1
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Ng AN, Salter EW, Georgiou J, Bortolotto ZA, Collingridge GL. Amyloid-β 1-42 oligomers enhance mGlu 5R-dependent synaptic weakening via NMDAR activation and complement C5aR1 signaling. iScience 2023; 26:108412. [PMID: 38053635 PMCID: PMC10694656 DOI: 10.1016/j.isci.2023.108412] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/13/2023] [Accepted: 11/03/2023] [Indexed: 12/07/2023] Open
Abstract
Synaptic weakening and loss are well-correlated with the pathology of Alzheimer's disease (AD). Oligomeric amyloid beta (oAβ) is considered a major synaptotoxic trigger for AD. Recent studies have implicated hyperactivation of the complement cascade as the driving force for loss of synapses caused by oAβ. However, the initial synaptic cues that trigger pathological complement activity remain elusive. Here, we examined a form of synaptic long-term depression (LTD) mediated by metabotropic glutamate receptors (mGluRs) that is disrupted in rodent models of AD. Exogenous application of oAβ (1-42) to mouse hippocampal slices enhanced the magnitude of mGlu subtype 5 receptor (mGlu5R)-dependent LTD. We found that the enhanced synaptic weakening occurred via both N-methyl-D-aspartate receptors (NMDARs) and complement C5aR1 signaling. Our findings reveal a mechanistic interaction between mGlu5R, NMDARs, and the complement system in aberrant synaptic weakening induced by oAβ, which could represent an early trigger of synaptic loss and degeneration in AD.
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Affiliation(s)
- Ai Na Ng
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Eric W. Salter
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - John Georgiou
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Tower, 60 Leonard Avenue, Toronto, ON M5T 0S8, Canada
| | - Zuner A. Bortolotto
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Graham L. Collingridge
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, 600 University Avenue, Toronto, ON M5G 1X5, Canada
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Tower, 60 Leonard Avenue, Toronto, ON M5T 0S8, Canada
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2
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Grochowska KM, Gomes GM, Raman R, Kaushik R, Sosulina L, Kaneko H, Oelschlegel AM, Yuanxiang P, Reyes‐Resina I, Bayraktar G, Samer S, Spilker C, Woo MS, Morawski M, Goldschmidt J, Friese MA, Rossner S, Navarro G, Remy S, Reissner C, Karpova A, Kreutz MR. Jacob-induced transcriptional inactivation of CREB promotes Aβ-induced synapse loss in Alzheimer's disease. EMBO J 2023; 42:e112453. [PMID: 36594364 PMCID: PMC9929644 DOI: 10.15252/embj.2022112453] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 12/07/2022] [Accepted: 12/09/2022] [Indexed: 01/04/2023] Open
Abstract
Synaptic dysfunction caused by soluble β-amyloid peptide (Aβ) is a hallmark of early-stage Alzheimer's disease (AD), and is tightly linked to cognitive decline. By yet unknown mechanisms, Aβ suppresses the transcriptional activity of cAMP-responsive element-binding protein (CREB), a master regulator of cell survival and plasticity-related gene expression. Here, we report that Aβ elicits nucleocytoplasmic trafficking of Jacob, a protein that connects a NMDA-receptor-derived signalosome to CREB, in AD patient brains and mouse hippocampal neurons. Aβ-regulated trafficking of Jacob induces transcriptional inactivation of CREB leading to impairment and loss of synapses in mouse models of AD. The small chemical compound Nitarsone selectively hinders the assembly of a Jacob/LIM-only 4 (LMO4)/ Protein phosphatase 1 (PP1) signalosome and thereby restores CREB transcriptional activity. Nitarsone prevents impairment of synaptic plasticity as well as cognitive decline in mouse models of AD. Collectively, the data suggest targeting Jacob protein-induced CREB shutoff as a therapeutic avenue against early synaptic dysfunction in AD.
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Affiliation(s)
- Katarzyna M Grochowska
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
- Leibniz Group ‘Dendritic Organelles and Synaptic Function’, Center for Molecular Neurobiology (ZMNH)University Medical Center Hamburg‐EppendorfHamburgGermany
| | - Guilherme M Gomes
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
- Center for Behavioral Brain SciencesOtto von Guericke UniversityMagdeburgGermany
| | - Rajeev Raman
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Rahul Kaushik
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Liudmila Sosulina
- Department of Cellular NeuroscienceLeibniz Institute for NeurobiologyMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
| | - Hiroshi Kaneko
- Department of Cellular NeuroscienceLeibniz Institute for NeurobiologyMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
| | | | - PingAn Yuanxiang
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | | | - Gonca Bayraktar
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Sebastian Samer
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Christina Spilker
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Marcel S Woo
- Institute of Neuroimmunology and Multiple Sclerosis, Center for Molecular Neurobiology (ZMNH)University Medical Center Hamburg‐EppendorfHamburgGermany
| | - Markus Morawski
- Molecular Imaging in NeurosciencesPaul Flechsig Institute of Brain ResearchLeipzigGermany
| | - Jürgen Goldschmidt
- Department of Systems Physiology of Learning and MemoryLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Manuel A Friese
- Institute of Neuroimmunology and Multiple Sclerosis, Center for Molecular Neurobiology (ZMNH)University Medical Center Hamburg‐EppendorfHamburgGermany
| | - Steffen Rossner
- Molecular Imaging in NeurosciencesPaul Flechsig Institute of Brain ResearchLeipzigGermany
| | - Gemma Navarro
- Department of Biochemistry and Physiology, Faculty of Pharmacy and Food ScienceUniversity of BarcelonaBarcelonaSpain
- Institut de Neurociències de la Universitat de BarcelonaBarcelonaSpain
| | - Stefan Remy
- Center for Behavioral Brain SciencesOtto von Guericke UniversityMagdeburgGermany
- Department of Cellular NeuroscienceLeibniz Institute for NeurobiologyMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
| | - Carsten Reissner
- Institute of Anatomy and Molecular NeurobiologyWestfälische Wilhelms‐UniversityMünsterGermany
| | - Anna Karpova
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
- Center for Behavioral Brain SciencesOtto von Guericke UniversityMagdeburgGermany
| | - Michael R Kreutz
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
- Leibniz Group ‘Dendritic Organelles and Synaptic Function’, Center for Molecular Neurobiology (ZMNH)University Medical Center Hamburg‐EppendorfHamburgGermany
- Center for Behavioral Brain SciencesOtto von Guericke UniversityMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
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3
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Ghatak S, Nakamura T, Lipton SA. Aberrant protein S-nitrosylation contributes to hyperexcitability-induced synaptic damage in Alzheimer's disease: Mechanistic insights and potential therapies. Front Neural Circuits 2023; 17:1099467. [PMID: 36817649 PMCID: PMC9932935 DOI: 10.3389/fncir.2023.1099467] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 01/18/2023] [Indexed: 02/05/2023] Open
Abstract
Alzheimer's disease (AD) is arguably the most common cause of dementia in the elderly and is marked by progressive synaptic degeneration, which in turn leads to cognitive decline. Studies in patients and in various AD models have shown that one of the early signatures of AD is neuronal hyperactivity. This excessive electrical activity contributes to dysregulated neural network function and synaptic damage. Mechanistically, evidence suggests that hyperexcitability accelerates production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) that contribute to neural network impairment and synapse loss. This review focuses on the pathways and molecular changes that cause hyperexcitability and how RNS-dependent posttranslational modifications, represented predominantly by protein S-nitrosylation, mediate, at least in part, the deleterious effects of hyperexcitability on single neurons and the neural network, resulting in synaptic loss in AD.
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Affiliation(s)
- Swagata Ghatak
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India
| | - Tomohiro Nakamura
- Neurodegeneration New Medicines Center and Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States,*Correspondence: Tomohiro Nakamura,
| | - Stuart A. Lipton
- Neurodegeneration New Medicines Center and Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States,Department of Neurosciences, School of Medicine, University of California, San Diego, La Jolla, CA, United States,Stuart A. Lipton,
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4
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Taylor AP, Davis PJ, Aubrey LD, White JBR, Parton ZN, Staniforth RA. Simple, Reliable Protocol for High-Yield Solubilization of Seedless Amyloid-β Monomer. ACS Chem Neurosci 2022; 14:53-71. [PMID: 36512740 PMCID: PMC9817077 DOI: 10.1021/acschemneuro.2c00411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Self-assembly of the amyloid-β (Aβ) peptide to form toxic oligomers and fibrils is a key causal event in the onset of Alzheimer's disease, and Aβ is the focus of intense research in neuroscience, biophysics, and structural biology aimed at therapeutic development. Due to its rapid self-assembly and extreme sensitivity to aggregation conditions, preparation of seedless, reproducible Aβ solutions is highly challenging, and there are serious ongoing issues with consistency in the literature. In this paper, we use a liquid-phase separation technique, asymmetric flow field-flow fractionation with multiangle light scattering (AF4-MALS), to develop and validate a simple, effective, economical method for re-solubilization and quality control of purified, lyophilized Aβ samples. Our findings were obtained with recombinant peptide but are physicochemical in nature and thus highly relevant to synthetic peptide. We show that much of the variability in the literature stems from the inability of overly mild solvent treatments to produce consistently monomeric preparations and is rectified by a protocol involving high-pH (>12) dissolution, sonication, and rapid freezing to prevent modification. Aβ treated in this manner is chemically stable, can be stored over long timescales at -80 °C, and exhibits remarkably consistent self-assembly behavior when returned to near-neutral pH. These preparations are highly monomeric, seedless, and do not require additional rounds of size exclusion, eliminating the need for this costly procedure and increasing the flexibility of use. We propose that our improved protocol is the simplest, fastest, and most effective way to solubilize Aβ from diverse sources for sensitive self-assembly and toxicity assays.
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5
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Hu Z, Ondrejcak T, Yu P, Zhang Y, Yang Y, Klyubin I, Kennelly SP, Rowan MJ, Hu NW. Do tau-synaptic long-term depression interactions in the hippocampus play a pivotal role in the progression of Alzheimer's disease? Neural Regen Res 2022; 18:1213-1219. [PMID: 36453396 PMCID: PMC9838152 DOI: 10.4103/1673-5374.360166] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Cognitive decline in Alzheimer's disease correlates with the extent of tau pathology, in particular tau hyperphosphorylation that initially appears in the transentorhinal and related regions of the brain including the hippocampus. Recent evidence indicates that tau hyperphosphorylation caused by either amyloid-β or long-term depression, a form of synaptic weakening involved in learning and memory, share similar mechanisms. Studies from our group and others demonstrate that long-term depression-inducing low-frequency stimulation triggers tau phosphorylation at different residues in the hippocampus under different experimental conditions including aging. Conversely, certain forms of long-term depression at hippocampal glutamatergic synapses require endogenous tau, in particular, phosphorylation at residue Ser396. Elucidating the exact mechanisms of interaction between tau and long-term depression may help our understanding of the physiological and pathological functions of tau/tau (hyper)phosphorylation. We first summarize experimental evidence regarding tau-long-term depression interactions, followed by a discussion of possible mechanisms by which this interplay may influence the pathogenesis of Alzheimer's disease. Finally, we conclude with some thoughts and perspectives on future research about these interactions.
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Affiliation(s)
- Zhengtao Hu
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan Province, China,Department of Gerontology, The First Affiliated Hospital of Wannan Medical College, Wuhu, Anhui Province, China
| | - Tomas Ondrejcak
- Department of Pharmacology & Therapeutics and Institute of Neuroscience, Trinity College, Dublin, Ireland
| | - Pengpeng Yu
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan Province, China
| | - Yangyang Zhang
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan Province, China
| | - Yin Yang
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan Province, China,Department of Pharmacology & Therapeutics and Institute of Neuroscience, Trinity College, Dublin, Ireland
| | - Igor Klyubin
- Department of Pharmacology & Therapeutics and Institute of Neuroscience, Trinity College, Dublin, Ireland
| | - Sean P. Kennelly
- Department of Age-Related Healthcare, Tallaght University Hospital, Dublin, Ireland,Department of Medical Gerontology, Trinity College, Dublin, Ireland
| | - Michael J. Rowan
- Department of Pharmacology & Therapeutics and Institute of Neuroscience, Trinity College, Dublin, Ireland
| | - Neng-Wei Hu
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan Province, China,Department of Pharmacology & Therapeutics and Institute of Neuroscience, Trinity College, Dublin, Ireland,Correspondence to: Neng-Wei Hu, .
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6
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Forest KH, Taketa R, Arora K, Todorovic C, Nichols RA. The Neuroprotective Beta Amyloid Hexapeptide Core Reverses Deficits in Synaptic Plasticity in the 5xFAD APP/PS1 Mouse Model. Front Mol Neurosci 2021; 14:576038. [PMID: 33912008 PMCID: PMC8075567 DOI: 10.3389/fnmol.2021.576038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 03/11/2021] [Indexed: 11/16/2022] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia in the aging population. Evidence implicates elevated soluble oligomeric Aβ as one of the primary triggers during the prodromic phase leading to AD, effected largely via hyperphosphorylation of the microtubule-associated protein tau. At low, physiological levels (pM-nM), however, oligomeric Aβ has been found to regulate synaptic plasticity as a neuromodulator. Through mutational analysis, we found a core hexapeptide sequence within the N-terminal domain of Aβ (N-Aβcore) accounting for its physiological activity, and subsequently found that the N-Aβcore peptide is neuroprotective. Here, we characterized the neuroprotective potential of the N-Aβcore against dysfunction of synaptic plasticity assessed in ex vivo hippocampal slices from 5xFAD APP/PS1 mice, specifically hippocampal long-term potentiation (LTP) and long-term depression (LTD). The N-Aβcore was shown to reverse impairment in synaptic plasticity in hippocampal slices from 5xFAD APP/PS1 model mice, both for LTP and LTD. The reversal by the N-Aβcore correlated with alleviation of downregulation of hippocampal AMPA-type glutamate receptors in preparations from 5xFAD mice. The action of the N-Aβcore depended upon a critical di-histidine sequence and involved the phosphoinositide-3 (PI3) kinase pathway via mTOR (mammalian target of rapamycin). Together, the present findings indicate that the non-toxic N-Aβcore hexapeptide is not only neuroprotective at the cellular level but is able to reverse synaptic dysfunction in AD-like models, specifically alterations in synaptic plasticity.
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Affiliation(s)
| | | | | | | | - Robert A. Nichols
- Department of Cell & Molecular Biology, John A. Burns School of Medicine, University of Hawai‘i at Mānoa, Honolulu, HI, United States
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7
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Latif-Hernandez A, Sabanov V, Ahmed T, Craessaerts K, Saito T, Saido T, Balschun D. The two faces of synaptic failure in App NL-G-F knock-in mice. Alzheimers Res Ther 2020; 12:100. [PMID: 32838792 PMCID: PMC7445922 DOI: 10.1186/s13195-020-00667-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 08/10/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND Intensive basic and preclinical research into Alzheimer's disease (AD) has yielded important new findings, but they could not yet been translated into effective therapies. One of the reasons is the lack of animal models that sufficiently reproduce the complexity of human AD and the response of human brain circuits to novel treatment approaches. As a step in overcoming these limitations, new App knock-in models have been developed that avoid transgenic APP overexpression and its associated side effects. These mice are proposed to serve as valuable models to examine Aß-related pathology in "preclinical AD." METHODS Since AD as the most common form of dementia progresses into synaptic failure as a major cause of cognitive deficits, the detailed characterization of synaptic dysfunction in these new models is essential. Here, we addressed this by extracellular and whole-cell patch-clamp recordings in AppNL-G-F mice compared to AppNL animals which served as controls. RESULTS We found a beginning synaptic impairment (LTP deficit) at 3-4 months in the prefrontal cortex of AppNL-G-F mice that is further aggravated and extended to the hippocampus at 6-8 months. Measurements of miniature EPSCs and IPSCs point to a marked increase in excitatory and inhibitory presynaptic activity, the latter accompanied by a moderate increase in postsynaptic inhibitory function. CONCLUSIONS Our data reveal a marked impairment of primarily postsynaptic processes at the level of synaptic plasticity but the dominance of a presumably compensatory presynaptic upregulation at the level of elementary miniature synaptic function.
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Affiliation(s)
- Amira Latif-Hernandez
- Brain and Cognition, KU Leuven, Tiensestraat 102, Box 3714, 3000, Leuven, Belgium
- Present Address: Neurology and Neurological Sciences, Stanford Medicine, Stanford, USA
| | - Victor Sabanov
- Brain and Cognition, KU Leuven, Tiensestraat 102, Box 3714, 3000, Leuven, Belgium
- Leuven Brain Institute, KU Leuven, Leuven, Belgium
| | - Tariq Ahmed
- Brain and Cognition, KU Leuven, Tiensestraat 102, Box 3714, 3000, Leuven, Belgium
- Present Address: Qatar Biomedical Research Institute, Ar-Rayyan, Qatar
| | - Katleen Craessaerts
- Leuven Brain Institute, KU Leuven, Leuven, Belgium
- Laboratory for the Research of Neurodegenerative Diseases, VIB Center for the Biology of Disease, Leuven, Belgium
| | - Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, Japan
- Present Address: Department of Neurocognitive Science, Nagoya City University Graduate School of Medical Science, Nagoya, Aichi, Japan
| | - Takaomi Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, Japan
| | - Detlef Balschun
- Brain and Cognition, KU Leuven, Tiensestraat 102, Box 3714, 3000, Leuven, Belgium.
- Leuven Brain Institute, KU Leuven, Leuven, Belgium.
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8
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Moreno A. Molecular mechanisms of forgetting. Eur J Neurosci 2020; 54:6912-6932. [DOI: 10.1111/ejn.14839] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 04/23/2020] [Accepted: 05/18/2020] [Indexed: 11/30/2022]
Affiliation(s)
- Andrea Moreno
- Danish Institute of Translational Neuroscience (DANDRITE) Aarhus University Aarhus C Denmark
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9
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Vyas Y, Montgomery JM, Cheyne JE. Hippocampal Deficits in Amyloid-β-Related Rodent Models of Alzheimer's Disease. Front Neurosci 2020; 14:266. [PMID: 32317913 PMCID: PMC7154147 DOI: 10.3389/fnins.2020.00266] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 03/09/2020] [Indexed: 12/18/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease that is the most common cause of dementia. Symptoms of AD include memory loss, disorientation, mood and behavior changes, confusion, unfounded suspicions, and eventually, difficulty speaking, swallowing, and walking. These symptoms are caused by neuronal degeneration and cell loss that begins in the hippocampus, and later in disease progression spreading to the rest of the brain. While there are some medications that alleviate initial symptoms, there are currently no treatments that stop disease progression. Hippocampal deficits in amyloid-β-related rodent models of AD have revealed synaptic, behavioral and circuit-level defects. These changes in synaptic function, plasticity, neuronal excitability, brain connectivity, and excitation/inhibition imbalance all have profound effects on circuit function, which in turn could exacerbate disease progression. Despite, the wealth of studies on AD pathology we don't yet have a complete understanding of hippocampal deficits in AD. With the increasing development of in vivo recording techniques in awake and freely moving animals, future studies will extend our current knowledge of the mechanisms underpinning how hippocampal function is altered in AD, and aid in progression of treatment strategies that prevent and/or delay AD symptoms.
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Affiliation(s)
| | - Johanna M. Montgomery
- Department of Physiology, Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - Juliette E. Cheyne
- Department of Physiology, Centre for Brain Research, University of Auckland, Auckland, New Zealand
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10
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Flores-Muñoz C, Gómez B, Mery E, Mujica P, Gajardo I, Córdova C, Lopez-Espíndola D, Durán-Aniotz C, Hetz C, Muñoz P, Gonzalez-Jamett AM, Ardiles ÁO. Acute Pannexin 1 Blockade Mitigates Early Synaptic Plasticity Defects in a Mouse Model of Alzheimer's Disease. Front Cell Neurosci 2020; 14:46. [PMID: 32265655 PMCID: PMC7103637 DOI: 10.3389/fncel.2020.00046] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 02/18/2020] [Indexed: 12/11/2022] Open
Abstract
Synaptic loss induced by soluble oligomeric forms of the amyloid β peptide (sAβos) is one of the earliest events in Alzheimer’s disease (AD) and is thought to be the major cause of the cognitive deficits. These abnormalities rely on defects in synaptic plasticity, a series of events manifested as activity-dependent modifications in synaptic structure and function. It has been reported that pannexin 1 (Panx1), a nonselective channel implicated in cell communication and intracellular signaling, modulates the induction of excitatory synaptic plasticity under physiological contexts and contributes to neuronal death under inflammatory conditions. Here, we decided to study the involvement of Panx1 in functional and structural defects observed in excitatory synapses of the amyloid precursor protein (APP)/presenilin 1 (PS1) transgenic (Tg) mice, an animal model of AD. We found an age-dependent increase in the Panx1 expression that correlates with increased Aβ levels in hippocampal tissue from Tg mice. Congruently, we also observed an exacerbated Panx1 activity upon basal conditions and in response to glutamate receptor activation. The acute inhibition of Panx1 activity with the drug probenecid (PBN) did not change neurodegenerative parameters such as amyloid deposition or astrogliosis, but it significantly reduced excitatory synaptic defects in the AD model by normalizing long-term potentiation (LTP) and depression and improving dendritic arborization and spine density in hippocampal neurons of the Tg mice. These results suggest a major contribution of Panx1 in the early mechanisms leading to the synaptopathy in AD. Indeed, PBN induced a reduction in the activation of p38 mitogen-activated protein kinase (MAPK), a kinase widely implicated in the early neurotoxic signaling in AD. Our data strongly suggest that an enhanced expression and activation of Panx1 channels contribute to the Aβ-induced cascades leading to synaptic dysfunction in AD.
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Affiliation(s)
- Carolina Flores-Muñoz
- Centro de Neurología Traslacional, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile.,Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile.,Programa de Doctorado en Ciencias, Mención Neurociencia, Universidad de Valparaíso, Valparaíso, Chile
| | - Bárbara Gómez
- Centro de Neurología Traslacional, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile.,Escuela de Tecnología Médica, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile
| | - Elena Mery
- Centro de Neurología Traslacional, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile.,Escuela de Tecnología Médica, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile
| | - Paula Mujica
- Centro de Neurología Traslacional, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile.,Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile.,Programa de Doctorado en Ciencias, Mención Neurociencia, Universidad de Valparaíso, Valparaíso, Chile
| | - Ivana Gajardo
- Centro de Neurología Traslacional, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile
| | - Claudio Córdova
- Laboratorio de Estructura y Función Celular, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile
| | - Daniela Lopez-Espíndola
- Programa de Doctorado en Ciencias, Mención Neurociencia, Universidad de Valparaíso, Valparaíso, Chile.,Centro de Investigaciones Biomédicas, Escuela de Medicina, Universidad de Valparaíso, Valparaíso, Chile
| | - Claudia Durán-Aniotz
- Center for Social and Cognitive Neuroscience (CSCN), School of Psychology, Universidad Adolfo Ibáñez, Santiago de Chile, Chile.,Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile.,Center for Geroscience, Brain Health and Metabolism, Santiago, Chile
| | - Claudio Hetz
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile.,Center for Geroscience, Brain Health and Metabolism, Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
| | - Pablo Muñoz
- Centro de Neurología Traslacional, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile.,Centro de Investigaciones Biomédicas, Escuela de Medicina, Universidad de Valparaíso, Valparaíso, Chile
| | - Arlek M Gonzalez-Jamett
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile
| | - Álvaro O Ardiles
- Centro de Neurología Traslacional, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile.,Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile.,Centro Interdisciplinario de Estudios en Salud, Facultad de Medicina, Universidad de Valparaíso, Viña del Mar, Chile
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11
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Synaptic GluN2A-Containing NMDA Receptors: From Physiology to Pathological Synaptic Plasticity. Int J Mol Sci 2020; 21:ijms21041538. [PMID: 32102377 PMCID: PMC7073220 DOI: 10.3390/ijms21041538] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 12/16/2022] Open
Abstract
N-Methyl-d-Aspartate Receptors (NMDARs) are ionotropic glutamate-gated receptors. NMDARs are tetramers composed by several homologous subunits of GluN1-, GluN2-, or GluN3-type, leading to the existence in the central nervous system of a high variety of receptor subtypes with different pharmacological and signaling properties. NMDAR subunit composition is strictly regulated during development and by activity-dependent synaptic plasticity. Given the differences between GluN2 regulatory subunits of NMDAR in several functions, here we will focus on the synaptic pool of NMDARs containing the GluN2A subunit, addressing its role in both physiology and pathological synaptic plasticity as well as the contribution in these events of different types of GluN2A-interacting proteins.
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12
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Faldini E, Ahmed T, Bueé L, Blum D, Balschun D. Tau- but not Aß -pathology enhances NMDAR-dependent depotentiation in AD-mouse models. Acta Neuropathol Commun 2019; 7:202. [PMID: 31815648 PMCID: PMC6902514 DOI: 10.1186/s40478-019-0813-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 09/22/2019] [Indexed: 11/10/2022] Open
Abstract
Many mouse models of Alzheimer's disease (AD) exhibit impairments in hippocampal long-term-potentiation (LTP), seemingly corroborating the strong correlation between synaptic loss and cognitive decline reported in human studies. In other AD mouse models LTP is unaffected, but other defects in synaptic plasticity may still be present. We recently reported that THY-Tau22 transgenic mice, that overexpress human Tau protein carrying P301S and G272 V mutations and show normal LTP upon high-frequency-stimulation (HFS), develop severe changes in NMDAR mediated long-term-depression (LTD), the physiological counterpart of LTP. In the present study, we focused on putative effects of AD-related pathologies on depotentiation (DP), another form of synaptic plasticity. Using a novel protocol to induce DP in the CA1-region, we found in 11-15 months old male THY-Tau22 and APPPS1-21 transgenic mice that DP was not deteriorated by Aß pathology while significantly compromised by Tau pathology. Our findings advocate DP as a complementary form of synaptic plasticity that may help in elucidating synaptic pathomechanisms associated with different types of dementia.
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13
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Abstract
The Amyloid Precursor Protein (APP) is infamous for its proposed pivotal role in the pathogenesis of Alzheimer’s disease (AD). Much research on APP focusses on potential contributions to neurodegeneration, mostly based on mouse models with altered expression or mutated forms of APP. However, cumulative evidence from recent years indicates the indispensability of APP and its metabolites for normal brain physiology. APP contributes to the regulation of synaptic transmission, plasticity, and calcium homeostasis. It plays an important role during development and it exerts neuroprotective effects. Of particular importance is the soluble secreted fragment APPsα which mediates many of its physiological actions, often counteracting the effects of the small APP-derived peptide Aβ. Understanding the contribution of APP for normal functions of the nervous system is of high importance, both from a basic science perspective and also as a basis for generating new pathophysiological concepts and therapeutic approaches in AD. In this article, we review the physiological functions of APP and its metabolites, focusing on synaptic transmission, plasticity, calcium signaling, and neuronal network activity.
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Affiliation(s)
- Dimitri Hefter
- Institute of Physiology and Pathophysiology, Heidelberg University, Heidelberg, Germany.,RG Animal Models in Psychiatry, Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
| | - Susann Ludewig
- Helmholtz Centre for Infection Research, Neuroinflammation and Neurodegeneration Group, Braunschweig, Germany.,Cellular Neurobiology, Zoological Institute, Technical University Braunschweig, Braunschweig, Germany
| | - Andreas Draguhn
- Institute of Physiology and Pathophysiology, Heidelberg University, Heidelberg, Germany
| | - Martin Korte
- Helmholtz Centre for Infection Research, Neuroinflammation and Neurodegeneration Group, Braunschweig, Germany.,Cellular Neurobiology, Zoological Institute, Technical University Braunschweig, Braunschweig, Germany
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14
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Jang JH, Kim YK, Jung WM, Kim HK, Song EM, Kim HY, Oh JY, Park JY, Ryu Y, Song MY, Park HJ. Acupuncture Improves Comorbid Cognitive Impairments Induced by Neuropathic Pain in Mice. Front Neurosci 2019; 13:995. [PMID: 31616240 PMCID: PMC6763606 DOI: 10.3389/fnins.2019.00995] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 09/03/2019] [Indexed: 12/17/2022] Open
Abstract
Growing evidence indicates that neuropathic pain is frequently accompanied by cognitive impairments, which aggravate the quality of life of chronic pain patients. Here, we investigated whether acupuncture treatments can improve cognitive dysfunction as well as allodynia induced by neuropathic pain in mice. One week after the left partial sciatic nerve ligation (PSNL), acupuncture treatments on the acupoints GB30-GB34 (AP1), HT7-GV20 (AP2), or control points (CP) were performed for 4 weeks. Notably, the significant attenuations of mechanical allodynia and cognitive impairment were observed in the AP1 group, but not in PSNL, AP2, or CP groups. A random decision forest classifier based on the pain and cognitive functions displayed that the acupuncture group was clearly segregated from the other groups. We also demonstrated that acupuncture restored the reduced field excitatory post-synaptic potentials and was able to elevate the expression levels of glutamate receptors (NR2B and GluR1) in the hippocampus. Moreover, the expressions of Ca2+/calmodulin-dependent protein kinase II and synaptic proteins (pPSD-95 and pSyn-1) were enhanced by acupuncture treatment. These results suggest that acupuncture can enhance hippocampal long-term action through the regulation of the synaptic efficacy and that acupuncture may provide a viable option for managing both pain and cognitive functions associated with chronic neuropathic pain.
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Affiliation(s)
- Jae-Hwan Jang
- Acupuncture and Meridian Science Research Center, Kyung Hee University, Seoul, South Korea.,Department of Korean Medical Science, Graduate School of Korean Medicine, Kyung Hee University, Seoul, South Korea.,BK21 PLUS Korean Medicine Science Center, College of Korean Medicine, Kyung Hee University, Seoul, South Korea
| | - Yu-Kang Kim
- Acupuncture and Meridian Science Research Center, Kyung Hee University, Seoul, South Korea.,Department of Korean Medical Science, Graduate School of Korean Medicine, Kyung Hee University, Seoul, South Korea
| | | | - Hyung-Kyu Kim
- Department of Oral Physiology, School of Dentistry, Kyungpook National University, Daegu, South Korea
| | - Eun-Mo Song
- Department of Physical Medicine and Rehabilitation, Graduate School of Korean Medicine, Kyung Hee University, Seoul, South Korea
| | - Hee-Young Kim
- College of Korean Medicine, Daegu Haany University, Daegu, South Korea
| | - Ju-Young Oh
- Acupuncture and Meridian Science Research Center, Kyung Hee University, Seoul, South Korea.,Department of Korean Medical Science, Graduate School of Korean Medicine, Kyung Hee University, Seoul, South Korea.,BK21 PLUS Korean Medicine Science Center, College of Korean Medicine, Kyung Hee University, Seoul, South Korea
| | - Ji-Yeun Park
- College of Korean Medicine, Daejeon University, Daejeon, South Korea
| | - Yeonhee Ryu
- Korea Institute of Oriental Medicine, Daejeon, South Korea
| | - Mi-Yeon Song
- Department of Physical Medicine and Rehabilitation, Graduate School of Korean Medicine, Kyung Hee University, Seoul, South Korea
| | - Hi-Joon Park
- Acupuncture and Meridian Science Research Center, Kyung Hee University, Seoul, South Korea.,Department of Korean Medical Science, Graduate School of Korean Medicine, Kyung Hee University, Seoul, South Korea.,BK21 PLUS Korean Medicine Science Center, College of Korean Medicine, Kyung Hee University, Seoul, South Korea
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15
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Lyon MS, Milligan C. Extracellular heat shock proteins in neurodegenerative diseases: New perspectives. Neurosci Lett 2019; 711:134462. [PMID: 31476356 DOI: 10.1016/j.neulet.2019.134462] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 08/23/2019] [Accepted: 08/24/2019] [Indexed: 01/20/2023]
Abstract
One pathological hallmark of neurodegenerative diseases and CNS trauma is accumulation of insoluble, hydrophobic molecules and protein aggregations found both within and outside cells. These may be the consequences of an inadequate or overburdened cellular response to stresses resulting from potentially toxic changes in extra- and intracellular environments. The upregulated expression of heat shock proteins (HSPs) is one example of a highly conserved cellular response to both internal and external stress. Intracellularly these proteins act as chaperones, playing vital roles in the folding of nascent polypeptides, the translocation of proteins between subcellular locations, and the disaggregation of misfolded or aggregated proteins in an attempt to maintain cellular proteostasis during both homeostatic and stressful conditions. While the predominant study of the HSPs has focused on their intracellular chaperone functions, it remains unclear if all neuronal populations can mount a complete stress response. Alternately, it is now well established that some members of this family of proteins can be secreted by nearby, non-neuronal cells to act in the extracellular environment. This review addresses the current literature detailing the use of exogenous and extracellular HSPs in the treatment of cellular and animal models of neurodegenerative disease. These findings offer a new measure of therapeutic potential to the HSPs, but obstacles must be overcome before they can be efficiently used in a clinical setting.
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Affiliation(s)
- Miles S Lyon
- Department of Neurobiology and Anatomy, Wake Forest School of Medicine, Winston-Salem, NC 27157, United States
| | - Carol Milligan
- Department of Neurobiology and Anatomy, Wake Forest School of Medicine, Winston-Salem, NC 27157, United States.
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16
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Qi Y, Klyubin I, Hu NW, Ondrejcak T, Rowan MJ. Pre-plaque Aß-Mediated Impairment of Synaptic Depotentiation in a Transgenic Rat Model of Alzheimer's Disease Amyloidosis. Front Neurosci 2019; 13:861. [PMID: 31474823 PMCID: PMC6702302 DOI: 10.3389/fnins.2019.00861] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 07/31/2019] [Indexed: 11/13/2022] Open
Abstract
How endogenously produced soluble amyloid ß-protein (Aß) affects synaptic plasticity in vulnerable circuits should provide insight into early Alzheimer's disease pathophysiology. McGill-R-Thy1-APP transgenic rats, modeling Alzheimer's disease amyloidosis, exhibit an age-dependent soluble Aß-mediated impairment of the induction of long-term potentiation (LTP) by 200 Hz conditioning stimulation at apical CA3-to-CA1 synapses. Here, we investigated if synaptic weakening at these synapses in the form of activity-dependent persistent reversal (depotentiation) of LTP is also altered in pre-plaque rats in vivo. In freely behaving transgenic rats strong, 400 Hz, conditioning stimulation induced stable LTP that was NMDA receptor- and voltage-gated Ca2+ channel-dependent. Surprisingly, the ability of novelty exploration to induce depotentiation of 400 Hz-induced LTP was impaired in an Aß-dependent manner in the freely behaving transgenic rats. Moreover, at apical synapses, low frequency conditioning stimulation (1 Hz) did not trigger depotentiation in anaesthetized transgenic rats, with an age-dependence similar to the LTP deficit. In contrast, at basal synapses neither LTP, induced by 100 or 200 Hz, nor novelty exploration-induced depotentiation was impaired in the freely behaving transgenic rats. These findings indicate that activity-dependent weakening, as well as strengthening, is impaired in a synapse- and age-dependent manner in this model of early Alzheimer's disease amyloidosis.
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Affiliation(s)
- Yingjie Qi
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | - Igor Klyubin
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | - Neng-Wei Hu
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland.,Department of Physiology and Neurobiology, Zhengzhou University School of Medicine, Zhengzhou, China
| | - Tomas Ondrejcak
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | - Michael J Rowan
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
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17
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Marino C, Krishnan B, Cappello F, Taglialatela G. Hsp60 Protects against Amyloid β Oligomer Synaptic Toxicity via Modification of Toxic Oligomer Conformation. ACS Chem Neurosci 2019; 10:2858-2867. [PMID: 31091411 DOI: 10.1021/acschemneuro.9b00086] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Alzheimer's disease (AD) is the leading cause of dementia worldwide. While the etiology of AD remains uncertain, neurotoxic effects of amyloid beta oligomers (Aβo) on synaptic function, a well-established early event in AD, is an attractive area for the development of novel strategies to modify or cease the disease's progression. In this work, we tested the protective action of the mitochondrial chaperone Hsp60 against Aβo neurotoxicity, by determining the direct effect of Hsp60 in changing Aβo toxic conformations and thus reducing their dysfunctional synaptic binding and consequent suppression of long-term potentiation. Our data suggest that Hsp60 has a direct impact on Aβo, resulting in a reduction of cytotoxicity and rescue of Aβo-driven synaptic damage, thus proposing Hsp60 as an attractive therapeutic target candidate.
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Affiliation(s)
- Claudia Marino
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, Texas 77555-1045 United States
- Department of Biomedicine, Neuroscience and Advanced Diagnostics, University of Palermo, 90127 Palermo, Italy
| | - Balaji Krishnan
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, Texas 77555-1045 United States
| | - Francesco Cappello
- Department of Biomedicine, Neuroscience and Advanced Diagnostics, University of Palermo, 90127 Palermo, Italy
| | - Giulio Taglialatela
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, Texas 77555-1045 United States
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18
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Tamano H, Takiguchi M, Shimaya R, Adlard PA, Bush AI, Takeda A. Extracellular Zn 2+-independently attenuated LTP by human amyloid β 1-40 and rat amyloid β 1-42. Biochem Biophys Res Commun 2019; 514:888-892. [PMID: 31084925 DOI: 10.1016/j.bbrc.2019.05.037] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 05/04/2019] [Indexed: 12/31/2022]
Abstract
Human amyloid-β1-40 (Aβ1-40) and rat Aβ1-42 have lower affinity for extracellular Zn2+ than human Aβ1-42. Here we report extracellular Zn2+-independent attenuation of dentate gyrus long-term potentiation (LTP) by human Aβ1-40 and rat Aβ1-42. On the basis of the data that dentate gyrus LTP is extracellular Zn2+-dependently attenuated after local injection of human Aβ1-42 (25 pmol, 1 μl) into the dentate gyrus, which increases intracellular Zn2+ in the dentate gyrus, the toxicity of human Aβ1-40 and rat Aβ1-42 was compared in the in vivo system with human Aβ1-42. Dentate gyrus LTP was attenuated after injection of human Aβ1-40 and rat Aβ1-42 (25 pmol, 1 μl) into the dentate gyrus, which did not increase intracellular Zn2+ in the dentate gyrus. The attenuated LTP was not rescued by co-injection of CaEDTA, an extracellular Zn2+ chelator. The present study suggests that human Aβ1-40 and rat Aβ1-42 affect cognitive activity via extracellular Zn2+-independent mechanism at low micromolar concentration.
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Affiliation(s)
- Haruna Tamano
- Department of Neurophysiology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan
| | - Mako Takiguchi
- Department of Neurophysiology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan
| | - Ryota Shimaya
- Department of Neurophysiology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan
| | - Paul A Adlard
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - Ashley I Bush
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - Atsushi Takeda
- Department of Neurophysiology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan.
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19
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Marcello E, Musardo S, Vandermeulen L, Pelucchi S, Gardoni F, Santo N, Antonucci F, Di Luca M. Amyloid-β Oligomers Regulate ADAM10 Synaptic Localization Through Aberrant Plasticity Phenomena. Mol Neurobiol 2019; 56:7136-7143. [PMID: 30989630 PMCID: PMC6728288 DOI: 10.1007/s12035-019-1583-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 03/21/2019] [Indexed: 11/30/2022]
Abstract
A disintegrin and metalloproteinase 10 (ADAM10) is a synaptic enzyme that has been previously shown to limit amyloid-β1–42 (Aβ1–42) peptide formation in Alzheimer’s disease (AD). Furthermore, ADAM10 participates to spine shaping through the cleavage of adhesion molecules and its activity is under the control of synaptic plasticity events. In particular, long-term depression (LTD) promotes ADAM10 synaptic localization triggering its forward trafficking to the synapse, while long-term potentiation elicits ADAM10 internalization. Here, we show that a short-term in vitro exposure to Aβ1–42 oligomers, at a concentration capable of inducing synaptic depression and spine loss, triggers an increase in ADAM10 synaptic localization in hippocampal neuronal cultures. However, the Aβ1–42 oligomers-induced synaptic depression does not foster ADAM10 delivery to the synapse, as the physiological LTD, but impairs ADAM10 endocytosis. Moreover, Aβ1–42 oligomers-induced inhibition of ADAM10 internalization requires neuronal activity and the activation of the NMDA receptors. These data suggest that, at the synaptic level, Aβ1–42 oligomers trigger an aberrant plasticity mechanism according to which Aβ1–42 oligomers can downregulate Aβ generation through the modulation of ADAM10 synaptic availability. Moreover, the increased activity of ADAM10 towards its synaptic substrates could also affect the structural plasticity phenomena. Overall, these data shed new lights on the strict and complex relationship existing between synaptic activity and the primary mechanisms of AD pathogenesis.
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Affiliation(s)
- Elena Marcello
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy.
| | - Stefano Musardo
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy
- Department of Basic Neuroscience, University of Geneva, Rue Michel-Servet 1, 1206, Geneva, Switzerland
| | - Lina Vandermeulen
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy
| | - Silvia Pelucchi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Florence, Italy
| | - Fabrizio Gardoni
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy
| | - Nadia Santo
- Department of Life Sciences, Università degli Studi di Milano, Milan, Italy
| | - Flavia Antonucci
- Department of Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Monica Di Luca
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy.
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20
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Ondrejcak T, Hu NW, Qi Y, Klyubin I, Corbett GT, Fraser G, Perkinton MS, Walsh DM, Billinton A, Rowan MJ. Soluble tau aggregates inhibit synaptic long-term depression and amyloid β-facilitated LTD in vivo. Neurobiol Dis 2019; 127:582-590. [PMID: 30910746 DOI: 10.1016/j.nbd.2019.03.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 03/01/2019] [Accepted: 03/21/2019] [Indexed: 01/29/2023] Open
Abstract
Soluble synaptotoxic aggregates of the main pathological proteins of Alzheimer's disease, amyloid β-protein (Aß) and tau, have rapid and potent inhibitory effects on long-term potentiation (LTP). Although the promotion of synaptic weakening mechanisms, including long-term depression (LTD), is posited to mediate LTP inhibition by Aß, little is known regarding the action of exogenous tau on LTD. The present study examined the ability of different assemblies of full-length human tau to affect LTD in the dorsal hippocampus of the anaesthetized rat. Unlike Aß, intracerebroventricular injection of soluble aggregates of tau (SτAs), but not monomers or fibrils, potently increased the threshold for LTD induction in a manner that required cellular prion protein. However, MTEP, an antagonist of the putative prion protein coreceptor metabotropic glutamate receptor 5, did not prevent the disruption of synaptic plasticity by SτAs. In contrast, systemic treatment with Ro 25-6981, a selective antagonist at GluN2B subunit-containing NMDA receptors, reduced SτA-mediated inhibition of LTD, but not LTP. Intriguingly, SτAs completely blocked Aß-facilitated LTD, whereas a subthreshold dose of SτAs facilitated Aß-mediated inhibition of LTP. Overall, these findings support the importance of cellular prion protein in mediating a range of, sometimes opposing, actions of soluble Aß and tau aggregates with different effector mechanisms on synaptic plasticity.
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Affiliation(s)
- Tomas Ondrejcak
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland.
| | - Neng-Wei Hu
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland; Department of Physiology and Neurobiology, Zhengzhou University School of Medicine, Zhengzhou 450001, China
| | - Yingjie Qi
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Igor Klyubin
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Grant T Corbett
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham & Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Graham Fraser
- Neuroscience, IMED Biotech Unit, AstraZeneca, Cambridge CB21 6GH, UK
| | | | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham & Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Andrew Billinton
- Neuroscience, IMED Biotech Unit, AstraZeneca, Cambridge CB21 6GH, UK
| | - Michael J Rowan
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland.
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21
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Liu J, Chang L, Song Y, Li H, Wu Y. The Role of NMDA Receptors in Alzheimer's Disease. Front Neurosci 2019; 13:43. [PMID: 30800052 PMCID: PMC6375899 DOI: 10.3389/fnins.2019.00043] [Citation(s) in RCA: 224] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 01/16/2019] [Indexed: 12/13/2022] Open
Abstract
In Alzheimer’s disease (AD), early synaptic dysfunction is associated with the increased oligomeric amyloid-beta peptide, which causes NMDAR-dependent synaptic depression and spine elimination. Memantine, low-affinity NMDAR channel blocker, has been used in the treatment of moderate to severe AD. However, clear evidence is still deficient in demonstrating the underlying mechanisms and a relationship between NMDARs dysfunction and AD. This review focuses on not only changes in expression of different NMDAR subunits, but also some unconventional modes of NMDAR action.
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Affiliation(s)
- Jinping Liu
- School of Medicine, Tsinghua University, Beijing, China
| | - Lirong Chang
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Yizhi Song
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Hui Li
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Yan Wu
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
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22
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Zádori D, Veres G, Szalárdy L, Klivényi P, Vécsei L. Alzheimer's Disease: Recent Concepts on the Relation of Mitochondrial Disturbances, Excitotoxicity, Neuroinflammation, and Kynurenines. J Alzheimers Dis 2019; 62:523-547. [PMID: 29480191 DOI: 10.3233/jad-170929] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The pathomechanism of Alzheimer's disease (AD) certainly involves mitochondrial disturbances, glutamate excitotoxicity, and neuroinflammation. The three main aspects of mitochondrial dysfunction in AD, i.e., the defects in dynamics, altered bioenergetics, and the deficient transport, act synergistically. In addition, glutamatergic neurotransmission is affected in several ways. The balance between synaptic and extrasynaptic glutamatergic transmission is shifted toward the extrasynaptic site contributing to glutamate excitotoxicity, a phenomenon augmented by increased glutamate release and decreased glutamate uptake. Neuroinflammation in AD is predominantly linked to central players of the innate immune system, with central nervous system (CNS)-resident microglia, astroglia, and perivascular macrophages having been implicated at the cellular level. Several abnormalities have been described regarding the activation of certain steps of the kynurenine (KYN) pathway of tryptophan metabolism in AD. First of all, the activation of indolamine 2,3-dioxygenase, the first and rate-limiting step of the pathway, is well-demonstrated. 3-Hydroxy-L-KYN and its metabolite, 3-hydroxy-anthranilic acid have pro-oxidant, antioxidant, and potent immunomodulatory features, giving relevance to their alterations in AD. Another metabolite, quinolinic acid, has been demonstrated to be neurotoxic, promoting glutamate excitotoxicity, reactive oxygen species production, lipid peroxidation, and microglial neuroinflammation, and its abundant presence in AD pathologies has been demonstrated. Finally, the neuroprotective metabolite, kynurenic acid, has been associated with antagonistic effects at glutamate receptors, free radical scavenging, and immunomodulation, giving rise to potential therapeutic implications. This review presents the multiple connections of KYN pathway-related alterations to three main domains of AD pathomechanism, such as mitochondrial dysfunction, excitotoxicity, and neuroinflammation, implicating possible therapeutic options.
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Affiliation(s)
- Dénes Zádori
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary
| | - Gábor Veres
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary
| | - Levente Szalárdy
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary
| | - Péter Klivényi
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary
| | - László Vécsei
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary.,MTA-SZTE Neuroscience Research Group, Szeged, Hungary
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23
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Qian Q, Zhang J, He FP, Bao WX, Zheng TT, Zhou DM, Pan HY, Zhang H, Zhang XQ, He X, Sun BG, Luo BY, Chen C, Peng GP. Down-regulated expression of microRNA-338-5p contributes to neuropathology in Alzheimer's disease. FASEB J 2018; 33:4404-4417. [PMID: 30576233 DOI: 10.1096/fj.201801846r] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Alzheimer's disease (AD) is a leading cause of dementia. However, the mechanisms responsible for development of AD, especially for the sporadic variant, are still not clear. In our previous study, we discovered that a small noncoding RNA (miR-188-3p) targeting β-site amyloid precursor protein cleaving enzyme (BACE)-1, a key enzyme responsible for Aβ formation, plays an important role in the development of neuropathology in AD. In the present study, we identified that miR-338-5p, a new miRNA that also targets BACE1, contributes to AD neuropathology. We observed that expression of miR-338-5p was significantly down-regulated in the hippocampus of patients with AD and 5XFAD transgenic (TG) mice, an animal model of AD. Overexpression of miR-338-5p in the hippocampus of TG mice reduced BACE1 expression, Aβ formation, and neuroinflammation. Overexpression of miR-338-5p functionally prevented impairments in long-term synaptic plasticity, learning ability, and memory retention in TG mice. In addition, we provide evidence that down-regulated expression of miR-338-5p in AD is regulated through the NF-κB signaling pathway. Our results suggest that down-regulated expression of miR-338-5p plays an important role in the development of AD.-Qian, Q., Zhang, J., He, F.-P., Bao, W.-X., Zheng, T.-T., Zhou, D.-M., Pan, H.-Y., Zhang, H., Zhang, X.-Q., He, X., Sun, B.-G., Luo, B.-Y., Chen, C., Peng, G.-P. Down-regulated expression of microRNA-338-5p contributes to neuropathology in Alzheimer's disease.
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Affiliation(s)
- Qi Qian
- Department of Neurology, Center for Brain Sciences, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Neuroscience Center of Excellence, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA.,College of Basic Medical Sciences, Zhejiang Chinese Medical University, Hangzhou, China; and
| | - Jian Zhang
- Neuroscience Center of Excellence, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA
| | - Fang-Ping He
- Department of Neurology, Center for Brain Sciences, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Wang-Xiao Bao
- Department of Neurology, Center for Brain Sciences, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Ting-Ting Zheng
- The First Affiliated Hospital, Zhejiang Chinese Medical University, Hangzhou, China.,Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Dong-Ming Zhou
- Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Hong-Yu Pan
- Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Heng Zhang
- Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiao-Qin Zhang
- Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiao He
- Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Bing-Gui Sun
- Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Ben-Yan Luo
- Department of Neurology, Center for Brain Sciences, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Chu Chen
- Neuroscience Center of Excellence, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA
| | - Guo-Ping Peng
- Department of Neurology, Center for Brain Sciences, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
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24
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Diosmin is neuroprotective in a rat model of scopolamine-induced cognitive impairment. Biomed Pharmacother 2018; 108:1376-1383. [DOI: 10.1016/j.biopha.2018.09.127] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 09/21/2018] [Accepted: 09/24/2018] [Indexed: 01/02/2023] Open
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25
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Karthick C, Nithiyanandan S, Essa MM, Guillemin GJ, Jayachandran SK, Anusuyadevi M. Time-dependent effect of oligomeric amyloid-β (1-42)-induced hippocampal neurodegeneration in rat model of Alzheimer's disease. Neurol Res 2018; 41:139-150. [PMID: 30453864 DOI: 10.1080/01616412.2018.1544745] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Alzheimer's disease (AD) is characterized with an abnormal deposition of insoluble amyloid-beta (Aβ) peptide plaques, tangles formation and synaptic dysfunction. These result in impaired functioning of neuronal circuits and alter the behavioral response owing to activation of neurotransmitter receptors. Recently, it has been implicated that Aβ influences N-methyl d-aspartate (NMDA) receptor activation in AD; however, the molecular mechanism underlying remains unclear. Thus, emerged specific aim to study the time-course effect of oligomeric Aβ(1-42) (oAβ1-42) on the mRNA expression of genes encoding NMDA and acetylcholine receptors in the rat model of AD. METHODS Aggregated forms of synthetic Aβ peptides were injected bilaterally into the intrahippocampal region of rat brain using stereotaxic surgery. Behavioral analysis was performed using eight-arm Radial Arm Maze task at the end of experimental period. Euthanized rat brain hippocampal tissue was used to study the mRNA expression of glutamatergic and cholinergic receptor using semiquantitative reverse transcription-polymerase chain reaction. RESULTS oAβ1-42 decreased the gene expression level of α7-nicotinic acetylcholine receptor and increased the mRNA expression of NMDA receptor 2A, and -2B subunits. In particular, oAβ1-42 aggregates increased the retention time and altered the behavioral response in rats after 15 days of injection. Further, amyloid-β1-42 are highly expressed in 15 days after postinjection in hippocampus of adult rats. CONCLUSION Acute exposure of oAβ1-42 modulated differential gene expression of glutamatergic and cholinergic receptors in hippocampus of adult rats and is duration dependent reflecting changes in hippocampal circuitry system underlying learning and memory impairments. ABBREVIATIONS AD: Alzheimer's disease, Aβ: amyloid-β; oAβ1-42: oligomeric amyloid-β 1-42 full length peptide; CAM: calmodulin; CNS: central nervous system; CR: Congo red; DG: dentate gyrus; EC: entorhinal cortex; HFIP: 1,1,1,3,3,3-hexafluoro-2-propanol; IBO: ibotenic acid; NMDA: N-methyl d-aspartate; NMDAR: N-methyl d-aspartate receptor; NR2A: N-methyl d-aspartate receptor 2A; NR2B: N-methyl d-aspartate receptor 2B; ACh: acetylcholine; α7-nAChR: α7-nicotinic acetylcholine receptor; PBS: phosphate buffered saline; RAM: Radial Arm Maze; ThT: thioflavin T.
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Affiliation(s)
- Chennakesavan Karthick
- a Molecular Gerontology Laboratory, Department of Biochemistry , School of Life Sciences, Bharathidasan University , Tiruchirappalli , India
| | - Saravanan Nithiyanandan
- a Molecular Gerontology Laboratory, Department of Biochemistry , School of Life Sciences, Bharathidasan University , Tiruchirappalli , India
| | - Musthafa Mohamed Essa
- b Department of Food Science and Nutrition , College of Agriculture and Marine Sciences, Sultan Qaboos University , Muscat , Oman
| | - Gilles J Guillemin
- c Neuroinflammation group, Faculty of Medicine and Health Sciences, Deb Bailey MND Research Laboratory , Macquaire University , Sydney , Australia
| | - Swaminathan K Jayachandran
- d Molecular Cardiology and Drug Discovery Laboratory, Department of Bioinformatics , School of Life Sciences, Bharathidasan University , Tiruchirappalli , India
| | - Muthuswamy Anusuyadevi
- a Molecular Gerontology Laboratory, Department of Biochemistry , School of Life Sciences, Bharathidasan University , Tiruchirappalli , India
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26
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Susceptibility to Aβo and TBOA of LTD and Extrasynaptic NMDAR-Dependent Tonic Current in the Aged Rat Hippocampus. Neurochem Res 2018; 44:692-702. [PMID: 30426348 DOI: 10.1007/s11064-018-2677-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 10/26/2018] [Accepted: 11/02/2018] [Indexed: 12/29/2022]
Abstract
Aging, as the major risk factor of Alzheimer's disease (AD), may increase susceptibility to neurodegenerative diseases through many gradual molecular and biochemical changes. Extracellular glutamate homeostasis and extrasynaptic glutamate N-methyl-D-aspartate receptors (NMDAR) are among early synaptic targets of oligomeric amyloid β (Aβo), one of the AD related synaptotoxic protein species. In this study, we asked for the effects of Aβo on long-term depression (LTD), a form of synaptic plasticity dependent on extrasynaptic NMDAR activation, and on a tonic current (TC) resulting from the activation of extrasynaptic NMDAR by ambient glutamate in hippocampal slices from young (3-6-month-old) and aged (24-28-month-old) Sprague-Dawley rats. Aβo significantly enhanced the magnitude of LTD and the amplitude of TC in aged slices compared to young ones. TBOA, a glutamate transporter inhibitor, also significantly increased LTD magnitude and TC amplitude in slices from aged rats, suggesting either an age-related weakness of the glutamate clearance system and/or a facilitated extrasynaptic NMDAR activation. From our present data, we hypothesize that senescence-related impairment of the extrasynaptic environment may be a vector of vulnerability of the aged hippocampus to neurodegenerative promotors such as Aβo.
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27
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Postsynaptic p47phox regulates long-term depression in the hippocampus. Cell Discov 2018; 4:44. [PMID: 30181899 PMCID: PMC6110736 DOI: 10.1038/s41421-018-0046-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 05/30/2018] [Accepted: 05/31/2018] [Indexed: 12/17/2022] Open
Abstract
It is well documented that reactive oxygen species (ROS) affects neurodegeneration in the brain. Several studies also implicate ROS in the regulation of synapse function and learning and memory processes, although the precise source of ROS generation within these contexts remains to be further explored. Here we show that postsynaptic superoxide generation through PKCζ-activated NADPH oxidase 2 (NOX2) is critical for long-term depression (LTD) of synaptic transmission in the CA1-Shaffer collateral synapse of the rat hippocampus. Specifically, PKCζ-dependent phosphorylation of p47phox at serine 316, a NOX2 regulatory subunit, is required for LTD but is not necessary for long-term potentiation (LTP). Our data suggest that postsynaptic p47phox phosphorylation at serine 316 is a key upstream determinant for LTD and synapse weakening.
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28
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Mango D, Nisticò R. Role of ASIC1a in Aβ-induced synaptic alterations in the hippocampus. Pharmacol Res 2018; 131:61-65. [PMID: 29574226 DOI: 10.1016/j.phrs.2018.03.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 03/19/2018] [Accepted: 03/20/2018] [Indexed: 10/17/2022]
Abstract
Acid-sensing ion channels (ASICs) are widely expressed in the mammalian central nervous system where they play a key role in synaptic transmission and in specific forms of memory. On the other hand, ASICs can be persistently active under pathological conditions contributing to neuronal damage in ischemic stroke, brain trauma, epilepsy and Parkinson's disease. However, to date no experimental evidence has linked ASICs to Alzheimer's disease (AD). Aim of the present work was to investigate, in CA1 pyramidal neurons, the possible involvement of ASIC1a in the Aβ-mediated effect on metabotropic glutamate (mGlu) receptor dependent transmission. We found that, in slices pretreated with Aβ, the pharmacological blockade of ASIC1a restored the increased intrinsic excitability following group I mGlu receptor activation. This suggests that, under certain conditions, ASIC1a might further contribute to the Aβ-related depolarizing response. We have recently demonstrated that ASIC1a is also involved long-term depression (LTD) induced either by low-frequency stimulation or by application of the group I mGlu receptor agonist DHPG. Here, we have shown that psalmotoxin-1, a selective blocker of ASIC1a, rescued the DHPG-LTD facilitation associated with genetic and non-genetic models of AD. Overall, these results suggest that a functional coupling between ASIC1a and mGlu receptors occurs and might contribute to the synaptic alterations associated with AD.
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Affiliation(s)
- D Mango
- Laboratory of Neuropharmacology, European Brain Research Institute, Rita Levi-Montalcini Foundation, Rome, Italy.
| | - R Nisticò
- Laboratory of Neuropharmacology, European Brain Research Institute, Rita Levi-Montalcini Foundation, Rome, Italy; Department of Biology, University of Rome Tor Vergata, Rome, Italy.
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29
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Rajmohan R, Reddy PH. Amyloid-Beta and Phosphorylated Tau Accumulations Cause Abnormalities at Synapses of Alzheimer's disease Neurons. J Alzheimers Dis 2018; 57:975-999. [PMID: 27567878 DOI: 10.3233/jad-160612] [Citation(s) in RCA: 267] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Amyloid-beta (Aβ) and hyperphosphorylated tau are hallmark lesions of Alzheimer's disease (AD). However, the loss of synapses and dysfunctions of neurotransmission are more directly tied to disease severity. The role of these lesions in the pathoetiological progression of the disease remains contested. Biochemical, cellular, molecular, and pathological studies provided several lines of evidence and improved our understanding of how Aβ and hyperphosphorylated tau accumulation may directly harm synapses and alter neurotransmission. In vitro evidence suggests that Aβ and hyperphosphorylated tau have both direct and indirect cytotoxic effects that affect neurotransmission, axonal transport, signaling cascades, organelle function, and immune response in ways that lead to synaptic loss and dysfunctions in neurotransmitter release. Observations in preclinical models and autopsy studies support these findings, suggesting that while the pathoetiology of positive lesions remains elusive, their removal may reduce disease severity and progression. The purpose of this article is to highlight the need for further investigation of the role of tau in disease progression and its interactions with Aβ and neurotransmitters alike.
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Affiliation(s)
- Ravi Rajmohan
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - P Hemachandra Reddy
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA.,Department of Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX, USA.,Department of Cell Biology & Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, USA.,Department of Neurology, Texas Tech University Health Sciences Center, Lubbock, TX, USA.,Department of Speech, Language and Hearing Sciences, Texas Tech University Health Sciences Center, Lubbock, TX, USA
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30
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Peineau S, Rabiant K, Pierrefiche O, Potier B. Synaptic plasticity modulation by circulating peptides and metaplasticity: Involvement in Alzheimer's disease. Pharmacol Res 2018; 130:385-401. [PMID: 29425728 DOI: 10.1016/j.phrs.2018.01.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 01/23/2018] [Accepted: 01/26/2018] [Indexed: 10/18/2022]
Abstract
Synaptic plasticity is a cellular process involved in learning and memory whose alteration in its two main forms (Long Term Depression (LTD) and Long Term Potentiation (LTP)), is observed in most brain pathologies, including neurodegenerative disorders such as Alzheimer's disease (AD). In humans, AD is associated at the cellular level with neuropathological lesions composed of extracellular deposits of β-amyloid (Aβ) protein aggregates and intracellular neurofibrillary tangles, cellular loss, neuroinflammation and a general brain homeostasis dysregulation. Thus, a dramatic synaptic environment perturbation is observed in AD patients, involving changes in brain neuropeptides, cytokines, growth factors or chemokines concentration and diffusion. Studies performed in animal models demonstrate that these circulating peptides strongly affect synaptic functions and in particular synaptic plasticity. Besides this neuromodulatory action of circulating peptides, other synaptic plasticity regulation mechanisms such as metaplasticity are altered in AD animal models. Here, we will review new insights into the study of synaptic plasticity regulatory/modulatory mechanisms which could influence the process of synaptic plasticity in the context of AD with a particular attention to the role of metaplasticity and peptide dependent neuromodulation.
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Affiliation(s)
- Stéphane Peineau
- GRAP UMR1247, INSERM, Centre Universitaire de Recherche en Santé, Université de Picardie Jules Verne, Amiens, France; Centre for Synaptic Plasticity, School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, UK.
| | - Kevin Rabiant
- GRAP UMR1247, INSERM, Centre Universitaire de Recherche en Santé, Université de Picardie Jules Verne, Amiens, France
| | - Olivier Pierrefiche
- GRAP UMR1247, INSERM, Centre Universitaire de Recherche en Santé, Université de Picardie Jules Verne, Amiens, France.
| | - Brigitte Potier
- Laboratoire Aimé Cotton, CNRS-ENS UMR9188, Université Paris-Sud, Orsay, France.
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31
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Musardo S, Marcello E. Synaptic dysfunction in Alzheimer's disease: From the role of amyloid β-peptide to the α-secretase ADAM10. Eur J Pharmacol 2017. [DOI: 10.1016/j.ejphar.2017.06.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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32
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Endophilin2 Interacts with GluA1 to Mediate AMPA Receptor Endocytosis Induced by Oligomeric Amyloid- β. Neural Plast 2017; 2017:8197085. [PMID: 28758034 PMCID: PMC5516760 DOI: 10.1155/2017/8197085] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 05/08/2017] [Accepted: 06/08/2017] [Indexed: 01/08/2023] Open
Abstract
Amyloid-β (Aβ) plays an important role in Alzheimer's disease (AD), as oligomeric Aβ induces loss of postsynaptic AMPA receptors (AMPARs) leading to cognitive deficits. The loss of postsynaptic AMPARs is mediated through the clathrin-dependent endocytosis pathway, in which endophilin2 is one of the important regulatory proteins. Endophilin2, which is enriched in both the pre- and postsynaptic membrane, has previously been reported to be important for recycling of synaptic vesicles at the presynaptic membrane. However, the role of endophilin2 in oligomeric Aβ-induced postsynaptic AMPAR endocytosis is not well understood. In this study, we show that endophilin2 does not affect constitutive AMPAR endocytosis. Endophilin2 knockdown, but not overexpression, resisted oligomeric Aβ-induced AMPAR dysfunction. Moreover, endophilin2 colocalized and interacted with GluA1, a subunit of AMPAR, to regulate oligomeric Aβ-induced AMPAR endocytosis. Thus, we have determined a role of endophilin2 in oligomeric Aβ-induced postsynaptic AMPAR dysfunction, indicating possible directions for preventing the loss of AMPARs in cognitive impairment and providing evidence for the clinical treatment of AD.
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33
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Pinar C, Fontaine CJ, Triviño-Paredes J, Lottenberg CP, Gil-Mohapel J, Christie BR. Revisiting the flip side: Long-term depression of synaptic efficacy in the hippocampus. Neurosci Biobehav Rev 2017. [PMID: 28624435 DOI: 10.1016/j.neubiorev.2017.06.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Synaptic plasticity is widely regarded as a putative biological substrate for learning and memory processes. While both decreases and increases in synaptic strength are seen as playing a role in learning and memory, long-term depression (LTD) of synaptic efficacy has received far less attention than its counterpart long-term potentiation (LTP). Never-the-less, LTD at synapses can play an important role in increasing computational flexibility in neural networks. In addition, like learning and memory processes, the magnitude of LTD can be modulated by factors that include stress and sex hormones, neurotrophic support, learning environments, and age. Examining how these factors modulate hippocampal LTD can provide the means to better elucidate the molecular underpinnings of learning and memory processes. This is in turn will enhance our appreciation of how both increases and decreases in synaptic plasticity can play a role in different neurodevelopmental and neurodegenerative conditions.
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Affiliation(s)
- Cristina Pinar
- Division of Medical Sciences and UBC Island Medical Program, University of Victoria, Victoria, British Columbia, Canada
| | - Christine J Fontaine
- Division of Medical Sciences and UBC Island Medical Program, University of Victoria, Victoria, British Columbia, Canada
| | - Juan Triviño-Paredes
- Division of Medical Sciences and UBC Island Medical Program, University of Victoria, Victoria, British Columbia, Canada
| | - Carina P Lottenberg
- Division of Medical Sciences and UBC Island Medical Program, University of Victoria, Victoria, British Columbia, Canada; Faculty of Medical Sciences of Santa Casa de São Paulo, Sao Paulo, SP, Brazil
| | - Joana Gil-Mohapel
- Division of Medical Sciences and UBC Island Medical Program, University of Victoria, Victoria, British Columbia, Canada
| | - Brian R Christie
- Division of Medical Sciences and UBC Island Medical Program, University of Victoria, Victoria, British Columbia, Canada.
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Arbel-Ornath M, Hudry E, Boivin JR, Hashimoto T, Takeda S, Kuchibhotla KV, Hou S, Lattarulo CR, Belcher AM, Shakerdge N, Trujillo PB, Muzikansky A, Betensky RA, Hyman BT, Bacskai BJ. Soluble oligomeric amyloid-β induces calcium dyshomeostasis that precedes synapse loss in the living mouse brain. Mol Neurodegener 2017; 12:27. [PMID: 28327181 PMCID: PMC5361864 DOI: 10.1186/s13024-017-0169-9] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 03/17/2017] [Indexed: 02/06/2023] Open
Abstract
Background Amyloid-β oligomers (oAβ) are thought to mediate neurotoxicity in Alzheimer’s disease (AD), and previous studies in AD transgenic mice suggest that calcium dysregulation may contribute to these pathological effects. Even though AD mouse models remain a valuable resource to investigate amyloid neurotoxicity, the concomitant presence of soluble Aβ species, fibrillar Aβ, and fragments of amyloid precursor protein (APP) complicate the interpretation of the phenotypes. Method To explore the specific contribution of soluble oligomeric Aβ (oAβ) to calcium dyshomeostasis and synaptic morphological changes, we acutely exposed the healthy mouse brain, at 3 to 6 months of age, to naturally occurring soluble oligomers and investigated their effect on calcium levels using in vivo multiphoton imaging. Results We observed a dramatic increase in the levels of neuronal resting calcium, which was dependent upon extracellular calcium influx and activation of NMDA receptors. Ryanodine receptors, previously implicated in AD models, did not appear to be primarily involved using this experimental setting. We used the high resolution cortical volumes acquired in-vivo to measure the effect on synaptic densities and observed that, while spine density remained stable within the first hour of oAβ exposure, a significant decrease in the number of dendritic spines was observed 24 h post treatment, despite restoration of intraneuronal calcium levels at this time point. Conclusions These observations demonstrate a specific effect of oAβ on NMDA-mediated calcium influx, which triggers synaptic collapse in vivo. Moreover, this work leverages a method to quantitatively measure calcium concentration at the level of neuronal processes, cell bodies and single synaptic elements repeatedly and thus can be applicable to testing putative drugs and/or other intervention methodologies. Electronic supplementary material The online version of this article (doi:10.1186/s13024-017-0169-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Michal Arbel-Ornath
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA
| | - Eloise Hudry
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA
| | - Josiah R Boivin
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA
| | - Tadafumi Hashimoto
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA.,Department of Neuropathology, The University of Tokyo, Tokyo, Japan
| | - Shuko Takeda
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA
| | - Kishore V Kuchibhotla
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA.,Skirball Institute, NYU School of Medicine, New York, NY, 10016, USA
| | - Steven Hou
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA
| | - Carli R Lattarulo
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA
| | - Arianna M Belcher
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA
| | - Naomi Shakerdge
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA
| | - Pariss B Trujillo
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA
| | - Alona Muzikansky
- Department of Biostatistics, Harvard School of Public Health, 50 Staniford Street, Boston, MA, USA
| | - Rebecca A Betensky
- Department of Biostatistics, Harvard School of Public Health, 50 Staniford Street, Boston, MA, USA
| | - Bradley T Hyman
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA
| | - Brian J Bacskai
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA, 02129, USA.
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35
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Metabotropic glutamate receptors and neurodegenerative diseases. Pharmacol Res 2017; 115:179-191. [DOI: 10.1016/j.phrs.2016.11.013] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 11/11/2016] [Accepted: 11/15/2016] [Indexed: 12/21/2022]
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36
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Gilbert J, Shu S, Yang X, Lu Y, Zhu LQ, Man HY. β-Amyloid triggers aberrant over-scaling of homeostatic synaptic plasticity. Acta Neuropathol Commun 2016; 4:131. [PMID: 27955702 PMCID: PMC5154098 DOI: 10.1186/s40478-016-0398-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 11/29/2016] [Indexed: 11/21/2022] Open
Abstract
The over-production of β-amyloid (Aβ) has been strongly correlated to neuronal dysfunction and altered synaptic plasticity in Alzheimer’s disease (AD). Accordingly, it has been proposed that disrupted synaptic transmission and neuronal network instability underlie memory failure that is evident in the early phases of AD. Homeostatic synaptic plasticity (HSP) serves to restrain neuronal activity within a physiological range. Therefore a disruption of this mechanism may lead to destabilization in synaptic and neural circuit function. Here, we report that during HSP by neuronal activity deprivation, application of Aβ results in an aberrant over-response of the up-regulation of AMPA receptor (AMPAR)-mediated synaptic currents and cell-surface AMPAR expression. In the visual cortex, in vivo HSP induced by visual deprivation shows a similar over-response following an Aβ local injection. Aβ increases the expression of GluA2-lacking, calcium permeable AMPARs (CP-AMPARs), which are required for the initiation, but not maintenance of HSP. Both GluA2-lacking and GluA2-containing AMPARs contribute to the Aβ-mediated over-scaling of HSP. We also find that Aβ induces the dissociation of HDAC1 from the miR124 transcription factor EVI1, leading to an up-regulation of miR124 expression and increased amount of CP-AMPARs. Thus, via aberrant stimulation of miR124 expression and biogenesis of CP-AMPARs, Aβ is able to induce an over response in HSP. This Aβ-mediated dysregulation in homeostatic plasticity may play an important role in the pathogenesis of altered neural function and memory deficits in the early stages of AD.
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37
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Palop JJ, Mucke L. Network abnormalities and interneuron dysfunction in Alzheimer disease. Nat Rev Neurosci 2016; 17:777-792. [PMID: 27829687 DOI: 10.1038/nrn.2016.141] [Citation(s) in RCA: 594] [Impact Index Per Article: 74.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The function of neural circuits and networks can be controlled, in part, by modulating the synchrony of their components' activities. Network hypersynchrony and altered oscillatory rhythmic activity may contribute to cognitive abnormalities in Alzheimer disease (AD). In this condition, network activities that support cognition are altered decades before clinical disease onset, and these alterations predict future pathology and brain atrophy. Although the precise causes and pathophysiological consequences of these network alterations remain to be defined, interneuron dysfunction and network abnormalities have emerged as potential mechanisms of cognitive dysfunction in AD and related disorders. Here, we explore the concept that modulating these mechanisms may help to improve brain function in these conditions.
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Affiliation(s)
- Jorge J Palop
- Gladstone Institute of Neurological Disease, 1650 Owens Street, San Francisco, California 94158, USA.,Department of Neurology, University of California, San Francisco, 1650 Owens Street, San Francisco, California 94158, USA
| | - Lennart Mucke
- Gladstone Institute of Neurological Disease, 1650 Owens Street, San Francisco, California 94158, USA.,Department of Neurology, University of California, San Francisco, 1650 Owens Street, San Francisco, California 94158, USA
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38
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Infliximab ameliorates AD-associated object recognition memory impairment. Behav Brain Res 2016; 311:384-391. [DOI: 10.1016/j.bbr.2016.06.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 05/30/2016] [Accepted: 06/01/2016] [Indexed: 12/31/2022]
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39
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Regan P, Whitcomb DJ, Cho K. Physiological and Pathophysiological Implications of Synaptic Tau. Neuroscientist 2016; 23:137-151. [DOI: 10.1177/1073858416633439] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Tauopathies encompass a broad range of neurodegenerative diseases featuring extensive neuronal death and cognitive decline. However, research over the past 30 years has failed to significantly advance our understanding of how tau causes dementia, limiting the design of rational therapeutics. It has become evident that we need to expand our understanding of tau in physiology, in order to delineate how tau may contribute to pathology. This review discusses recent evidence that has uncovered a novel aspect of tau function, based on its previously uncharacterized localization to the synapse. Here, multiple streams of evidence support a critical role for synaptic tau in the regulation of synapse physiology. In particular, long-term depression, a form of synaptic weakening, is dependent on the presence of tau in hippocampal neurons. The regulation of tau by specific phosphorylation events downstream of GSK-3β activation appears to be integral to this signaling role. We also describe how the regulation of synapse physiology by tau and its phosphorylation may inform our understanding of tauopathies and comorbid diseases. This work should provide a platform for future tau biology research in addition to therapeutic design.
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Affiliation(s)
- Philip Regan
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology (HW-LINE), Bristol, UK
| | - Daniel J. Whitcomb
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology (HW-LINE), Bristol, UK
- Centre for Synaptic Plasticity, Faculty of Health Sciences, University of Bristol, Bristol, UK
| | - Kwangwook Cho
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology (HW-LINE), Bristol, UK
- Centre for Synaptic Plasticity, Faculty of Health Sciences, University of Bristol, Bristol, UK
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40
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Guntupalli S, Widagdo J, Anggono V. Amyloid-β-Induced Dysregulation of AMPA Receptor Trafficking. Neural Plast 2016; 2016:3204519. [PMID: 27073700 PMCID: PMC4814684 DOI: 10.1155/2016/3204519] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 02/28/2016] [Indexed: 01/22/2023] Open
Abstract
Evidence from neuropathological, genetic, animal model, and biochemical studies has indicated that the accumulation of amyloid-beta (Aβ) is associated with, and probably induces, profound neuronal changes in brain regions critical for memory and cognition in the development of Alzheimer's disease (AD). There is considerable evidence that synapses are particularly vulnerable to AD, establishing synaptic dysfunction as one of the earliest events in pathogenesis, prior to neuronal loss. It is clear that excessive Aβ levels can disrupt excitatory synaptic transmission and plasticity, mainly due to dysregulation of the AMPA and NMDA glutamate receptors in the brain. Importantly, AMPA receptors are the principal glutamate receptors that mediate fast excitatory neurotransmission. This is essential for synaptic plasticity, a cellular correlate of learning and memory, which are the cognitive functions that are most disrupted in AD. Here we review recent advances in the field and provide insights into the molecular mechanisms that underlie Aβ-induced dysfunction of AMPA receptor trafficking. This review focuses primarily on NMDA receptor- and metabotropic glutamate receptor-mediated signaling. In particular, we highlight several mechanisms that underlie synaptic long-term depression as common signaling pathways that are hijacked by the neurotoxic effects of Aβ.
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Affiliation(s)
- Sumasri Guntupalli
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Jocelyn Widagdo
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Victor Anggono
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
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41
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Unsain N, Barker PA. New Views on the Misconstrued: Executioner Caspases and Their Diverse Non-apoptotic Roles. Neuron 2016; 88:461-74. [PMID: 26539888 DOI: 10.1016/j.neuron.2015.08.029] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Initially characterized for their roles in apoptosis, executioner caspases have emerged as important regulators of an array of cellular activities. This is especially true in the nervous system, where sublethal caspase activity has been implicated in axonal pathfinding and branching, axonal degeneration, dendrite pruning, regeneration, long-term depression, and metaplasticity. Here we examine the roles of sublethal executioner caspase activity in nervous system development and maintenance, consider the mechanisms that locally activate and restrain these potential killers, and discuss how their activity be subverted in neurodegenerative disease.
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Affiliation(s)
- Nicolas Unsain
- Laboratorio de Neurobiología, Instituto de Investigación Médica Mercedes y Martín Ferreyra, Instituto Nacional de Investigación Médica Córdoba-Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Córdoba, Friuli 2434, Córdoba (5016), Argentina
| | - Philip A Barker
- Irving K. Barber School of Arts and Sciences, University of British Columbia, Kelowna, BC V1V 1V7, Canada.
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42
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Repression of the eIF2α kinase PERK alleviates mGluR-LTD impairments in a mouse model of Alzheimer's disease. Neurobiol Aging 2016; 41:19-24. [PMID: 27103515 DOI: 10.1016/j.neurobiolaging.2016.02.005] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 01/13/2016] [Accepted: 02/05/2016] [Indexed: 12/30/2022]
Abstract
Mounting evidence indicates that impairments of synaptic efficacy and/or plasticity may be a key step in the development of Alzheimer's disease (AD) pathophysiology. Among the 2 major forms of synaptic plasticity, long-term potentiation and long-term depression (LTD), much less is known about how LTD is regulated in AD and its molecular mechanisms. Recent studies indicate that metabotropic glutamate receptor 5 (mGluR5) may function as a receptor and/or co-receptor for amyloid beta. Herein, we examined mGluR-LTD in hippocampal slices from aged APP/PS1 mutant mice that model AD. Our findings demonstrate that mGluR-LTD is blocked in APP/PS1 mice, and that the mGluR-LTD failure is reversed by either genetically or pharmacologically suppressing the activity of PERK, a kinase for the mRNA translation factor eIF2α. These data are congruent with recent evidence that inhibition of eIF2α phosphorylation via PERK suppression and reversal of de novo protein synthesis deficits can mitigate cognitive deficits in neurodegenerative diseases. Together with reports indicating that mGluR5 may mediate amyloid beta synaptotoxicity, our findings offer insights into novel therapeutic targets for AD and other cognitive syndromes.
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43
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Lee K, Goodman L, Fourie C, Schenk S, Leitch B, Montgomery JM. AMPA Receptors as Therapeutic Targets for Neurological Disorders. ION CHANNELS AS THERAPEUTIC TARGETS, PART A 2016; 103:203-61. [DOI: 10.1016/bs.apcsb.2015.10.004] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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44
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Kaleka KS, Gerges NZ. Neurogranin restores amyloid β-mediated synaptic transmission and long-term potentiation deficits. Exp Neurol 2015; 277:115-123. [PMID: 26721336 DOI: 10.1016/j.expneurol.2015.12.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 12/08/2015] [Accepted: 12/18/2015] [Indexed: 11/16/2022]
Abstract
Amyloid β (Aβ) is widely considered one of the early causes of cognitive deficits observed in Alzheimer's disease. Many of the deficits caused by Aβ are attributed to its disruption of synaptic function represented by its blockade of long-term potentiation (LTP) and its induction of synaptic depression. Identifying pathways that reverse these synaptic deficits may open the door to new therapeutic targets. In this study, we explored the possibility that Neurogranin (Ng)-a postsynaptic calmodulin (CaM) targeting protein that enhances synaptic function-may rescue Aβ-mediated deficits in synaptic function. Our results show that Ng is able to reverse synaptic depression and LTP deficits induced by Aβ. Furthermore, Ng's restoration of synaptic transmission is through the insertion of GluA1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid glutamate receptors (AMPARs). These restorative effects of Ng are dependent on the interaction of Ng and CaM and CaM-dependent activation of CaMKII. Overall, this study identifies a novel mechanism to rescue synaptic deficits induced by Aβ oligomers. It also suggests Ng and CaM signaling as potential therapeutic targets for Alzheimer's disease as well as important tools to further explore the pathophysiology underlying the disease.
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Affiliation(s)
- Kanwardeep Singh Kaleka
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 West Watertown Plank Rd., Milwaukee, WI 53132, United States; Neuroscience Research Center, Medical College of Wisconsin, 8701 West Watertown Plank Rd., Milwaukee, WI 53132, United States
| | - Nashaat Z Gerges
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 West Watertown Plank Rd., Milwaukee, WI 53132, United States; Neuroscience Research Center, Medical College of Wisconsin, 8701 West Watertown Plank Rd., Milwaukee, WI 53132, United States.
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45
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Penazzi L, Bakota L, Brandt R. Microtubule Dynamics in Neuronal Development, Plasticity, and Neurodegeneration. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 321:89-169. [PMID: 26811287 DOI: 10.1016/bs.ircmb.2015.09.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Neurons are the basic information-processing units of the nervous system. In fulfilling their task, they establish a structural polarity with an axon that can be over a meter long and dendrites with a complex arbor, which can harbor ten-thousands of spines. Microtubules and their associated proteins play important roles during the development of neuronal morphology, the plasticity of neurons, and neurodegenerative processes. They are dynamic structures, which can quickly adapt to changes in the environment and establish a structural scaffold with high local variations in composition and stability. This review presents a comprehensive overview about the role of microtubules and their dynamic behavior during the formation and maturation of processes and spines in the healthy brain, during aging and under neurodegenerative conditions. The review ends with a discussion of microtubule-targeted therapies as a perspective for the supportive treatment of neurodegenerative disorders.
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Affiliation(s)
- Lorène Penazzi
- Department of Neurobiology, University of Osnabrück, Osnabrück, Germany
| | - Lidia Bakota
- Department of Neurobiology, University of Osnabrück, Osnabrück, Germany
| | - Roland Brandt
- Department of Neurobiology, University of Osnabrück, Osnabrück, Germany
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46
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Wang ZX, Tan L, Liu J, Yu JT. The Essential Role of Soluble Aβ Oligomers in Alzheimer's Disease. Mol Neurobiol 2015; 53:1905-1924. [PMID: 25833098 DOI: 10.1007/s12035-015-9143-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 03/18/2015] [Indexed: 01/21/2023]
Abstract
Alzheimer's disease (AD) is a common neurodegenerative disease characterized by amyloid plaque and neurofibrillary tangles (NFT). With the finding that soluble nonfibrillar Aβ levels actually correlate strongly with the severity of the disease, the initial focus on amyloid plaques shifted to the contemporary concept that AD memory failure is caused by soluble Aβ oligomers. The soluble Aβ are known to be more neurotoxicthan fibrillar Aβ species. In this paper, we summarize the essential role of soluble Aβ oligomers in AD and discuss therapeutic strategies that target soluble Aβ oligomers.
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Affiliation(s)
- Zi-Xuan Wang
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, China
| | - Lan Tan
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, China.
| | - Jinyuan Liu
- Columbia College, Columbia University, New York, NY, USA
| | - Jin-Tai Yu
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, China. .,Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA, USA.
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47
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Novkovic T, Shchyglo O, Gold R, Manahan-Vaughan D. Hippocampal function is compromised in an animal model of multiple sclerosis. Neuroscience 2015; 309:100-12. [PMID: 25795599 DOI: 10.1016/j.neuroscience.2015.03.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 02/11/2015] [Accepted: 03/04/2015] [Indexed: 11/30/2022]
Abstract
Multiple sclerosis (MS) is a progressive inflammatory autoimmune disease that is characterized by demyelination and axonal damage in the nervous system. One obvious consequence is a cumulative loss of muscle control. However, cognitive dysfunction affects roughly half of MS sufferers, sometimes already early in the disease course. Although long-term (remote) memory is typically unaffected, the ability to form new declarative memories becomes compromised. A major structure for the encoding of new declarative memories is the hippocampus. Encoding is believed to be mediated by synaptic plasticity in the form of long-term potentiation (LTP) and long-term depression (LTD) of synaptic strength. Here, in an animal model of MS we explored whether disease symptoms are accompanied by a loss of functional neuronal integrity, synaptic plasticity, or hippocampus-dependent learning ability. In mice that developed MOG35-55-induced experimental autoimmune encephalomyelitis (EAE), passive properties of CA1 pyramidal neurons were unaffected, although the ability to fire action potentials became reduced in the late phase of EAE. LTP remained normal in the early phase of MOG35-55-induced EAE. However, in the late phase, LTP was impaired and LTP-related spatial memory was impaired. In contrast, LTD and hippocampus-dependent object recognition memory were unaffected. These data suggest that in an animal model of MS hippocampal function becomes compromised as the disease progresses.
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Affiliation(s)
- T Novkovic
- Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Germany; International Graduate School of Neuroscience, Ruhr University Bochum, Germany
| | - O Shchyglo
- Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Germany; International Graduate School of Neuroscience, Ruhr University Bochum, Germany
| | - R Gold
- International Graduate School of Neuroscience, Ruhr University Bochum, Germany; Neurological University Clinic, St. Josef Hospital, Medical Faculty, Ruhr University Bochum, Germany
| | - D Manahan-Vaughan
- Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Germany; International Graduate School of Neuroscience, Ruhr University Bochum, Germany.
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48
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Ahmed T, Blum D, Burnouf S, Demeyer D, Buée-Scherrer V, D'Hooge R, Buée L, Balschun D. Rescue of impaired late-phase long-term depression in a tau transgenic mouse model. Neurobiol Aging 2014; 36:730-9. [PMID: 25443285 DOI: 10.1016/j.neurobiolaging.2014.09.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 09/01/2014] [Accepted: 09/17/2014] [Indexed: 12/18/2022]
Abstract
Cognitive decline, the hallmark of Alzheimer's disease, and accompanying neuropsychiatric symptoms share dysfunctions of synaptic processes as a common cellular pathomechanism. Long-term potentiation has proven to be a sensitive tool for the "diagnosis" of such synaptic dysfunctions. Much less, however, is known about how long-term depression (LTD), an alternative mechanism for the storage of memory, is affected by Alzheimer's disease progression. Here, we demonstrate that impaired late LTD (>3 hours) in THY-Tau22 mice can be rescued by either inhibition of glycogen synthase kinase-3 (GSK3β) activity or by application of the protein-phosphatase 2A agonist selenate. In line with these findings, we observed increased phosphorylation of GSK3β at Y216 and reduced total phosphatase activity in biochemical assays of hippocampal tissue of THY-Tau22 mice. Interestingly, LTD induction and pharmacologic inhibition of GSK3β appeared to downregulate GSK3ß activity via a marked upregulation of phosphorylation at the inhibitory Ser9 residue. Our results point to alterations in phosphorylation and/or dephosphorylation homeostasis as key mechanisms underlying the deficits in LTD and hippocampus-dependent learning found in THY-Tau22 mice.
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Affiliation(s)
- Tariq Ahmed
- Laboratory of Biological Psychology, University of Leuven, Leuven, Belgium
| | - David Blum
- Université Lille-Nord de France, UDSL, Lille, France; Inserm UMR837, Jean-Pierre Aubert Research Centre, Lille, France; CHRU-Lille, Lille, France
| | - Sylvie Burnouf
- Université Lille-Nord de France, UDSL, Lille, France; Inserm UMR837, Jean-Pierre Aubert Research Centre, Lille, France; Max-Planck Institute for Biology of Ageing, Köln, Germany
| | - Dominique Demeyer
- Université Lille-Nord de France, UDSL, Lille, France; Inserm UMR837, Jean-Pierre Aubert Research Centre, Lille, France
| | - Valérie Buée-Scherrer
- Université Lille-Nord de France, UDSL, Lille, France; Inserm UMR837, Jean-Pierre Aubert Research Centre, Lille, France; CHRU-Lille, Lille, France
| | - Rudi D'Hooge
- Laboratory of Biological Psychology, University of Leuven, Leuven, Belgium
| | - Luc Buée
- Université Lille-Nord de France, UDSL, Lille, France; Inserm UMR837, Jean-Pierre Aubert Research Centre, Lille, France; CHRU-Lille, Lille, France
| | - Detlef Balschun
- Laboratory of Biological Psychology, University of Leuven, Leuven, Belgium.
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49
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Karasawa T, Lombroso PJ. Disruption of striatal-enriched protein tyrosine phosphatase (STEP) function in neuropsychiatric disorders. Neurosci Res 2014; 89:1-9. [PMID: 25218562 DOI: 10.1016/j.neures.2014.08.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 08/12/2014] [Accepted: 08/21/2014] [Indexed: 10/24/2022]
Abstract
Striatal-enriched protein tyrosine phosphatase (STEP) is a brain-specific tyrosine phosphatase that plays a major role in the development of synaptic plasticity. Recent findings have implicated STEP in several psychiatric and neurological disorders, including Alzheimer's disease, schizophrenia, fragile X syndrome, Huntington's disease, stroke/ischemia, and stress-related psychiatric disorders. In these disorders, STEP protein expression levels and activity are dysregulated, contributing to the cognitive deficits that are present. In this review, we focus on the most recent findings on STEP, discuss how STEP expression and activity are maintained during normal cognitive function, and how disruptions in STEP activity contribute to a number of illnesses.
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Affiliation(s)
- Takatoshi Karasawa
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kasugai, Aichi 480-0392, Japan.
| | - Paul J Lombroso
- Departments of Neurobiology, Psychiatry and Child Study Center, Yale University School of Medicine, New Haven, CT 06520, USA
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50
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Kuwabara Y, Ishizeki M, Watamura N, Toba J, Yoshii A, Inoue T, Ohshima T. Impairments of long-term depression induction and motor coordination precede Aβ accumulation in the cerebellum of APPswe/PS1dE9 double transgenic mice. J Neurochem 2014; 130:432-43. [DOI: 10.1111/jnc.12728] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 03/23/2014] [Accepted: 03/27/2014] [Indexed: 12/22/2022]
Affiliation(s)
- Yuki Kuwabara
- Laboratory for Molecular Brain Science; Department of Life Science and Medical Bioscience; Waseda University; Tokyo Japan
| | - Masato Ishizeki
- Laboratory of Neurophysiology; Department of Life Science and Medical Bioscience; Waseda University; Tokyo Japan
| | - Naoto Watamura
- Laboratory for Molecular Brain Science; Department of Life Science and Medical Bioscience; Waseda University; Tokyo Japan
| | - Junya Toba
- Laboratory for Molecular Brain Science; Department of Life Science and Medical Bioscience; Waseda University; Tokyo Japan
| | - Aya Yoshii
- Laboratory for Molecular Brain Science; Department of Life Science and Medical Bioscience; Waseda University; Tokyo Japan
| | - Takafumi Inoue
- Laboratory of Neurophysiology; Department of Life Science and Medical Bioscience; Waseda University; Tokyo Japan
| | - Toshio Ohshima
- Laboratory for Molecular Brain Science; Department of Life Science and Medical Bioscience; Waseda University; Tokyo Japan
- Laboratory for Developmental Neurobiology; RIKEN Brain Science Institute; Wako Saitama Japan
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