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Erdinger S, Amrein I, Back M, Ludewig S, Korte M, von Engelhardt J, Wolfer DP, Müller UC. Lack of APLP1 leads to subtle alterations in neuronal morphology but does not affect learning and memory. Front Mol Neurosci 2022; 15:1028836. [DOI: 10.3389/fnmol.2022.1028836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 10/11/2022] [Indexed: 11/13/2022] Open
Abstract
The amyloid precursor protein APP plays a crucial role in Alzheimer pathogenesis. Its physiological functions, however, are only beginning to be unraveled. APP belongs to a small gene family, including besides APP the closely related amyloid precursor-like proteins APLP1 and APLP2, that all constitute synaptic adhesion proteins. While APP and APLP2 are ubiquitously expressed, APLP1 is specific for the nervous system. Previous genetic studies, including combined knockouts of several family members, pointed towards a unique role for APLP1, as only APP/APLP1 double knockouts were viable. We now examined brain and neuronal morphology in APLP1 single knockout (KO) animals, that have to date not been studied in detail. Here, we report that APLP1-KO mice show normal spine density in hippocampal CA1 pyramidal cells and subtle alterations in dendritic complexity. Extracellular field recordings revealed normal basal synaptic transmission and no alterations in synaptic plasticity (LTP). Further, behavioral studies revealed in APLP1-KO mice a small deficit in motor function and reduced diurnal locomotor activity, while learning and memory were not affected by the loss of APLP1. In summary, our study indicates that APP family members serve both distinct and overlapping functions that need to be considered for therapeutic treatments of Alzheimer’s disease.
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Bold CS, Baltissen D, Ludewig S, Back MK, Just J, Kilian L, Erdinger S, Banicevic M, Rehra L, Almouhanna F, Nigri M, Wolfer DP, Spilger R, Rohr K, Kann O, Buchholz CJ, von Engelhardt J, Korte M, Müller UC. APPsα Rescues Tau-Induced Synaptic Pathology. J Neurosci 2022; 42:5782-5802. [PMID: 35667850 PMCID: PMC9302470 DOI: 10.1523/jneurosci.2200-21.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 04/06/2022] [Accepted: 05/22/2022] [Indexed: 01/22/2023] Open
Abstract
Alzheimer's disease (AD) is histopathologically characterized by Aβ plaques and the accumulation of hyperphosphorylated Tau species, the latter also constituting key hallmarks of primary tauopathies. Whereas Aβ is produced by amyloidogenic APP processing, APP processing along the competing nonamyloidogenic pathway results in the secretion of neurotrophic and synaptotrophic APPsα. Recently, we demonstrated that APPsα has therapeutic effects in transgenic AD model mice and rescues Aβ-dependent impairments. Here, we examined the potential of APPsα to mitigate Tau-induced synaptic deficits in P301S mice (both sexes), a widely used mouse model of tauopathy. Analysis of synaptic plasticity revealed an aberrantly increased LTP in P301S mice that could be normalized by acute application of nanomolar amounts of APPsα to hippocampal slices, indicating a homeostatic function of APPsα on a rapid time scale. Further, AAV-mediated in vivo expression of APPsα restored normal spine density of CA1 neurons even at stages of advanced Tau pathology not only in P301S mice, but also in independent THY-Tau22 mice. Strikingly, when searching for the mechanism underlying aberrantly increased LTP in P301S mice, we identified an early and progressive loss of major GABAergic interneuron subtypes in the hippocampus of P301S mice, which may lead to reduced GABAergic inhibition of principal cells. Interneuron loss was paralleled by deficits in nest building, an innate behavior highly sensitive to hippocampal impairments. Together, our findings indicate that APPsα has therapeutic potential for Tau-mediated synaptic dysfunction and suggest that loss of interneurons leads to disturbed neuronal circuits that compromise synaptic plasticity as well as behavior.SIGNIFICANCE STATEMENT Our findings indicate, for the first time, that APPsα has the potential to rescue Tau-induced spine loss and abnormal synaptic plasticity. Thus, APPsα might have therapeutic potential not only because of its synaptotrophic functions, but also its homeostatic capacity for neuronal network activity. Hence, APPsα is one of the few molecules which has proven therapeutic effects in mice, both for Aβ- and Tau-dependent synaptic impairments and might therefore have therapeutic potential for patients suffering from AD or primary tauopathies. Furthermore, we found in P301S mice a pronounced reduction of inhibitory interneurons as the earliest pathologic event preceding the accumulation of hyperphosphorylated Tau species. This loss of interneurons most likely disturbs neuronal circuits that are important for synaptic plasticity and behavior.
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Affiliation(s)
- Charlotte S Bold
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht Karls Universität Heidelberg, Heidelberg, 69120, Germany
| | - Danny Baltissen
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht Karls Universität Heidelberg, Heidelberg, 69120, Germany
| | - Susann Ludewig
- TU Braunschweig, Zoological Institute, Braunschweig, 38106, Germany
- Helmholtz Centre for Infection Research, Neuroinflammation and Neurodegeneration Group, Braunschweig, 38124, Germany
| | - Michaela K Back
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, 55128, Germany
| | - Jennifer Just
- TU Braunschweig, Zoological Institute, Braunschweig, 38106, Germany
| | - Lara Kilian
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht Karls Universität Heidelberg, Heidelberg, 69120, Germany
| | - Susanne Erdinger
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht Karls Universität Heidelberg, Heidelberg, 69120, Germany
| | - Marija Banicevic
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht Karls Universität Heidelberg, Heidelberg, 69120, Germany
| | - Lena Rehra
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht Karls Universität Heidelberg, Heidelberg, 69120, Germany
| | - Fadi Almouhanna
- Institute of Physiology and Pathophysiology, Ruprecht Karls Universität Heidelberg, Heidelberg, 69120, Germany
| | - Martina Nigri
- Institute of Anatomy, University of Zurich, Zurich, 8057, Switzerland
| | - David P Wolfer
- Institute of Anatomy, University of Zurich, Zurich, 8057, Switzerland
- Institute of Human Movement Sciences and Sport, ETH Zurich, Zurich, Switzerland
| | - Roman Spilger
- BioQuant Center, Institute of Pharmacy and Molecular Biotechnology, Ruprecht Karls Universität Heidelberg and DKFZ, Heidelberg, 69120, Germany
| | - Karl Rohr
- BioQuant Center, Institute of Pharmacy and Molecular Biotechnology, Ruprecht Karls Universität Heidelberg and DKFZ, Heidelberg, 69120, Germany
| | - Oliver Kann
- Institute of Physiology and Pathophysiology, Ruprecht Karls Universität Heidelberg, Heidelberg, 69120, Germany
| | | | - Jakob von Engelhardt
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, 55128, Germany
| | - Martin Korte
- TU Braunschweig, Zoological Institute, Braunschweig, 38106, Germany
- Helmholtz Centre for Infection Research, Neuroinflammation and Neurodegeneration Group, Braunschweig, 38124, Germany
| | - Ulrike C Müller
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht Karls Universität Heidelberg, Heidelberg, 69120, Germany
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Hetsch F, Wang D, Chen X, Zhang J, Aslam M, Kegel M, Tonner H, Grus F, von Engelhardt J. CKAMP44 controls synaptic function and strength of relay neurons during early development of the dLGN. J Physiol 2022; 600:3549-3565. [PMID: 35770953 DOI: 10.1113/jp283172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/27/2022] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Expression of CKAMP44 starts early during development of the dLGN and remains stable in relay neurons and interneurons. Genetic deletion of CKAMP44 decreases synaptic strength and increases silent synapse number in dLGN relay neurons. Genetic deletion of CKAMP44 increases the rate of recovery from desensitisation of AMPA receptors in dLGN relay neurons. Genetic deletion of CKAMP44 reduces synaptic short-term depression in retinogeniculate synapses. The probability to induce plateau potentials is elevated in relay neurons of CKAMP44-/- mice. Eye-specific input segregation is unaffected in the dLGN of CKAMP44-/- mice. Deletion of CKAMP44 mildly affects dendritic arborisation of relay neurons in the dLGN. ABSTRACT Relay neurons of the dorsal lateral geniculate nucleus (dLGN) receive inputs from retinal ganglion cells via retinogeniculate synapses. These connections undergo pruning in the first two weeks after eye opening. The remaining connections are strengthened several-fold by the insertion of AMPA receptors (AMPARs) into weak or silent synapses. In this study, we found that the AMPAR auxiliary subunit CKAMP44 is required for receptor insertion and function of retinogeniculate synapses during development. Genetic deletion of CKAMP44 resulted in decreased synaptic strength and a higher number of silent synapses in young (P9-11) mice. Recovery from desensitisation of AMPA receptors was faster in CKAMP44 knockout (CKAMP44-/- ) than in wildtype mice. Moreover, loss of CKAMP44 increased the probability to induce plateau potentials, which are known to be important for eye-specific input segregation and retinogeniculate synapse maturation. The anatomy of relay neurons in the dLGN was changed in young CKAMP44-/- mice showing a transient increase in dendritic branching that normalised during later development (P26-33). Interestingly, input segregation in young CKAMP44-/- mice was not affected when compared to wildtype mice. These results demonstrate that CKAMP44 promotes maturation and modulates function of retinogeniculate synapses during early development of the visual system without affecting input segregation. Abstract figure legend AMPA receptor auxiliary subunit CKAMP44 influences synaptic function in retinogeniculate synapses of young mice. CKAMP44 unsilences synapses by recruiting AMPA receptors to the synapse. Furthermore, genetic deletion of CKAMP44 reduces short-term depression and increases the probability to elicit L-type Ca2+ channel-mediated plateau potentials. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Florian Hetsch
- Institute of Pathophysiology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128, Mainz, Germany
| | - Danni Wang
- Institute of Pathophysiology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128, Mainz, Germany
| | - Xufeng Chen
- Institute of Pathophysiology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128, Mainz, Germany
| | - Jiong Zhang
- Institute of Pathophysiology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128, Mainz, Germany
| | - Muhammad Aslam
- Institute of Pathophysiology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128, Mainz, Germany
| | - Marcel Kegel
- Institute of Pathophysiology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128, Mainz, Germany
| | - Henrik Tonner
- Experimental Ophthalmology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, 55131, Mainz, Germany
| | - Franz Grus
- Experimental Ophthalmology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, 55131, Mainz, Germany
| | - Jakob von Engelhardt
- Institute of Pathophysiology, Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128, Mainz, Germany
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Hanuscheck N, Thalman C, Domingues M, Schmaul S, Muthuraman M, Hetsch F, Ecker M, Endle H, Oshaghi M, Martino G, Kuhlmann T, Bozek K, van Beers T, Bittner S, von Engelhardt J, Vogt J, Vogelaar CF, Zipp F. Interleukin-4 receptor signaling modulates neuronal network activity. J Exp Med 2022; 219:213227. [PMID: 35587822 PMCID: PMC9123307 DOI: 10.1084/jem.20211887] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 12/13/2021] [Accepted: 04/29/2022] [Indexed: 11/25/2022] Open
Abstract
Evidence is emerging that immune responses not only play a part in the central nervous system (CNS) in diseases but may also be relevant for healthy conditions. We discovered a major role for the interleukin-4 (IL-4)/IL-4 receptor alpha (IL-4Rα) signaling pathway in synaptic processes, as indicated by transcriptome analysis in IL-4Rα–deficient mice and human neurons with/without IL-4 treatment. Moreover, IL-4Rα is expressed presynaptically, and locally available IL-4 regulates synaptic transmission. We found reduced synaptic vesicle pools, altered postsynaptic currents, and a higher excitatory drive in cortical networks of IL-4Rα–deficient neurons. Acute effects of IL-4 treatment on postsynaptic currents in wild-type neurons were mediated via PKCγ signaling release and led to increased inhibitory activity supporting the findings in IL-4Rα–deficient neurons. In fact, the deficiency of IL-4Rα resulted in increased network activity in vivo, accompanied by altered exploration and anxiety-related learning behavior; general learning and memory was unchanged. In conclusion, neuronal IL-4Rα and its presynaptic prevalence appear relevant for maintaining homeostasis of CNS synaptic function.
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Affiliation(s)
- Nicholas Hanuscheck
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Carine Thalman
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Micaela Domingues
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Samantha Schmaul
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Muthuraman Muthuraman
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Florian Hetsch
- Institute for Pathophysiology, Focus Program Translational Neuroscience, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Manuela Ecker
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Heiko Endle
- Department of Molecular and Translational Neuroscience, Cluster of Excellence-Cellular Stress Response in Aging-Associated Diseases and Center of Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Mohammadsaleh Oshaghi
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Gianvito Martino
- Neuroimmunology Unit, Institute of Experimental Neurology, Division of Neuroscience, IRCCS San Raffaele Scientific Institute and Vita Salute San Raffaele University, Milan, Italy
| | - Tanja Kuhlmann
- Institute for Neuropathology, University Hospital Münster, Münster, Germany
| | - Katarzyna Bozek
- Center for Molecular Medicine, Faculty of Medicine and University Hospital Cologne; University of Cologne, Cologne, Germany
| | - Tim van Beers
- Molecular Cell Biology, Institute I of Anatomy, University of Cologne, Cologne, Germany
| | - Stefan Bittner
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Jakob von Engelhardt
- Institute for Pathophysiology, Focus Program Translational Neuroscience, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Johannes Vogt
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.,Department of Molecular and Translational Neuroscience, Cluster of Excellence-Cellular Stress Response in Aging-Associated Diseases and Center of Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Christina Francisca Vogelaar
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Frauke Zipp
- Department of Neurology, Focus Program Translational Neuroscience and Immunotherapy, Rhine Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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Luck R, Karakatsani A, Shah B, Schermann G, Adler H, Kupke J, Tisch N, Jeong HW, Back MK, Hetsch F, D'Errico A, De Palma M, Wiedtke E, Grimm D, Acker-Palmer A, von Engelhardt J, Adams RH, Augustin HG, Ruiz de Almodóvar C. The angiopoietin-Tie2 pathway regulates Purkinje cell dendritic morphogenesis in a cell-autonomous manner. Cell Rep 2021; 36:109522. [PMID: 34407407 PMCID: PMC9110807 DOI: 10.1016/j.celrep.2021.109522] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 04/06/2021] [Accepted: 07/22/2021] [Indexed: 01/01/2023] Open
Abstract
Neuro-vascular communication is essential to synchronize central nervous system development. Here, we identify angiopoietin/Tie2 as a neuro-vascular signaling axis involved in regulating dendritic morphogenesis of Purkinje cells (PCs). We show that in the developing cerebellum Tie2 expression is not restricted to blood vessels, but it is also present in PCs. Its ligands angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2) are expressed in neural cells and endothelial cells (ECs), respectively. PC-specific deletion of Tie2 results in reduced dendritic arborization, which is recapitulated in neural-specific Ang1-knockout and Ang2 full-knockout mice. Mechanistically, RNA sequencing reveals that Tie2-deficient PCs present alterations in gene expression of multiple genes involved in cytoskeleton organization, dendritic formation, growth, and branching. Functionally, mice with deletion of Tie2 in PCs present alterations in PC network functionality. Altogether, our data propose Ang/Tie2 signaling as a mediator of intercellular communication between neural cells, ECs, and PCs, required for proper PC dendritic morphogenesis and function.
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Affiliation(s)
- Robert Luck
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Andromachi Karakatsani
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Bhavin Shah
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Geza Schermann
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Heike Adler
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Janina Kupke
- Department of Neurobiology, Interdisciplinary Centre for Neurosciences (IZN), University of Heidelberg, 69120 Heidelberg, Germany
| | - Nathalie Tisch
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Hyun-Woo Jeong
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, and University of Münster, Faculty of Medicine, 48149 Münster, Germany
| | - Michaela Kerstin Back
- Institute of Pathophysiology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | - Florian Hetsch
- Institute of Pathophysiology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | - Anna D'Errico
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, 60323 Frankfurt, Germany
| | - Michele De Palma
- Swiss Institute for Experimental Cancer Research (ISREC), Swiss Federal Institute of Technology in Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Ellen Wiedtke
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Bioquant Center, 69120 Heidelberg, Germany
| | - Dirk Grimm
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Bioquant Center, 69120 Heidelberg, Germany; German Center for Infection Research (DZIF), and German Center for Cardiovascular Research (DZHK), Heidelberg, Germany
| | - Amparo Acker-Palmer
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, 60323 Frankfurt, Germany
| | - Jakob von Engelhardt
- Institute of Pathophysiology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | - Ralf H Adams
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, and University of Münster, Faculty of Medicine, 48149 Münster, Germany
| | - Hellmut G Augustin
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany; Division of Vascular Oncology and Metastasis, German Cancer Research Center Heidelberg (DKFZ-ZMBH Alliance), 69120 Heidelberg, Germany
| | - Carmen Ruiz de Almodóvar
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany.
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6
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von Engelhardt J. Role of AMPA receptor desensitization in short term depression - lessons from retinogeniculate synapses. J Physiol 2021; 600:201-215. [PMID: 34197645 DOI: 10.1113/jp280878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 06/28/2021] [Indexed: 12/22/2022] Open
Abstract
Repetitive synapse activity induces various forms of short-term plasticity. The role of presynaptic mechanisms such as residual Ca2+ and vesicle depletion in short-term facilitation and short-term depression is well established. On the other hand, the contribution of postsynaptic mechanisms such as receptor desensitization and saturation to short-term plasticity is less well known and often ignored. In this review, I will describe short-term plasticity in retinogeniculate synapses of relay neurons of the dorsal lateral geniculate nucleus (dLGN) to exemplify the synaptic properties that facilitate the contribution of AMPA receptor desensitization to short-term plasticity. These include high vesicle release probability, glutamate spillover and, importantly, slow recovery from desensitization of AMPA receptors. The latter is strongly regulated by the interaction of AMPA receptors with auxiliary proteins such as CKAMP44. Finally, I discuss the relevance of short-term plasticity in retinogeniculate synapses for the processing of visual information by LGN relay neurons.
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Affiliation(s)
- Jakob von Engelhardt
- Institute of Pathophysiology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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7
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Steubler V, Erdinger S, Back MK, Ludewig S, Fässler D, Richter M, Han K, Slomianka L, Amrein I, von Engelhardt J, Wolfer DP, Korte M, Müller UC. Loss of all three APP family members during development impairs synaptic function and plasticity, disrupts learning, and causes an autism-like phenotype. EMBO J 2021; 40:e107471. [PMID: 34008862 PMCID: PMC8204861 DOI: 10.15252/embj.2020107471] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/29/2021] [Accepted: 04/01/2021] [Indexed: 12/15/2022] Open
Abstract
The key role of APP for Alzheimer pathogenesis is well established. However, perinatal lethality of germline knockout mice lacking the entire APP family has so far precluded the analysis of its physiological functions for the developing and adult brain. Here, we generated conditional APP/APLP1/APLP2 triple KO (cTKO) mice lacking the APP family in excitatory forebrain neurons from embryonic day 11.5 onwards. NexCre cTKO mice showed altered brain morphology with agenesis of the corpus callosum and disrupted hippocampal lamination. Further, NexCre cTKOs revealed reduced basal synaptic transmission and drastically reduced long-term potentiation that was associated with reduced dendritic length and reduced spine density of pyramidal cells. With regard to behavior, lack of the APP family leads not only to severe impairments in a panel of tests for learning and memory, but also to an autism-like phenotype including repetitive rearing and climbing, impaired social communication, and deficits in social interaction. Together, our study identifies essential functions of the APP family during development, for normal hippocampal function and circuits important for learning and social behavior.
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Affiliation(s)
- Vicky Steubler
- Department of Functional GenomicsInstitute of Pharmacy and Molecular BiotechnologyHeidelberg UniversityHeidelbergGermany
| | - Susanne Erdinger
- Department of Functional GenomicsInstitute of Pharmacy and Molecular BiotechnologyHeidelberg UniversityHeidelbergGermany
| | - Michaela K Back
- Institute of PathophysiologyFocus Program Translational Neuroscience (FTN)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Susann Ludewig
- Division of Cellular NeurobiologyZoological Institute, TU BraunschweigBraunschweigGermany
- Helmholtz Centre for Infection Research, Neuroinflammation and Neurodegeneration GroupBraunschweigGermany
| | - Dominique Fässler
- Department of Functional GenomicsInstitute of Pharmacy and Molecular BiotechnologyHeidelberg UniversityHeidelbergGermany
| | - Max Richter
- Department of Functional GenomicsInstitute of Pharmacy and Molecular BiotechnologyHeidelberg UniversityHeidelbergGermany
| | - Kang Han
- Department of Functional GenomicsInstitute of Pharmacy and Molecular BiotechnologyHeidelberg UniversityHeidelbergGermany
| | - Lutz Slomianka
- Institute of Anatomy and Zurich Center for Integrative Human PhysiologyUniversity of ZurichZurichSwitzerland
| | - Irmgard Amrein
- Institute of Anatomy and Zurich Center for Integrative Human PhysiologyUniversity of ZurichZurichSwitzerland
| | - Jakob von Engelhardt
- Institute of PathophysiologyFocus Program Translational Neuroscience (FTN)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - David P Wolfer
- Institute of Anatomy and Zurich Center for Integrative Human PhysiologyUniversity of ZurichZurichSwitzerland
- Institute of Human Movement SciencesETH ZurichZurichSwitzerland
| | - Martin Korte
- Division of Cellular NeurobiologyZoological Institute, TU BraunschweigBraunschweigGermany
- Helmholtz Centre for Infection Research, Neuroinflammation and Neurodegeneration GroupBraunschweigGermany
| | - Ulrike C Müller
- Department of Functional GenomicsInstitute of Pharmacy and Molecular BiotechnologyHeidelberg UniversityHeidelbergGermany
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8
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Back MK, Ruggieri S, Jacobi E, von Engelhardt J. Amyloid Beta-Mediated Changes in Synaptic Function and Spine Number of Neocortical Neurons Depend on NMDA Receptors. Int J Mol Sci 2021; 22:ijms22126298. [PMID: 34208315 PMCID: PMC8231237 DOI: 10.3390/ijms22126298] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/07/2021] [Accepted: 06/09/2021] [Indexed: 11/16/2022] Open
Abstract
Onset and progression of Alzheimer's disease (AD) pathophysiology differs between brain regions. The neocortex, for example, is a brain region that is affected very early during AD. NMDA receptors (NMDARs) are involved in mediating amyloid beta (Aβ) toxicity. NMDAR expression, on the other hand, can be affected by Aβ. We tested whether the high vulnerability of neocortical neurons for Aβ-toxicity may result from specific NMDAR expression profiles or from a particular regulation of NMDAR expression by Aβ. Electrophysiological analyses suggested that pyramidal cells of 6-months-old wildtype mice express mostly GluN1/GluN2A NMDARs. While synaptic NMDAR-mediated currents are unaltered in 5xFAD mice, extrasynaptic NMDARs seem to contain GluN1/GluN2A and GluN1/GluN2A/GluN2B. We used conditional GluN1 and GluN2B knockout mice to investigate whether NMDARs contribute to Aβ-toxicity. Spine number was decreased in pyramidal cells of 5xFAD mice and increased in neurons with 3-week virus-mediated Aβ-overexpression. NMDARs were required for both Aβ-mediated changes in spine number and functional synapses. Thus, our study gives novel insights into the Aβ-mediated regulation of NMDAR expression and the role of NMDARs in Aβ pathophysiology in the somatosensory cortex.
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9
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Aslam M, Kandasamy N, Ullah A, Paramasivam N, Öztürk MA, Naureen S, Arshad A, Badshah M, Khan K, Wajid M, Abbasi R, Ilyas M, Eils R, Schlesner M, Wade RC, Ahmad N, von Engelhardt J. Putative second hit rare genetic variants in families with seemingly GBA-associated Parkinson's disease. NPJ Genom Med 2021; 6:2. [PMID: 33402667 PMCID: PMC7785741 DOI: 10.1038/s41525-020-00163-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 11/12/2020] [Indexed: 11/08/2022] Open
Abstract
Rare variants in the beta-glucocerebrosidase gene (GBA1) are common genetic risk factors for alpha synucleinopathy, which often manifests clinically as GBA-associated Parkinson's disease (GBA-PD). Clinically, GBA-PD closely mimics idiopathic PD, but it may present at a younger age and often aggregates in families. Most carriers of GBA variants are, however, asymptomatic. Moreover, symptomatic PD patients without GBA variant have been reported in families with seemingly GBA-PD. These observations obscure the link between GBA variants and PD pathogenesis and point towards a role for unidentified additional genetic and/or environmental risk factors or second hits in GBA-PD. In this study, we explored whether rare genetic variants may be additional risk factors for PD in two families segregating the PD-associated GBA1 variants c.115+1G>A (ClinVar ID: 93445) and p.L444P (ClinVar ID: 4288). Our analysis identified rare genetic variants of the HSP70 co-chaperone DnaJ homolog subfamily B member 6 (DNAJB6) and lysosomal protein prosaposin (PSAP) as additional factors possibly influencing PD risk in the two families. In comparison to the wild-type proteins, variant DNAJB6 and PSAP proteins show altered functions in the context of cellular alpha-synuclein homeostasis when expressed in reporter cells. Furthermore, the segregation pattern of the rare variants in the genes encoding DNAJB6 and PSAP indicated a possible association with PD in the respective families. The occurrence of second hits or additional PD cosegregating rare variants has important implications for genetic counseling in PD families with GBA1 variant carriers and for the selection of PD patients for GBA targeted treatments.
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Affiliation(s)
- Muhammad Aslam
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.
| | - Nirosiya Kandasamy
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Anwar Ullah
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
- Department of Biochemistry, Quaid-i-Azam University, Islamabad, Pakistan
| | - Nagarajan Paramasivam
- Heidelberg Center for Personalized Oncology (DKFZ-HIPO), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Mehmet Ali Öztürk
- Molecular and Cellular Modeling Group, Heidelberg Institute of Theoretical Studies (HITS), Heidelberg, Germany
- The Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104, Freiburg, Germany
| | - Saima Naureen
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Department of Zoology, PMAS-Arid Agriculture University, Rawalpindi, Pakistan
| | - Abida Arshad
- Department of Zoology, PMAS-Arid Agriculture University, Rawalpindi, Pakistan
| | - Mazhar Badshah
- Department of Neurology, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Kafaitullah Khan
- Department of Microbiology, University of Balochistan, Quetta, Pakistan
| | - Muhammad Wajid
- Department of Biological Sciences, University of Okara, Okara, Pakistan
| | - Rashda Abbasi
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Muhammad Ilyas
- Faculty of Mechanical Engineering, GIK Institute of Engineering Sciences and Technology, Topi, 23460, Pakistan
| | - Roland Eils
- Center for Digital Health, Berlin Institute of Health and Charité Universitätsmedizin Berlin, Berlin, Germany
- Health Data Science Unit, Bioquant, Medical Faculty, University of Heidelberg, Heidelberg, Germany
| | - Matthias Schlesner
- Bioinformatics and Omics Data Analytics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Rebecca C Wade
- Molecular and Cellular Modeling Group, Heidelberg Institute of Theoretical Studies (HITS), Heidelberg, Germany
- Center for Molecular Biology of the University of Heidelberg (ZMBH), DKFZ-ZMBH Alliance, and Interdisciplinary Center for Scientific Computing (IWR), Heidelberg, Germany
| | - Nafees Ahmad
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Jakob von Engelhardt
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.
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Pfisterer U, Petukhov V, Demharter S, Meichsner J, Thompson JJ, Batiuk MY, Asenjo-Martinez A, Vasistha NA, Thakur A, Mikkelsen J, Adorjan I, Pinborg LH, Pers TH, von Engelhardt J, Kharchenko PV, Khodosevich K. Author Correction: Identification of epilepsy-associated neuronal subtypes and gene expression underlying epileptogenesis. Nat Commun 2020; 11:5988. [PMID: 33214565 PMCID: PMC7678822 DOI: 10.1038/s41467-020-19869-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Ulrich Pfisterer
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Viktor Petukhov
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark.,Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA
| | - Samuel Demharter
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Johanna Meichsner
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Jonatan J Thompson
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Mykhailo Y Batiuk
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Andrea Asenjo-Martinez
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Navneet A Vasistha
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Ashish Thakur
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Jens Mikkelsen
- Department of Neurology and Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Istvan Adorjan
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
| | - Lars H Pinborg
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, 2200, Copenhagen, Denmark.,Epilepsy Clinic, Department of Neurology, Copenhagen University Hospital, Rigshospitalet, 2200, Copenhagen, Denmark
| | - Tune H Pers
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Jakob von Engelhardt
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Peter V Kharchenko
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA
| | - Konstantin Khodosevich
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark.
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11
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Pfisterer U, Petukhov V, Demharter S, Meichsner J, Thompson JJ, Batiuk MY, Asenjo-Martinez A, Vasistha NA, Thakur A, Mikkelsen J, Adorjan I, Pinborg LH, Pers TH, von Engelhardt J, Kharchenko PV, Khodosevich K. Identification of epilepsy-associated neuronal subtypes and gene expression underlying epileptogenesis. Nat Commun 2020; 11:5038. [PMID: 33028830 PMCID: PMC7541486 DOI: 10.1038/s41467-020-18752-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 09/08/2020] [Indexed: 11/20/2022] Open
Abstract
Epilepsy is one of the most common neurological disorders, yet its pathophysiology is poorly understood due to the high complexity of affected neuronal circuits. To identify dysfunctional neuronal subtypes underlying seizure activity in the human brain, we have performed single-nucleus transcriptomics analysis of >110,000 neuronal transcriptomes derived from temporal cortex samples of multiple temporal lobe epilepsy and non-epileptic subjects. We found that the largest transcriptomic changes occur in distinct neuronal subtypes from several families of principal neurons (L5-6_Fezf2 and L2-3_Cux2) and GABAergic interneurons (Sst and Pvalb), whereas other subtypes in the same families were less affected. Furthermore, the subtypes with the largest epilepsy-related transcriptomic changes may belong to the same circuit, since we observed coordinated transcriptomic shifts across these subtypes. Glutamate signaling exhibited one of the strongest dysregulations in epilepsy, highlighted by layer-wise transcriptional changes in multiple glutamate receptor genes and strong upregulation of genes coding for AMPA receptor auxiliary subunits. Overall, our data reveal a neuronal subtype-specific molecular phenotype of epilepsy. The pathophysiology of epilepsy is unclear. Here, the authors present single-nuclei transcriptomic profiling of human temporal lobe epilepsy from patients. They identified epilepsy-associated neuronal subtypes, and a panel of dysregulated genes, predicting neuronal circuits contributing to epilepsy.
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Affiliation(s)
- Ulrich Pfisterer
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Viktor Petukhov
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark.,Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA
| | - Samuel Demharter
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Johanna Meichsner
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Jonatan J Thompson
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Mykhailo Y Batiuk
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Andrea Asenjo-Martinez
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Navneet A Vasistha
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Ashish Thakur
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Jens Mikkelsen
- Department of Neurology and Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Istvan Adorjan
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
| | - Lars H Pinborg
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, 2200, Copenhagen, Denmark.,Epilepsy Clinic, Department of Neurology, Copenhagen University Hospital, Rigshospitalet, 2200, Copenhagen, Denmark
| | - Tune H Pers
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Jakob von Engelhardt
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Peter V Kharchenko
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA
| | - Konstantin Khodosevich
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark.
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12
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Mehr A, Hick M, Ludewig S, Müller M, Herrmann U, von Engelhardt J, Wolfer DP, Korte M, Müller UC. Lack of APP and APLP2 in GABAergic Forebrain Neurons Impairs Synaptic Plasticity and Cognition. Cereb Cortex 2020; 30:4044-4063. [PMID: 32219307 DOI: 10.1093/cercor/bhaa025] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Amyloid-β precursor protein (APP) is central to the pathogenesis of Alzheimer's disease, yet its physiological functions remain incompletely understood. Previous studies had indicated important synaptic functions of APP and the closely related homologue APLP2 in excitatory forebrain neurons for spine density, synaptic plasticity, and behavior. Here, we show that APP is also widely expressed in several interneuron subtypes, both in hippocampus and cortex. To address the functional role of APP in inhibitory neurons, we generated mice with a conditional APP/APLP2 double knockout (cDKO) in GABAergic forebrain neurons using DlxCre mice. These DlxCre cDKO mice exhibit cognitive deficits in hippocampus-dependent spatial learning and memory tasks, as well as impairments in species-typic nesting and burrowing behaviors. Deficits at the behavioral level were associated with altered neuronal morphology and synaptic plasticity Long-Term Potentiation (LTP). Impaired basal synaptic transmission at the Schafer collateral/CA1 pathway, which was associated with altered compound excitatory/inhibitory synaptic currents and reduced action potential firing of CA1 pyramidal cells, points to a disrupted excitation/inhibition balance in DlxCre cDKOs. Together, these impairments may lead to hippocampal dysfunction. Collectively, our data reveal a crucial role of APP family proteins in inhibitory interneurons to maintain functional network activity.
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Affiliation(s)
- Annika Mehr
- Department of Functional Genomics, Institute of Pharmacy and Molecular Biotechnology (IPMB), University of Heidelberg, 69120 Heidelberg, Germany
| | - Meike Hick
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe-University, 60590 Frankfurt am Main, Germany
| | - Susann Ludewig
- Division of Cellular Neurobiology, Zoological Institute, Technische Universität Braunschweig, 38106 Braunschweig, Germany
| | - Michaela Müller
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Ulrike Herrmann
- Division of Cellular Neurobiology, Zoological Institute, Technische Universität Braunschweig, 38106 Braunschweig, Germany
| | - Jakob von Engelhardt
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - David P Wolfer
- Institute of Anatomy, University of Zürich, 8057 Zürich, Switzerland.,Institute of Human Movement Sciences and Sport, ETH Zürich, 8057 Zürich, Switzerland
| | - Martin Korte
- Division of Cellular Neurobiology, Zoological Institute, Technische Universität Braunschweig, 38106 Braunschweig, Germany.,AG Neuroinflammation and Neurodegeneration, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Ulrike C Müller
- Department of Functional Genomics, Institute of Pharmacy and Molecular Biotechnology (IPMB), University of Heidelberg, 69120 Heidelberg, Germany.,Division of Cellular Neurobiology, Zoological Institute, Technische Universität Braunschweig, 38106 Braunschweig, Germany
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13
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Chen X, Wang D, Kegel M, von Engelhardt J. Electrophysiological Investigations of Retinogeniculate and Corticogeniculate Synapse Function. J Vis Exp 2019. [PMID: 31449246 DOI: 10.3791/59680] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The lateral geniculate nucleus is the first relay station for the visual information. Relay neurons of this thalamic nucleus integrate input from retinal ganglion cells and project it to the visual cortex. In addition, relay neurons receive top-down excitation from the cortex. The two main excitatory inputs to the relay neurons differ in several aspects. Each relay neuron receives input from only a few retinogeniculate synapses, which are large terminals with many release sites. This is reflected by the comparably strong excitation, the relay neurons receive, from retinal ganglion cells. Corticogeniculate synapses, in contrast, are simpler with few release sites and weaker synaptic strength. The two synapses also differ in their synaptic short-term plasticity. Retinogeniculate synapses have a high release probability and consequently display a short-term depression. In contrast, corticogeniculate synapses have a low release probability. Corticogeniculate fibers traverse the reticular thalamic nuclei before entering the lateral geniculate nucleus. The different locations of the reticular thalamic nucleus (rostrally from the lateral geniculate nucleus) and optic tract (ventro-laterally from the lateral geniculate nucleus) allow stimulating corticogeniculate or retinogeniculate synapses separately with extracellular stimulation electrodes. This makes the lateral geniculate nucleus an ideal brain area where two excitatory synapses with very different properties impinging onto the same cell type, can be studied simultaneously. Here, we describe a method to investigate the recording from relay neurons and to perform detailed analysis of the retinogeniculate and corticogeniculate synapse function in acute brain slices. The article contains a step-by-step protocol for the generation of acute brain slices of the lateral geniculate nucleus and steps for recording activity from relay neurons by stimulating the optic tract and corticogeniculate fibers separately.
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Affiliation(s)
- Xufeng Chen
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz
| | - Danni Wang
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz
| | - Marcel Kegel
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz
| | - Jakob von Engelhardt
- Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz;
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14
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Müller MK, Jacobi E, Sakimura K, Malinow R, von Engelhardt J. NMDA receptors mediate synaptic depression, but not spine loss in the dentate gyrus of adult amyloid Beta (Aβ) overexpressing mice. Acta Neuropathol Commun 2018; 6:110. [PMID: 30352630 PMCID: PMC6198500 DOI: 10.1186/s40478-018-0611-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 09/29/2018] [Indexed: 11/25/2022] Open
Abstract
Amyloid beta (Aβ)-mediated synapse dysfunction and spine loss are considered to be early events in Alzheimer’s disease (AD) pathogenesis. N-methyl-D-aspartate receptors (NMDARs) have previously been suggested to play a role for Amyloid beta (Aβ) toxicity. Pharmacological block of NMDAR subunits in cultured neurons and mice suggested that NMDARs containing the GluN2B subunit are necessary for Aβ-mediated changes in synapse number and function in hippocampal neurons. Interestingly, NMDARs undergo a developmental switch from GluN2B- to GluN2A-containing receptors. This indicates different functional roles of NMDARs in young mice compared to older animals. In addition, the lack of pharmacological tools to efficiently dissect the role of NMDARs containing the different subunits complicates the interpretation of their specific role. In order to address this problem and to investigate the specific role for Aβ toxicity of the distinct NMDAR subunits in dentate gyrus granule cells of adult mice, we used conditional knockout mouse lines for the subunits GluN1, GluN2A and GluN2B. Aβ-mediated changes in synaptic function and neuronal anatomy were investigated in several-months old mice with virus-mediated overproduction of Aβ and in 1-year old 5xFAD mice. We found that all three NMDAR subunits contribute to the Aβ-mediated decrease in the number of functional synapses. However, NMDARs are not required for the spine number reduction in dentate gyrus granule cells after chronic Aβ-overproduction in 5xFAD mice. Furthermore, the amplitude of synaptic and extrasynaptic NMDAR-mediated currents was reduced in dentate gyrus granule of 5xFAD mice without changes in current kinetics, suggesting that a redistribution or change in subunit composition of NMDARs does not play a role in mediating Amyloid beta (Aβ) toxicity. Our study indicates that NMDARs are involved in AD pathogenesis by compromising synapse function but not by affecting neuron morphology.
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15
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Farrow P, Khodosevich K, Sapir Y, Schulmann A, Aslam M, Stern-Bach Y, Monyer H, von Engelhardt J. Correction: Auxiliary subunits of the CKAMP family differentially modulate AMPA receptor properties. eLife 2018; 7:42543. [PMID: 30306889 PMCID: PMC6181561 DOI: 10.7554/elife.42543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 10/03/2018] [Indexed: 11/20/2022] Open
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16
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Jacobi E, von Engelhardt J. AMPA receptor complex constituents: Control of receptor assembly, membrane trafficking and subcellular localization. Mol Cell Neurosci 2018; 91:67-75. [DOI: 10.1016/j.mcn.2018.05.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 05/15/2018] [Accepted: 05/24/2018] [Indexed: 11/29/2022] Open
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17
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Chen S, Tisch N, Kegel M, Yerbes R, Hermann R, Hudalla H, Zuliani C, Gülcüler GS, Zwadlo K, von Engelhardt J, Ruiz de Almodóvar C, Martin-Villalba A. CNS Macrophages Control Neurovascular Development via CD95L. Cell Rep 2018; 19:1378-1393. [PMID: 28514658 DOI: 10.1016/j.celrep.2017.04.056] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 04/04/2017] [Accepted: 04/19/2017] [Indexed: 12/12/2022] Open
Abstract
The development of neurons and vessels shares striking anatomical and molecular features, and it is presumably orchestrated by an overlapping repertoire of extracellular signals. CNS macrophages have been implicated in various developmental functions, including the morphogenesis of neurons and vessels. However, whether CNS macrophages can coordinately influence neurovascular development and the identity of the signals involved therein is unclear. Here, we demonstrate that activity of the cell surface receptor CD95 regulates neuronal and vascular morphogenesis in the post-natal brain and retina. Furthermore, we identify CNS macrophages as the main source of CD95L, and macrophage-specific deletion thereof reduces both neurovascular complexity and synaptic activity in the brain. CD95L-induced neuronal and vascular growth is mediated through src-family kinase (SFK) and PI3K signaling. Together, our study highlights a coordinated neurovascular development instructed by CNS macrophage-derived CD95L, and it underlines the importance of macrophages for the establishment of the neurovascular network during CNS development.
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Affiliation(s)
- Si Chen
- Department of Molecular Neurobiology, German Cancer Research Center (DFKZ), 69120 Heidelberg, Germany
| | - Nathalie Tisch
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany
| | - Marcel Kegel
- Institute of Pathophysiology, University Medical Center of Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | - Rosario Yerbes
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany
| | - Robert Hermann
- Department of Molecular Neurobiology, German Cancer Research Center (DFKZ), 69120 Heidelberg, Germany
| | - Hannes Hudalla
- Department of Molecular Neurobiology, German Cancer Research Center (DFKZ), 69120 Heidelberg, Germany
| | - Cecilia Zuliani
- Department of Molecular Neurobiology, German Cancer Research Center (DFKZ), 69120 Heidelberg, Germany
| | - Gülce Sila Gülcüler
- Department of Molecular Neurobiology, German Cancer Research Center (DFKZ), 69120 Heidelberg, Germany
| | - Klara Zwadlo
- Department of Molecular Neurobiology, German Cancer Research Center (DFKZ), 69120 Heidelberg, Germany
| | - Jakob von Engelhardt
- Institute of Pathophysiology, University Medical Center of Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | | | - Ana Martin-Villalba
- Department of Molecular Neurobiology, German Cancer Research Center (DFKZ), 69120 Heidelberg, Germany.
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18
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Anwarullah, Aslam M, Badshah M, Abbasi R, Sultan A, Khan K, Ahmad N, von Engelhardt J. Further evidence for the association of CYP2D6*4 gene polymorphism with Parkinson's disease: a case control study. Genes Environ 2017; 39:18. [PMID: 28680508 PMCID: PMC5493842 DOI: 10.1186/s41021-017-0078-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 04/17/2017] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Genetic and environmental risk factors play an important role for the susceptibility to sporadic Parkinson's disease (PD). It was hypothesized that a splice variant of the CYP2D6 gene (CYP2D6*4 allele) is associated with PD because it alters the ability to metabolize toxins and in particular neurotoxins. CYP2D6 codes for the drug metabolizing enzyme debrisoquine 4-hydroxylase. The CYP2D6*4 variant results in an undetectable enzyme activity and consequently in a reduction in metabolism of some toxins. METHODS Some of agricultural chemicals have neurotoxic potential and CYP2D6 is involved in their detoxification. Thus, we conducted a case control study to investigate the association of the CYP2D6*4 with PD in a Pakistani subpopulation that is known to be exposed to high levels of some agricultural pesticides, insecticides and herbicides. RESULTS We found a significantly higher allele and genotype frequency of the CYP2D6*4 variant in 174 sporadic PD patients when compared to 200 controls. In addition, there was a trend to an earlier age of PD onset and a tremor dominant phenotype in CYP2D6*4 variant carriers. CONCLUSION Our data provide further evidence that a poor metabolizer status may increase the risk to develop PD especially in populations that are exposed to environmental toxins.
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Affiliation(s)
- Anwarullah
- Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Department of Biochemistry, Quaid-i-Azam University, Islamabad, Pakistan.,Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Muhammad Aslam
- Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
| | - Mazhar Badshah
- Department of Neurology, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Rashda Abbasi
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Aneesa Sultan
- Department of Biochemistry, Quaid-i-Azam University, Islamabad, Pakistan
| | - Kafaitullah Khan
- Department of Zoology, University of Balochistan, Quetta, Pakistan
| | - Nafees Ahmad
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Jakob von Engelhardt
- Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, 55128 Mainz, Germany
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Anwarullah A, Paramasivam N, Abbasi R, Khan K, Sultan A, Schlesner M, von Engelhardt J, Ahmad N, Aslam M. A report of whole-genome sequencing in neurologic Wilson's disease. Neurol India 2017; 65:629-631. [PMID: 28488633 DOI: 10.4103/neuroindia.ni_1274_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Anwarullah Anwarullah
- Division of Infectious and Complex Diseases, Institute of Biomedical and Genetic Engineering, Islamabad, Pakistan; Department of Biochemistry, Quaid i Azam University, Islamabad, Pakistan; Synaptic Signaling and Neurodegeneration, German Cancer Research Center, Heidelberg, Germany; Synaptic Signaling and Neurodegeneration, German Center for Neurodegenerative Diseases, Bonn, German; Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Nagarajan Paramasivam
- Division of Theoretical Bioinformatics, German Cancer Research Centre, Heidelberg; Medical faculty Heidelberg, Heidelberg University, Germany
| | - Rashda Abbasi
- Division of Infectious and Complex Diseases, Institute of Biomedical and Genetic Engineering, Islamabad, Pakistan
| | - Kafaitullah Khan
- Department of Molecular Biology, University of Baluchistan, Quetta, Pakistan
| | - Aneesa Sultan
- Department of Biochemistry, Quaid i Azam University, Islamabad, Pakistan
| | - Matthias Schlesner
- Division of Theoretical Bioinformatics, German Cancer Research Centre, Heidelberg, Germany
| | - Jakob von Engelhardt
- Synaptic Signaling and Neurodegeneration, German Cancer Research Center, Heidelberg; Synaptic Signaling and Neurodegeneration, German Center for Neurodegenerative Diseases, Bonn; Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Nafees Ahmad
- Division of Infectious and Complex Diseases, Institute of Biomedical and Genetic Engineering, Islamabad, Pakistan
| | - Muhammad Aslam
- Synaptic Signaling and Neurodegeneration, German Cancer Research Center, Heidelberg; Synaptic Signaling and Neurodegeneration, German Center for Neurodegenerative Diseases, Bonn; Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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20
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Watanabe Y, Müller MK, von Engelhardt J, Sprengel R, Seeburg PH, Monyer H. Age-Dependent Degeneration of Mature Dentate Gyrus Granule Cells Following NMDA Receptor Ablation. Front Mol Neurosci 2016; 8:87. [PMID: 26793056 PMCID: PMC4709453 DOI: 10.3389/fnmol.2015.00087] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 12/18/2015] [Indexed: 11/13/2022] Open
Abstract
N-methyl-D-aspartate receptors (NMDARs) in all hippocampal areas play an essential role in distinct processes of memory formation as well as in sustaining cell survival of postnatally generated neurons in the dentate gyrus (DG). In contrast to the beneficial effects, over-activation of NMDARs has been implicated in many acute and chronic neurological diseases, reason why therapeutic approaches and clinical trials involving receptor blockade have been envisaged for decades. Here we employed genetically engineered mice to study the long-term effect of NMDAR ablation on selective hippocampal neuronal populations. Ablation of either GluN1 or GluN2B causes degeneration of the DG. The neuronal demise affects mature neurons specifically in the dorsal DG and is NMDAR subunit-dependent. Most importantly, the degenerative process exacerbates with increasing age of the animals. These results lead us to conclude that mature granule cells in the dorsal DG undergo neurodegeneration following NMDAR ablation in aged mouse. Thus, caution needs to be exerted when considering long-term administration of NMDAR antagonists for therapeutic purposes.
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Affiliation(s)
- Yasuhito Watanabe
- Department of Clinical Neurobiology, University Hospital and German Cancer Research Center Heidelberg Heidelberg, Germany
| | - Michaela K Müller
- Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative DiseasesBonn, Germany; Synaptic Signalling and Neurodegeneration, German Cancer Research Center HeidelbergHeidelberg, Germany
| | - Jakob von Engelhardt
- Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative DiseasesBonn, Germany; Synaptic Signalling and Neurodegeneration, German Cancer Research Center HeidelbergHeidelberg, Germany
| | - Rolf Sprengel
- Department of Molecular Neurobiology, Max Planck Institute for Medical Research Heidelberg, Germany
| | - Peter H Seeburg
- Department of Molecular Neurobiology, Max Planck Institute for Medical Research Heidelberg, Germany
| | - Hannah Monyer
- Department of Clinical Neurobiology, University Hospital and German Cancer Research Center Heidelberg Heidelberg, Germany
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21
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Farrow P, Khodosevich K, Sapir Y, Schulmann A, Aslam M, Stern-Bach Y, Monyer H, von Engelhardt J. Auxiliary subunits of the CKAMP family differentially modulate AMPA receptor properties. eLife 2015; 4:e09693. [PMID: 26623514 PMCID: PMC4733035 DOI: 10.7554/elife.09693] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 11/30/2015] [Indexed: 01/01/2023] Open
Abstract
AMPA receptor (AMPAR) function is modulated by auxiliary subunits. Here, we report on three AMPAR interacting proteins—namely CKAMP39, CKAMP52 and CKAMP59—that, together with the previously characterized CKAMP44, constitute a novel family of auxiliary subunits distinct from other families of AMPAR interacting proteins. The new members of the CKAMP family display distinct regional and developmental expression profiles in the mouse brain. Notably, despite their structural similarities they exert diverse modulation on AMPAR gating by influencing deactivation, desensitization and recovery from desensitization, as well as glutamate and cyclothiazide potency to AMPARs. This study indicates that AMPAR function is very precisely controlled by the cell-type specific expression of the CKAMP family members. The brain processes and transmits information through large networks of cells called neurons. A neuron can pass the information it receives to other neurons by releasing chemicals called neurotransmitters across junctions known as synapses. These chemicals bind to receptor proteins on the surface of the neighboring neuron, which triggers changes that affect the activity of this neuron. Glutamate is the most commonly used neurotransmitter in the brain and binds to receptor proteins called AMPA receptors. If a neuron frequently sends glutamate across a particular synapse, the number of AMPA receptors in the second neuron will increase in response. This makes signaling across the synapse easier – a process known as synaptic strengthening. The ability to change the strength of synapses is important for learning and memory. Proteins called auxiliary subunits also bind to AMPA receptors and regulate their properties, and hence also affect the strength of the synapse. For instance, some auxiliary subunits increase the number of AMPA receptors at the synapse, while others have an effect on how the receptor protein works. In 2010, researchers identified a new auxiliary protein called CKAMP44 that modifies AMPA receptor activity. Now, Farrow, Khodosevich, Sapir, Schulmann et al. – including some of the researchers involved in the 2010 study – have identified three other auxiliary proteins that are similar to CKAMP44. Collectively, these four proteins are termed the CKAMP family. The sequences of all four proteins were found to share many common features, especially in the regions that bind to the AMPA receptors. Like CKAMP44, the new members of the CKAMP family are only present in the brain, although each protein is produced in different brain regions. Further investigation revealed that each member of the CKAMP family affects the AMPA receptor channels in a different way. Taken together, Farrow et al.’s results suggest that the different CKAMP family members allow the activity of the AMPA receptors to be precisely controlled. The next challenge is to understand in more detail how each CKAMP family member influences how AMPA receptors work.
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Affiliation(s)
- Paul Farrow
- Synaptic Signalling and Neurodegeneration, German Cancer Research Center, Heidelberg, Germany.,Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative Diseases, Bonn, Germany
| | - Konstantin Khodosevich
- Department of Clinical Neurobiology, Medical Faculty of Heidelberg University, Heidelberg, Germany.,German Cancer Research Center, Heidelberg, Germany
| | - Yechiam Sapir
- Department of Biochemistry and Molecular Biology, Institute for Medical Research - Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Anton Schulmann
- Department of Clinical Neurobiology, Medical Faculty of Heidelberg University, Heidelberg, Germany.,German Cancer Research Center, Heidelberg, Germany
| | - Muhammad Aslam
- Synaptic Signalling and Neurodegeneration, German Cancer Research Center, Heidelberg, Germany.,Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative Diseases, Bonn, Germany
| | - Yael Stern-Bach
- Department of Biochemistry and Molecular Biology, Institute for Medical Research - Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Hannah Monyer
- Department of Clinical Neurobiology, Medical Faculty of Heidelberg University, Heidelberg, Germany
| | - Jakob von Engelhardt
- Synaptic Signalling and Neurodegeneration, German Cancer Research Center, Heidelberg, Germany.,Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative Diseases, Bonn, Germany
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22
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Arslan A, von Engelhardt J, Wisden W. Cytoplasmic domain of δ subunit is important for the extra-synaptic targeting of GABAA receptor subtypes. J Integr Neurosci 2015; 13:617-31. [PMID: 25233879 DOI: 10.1142/s0219635214500228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
GABA(A) receptors (GABA(A)Rs) are hetero-pentameric chloride channels and the primary sites for fast synaptic inhibition. We have expressed recombinant γ2 and δ subunits of GABA(A)Rs in cultured hippocampal neurons to analyze the membrane targeting of synaptic and extra-synaptic GABA(A)Rs, a phenomenon not well understood. Our data demonstrate that the synaptic targeting of γ2-containing GABA(A)Rs (γ2-GABA(A)Rs) does not depend on the cytoplasmic loop of γ2 subunit, in parallel with previous findings, showing that the synaptic localization of γ2-GABA(A)Rs requires the TM4 domain of γ2 rather than the large cytoplasmic loop. On the other hand, we showed here that the extrasynaptic targeting of the δ-containing GABA(A)Rs (δ-GABA(A)Rs) depends on the cytoplasmic loop of δ subunit via an active or a passive mechanism. We also show that the amino acid sequences of δ loop is highly conserved across the whole span of vertebrate evolution suggesting an active role of δ loop in extra-synaptic targeting of corresponding receptor subtypes.
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Affiliation(s)
- Ayla Arslan
- Department of Clinical Neurobiology, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany , Department of Molecular Biology and Genetics, Faculty of Engineering and Natural Sciences, Üsküdar University, Altunizade Mah. Haluk Türksoy Sok. No: 14, PK 34662 Üsküdar/İstanbul, Turkey
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23
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von Engelhardt J, Bocklisch C, Tönges L, Herb A, Mishina M, Monyer H. GluN2D-containing NMDA receptors-mediate synaptic currents in hippocampal interneurons and pyramidal cells in juvenile mice. Front Cell Neurosci 2015; 9:95. [PMID: 25859181 PMCID: PMC4373385 DOI: 10.3389/fncel.2015.00095] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 03/02/2015] [Indexed: 01/15/2023] Open
Abstract
The differential regulation of the two major N-methyl-D-aspartate receptor (NMDAR) subunits GluN2A and GluN2B during development in forebrain pyramidal cells has been thoroughly investigated. In contrast, much less is known about the role of GluN2D, which is expressed at low levels and is downregulated following the second postnatal week. However, it appears that few cells, presumably interneurons, continue to express GluN2D also in juvenile mice. To investigate which hippocampal cell types express this subunit, we generated transgenic mice with EGFP-tagged GluN2D receptors. The expression of the transgene was confined to hippocampal interneurons, most of which were parvalbumin- and/or somatostatin-positive. Electrophysiological and morphological analyses showed that GluN2D was present mainly in fast spiking basket and axo-axonic cells. Based on pharmacological evidence and electrophysiological analysis of GluN2D knockout mice, we conclude that GluN2D-containing NMDARs mediate synaptic currents in hippocampal interneurons of young and juvenile mice and in CA1 pyramidal neurons of newborn mice.
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Affiliation(s)
- Jakob von Engelhardt
- Synaptic Signalling and Neurodegeneration, German Cancer Research Center (DKFZ) Heidelberg, Germany ; Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE) Bonn, Germany
| | - Christina Bocklisch
- Department of Clinical Neurobiology, Medical Faculty of Heidelberg University and DKFZ Heidelberg, Germany
| | - Lars Tönges
- Department of Clinical Neurobiology, Medical Faculty of Heidelberg University and DKFZ Heidelberg, Germany
| | - Anne Herb
- Department of Clinical Neurobiology, Medical Faculty of Heidelberg University and DKFZ Heidelberg, Germany
| | - Masayoshi Mishina
- Brain Science Laboratory, The Research Organization of Science and Technology, Ritsumeikan University Kusatsu, Shiga, Japan
| | - Hannah Monyer
- Department of Clinical Neurobiology, Medical Faculty of Heidelberg University and DKFZ Heidelberg, Germany
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24
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Schütz B, Jurastow I, Bader S, Ringer C, von Engelhardt J, Chubanov V, Gudermann T, Diener M, Kummer W, Krasteva-Christ G, Weihe E. Chemical coding and chemosensory properties of cholinergic brush cells in the mouse gastrointestinal and biliary tract. Front Physiol 2015; 6:87. [PMID: 25852573 PMCID: PMC4371653 DOI: 10.3389/fphys.2015.00087] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 03/04/2015] [Indexed: 11/13/2022] Open
Abstract
The mouse gastro-intestinal and biliary tract mucosal epithelia harbor choline acetyltransferase (ChAT)-positive brush cells with taste cell-like traits. With the aid of two transgenic mouse lines that express green fluorescent protein (EGFP) under the control of the ChAT promoter (EGFP (ChAT) ) and by using in situ hybridization and immunohistochemistry we found that EGFP (ChAT) cells were clustered in the epithelium lining the gastric groove. EGFP (ChAT) cells were numerous in the gall bladder and bile duct, and found scattered as solitary cells along the small and large intestine. While all EGFP (ChAT) cells were also ChAT-positive, expression of the high-affinity choline transporter (ChT1) was never detected. Except for the proximal colon, EGFP (ChAT) cells also lacked detectable expression of the vesicular acetylcholine transporter (VAChT). EGFP (ChAT) cells were found to be separate from enteroendocrine cells, however they were all immunoreactive for cytokeratin 18 (CK18), transient receptor potential melastatin-like subtype 5 channel (TRPM5), and for cyclooxygenases 1 (COX1) and 2 (COX2). The ex vivo stimulation of colonic EGFP (ChAT) cells with the bitter substance denatonium resulted in a strong increase in intracellular calcium, while in other epithelial cells such an increase was significantly weaker and also timely delayed. Subsequent stimulation with cycloheximide was ineffective in both cell populations. Given their chemical coding and chemosensory properties, EGFP (ChAT) brush cells thus may have integrative functions and participate in induction of protective reflexes and inflammatory events by utilizing ACh and prostaglandins for paracrine signaling.
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Affiliation(s)
- Burkhard Schütz
- Department of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps-University Marburg, Germany
| | - Innokentij Jurastow
- Institute of Anatomy and Cell Biology, Justus-Liebig-University Giessen, Germany
| | - Sandra Bader
- Institute of Veterinary Physiology and Biochemistry, Justus-Liebig-University Giessen, Germany
| | - Cornelia Ringer
- Department of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps-University Marburg, Germany
| | - Jakob von Engelhardt
- Synaptic Signaling and Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE) Bonn, Germany ; German Cancer Research Center (DKFZ) Heidelberg, Germany
| | - Vladimir Chubanov
- Walther-Straub-Institute for Pharmacology and Toxicology, Ludwig-Maximilians-University Munich, Germany
| | - Thomas Gudermann
- Walther-Straub-Institute for Pharmacology and Toxicology, Ludwig-Maximilians-University Munich, Germany
| | - Martin Diener
- Institute of Veterinary Physiology and Biochemistry, Justus-Liebig-University Giessen, Germany
| | - Wolfgang Kummer
- Institute of Anatomy and Cell Biology, Justus-Liebig-University Giessen, Germany
| | - Gabriela Krasteva-Christ
- Institute of Anatomy and Cell Biology, Justus-Liebig-University Giessen, Germany ; Institute of Anatomy and Cell Biology, Julius-Maximilians-University Würzburg, Germany
| | - Eberhard Weihe
- Department of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps-University Marburg, Germany
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Khodosevich K, Jacobi E, Farrow P, Schulmann A, Rusu A, Zhang L, Sprengel R, Monyer H, von Engelhardt J. Coexpressed auxiliary subunits exhibit distinct modulatory profiles on AMPA receptor function. Neuron 2014; 83:601-15. [PMID: 25066086 DOI: 10.1016/j.neuron.2014.07.004] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2014] [Indexed: 01/30/2023]
Abstract
Gating properties and surface trafficking of AMPA receptors (AMPARs) are modulated by auxiliary subunits. Here we studied the function of coexpressed auxiliary subunits belonging to two different classes. We focused on TARP γ-8 and CKAMP44 in dentate gyrus (DG) granule cells, since both subunits are highly expressed in this cell type. TARP γ-8 and CKAMP44 decrease the rate of deactivation but have an opposing influence on receptor desensitization, which accounts for their differential modulation of synaptic short-term plasticity. Furthermore, long-term plasticity (LTP) requires TARP γ-8 but not CKAMP44. The coexpression of both auxiliary subunits is necessary for the efficient targeting of AMPARs to the cell surface of DG granule cells. Finally, electrophysiological and biochemical evidence support the notion that CKAMP44 and TARP γ-8 can be contained in the same AMPAR complex.
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Affiliation(s)
- Konstantin Khodosevich
- Department of Clinical Neurobiology, University Hospital and DKFZ Heidelberg, 69120 Heidelberg, Germany
| | - Eric Jacobi
- Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), 53175 Bonn, Germany; Synaptic Signalling and Neurodegeneration, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Paul Farrow
- Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), 53175 Bonn, Germany; Synaptic Signalling and Neurodegeneration, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Anton Schulmann
- Department of Clinical Neurobiology, University Hospital and DKFZ Heidelberg, 69120 Heidelberg, Germany
| | - Alexandru Rusu
- Department of Clinical Neurobiology, University Hospital and DKFZ Heidelberg, 69120 Heidelberg, Germany
| | - Ling Zhang
- Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Rolf Sprengel
- Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Hannah Monyer
- Department of Clinical Neurobiology, University Hospital and DKFZ Heidelberg, 69120 Heidelberg, Germany
| | - Jakob von Engelhardt
- Synaptic Signalling and Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), 53175 Bonn, Germany; Synaptic Signalling and Neurodegeneration, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany.
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26
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Khodosevich K, Lazarini F, von Engelhardt J, Kaneko H, Lledo PM, Monyer H. Connective tissue growth factor regulates interneuron survival and information processing in the olfactory bulb. Neuron 2013; 79:1136-51. [PMID: 23993699 DOI: 10.1016/j.neuron.2013.07.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/11/2013] [Indexed: 12/27/2022]
Abstract
Neurogenesis underlies plastic changes in defined neuronal circuits in the postnatal and adult brain. Here we identify connective tissue growth factor (CTGF) as a critical factor in the mouse olfactory bulb (OB) in determining the efficiency of incorporation of postnatally born inhibitory neurons, thus gating the output of glomeruli, the first relay station of olfactory processing in the brain. In the OB, CTGF expression was restricted to prenatally born external tufted cells. CTGF enhanced the proapoptotic activity of glial-derived TGF-β2, decreasing the survival of periglomerular inhibitory neurons. Changes in CTGF expression levels in the OB led to modifications in local neuronal circuitry and olfactory behaviors. We show that the odorant-specific recruitment of distinct glomeruli resulted in enhanced local CTGF expression levels in the activated glomeruli. Collectively our data reveal a molecular mechanism controlling the survival of defined postnatally born neurons, thus adapting neuronal integration to the sensory experiences.
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Affiliation(s)
- Konstantin Khodosevich
- Department of Clinical Neurobiology, Heidelberg University Medical Center, 69120 Heidelberg, Germany; Department of Clinical Neurobiology/A230, German Center for Cancer Research (DKFZ), 69120 Heidelberg, Germany
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27
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Korotkova T, Fuchs EC, Ponomarenko A, von Engelhardt J, Monyer H. NMDA receptor ablation on parvalbumin-positive interneurons impairs hippocampal synchrony, spatial representations, and working memory. Neuron 2010; 68:557-69. [PMID: 21040854 DOI: 10.1016/j.neuron.2010.09.017] [Citation(s) in RCA: 366] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2010] [Indexed: 01/17/2023]
Abstract
Activity of parvalbumin-positive hippocampal interneurons is critical for network synchronization but the receptors involved therein have remained largely unknown. Here we report network and behavioral deficits in mice with selective ablation of NMDA receptors in parvalbumin-positive interneurons (NR1(PVCre-/-)). Recordings of local field potentials and unitary neuronal activity in the hippocampal CA1 area revealed altered theta oscillations (5-10 Hz) in freely behaving NR1(PVCre-/-) mice. Moreover, in contrast to controls, in NR1(PVCre-/-) mice the remaining theta rhythm was abolished by the administration of atropine. Gamma oscillations (35-85 Hz) were increased and less modulated by the concurrent theta rhythm in the mutant. Positional firing of pyramidal cells in NR1(PVCre-/-) mice was less spatially and temporally precise. Finally, NR1(PVCre-/-) mice exhibited impaired spatial working as well as spatial short- and long-term recognition memory but showed no deficits in open field exploratory activity and spatial reference learning.
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Affiliation(s)
- Tatiana Korotkova
- Department of Clinical Neurobiology, IZN, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
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28
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von Engelhardt J, Mack V, Sprengel R, Kavenstock N, Li KW, Stern-Bach Y, Smit AB, Seeburg PH, Monyer H. CKAMP44: A Brain-Specific Protein Attenuating Short-Term Synaptic Plasticity in the Dentate Gyrus. Science 2010; 327:1518-22. [DOI: 10.1126/science.1184178] [Citation(s) in RCA: 210] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Jakob von Engelhardt
- Department of Clinical Neurobiology, University of Heidelberg, 6910 Heidelberg, Germany
| | - Volker Mack
- Department of Clinical Neurobiology, University of Heidelberg, 6910 Heidelberg, Germany
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit, 1081 HV Amsterdam, the Netherlands
| | - Rolf Sprengel
- Department of Molecular Neurobiology, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Netta Kavenstock
- Department of Biochemistry and Molecular Biology, Institute for Medical Research Israel-Canada (IMRIC), the Hebrew University–Hadassah Medical School, Jerusalem 91120, Israel
| | - Ka Wan Li
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit, 1081 HV Amsterdam, the Netherlands
| | - Yael Stern-Bach
- Department of Biochemistry and Molecular Biology, Institute for Medical Research Israel-Canada (IMRIC), the Hebrew University–Hadassah Medical School, Jerusalem 91120, Israel
| | - August B. Smit
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit, 1081 HV Amsterdam, the Netherlands
| | - Peter H. Seeburg
- Department of Molecular Neurobiology, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Hannah Monyer
- Department of Clinical Neurobiology, University of Heidelberg, 6910 Heidelberg, Germany
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von Engelhardt J, Doganci B, Seeburg PH, Monyer H. Synaptic NR2A- but not NR2B-Containing NMDA Receptors Increase with Blockade of Ionotropic Glutamate Receptors. Front Mol Neurosci 2009; 2:19. [PMID: 19893758 PMCID: PMC2773170 DOI: 10.3389/neuro.02.019.2009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Accepted: 10/01/2009] [Indexed: 11/16/2022] Open
Abstract
NMDA receptors (NMDAR) are key molecules involved in physiological and pathophysiological brain processes such as plasticity and excitotoxicity. Neuronal activity regulates NMDA receptor levels in the cell membrane. However, little is known on which time scale this regulation occurs and whether the two main diheteromeric NMDA receptor subtypes in forebrain, NR1/NR2A and NR1/NR2B, are regulated in a similar fashion. As these differ considerably in their electrophysiological properties, the NR2A/NR2B ratio affects the neurons’ reaction to NMDA receptor activation. Here we provide evidence that the basal turnover rate in the cell membrane of NR2A- and NR2B-containing receptors is comparable. However, the level of the NR2A subtype in the cell membrane is highly regulated by NMDA receptor activity, resulting in a several-fold increased insertion of new receptors after blocking NMDAR for 8 h. Blocking AMPA receptors also increases the delivery of NR2A-containing receptors to the cell membrane. In contrast, the amount of NR2B-containing receptors in the cell membrane is not affected by ionotropic glutamate receptor block. Moreover, electrophysiological analysis of synaptic currents in hippocampal cultures and CA1 neurons of hippocampal slices revealed that after 8 h of NMDA receptor blockade the NMDA EPSCs increase as a result of augmented NMDA receptor-mediated currents. In conclusion, synaptic NR2A- but not NR2B-containing receptors are dynamically regulated, enabling neurons to change their NR2A/NR2B ratio within a time scale of hours.
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Affiliation(s)
- Jakob von Engelhardt
- Department of Clinical Neurobiology, University of Heidelberg Heidelberg, Germany
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30
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Abstract
Acetylcholine is a major neurotransmitter that modulates cortical functions. In addition to basal forebrain neurons that give rise to the principal cholinergic input into the cortex, a second source constituted by intrinsic cholinergic interneurons has been identified. Although these cells have been characterized anatomically, little is known about their functional role in cortical microcircuits. The paucity of this cell population has been a major hindrance for detailed electrophysiological investigations. To facilitate functional studies, we generated transgenic mice that express enhanced green fluorescent protein (EGFP) in choline acetyltransferase (ChAT)-positive neurons. Aided by the transgene expression, the characterization of distinct cholinergic interneurons was possible. These cells were located in layer 2-3, had a bipolar morphology, were calretinin- and vasoactive intestinal peptide positive, but had a non-GABAergic phenotype. Paired recordings showed that EGFP/ChAT-positive neurons receive excitatory and inhibitory input from adjacent principal cells and various types of interneurons. However, EGFP/ChAT-positive neurons do not exert direct postsynaptic responses in neighboring neurons. Interestingly, prolonged activation of EGFP-labeled cholinergic neurons induces an increase in spontaneous EPSCs in adjacent pyramidal neurons. This indirect effect is mediated by nicotinic receptors that are presumably presynaptically localized. Thus, intrinsic bipolar cholinergic neurons can modulate cortical function locally.
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Affiliation(s)
- Jakob von Engelhardt
- Department Clinical Neurobiology, University of Heidelberg, 69120 Heidelberg, Germany
| | - Marina Eliava
- Department of Physiology, Northwestern University, Chicago, Illinois 60611, and
| | - Axel H. Meyer
- Neuroscience Research, Abbott GmbH and Company KG, 67061 Ludwigshafen, Germany
| | - Andrei Rozov
- Department Clinical Neurobiology, University of Heidelberg, 69120 Heidelberg, Germany
| | - Hannah Monyer
- Department Clinical Neurobiology, University of Heidelberg, 69120 Heidelberg, Germany
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von Engelhardt J, Coserea I, Pawlak V, Fuchs EC, Köhr G, Seeburg PH, Monyer H. Excitotoxicity in vitro by NR2A- and NR2B-containing NMDA receptors. Neuropharmacology 2007; 53:10-7. [PMID: 17570444 DOI: 10.1016/j.neuropharm.2007.04.015] [Citation(s) in RCA: 113] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2006] [Revised: 03/24/2007] [Accepted: 04/04/2007] [Indexed: 11/24/2022]
Abstract
Excitotoxicity, exacerbating acute brain damage from brain trauma or stroke, is mediated in part by excessive Ca(2+)-influx from prolonged NMDA receptor activation. However, the contribution to excitotoxicity by each of the main NMDAR subtypes in glutamatergic forebrain neurons, the NR2A- and NR2B-types, has remained enigmatic. Here, we investigated this issue by use of pharmacological and genetic tools in cultured cortical neurons. In wild-type neurons the contribution of the NMDA receptor subtypes to excitotoxicity changed with the age of the cultures. The blockade of NR2B-containing NMDA receptors prevented NMDA-mediated toxicity in young cultures after 14days in vitro (DIV14), but both subtypes triggered excitotoxicity in older (DIV21) cultures. Notably, blocking either of the two subtypes failed to prevent NMDA-elicited cell death, indicating that the remaining subtype triggers cell demise. Intriguingly, a neuroprotective aspect of the NR2A subtype became apparent at submaximal NMDA concentration only at DIV21. The NR2A subtype mediated NMDA toxicity as well as partial protection only if it carried a functional C-terminal domain. Upon deletion of this domain in the NR2A subtype, excitotoxicity was mediated entirely via the NR2B subtype, both at DIV14 and DIV21. Our findings predict that successful therapeutic intervention in stroke based on currently available NMDA receptor subtype-selective blockers is unlikely.
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Affiliation(s)
- Jakob von Engelhardt
- IZN and Department of Clinical Neurobiology, University Hospital of Neurology, INF 364, 69120 Heidelberg, Germany
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