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Reduced hippocampal inhibition and enhanced autism-epilepsy comorbidity in mice lacking neuropilin 2. Transl Psychiatry 2021; 11:537. [PMID: 34663783 PMCID: PMC8523694 DOI: 10.1038/s41398-021-01655-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 08/18/2021] [Accepted: 09/17/2021] [Indexed: 12/19/2022] Open
Abstract
The neuropilin receptors and their secreted semaphorin ligands play key roles in brain circuit development by regulating numerous crucial neuronal processes, including the maturation of synapses and migration of GABAergic interneurons. Consistent with its developmental roles, the neuropilin 2 (Nrp2) locus contains polymorphisms in patients with autism spectrum disorder (ASD). Nrp2-deficient mice show autism-like behavioral deficits and propensity to develop seizures. In order to determine the pathophysiology in Nrp2 deficiency, we examined the hippocampal numbers of interneuron subtypes and inhibitory regulation of hippocampal CA1 pyramidal neurons in mice lacking one or both copies of Nrp2. Immunostaining for interneuron subtypes revealed that Nrp2-/- mice have a reduced number of parvalbumin, somatostatin, and neuropeptide Y cells, mainly in CA1. Whole-cell recordings identified reduced firing and hyperpolarized shift in resting membrane potential in CA1 pyramidal neurons from Nrp2+/- and Nrp2-/- mice compared to age-matched wild-type controls indicating decrease in intrinsic excitability. Simultaneously, the frequency and amplitude of spontaneous inhibitory postsynaptic currents (sIPSCs) are reduced in Nrp2-deficient mice. A convulsive dose of kainic acid evoked electrographic and behavioral seizures with significantly shorter latency, longer duration, and higher severity in Nrp2-/- compared to Nrp2+/+ animals. Finally, Nrp2+/- and Nrp2-/- but not Nrp2+/+, mice have impaired cognitive flexibility demonstrated by reward-based reversal learning, a task associated with hippocampal circuit function. Together these data demonstrate a broad reduction in interneuron subtypes and compromised inhibition in CA1 of Nrp2-/- mice, which could contribute to the heightened seizure susceptibility and behavioral deficits consistent with an ASD/epilepsy phenotype.
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A Functional Role for the Epigenetic Regulator ING1 in Activity-induced Gene Expression in Primary Cortical Neurons. Neuroscience 2017; 369:248-260. [PMID: 29158107 DOI: 10.1016/j.neuroscience.2017.11.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 11/09/2017] [Accepted: 11/11/2017] [Indexed: 12/19/2022]
Abstract
Epigenetic regulation of activity-induced gene expression involves multiple levels of molecular interaction, including histone and DNA modifications, as well as mechanisms of DNA repair. Here we demonstrate that the genome-wide deposition of inhibitor of growth family member 1 (ING1), which is a central epigenetic regulatory protein, is dynamically regulated in response to activity in primary cortical neurons. ING1 knockdown leads to decreased expression of genes related to synaptic plasticity, including the regulatory subunit of calcineurin, Ppp3r1. In addition, ING1 binding at a site upstream of the transcription start site (TSS) of Ppp3r1 depends on yet another group of neuroepigenetic regulatory proteins, the Piwi-like family, which are also involved in DNA repair. These findings provide new insight into a novel mode of activity-induced gene expression, which involves the interaction between different epigenetic regulatory mechanisms traditionally associated with gene repression and DNA repair.
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Zhao L, Chen T, Wang C, Li G, Zhi W, Yin J, Wan Q, Chen L. Atorvastatin in improvement of cognitive impairments caused by amyloid β in mice: involvement of inflammatory reaction. BMC Neurol 2016; 16:18. [PMID: 26846170 PMCID: PMC4743318 DOI: 10.1186/s12883-016-0533-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 01/16/2016] [Indexed: 11/23/2022] Open
Abstract
Background The production of inflammatory cytokines resulting from amyloid β (Aβ) is associated with the initiation of Alzheimer’s disease (AD). Atorvastatin (ATV) has been reported to improve AD, however, it is unclear how the anti-inflammatory mechanism is linked with its protection against the impairment of spatial cognitive function in AD. The present study was designed to explore what mechanism was possibly involved in the anti-inflammatory pathway in regard to the ATV treatment of AD. Methods We used an AD model induced by the administration of Aβ25–35 in male C57BL/6 mice and an in vitro culture system to study the protective effects of ATV on the spatial cognitive deficits, hippocampal long-term potentiation (LTP) impairment and inflammatory reaction. Results The intragastric administration of ATV (5 mg/kg) in Aβ25–35-treated mice significantly ameliorated the spatial cognitive deficits and prevented the LTP impairment in hippocampal CA1. The increased Iba-1 positive cells and inflammatory components in the hippocampus were reduced after the ATV treatment. The anti-inflammatory and LTP protection of ATV were abolished using the replenishment of farnesyl pyrophosphate by the administration of farnesol (FOH). The hippocampal slices culture showed Aβ25–35-induced neurotoxicity in the absence of the presence of ATV. Treatment with ATV (0.5, 1, 2.5 μmol/L) dose-dependently prevented the cell damage in hippocampus induced by Aβ25–35. Conclusion The administration of ATV ameliorated the cognitive deficits, depressed the inflammatory responses, improved the LTP impairment, and prevents Aβ25-35-induced neurotoxicity in cultured hippocampal neurons. These protective functions of ATV involved the pathway of reducing farnesyl pyrophosphate (FPP).
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Affiliation(s)
- Liandong Zhao
- Department of Neurology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu, 210029, China.,Department of Neurology, The Second Hospital of Huaian, Huaian, Jiangsu, 223002, China
| | - Tingting Chen
- Department of Physiology, Nanjing Medical University, Nanjing, 210029, China
| | - Chonghui Wang
- Department of Physiology, Nanjing Medical University, Nanjing, 210029, China
| | - Guoxi Li
- Department of Physiology, Nanjing Medical University, Nanjing, 210029, China
| | - Wenhui Zhi
- Department of Physiology, Nanjing Medical University, Nanjing, 210029, China
| | - Jun Yin
- Department of Physiology, Nanjing Medical University, Nanjing, 210029, China
| | - Qi Wan
- Department of Neurology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu, 210029, China.
| | - Ling Chen
- Department of Physiology, Nanjing Medical University, Nanjing, 210029, China. .,Laboratory of Reproductive Medicine, Department of Physiology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, China.
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Ellegood J, Nakai N, Nakatani J, Henkelman M, Takumi T, Lerch J. Neuroanatomical Phenotypes Are Consistent With Autism-Like Behavioral Phenotypes in the 15q11-13 Duplication Mouse Model. Autism Res 2015; 8:545-55. [PMID: 25755142 DOI: 10.1002/aur.1469] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 02/04/2015] [Indexed: 11/07/2022]
Abstract
Paternally and maternally inherited deletions and duplications of human chromosome 15q11-13 are relatively common in the human population. Furthermore, duplications in the 15q region are often associated with autism. Both maternal and paternal interstitial 15q11-13 duplication mouse models have been previously created, where several behavioral differences were found in the paternal duplication (patDp/+) mouse but not in the maternal duplication (matDp/+). These included decreased sociability, behavioral inflexibility, abnormal ultrasonic vocalizations, decreased spontaneous activity, and increased anxiety. Similarly, in the current study, we found several anatomical differences in the patDp/+ mice that were not seen in the matDp/+ mice. Regional differences that are evident only in the paternal duplication are a smaller dentate gyrus and smaller medial striatum. These differences may be responsible for the behavioral inflexibility. Furthermore, a smaller dorsal raphe nucleus could be responsible for the reported serotonin defects. This study highlights consistency that can be found between behavioral and anatomical phenotyping.
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Affiliation(s)
- Jacob Ellegood
- Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario Canada (J.E., R.M.H., J.L.)
| | - Nobuhiro Nakai
- RIKEN Brain Science Institute, Wako, Saiama, Japan (N.N., T.T.)
| | - Jin Nakatani
- Shiga University of Medical Science, Ohtsu, Shiga, Japan (J.N.)
| | - Mark Henkelman
- Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario Canada (J.E., R.M.H., J.L.)
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada (R.M.H., J.L.)
| | - Toru Takumi
- RIKEN Brain Science Institute, Wako, Saiama, Japan (N.N., T.T.)
- JST, CREST(T.T.)
| | - Jason Lerch
- Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario Canada (J.E., R.M.H., J.L.)
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada (R.M.H., J.L.)
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Transiently increasing cAMP levels selectively in hippocampal excitatory neurons during sleep deprivation prevents memory deficits caused by sleep loss. J Neurosci 2015; 34:15715-21. [PMID: 25411499 DOI: 10.1523/jneurosci.2403-14.2014] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The hippocampus is particularly sensitive to sleep loss. Although previous work has indicated that sleep deprivation impairs hippocampal cAMP signaling, it remains to be determined whether the cognitive deficits associated with sleep deprivation are caused by attenuated cAMP signaling in the hippocampus. Further, it is unclear which cell types are responsible for the memory impairments associated with sleep deprivation. Transgenic approaches lack the spatial resolution to manipulate specific signaling pathways selectively in the hippocampus, while pharmacological strategies are limited in terms of cell-type specificity. Therefore, we used a pharmacogenetic approach based on a virus-mediated expression of a Gαs-coupled Drosophila octopamine receptor selectively in mouse hippocampal excitatory neurons in vivo. With this approach, a systemic injection with the receptor ligand octopamine leads to increased cAMP levels in this specific set of hippocampal neurons. We assessed whether transiently increasing cAMP levels during sleep deprivation prevents memory consolidation deficits associated with sleep loss in an object-location task. Five hours of total sleep deprivation directly following training impaired the formation of object-location memories. Transiently increasing cAMP levels in hippocampal neurons during the course of sleep deprivation prevented these memory consolidation deficits. These findings demonstrate that attenuated cAMP signaling in hippocampal excitatory neurons is a critical component underlying the memory deficits in hippocampus-dependent learning tasks associated with sleep deprivation.
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de la Fuente V, Federman N, Fustiñana MS, Zalcman G, Romano A. Calcineurin phosphatase as a negative regulator of fear memory in hippocampus: control on nuclear factor-κB signaling in consolidation and reconsolidation. Hippocampus 2014; 24:1549-61. [PMID: 25043904 DOI: 10.1002/hipo.22334] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 07/07/2014] [Accepted: 07/14/2014] [Indexed: 12/27/2022]
Abstract
Protein phosphatases are important regulators of neural plasticity and memory. Some studies support that the Ca(2+) /calmodulin-dependent phosphatase calcineurin (CaN) is, on the one hand, a negative regulator of memory formation and, on the other hand, a positive regulator of memory extinction and reversal learning. However, the signaling mechanisms by which CaN exerts its action in such processes are not well understood. Previous findings support that CaN negatively regulate the nuclear factor kappaB (NF-κB) signaling pathway during extinction. Here, we have studied the role of CaN in contextual fear memory consolidation and reconsolidation in the hippocampus. We investigated the CaN control on the NF-κB signaling pathway, a key mechanism that regulates gene expression in memory processes. We found that post-training intrahippocampal administration of the CaN inhibitor FK506 enhanced memory retention one day but not two weeks after training. Accordingly, the inhibition of CaN by FK506 increased NF-κB activity in dorsal hippocampus. The administration of the NF-κB signaling pathway inhibitor sulfasalazine (SSZ) impeded the enhancing effect of FK506. In line with our findings in consolidation, FK506 administration before memory reactivation enhanced memory reconsolidation when tested one day after re-exposure to the training context. Strikingly, memory was also enhanced two weeks after training, suggesting that reinforcement during reconsolidation is more persistent than during consolidation. The coadministration of SSZ and FK506 blocked the enhancement effect in reconsolidation, suggesting that this facilitation is also dependent on the NF-κB signaling pathway. In summary, our results support a novel mechanism by which memory formation and reprocessing can be controlled by CaN regulation on NF-κB activity.
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Affiliation(s)
- Verónica de la Fuente
- Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina; Instituto de Fisiología, Biología Molecular y Neurociencias, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
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Hovens IB, Schoemaker RG, van der Zee EA, Heineman E, Nyakas C, van Leeuwen BL. Surgery-induced behavioral changes in aged rats. Exp Gerontol 2013; 48:1204-11. [PMID: 23916881 DOI: 10.1016/j.exger.2013.07.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 07/09/2013] [Accepted: 07/23/2013] [Indexed: 11/26/2022]
Abstract
Elderly patients may experience impairments in cognition or mood following surgery. To study the development and underlying mechanisms of these postoperative behavioral changes, young (3 months) and aged (18-20 months) male rats were subjected to abdominal surgery followed by behavioral testing during a period of 6 weeks. Microglia activation (IBA-1) and neurogenesis (DCX) were immunohistochemically determined. In separate experiments, the effects of anesthesia and the cytokine response (IL-6) following surgery were evaluated. Increased age was associated with changes in affective behavior, decreased cognitive flexibility and increased microglia activation as well as increased weight loss and plasma IL-6 following surgery. No effects of surgery on cognition were observed at either age. However, aged rats displayed long-term changes in affective behavior and had increased microgliosis in the CA1 hippocampal region following surgery. Microglia activation following surgery was positively correlated to parameters of behavior and spatial learning. These findings support the hypothesis that elderly patients have an increased behavioral and (neuro)inflammatory response to surgery and these factors may be related.
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Affiliation(s)
- Iris B Hovens
- Department of Molecular Neurobiology, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands.
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Gravin orchestrates protein kinase A and β2-adrenergic receptor signaling critical for synaptic plasticity and memory. J Neurosci 2013; 32:18137-49. [PMID: 23238728 DOI: 10.1523/jneurosci.3612-12.2012] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A kinase-anchoring proteins (AKAPs) organize compartmentalized pools of protein kinase A (PKA) to enable localized signaling events within neurons. However, it is unclear which of the many expressed AKAPs in neurons target PKA to signaling complexes important for long-lasting forms of synaptic plasticity and memory storage. In the forebrain, the anchoring protein gravin recruits a signaling complex containing PKA, PKC, calmodulin, and PDE4D (phosphodiesterase 4D) to the β2-adrenergic receptor. Here, we show that mice lacking the α-isoform of gravin have deficits in PKA-dependent long-lasting forms of hippocampal synaptic plasticity including β2-adrenergic receptor-mediated plasticity, and selective impairments of long-term memory storage. Furthermore, both hippocampal β2-adrenergic receptor phosphorylation by PKA, and learning-induced activation of ERK in the CA1 region of the hippocampus are attenuated in mice lacking gravin-α. We conclude that gravin compartmentalizes a significant pool of PKA that regulates learning-induced β2-adrenergic receptor signaling and ERK activation in the hippocampus in vivo, thereby organizing molecular interactions between glutamatergic and noradrenergic signaling pathways for long-lasting synaptic plasticity, and memory storage.
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Baumgärtel K, Mansuy IM. Neural functions of calcineurin in synaptic plasticity and memory. Learn Mem 2012; 19:375-84. [PMID: 22904368 DOI: 10.1101/lm.027201.112] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Major brain functions depend on neuronal processes that favor the plasticity of neuronal circuits while at the same time maintaining their stability. The mechanisms that regulate brain plasticity are complex and engage multiple cascades of molecular components that modulate synaptic efficacy. Protein kinases (PKs) and phosphatases (PPs) are among the most important of these components that act as positive and negative regulators of neuronal signaling and plasticity, respectively. In these cascades, the PP protein phosphatase 2B or calcineurin (CaN) is of particular interest because it is the only Ca(2+)-activated PP in the brain and a major regulator of key proteins essential for synaptic transmission and neuronal excitability. This review describes the primary properties of CaN and illustrates its functions and modes of action by focusing on several representative targets, in particular glutamate receptors, striatal enriched protein phosphatase (STEP), and neuromodulin (GAP43), and their functional significance for synaptic plasticity and memory.
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Affiliation(s)
- Karsten Baumgärtel
- Dorris Neuroscience Center, Department of Cell Biology, The Scripps Research Institute, La Jolla, California 92037-1000, USA
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Kuiper EFE, Nelemans A, Luiten P, Nijholt I, Dolga A, Eisel U. K(Ca)2 and k(ca)3 channels in learning and memory processes, and neurodegeneration. Front Pharmacol 2012; 3:107. [PMID: 22701424 PMCID: PMC3372087 DOI: 10.3389/fphar.2012.00107] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 05/19/2012] [Indexed: 11/13/2022] Open
Abstract
Calcium-activated potassium (KCa) channels are present throughout the central nervous system as well as many peripheral tissues. Activation of KCa channels contribute to maintenance of the neuronal membrane potential and was shown to underlie the afterhyperpolarization (AHP) that regulates action potential firing and limits the firing frequency of repetitive action potentials. Different subtypes of KCa channels were anticipated on the basis of their physiological and pharmacological profiles, and cloning revealed two well defined but phylogenetic distantly related groups of channels. The group subject of this review includes both the small conductance KCa2 channels (KCa2.1, KCa2.2, and KCa2.3) and the intermediate-conductance (KCa3.1) channel. These channels are activated by submicromolar intracellular Ca2+ concentrations and are voltage independent. Of all KCa channels only the KCa2 channels can be potently but differentially blocked by the bee-venom apamin. In the past few years modulation of KCa channel activation revealed new roles for KCa2 channels in controlling dendritic excitability, synaptic functioning, and synaptic plasticity. Furthermore, KCa2 channels appeared to be involved in neurodegeneration, and learning and memory processes. In this review, we focus on the role of KCa2 and KCa3 channels in these latter mechanisms with emphasis on learning and memory, Alzheimer’s disease and on the interplay between neuroinflammation and different neurotransmitters/neuromodulators, their signaling components and KCa channel activation.
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Affiliation(s)
- Els F E Kuiper
- Molecular Neurobiology, University of Groningen Groningen, Netherlands
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Rahman A, Khan KM, Al-Khaledi G, Khan I, Al-Shemary T. Over activation of hippocampal serine/threonine protein phosphatases PP1 and PP2A is involved in lead-induced deficits in learning and memory in young rats. Neurotoxicology 2012; 33:370-83. [DOI: 10.1016/j.neuro.2012.02.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 02/15/2012] [Accepted: 02/21/2012] [Indexed: 11/27/2022]
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Role of calcineurin in inhibiting disadvantageous associations. Neuroscience 2012; 203:144-52. [PMID: 22230044 DOI: 10.1016/j.neuroscience.2011.12.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 12/06/2011] [Accepted: 12/08/2011] [Indexed: 11/20/2022]
Abstract
Calcineurin is an important calcium-dependent phosphatase that is evolutionarily conserved in all studied species, and has been implicated in the consolidation and maintenance of new memories. However, recent evidence has extended the role of calcineurin. In contrast to learning tasks that require behavioral acquisition, extinction tasks that require behavioral inhibition have been shown to be reliant on calcineurin. In the present study, using a Morris water maze, we have demonstrated that pharmacological inhibition of calcineurin causes augmentation of spatial learning and perseveration of spatial reversal-learning in a dose-dependent manner. Direct infusions of a specific calcineurin inhibitor, cyclosporine A, into the dorsal hippocampi bilaterally, prior to spatial learning, led to increased learning, whereas similar injections of cyclosporine A following a spatial learning task and prior to a spatial reversal-learning task resulted in perseveration of reversal-learning. Our results indicate that injections of cyclosporin A resulted in decreased calcineurin activity in the dorsal hippocampus and increased difficulty in switching to new task demands, in a dose-dependent manner, despite evidence indicating no deficit in ability to learn new information. Therefore, calcineurin activity contributes to the inhibition of previously learned but unwanted behavioral responses during competitive spatial learning. Involvement of calcineurin in extinction of fear memory has recently been demonstrated. Our results also indicate that calcineurin activity plays a role in memory extinction in spatial memory tasks, and therefore, suggest that calcineurin might be an important molecule in mediating behavioral flexibility in general.
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Abstract
Calcium-dependent signals are key triggers of the molecular mechanisms underlying learning and memory and dysregulation of calcium homeostasis in the aging brain has been proposed to underlie aging-dependent cognitive decline. Mechanisms triggered by calcium in neurons include activity-dependent activation of transcription responsible for the synthesis of molecules underlying the long-term changes of neuronal function. Effectors of calcium signaling with a primordial role in transcription regulation are calcium signal-regulated transcription factors. In this review, we summarize the current knowledge of the contribution of key calcium signal-regulated transcription factors, namely CREB, NFAT, and DREAM, to memory formation. We further describe evidence for dysregulation of the activity of these factors during aging.
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Affiliation(s)
- Ana M M Oliveira
- Department of Neurobiology, Interdisciplinary Centre for Neurosciences, University of Heidelberg, Germany
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Oliveira AMM, Estévez MA, Hawk JD, Grimes S, Brindle PK, Abel T. Subregion-specific p300 conditional knock-out mice exhibit long-term memory impairments. Learn Mem 2011; 18:161-9. [PMID: 21345974 DOI: 10.1101/lm.1939811] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Histone acetylation plays a critical role during long-term memory formation. Several studies have demonstrated that the histone acetyltransferase (HAT) CBP is required during long-term memory formation, but the involvement of other HAT proteins has not been extensively investigated. The HATs CBP and p300 have at least 400 described interacting proteins including transcription factors known to play a role in long-term memory formation. Thus, CBP and p300 constitute likely candidates for transcriptional coactivators in memory formation. In this study, we took a loss-of-function approach to evaluate the role of p300 in long-term memory formation. We used conditional knock-out mice in which the deletion of p300 is restricted to the postnatal phase and to subregions of the forebrain. We found that p300 is required for the formation of long-term recognition memory and long-term contextual fear memory in the CA1 area of the hippocampus and cortical areas.
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Affiliation(s)
- Ana M M Oliveira
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
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Hagewoud R, Havekes R, Tiba PA, Novati A, Hogenelst K, Weinreder P, Van der Zee EA, Meerlo P. Coping with sleep deprivation: shifts in regional brain activity and learning strategy. Sleep 2011; 33:1465-73. [PMID: 21102988 DOI: 10.1093/sleep/33.11.1465] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
STUDY OBJECTIVES dissociable cognitive strategies are used for place navigation. Spatial strategies rely on the hippocampus, an area important for flexible integration of novel information. Response strategies are more rigid and involve the dorsal striatum. These memory systems can compensate for each other in case of temporal or permanent damage. Sleep deprivation has adverse effects on hippocampal function. However, whether the striatal memory system can compensate for sleep-deprivation-induced hippocampal impairments is unknown. DESIGN with a symmetrical maze paradigm for mice, we examined the effect of sleep deprivation on learning the location of a food reward (training) and on learning that a previously nonrewarded arm was now rewarded (reversal training). MEASUREMENTS AND RESULTS five hours of sleep deprivation after each daily training session did not affect performance during training. However, in contrast with controls, sleep-deprived mice avoided a hippocampus-dependent spatial strategy and preferentially used a striatum-dependent response strategy. In line with this, the training-induced increase in phosphorylation of the transcription factor cAMP response-element binding protein (CREB) shifted from hippocampus to dorsal striatum. Importantly, although sleep-deprived mice performed well during training, performance during reversal training was attenuated, most likely due to rigidity of the striatal system they used. CONCLUSIONS together, these findings suggest that the brain compensates for negative effects of sleep deprivation on the hippocampal memory system by promoting the use of a striatal memory system. However, effects of sleep deprivation can still appear later on because the alternative learning mechanisms and brain regions involved may result in reduced flexibility under conditions requiring adaptation of previously formed memories.
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Affiliation(s)
- Roelina Hagewoud
- Department of Molecular Neurobiology, University of Groningen, The Netherlands
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Havekes R, Abel T, Van der Zee EA. The cholinergic system and neostriatal memory functions. Behav Brain Res 2010; 221:412-23. [PMID: 21129408 DOI: 10.1016/j.bbr.2010.11.047] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Revised: 11/19/2010] [Accepted: 11/23/2010] [Indexed: 11/25/2022]
Abstract
The striatum is one of the major forebrain regions that strongly expresses muscarinic and nicotinic cholinergic receptors. This article reviews the current knowledge and our new findings about the striatal cholinoceptive organization and its role in a variety of cognitive functions. Pharmacological and genetic manipulations have indicated that the cholinergic and dopaminergic system in the striatum modulate each other's function. In addition to modulating the dopaminergic system, nicotinic cholinergic receptors facilitate GABA release, whereas muscarinic receptors attenuate GABA release. The striatal cholinergic system has also been implicated in various cognitive functions including procedural learning and intradimensional set shifting. Together, these data indicate that the cholinergic system in the striatum is involved in a diverse set of cognitive functions through interactions with other neurotransmitter systems including the dopaminergic and GABAergic systems.
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Affiliation(s)
- Robbert Havekes
- Department of Biology, University of Pennsylvania, 433 S University Avenue, Philadelphia, PA 19104, USA.
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Abstract
It is well established that lead (Pb) exposure in humans leads to learning and memory impairment. However, the biological and molecular mechanisms are still not clearly understood. When over activated, serine/threonine protein phosphatases are known to function as a constraint on learning and memory. Activation of these phosphatases can also result in cytoskeletal changes that will adversely affect learning and memory. We investigated the effects of Pb exposure on these phosphatases in primary cultures of human neurons. Neurons were exposed to physiologically relevant concentrations of Pb (5, 10, 20 and 40 μg/dL) and total phosphatase and PP2A activities were determined in neuronal lysate using para-nitrophenyl phosphate (pNPP), and a PP2A-specific phosphopeptide as substrates. Expression of various serine/threonine phosphatases, tau and its phosphorylation state were determined by Western blot (WB) and immunocytochemistry (ICC). We found that the total phosphatase activity in the neuronal lysate was increased by 30–50% by all the concentrations of Pb tested. PP2A activity was increased by 5 μg/dL Pb only. PP1 expression was increased (ranging from 25–50%) by 10, 20 and 40 μg/dL of Pb. PP2B expression was increased substantially (up to 2.5-fold) by 10 μg/dL Pb, whereas, higher concentrations did not show any effect. On the other hand, Pb (at all concentrations used) decreased expression of PP2A and PP5. Pb exposure induced substantial hyperphosphorylation of tau at serine 199/202 by 5 and 10 μg/dL Pb, and Threonine 231 at higher doses. Expression of total tau was mostly unaffected by lead. Immunocytochemistry data confirmed the WB results of expression of PP1, PP2A, tau protein and the phosphorylation of tau. These results support our hypothesis that Pb exposure up regulates some of the serine/threonine phosphatases (PP1 and PP2B) that are known to impair memory formation, and suggest a novel mechanism of Pb neurotoxicity.
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Spires-Jones TL, Kay K, Matsouka R, Rozkalne A, Betensky RA, Hyman BT. Calcineurin inhibition with systemic FK506 treatment increases dendritic branching and dendritic spine density in healthy adult mouse brain. Neurosci Lett 2010; 487:260-3. [PMID: 20970476 DOI: 10.1016/j.neulet.2010.10.033] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 10/02/2010] [Accepted: 10/13/2010] [Indexed: 10/18/2022]
Abstract
Calcineurin has been implicated as part of a critical signaling pathway for learning and memory, and recent data suggest that calcineurin activation mediates some of the neurotoxicity of the Alzheimer related neurotoxin Aβ. Immunosuppression via calcineurin inhibition with the compound FK506 is an important treatment for organ transplant patients. Here we use Golgi impregnation techniques, along with a new survival analysis-based statistical approach for analysis of dendritic complexity, to show that in healthy adult mice one week of treatment with FK506 affects both the branching patterns and dendritic spine density of cortical neurons. These results indicate that calcineurin inhibition leads to readily detectable changes in brain morphology, further implicating calcineurin related pathways in both the function and structure of the adult brain.
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Affiliation(s)
- Tara L Spires-Jones
- Massachusetts General Hospital/Harvard Medical School, MassGeneral Institute for Neurodegenerative Diseases, 114 16th Street, Charlestown, MA 02129, USA
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Porte Y, Trifilieff P, Wolff M, Micheau J, Buhot M, Mons N. Extinction of spatial memory alters CREB phosphorylation in hippocampal CA1. Hippocampus 2010; 21:1169-79. [DOI: 10.1002/hipo.20844] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2010] [Indexed: 01/07/2023]
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Dong J, Liu W, Wang Y, Xi Q, Chen J. Hypothyroidism following developmental iodine deficiency reduces hippocampal neurogranin, CaMK II and calmodulin and elevates calcineurin in lactational rats. Int J Dev Neurosci 2010; 28:589-96. [DOI: 10.1016/j.ijdevneu.2010.07.230] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 05/26/2010] [Accepted: 07/14/2010] [Indexed: 11/15/2022] Open
Affiliation(s)
- Jing Dong
- Department of Occupational and Environmental HealthSchool of Public HealthChina Medical UniversityShenyangPR China
| | - Wanyang Liu
- Department of Occupational and Environmental HealthSchool of Public HealthChina Medical UniversityShenyangPR China
| | - Yi Wang
- Department of Occupational and Environmental HealthSchool of Public HealthChina Medical UniversityShenyangPR China
| | - Qi Xi
- Department of Occupational and Environmental HealthSchool of Public HealthChina Medical UniversityShenyangPR China
- Department of PhysiologyThe University of Tennessee Health Science CenterRoom 305, Nash Building 894 Union AvenueMemphisTN38163United States
| | - Jie Chen
- Department of Occupational and Environmental HealthSchool of Public HealthChina Medical UniversityShenyangPR China
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Developmental Iodine Deficiency and Hypothyroidism Impair Spatial Memory in Adolescent Rat Hippocampus: Involvement of CaMKII, Calmodulin and Calcineurin. Neurotox Res 2009; 19:81-93. [DOI: 10.1007/s12640-009-9142-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 10/15/2009] [Accepted: 11/20/2009] [Indexed: 10/20/2022]
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22
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Wfs1-deficient mice display impaired behavioural adaptation in stressful environment. Behav Brain Res 2009; 198:334-45. [DOI: 10.1016/j.bbr.2008.11.007] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Revised: 10/28/2008] [Accepted: 11/04/2008] [Indexed: 11/19/2022]
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Hernández-Rabaza V, Llorens-Martín M, Velázquez-Sánchez C, Ferragud A, Arcusa A, Gumus HG, Gómez-Pinedo U, Pérez-Villalba A, Roselló J, Trejo JL, Barcia JA, Canales JJ. Inhibition of adult hippocampal neurogenesis disrupts contextual learning but spares spatial working memory, long-term conditional rule retention and spatial reversal. Neuroscience 2008; 159:59-68. [PMID: 19138728 DOI: 10.1016/j.neuroscience.2008.11.054] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 11/19/2008] [Accepted: 11/20/2008] [Indexed: 11/30/2022]
Abstract
Neurogenesis in the adult dentate gyrus (DG) of the hippocampus has been implicated in neural plasticity and cognition but the specific functions contributed by adult-born neurons remain controversial. Here, we have explored the relationship between adult hippocampal neurogenesis and memory function using tasks which specifically require the participation of the DG. In two separate experiments several groups of rats were exposed to fractionated ionizing radiation (two sessions of 7 Gy each on consecutive days) applied either to the whole brain or focally, aiming at a region overlying the hippocampus. The immunocytochemical assays showed that the radiation significantly reduced the expression of doublecortin (DCX), a marker for immature neurons, in the dorsal DG. Ultrastructural examination of the DG region revealed disruption of progenitor cell niches several weeks after the radiation. In the first experiment, whole-brain and focal irradiation reduced DCX expression by 68% and 43%, respectively. Whole-brain and focally-irradiated rats were unimpaired compared with control rats in a matching-to-place (MTP) working memory task performed in the T-maze and in the long-term retention of the no-alternation rule. In the second experiment, focal irradiation reduced DCX expression by 36% but did not impair performance on (1) a standard non-matching-to-place (NMTP) task, (2) a more demanding NMTP task with increasingly longer within-trial delays, (3) a long-term retention test of the alternation rule and (4) a spatial reversal task. However, rats irradiated focally showed clear deficits in a "purely" contextual fear-conditioning task at short and long retention intervals. These data demonstrate that reduced adult hippocampal neurogenesis produces marked deficits in the rapid acquisition of emotionally relevant contextual information but spares spatial working memory function, the long-term retention of acquired spatial rules and the ability to flexibly modify learned spatial strategies.
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Affiliation(s)
- V Hernández-Rabaza
- Biopsychology and Comparative Neuroscience Unit, Cavanilles Institute (ICBiBE), University of Valencia-General Foundation, Polígono de la Coma s/n, Paterna, 46980 Valencia, Spain
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Rapid encoding of new information alters the profile of plasticity-related mRNA transcripts in the hippocampal CA3 region. Proc Natl Acad Sci U S A 2008; 105:10601-6. [PMID: 18650386 DOI: 10.1073/pnas.0804292105] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A theoretical framework for the function of the medial temporal lobe system in memory defines differential contributions of the hippocampal subregions with regard to pattern recognition retrieval processes and encoding of new information. To investigate molecular programs of relevance, we designed a spatial learning protocol to engage a pattern separation function to encode new information. After background training, two groups of animals experienced the same new training in a novel environment; however, only one group was provided spatial information and demonstrated spatial memory in a retention test. Global transcriptional analysis of the microdissected subregions of the hippocampus exposed a CA3 pattern that was sufficient to clearly segregate spatial learning animals from control. Individual gene and functional group analysis anchored these results to previous work in neural plasticity. From a multitude of expression changes, increases in camk2a, rasgrp1, and nlgn1 were confirmed by in situ hybridization. Furthermore, siRNA inhibition of nlgn1 within the CA3 subregion impaired spatial memory performance, pointing to mechanisms of synaptic remodeling as a basis for rapid encoding of new information in long-term memory.
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Havekes R, Timmer M, Van der Zee EA. Regional differences in hippocampal PKA immunoreactivity after training and reversal training in a spatial Y-maze task. Hippocampus 2007; 17:338-48. [PMID: 17315197 DOI: 10.1002/hipo.20272] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
It is suggested that the hippocampus functions as a comparator by making a comparison between the internal representation and actual sensory information from the environment (for instance, comparing a previously learned location of a food reward with an actual novel location of a food reward in a Y-maze). However, it remains unclear to what extent the various hippocampal regions contribute to this comparator function. One of the proteins known to be crucially involved in the formation of hippocampus-dependent long-term memory is the adenosine 3',5' cyclic monophosphate dependent protein kinase (PKA). Here, we examined region-specific changes in immunoreactivity (ir) of the regulatory IIalpha,beta subunits of PKA (PKA RIIalpha,beta-ir) in the hippocampus during various stages of spatial learning in a Y-maze reference task. Thereafter, we compared changes in hippocampal PKA RIIalpha,beta-ir induced by training and reversal training in which the food reward was relocated to the previously unrewarded arm. We show that: (1) There was a clear correlation between behavioral performance and elevated PKA RIIalpha,beta-ir during the acquisition phase of both training and reversal training in area CA3 and dentate gyrus (DG), (2) PKA RIIalpha,beta-ir was similarly enhanced in area CA1 during the acquisition phase of reversal training, but did not correlate with behavioral performance, (3) PKA RIIalpha,beta-ir did not change during training or reversal training in the subiculum (SUB), (4) No changes in PKA RIIalpha,beta protein levels were found using Western blotting, and (5) AMPA receptor phosphorylation at serine 845 (S845p; the PKA site on the glutamate receptor 1 subunit (GluR1)), was enhanced selectively during the acquisition phase of reversal training. These findings reveal that training and reversal training induce region-specific changes in hippocampal PKA RIIalpha,beta-ir and suggest a differential involvement of hippocampal subregions in match-mismatch detection in case of Y-maze reference learning. Alterations in AMPA receptor regulation at the S845 site seems specifically related to the novelty detector function of the hippocampus important for match-mismatch detection.
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Affiliation(s)
- Robbert Havekes
- Department of Molecular Neurobiology, University of Groningen, Haren, The Netherlands.
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