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Huffels CFM, van Dijk RE, Karst H, Meye FJ, Hol EM, Middeldorp J. Systemic Injection of Aged Blood Plasma in Adult C57BL/6 Mice Induces Neurophysiological Impairments in the Hippocampal CA1. J Alzheimers Dis 2022; 89:283-297. [PMID: 35871343 DOI: 10.3233/jad-220337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Aging is characterized by systemic alterations and forms an important risk factor for Alzheimer's disease. Recently, it has been indicated that blood-borne factors present in the systemic milieu contribute to the aging process. Exposing young mice to aged blood plasma results in impaired neurogenesis and synaptic plasticity in the dentate gyrus, as well as impaired cognition. Vice versa, treating aged mice with young blood plasma rescues impairments associated with aging. OBJECTIVE Whether blood-borne factors are sufficient to drive impairments outside the dentate gyrus, how they impact neurophysiology, and how the functional outcome compares to impairments found in mouse models for AD is still unclear. METHODS Here, we treated adult mice with blood plasma from aged mice and assessed neurophysiological parameters in the hippocampal CA1. RESULTS Mice treated with aged blood plasma show significantly impaired levels of long-term potentiation (LTP), similar to those present in APP/PS1 mice. These impaired levels of LTP in plasma-treated mice are associated with alterations in basic properties of glutamatergic transmission and the enhanced activity of voltage-gated Ca2 + channels. CONCLUSION Together, the data presented in this study show that blood-borne factors are sufficient to drive neurophysiological impairments in the hippocampal CA1.
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Affiliation(s)
- Christiaan F M Huffels
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Roland E van Dijk
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Henk Karst
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Frank J Meye
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Elly M Hol
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Jinte Middeldorp
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands.,Department of Neurobiology & Aging, Biomedical Primate Research Centre, Rijswijk, The Netherlands
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Geoffroy C, Paoletti P, Mony L. Positive allosteric modulation of NMDA receptors: mechanisms, physiological impact and therapeutic potential. J Physiol 2021; 600:233-259. [PMID: 34339523 DOI: 10.1113/jp280875] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 07/28/2021] [Indexed: 12/21/2022] Open
Abstract
NMDA receptors (NMDARs) are glutamate-gated ion channels that play key roles in synaptic transmission and plasticity. Both hyper- and hypo-activation of NMDARs are deleterious to neuronal function. In particular, NMDAR hypofunction is involved in a wide range of neurological and psychiatric conditions like schizophrenia, intellectual disability, age-dependent cognitive decline, or Alzheimer's disease. While early medicinal chemistry efforts were mostly focused on the development of NMDAR antagonists, the last 10 years have seen a boom in the development of NMDAR positive allosteric modulators (PAMs). Here we review the currently developed NMDAR PAMs, their pharmacological profiles and mechanisms of action, as well as their physiological effects in healthy animals and animal models of NMDAR hypofunction. In light of the complexity of physiological outcomes of NMDAR PAMs in vivo, we discuss the remaining challenges and questions that need to be addressed to better grasp and predict the therapeutic potential of NMDAR positive allosteric modulation.
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Affiliation(s)
- Chloé Geoffroy
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, Université PSL, CNRS, INSERM, Paris, France
| | - Pierre Paoletti
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, Université PSL, CNRS, INSERM, Paris, France
| | - Laetitia Mony
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, Université PSL, CNRS, INSERM, Paris, France
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3
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Ivanov AD, Mothet JP. The plastic d-serine signaling pathway: Sliding from neurons to glia and vice-versa. Neurosci Lett 2018; 689:21-25. [PMID: 29852209 DOI: 10.1016/j.neulet.2018.05.039] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 05/23/2018] [Accepted: 05/27/2018] [Indexed: 01/04/2023]
Abstract
d-Serine is now recognized as the main co-agonist for NMDA receptors. For years it was thought to be exclusively produced by astrocytes and was thus viewed as the archetype of gliotransmitters. Recent research have challenged this long cherished and appealing view by showing that in physiological conditions d-erine would rather originate from neurons but not from glia. In the present review and in the light of the emerging serine shuttle model, we ambition to offer a new reading direction of the glia-neuron cross-talk in shaping the metabolism and the functions of d-serine in cerebral communication in normal and pathological conditions by re-interpretating some seminal findings.
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Affiliation(s)
- Andrei D Ivanov
- 'Biophotonics and Synpase Physiopathology' Team, Laboratoire Aimé Cotton, UMR9188 CNRS - ENS, Paris, Saclay, Orsay, France
| | - Jean-Pierre Mothet
- 'Biophotonics and Synpase Physiopathology' Team, Laboratoire Aimé Cotton, UMR9188 CNRS - ENS, Paris, Saclay, Orsay, France.
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4
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Castonguay D, Dufort-Gervais J, Ménard C, Chatterjee M, Quirion R, Bontempi B, Schneider JS, Arnsten AFT, Nairn AC, Norris CM, Ferland G, Bézard E, Gaudreau P, Lombroso PJ, Brouillette J. The Tyrosine Phosphatase STEP Is Involved in Age-Related Memory Decline. Curr Biol 2018; 28:1079-1089.e4. [PMID: 29576474 DOI: 10.1016/j.cub.2018.02.047] [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: 09/27/2017] [Revised: 12/27/2017] [Accepted: 02/19/2018] [Indexed: 01/22/2023]
Abstract
Cognitive disabilities that occur with age represent a growing and expensive health problem. Age-associated memory deficits are observed across many species, but the underlying molecular mechanisms remain to be fully identified. Here, we report elevations in the levels and activity of the striatal-enriched phosphatase (STEP) in the hippocampus of aged memory-impaired mice and rats, in aged rhesus monkeys, and in people diagnosed with amnestic mild cognitive impairment (aMCI). The accumulation of STEP with aging is related to dysfunction of the ubiquitin-proteasome system that normally leads to the degradation of STEP. Higher level of active STEP is linked to enhanced dephosphorylation of its substrates GluN2B and ERK1/2, CREB inactivation, and a decrease in total levels of GluN2B and brain-derived neurotrophic factor (BDNF). These molecular events are reversed in aged STEP knockout and heterozygous mice, which perform similarly to young control mice in the Morris water maze (MWM) and Y-maze tasks. In addition, administration of the STEP inhibitor TC-2153 to old rats significantly improved performance in a delayed alternation T-maze memory task. In contrast, viral-mediated STEP overexpression in the hippocampus is sufficient to induce memory impairment in the MWM and Y-maze tests, and these cognitive deficits are reversed by STEP inhibition. In old LOU/C/Jall rats, a model of healthy aging with preserved memory capacities, levels of STEP and GluN2B are stable, and phosphorylation of GluN2B and ERK1/2 is unaltered. Altogether, these data suggest that elevated levels of STEP that appear with advancing age in several species contribute to the cognitive declines associated with aging.
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Affiliation(s)
- David Castonguay
- Department of Pharmacology and Physiology, Université de Montréal, and Hôpital du Sacré-Coeur de Montréal Research Center, Montreal, QC, Canada
| | - Julien Dufort-Gervais
- Department of Pharmacology and Physiology, Université de Montréal, and Hôpital du Sacré-Coeur de Montréal Research Center, Montreal, QC, Canada
| | - Caroline Ménard
- Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada; Department of Medecine, Université de Montréal, Centre Hospitalier de l'Université de Montréal Research Center, Montreal, QC, Canada
| | - Manavi Chatterjee
- Child Study Center, Yale University School of Medicine, New Haven, CT, USA
| | - Rémi Quirion
- Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada
| | - Bruno Bontempi
- Université de Bordeaux, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
| | - Jay S Schneider
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Amy F T Arnsten
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Angus C Nairn
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Christopher M Norris
- Department of Molecular and Biomedical Pharmacology, Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Guylaine Ferland
- Department of Nutrition, Université de Montréal, and Institut de Cardiologie de Montréal, Montreal, QC, Canada
| | - Erwan Bézard
- Université de Bordeaux, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
| | - Pierrette Gaudreau
- Department of Medecine, Université de Montréal, Centre Hospitalier de l'Université de Montréal Research Center, Montreal, QC, Canada
| | - Paul J Lombroso
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Child Study Center, Yale University School of Medicine, New Haven, CT, USA.
| | - Jonathan Brouillette
- Department of Pharmacology and Physiology, Université de Montréal, and Hôpital du Sacré-Coeur de Montréal Research Center, Montreal, QC, Canada; Child Study Center, Yale University School of Medicine, New Haven, CT, USA.
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Lester AW, Moffat SD, Wiener JM, Barnes CA, Wolbers T. The Aging Navigational System. Neuron 2017; 95:1019-1035. [PMID: 28858613 PMCID: PMC5659315 DOI: 10.1016/j.neuron.2017.06.037] [Citation(s) in RCA: 209] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 06/20/2017] [Accepted: 06/22/2017] [Indexed: 12/17/2022]
Abstract
The discovery of neuronal systems dedicated to computing spatial information, composed of functionally distinct cell types such as place and grid cells, combined with an extensive body of human-based behavioral and neuroimaging research has provided us with a detailed understanding of the brain's navigation circuit. In this review, we discuss emerging evidence from rodents, non-human primates, and humans that demonstrates how cognitive aging affects the navigational computations supported by these systems. Critically, we show 1) that navigational deficits cannot solely be explained by general deficits in learning and memory, 2) that there is no uniform decline across different navigational computations, and 3) that navigational deficits might be sensitive markers for impending pathological decline. Following an introduction to the mechanisms underlying spatial navigation and how they relate to general processes of learning and memory, the review discusses how aging affects the perception and integration of spatial information, the creation and storage of memory traces for spatial information, and the use of spatial information during navigational behavior. The closing section highlights the clinical potential of behavioral and neural markers of spatial navigation, with a particular emphasis on neurodegenerative disorders.
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Affiliation(s)
- Adam W Lester
- Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ 85721, USA; Division of Neural Systems, Memory and Aging, University of Arizona, Tucson, AZ 85721, USA
| | - Scott D Moffat
- School of Psychology, Georgia Institute of Technology, Atlanta, GA 30332 USA
| | - Jan M Wiener
- Department of Psychology, Ageing and Dementia Institute, Bournemouth University, Poole BH12 5BB, UK
| | - Carol A Barnes
- Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ 85721, USA; Division of Neural Systems, Memory and Aging, University of Arizona, Tucson, AZ 85721, USA; Departments of Psychology, Neurology, and Neuroscience, University of Arizona, Tucson, AZ 85721, USA
| | - Thomas Wolbers
- German Center for Neurodegenerative Diseases (DZNE), Aging and Cognition Research Group, 39120 Magdeburg, Germany; Center for Behavioral Brain Sciences (CBBS), 39118 Magdeburg, Germany.
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Labarrière M, Thomas F, Dutar P, Pollegioni L, Wolosker H, Billard JM. Circuit-specific changes in D-serine-dependent activation of the N-methyl-D-aspartate receptor in the aging hippocampus. AGE (DORDRECHT, NETHERLANDS) 2014; 36:9698. [PMID: 25138794 PMCID: PMC4453931 DOI: 10.1007/s11357-014-9698-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 07/27/2014] [Indexed: 05/29/2023]
Abstract
Age-related memory deficits have recently been associated with the impaired expression of D-serine-dependent synaptic plasticity in neuronal networks of the hippocampal CA1 area. However, whether such functional alterations are common to the entire hippocampus during aging remains unknown. Here, we found that D-serine was also required for the induction of N-methyl-D-aspartate receptor (NMDA-R)-dependent long-term potentiation (LTP) at perforant path-granule cell synapses of the dentate gyrus. LTP as well as isolated NMDA-R synaptic potentials were impaired in slices from aged rats, but in contrast to the CA1, this defect was not reversed by exogenous D-serine. The lower activation of the glycine-binding site by the endogenous co-agonist does not therefore appear to be a critical mechanism underlying age-related deficits in NMDA-R activation in the dentate gyrus. Instead, our data highlight the role of changes in presynaptic inputs as illustrated by the weaker responsiveness of afferent glutamatergic fibers, as well as changes in postsynaptic NMDA-R density. Thus, our study indicates that although NMDA-R-dependent mechanisms driving synaptic plasticity are quite similar between hippocampal circuits, they show regional differences in their susceptibility to aging, which could hamper the development of effective therapeutic strategies aimed at reducing cognitive aging.
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Affiliation(s)
- M. Labarrière
- />Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, UMR 894, Paris, 75014 France
| | - F. Thomas
- />Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, UMR 894, Paris, 75014 France
| | - P. Dutar
- />Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, UMR 894, Paris, 75014 France
| | - L. Pollegioni
- />Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell’Insubria, via J.H. Dunant 3, 21100 Varese, Italy
- />The Protein Factory, Centro Interuniversitario di Biotecnologie Proteiche, Politecnico di Milano, ICRM CNR Milano, and Università degli Studi dell’Insubria, via Mancinelli 7, 20137 Milano, Italy
| | - H. Wolosker
- />Department of Biochemistry, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 31036 Israel
| | - J.-M. Billard
- />Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, UMR 894, Paris, 75014 France
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7
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Magnusson KR, Brim BL, Das SR. Selective Vulnerabilities of N-methyl-D-aspartate (NMDA) Receptors During Brain Aging. Front Aging Neurosci 2010; 2:11. [PMID: 20552049 PMCID: PMC2874396 DOI: 10.3389/fnagi.2010.00011] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 03/02/2010] [Indexed: 01/07/2023] Open
Abstract
N-methyl-D-aspartate (NMDA) receptors are present in high density within the cerebral cortex and hippocampus and play an important role in learning and memory. NMDA receptors are negatively affected by aging, but these effects are not uniform in many different ways. This review discusses the selective age-related vulnerabilities of different binding sites of the NMDA receptor complex, different subunits that comprise the complex, and the expression and functions of the receptor within different brain regions. Spatial reference, passive avoidance, and working memory, as well as place field stability and expansion all involve NMDA receptors. Aged animals show deficiencies in these functions, as compared to young, and some studies have identified an association between age-associated changes in the expression of NMDA receptors and poor memory performance. A number of diet and drug interventions have shown potential for reversing or slowing the effects of aging on the NMDA receptor. On the other hand, there is mounting evidence that the NMDA receptors that remain within aged individuals are not always associated with good cognitive functioning. This may be due to a compensatory response of neurons to the decline in NMDA receptor expression or a change in the subunit composition of the remaining receptors. These studies suggest that developing treatments that are aimed at preventing or reversing the effects of aging on the NMDA receptor may aid in ameliorating the memory declines that are associated with aging. However, we need to be mindful of the possibility that there may also be negative consequences in aged individuals.
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Affiliation(s)
- Kathy R Magnusson
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University Corvallis, OR, USA
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Burke SN, Barnes CA. Senescent synapses and hippocampal circuit dynamics. Trends Neurosci 2010; 33:153-61. [PMID: 20071039 DOI: 10.1016/j.tins.2009.12.003] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Revised: 11/30/2009] [Accepted: 12/15/2009] [Indexed: 01/11/2023]
Abstract
Excitatory synaptic transmission is altered during aging in hippocampal granule cells, and in CA3 and CA1 pyramidal cells. These functional changes contribute to age-associated impairments in experimentally-induced plasticity in each of these primary hippocampal subregions. In CA1, plasticity evoked by stimulation shares common mechanisms with the synaptic modification observed following natural behavior. Aging results in deficits in both artificially- and behaviorally-induced plasticity, and this could in part reflect age-related changes in Ca2+ homeostasis. Other observations, however, suggest that increased intracellular Ca2+ levels are beneficial under some circumstances. This review focuses on age-associated changes in synaptic function, how these alterations might contribute to cognitive decline, and the extent to which altered hippocampal circuit properties are detrimental or reflect compensatory processes.
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Affiliation(s)
- Sara N Burke
- Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ 85724, USA
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Differential effects and rates of normal aging in cerebellum and hippocampus. Proc Natl Acad Sci U S A 2010; 107:1624-9. [PMID: 20080589 DOI: 10.1073/pnas.0914207107] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cognitive functions show many alternative outcomes and great individual variation during normal aging. We examined learning over the adult life span in CBA mice, along with morphological and electrophysiological substrates. Our aim was to compare cerebellum-dependent delay eyeblink classical conditioning and hippocampus-dependent contextual fear conditioning in the same animals using the same conditioned and unconditioned stimuli for eyeblink and fear conditioning. In a subset of the behaviorally tested mice, we used unbiased stereology to estimate the total number of Purkinje neurons in cerebellar cortex and pyramidal neurons in the hippocampus. Several forms of synaptic plasticity were assessed at different ages in CBA mice: long-term depression (LTD) in both cerebellum and hippocampus and NMDA-mediated long-term potentiation (LTP) and voltage-dependent calcium channel LTP in hippocampus. Forty-four CBA mice tested at one of five ages (4, 8, 12, 18, or 24 months) demonstrated statistically significant age differences in cerebellum-dependent delay eyeblink conditioning, with 24-month mice showing impairment in comparison with younger mice. These same CBA mice showed no significant differences in contextual or cued fear conditioning. Stereology indicated significant loss of Purkinje neurons in the 18- and 24-month groups, whereas pyramidal neuron numbers were stable across age. Slice electrophysiology recorded from an additional 48 CBA mice indicated significant deficits in LTD appearing in cerebellum between 4 and 8 months, whereas 4- to 12-month mice demonstrated similar hippocampal LTD and LTP values. Our results demonstrate that processes of aging impact brain structures and associated behaviors differentially, with cerebellum showing earlier senescence than hippocampus.
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The effects of aging on N-methyl-D-aspartate receptor subunits in the synaptic membrane and relationships to long-term spatial memory. Neuroscience 2009; 162:933-45. [PMID: 19446010 DOI: 10.1016/j.neuroscience.2009.05.018] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Revised: 04/22/2009] [Accepted: 05/08/2009] [Indexed: 11/23/2022]
Abstract
There are declines in the protein expression of the NR2B (mouse epsilon2) and NR1 (mouse zeta1) subunits of the N-methyl-D-aspartate (NMDA) receptor in the cerebral cortex and hippocampus during aging in C57BL/6 mice. This study was designed to determine if there is a greater effect of aging on subunit expression and a stronger relationship between long-term spatial memory and subunit expression within the synaptic membrane than in the cell as a whole. Male, C57BL/6JNIA mice (4, 11 and 26 months old) were tested for long-term spatial memory in the Morris water maze. Frontal cortex, including prefrontal regions, and hippocampus were homogenized and fractionated into light and synaptosomal membrane fractions. Western blots were used to analyze protein expression of NR2B and NR1 subunits of the NMDA receptor. Old mice performed significantly worse than other ages in the spatial task. In the frontal cortex, the protein levels of the NR2B subunit showed a greater decline with aging in the synaptic membrane fraction than in the whole homogenate, while in the hippocampus a similar age-related decline was observed in both fractions. There were no significant effects of aging on the expression of the NR1 subunit. Within the middle-aged mouse group, higher expression of both NR2B and NR1 subunits in the synaptic membrane of the hippocampus was associated with better memory. In the aged mice, however, higher expression of both subunits was associated with poorer memory. These results indicate that aging could be altering the localization of the NR2B subunit to the synaptic membrane within the frontal cortex. The correlational results suggest that NMDA receptor functions, receptor subunit composition, and/or the environment in which the receptor interacted in the hippocampus were not the same in the old animals as in younger mice and this may have contributed to memory declines during aging.
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