specifically dephosphorylate CRTC1 (CREB-regulated transcription coactivator 1) at Ser-151 and are advantaged in recruiting CRTC1 from cytoplasm to the nucleus, where it competes with FXR (fed-state sensing nuclear receptor) for binding to CREB (cAMP response element-binding protein) and drives autophagy gene expression. Disrupting synergistic actions of CREB and CRTC1 (two essential L-LTP transcription factors) impairs transcription-dependent autophagy induction and prevents NMDAR-dependent L-LTD, which can be rescued by constitutively inducing mechanistic target of rapamycin (mTOR)-dependent autophagy. Together, these findings uncover mechanistic commonalities between L-LTP and L-LTD, suggesting that synaptic activity can tune excitation-transcription coupling for distinct long-lasting synaptic remodeling.
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Affiliation(s)
- Yue Pan
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Xingzhi He
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Cuicui Li
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Yanjun Li
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Wenwen Li
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Hanbin Zhang
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Yang Wang
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Guangjun Zhou
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Jing Yang
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Jiarui Li
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Jing Qu
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Hao Wang
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Zhihua Gao
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Ying Shen
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Tao Li
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China
| | - Hailan Hu
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China; Research Units for Emotion and Emotion Disorders, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Huan Ma
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Affiliated Mental Health Center, Zhejiang University School of Medicine, Hangzhou 310058, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou 310058, China; Research Units for Emotion and Emotion Disorders, Chinese Academy of Medical Sciences, Beijing 100730, China.
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9
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Hoang TH, Böge J, Manahan-Vaughan D. Hippocampal subfield-specific Homer1a expression is triggered by learning-facilitated long-term potentiation and long-term depression at medial perforant path synapses. Hippocampus 2021; 31:897-915. [PMID: 33964041 DOI: 10.1002/hipo.23333] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 03/22/2021] [Accepted: 04/11/2021] [Indexed: 12/23/2022]
Abstract
Learning about general aspects, or content details, of space results in differentiated neuronal information encoding within the proximodistal axis of the hippocampus. These processes are tightly linked to long-term potentiation (LTP) and long-term depression (LTD). Here, we explored the precise sites of encoding of synaptic plasticity in the hippocampus that are mediated by information throughput from the perforant path. We assessed nuclear Homer1a-expression that was triggered by electrophysiological induction of short and long forms of hippocampal synaptic plasticity, and compared it to Homer1a-expression that was triggered by LTP and LTD enabled by different forms of spatial learning. Plasticity responses were induced by patterned stimulation of the perforant path and were recorded in the dentate gyrus (DG) of freely behaving rats. We used fluorescence in situ hybridization to detect experience-dependent nuclear encoding of Homer1a in proximodistal hippocampal subfields. Induction of neither STP nor STD resulted in immediate early gene (IEG) encoding. Electrophysiological induction of robust LTP, or LTD, resulted in highly significant and widespread induction of nuclear Homer1a in all hippocampal subfields. LTP that was facilitated by novel spatial exploration triggered similar widespread Homer1a-expression. The coupling of synaptic depression with the exploration of a novel configuration of landmarks resulted in localized IEG expression in the proximal CA3 region and the lower (infrapyramidal) blade of the DG. Our findings support that synaptic plasticity induction via perforant path inputs promotes widespread hippocampal information encoding. Furthermore, novel spatial exploration promotes the selection of a hippocampal neuronal network by means of LTP that is distributed in an experience-dependent manner across all hippocampus subfields. This network may be modified during spatial content learning by LTD in specific hippocampal subfields. Thus, long-term plasticity-inducing events result in IEG expression that supports establishment and/or restructuring of neuronal networks that are necessary for long-term information storage.
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Affiliation(s)
- Thu-Huong Hoang
- Medical Faculty, Department of Neurophysiology, Ruhr University Bochum, Bochum, Germany.,International Graduate School of Neuroscience, Ruhr University Bochum, Bochum, Germany
| | - Juliane Böge
- Medical Faculty, Department of Neurophysiology, Ruhr University Bochum, Bochum, Germany
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10
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Méndez-Couz M, Krenzek B, Manahan-Vaughan D. Genetic Depletion of BDNF Impairs Extinction Learning of a Spatial Appetitive Task in the Presence or Absence of the Acquisition Context. Front Behav Neurosci 2021; 15:658686. [PMID: 33994970 PMCID: PMC8119774 DOI: 10.3389/fnbeh.2021.658686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 03/26/2021] [Indexed: 12/12/2022] Open
Abstract
Brain derived neurotropic factor (BDNF) supports neuronal survival, growth, and differentiation and is involved in forms of hippocampus-dependent and independent learning, as well as hippocampus-dependent learning. Extinction learning comprises active inhibition of no-longer relevant learned information, in conjunction with a decreased response of a previously learned behavior. It is highly dependent on context, and evidence exists that it requires hippocampal activation. The participation of BDNF in memory processing is experience-dependent. For example, BDNF has been associated with synaptic plasticity needed for spatial learning, and it is involved in acquisition and extinction learning of fear conditioning. However, little is known about its role in spatial appetitive extinction learning. In this study, we evaluated to what extent BDNF contributes to spatial appetitive extinction learning in the presence (ABA) or absence (AAA) of exposure to the acquisition context. Daily training, of BDNF+/--mice or their wildtype (WT) littermates, to reach acquisition criterion in a T-maze, resulted in a similar performance outcome. However, extinction learning was delayed in the AAA, and impaired in the ABA-paradigm compared to performance in WT littermates. Trial-by-trial learning analysis indicated differences in the integration of the context into extinction learning by BDNF+/--mice compared to WT littermates. Taken together, these results support an important role for BDNF in processes that relate to information updating and retrieval that in turn are crucial for effective extinction learning.
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Affiliation(s)
- Marta Méndez-Couz
- Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Bochum, Germany
| | - Beate Krenzek
- Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Bochum, Germany
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11
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Wang F, Xie N, Zhou J, Dai M, Zhang Q, Hardiman PJ, Qu F. Molecular mechanisms underlying altered neurobehavioural development of female offspring of mothers with polycystic ovary syndrome: FOS-mediated regulation of neurotrophins in placenta. EBioMedicine 2020; 60:102993. [PMID: 32949999 PMCID: PMC7501055 DOI: 10.1016/j.ebiom.2020.102993] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/31/2020] [Accepted: 08/24/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND This study explored the mechanisms underlying altered neurobehavioural development of female offspring born to mothers with polycystic ovary syndrome (PCOS). METHODS In total, 20 women with PCOS and 32 healthy women who underwent caesarean deliveries with a single female foetus were recruited. Infants were assessed with Dubowitz scoring. Swan71 cell line with stable FOS overexpression was used to verify the regulatory effects of FOS on brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) expression. Learning and memory in female first-generation (F1) and second-generation (F2) offspring in a rat model of PCOS was tested using the Morris water maze at puberty and adulthood. Transcriptome analysis of pubertal hippocampi and hypothalami of female F1 offspring was conducted. FINDINGS Total score and behaviour subscales of Dubowitz scoring were significantly lower in female infants of women with PCOS. FOS and NGF protein levels were downregulated in placental villi of the PCOS group. FOS played a key role in BDNF inhibition and enhancing NGF in Swan71 cells. PCOS female F1 rats exhibited lower target crossing times during puberty when compared to controls. Transcriptome analysis revealed significant changes in hippocampal and hypothalamic neuronal pathways in female F1 rats at puberty. INTERPRETATION FOS regulation of neurotrophins in the placenta negatively affects neurobehavioural development of female offspring of PCOS mothers. FUNDING This study was funded by the National Key R&D Program of China (2018YFC1004900 to F.Q. and F.W.) and the National Natural Science Foundation of China (81874480 to F.Q.; 81873837 to F.W.).
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Affiliation(s)
- Fangfang Wang
- Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China
| | - Ningning Xie
- Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China
| | - Jue Zhou
- College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Minchen Dai
- Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China
| | - Qing Zhang
- Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China
| | - Paul J Hardiman
- Institute for Women's Health, University College London, London NW3 2PF, United Kingdom
| | - Fan Qu
- Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China; Institute for Women's Health, University College London, London NW3 2PF, United Kingdom.
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12
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Grijalva LE, Miranda MI, Paredes RG. Differential changes in GAP-43 or synaptophysin during appetitive and aversive taste memory formation. Behav Brain Res 2020; 397:112937. [PMID: 32991926 DOI: 10.1016/j.bbr.2020.112937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 09/19/2020] [Accepted: 09/21/2020] [Indexed: 10/23/2022]
Abstract
Association between events in time and space is a major mechanism for all animals, including humans, which allows them to learn about the world and potentially change their behavior in the future to adapt to different environments. Conditioning taste aversion (CTA) is a single-trial learning paradigm where animals are trained to avoid a novel flavor which is associated with malaise. Many variables can be analyzed with this model and the circuits involved are well described. Thus, the amygdala and the gustatory cortex (GC) are some of the most relevant structures involved in CTA. In the present study we focused in plastic changes that occur during appetitive and/or aversive taste memory formation. Previous studies have demonstrated that memory consolidation, in hippocampal dependent paradigms, induces plastic changes like increase in the concentration of proteins considered as markers of neuronal plasticity, such as the growth associated protein 43 (GAP-43) and synaptophysin (SYN). In the present experiment in male rats we evaluated changes in GAP-43 and SYN expression, using immunofluorescence, induce by the formation of aversive and appetitive taste memory. We found that taste aversive memory formation can induce an increase in GAP-43 in the granular layer of the GC. Furthermore, we also found an increase in SYN expression in both layers of the GC, the basolateral amygdala (BLA) and the central amygdala (CeA). These results suggest that aversive memory representation induces a new circuitry (inferred from an increase in GAP 43). On the other hand, an appetitive taste learning increased SYN expression in the GC (both layers), the BLA and the CeA without any changes in GAP 43. Together these results indicate that aversive memory formation induces structural and synaptic changes, while appetitive memory formation induces synaptic changes; suggesting that aversive and appetitive memories require a different set of cortical and amygdala plastic changes.
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Affiliation(s)
- Lucia E Grijalva
- Instituto de Neurobiología, UNAM, Campus Juriquilla, Querétaro, 76230, Mexico
| | - María I Miranda
- Instituto de Neurobiología, UNAM, Campus Juriquilla, Querétaro, 76230, Mexico
| | - Raúl G Paredes
- Instituto de Neurobiología, UNAM, Campus Juriquilla, Querétaro, 76230, Mexico; Escuela Nacional de Estudios Superiores, Unidad Juriquilla, UNAM, Querétaro, 76230 Mexico.
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13
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Simbriger K, Amorim IS, Lach G, Chalkiadaki K, Kouloulia S, Jafarnejad SM, Khoutorsky A, Gkogkas CG. Uncovering memory-related gene expression in contextual fear conditioning using ribosome profiling. Prog Neurobiol 2020; 197:101903. [PMID: 32860876 PMCID: PMC7859833 DOI: 10.1016/j.pneurobio.2020.101903] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 06/30/2020] [Accepted: 08/23/2020] [Indexed: 11/14/2022]
Abstract
Contextual fear conditioning (CFC) in rodents is the most widely used behavioural paradigm in neuroscience research to elucidate the neurobiological mechanisms underlying learning and memory. It is based on the pairing of an aversive unconditioned stimulus (US; e.g. mild footshock) with a neutral conditioned stimulus (CS; e.g. context of the test chamber) in order to acquire associative long-term memory (LTM), which persists for days and even months. Using genome-wide analysis, several studies have generated lists of genes modulated in response to CFC in an attempt to identify the “memory genes”, which orchestrate memory formation. Yet, most studies use naïve animals as a baseline for assessing gene-expression changes, while only few studies have examined the effect of the US alone, without pairing to context, using genome-wide analysis of gene-expression. Herein, using the ribosome profiling methodology, we show that in male mice an immediate shock, which does not lead to LTM formation, elicits pervasive translational and transcriptional changes in the expression of Immediate Early Genes (IEGs) in dorsal hippocampus (such as Fos and Arc), a fact which has been disregarded by the majority of CFC studies. By removing the effect of the immediate shock, we identify and validate a new set of genes, which are translationally and transcriptionally responsive to the association of context-to-footshock in CFC, and thus constitute salient “memory genes”.
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Affiliation(s)
- Konstanze Simbriger
- Centre for Discovery Brain Sciences, University of Edinburgh and Patrick Wild Centre and Simons Initiative for the Developing Brain, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Inês S Amorim
- Centre for Discovery Brain Sciences, University of Edinburgh and Patrick Wild Centre and Simons Initiative for the Developing Brain, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Gilliard Lach
- Centre for Discovery Brain Sciences, University of Edinburgh and Patrick Wild Centre and Simons Initiative for the Developing Brain, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Kleanthi Chalkiadaki
- Centre for Discovery Brain Sciences, University of Edinburgh and Patrick Wild Centre and Simons Initiative for the Developing Brain, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Stella Kouloulia
- Centre for Discovery Brain Sciences, University of Edinburgh and Patrick Wild Centre and Simons Initiative for the Developing Brain, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Seyed Mehdi Jafarnejad
- Patrick G. Johnston Centre for Cancer Research and Cell Biology, The Queen's University of Belfast, BT9 7AE Belfast, Northern Ireland, UK.
| | - Arkady Khoutorsky
- Department of Anesthesia, Faculty of Dentistry and Alan Edwards Centre for Research on Pain, McGill University, H3A 0G1, Montréal, QC, Canada.
| | - Christos G Gkogkas
- Centre for Discovery Brain Sciences, University of Edinburgh and Patrick Wild Centre and Simons Initiative for the Developing Brain, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK.
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14
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Distinct Genetic Signatures of Cortical and Subcortical Regions Associated with Human Memory. eNeuro 2019; 6:ENEURO.0283-19.2019. [PMID: 31818829 PMCID: PMC6917897 DOI: 10.1523/eneuro.0283-19.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 11/12/2019] [Accepted: 11/19/2019] [Indexed: 11/21/2022] Open
Abstract
Despite the discovery of gene variants linked to memory performance, understanding the genetic basis of adult human memory remains a challenge. Here, we devised an unsupervised framework that relies on spatial correlations between human transcriptome data and functional neuroimaging maps to uncover the genetic signatures of memory in functionally-defined cortical and subcortical memory regions. Despite the discovery of gene variants linked to memory performance, understanding the genetic basis of adult human memory remains a challenge. Here, we devised an unsupervised framework that relies on spatial correlations between human transcriptome data and functional neuroimaging maps to uncover the genetic signatures of memory in functionally-defined cortical and subcortical memory regions. Results were validated with animal literature and showed that our framework is highly effective in identifying memory-related processes and genes compared to a control cognitive function. Genes preferentially expressed in cortical memory regions are linked to memory-related processes such as immune and epigenetic regulation. Genes expressed in subcortical memory regions are associated with neurogenesis and glial cell differentiation. Genes expressed in both cortical and subcortical memory areas are involved in the regulation of transcription, synaptic plasticity, and glutamate receptor signaling. Furthermore, distinct memory-associated genes such as PRKCD and CDK5 are linked to cortical and subcortical regions, respectively. Thus, cortical and subcortical memory regions exhibit distinct genetic signatures that potentially reflect functional differences in health and disease, and nominates gene candidates for future experimental investigations.
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15
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Zheng H, Ton H, Yang L, Liufu N, Dong Y, Zhang Y, Xie Z. Acute Fasting Does Not Induce Cognitive Impairment in Mice. Front Neurosci 2019; 13:896. [PMID: 31507368 PMCID: PMC6718131 DOI: 10.3389/fnins.2019.00896] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 08/09/2019] [Indexed: 12/17/2022] Open
Abstract
Preoperative baseline cognitive impairment is associated with postoperative neurocognitive disorder (PND). Fasting, and more generally, calorie restriction has been shown to exert controversial effects in clinical settings and various animal models of neurological disorders. Every patient needs acute fasting before anesthesia and surgery. However, the impact of acute fasting on cognitive function remain largely unknown. We, therefore, set out to determine whether acute fasting can induce neurotoxicity and neurobehavioral deficits in rodents. In the present system establishment study, a mouse model of acute fasting was established. The effects of the acute fasting on natural and learned behavior were evaluated in the buried food test, open field test and the Y maze test. The expression of c-Fos, the marker of neuronal activation, and caspase-3 activation, the marker of cellular apoptosis, were measured with immunohistochemistry. We found that the 9 h acute fasting increased the latency to eat food in the buried food test. The acute fasting also selectively increased the total distance and decreased the freezing time in open field test, and increased the duration in the novel arm in the Y maze test. Besides, the immunohistochemical study showed that the fasting significantly increased the c-Fos level in the hippocampus and various sub-cortical areas, including paraventricular thalamus (PVT), dorsomedial hypothalamus (DMH), lateral hypothalamus (LH), and basal amygdala (BMA). However, the acute fasting did not induce apoptosis, demonstrating by no appearance of caspase-3 activation in the corresponding brain areas. These data showed that acute fasting did not cause cellular apoptosis and cognitive impairment in the mice. Instead, the acute fasting increased the neuronal activity, enhanced the ambulatory activity and improved the spatial recognition memory in the mice. These findings will promote more research in the established system to further determine the effects of perioperative factors on the postoperative neurocognitive function and the underlying mechanisms.
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Affiliation(s)
- Hua Zheng
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Hoai Ton
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Lei Yang
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States.,Department of Anesthesiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Ning Liufu
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States.,Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Yuanlin Dong
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Yiying Zhang
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Zhongcong Xie
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
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16
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Sun Q, Zeng Q, Chen Y, Zhang M, Wei L, Chen P. Long intergenic noncoding RNA p21 suppresses the apoptosis of hippocampus neurons in streptozotocin‐diabetic mice by sponging microRNA‐221 through upregulation of FOS. J Cell Physiol 2019; 234:21113-21125. [PMID: 31081202 DOI: 10.1002/jcp.28714] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 01/03/2023]
Affiliation(s)
- Qin Sun
- Department of Geriatrics Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital Chengdu China
| | - Qing‐Cui Zeng
- Department of Geriatrics Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital Chengdu China
| | - Yan‐Qiu Chen
- Department of Neurology People's Hospital of Chongqing Yubei District Chongqing China
| | - Min Zhang
- Department of Geriatrics Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital Chengdu China
| | - Ling‐Ling Wei
- Center of Diabetes Mellitus Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital Chengdu China
- School of Medicine, University of Electronic Science and Technology of China Chengdu China
| | - Ping Chen
- Department of Geriatrics Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital Chengdu China
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17
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Jakob TF, Illing RB, Rosskothen-Kuhl N. Monaural Neonatal Deafness Induces Inhibition among Bilateral Auditory Networks under Binaural Activation. Neuroscience 2019; 400:1-16. [DOI: 10.1016/j.neuroscience.2018.12.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 12/18/2018] [Accepted: 12/19/2018] [Indexed: 11/15/2022]
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18
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Robakiewicz I, Polak M, Rawska M, Alberski D, Polowy R, Wytrychiewicz K, Syperek M, Matysiak J, Filipkowski RK. Stimulus-seeking in rats is accompanied by increased c-Fos expression in hippocampal CA1 as well as short 22 kHz and flat 50 kHz calls. Acta Neurobiol Exp (Wars) 2019. [DOI: 10.21307/ane-2019-029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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19
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Inhibition of microRNA-124-3p as a novel therapeutic strategy for the treatment of Gulf War Illness: Evaluation in a rat model. Neurotoxicology 2018; 71:16-30. [PMID: 30503814 DOI: 10.1016/j.neuro.2018.11.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 11/01/2018] [Accepted: 11/20/2018] [Indexed: 12/27/2022]
Abstract
Gulf War Illness (GWI) is a chronic, multisymptom illness that continues to affect up to 30% of veterans deployed to the Persian Gulf during the 1990-1991 Gulf War. After nearly 30 years, useful treatments for GWI are lacking and underlying cellular and molecular mechanisms involved in its pathobiology remain poorly understood, although exposures to pyridostigmine bromide (PB) and pesticides are consistently identified to be among the strongest risk factors. Alleviation of the broad range of symptoms manifested in GWI, which involve the central nervous system, the neuroendocrine system, and the immune system likely requires therapies that are able to activate and inactivate a large set of orchestrated genes. Previous work in our laboratory using an established rat model of GWI identified persistent elevation of microRNA-124-3p (miR-124) levels in the hippocampus whose numerous gene targets are involved in cognition-associated pathways and neuroendocrine function. This study aimed to investigate the broad effects of miR-124 inhibition in the brain 9 months after completion of a 28-day exposure regimen of PB, DEET (N,N-diethyl-3-methylbenzamide), permethrin, and mild stress by profiling the hippocampal expression of genes known to play a critical role in synaptic plasticity, glucocorticoid signaling, and neurogenesis. We determined that intracerebroventricular infusion of a miR-124 antisense oligonucleotide (miR-124 inhibitor; 0.05-0.5 nmol/day/28 days), but not a negative control oligonucleotide, into the lateral ventricle of the brain caused increased protein expression of multiple validated miR-124 targets and increased expression of downstream target genes important for cognition and neuroendocrine signaling in the hippocampus. Off-target cardiotoxic effects were revealed in GWI rats receiving 0.1 nmol/day as indicated by the detection in plasma of 5 highly elevated protein cardiac injury markers and 6 upregulated cardiac-enriched miRNAs in plasma exosomes determined by next-generation sequencing. Results from this study suggest that in vivo inhibition of miR-124 function in the hippocampus is a promising, novel therapeutic approach to improve cognition and neuroendocrine dysfunction in GWI. Additional preclinical studies in animal models to assess feasibility and safety by developing a practical, noninvasive drug delivery system to the brain and exploring potential adverse toxicologic effects of miR-124 inhibition are warranted.
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20
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Chaaya N, Battle AR, Johnson LR. An update on contextual fear memory mechanisms: Transition between Amygdala and Hippocampus. Neurosci Biobehav Rev 2018; 92:43-54. [DOI: 10.1016/j.neubiorev.2018.05.013] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 03/02/2018] [Accepted: 05/08/2018] [Indexed: 12/27/2022]
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21
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Gallo FT, Katche C, Morici JF, Medina JH, Weisstaub NV. Immediate Early Genes, Memory and Psychiatric Disorders: Focus on c-Fos, Egr1 and Arc. Front Behav Neurosci 2018; 12:79. [PMID: 29755331 PMCID: PMC5932360 DOI: 10.3389/fnbeh.2018.00079] [Citation(s) in RCA: 214] [Impact Index Per Article: 35.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 04/10/2018] [Indexed: 01/08/2023] Open
Abstract
Many psychiatric disorders, despite their specific characteristics, share deficits in the cognitive domain including executive functions, emotional control and memory. However, memory deficits have been in many cases undervalued compared with other characteristics. The expression of Immediate Early Genes (IEGs) such as, c-fos, Egr1 and arc are selectively and promptly upregulated in learning and memory among neuronal subpopulations in regions associated with these processes. Changes in expression in these genes have been observed in recognition, working and fear related memories across the brain. Despite the enormous amount of data supporting changes in their expression during learning and memory and the importance of those cognitive processes in psychiatric conditions, there are very few studies analyzing the direct implication of the IEGs in mental illnesses. In this review, we discuss the role of some of the most relevant IEGs in relation with memory processes affected in psychiatric conditions.
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Affiliation(s)
- Francisco T Gallo
- Instituto de Fisiología y Biofísica Bernardo Houssay, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
| | - Cynthia Katche
- Instituto de Biología Celular y Neurociencias (IBCN) Dr. Eduardo de Robertis, Facultad de Medicina, CONICET, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
| | - Juan F Morici
- Instituto de Fisiología y Biofísica Bernardo Houssay, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
| | - Jorge H Medina
- Instituto de Biología Celular y Neurociencias (IBCN) Dr. Eduardo de Robertis, Facultad de Medicina, CONICET, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina.,Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos (UBA), Buenos Aires, Argentina
| | - Noelia V Weisstaub
- Instituto de Fisiología y Biofísica Bernardo Houssay, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
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22
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Katche C, Medina JH. Requirement of an Early Activation of BDNF/c-Fos Cascade in the Retrosplenial Cortex for the Persistence of a Long-Lasting Aversive Memory. Cereb Cortex 2018; 27:1060-1067. [PMID: 26646512 DOI: 10.1093/cercor/bhv284] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
During the past few years, there has been growing interest in the role of the retrosplenial cortex (RSC) in memory processing. However, little is known about the molecular changes that take place in this brain region during memory formation. In the present work, we studied the early post-training participation of RSC in the formation of a long-lasting memory in rats. We found an increase in c-Fos levels in the anterior part of the RSC (aRSC) after inhibitory avoidance (IA) training. Interestingly, this increase was associated with memory durability, since blocking c-Fos expression using specific antisense oligonucleotides (ASO) impaired long-lasting retention 7 days after training without affecting memory expression 2 days after training. In addition, we showed that BDNF is one of the upstream signals for c-Fos expression required for memory persistence, since blocking BDNF synthesis prevents IA training-induced increase in c-Fos levels in aRSC and affects memory persistence. In addition, we found that injection of BDNF into aRSC around training was sufficient to establish a persistent memory and that this effect was prevented by c-fos ASO infusion into the same structure. These findings reveal an early post-training involvement of aRSC in the processing of a long-lasting aversive memory.
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Affiliation(s)
- Cynthia Katche
- Laboratorio de Memoria, IBCN, Facultad de Medicina, Universidad de Buenos, Ciudad Autónoma de Buenos AiresC1121ABG, Argentina
| | - Jorge H Medina
- Laboratorio de Memoria, IBCN, Facultad de Medicina, Universidad de Buenos, Ciudad Autónoma de Buenos Aires C1121ABG, Argentina.,Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos, Ciudad Autónoma de Buenos Aires C1121ABG, Argentina
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Eagle AL, Gajewski PA, Robison AJ. Role of hippocampal activity-induced transcription in memory consolidation. Rev Neurosci 2018; 27:559-73. [PMID: 27180338 DOI: 10.1515/revneuro-2016-0010] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 03/26/2016] [Indexed: 01/15/2023]
Abstract
Experience-dependent changes in the strength of connections between neurons in the hippocampus (HPC) are critical for normal learning and memory consolidation, and disruption of this process drives a variety of neurological and psychiatric diseases. Proper HPC function relies upon discrete changes in gene expression driven by transcription factors (TFs) induced by neuronal activity. Here, we describe the induction and function of many of the most well-studied HPC TFs, including cyclic-AMP response element binding protein, serum-response factor, AP-1, and others, and describe their role in the learning process. We also discuss the known target genes of many of these TFs and the purported mechanisms by which they regulate long-term changes in HPC synaptic strength. Moreover, we propose that future research in this field will depend upon unbiased identification of additional gene targets for these activity-dependent TFs and subsequent meta-analyses that identify common genes or pathways regulated by multiple TFs in the HPC during learning or disease.
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Item-Place Encoding Through Hippocampal Long-Term Depression. HANDBOOK OF OBJECT NOVELTY RECOGNITION 2018. [DOI: 10.1016/b978-0-12-812012-5.00019-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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25
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McGregor G, Irving AJ, Harvey J. Canonical JAK‐STAT signaling is pivotal for long‐term depression at adult hippocampal temporoammonic‐CA1 synapses. FASEB J 2017; 31:3449-3466. [DOI: 10.1096/fj.201601293rr] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 04/11/2017] [Indexed: 12/30/2022]
Affiliation(s)
- Gemma McGregor
- Division of NeuroscienceSchool of MedicineNinewells Hospital and Medical SchoolUniversity of Dundee Dundee United Kingdom
| | - Andrew J. Irving
- School of Biomolecular and Biomedical ScienceThe Conway InstituteUniversity College Dublin Dublin Ireland
| | - Jenni Harvey
- Division of NeuroscienceSchool of MedicineNinewells Hospital and Medical SchoolUniversity of Dundee Dundee United Kingdom
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Ballesteros JJ, Buschler A, Köhr G, Manahan-Vaughan D. Afferent Input Selects NMDA Receptor Subtype to Determine the Persistency of Hippocampal LTP in Freely Behaving Mice. Front Synaptic Neurosci 2016; 8:33. [PMID: 27818632 PMCID: PMC5073893 DOI: 10.3389/fnsyn.2016.00033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 09/26/2016] [Indexed: 01/07/2023] Open
Abstract
The glutamatergic N-methyl-D-aspartate receptor (NMDAR) is critically involved in many forms of hippocampus-dependent memory that may be enabled by synaptic plasticity. Behavioral studies with NMDAR antagonists and NMDAR subunit (GluN2) mutants revealed distinct contributions from GluN2A- and GluN2B-containing NMDARs to rapidly and slowly acquired memory performance. Furthermore, studies of synaptic plasticity, in genetically modified mice in vitro, suggest that GluN2A and GluN2B may contribute in different ways to the induction and longevity of synaptic plasticity. In contrast to the hippocampal slice preparation, in behaving mice, the afferent frequencies that induce synaptic plasticity are very restricted and specific. In fact, it is the stimulus pattern and not variations in afferent frequency that determine the longevity of long-term potentiation (LTP) in vivo. Here, we explored the contribution of GluN2A and GluN2B to LTP of differing magnitudes and persistence in freely behaving mice. We applied differing high-frequency stimulation (HFS) patterns at 100 Hz to the hippocampal CA1 region, to induce NMDAR-dependent LTP in wild-type (WT) mice, that endured for <1 h (early (E)-LTP), (LTP, 2–4 h) or >24 h (late (L)-LTP). In GluN2A-knockout (KO) mice, E-LTP (HFS, 50 pulses) was significantly reduced in magnitude and duration, whereas LTP (HFS, 2 × 50 pulses) and L-LTP (HFS, 4 × 50 pulses) were unaffected compared to responses in WT animals. By contrast, pharmacological antagonism of GluN2B in WT had no effect on E-LTP but significantly prevented LTP. E-LTP and LTP were significantly impaired by GluN2B antagonism in GluN2A-KO mice. These data indicate that the pattern of afferent stimulation is decisive for the recruitment of distinct GluN2A and GluN2B signaling pathways that in turn determine the persistency of hippocampal LTP. Whereas brief bursts of patterned stimulation preferentially recruit GluN2A and lead to weak and short-lived forms of LTP, prolonged, more intense, afferent activation recruits GluN2B and leads to robust and persistent LTP. These unique signal-response properties of GluN2A and GluN2B enable qualitative differentiation of information encoding in hippocampal synapses.
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Affiliation(s)
- Jesús J Ballesteros
- Department of Neurophysiology, Medical Faculty, Ruhr University Bochum Bochum, Germany
| | - Arne Buschler
- Department of Neurophysiology, Medical Faculty, Ruhr University Bochum Bochum, Germany
| | - Georg Köhr
- Max Planck Institute for Medical Research Heidelberg, Germany
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27
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Correia SS, McGrath AG, Lee A, Graybiel AM, Goosens KA. Amygdala-ventral striatum circuit activation decreases long-term fear. eLife 2016; 5:e12669. [PMID: 27671733 PMCID: PMC5039029 DOI: 10.7554/elife.12669] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 08/14/2016] [Indexed: 12/18/2022] Open
Abstract
In humans, activation of the ventral striatum, a region associated with reward processing, is associated with the extinction of fear, a goal in the treatment of fear-related disorders. This evidence suggests that extinction of aversive memories engages reward-related circuits, but a causal relationship between activity in a reward circuit and fear extinction has not been demonstrated. Here, we identify a basolateral amygdala (BLA)-ventral striatum (NAc) pathway that is activated by extinction training. Enhanced recruitment of this circuit during extinction learning, either by pairing reward with fear extinction training or by optogenetic stimulation of this circuit during fear extinction, reduces the return of fear that normally follows extinction training. Our findings thus identify a specific BLA-NAc reward circuit that can regulate the persistence of fear extinction and point toward a potential therapeutic target for disorders in which the return of fear following extinction therapy is an obstacle to treatment.
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Affiliation(s)
- Susana S Correia
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
| | - Anna G McGrath
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
| | - Allison Lee
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
| | - Ann M Graybiel
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
| | - Ki A Goosens
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
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28
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Crespo-García M, Zeiller M, Leupold C, Kreiselmeyer G, Rampp S, Hamer HM, Dalal SS. Slow-theta power decreases during item-place encoding predict spatial accuracy of subsequent context recall. Neuroimage 2016; 142:533-543. [PMID: 27521743 DOI: 10.1016/j.neuroimage.2016.08.021] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 07/26/2016] [Accepted: 08/09/2016] [Indexed: 12/31/2022] Open
Abstract
Human hippocampal theta oscillations play a key role in accurate spatial coding. Associative encoding involves similar hippocampal networks but, paradoxically, is also characterized by theta power decreases. Here, we investigated how theta activity relates to associative encoding of place contexts resulting in accurate navigation. Using MEG, we found that slow-theta (2-5Hz) power negatively correlated with subsequent spatial accuracy for virtual contextual locations in posterior hippocampus and other cortical structures involved in spatial cognition. A rare opportunity to simultaneously record MEG and intracranial EEG in an epilepsy patient provided crucial insights: during power decreases, slow-theta in right anterior hippocampus and left inferior frontal gyrus phase-led the left temporal cortex and predicted spatial accuracy. Our findings indicate that decreased slow-theta activity reflects local and long-range neural mechanisms that encode accurate spatial contexts, and strengthens the view that local suppression of low-frequency activity is essential for more efficient processing of detailed information.
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Affiliation(s)
- Maité Crespo-García
- Department of Psychology, University of Konstanz, 78464 Konstanz, Germany; Zukunftskolleg, University of Konstanz, 78464 Konstanz, Germany.
| | - Monika Zeiller
- Department of Psychology, University of Konstanz, 78464 Konstanz, Germany
| | - Claudia Leupold
- Department of Neurosurgery, Epilepsy Center, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Gernot Kreiselmeyer
- Department of Neurology, Epilepsy Center, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Stefan Rampp
- Department of Neurosurgery, Epilepsy Center, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Hajo M Hamer
- Department of Neurology, Epilepsy Center, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Sarang S Dalal
- Department of Psychology, University of Konstanz, 78464 Konstanz, Germany; Zukunftskolleg, University of Konstanz, 78464 Konstanz, Germany
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29
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Abstract
Resolving how our brains encode information requires an understanding of the cellular processes taking place during memory formation. Since the 1970s, considerable effort has focused on determining the properties and mechanisms underlying long-term potentiation (LTP) at glutamatergic synapses and how these processes influence initiation of new memories. However, accumulating evidence suggests that long-term depression (LTD) of synaptic strength, particularly at glutamatergic synapses, is a bona fide learning and memory mechanism in the mammalian brain. The known range of mechanisms capable of inducing LTD has been extended to those including NMDAR-independent forms, neuromodulator-dependent LTD, synaptic depression following stress, and non-synaptically induced forms. The examples of LTD observed at the hippocampal CA1 synapse to date demonstrate features consistent with LTP, including homo- and heterosynaptic expression, extended duration beyond induction (several hours to weeks), and association with encoding of distinct types of memories. Canonical mechanisms through which synapses undergo LTD include activation of phosphatases, initiation of protein synthesis, and dynamic regulation of presynaptic glutamate release and/or postsynaptic glutamate receptor endocytosis. Here, we will discuss the pre- and postsynaptic changes underlying LTD, recent advances in the identification and characterization of novel mechanisms underlying LTD, and how engagement of these processes constitutes a cellular analog for the genesis of specific types of memories.
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Affiliation(s)
- Steven A Connor
- Brain Research Centre and Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Yu Tian Wang
- Brain Research Centre and Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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30
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Jakob TF, Döring U, Illing RB. The pattern of Fos expression in the rat auditory brainstem changes with the temporal structure of binaural electrical intracochlear stimulation. Exp Neurol 2015; 266:55-67. [DOI: 10.1016/j.expneurol.2015.02.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 01/20/2015] [Accepted: 02/10/2015] [Indexed: 12/24/2022]
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31
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In search of a recognition memory engram. Neurosci Biobehav Rev 2014; 50:12-28. [PMID: 25280908 PMCID: PMC4382520 DOI: 10.1016/j.neubiorev.2014.09.016] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2014] [Revised: 09/18/2014] [Accepted: 09/22/2014] [Indexed: 01/06/2023]
Abstract
The role of the perirhinal cortex in familiarity discrimination is reviewed. Behavioural, pharmacological and electrophysiological evidence is considered. The cortex is found to be essential for memory acquisition, retrieval and storage. The evidence indicates that perirhinal synaptic weakening is critically involved.
A large body of data from human and animal studies using psychological, recording, imaging, and lesion techniques indicates that recognition memory involves at least two separable processes: familiarity discrimination and recollection. Familiarity discrimination for individual visual stimuli seems to be effected by a system centred on the perirhinal cortex of the temporal lobe. The fundamental change that encodes prior occurrence within the perirhinal cortex is a reduction in the responses of neurones when a stimulus is repeated. Neuronal network modelling indicates that a system based on such a change in responsiveness is potentially highly efficient in information theoretic terms. A review is given of findings indicating that perirhinal cortex acts as a storage site for recognition memory of objects and that such storage depends upon processes producing synaptic weakening.
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32
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Molecular neuroimaging of post-injury plasticity. J Mol Neurosci 2014; 54:630-8. [PMID: 24909382 DOI: 10.1007/s12031-014-0347-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 05/29/2014] [Indexed: 12/28/2022]
Abstract
Nerve injury induces long-term changes in neuronal activity in the primary somatosensory cortex (S1), which has often been implicated as the origin of sensory dysfunction. However, the cellular mechanisms underlying this phenomenon remain unclear. C-fos is an immediate early gene, which has been shown to play an instrumental role in plasticity. By developing a new platform to image real-time changes in gene expression in vivo, we investigated whether injury modulates the levels of c-fos in layer V of S1, since previous studies have suggested that these neurons are particularly susceptible to injury. The yellow fluorescent protein, ZsYellow1, under the regulation of the c-fos promoter, was expressed throughout the rat brain. A fiber-based confocal microscope that enabled deep brain imaging was utilized, and local field potentials were collected simultaneously. In the weeks following limb denervation in adult rats (n=10), sensory stimulation of the intact limb induced significant increases in c-fos gene expression in cells located in S1, both contralateral (affected, 27.6±3 cells) and ipsilateral (8.6±3 cells) to the injury, compared to controls (n=10, 13.4±3 and 1.0±1, respectively, p value<0.05). Thus, we demonstrated that injury activates cellular mechanisms that are involved in reshaping neuronal connections, and this may translate to neurorehabilitative potential.
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