1
|
Bhandare A, Haley M, Torrico Anderson V, Domingos LB, Lopes M, Corrêa SAL, Wall MJ. ArcKR expression modifies synaptic plasticity following epileptic activity: Differential effects with in vitro and in vivo seizure-induction protocols. Epilepsia 2024. [PMID: 38804501 DOI: 10.1111/epi.17981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 03/25/2024] [Accepted: 03/28/2024] [Indexed: 05/29/2024]
Abstract
OBJECTIVES Pathological forms of neural activity, such as epileptic seizures, modify the expression pattern of multiple proteins, leading to persistent changes in brain function. One such protein is activity-regulated cytoskeleton-associated protein (Arc), which is critically involved in protein-synthesis-dependent synaptic plasticity underlying learning and memory. In the present study, we have investigated how the expression of ArcKR, a form of Arc in which the ubiquitination sites have been mutated, resulting in slowed Arc degradation, modifies group I metabotropic glutamate receptor-mediated long-term depression (G1-mGluR-LTD) following seizures. METHODS We used a knock-in mice line that express ArcKR and two hyperexcitation models: an in vitro model, where hippocampal slices were exposed to zero Mg2+, 6 mM K+; and an in vivo model, where kainic acid was injected unilaterally into the hippocampus. In both models, field excitatory postsynaptic potentials (fEPSPs) were recorded from the CA1 region of hippocampal slices in response to Schaffer collateral stimulation and G1-mGluR-LTD was induced chemically with the group 1 mGluR agonist DHPG. RESULTS In the in vitro model, ArcKR expression enhanced the effects of seizure activity and increased the magnitude of G1-mGluR LTD, an effect that could be blocked with the mGluR5 antagonist MTEP. In the in vivo model, fEPSPs were significantly smaller in slices from ArcKR mice and were less contaminated by population spikes. In this model, the amount of G1-mGluR-LTD was significantly less in epileptic slices from ArcKR mice as compared to wildtype (WT) mice. SIGNIFICANCE We have shown that expression of ArcKR, a form of Arc in which degradation is reduced, significantly modulates the magnitude of G1-mGluR-LTD following epileptic seizures. However, the effect of ArcKR on LTD depends on the epileptic model used, with enhancement of LTD in an in vitro model and a reduction in the kainate mouse model.
Collapse
Affiliation(s)
- Amol Bhandare
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Maisy Haley
- School of Life Sciences, University of Warwick, Coventry, UK
| | | | - Luana B Domingos
- Bradford School of Pharmacy and Medical Sciences, University of Bradford, Bradford, UK
| | - Marcia Lopes
- Bradford School of Pharmacy and Medical Sciences, University of Bradford, Bradford, UK
| | - Sonia A L Corrêa
- Bradford School of Pharmacy and Medical Sciences, University of Bradford, Bradford, UK
- Department of Life Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, UK
| | - Mark J Wall
- School of Life Sciences, University of Warwick, Coventry, UK
| |
Collapse
|
2
|
Rahmi U, Goenawan H, Sylviana N, Setiawan I, Putri ST, Andriyani S, Fitriana LA. Exercise induction at expression immediate early gene (c-Fos, ARC, EGR-1) in the hippocampus: a systematic review. Dement Neuropsychol 2024; 18:e20230015. [PMID: 38628561 PMCID: PMC11019719 DOI: 10.1590/1980-5764-dn-2023-0015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 11/06/2023] [Accepted: 11/17/2023] [Indexed: 04/19/2024] Open
Abstract
The immediate early gene exhibits activation markers in the nervous system consisting of ARC, EGR-1, and c-Fos and is related to synaptic plasticity, especially in the hippocampus. Immediate early gene expression is affected by physical exercise, which induces direct ARC, EGR-1, and c-Fos expression. Objective To assess the impact of exercise, we conducted a literature study to determine the expression levels of immediate early genes (ARC, c-Fos, and EGR-1). Methods The databases accessed for online literature included PubMed-Medline, Scopus, and ScienceDirect. The original English articles were selected using the following keywords in the title: (Exercise OR physical activity) AND (c-Fos) AND (Hippocampus), (Exercise OR physical activity) AND (ARC) AND (Hippocampus), (Exercise OR physical activity) AND (EGR-1 OR zif268) AND (Hippocampus). Results Physical exercise can affect the expression of EGR-1, c-Fos, and ARC in the hippocampus, an important part of the brain involved in learning and memory. High-intensity physical exercise can increase c-Fos expression, indicating neural activation. Furthermore, the expression of the ARC gene also increases due to physical exercise. ARC is a gene that plays a role in synaptic plasticity and regulation of learning and memory, changes in synaptic structure and increased synaptic connections, while EGR-1 also plays a role in synaptic plasticity, a genetic change that affects learning and memory. Overall, exercise or regular physical exercise can increase the expression of ARC, c-Fos, and EGR-1 in the hippocampus. This reflects the changes in neuroplasticity and synaptic plasticity that occur in response to physical activity. These changes can improve cognitive function, learning, and memory. Conclusion c-Fos, EGR-1, and ARC expression increases in hippocampal neurons after exercise, enhancing synaptic plasticity and neurogenesis associated with learning and memory.
Collapse
Affiliation(s)
- Upik Rahmi
- Universitas Pendidikan Indonesia, Department of Nursing, Bandung, West Java, Indonesia
- Universitas Padjadjaran, Department of Medicine, Bandung, West Java, Indonesia
| | - Hanna Goenawan
- Universitas Padjadjaran, Department of Medicine, Bandung, West Java, Indonesia
| | - Nova Sylviana
- Universitas Padjadjaran, Department of Medicine, Bandung, West Java, Indonesia
| | - Iwan Setiawan
- Universitas Padjadjaran, Department of Medicine, Bandung, West Java, Indonesia
| | - Suci Tuty Putri
- Universitas Pendidikan Indonesia, Department of Nursing, Bandung, West Java, Indonesia
| | - Septian Andriyani
- Universitas Pendidikan Indonesia, Department of Nursing, Bandung, West Java, Indonesia
| | - Lisna Anisa Fitriana
- Universitas Pendidikan Indonesia, Department of Nursing, Bandung, West Java, Indonesia
| |
Collapse
|
3
|
Haley M, Bertrand J, Anderson VT, Fuad M, Frenguelli BG, Corrêa SAL, Wall MJ. Arc expression regulates long-term potentiation magnitude and metaplasticity in area CA1 of the hippocampus in ArcKR mice. Eur J Neurosci 2023; 58:4166-4180. [PMID: 37821126 DOI: 10.1111/ejn.16172] [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: 06/20/2023] [Revised: 09/18/2023] [Accepted: 09/26/2023] [Indexed: 10/13/2023]
Abstract
Expression of the immediate early gene Arc/Arg3.1 (Arc), a key mediator of synaptic plasticity, is enhanced by neural activity and then reduced by proteasome-dependent degradation. We have previously shown that the disruption of Arc degradation, in an Arc knock-in mouse (ArcKR), where the predominant Arc ubiquitination sites were mutated, reduced the threshold to induce, and also enhanced, the strength of Group I metabotropic glutamate receptor-mediated long-term depression (DHPG-LTD). Here, we have investigated if ArcKR expression changes long-term potentiation (LTP) in CA1 area of the hippocampus. As previously reported, there was no change in basal synaptic transmission at Schaffer collateral/commissural-CA1 (SC-CA1) synapses in ArcKR versus wild-type (WT) mice. There was, however, a significant increase in the amplitude of synaptically induced (with low frequency paired-pulse stimulation) LTD in ArcKR mice. Theta burst stimulation (TBS)-evoked LTP at SC-CA1 synapses was significantly reduced in ArcKR versus WT mice (after 2 h). Group 1 mGluR priming of LTP was abolished in ArcKR mice, which could also potentially contribute to a depression of LTP. Although high frequency stimulation (HFS)-induced LTP was not significantly different in ArcKR compared with WT mice (after 1 h), there was a phenotype in environmentally enriched mice, with the ratio of LTP to short-term potentiation (STP) significantly reduced in ArcKR mice. These findings support the hypothesis that Arc ubiquitination supports the induction and expression of LTP, likely via limiting Arc-dependent removal of AMPA receptors at synapses.
Collapse
Affiliation(s)
- Maisy Haley
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Jeanri Bertrand
- School of Life Sciences, University of Warwick, Coventry, UK
| | | | - Mukattar Fuad
- School of Life Sciences, University of Warwick, Coventry, UK
| | | | - Sonia A L Corrêa
- Faculty of Science and Engineering, Department of Life Sciences, John Dalton Building, Room E210, Manchester Metropolitan University, Manchester, UK
| | - Mark J Wall
- School of Life Sciences, University of Warwick, Coventry, UK
| |
Collapse
|
4
|
Lyons LC, Vanrobaeys Y, Abel T. Sleep and memory: The impact of sleep deprivation on transcription, translational control, and protein synthesis in the brain. J Neurochem 2023; 166:24-46. [PMID: 36802068 PMCID: PMC10919414 DOI: 10.1111/jnc.15787] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 01/31/2023] [Accepted: 02/07/2023] [Indexed: 02/20/2023]
Abstract
In countries around the world, sleep deprivation represents a widespread problem affecting school-age children, teenagers, and adults. Acute sleep deprivation and more chronic sleep restriction adversely affect individual health, impairing memory and cognitive performance as well as increasing the risk and progression of numerous diseases. In mammals, the hippocampus and hippocampus-dependent memory are vulnerable to the effects of acute sleep deprivation. Sleep deprivation induces changes in molecular signaling, gene expression and may cause changes in dendritic structure in neurons. Genome wide studies have shown that acute sleep deprivation alters gene transcription, although the pool of genes affected varies between brain regions. More recently, advances in research have drawn attention to differences in gene regulation between the level of the transcriptome compared with the pool of mRNA associated with ribosomes for protein translation following sleep deprivation. Thus, in addition to transcriptional changes, sleep deprivation also affects downstream processes to alter protein translation. In this review, we focus on the multiple levels through which acute sleep deprivation impacts gene regulation, highlighting potential post-transcriptional and translational processes that may be affected by sleep deprivation. Understanding the multiple levels of gene regulation impacted by sleep deprivation is essential for future development of therapeutics that may mitigate the effects of sleep loss.
Collapse
Affiliation(s)
- Lisa C Lyons
- Program in Neuroscience, Department of Biological Science, Florida State University, Tallahassee, Florida, USA
| | - Yann Vanrobaeys
- Department of Neuroscience and Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
- Iowa Neuroscience Institute, Iowa City, Iowa, USA
- Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, Iowa, USA
| | - Ted Abel
- Department of Neuroscience and Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
- Iowa Neuroscience Institute, Iowa City, Iowa, USA
| |
Collapse
|
5
|
Dysregulated Signaling at Postsynaptic Density: A Systematic Review and Translational Appraisal for the Pathophysiology, Clinics, and Antipsychotics' Treatment of Schizophrenia. Cells 2023; 12:cells12040574. [PMID: 36831241 PMCID: PMC9954794 DOI: 10.3390/cells12040574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/07/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023] Open
Abstract
Emerging evidence from genomics, post-mortem, and preclinical studies point to a potential dysregulation of molecular signaling at postsynaptic density (PSD) in schizophrenia pathophysiology. The PSD that identifies the archetypal asymmetric synapse is a structure of approximately 300 nm in diameter, localized behind the neuronal membrane in the glutamatergic synapse, and constituted by more than 1000 proteins, including receptors, adaptors, kinases, and scaffold proteins. Furthermore, using FASS (fluorescence-activated synaptosome sorting) techniques, glutamatergic synaptosomes were isolated at around 70 nm, where the receptors anchored to the PSD proteins can diffuse laterally along the PSD and were stabilized by scaffold proteins in nanodomains of 50-80 nm at a distance of 20-40 nm creating "nanocolumns" within the synaptic button. In this context, PSD was envisioned as a multimodal hub integrating multiple signaling-related intracellular functions. Dysfunctions of glutamate signaling have been postulated in schizophrenia, starting from the glutamate receptor's interaction with scaffolding proteins involved in the N-methyl-D-aspartate receptor (NMDAR). Despite the emerging role of PSD proteins in behavioral disorders, there is currently no systematic review that integrates preclinical and clinical findings addressing dysregulated PSD signaling and translational implications for antipsychotic treatment in the aberrant postsynaptic function context. Here we reviewed a critical appraisal of the role of dysregulated PSD proteins signaling in the pathophysiology of schizophrenia, discussing how antipsychotics may affect PSD structures and synaptic plasticity in brain regions relevant to psychosis.
Collapse
|
6
|
Qi C, Luo LD, Feng I, Ma S. Molecular mechanisms of synaptogenesis. Front Synaptic Neurosci 2022; 14:939793. [PMID: 36176941 PMCID: PMC9513053 DOI: 10.3389/fnsyn.2022.939793] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/27/2022] [Indexed: 11/29/2022] Open
Abstract
Synapses are the basic units for information processing and storage in the nervous system. It is only when the synaptic connection is established, that it becomes meaningful to discuss the structure and function of a circuit. In humans, our unparalleled cognitive abilities are correlated with an increase in the number of synapses. Additionally, genes involved in synaptogenesis are also frequently associated with neurological or psychiatric disorders, suggesting a relationship between synaptogenesis and brain physiology and pathology. Thus, understanding the molecular mechanisms of synaptogenesis is the key to the mystery of circuit assembly and neural computation. Furthermore, it would provide therapeutic insights for the treatment of neurological and psychiatric disorders. Multiple molecular events must be precisely coordinated to generate a synapse. To understand the molecular mechanisms underlying synaptogenesis, we need to know the molecular components of synapses, how these molecular components are held together, and how the molecular networks are refined in response to neural activity to generate new synapses. Thanks to the intensive investigations in this field, our understanding of the process of synaptogenesis has progressed significantly. Here, we will review the molecular mechanisms of synaptogenesis by going over the studies on the identification of molecular components in synapses and their functions in synaptogenesis, how cell adhesion molecules connect these synaptic molecules together, and how neural activity mobilizes these molecules to generate new synapses. Finally, we will summarize the human-specific regulatory mechanisms in synaptogenesis and results from human genetics studies on synaptogenesis and brain disorders.
Collapse
Affiliation(s)
- Cai Qi
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, United States
- *Correspondence: Cai Qi,
| | - Li-Da Luo
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, United States
- Department of Cellular and Molecular Physiology, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, United States
| | - Irena Feng
- Boston University School of Medicine, Boston, MA, United States
| | - Shaojie Ma
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, United States
| |
Collapse
|
7
|
Barman B, Kushwaha A, Thakur MK. Muscarinic Acetylcholine Receptors-Mediated Activation of PKC Restores the Hippocampal Immediate Early Gene Expression and CREB Phosphorylation in Scopolamine-Induced Amnesic Mice. Mol Neurobiol 2022; 59:5722-5733. [DOI: 10.1007/s12035-022-02940-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 06/23/2022] [Indexed: 10/17/2022]
|
8
|
Markússon S, Hallin EI, Bustad HJ, Raasakka A, Xu J, Muruganandam G, Loris R, Martinez A, Bramham CR, Kursula P. High-affinity anti-Arc nanobodies provide tools for structural and functional studies. PLoS One 2022; 17:e0269281. [PMID: 35671319 PMCID: PMC9173642 DOI: 10.1371/journal.pone.0269281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 05/17/2022] [Indexed: 11/19/2022] Open
Abstract
Activity-regulated cytoskeleton-associated protein (Arc) is a multidomain protein of retroviral origin with a vital role in the regulation of synaptic plasticity and memory formation in mammals. However, the mechanistic and structural basis of Arc function is poorly understood. Arc has an N-terminal domain (NTD) involved in membrane binding and a C-terminal domain (CTD) that binds postsynaptic protein ligands. In addition, the NTD and CTD both function in Arc oligomerisation, including assembly of retrovirus-like capsids involved in intercellular signalling. To obtain new tools for studies on Arc structure and function, we produced and characterised six high-affinity anti-Arc nanobodies (Nb). The CTD of rat and human Arc were both crystallised in ternary complexes with two Nbs. One Nb bound deep into the stargazin-binding pocket of Arc CTD and suggested competitive binding with Arc ligand peptides. The crystallisation of the human Arc CTD in two different conformations, accompanied by SAXS data and molecular dynamics simulations, paints a dynamic picture of the mammalian Arc CTD. The collapsed conformation closely resembles Drosophila Arc in capsids, suggesting that we have trapped a capsid-like conformation of the human Arc CTD. Our data obtained with the help of anti-Arc Nbs suggest that structural dynamics of the CTD and dimerisation of the NTD may promote the formation of capsids. Taken together, the recombinant high-affinity anti-Arc Nbs are versatile tools that can be further developed for studying mammalian Arc structure and function, as well as mechanisms of Arc capsid formation, both in vitro and in vivo. For example, the Nbs could serve as a genetically encoded tools for inhibition of endogenous Arc interactions in the study of neuronal function and plasticity.
Collapse
Affiliation(s)
| | - Erik I. Hallin
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | | | - Arne Raasakka
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Ju Xu
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Gopinath Muruganandam
- VIB-VUB Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Department of Bioengineering Sciences, Structural Biology Brussels, Vrije Universiteit Brussel, Brussel, Belgium
| | - Remy Loris
- VIB-VUB Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Department of Bioengineering Sciences, Structural Biology Brussels, Vrije Universiteit Brussel, Brussel, Belgium
| | - Aurora Martinez
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | | | - Petri Kursula
- Department of Biomedicine, University of Bergen, Bergen, Norway
- Faculty of Biochemistry and Molecular Medicine & Biocenter Oulu, University of Oulu, Oulu, Finland
- * E-mail:
| |
Collapse
|
9
|
Lee JQ, McHugh R, Morgan E, Sutherland RJ, McDonald RJ. Behaviour-driven Arc expression is greater in dorsal than ventral CA1 regardless of task or sex differences. Behav Brain Res 2022; 423:113790. [PMID: 35149121 DOI: 10.1016/j.bbr.2022.113790] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 01/31/2022] [Accepted: 02/06/2022] [Indexed: 11/30/2022]
Abstract
Evidence from genetic, behavioural, anatomical, and physiological study suggests that the hippocampus functionally differs across its longitudinal (dorsoventral or septotemporal) axis. Although, how to best characterize functional and representational differences in the hippocampus across its long axis remains unclear. While some suggest that the hippocampus can be divided into dorsal and ventral subregions that support distinct cognitive functions, others posit that these regions vary in their granularity of representation, wherein spatial-temporal resolution decreases in the ventral (temporal) direction. Importantly, the cognitive and granular hypotheses also make distinct predictions on cellular recruitment dynamics under conditions when animals perform tasks with qualitatively different cognitive-behavioural demands. One interpretation of the cognitive function account implies that dorsal and ventral cellular recruitment differs depending on relevant behavioural demands, while the granularity account suggests similar recruitment dynamics regardless of the nature of the task performed. Here, we quantified cellular recruitment with the immediate early gene (IEG) Arc across the entire longitudinal CA1 axis in female and male rats performing spatial- and fear-guided memory tasks. Our results show that recruitment is greater in dorsal than ventral CA1 regardless of task or sex, and thus support a granular view of hippocampal function across the long axis. We further discuss how future experiments might determine the relative contributions of cognitive function and granularity of representation to neuronal activity dynamics in hippocampal circuits.
Collapse
Affiliation(s)
- J Quinn Lee
- Department of Neuroscience, Science Commons, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 6T5, Canada; Department of Psychiatry, Douglas Hospital Research Centre, McGill University, 6875 Boulevard LaSalle, Verdun, QC H4H 1R3, Canada.
| | - Rebecca McHugh
- Department of Neuroscience, Science Commons, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 6T5, Canada
| | - Erik Morgan
- Department of Neuroscience, Science Commons, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 6T5, Canada
| | - Robert J Sutherland
- Department of Neuroscience, Science Commons, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 6T5, Canada
| | - Robert J McDonald
- Department of Neuroscience, Science Commons, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 6T5, Canada
| |
Collapse
|
10
|
mRNA Trafficking in the Nervous System: A Key Mechanism of the Involvement of Activity-Regulated Cytoskeleton-Associated Protein (Arc) in Synaptic Plasticity. Neural Plast 2021; 2021:3468795. [PMID: 34603440 PMCID: PMC8486535 DOI: 10.1155/2021/3468795] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/15/2021] [Accepted: 09/07/2021] [Indexed: 12/18/2022] Open
Abstract
Synaptic activity mediates information storage and memory consolidation in the brain and requires a fast de novo synthesis of mRNAs in the nucleus and proteins in synapses. Intracellular localization of a protein can be achieved by mRNA trafficking and localized translation. Activity-regulated cytoskeleton-associated protein (Arc) is a master regulator of synaptic plasticity and plays an important role in controlling large signaling networks implicated in learning, memory consolidation, and behavior. Transcription of the Arc gene may be induced by a short behavioral event, resulting in synaptic activation. Arc mRNA is exported into the cytoplasm and can be trafficked into the dendrite of an activated synapse where it is docked and translated. The structure of Arc is similar to the viral GAG (group-specific antigen) protein, and phylogenic analysis suggests that Arc may originate from the family of Ty3/Gypsy retrotransposons. Therefore, Arc might evolve through “domestication” of retroviruses. Arc can form a capsid-like structure that encapsulates a retrovirus-like sentence in the 3′-UTR (untranslated region) of Arc mRNA. Such complex can be loaded into extracellular vesicles and transported to other neurons or muscle cells carrying not only genetic information but also regulatory signals within neuronal networks. Therefore, Arc mRNA inter- and intramolecular trafficking is essential for the modulation of synaptic activity required for memory consolidation and cognitive functions. Recent studies with single-molecule imaging in live neurons confirmed and extended the role of Arc mRNA trafficking in synaptic plasticity.
Collapse
|
11
|
Vitamin B 12-folic acid supplementation regulates neuronal immediate early gene expression and improves hippocampal dendritic arborization and memory in old male mice. Neurochem Int 2021; 150:105181. [PMID: 34509560 DOI: 10.1016/j.neuint.2021.105181] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 09/05/2021] [Accepted: 09/07/2021] [Indexed: 01/19/2023]
Abstract
As the relationship among diet, brain aging and memory is complex, it provides ample opportunity for research in multiple directions including behaviour, epigenetics and neuroplasticity. Nutritional deficiencies together with genetic and environmental factors are the major cause of many age-associated pathologies including memory loss. A compromised vitamin B12-folate status in older people is highly prevalent worldwide. Researchers have established a close association between the adequate level of B12-folate and the maintenance of cognitive brain functions. One of the main reasons for age-associated memory loss is downregulation of neuronal immediate early genes (nIEGs). Therefore, we hypothesize here that vitamin B12-folic acid supplementation in old mice can improve memory by altering the expression status of nIEGs. To check this, 72-week-old male Swiss albino mice were orally administered with 2 μg of vitamin B12 and 22 μg of folic acid/mouse/day for eight weeks. Such supplementation improved recognition memory in old and altered the expression of nIEGs. The expression of nIEGs was further found to be regulated by changes in DNA methylation at their promoter regions and CREB phosphorylation (pCREB). In addition, Golgi-Cox staining showed significant improvement in dendritic length, number of branching points and spine density of hippocampal CA1 pyramidal neurons by B12-folic acid supplementation. Taken together, these findings suggest that vitamin B12-folic acid supplementation regulates nIEGs expression and improves dendritic arborization of hippocampal neurons and memory in old male mice.
Collapse
|
12
|
Titlow J, Robertson F, Järvelin A, Ish-Horowicz D, Smith C, Gratton E, Davis I. Syncrip/hnRNP Q is required for activity-induced Msp300/Nesprin-1 expression and new synapse formation. J Cell Biol 2020; 219:133707. [PMID: 32040548 PMCID: PMC7055005 DOI: 10.1083/jcb.201903135] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 08/21/2019] [Accepted: 12/12/2019] [Indexed: 01/09/2023] Open
Abstract
Memory and learning involve activity-driven expression of proteins and cytoskeletal reorganization at new synapses, requiring posttranscriptional regulation of localized mRNA a long distance from corresponding nuclei. A key factor expressed early in synapse formation is Msp300/Nesprin-1, which organizes actin filaments around the new synapse. How Msp300 expression is regulated during synaptic plasticity is poorly understood. Here, we show that activity-dependent accumulation of Msp300 in the postsynaptic compartment of the Drosophila larval neuromuscular junction is regulated by the conserved RNA binding protein Syncrip/hnRNP Q. Syncrip (Syp) binds to msp300 transcripts and is essential for plasticity. Single-molecule imaging shows that msp300 is associated with Syp in vivo and forms ribosome-rich granules that contain the translation factor eIF4E. Elevated neural activity alters the dynamics of Syp and the number of msp300:Syp:eIF4E RNP granules at the synapse, suggesting that these particles facilitate translation. These results introduce Syp as an important early acting activity-dependent regulator of a plasticity gene that is strongly associated with human ataxias.
Collapse
Affiliation(s)
- Joshua Titlow
- Department of Biochemistry, University of Oxford, Oxford, UK
| | | | - Aino Järvelin
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - David Ish-Horowicz
- Department of Biochemistry, University of Oxford, Oxford, UK.,Medical Research Council Lab for Molecular Cell Biology, University College London, London, UK
| | - Carlas Smith
- Centre for Neural Circuits and Behaviour, University of Oxford, Oxford, UK
| | - Enrico Gratton
- Laboratory for Fluorescence Dynamics, University of California Irvine, Irvine, CA
| | - Ilan Davis
- Department of Biochemistry, University of Oxford, Oxford, UK
| |
Collapse
|
13
|
Boldridge M, Shimabukuro J, Nakamatsu K, Won C, Jansen C, Turner H, Wang L. Characterization of the C-terminal tail of the Arc protein. PLoS One 2020; 15:e0239870. [PMID: 32991626 PMCID: PMC7523963 DOI: 10.1371/journal.pone.0239870] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 09/15/2020] [Indexed: 12/22/2022] Open
Abstract
The activity-regulated cytoskeleton-associate protein Arc (or Arg3.1) is specifically linked to memory formation and a number of cognitive disorders, including Alzheimer's disease and schizophrenia. Since the discovery of Arc in 1995, extensive research has been conducted on the protein to identify its function and mechanisms of action, with solving the structure of Arc as a major goal. However, the Arc protein tends to self-oligomerize in vitro, and is difficult to crystallize. These properties have hindered efforts to obtain the structure of the full-length, whole protein Arc. As an alternative approach, we and others, have sought to solve the structures of various subdomain proteins of Arc, including the N-lobe, C-lobe, and capsid domain (N-lobe + C-lobe). In this study, we characterized the C-terminal tail of Arc using integrated bioinformatic and structural biology techniques. We compared the sequences of Arc proteins in different mammal species and found that the amino-acid composition in the C-terminal tail region has a significantly higher degree of variation rate than the rest of the protein. Structural prediction programs suggested that the C-terminal tail is structurally disordered. Chemical shift analysis based on solution NMR spectra confirmed that the C-terminal tail has a random coil (disordered) structure, and the tail starts from the residue D357. Furthermore, the NMR spectra showed that the C-terminal tail has minimum (if any) interaction with its neighboring capsid domain in Arc. This study fills gaps in our specific understanding of the structural nature and functional contributions of the Arc C-terminus.
Collapse
Affiliation(s)
- Melissa Boldridge
- Department of Natural Sciences, Hawaii Pacific University, Honolulu, Hawaii, United States of America
| | - Jody Shimabukuro
- Department of Natural Sciences, Hawaii Pacific University, Honolulu, Hawaii, United States of America
| | - Keith Nakamatsu
- Department of Natural Sciences, Windward Community College, Kaneohe, Hawaii, United States of America
| | - Christian Won
- Department of Natural Sciences, Windward Community College, Kaneohe, Hawaii, United States of America
| | - Chad Jansen
- Laboratory of Immunology and Signal Transduction, School of Natural Sciences and Mathematics, Chaminade University, Honolulu, Hawaii, United States of America
| | - Helen Turner
- Laboratory of Immunology and Signal Transduction, School of Natural Sciences and Mathematics, Chaminade University, Honolulu, Hawaii, United States of America
| | - Lei Wang
- Department of Natural Sciences, Hawaii Pacific University, Honolulu, Hawaii, United States of America
| |
Collapse
|
14
|
Doll CA, Yergert KM, Appel BH. The RNA binding protein fragile X mental retardation protein promotes myelin sheath growth. Glia 2019; 68:495-508. [PMID: 31626382 DOI: 10.1002/glia.23731] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 09/20/2019] [Accepted: 09/22/2019] [Indexed: 12/13/2022]
Abstract
During development, oligodendrocytes in the central nervous system extend a multitude of processes that wrap axons with myelin. The highly polarized oligodendrocytes generate myelin sheaths on many different axons, which are far removed from the cell body. Neurons use RNA binding proteins to transport, stabilize, and locally translate mRNA in distal domains of neurons. Local synthesis of synaptic proteins during neurodevelopment facilitates the rapid structural and functional changes underlying neural plasticity and avoids extensive protein transport. We hypothesize that RNA binding proteins also regulate local mRNA regulation in oligodendrocytes to promote myelin sheath growth. Fragile X mental retardation protein (FMRP), an RNA binding protein that plays essential roles in the growth and maturation of neurons, is also expressed in oligodendrocytes. To determine whether oligodendrocytes require FMRP for myelin sheath development, we examined fmr1-/- mutant zebrafish and drove FMR1 expression specifically in oligodendrocytes. We found oligodendrocytes in fmr1-/- mutants developed myelin sheaths of diminished length, a phenotype that can be autonomously rescued in oligodendrocytes with FMR1 expression. Myelin basic protein (Mbp), an essential myelin protein, was reduced in myelin tracts of fmr1-/- mutants, but loss of FMRP function did not impact the localization of mbpa transcript in myelin. Finally, expression of FMR1-I304N, a missense allele that abrogates FMRP association with ribosomes, failed to rescue fmr1-/- mutant sheath growth and induced short myelin sheaths in oligodendrocytes of wild-type larvae. Taken together, these data suggest that FMRP promotes sheath growth through local regulation of translation.
Collapse
Affiliation(s)
- Caleb A Doll
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Katie M Yergert
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Bruce H Appel
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| |
Collapse
|
15
|
Livingstone RW, Elder MK, Barrett MC, Westlake CM, Peppercorn K, Tate WP, Abraham WC, Williams JM. Secreted Amyloid Precursor Protein-Alpha Promotes Arc Protein Synthesis in Hippocampal Neurons. Front Mol Neurosci 2019; 12:198. [PMID: 31474829 PMCID: PMC6702288 DOI: 10.3389/fnmol.2019.00198] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 07/30/2019] [Indexed: 12/22/2022] Open
Abstract
Secreted amyloid precursor protein-α (sAPPα) is a neuroprotective and memory-enhancing molecule, however, the mechanisms through which sAPPα promotes these effects are not well understood. Recently, we have shown that sAPPα enhances cell-surface expression of glutamate receptors. Activity-related cytoskeletal-associated protein Arc (Arg3.1) is an immediate early gene capable of modulating long-term potentiation, long-term depression and homeostatic plasticity through regulation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor localization. Accordingly, we hypothesized that sAPPα may enhance synaptic plasticity, in part, by the de novo synthesis of Arc. Using primary cortical and hippocampal neuronal cultures we found that sAPPα (1 nM, 2 h) enhances levels of Arc mRNA and protein. Arc protein levels were increased in both the neuronal somata and dendrites in a Ca2+/calmodulin-dependent protein kinase II-dependent manner. Additionally, dendritic Arc expression was dependent upon activation of mitogen-activated protein kinase and protein kinase G. The enhancement of dendritic Arc protein was significantly reduced by antagonism of N-methyl-D-aspartate (NMDA) and nicotinic acetylcholine (α7nACh) receptors, and fully eliminated by dual application of these antagonists. This effect was further corroborated in area CA1 of acute hippocampal slices. These data suggest sAPPα-regulated plasticity within hippocampal neurons is mediated by cooperation of NMDA and α7nACh receptors to engage a cascade of signal transduction molecules to enhance the transcription and translation of Arc.
Collapse
Affiliation(s)
- Rhys W Livingstone
- Department of Anatomy, Brain Health Research Centre, Brain Research New Zealand, Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand
| | - Megan K Elder
- Department of Anatomy, Brain Health Research Centre, Brain Research New Zealand, Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand
| | - Maya C Barrett
- Department of Anatomy, Brain Health Research Centre, Brain Research New Zealand, Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand
| | - Courteney M Westlake
- Department of Anatomy, Brain Health Research Centre, Brain Research New Zealand, Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand
| | - Katie Peppercorn
- Department of Biochemistry, Brain Health Research Centre, Brain Research New Zealand, Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand
| | - Warren P Tate
- Department of Biochemistry, Brain Health Research Centre, Brain Research New Zealand, Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand
| | - Wickliffe C Abraham
- Department of Psychology, Brain Health Research Centre, Brain Research New Zealand, Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand
| | - Joanna M Williams
- Department of Anatomy, Brain Health Research Centre, Brain Research New Zealand, Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand
| |
Collapse
|
16
|
Nielsen LD, Pedersen CP, Erlendsson S, Teilum K. The Capsid Domain of Arc Changes Its Oligomerization Propensity through Direct Interaction with the NMDA Receptor. Structure 2019; 27:1071-1081.e5. [DOI: 10.1016/j.str.2019.04.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 02/28/2019] [Accepted: 03/31/2019] [Indexed: 12/20/2022]
|
17
|
Bisagno V, Cadet JL. Expression of immediate early genes in brain reward circuitries: Differential regulation by psychostimulant and opioid drugs. Neurochem Int 2018; 124:10-18. [PMID: 30557593 DOI: 10.1016/j.neuint.2018.12.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 11/27/2018] [Accepted: 12/13/2018] [Indexed: 12/22/2022]
Abstract
Although some of the clinical manifestations of substance use disorders might be superficially similar, it is highly likely that different classes of abused drugs including opioids (heroin, morphine, and oxycodone, other opioids) and psychostimulants (cocaine and amphetamines) cause different neuroadaptations in various brain regions dependent in the distribution and concentration of their biochemical sites of actions. In fact, different molecular networks are indeed impacted by acute and chronic administration of addictive substances. Some of the genes whose expression is influenced by the administration of these substances are immediate-early genes (IEGs). IEGs include classes of low expression genes that can become very highly induced within seconds or minutes of activation by endogenous or exogenous stimuli. These IEGs might play important roles in activating target genes that regulate adaptations implicated in the behavioral manifestations diagnosed as addiction. Therefore, the purpose of this review is to provide an overview of recent data on the effects of psychostimulants and opioids on IEG expression in the brain. The review documents some contrasting effects of these classes of drugs on gene expression and indicates that further studies are necessary to identify the specific effects of each drug class when trying to predict clinical responses to therapeutic agents.
Collapse
Affiliation(s)
- Veronica Bisagno
- Instituto de Investigaciones Farmacológicas (ININFA-UBA-CONICET), Junín 956, piso 5, C1113, Buenos Aires, Argentina
| | - Jean Lud Cadet
- NIDA Intramural Program, Molecular Neuropsychiatry Research Branch, 251 Bayview Boulevard, Baltimore, MD, 21224, USA.
| |
Collapse
|
18
|
Effects of stressor controllability on transcriptional levels of c-fos, Arc, and brain-derived neurotrophic factor in mouse amygdala and medial prefrontal cortex. Neuroreport 2018; 29:112-117. [PMID: 29135807 DOI: 10.1097/wnr.0000000000000919] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Controllability is an important factor in determining stress outcomes. Uncontrollable stress is associated with the development of psychopathology such as post-traumatic stress disorder, whereas controllable stress is associated with adaptive stress responses and positive outcomes. In this study, we investigated how controllability affects poststress neurobiology by assessing transcriptional levels of activity-dependent genes in medial prefrontal cortex (mPFC) and amygdala, regions important in mediating stress outcomes. Mice were subjected to either escapable shock (ES) or yoked inescapable shock (IS) as models of controllable and uncontrollable stress, respectively. Immediately (0 h) or at 2 h after shock training (20 trials; 0.5 mA, 5.0 s maximum duration; 1.0 min interstimulus interval), mice were killed, and we interrogated expression levels of the immediate-early genes, c-fos and Arc, and a delayed primary response gene, brain-derived neurotrophic factor, in mPFC, amygdala, and somatosensory cortex (a control region), using real-time reverse transcription quantitative PCR (RT qPCR). We found ES-associated up-regulation of brain-derived neurotrophic factor in amygdala as well as in mPFC. IS suppressed c-fos in mPFC (0 h) but induced more Arc in amygdala (2 h) in comparison with ES. Freezing, an index of fear memory, and serum level corticosterone, an index of the stress response, did not differ between mice trained with ES or IS. The data are discussed with respect to the potential functional involvements of the amygdala and mPFC in mediating differential outcomes of controllable and uncontrollable stress.
Collapse
|
19
|
Kramer EE, Steadman PE, Epp JR, Frankland PW, Josselyn SA. Assessing Individual Neuronal Activity Across the Intact Brain: Using Hybridization Chain Reaction (HCR) to DetectArcmRNA Localized to the Nucleus in Volumes of Cleared Brain Tissue. ACTA ACUST UNITED AC 2018; 84:e49. [DOI: 10.1002/cpns.49] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Emily E. Kramer
- Program in Neurosciences and Mental Health, Hospital for Sick Children; Toronto Ontario Canada
- Institute of Medical Sciences, University of Toronto; Toronto Ontario Canada
| | - Patrick E. Steadman
- Program in Neurosciences and Mental Health, Hospital for Sick Children; Toronto Ontario Canada
- Institute of Medical Sciences, University of Toronto; Toronto Ontario Canada
| | - Jonathan R. Epp
- Program in Neurosciences and Mental Health, Hospital for Sick Children; Toronto Ontario Canada
- Department of Cell Biology and Anatomy, University of Calgary; Calgary Alberta Canada
- Current address: Hotchkiss Brain Institute, Cumming School of Medicine; Calgary Alberta Canada
| | - Paul W. Frankland
- Program in Neurosciences and Mental Health, Hospital for Sick Children; Toronto Ontario Canada
- Institute of Medical Sciences, University of Toronto; Toronto Ontario Canada
- Department of Psychology, University of Toronto; Toronto Ontario Canada
- Department of Physiology, University of Toronto; Toronto Ontario Canada
- Brain, Mind & Consciousness Program, Canadian Institute for Advanced Research; Toronto Ontario Canada. Child & Brain Development Program, Canadian Institute for Advanced Research; Toronto Ontario Canada
| | - Sheena A. Josselyn
- Program in Neurosciences and Mental Health, Hospital for Sick Children; Toronto Ontario Canada
- Institute of Medical Sciences, University of Toronto; Toronto Ontario Canada
- Department of Psychology, University of Toronto; Toronto Ontario Canada
- Department of Physiology, University of Toronto; Toronto Ontario Canada
- Brain, Mind & Consciousness Program, Canadian Institute for Advanced Research; Toronto Ontario Canada. Child & Brain Development Program, Canadian Institute for Advanced Research; Toronto Ontario Canada
| |
Collapse
|
20
|
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: 210] [Impact Index Per Article: 35.0] [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.
Collapse
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
| |
Collapse
|
21
|
de Bartolomeis A, Buonaguro EF, Latte G, Rossi R, Marmo F, Iasevoli F, Tomasetti C. Immediate-Early Genes Modulation by Antipsychotics: Translational Implications for a Putative Gateway to Drug-Induced Long-Term Brain Changes. Front Behav Neurosci 2017; 11:240. [PMID: 29321734 PMCID: PMC5732183 DOI: 10.3389/fnbeh.2017.00240] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 11/22/2017] [Indexed: 12/12/2022] Open
Abstract
An increasing amount of research aims at recognizing the molecular mechanisms involved in long-lasting brain architectural changes induced by antipsychotic treatments. Although both structural and functional modifications have been identified following acute antipsychotic administration in humans, currently there is scarce knowledge on the enduring consequences of these acute changes. New insights in immediate-early genes (IEGs) modulation following acute or chronic antipsychotic administration may help to fill the gap between primary molecular response and putative long-term changes. Moreover, a critical appraisal of the spatial and temporal patterns of IEGs expression may shed light on the functional "signature" of antipsychotics, such as the propensity to induce motor side effects, the potential neurobiological mechanisms underlying the differences between antipsychotics beyond D2 dopamine receptor affinity, as well as the relevant effects of brain region-specificity in their mechanisms of action. The interest for brain IEGs modulation after antipsychotic treatments has been revitalized by breakthrough findings such as the role of early genes in schizophrenia pathophysiology, the involvement of IEGs in epigenetic mechanisms relevant for cognition, and in neuronal mapping by means of IEGs expression profiling. Here we critically review the evidence on the differential modulation of IEGs by antipsychotics, highlighting the association between IEGs expression and neuroplasticity changes in brain regions impacted by antipsychotics, trying to elucidate the molecular mechanisms underpinning the effects of this class of drugs on psychotic, cognitive and behavioral symptoms.
Collapse
Affiliation(s)
- Andrea de Bartolomeis
- Laboratory of Molecular and Translational Psychiatry and Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Odontostomatology, University School of Medicine "Federico II", Naples, Italy
| | - Elisabetta F Buonaguro
- Laboratory of Molecular and Translational Psychiatry and Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Odontostomatology, University School of Medicine "Federico II", Naples, Italy
| | - Gianmarco Latte
- Laboratory of Molecular and Translational Psychiatry and Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Odontostomatology, University School of Medicine "Federico II", Naples, Italy
| | - Rodolfo Rossi
- Laboratory of Molecular and Translational Psychiatry and Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Odontostomatology, University School of Medicine "Federico II", Naples, Italy
| | - Federica Marmo
- Laboratory of Molecular and Translational Psychiatry and Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Odontostomatology, University School of Medicine "Federico II", Naples, Italy
| | - Felice Iasevoli
- Laboratory of Molecular and Translational Psychiatry and Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Odontostomatology, University School of Medicine "Federico II", Naples, Italy
| | - Carmine Tomasetti
- Laboratory of Molecular and Translational Psychiatry and Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Sciences and Odontostomatology, University School of Medicine "Federico II", Naples, Italy
| |
Collapse
|
22
|
Okuno H, Minatohara K, Bito H. Inverse synaptic tagging: An inactive synapse-specific mechanism to capture activity-induced Arc/arg3.1 and to locally regulate spatial distribution of synaptic weights. Semin Cell Dev Biol 2017; 77:43-50. [PMID: 28939038 DOI: 10.1016/j.semcdb.2017.09.025] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 09/15/2017] [Accepted: 09/18/2017] [Indexed: 12/22/2022]
Abstract
Long-lasting forms of synaptic plasticity such as long-term potentiation (LTP) and long-term depression (LTD) are fundamental cellular mechanisms underlying learning and memory. The synaptic tagging and capture (STC) hypothesis has provided a theoretical framework on how products of activity-dependent genes may interact with potentiated synapses to facilitate and maintain such long-lasting synaptic plasticity. Although Arc/arg3.1 was initially assumed to participate in STC processes during LTP, accumulating evidence indicated that Arc/arg3.1 might rather contribute in weakening of synaptic weights than in their strengthening. In particular, analyses of Arc/Arg3.1 protein dynamics and function in the dendrites after plasticity-inducing stimuli have revealed a new type of inactivity-dependent redistribution of synaptic weights, termed "inverse synaptic tagging". The original synaptic tagging and inverse synaptic tagging likely co-exist and are mutually non-exclusive mechanisms, which together may help orchestrate the redistribution of synaptic weights and promote the enhancement and maintenance of their contrast between potentiated and non-potentiated synapses during the late phase of long-term synaptic plasticity. In this review, we describe the inverse synaptic tagging mechanism that controls synaptic dynamics of Arc/Arg3.1, an immediate early gene product which is captured and preferentially targeted to non-potentiated synapses, and discuss its impact on neuronal circuit refinement and cognitive function.
Collapse
Affiliation(s)
- Hiroyuki Okuno
- SK Project, Medical Innovation Center, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
| | - Keiichiro Minatohara
- SK Project, Medical Innovation Center, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Haruhiko Bito
- Department of Neurochemistry, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.
| |
Collapse
|
23
|
Honjoh S, de Vivo L, Okuno H, Bito H, Tononi G, Cirelli C. Higher Arc Nucleus-to-Cytoplasm Ratio during Sleep in the Superficial Layers of the Mouse Cortex. Front Neural Circuits 2017; 11:60. [PMID: 28878629 PMCID: PMC5572345 DOI: 10.3389/fncir.2017.00060] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 08/10/2017] [Indexed: 11/13/2022] Open
Abstract
The activity-regulated cytoskeleton associated protein Arc is strongly and quickly upregulated by neuronal activity, synaptic potentiation and learning. Arc entry in the synapse is followed by the endocytosis of glutamatergic AMPA receptors (AMPARs), and its nuclear accumulation has been shown in vitro to result in a small decline in the transcription of the GluA1 subunit of AMPARs. Since these effects result in a decline in synaptic strength, we asked whether a change in Arc dynamics may temporally correlate with sleep-dependent GluA1 down-regulation. We measured the ratio of nuclear to cytoplasmic Arc expression (Arc Nuc/Cyto) in the cerebral cortex of EGFP-Arc transgenic mice that were awake most of the night and then perfused immediately before lights on (W mice), or were awake most of the night and then allowed to sleep (S mice) or sleep deprived (SD mice) for the first 2 h of the light phase. In primary motor cortex (M1), neurons with high levels of nuclear Arc (High Arc cells) were present in all mice, but in these cells Arc Nuc/Cyto was higher in S mice than in W mice and, importantly, ~15% higher in S mice than in SD mice collected at the same time of day, ruling out circadian effects. Greater Arc Nuc/Cyto with sleep was observed in the superficial layers of M1, but not in the deep layers. In High Arc cells, Arc Nuc/Cyto was also ~15%-30% higher in S mice than in W and SD mice in the superficial layers of primary somatosensory cortex (S1) and cingulate cortex area 1 (Cg1). In High Arc Cells of Cg1, Arc Nuc/Cyto and cytoplasmic levels of GluA1 immunoreactivities in the soma were also negatively correlated, independent of behavioral state. Thus, Arc moves to the nucleus during both sleep and wake, but its nuclear to cytoplasmic ratio increases with sleep in the superficial layers of several cortical areas. It remains to be determined whether the relative increase in nuclear Arc contributes significantly to the overall decline in the strength of excitatory synapses that occurs during sleep. Similarly, it remains to be determined whether the entry of Arc into specific synapses is gated by sleep.
Collapse
Affiliation(s)
- Sakiko Honjoh
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, United States
| | - Luisa de Vivo
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, United States
| | - Hiroyuki Okuno
- Medical Innovation Center, Graduate School of Medicine, Kyoto UniversityKyoto, Japan
| | - Haruhiko Bito
- Department of Neurochemistry, Graduate School of Medicine, The University of TokyoTokyo, Japan
| | - Giulio Tononi
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, United States
| | - Chiara Cirelli
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, United States
| |
Collapse
|
24
|
Phillips C. Brain-Derived Neurotrophic Factor, Depression, and Physical Activity: Making the Neuroplastic Connection. Neural Plast 2017; 2017:7260130. [PMID: 28928987 PMCID: PMC5591905 DOI: 10.1155/2017/7260130] [Citation(s) in RCA: 240] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 07/18/2017] [Indexed: 12/14/2022] Open
Abstract
Brain-derived neurotrophic factor (BDNF) is a neurotrophin that is vital to the survival, growth, and maintenance of neurons in key brain circuits involved in emotional and cognitive function. Convergent evidence indicates that neuroplastic mechanisms involving BDNF are deleteriously altered in major depressive disorder (MDD) and animal models of stress. Herein, clinical and preclinical evidence provided that stress-induced depressive pathology contributes to altered BDNF level and function in persons with MDD and, thereby, disruptions in neuroplasticity at the regional and circuit level. Conversely, effective therapeutics that mitigate depressive-related symptoms (e.g., antidepressants and physical activity) optimize BDNF in key brain regions, promote neuronal health and recovery of function in MDD-related circuits, and enhance pharmacotherapeutic response. A greater knowledge of the interrelationship between BDNF, depression, therapeutic mechanisms of action, and neuroplasticity is important as it necessarily precedes the derivation and deployment of more efficacious treatments.
Collapse
|
25
|
Gandolfi D, Cerri S, Mapelli J, Polimeni M, Tritto S, Fuzzati-Armentero MT, Bigiani A, Blandini F, Mapelli L, D'Angelo E. Activation of the CREB/ c-Fos Pathway during Long-Term Synaptic Plasticity in the Cerebellum Granular Layer. Front Cell Neurosci 2017; 11:184. [PMID: 28701927 PMCID: PMC5487453 DOI: 10.3389/fncel.2017.00184] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 06/16/2017] [Indexed: 12/22/2022] Open
Abstract
The induction of long-term potentiation and depression (LTP and LTD) is thought to trigger gene expression and protein synthesis, leading to consolidation of synaptic and neuronal changes. However, while LTP and LTD have been proposed to play important roles for sensori-motor learning in the cerebellum granular layer, their association with these mechanisms remained unclear. Here, we have investigated phosphorylation of the cAMP-responsive element binding protein (CREB) and activation of the immediate early gene c-Fos pathway following the induction of synaptic plasticity by theta-burst stimulation (TBS) in acute cerebellar slices. LTP and LTD were localized using voltage-sensitive dye imaging (VSDi). At two time points following TBS (15 min and 120 min), corresponding to the early and late phases of plasticity, slices were fixed and processed to evaluate CREB phosphorylation (P-CREB) and c-FOS protein levels, as well as Creb and c-Fos mRNA expression. High levels of P-CREB and Creb/c-Fos were detected before those of c-FOS, as expected if CREB phosphorylation triggered gene expression followed by protein synthesis. No differences between control slices and slices stimulated with TBS were observed in the presence of an N-methyl-D-aspartate receptor (NMDAR) antagonist. Interestingly, activation of the CREB/c-Fos system showed a relevant degree of colocalization with long-term synaptic plasticity. These results show that NMDAR-dependent plasticity at the cerebellum input stage bears about transcriptional and post-transcriptional processes potentially contributing to cerebellar learning and memory consolidation.
Collapse
Affiliation(s)
- Daniela Gandolfi
- Neurophysiology Unit, Department of Brain and Behavioral Sciences, University of PaviaPavia, Italy.,Brain Connectivity Center, Fondazione Istituto Neurologico Nazionale Casimiro Mondino (IRCCS)Pavia, Italy
| | - Silvia Cerri
- Laboratory of Functional Neurochemistry, Center for Research in Neurodegenerative Diseases, Fondazione Istituto Neurologico Nazionale Casimiro Mondino (IRCCS)Pavia, Italy
| | - Jonathan Mapelli
- Neurophysiology Unit, Department of Brain and Behavioral Sciences, University of PaviaPavia, Italy.,Department of Biomedical, Metabolic and Neural Sciences, Center for Neuroscience and Neurotechnology, University of Modena and Reggio EmiliaModena, Italy
| | - Mariarosa Polimeni
- Department of Public Health, Experimental and Forensic Medicine, Human Anatomy Unit, University of PaviaPavia Italy
| | - Simona Tritto
- Neurophysiology Unit, Department of Brain and Behavioral Sciences, University of PaviaPavia, Italy
| | - Marie-Therese Fuzzati-Armentero
- Laboratory of Functional Neurochemistry, Center for Research in Neurodegenerative Diseases, Fondazione Istituto Neurologico Nazionale Casimiro Mondino (IRCCS)Pavia, Italy
| | - Albertino Bigiani
- Department of Biomedical, Metabolic and Neural Sciences, Center for Neuroscience and Neurotechnology, University of Modena and Reggio EmiliaModena, Italy
| | - Fabio Blandini
- Laboratory of Functional Neurochemistry, Center for Research in Neurodegenerative Diseases, Fondazione Istituto Neurologico Nazionale Casimiro Mondino (IRCCS)Pavia, Italy
| | - Lisa Mapelli
- Neurophysiology Unit, Department of Brain and Behavioral Sciences, University of PaviaPavia, Italy.,Museo Storico Della Fisica e Centro Studi e Ricerche Enrico FermiRome, Italy
| | - Egidio D'Angelo
- Neurophysiology Unit, Department of Brain and Behavioral Sciences, University of PaviaPavia, Italy.,Brain Connectivity Center, Fondazione Istituto Neurologico Nazionale Casimiro Mondino (IRCCS)Pavia, Italy
| |
Collapse
|
26
|
Aguilar-Arredondo A, López-Hernández F, García-Velázquez L, Arias C, Zepeda A. Behavior-associated Neuronal Activation After Kainic Acid-induced Hippocampal Neurotoxicity is Modulated in Time. Anat Rec (Hoboken) 2016; 300:425-432. [PMID: 27860379 DOI: 10.1002/ar.23513] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 05/02/2016] [Accepted: 05/23/2016] [Indexed: 12/26/2022]
Abstract
Kainic acid-induced (KA) hippocampal damage leads to neuronal death and further synaptic plasticity. Formation of aberrant as well as of functional connections after such procedure has been documented. However, the impact of such structural plasticity on cell activation along time after damage and in face of a behavioral demand has not been explored. We evaluated if the mRNA and protein levels of plasticity-related protein synaptophysin (Syp and SYP, respectively) and activity-regulated cytoskeleton-associated protein mRNA and protein levels (Arc and Arc, respectively) in the dentate gyrus were differentially modulated in time in response to a spatial-exploratory task after KA-induced hippocampal damage. In addition, we analyzed Arc+/NeuN+ immunopositive cells in the different experimental conditions. We infused KA intrahippocampally to young-adult rats and 10 or 30 days post-lesion (dpl) animals performed a hippocampus-activating spatial-exploratory task. Our results show that Syp mRNA levels significantly increase at 10dpl and return to control levels after 30dpl, whereas SYP protein levels are diminished at 10dpl, but significantly increase at 30dpl, as compared to 10dpl. Arc mRNA and protein levels are both increased at 30dpl as compared to sham. Also the number of NeuN+/Arc+ cells significantly increases at 30dpl in the group with a spatial-exploratory demand. These results provide information on the long-term modifications associated to structural plasticity and neuronal activation in the dentate gyrus after excitotoxic damage and in face of a spatial-exploratory behavior. Anat Rec, 300:425-432, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Andrea Aguilar-Arredondo
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, DF, México
| | - Fernanda López-Hernández
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, DF, México
| | - Lizbeth García-Velázquez
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, DF, México
| | - Clorinda Arias
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, DF, México
| | - Angélica Zepeda
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, DF, México
| |
Collapse
|
27
|
Lee S, Kang S, Kim J, Yoon S, Kim SH, Moon C. Enhanced expression of immediate-early genes in mouse hippocampus after trimethyltin treatment. Acta Histochem 2016; 118:679-684. [PMID: 27614947 DOI: 10.1016/j.acthis.2016.09.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/29/2016] [Accepted: 09/01/2016] [Indexed: 12/27/2022]
Abstract
Immediate-early genes (IEGs) are transiently and rapidly activated in response to various cellular stimuli. IEGs mediate diverse functions during pathophysiologic events by regulating cellular signal transduction. We investigated the temporal expression of several IEGs, including c-fos, early growth response protein-1 (Egr-1), and activity-regulated cytoskeleton-associated protein (Arc), in trimethyltin (TMT)-induced hippocampal neurodegeneration. Mice (7 weeks old, C57BL/6) administered TMT (2.6mg/kg intraperitoneally) presented severe neurodegenerative lesions in the dentate gyrus (DG) and showed behavioral seizure activity on days 1-4 post-treatment, after which the lesions and behavior recovered spontaneously over time. c-fos, Egr-1, and Arc mRNA and protein levels significantly increased in the mouse hippocampus after TMT treatment. Immunohistochemical analysis showed that nuclear c-fos expression increased mainly in the DG, whereas nuclear Egr-1 expression was increased extensively in cornu ammonis (CA) 1, CA3, and the DG after TMT treatment. Increased Arc levels were detected in the cellular somata/dendrites of the hippocampal subregions after TMT treatment. Therefore, we suggest that increased IEGs are associated with TMT-induced pathological events in mouse hippocampus.
Collapse
Affiliation(s)
- Sueun Lee
- Department of Veterinary Anatomy, College of Veterinary Medicine and BK21 Plus Project Team, Animal Medical Institute, Chonnam National University, Gwangju 61186, South Korea
| | - Sohi Kang
- Department of Veterinary Anatomy, College of Veterinary Medicine and BK21 Plus Project Team, Animal Medical Institute, Chonnam National University, Gwangju 61186, South Korea
| | - Juhwan Kim
- Department of Veterinary Anatomy, College of Veterinary Medicine and BK21 Plus Project Team, Animal Medical Institute, Chonnam National University, Gwangju 61186, South Korea
| | - Seongwook Yoon
- Department of Veterinary Anatomy, College of Veterinary Medicine and BK21 Plus Project Team, Animal Medical Institute, Chonnam National University, Gwangju 61186, South Korea
| | - Sung-Ho Kim
- Department of Veterinary Anatomy, College of Veterinary Medicine and BK21 Plus Project Team, Animal Medical Institute, Chonnam National University, Gwangju 61186, South Korea
| | - Changjong Moon
- Department of Veterinary Anatomy, College of Veterinary Medicine and BK21 Plus Project Team, Animal Medical Institute, Chonnam National University, Gwangju 61186, South Korea.
| |
Collapse
|
28
|
Jedlicka P, Deller T. Understanding the role of synaptopodin and the spine apparatus in Hebbian synaptic plasticity - New perspectives and the need for computational modeling. Neurobiol Learn Mem 2016; 138:21-30. [PMID: 27470091 DOI: 10.1016/j.nlm.2016.07.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 07/15/2016] [Accepted: 07/23/2016] [Indexed: 12/17/2022]
Abstract
Synaptopodin (SP) is a proline-rich actin-associated protein essential for the formation of a spine apparatus (SA) in dendritic spines. The SA consists of stacks of smooth endoplasmic reticulum (sER) contiguous with the meshwork of somatodendritic ER. Spines of SP-deficient mice contain sER but no SA, demonstrating that SP is necessary for the assembly of ER cisterns into the more complex SA organelle. Although the SA was described decades ago, its function was difficult to investigate and remained elusive, in part because reliable markers for the SA were missing. After SP was identified as an essential component and a reliable marker of the SA, a role of SP/SA in hippocampal synaptic plasticity could be firmly established using loss-of-function approaches. Further studies revealed that SP/SA participate in the regulation of Ca2+-dependent spine-specific Hebbian plasticity and in activity-dependent changes in the spine actin cytoskeleton. In this review we are summarizing recent progress made on SP/SA in Hebbian plasticity and discuss open questions such as causality, spatiotemporal dynamics and complementarity of SP/SA-dependent mechanisms. We are proposing that computational modeling of spine Ca2+-signaling and actin remodeling pathways could address some of these issues and could indicate future research directions. Moreover, reaction-diffusion simulations could help to identify key feedforward and feedback regulatory motifs regulating the switch between an LTP and an LTD signaling module in SP/SA-containing spines, thus helping to find a unified view of SP/SA action in Hebbian plasticity.
Collapse
Affiliation(s)
- Peter Jedlicka
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe University Frankfurt, D-60590 Frankfurt/Main, Germany.
| | - Thomas Deller
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe University Frankfurt, D-60590 Frankfurt/Main, Germany.
| |
Collapse
|
29
|
Fung LK, Reiss AL. Moving Toward Integrative, Multidimensional Research in Modern Psychiatry: Lessons Learned From Fragile X Syndrome. Biol Psychiatry 2016; 80:100-111. [PMID: 26868443 PMCID: PMC4912939 DOI: 10.1016/j.biopsych.2015.12.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Revised: 12/14/2015] [Accepted: 12/15/2015] [Indexed: 10/22/2022]
Abstract
The field of psychiatry is approaching a major inflection point. The basic science behind cognition, emotion, behavior, and social processes has been advancing rapidly in the past 20 years. However, clinical research supporting the classification system in psychiatry has not kept up with these scientific advances. To begin organizing the basic science of psychiatry in a comprehensive manner, we begin by selecting fragile X syndrome, a neurogenetic disease with cognitive-behavioral manifestations, to illustrate key concepts in an integrative, multidimensional model. Specifically, we describe key genetic and molecular mechanisms (e.g., gamma-aminobutyric acidergic dysfunction and metabotropic glutamate receptor 5-associated long-term depression) relevant to the pathophysiology of fragile X syndrome as well as neural correlates of cognitive-behavioral symptoms. We then describe what we have learned from fragile X syndrome that may be applicable to other psychiatric disorders. We conclude this review by discussing current and future opportunities in diagnosing and treating psychiatric diseases.
Collapse
Affiliation(s)
- Lawrence K. Fung
- Division of Child & Adolescent Psychiatry, Department of Psychiatry & Behavioral Sciences, Stanford University, Stanford, CA
| | - Allan L. Reiss
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry & Behavioral Sciences, Stanford University, Stanford, CA
| |
Collapse
|
30
|
Piracetam prevents memory deficit induced by postnatal propofol exposure in mice. Eur J Pharmacol 2016; 779:59-65. [DOI: 10.1016/j.ejphar.2016.03.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 02/22/2016] [Accepted: 03/04/2016] [Indexed: 11/18/2022]
|
31
|
Developmental DSP4 effects on cortical Arc expression. Neurosci Lett 2016; 618:89-93. [PMID: 26946107 DOI: 10.1016/j.neulet.2016.02.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/23/2016] [Accepted: 02/29/2016] [Indexed: 11/23/2022]
Abstract
Activity Regulated Cytoskeleton Associated Protein (Arc) is an immediate early gene that is critical to brain plasticity. In this study, norepinephrine's regulation of Arc expression was examined during different stages of postnatal development. Rats were injected with N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride (DSP-4), a selective noradrenergic neurotoxin, during preadolescence (PND 0 or 13), adolescence (PND 23 or 48) or adulthood (PND 60). After each DSP4 treatment, brains were harvested later in development and Arc mRNA levels analyzed with in situ hybridization. Rats lesioned with DSP4 during preadolescence showed no differences in Arc level compared to saline treated controls. In contrast, adolescence was a time of changing Arc mRNA response to DSP4. Rats lesioned during early adolescence showed Arc expression increases, while rats lesioned during late adolescence showed dramatic Arc expression decreases. Decreases in Arc level caused by late adolescent DSP4 were similar to those found in lesioned adults. These findings highlight a qualitatively different regulation of Arc expression by norepinephrine according to developmental stage, and indicate that mature regulation is not intact until late adolescence. These data point to important developmental differences in norepinephrine's regulation of brain plasticity. These differences may underlie contrasting psychotropic responses in children and adolescents compared to adults.
Collapse
|
32
|
Sweatt JD. Neural plasticity and behavior - sixty years of conceptual advances. J Neurochem 2016; 139 Suppl 2:179-199. [PMID: 26875778 DOI: 10.1111/jnc.13580] [Citation(s) in RCA: 186] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 01/19/2016] [Accepted: 02/09/2016] [Indexed: 02/06/2023]
Abstract
This brief review summarizes 60 years of conceptual advances that have demonstrated a role for active changes in neuronal connectivity as a controller of behavior and behavioral change. Seminal studies in the first phase of the six-decade span of this review firmly established the cellular basis of behavior - a concept that we take for granted now, but which was an open question at the time. Hebbian plasticity, including long-term potentiation and long-term depression, was then discovered as being important for local circuit refinement in the context of memory formation and behavioral change and stabilization in the mammalian central nervous system. Direct demonstration of plasticity of neuronal circuit function in vivo, for example, hippocampal neurons forming place cell firing patterns, extended this concept. However, additional neurophysiologic and computational studies demonstrated that circuit development and stabilization additionally relies on non-Hebbian, homoeostatic, forms of plasticity, such as synaptic scaling and control of membrane intrinsic properties. Activity-dependent neurodevelopment was found to be associated with cell-wide adjustments in post-synaptic receptor density, and found to occur in conjunction with synaptic pruning. Pioneering cellular neurophysiologic studies demonstrated the critical roles of transmembrane signal transduction, NMDA receptor regulation, regulation of neural membrane biophysical properties, and back-propagating action potential in critical time-dependent coincidence detection in behavior-modifying circuits. Concerning the molecular mechanisms underlying these processes, regulation of gene transcription was found to serve as a bridge between experience and behavioral change, closing the 'nature versus nurture' divide. Both active DNA (de)methylation and regulation of chromatin structure have been validated as crucial regulators of gene transcription during learning. The discovery of protein synthesis dependence on the acquisition of behavioral change was an influential discovery in the neurochemistry of behavioral modification. Higher order cognitive functions such as decision making and spatial and language learning were also discovered to hinge on neural plasticity mechanisms. The role of disruption of these processes in intellectual disabilities, memory disorders, and drug addiction has recently been clarified based on modern genetic techniques, including in the human. The area of neural plasticity and behavior has seen tremendous advances over the last six decades, with many of those advances being specifically in the neurochemistry domain. This review provides an overview of the progress in the area of neuroplasticity and behavior over the life-span of the Journal of Neurochemistry. To organize the broad literature base, the review collates progress into fifteen broad categories identified as 'conceptual advances', as viewed by the author. The fifteen areas are delineated in the figure above. This article is part of the 60th Anniversary special issue.
Collapse
Affiliation(s)
- J David Sweatt
- Department of Neurobiology, Evelyn F. McKnight Brain Institute and Civitan International Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA.
| |
Collapse
|
33
|
Essali N, Sanders J. Interdependent adrenergic receptor regulation of Arc and Zif268 mRNA in cerebral cortex. Neurosci Lett 2016; 612:38-42. [PMID: 26655475 PMCID: PMC4727989 DOI: 10.1016/j.neulet.2015.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 11/30/2015] [Accepted: 12/01/2015] [Indexed: 11/30/2022]
Abstract
Norepinephrine is a neurotransmitter that signals by stimulating the α1, α2 and β adrenergic receptor (AR). We determined the role of these receptors in regulating the immediate early genes, Activity Regulated Cytoskeleton Associated Protein (Arc) and Zif268 in the rat cerebral cortex. RX821002, an α2-AR antagonist, produced Arc and Zif268 elevations across cortical layers. Next we examined the effects of delivering RX821002 with an α1-AR antagonist, prazosin, and a β-AR antagonist, propranolol. RX821002 given with a prazosin and propranolol cocktail, or with each of these antagonists individually, decreased Arc and Zif268 to saline-treated control levels in most cortical layers. Arc and Zif268 levels were also similar to saline-treated control levels when rats were given a prazosin and propranolol cocktail alone, or when each of these antagonists were delivered individually. Taken together, these data reveal that α2-AR uniquely exert a tonic inibitory regulation of both Arc and Zif268 compared to α1 and β-AR. However, the ability of RX821002 to increase Arc and Zif268 is interdependent with α1 and β-AR signaling.
Collapse
Affiliation(s)
- Norah Essali
- College of Medicine, Texila American University, Georgetown, Guyana
| | - Jeff Sanders
- Department of Pharmacology and Experimental Neuroscience, 985800 Nebraska Medical Center, Omaha, NE 68198-5800, USA.
| |
Collapse
|
34
|
Morphological Differentiation Towards Neuronal Phenotype of SH-SY5Y Neuroblastoma Cells by Estradiol, Retinoic Acid and Cholesterol. Neurochem Res 2015; 41:731-47. [PMID: 26518675 PMCID: PMC4824837 DOI: 10.1007/s11064-015-1743-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Revised: 10/16/2015] [Accepted: 10/17/2015] [Indexed: 12/29/2022]
Abstract
Human SH-SY5Y neuroblastoma cells maintain their potential for differentiation and regression in culture conditions. The induction of differentiation could serve as a strategy to inhibit cell proliferation and tumor growth. Previous studies have shown that differentiation of SH-SY5Y cells can be induced by all-trans-retinoic-acid (RA) and cholesterol (CHOL). However, signaling pathways that lead to terminal differentiation of SH-SY5Y cells are still largely unknown. The goal of this study was to examine in the RA and CHOL treated SH-SY5Y cells the additive impacts of estradiol (E2) and brain-derived neurotrophic factor (BDNF) on cell morphology, cell population growth, synaptic vesicle recycling and presence of neurofilaments. The above features indicate a higher level of neuronal differentiation. Our data show that treatment for 10 days in vitro (DIV) with RA alone or when combined with E2 (RE) or CHOL (RC), but not when combined with BDNF (RB), significantly (p < 0.01) inhibited the cell population growth. Synaptic vesicle recycling, induced by high-K(+) depolarization, was significantly increased in all treatments where RA was included (RE, RC, RB, RCB), and when all agents were added together (RCBE). Specifically, our results show for the first time that E2 treatment can alone increase synaptic vesicle recycling in SH-SY5Y cells. This work contributes to the understanding of the ways to improve suppression of neuroblastoma cells' population growth by inducing maturation and differentiation.
Collapse
|
35
|
Abstract
The dentate gyrus (DG) plays a critical role in memory formation and maintenance. Fitting this specialized role, the DG has many unique characteristics. In addition to being one of the few places in which new neurons are continually added in adulthood, the region also shows a unique long-term sustained transcriptional response of the immediate-early gene Arc to sensory input. Although we know that adult-generated granule cells are reliably recruited into behaviorally-driven neuronal network, it remains unknown whether they display robust late-phase sustained transcription in response to activity like their developmentally-generated counterparts. Since this late-phase of transcription is required for enduring plasticity, knowing if sustained transcription appears as soon as these cells are incorporated provides information on their potential for plasticity. To address this question, adult F344 rats were injected with BrdU (50mg/kg/day for 5 days) and 4 weeks later explored a novel environment. Arc expression in both BrdU- and BrdU+ neurons was determined 0.5h, 1h, 2h, 6h, 8h, 12h, or 24h following this behavior. Recently-generated granule cells showed a robust sustained Arc expression following a discrete behavioral experience. These data provide information on a potential mechanism to sculpt the representations of events occurring within hours of each other to create uncorrelated representations of episodes despite a highly excitable population of neurons.
Collapse
Affiliation(s)
- Alicia Meconi
- Department of Psychology, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada
| | - Erika Lui
- Department of Psychology, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada
| | - Diano F Marrone
- Department of Psychology, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada; McKnight Brain Institute, University of Arizona, Tucson, AZ 85724, USA.
| |
Collapse
|
36
|
Bojovic O, Panja D, Bittins M, Bramham CR, Tjølsen A. Time course of immediate early gene protein expression in the spinal cord following conditioning stimulation of the sciatic nerve in rats. PLoS One 2015; 10:e0123604. [PMID: 25860146 PMCID: PMC4393234 DOI: 10.1371/journal.pone.0123604] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 02/20/2015] [Indexed: 12/20/2022] Open
Abstract
Long-term potentiation induced by conditioning electrical stimulation of afferent fibers is a widely studied form of synaptic plasticity in the brain and the spinal cord. In the spinal cord dorsal horn, long-term potentiation is induced by a series of high-frequency trains applied to primary afferent fibers. Conditioning stimulation (CS) of sciatic nerve primary afferent fibers also induces expression of immediate early gene proteins in the lumbar spinal cord. However, the time course of immediate early gene expression and the rostral-caudal distribution of expression in the spinal cord have not been systematically studied. Here, we examined the effects of sciatic nerve conditioning stimulation (10 stimulus trains, 0.5 ms stimuli, 7.2 mA, 100 Hz, train duration 2 s, 8 s intervals between trains) on cellular expression of immediate early genes, Arc, c-Fos and Zif268, in anesthetized rats. Immunohistochemical analysis was performed on sagittal sections obtained from Th13- L5 segments of the spinal cord at 1, 2, 3, 6 and 12 h post-CS. Strikingly, all immediate early genes exhibited a monophasic increase in expression with peak increases detected in dorsal horn neurons at 2 hours post-CS. Regional analysis showed peak increases at the location between the L3 and L4 spinal segments. Both Arc, c-Fos and Zif268 remained significantly elevated at 2 hours, followed by a sharp decrease in immediate early gene expression between 2 and 3 hours post-CS. Colocalization analysis performed at 2 hours post-CS showed that all c-Fos and Zif268 neurons were positive for Arc, while 30% and 43% of Arc positive neurons were positive for c-Fos and Zif268, respectively. The present study identifies the spinal cord level and time course of immediate early gene (IEGP) expression of relevance for analysis of IEGPs function in neuronal plasticity and nociception.
Collapse
Affiliation(s)
- Ognjen Bojovic
- Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway
- * E-mail:
| | - Debabrata Panja
- Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway
| | - Margarethe Bittins
- Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway
| | - Clive R. Bramham
- Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway
| | - Arne Tjølsen
- Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway
| |
Collapse
|
37
|
Hu SS, Mei L, Chen JY, Huang ZW, Wu H. Expression of immediate-early genes in the dorsal cochlear nucleus in salicylate-induced tinnitus. Eur Arch Otorhinolaryngol 2015; 273:325-32. [DOI: 10.1007/s00405-014-3479-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 12/25/2014] [Indexed: 02/08/2023]
|
38
|
Cao G, Harris KM. Augmenting saturated LTP by broadly spaced episodes of theta-burst stimulation in hippocampal area CA1 of adult rats and mice. J Neurophysiol 2014; 112:1916-24. [PMID: 25057146 DOI: 10.1152/jn.00297.2014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Hippocampal long-term potentiation (LTP) is a model system for studying cellular mechanisms of learning and memory. Recent interest in mechanisms underlying the advantage of spaced over massed learning has prompted investigation into the effects of distributed episodes of LTP induction. The amount of LTP induced in hippocampal area CA1 by one train (1T) of theta-burst stimulation (TBS) in young Sprague-Dawley rats was further enhanced by additional bouts of 1T given at 1-h intervals. However, in young Long-Evans (LE) rats, 1T did not initially saturate LTP. Instead, a stronger LTP induction paradigm using eight trains of TBS (8T) induced saturated LTP in hippocampal slices from both young and adult LE rats as well as adult mice. The saturated LTP induced by 8T could be augmented by another episode of 8T following an interval of at least 90 min. The success rate across animals and slices in augmenting LTP by an additional episode of 8T increased significantly with longer intervals between the first and last episodes, ranging from 0% at 30- and 60-min intervals to 13-66% at 90- to 180-min intervals to 90-100% at 240-min intervals. Augmentation above initially saturated LTP was blocked by the N-methyl-D-aspartate (NMDA) glutamate receptor antagonist D-2-amino-5-phosphonovaleric acid (D-APV). These findings suggest that the strength of induction and interval between episodes of TBS, as well as the strain and age of the animal, are important components in the augmentation of LTP.
Collapse
Affiliation(s)
- Guan Cao
- The Center for Learning and Memory, University of Texas at Austin, Austin, Texas
| | - Kristen M Harris
- The Center for Learning and Memory, University of Texas at Austin, Austin, Texas
| |
Collapse
|
39
|
Thomas MG, Pascual ML, Maschi D, Luchelli L, Boccaccio GL. Synaptic control of local translation: the plot thickens with new characters. Cell Mol Life Sci 2014; 71:2219-39. [PMID: 24212248 PMCID: PMC11113725 DOI: 10.1007/s00018-013-1506-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2013] [Revised: 10/11/2013] [Accepted: 10/21/2013] [Indexed: 12/18/2022]
Abstract
The production of proteins from mRNAs localized at the synapse ultimately controls the strength of synaptic transmission, thereby affecting behavior and cognitive functions. The regulated transcription, processing, and transport of mRNAs provide dynamic control of the dendritic transcriptome, which includes thousands of messengers encoding multiple cellular functions. Translation is locally modulated by synaptic activity through a complex network of RNA-binding proteins (RBPs) and various types of non-coding RNAs (ncRNAs) including BC-RNAs, microRNAs, piwi-interacting RNAs, and small interference RNAs. The RBPs FMRP and CPEB play a well-established role in synaptic translation, and additional regulatory factors are emerging. The mRNA repressors Smaug, Nanos, and Pumilio define a novel pathway for local translational control that affects dendritic branching and spines in both flies and mammals. Recent findings support a role for processing bodies and related synaptic mRNA-silencing foci (SyAS-foci) in the modulation of synaptic plasticity and memory formation. The SyAS-foci respond to different stimuli with changes in their integrity thus enabling regulated mRNA release followed by translation. CPEB, Pumilio, TDP-43, and FUS/TLS form multimers through low-complexity regions related to prion domains or polyQ expansions. The oligomerization of these repressor RBPs is mechanistically linked to the aggregation of abnormal proteins commonly associated with neurodegeneration. Here, we summarize the current knowledge on how specificity in mRNA translation is achieved through the concerted action of multiple pathways that involve regulatory ncRNAs and RBPs, the modification of translation factors, and mRNA-silencing foci dynamics.
Collapse
Affiliation(s)
- María Gabriela Thomas
- Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
- IIBBA-CONICET, C1405BWE Buenos Aires, Argentina
| | - Malena Lucía Pascual
- Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
- IIBBA-CONICET, C1405BWE Buenos Aires, Argentina
- Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
| | - Darío Maschi
- Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
- Present Address: Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO USA
| | - Luciana Luchelli
- Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
- IIBBA-CONICET, C1405BWE Buenos Aires, Argentina
| | - Graciela Lidia Boccaccio
- Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
- IIBBA-CONICET, C1405BWE Buenos Aires, Argentina
- Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
| |
Collapse
|
40
|
Williamson LL, Bilbo SD. Neonatal infection modulates behavioral flexibility and hippocampal activation on a Morris Water Maze task. Physiol Behav 2014; 129:152-9. [PMID: 24576680 PMCID: PMC4005787 DOI: 10.1016/j.physbeh.2014.02.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 10/29/2013] [Accepted: 02/12/2014] [Indexed: 10/25/2022]
Abstract
Neonatal infection has enduring effects on the brain, both at the cellular and behavioral levels. We determined the effects of peripheral infection with Escherichia coli at postnatal day (P) 4 in rats on a water maze task in adulthood, and assessed neuronal activation in the dentate gyrus (DG) following the memory test. Rats were trained and tested on one of 3 distinct water maze task paradigms: 1) minimal training (18 trials/3days), 2) extended training (50 trials/10days) or 3) reversal training (extended training followed by 30 trials/3days with a new platform location). Following a 48h memory test, brains were harvested to assess neuronal activation using activity-regulated cytoskeleton-associated (Arc) protein in the DG. Following minimal training, rats treated neonatally with E. coli had improved performance and paradoxically reduced Arc expression during the memory test compared to control rats treated with PBS early in life. However, neonatally-infected rats did not differ from control rats in behavior or neuronal activation during the memory test following extended training. Furthermore, rats treated neonatally with E. coli were significantly impaired during the 48h memory test for a reversal platform location, unlike controls. Specifically, whereas neonatally-infected rats were able to acquire the new location at the same rate as controls, they spent significantly less time in the target quadrant for the reversal platform during a memory test. However, neonatally-infected and control rats had similar levels of Arc expression following the 48h memory test for reversal. Together, these data indicate that neonatal infection may improve the rate of acquisition on hippocampal-dependent tasks while impairing flexibility on the same tasks; in addition, network activation in the DG during learning may be predictive of future cognitive flexibility on a hippocampal-dependent task.
Collapse
Affiliation(s)
- Lauren L Williamson
- Department of Psychology & Neuroscience, Duke University, Durham, NC 27708, United States.
| | - Staci D Bilbo
- Department of Psychology & Neuroscience, Duke University, Durham, NC 27708, United States
| |
Collapse
|
41
|
Ravinder S, Burghardt NS, Brodsky R, Bauer EP, Chattarji S. A role for the extended amygdala in the fear-enhancing effects of acute selective serotonin reuptake inhibitor treatment. Transl Psychiatry 2013; 3:e209. [PMID: 23321806 PMCID: PMC3566718 DOI: 10.1038/tp.2012.137] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Selective serotonin reuptake inhibitors (SSRIs) are reported to exacerbate symptoms of anxiety when treatment is initiated. These clinical findings have been extended to animal models wherein SSRIs also potentiate anxiety and fear learning, which depend on the amygdala. Yet, little is known about the role of specific amygdalar circuits in these acute effects of SSRIs. Here, we first confirmed that a single injection of fluoxetine 1 h before auditory fear conditioning potentiated fear memory in rats. To probe the neural substrates underlying this enhancement, we analyzed the expression patterns of the immediate early gene, Arc (activity-regulated cytoskeleton-associated protein). Consistent with previous reports, fear conditioning induced Arc protein expression in the lateral and basal amygdala. However, this was not enhanced further by pre-treatment with fluoxetine. Instead, fluoxetine significantly enhanced expression of Arc in the central amygdala (CeA) and the bed nucleus of the stria terminalis (BNST). Next, we tested whether direct targeted infusions of fluoxetine into the CeA, or BNST, leads to the same fear-potentiating effect. Strikingly, direct infusion of fluoxetine into the BNST, but not the CeA, was sufficient to enhance fear memory. Moreover, this behavioral effect was also accompanied by robust Arc expression in the CeA, similar to the systemic injection. Our results identify a novel role for the BNST in the acute fear-enhancing effects of SSRIs. These findings highlight the need to look beyond the traditional focus on input nuclei of the amygdala and add to accumulating evidence implicating these microcircuits in gating fear and anxiety.
Collapse
Affiliation(s)
- S Ravinder
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India
| | - N S Burghardt
- Departments of Neuroscience, Psychiatry & Pharmacology, Columbia University, New York, NY, USA
| | - R Brodsky
- Biology Department, Barnard College, Columbia University, New York, NY, USA
| | - E P Bauer
- Biology Department, Barnard College, Columbia University, New York, NY, USA
| | - S Chattarji
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India,National Centre for Biological Sciences, GKVK Campus, Bellary Road, Bangalore 560065, India. E-mail:
| |
Collapse
|
42
|
Figge DA, Rahman I, Dougherty PJ, Rademacher DJ. Retrieval of contextual memories increases activity-regulated cytoskeleton-associated protein in the amygdala and hippocampus. Brain Struct Funct 2012; 218:1177-96. [PMID: 22945419 DOI: 10.1007/s00429-012-0453-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 08/17/2012] [Indexed: 01/16/2023]
Abstract
Activity-regulated cytoskeleton-associated protein (Arc) integrates information from multiple intracellular signaling cascades and, in turn, regulates cytoskeletal proteins involved in structural synaptic modifications. The purposes of the present study were: (1) to determine if the retrieval of contextual memories would induce Arc in hippocampal and amygdalar neurons; (2) use unbiased stereology at the ultrastructural level to quantify synapses contacting Arc-labeled (Arc+) and unlabeled (Arc-) postsynaptic structures in brain regions in which the amount of Arc integrated density (ID) correlated strongly with the degree of amphetamine conditioned place preference (AMPH CPP). The retrieval of contextual memories increased the Arc ID in the dentate gyrus, cornu ammonis (CA)1, and CA3 fields of the hippocampus and the basolateral, lateral, and central nuclei of the amygdala but not the primary auditory cortex, a control region. Stereological quantification of Arc+ and Arc- synapses in the basolateral nucleus of the amygdala (BLA) was undertaken because the strongest relationship between the amount of Arc ID and AMPH CPP was observed in the BLA. The retrieval of contextual memories increased the number and density of asymmetric (presumed excitatory) synapses contacting Arc+ spines and dendrites of BLA neurons, symmetric (presumed inhibitory or modulatory) synapses contacting Arc+ dendrites of BLA neurons, and multisynaptic boutons contacting Arc+ postsynaptic structures. Thus, the retrieval of contextual memories increases Arc in the amygdala and hippocampus, an effect that could be important for approach behavior to a drug-associated context.
Collapse
Affiliation(s)
- David A Figge
- Department of Cellular and Molecular Pharmacology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
| | | | | | | |
Collapse
|
43
|
Chang YF, Chou HJ, Yen YC, Chang HW, Hong YR, Huang HW, Tseng CN. Agrin induces association of Chrna1 mRNA and nicotinic acetylcholine receptor in C2C12 myotubes. FEBS Lett 2012; 586:3111-6. [PMID: 22884571 DOI: 10.1016/j.febslet.2012.07.068] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 07/05/2012] [Accepted: 07/20/2012] [Indexed: 11/30/2022]
Abstract
In the mammalian central nervous system transcripts of certain synaptic components are localized near the synapse, allowing for rapid regulation of protein levels. Here we test whether an mRNA localization mechanism also exists in the postsynaptic specialization induced by agrin in C2C12 myotubes. RT-PCR showed that Chrna1 was co-purified with nicotinic acetylcholine receptor (AChR) isolated by affinity column or by ultracentrifugation. In addition, Stau1 was found to interact with Chrna1 mRNA, and knocking down of Stau1 by RNAi resulted in defective AChR clustering. These results suggest that mRNA localization also participates in the formation of mammalian neuromuscular junction (NMJ).
Collapse
Affiliation(s)
- Yung-Fu Chang
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung City 807, Taiwan
| | | | | | | | | | | | | |
Collapse
|
44
|
Consequences of inhibiting amyloid precursor protein processing enzymes on synaptic function and plasticity. Neural Plast 2012; 2012:272374. [PMID: 22792491 PMCID: PMC3390164 DOI: 10.1155/2012/272374] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 04/22/2012] [Indexed: 12/21/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease, one of whose major pathological hallmarks is the accumulation of amyloid plaques comprised of aggregated β-amyloid (Aβ) peptides. It is now recognized that soluble Aβ oligomers may lead to synaptic dysfunctions early in AD pathology preceding plaque deposition. Aβ is produced by a sequential cleavage of amyloid precursor protein (APP) by the activity of β- and γ-secretases, which have been identified as major candidate therapeutic targets of AD. This paper focuses on how Aβ alters synaptic function and the functional consequences of inhibiting the activity of the two secretases responsible for Aβ generation. Abnormalities in synaptic function resulting from the absence or inhibition of the Aβ-producing enzymes suggest that Aβ itself may have normal physiological functions which are disrupted by abnormal accumulation of Aβ during AD pathology. This interpretation suggests that AD therapeutics targeting the β- and γ-secretases should be developed to restore normal levels of Aβ or combined with measures to circumvent the associated synaptic dysfunction(s) in order to have minimal impact on normal synaptic function.
Collapse
|
45
|
Abstract
RNA transport granules deliver translationally repressed mRNAs to synaptic sites in dendrites, where synaptic activity promotes their localized translation. Although the identity of many proteins that make up the neuronal granules is known, the stoichiometry of their core component, the mRNA, is poorly understood. By imaging nine different dendritically localized mRNA species with single-molecule sensitivity and subdiffraction-limit resolution in cultured hippocampal neurons, we show that two molecules of the same or different mRNA species do not assemble in common structures. Even mRNA species with a common dendritic localization element, the sequence that is believed to mediate the incorporation of these mRNAs into common complexes, do not colocalize. These results suggest that mRNA molecules traffic to the distal reaches of dendrites singly and independently of others, a model that permits a finer control of mRNA content within a synapse for synaptic plasticity.
Collapse
|
46
|
Baez MV, Luchelli L, Maschi D, Habif M, Pascual M, Thomas MG, Boccaccio GL. Smaug1 mRNA-silencing foci respond to NMDA and modulate synapse formation. ACTA ACUST UNITED AC 2012; 195:1141-57. [PMID: 22201125 PMCID: PMC3246892 DOI: 10.1083/jcb.201108159] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
S-foci, the first reported mRNA-silencing foci specific to neurons, may control local mRNA translation in response to NMDA receptor stimulation and synaptic plasticity. Mammalian Smaug1/Samd4A is a translational repressor. Here we show that Smaug1 forms mRNA-silencing foci located at postsynapses of hippocampal neurons. These structures, which we have named S-foci, are distinct from P-bodies, stress granules, or other neuronal RNA granules hitherto described, and are the first described mRNA-silencing foci specific to neurons. RNA binding was not required for aggregation, which indicates that S-foci formation is not a consequence of mRNA silencing. N-methyl-d-aspartic acid (NMDA) receptor stimulation provoked a rapid and reversible disassembly of S-foci, transiently releasing transcripts (the CaMKIIα mRNA among others) to allow their translation. Simultaneously, NMDA triggered global translational silencing, which suggests the specific activation of Smaug1-repressed transcripts. Smaug1 is expressed during synaptogenesis, and Smaug1 knockdown affected the number and size of synapses, and also provoked an impaired response to repetitive depolarizing stimuli, as indicated by a reduced induction of Arc/Arg3.1. Our results suggest that S-foci control local translation, specifically responding to NMDA receptor stimulation and affecting synaptic plasticity.
Collapse
|
47
|
Santoro MR, Bray SM, Warren ST. Molecular mechanisms of fragile X syndrome: a twenty-year perspective. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2011; 7:219-45. [PMID: 22017584 DOI: 10.1146/annurev-pathol-011811-132457] [Citation(s) in RCA: 377] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Fragile X syndrome (FXS) is a common form of inherited intellectual disability and is one of the leading known causes of autism. The mutation responsible for FXS is a large expansion of the trinucleotide CGG repeat in the 5' untranslated region of the X-linked gene FMR1. This expansion leads to DNA methylation of FMR1 and to transcriptional silencing, which results in the absence of the gene product, FMRP, a selective messenger RNA (mRNA)-binding protein that regulates the translation of a subset of dendritic mRNAs. FMRP is critical for mGluR (metabotropic glutamate receptor)-dependent long-term depression, as well as for other forms of synaptic plasticity; its absence causes excessive and persistent protein synthesis in postsynaptic dendrites and dysregulated synaptic function. Studies continue to refine our understanding of FMRP's role in synaptic plasticity and to uncover new functions of this protein, which have illuminated therapeutic approaches for FXS.
Collapse
Affiliation(s)
- Michael R Santoro
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
| | | | | |
Collapse
|
48
|
Korb E, Finkbeiner S. Arc in synaptic plasticity: from gene to behavior. Trends Neurosci 2011; 34:591-8. [PMID: 21963089 DOI: 10.1016/j.tins.2011.08.007] [Citation(s) in RCA: 257] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2011] [Revised: 08/26/2011] [Accepted: 08/30/2011] [Indexed: 10/17/2022]
Abstract
The activity-regulated cytoskeletal (Arc) gene encodes a protein that is critical for memory consolidation. Arc is one of the most tightly regulated molecules known: neuronal activity controls Arc mRNA induction, trafficking and accumulation, and Arc protein production, localization and stability. Arc regulates synaptic strength through multiple mechanisms and is involved in essentially every known form of synaptic plasticity. It also mediates memory formation and is implicated in multiple neurological diseases. In this review, we will discuss how Arc is regulated and used as a tool to study neuronal activity. We will also attempt to clarify how its molecular functions correspond to its requirement in various forms of plasticity, discuss Arc's role in behavior and disease, and highlight critical unresolved questions.
Collapse
Affiliation(s)
- Erica Korb
- Gladstone Institute of Neurological Disease, San Francisco, CA, USA
| | | |
Collapse
|
49
|
Ena S, de Kerchove d'Exaerde A, Schiffmann SN. Unraveling the differential functions and regulation of striatal neuron sub-populations in motor control, reward, and motivational processes. Front Behav Neurosci 2011; 5:47. [PMID: 21847377 PMCID: PMC3148764 DOI: 10.3389/fnbeh.2011.00047] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 07/18/2011] [Indexed: 12/15/2022] Open
Abstract
The striatum, the major input structure of the basal ganglia, is critically involved in motor control and learning of habits and skills, and is also involved in motivational and reward processes. The dorsal striatum, caudate–putamen, is primarily implicated in motor functions whereas the ventral striatum, the nucleus accumbens, is essential for motivation and drug reinforcement. Severe basal ganglia dysfunction occurs in movement disorders as Parkinson's and Huntington's disease, and in psychiatric disorders such as schizophrenia and drug addiction. The striatum is essentially composed of GABAergic medium-sized spiny neurons (MSNs) that are output neurons giving rise to the so-called direct and indirect pathways and are targets of the cerebral cortex and mesencephalic dopaminergic neurons. Although the involvement of striatal sub-areas in motor control and motivation has been thoroughly characterized, major issues remained concerning the specific and respective functions of the two MSNs sub-populations, D2R-striatopallidal (dopamine D2 receptor-positive) and D1R-striatonigral (dopamine D1 receptor-positive) neurons, as well as their specific regulation. Here, we review recent advances that gave new insight in the understanding of the differential roles of striatopallidal and striatonigral neurons in the basal ganglia circuit. We discuss innovative techniques developed in the last decade which allowed a much precise evaluation of molecular pathways implicated in motivational processes and functional roles of striatopallidal and striatonigral neurons in motor control and in the establishment of reward-associated behavior.
Collapse
Affiliation(s)
- Sabrina Ena
- Laboratory of Neurophysiology, School of Medicine, Université Libre de Bruxelles Brussels, Belgium
| | | | | |
Collapse
|
50
|
Suppression of activity-regulated cytoskeleton-associated gene expression in the dorsal striatum attenuates extinction of cocaine-seeking. Int J Neuropsychopharmacol 2011; 14:784-95. [PMID: 20942997 PMCID: PMC3120104 DOI: 10.1017/s1461145710001173] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The caudate putamen (CPu) has been implicated in habit learning and neuroadaptive changes that mediate the compulsive nature of drug-seeking following chronic cocaine self-administration. Re-exposure to an operant chamber previously associated with cocaine, but not yoked-saline, increases activity-regulated cytoskeleton-associated (Arc) gene mRNA expression within the dorsolateral (dl) CPu following prolonged abstinence. In this study, we tested the hypothesis that antisense gene knockdown of Arc within the dlCPu would alter cocaine-seeking. Initial studies showed that a single infusion of Arc antisense oligodeoxynucleotide (ODN) into the dlCPu significantly attenuated the induction of Arc mRNA and Arc protein by a single cocaine exposure (20 mg/kg i.p.) compared to scrambled-ODN-infused controls. In cocaine self-administering rats, infusion of Arc antisense ODN into the dlCPu 3 h prior to a test of context-driven drug-seeking significantly attenuated Arc protein induction, but failed to alter responding during testing, suggesting striatal Arc does not facilitate context-induced drug-seeking following prolonged abstinence. However, Arc antisense ODN infusion blunted the decrease in responding during subsequent 1-h extinction tests 24 and 48 h later. Following re-exposure to a cocaine-paired context, surface expression of the AMPA-type glutamate receptor GluR1 was significantly reduced whereas GluR2 was significantly increased in the dlCPu, independent of Arc antisense ODN infusion. Together, these findings indicate an important role for Arc in neuroadaptations within brain regions responsible for drug-seeking after abstinence and direct attention to changes occurring within striatal circuitry that are necessary to break down the habitual behaviour that leads to relapse.
Collapse
|