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Pantelopulos GA, Abraham CB, Straub JE. Cholesterol and Lipid Rafts in the Biogenesis of Amyloid-β Protein and Alzheimer's Disease. Annu Rev Biophys 2024; 53:455-486. [PMID: 38382114 DOI: 10.1146/annurev-biophys-062823-023436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Cholesterol has been conjectured to be a modulator of the amyloid cascade, the mechanism that produces the amyloid-β (Aβ) peptides implicated in the onset of Alzheimer's disease. We propose that cholesterol impacts the genesis of Aβ not through direct interaction with proteins in the bilayer, but indirectly by inducing the liquid-ordered phase and accompanying liquid-liquid phase separations, which partition proteins in the amyloid cascade to different lipid domains and ultimately to different endocytotic pathways. We explore the full process of Aβ genesis in the context of liquid-ordered phases induced by cholesterol, including protein partitioning into lipid domains, mechanisms of endocytosis experienced by lipid domains and secretases, and pH-controlled activation of amyloid precursor protein secretases in specific endocytotic environments. Outstanding questions on the essential role of cholesterol in the amyloid cascade are identified for future studies.
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Affiliation(s)
| | - Conor B Abraham
- Department of Chemistry, Boston University, Boston, Massachusetts, USA;
| | - John E Straub
- Department of Chemistry, Boston University, Boston, Massachusetts, USA;
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2
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Chen BH, Lin ZY, Zeng XX, Jiang YH, Geng F. LRP4-related signalling pathways and their regulatory role in neurological diseases. Brain Res 2024; 1825:148705. [PMID: 38065285 DOI: 10.1016/j.brainres.2023.148705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 11/17/2023] [Accepted: 12/03/2023] [Indexed: 01/28/2024]
Abstract
The mechanism of action of low-density lipoprotein receptor related protein 4 (LRP4) is mediated largely via the Agrin-LRP4-MuSK signalling pathway in the nervous system. LRP4 contributes to the development of synapses in the peripheral nervous system (PNS). It interacts with signalling molecules such as the amyloid beta-protein precursor (APP) and the wingless type protein (Wnt). Its mechanisms of action are complex and mediated via interaction between the pre-synaptic motor neuron and post-synaptic muscle cell in the PNS, which enhances the development of the neuromuscular junction (NMJ). LRP4 may function differently in the central nervous system (CNS) than in the PNS, where it regulates ATP and glutamate release via astrocytes. It mayaffect the growth and development of the CNS by controlling the energy metabolism. LRP4 interacts with Agrin to maintain dendrite growth and density in the CNS. The goal of this article is to review the current studies involving relevant LRP4 signaling pathways in the nervous system. The review also discusses the clinical and etiological roles of LRP4 in neurological illnesses, such as myasthenia gravis, Alzheimer's disease and epilepsy. In this review, we provide a theoretical foundation for the pathogenesis and therapeutic application of LRP4 in neurologic diseases.
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Affiliation(s)
- Bai-Hui Chen
- Department of Physiology, Shantou University Medical College, Shantou 515041, China
| | - Ze-Yu Lin
- Department of Physiology, Shantou University Medical College, Shantou 515041, China
| | - Xiao-Xue Zeng
- Department of Physiology, Shantou University Medical College, Shantou 515041, China
| | - Yi-Han Jiang
- Department of Physiology, Shantou University Medical College, Shantou 515041, China
| | - Fei Geng
- Department of Physiology, Shantou University Medical College, Shantou 515041, China; Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, China.
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3
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Haut F, Argyrousi EK, Arancio O. Re-Arranging the Puzzle between the Amyloid-Beta and Tau Pathology: An APP-Centric Approach. Int J Mol Sci 2023; 25:259. [PMID: 38203429 PMCID: PMC10779219 DOI: 10.3390/ijms25010259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 12/04/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024] Open
Abstract
After several years of research in the field of Alzheimer's disease (AD), it is still unclear how amyloid-beta (Aβ) and Tau, two key hallmarks of the disease, mediate the neuropathogenic events that lead to AD. Current data challenge the "Amyloid Cascade Hypothesis" that has prevailed in the field of AD, stating that Aβ precedes and triggers Tau pathology that will eventually become the toxic entity in the progression of the disease. This perspective also led the field of therapeutic approaches towards the development of strategies that target Aβ or Tau. In the present review, we discuss recent literature regarding the neurotoxic role of both Aβ and Tau in AD, as well as their physiological function in the healthy brain. Consequently, we present studies suggesting that Aβ and Tau act independently of each other in mediating neurotoxicity in AD, thereafter, re-evaluating the "Amyloid Cascade Hypothesis" that places Tau pathology downstream of Aβ. More recent studies have confirmed that both Aβ and Tau could propagate the disease and induce synaptic and memory impairments via the amyloid precursor protein (APP). This finding is not only interesting from a mechanistic point of view since it provides better insights into the AD pathogenesis but also from a therapeutic point of view since it renders APP a common downstream effector for both Aβ and Tau. Subsequently, therapeutic strategies that act on APP might provide a more viable and physiologically relevant approach for targeting AD.
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Affiliation(s)
- Florence Haut
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S, New York, NY 10032, USA; (F.H.); (E.K.A.)
| | - Elentina K. Argyrousi
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S, New York, NY 10032, USA; (F.H.); (E.K.A.)
| | - Ottavio Arancio
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S, New York, NY 10032, USA; (F.H.); (E.K.A.)
- Department of Medicine, Columbia University, New York, NY 10032, USA
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA
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4
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Abstract
Neurodegenerative diseases are characterized by the progressive loss of structure or function of neurons. In this Spotlight, we explore the idea that genetic forms of neurodegenerative disorders might be rooted in neural development. Focusing on Alzheimer's, Parkinson's and Huntington's disease, we first provide a brief overview of the pathology for these diseases. Although neurodegenerative diseases are generally thought of as late-onset diseases, we discuss recent evidence promoting the notion that they might be considered neurodevelopmental disorders. With this view in mind, we consider the suitability of animal models for studying these diseases, highlighting human-specific features of human brain development. We conclude by proposing that one such feature, human-specific regulation of neurogenic time, might be key to understanding the etiology and pathophysiology of human neurodegenerative disease.
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Affiliation(s)
- Khadijeh Shabani
- Institut du Cerveau – Paris Brain Institute – ICM, Sorbonne Université, Inserm, CNRS, Hôpital Pitié-Salpêtrière, 75013 Paris, France
| | - Bassem A. Hassan
- Institut du Cerveau – Paris Brain Institute – ICM, Sorbonne Université, Inserm, CNRS, Hôpital Pitié-Salpêtrière, 75013 Paris, France
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5
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Pfundstein G, Nikonenko AG, Sytnyk V. Amyloid precursor protein (APP) and amyloid β (Aβ) interact with cell adhesion molecules: Implications in Alzheimer’s disease and normal physiology. Front Cell Dev Biol 2022; 10:969547. [PMID: 35959488 PMCID: PMC9360506 DOI: 10.3389/fcell.2022.969547] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 07/07/2022] [Indexed: 11/16/2022] Open
Abstract
Alzheimer’s disease (AD) is an incurable neurodegenerative disorder in which dysfunction and loss of synapses and neurons lead to cognitive impairment and death. Accumulation and aggregation of neurotoxic amyloid-β (Aβ) peptides generated via amyloidogenic processing of amyloid precursor protein (APP) is considered to play a central role in the disease etiology. APP interacts with cell adhesion molecules, which influence the normal physiological functions of APP, its amyloidogenic and non-amyloidogenic processing, and formation of Aβ aggregates. These cell surface glycoproteins also mediate attachment of Aβ to the neuronal cell surface and induce intracellular signaling contributing to Aβ toxicity. In this review, we discuss the current knowledge surrounding the interactions of cell adhesion molecules with APP and Aβ and analyze the evidence of the critical role these proteins play in regulating the processing and physiological function of APP as well as Aβ toxicity. This is a necessary piece of the complex AD puzzle, which we should understand in order to develop safe and effective therapeutic interventions for AD.
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Affiliation(s)
- Grant Pfundstein
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | | | - Vladimir Sytnyk
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
- *Correspondence: Vladimir Sytnyk,
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6
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Antonino M, Marmo P, Freites CL, Quassollo GE, Sánchez MF, Lorenzo A, Bignante EA. Aβ Assemblies Promote Amyloidogenic Processing of APP and Intracellular Accumulation of Aβ42 Through Go/Gβγ Signaling. Front Cell Dev Biol 2022; 10:852738. [PMID: 35445022 PMCID: PMC9013780 DOI: 10.3389/fcell.2022.852738] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 03/07/2022] [Indexed: 12/16/2022] Open
Abstract
Alzheimer’s disease (AD) is characterized by the deposition of aggregated species of amyloid beta (Aβ) in the brain, which leads to progressive cognitive deficits and dementia. Aβ is generated by the successive cleavage of the amyloid precursor protein (APP), first by β-site APP cleaving enzyme 1 (BACE1) and subsequently by the γ-secretase complex. Those conditions which enhace or reduce its clearance predispose to Aβ aggregation and the development of AD. In vitro studies have demonstrated that Aβ assemblies spark a feed-forward loop heightening Aβ production. However, the underlying mechanism remains unknown. Here, we show that oligomers and fibrils of Aβ enhance colocalization and physical interaction of APP and BACE1 in recycling endosomes of human neurons derived from induced pluripotent stem cells and other cell types, which leads to exacerbated amyloidogenic processing of APP and intracellular accumulation of Aβ42. In cells that are overexpressing the mutant forms of APP which are unable to bind Aβ or to activate Go protein, we have found that treatment with aggregated Aβ fails to increase colocalization of APP with BACE1 indicating that Aβ-APP/Go signaling is involved in this process. Moreover, inhibition of Gβγ subunit signaling with βARKct or gallein prevents Aβ-dependent interaction of APP and BACE1 in endosomes, β-processing of APP, and intracellular accumulation of Aβ42. Collectively, our findings uncover a signaling mechanism leading to a feed-forward loop of amyloidogenesis that might contribute to Aβ pathology in the early stages of AD and suggest that gallein could have therapeutic potential.
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Affiliation(s)
- Magdalena Antonino
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Paula Marmo
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Carlos Leandro Freites
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | | | | | - Alfredo Lorenzo
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
- *Correspondence: Elena Anahi Bignante, ; Alfredo Lorenzo,
| | - Elena Anahi Bignante
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
- Instituto Universitario de Ciencias Biomédicas de Córdoba (IUCBC), Córdoba, Argentina
- *Correspondence: Elena Anahi Bignante, ; Alfredo Lorenzo,
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7
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Genetic deletion of α7 nicotinic acetylcholine receptors induces an age-dependent Alzheimer's disease-like pathology. Prog Neurobiol 2021; 206:102154. [PMID: 34453977 DOI: 10.1016/j.pneurobio.2021.102154] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 05/29/2021] [Accepted: 08/18/2021] [Indexed: 11/22/2022]
Abstract
The accumulation of amyloid-beta peptide (Aβ) and the failure of cholinergic transmission are key players in Alzheimer's disease (AD). However, in the healthy brain, Aβ contributes to synaptic plasticity and memory acting through α7 subtype nicotinic acetylcholine receptors (α7nAChRs). Here, we hypothesized that the α7nAChR deletion blocks Aβ physiological function and promotes a compensatory increase in Aβ levels that, in turn, triggers an AD-like pathology. To validate this hypothesis, we studied the age-dependent phenotype of α7 knock out mice. We found that α7nAChR deletion caused an impairment of hippocampal synaptic plasticity and memory at 12 months of age, paralleled by an increase of Amyloid Precursor Protein expression and Aβ levels. This was accompanied by other classical AD features such as a hyperphosphorylation of tau at residues Ser 199, Ser 396, Thr 205, a decrease of GSK-3β at Ser 9, the presence of paired helical filaments and neurofibrillary tangles, neuronal loss and an increase of GFAP-positive astrocytes. Our findings suggest that α7nAChR malfunction might precede Aβ and tau pathology, offering a different perspective to interpret the failure of anti-Aβ therapies against AD and to find novel therapeutical approaches aimed at restoring α7nAChRs-mediated Aβ function at the synapse.
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8
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Yamamoto K, Yamamoto R, Kato N. Amyloid β and Amyloid Precursor Protein Synergistically Suppress Large-Conductance Calcium-Activated Potassium Channel in Cortical Neurons. Front Aging Neurosci 2021; 13:660319. [PMID: 34149396 PMCID: PMC8211014 DOI: 10.3389/fnagi.2021.660319] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 04/20/2021] [Indexed: 12/03/2022] Open
Abstract
Intracellular amyloid β (Aβ) injection suppresses the large-conductance calcium-dependent potassium (BK) channel in cortical pyramidal cells from wild-type (WT) mice. In 3xTg Alzheimer’s disease (AD) model mice, intraneuronal Aβ is genetically programed to accumulate, which suppresses the BK channel. However, the mode of BK channel suppression remained unclarified. The present report revealed that only one (11A1) of the three anti-Aβ-oligomer antibodies that we examined, but not anti-monomer-Aβ-antibodies, was effective in recovering BK channel activity in 3xTg neurons. Antibodies against amyloid precursor protein (APP) were also found to be effective, suggesting that APP plays an essential part in this Aβ-oligomer-induced BK channel suppression in 3xTg neurons. In WT neurons, by contrast, APP suppressed BK channels by itself, which suggests that either APP or Aβ is sufficient to block BK channels, thus pointing to a different co-operativity of Aβ and APP in WT and 3xTg neurons. To clarify this difference, we relied on our previous finding that the scaffold protein Homer1a reverses the BK channel blockade in both WT and 3xTg neurons. In cortical neurons from 3xTg mice that bear Homer1a knockout (4xTg mice), neither anti-APP antibodies nor 11A1, but only the 6E10 antibody that binds both APP and Aβ, rescued the BK channel suppression. Given that Homer1a expression is activity dependent and 3xTg neurons are hyperexcitable, Homer1a is likely to be expressed sufficiently in 3xTg neurons, thereby alleviating the suppressive influence of APP and Aβ on BK channel. A unique way that APP modifies Aβ toxicity is thus proposed.
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Affiliation(s)
- Kenji Yamamoto
- Department of Physiology, Kanazawa Medical University, Ishikawa, Japan.,Department of Neurology and Clinical Research Center, National Hospital Organization Utano National Hospital, Kyoto, Japan
| | - Ryo Yamamoto
- Department of Physiology, Kanazawa Medical University, Ishikawa, Japan
| | - Nobuo Kato
- Department of Physiology, Kanazawa Medical University, Ishikawa, Japan
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9
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Yoo JY, Kim HB, Baik TK, Lee JH, Woo RS. Neuregulin 1/ErbB4/Akt signaling attenuates cytotoxicity mediated by the APP-CT31 fragment of amyloid precursor protein. Exp Mol Pathol 2021; 120:104622. [PMID: 33684392 DOI: 10.1016/j.yexmp.2021.104622] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 02/15/2021] [Accepted: 03/03/2021] [Indexed: 12/01/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by neuronal and synaptic loss. The cytoplasmic tail of amyloid precursor protein (APP) undergoes sequential cleavage at a specific intracellular caspase site to generate the cytoplasmic terminal 31 (CT31) fragment. The APP-CT31 fragment is a potent inducer of apoptosis. The cytotoxicity of APP-CT31 in SH-SY5Y cells was evaluated by the lactate dehydrogenase (LDH) assay. TUNEL staining was used to detect apoptotic signals in SH-SY5Y cells and primary cortical neurons. The expression of apoptosis-related proteins, such as p53, PUMA (p53 up-regulated modulator of apoptosis), and cleaved was investigated by immunofluorescence analysis and Western blotting. In this study, we investigated the neuroprotective effect of neuregulin 1 (NRG1) against cytotoxicity induced by APP-CT31. Our data showed that CT31 induced cytotoxicity and apoptosis in SH-SY5Y cells and primary cortical neurons. NRG1 attenuated the neurotoxicity induced by the expression of APP-CT31. We also showed that APP-CT31 altered the expression of p53 and cleaved caspase 3. However, treatment with NRG1 rescued the APP-CT31-induced upregulation of p53 and cleaved caspase 3 expression. The protective effect of NRG1 was abrogated by inhibition of the ErbB4 receptor and Akt. These results indicate an important role of ErbB4/Akt signaling in NRG1-mediated neuroprotection, suggesting that endogenous NRG1/ErbB4 signaling represents a valuable therapeutic target in AD.
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Affiliation(s)
- Ji-Young Yoo
- Department of Anatomy and Neuroscience, College of Medicine, Eulji University, Daejeon 301-746, Republic of Korea
| | - Han-Byeol Kim
- Department of Anatomy and Neuroscience, College of Medicine, Eulji University, Daejeon 301-746, Republic of Korea
| | - Tai-Kyoung Baik
- Department of Anatomy and Neuroscience, College of Medicine, Eulji University, Daejeon 301-746, Republic of Korea
| | - Jun-Ho Lee
- Department of Emergency Medical Technology, Daejeon University, Daejeon 34520, Republic of Korea.
| | - Ran-Sook Woo
- Department of Anatomy and Neuroscience, College of Medicine, Eulji University, Daejeon 301-746, Republic of Korea.
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Puzzo D, Argyrousi EK, Staniszewski A, Zhang H, Calcagno E, Zuccarello E, Acquarone E, Fa' M, Li Puma DD, Grassi C, D'Adamio L, Kanaan NM, Fraser PE, Arancio O. Tau is not necessary for amyloid-β-induced synaptic and memory impairments. J Clin Invest 2021; 130:4831-4844. [PMID: 32544084 DOI: 10.1172/jci137040] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 06/10/2020] [Indexed: 12/20/2022] Open
Abstract
The amyloid hypothesis posits that the amyloid-beta (Aβ) protein precedes and requires microtubule-associated protein tau in a sort of trigger-bullet mechanism leading to Alzheimer's disease (AD) pathology. This sequence of events has become dogmatic in the AD field and is used to explain clinical trial failures due to a late start of the intervention when Aβ already activated tau. Here, using a multidisciplinary approach combining molecular biological, biochemical, histopathological, electrophysiological, and behavioral methods, we demonstrated that tau suppression did not protect against Aβ-induced damage of long-term synaptic plasticity and memory, or from amyloid deposition. Tau suppression could even unravel a defect in basal synaptic transmission in a mouse model of amyloid deposition. Similarly, tau suppression did not protect against exogenous oligomeric tau-induced impairment of long-term synaptic plasticity and memory. The protective effect of tau suppression was, in turn, confined to short-term plasticity and memory. Taken together, our data suggest that therapies downstream of Aβ and tau together are more suitable to combat AD than therapies against one or the other alone.
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Affiliation(s)
- Daniela Puzzo
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy.,Oasi Research Institute-IRCCS, Troina, Italy
| | - Elentina K Argyrousi
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, and.,Department of Medicine, Columbia University, New York, New York, USA
| | - Agnieszka Staniszewski
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, and.,Department of Medicine, Columbia University, New York, New York, USA
| | - Hong Zhang
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, and.,Department of Medicine, Columbia University, New York, New York, USA
| | - Elisa Calcagno
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, and.,Department of Medicine, Columbia University, New York, New York, USA
| | - Elisa Zuccarello
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, and.,Department of Medicine, Columbia University, New York, New York, USA
| | - Erica Acquarone
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, and.,Department of Medicine, Columbia University, New York, New York, USA
| | - Mauro Fa'
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, and.,Department of Medicine, Columbia University, New York, New York, USA
| | - Domenica D Li Puma
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico A. Gemelli-IRCCS, Rome, Italy
| | - Claudio Grassi
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico A. Gemelli-IRCCS, Rome, Italy
| | - Luciano D'Adamio
- Department of Pharmacology, Physiology and Neuroscience, Rutgers University, Newark, New Jersey, USA
| | - Nicholas M Kanaan
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA
| | - Paul E Fraser
- Tanz Centre for Research in Neurodegenerative Diseases, and.,Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Ottavio Arancio
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, and.,Department of Medicine, Columbia University, New York, New York, USA
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11
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Javed I, Zhang Z, Adamcik J, Andrikopoulos N, Li Y, Otzen DE, Lin S, Mezzenga R, Davis TP, Ding F, Ke PC. Accelerated Amyloid Beta Pathogenesis by Bacterial Amyloid FapC. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2001299. [PMID: 32999841 PMCID: PMC7509637 DOI: 10.1002/advs.202001299] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/10/2020] [Indexed: 05/03/2023]
Abstract
The gut-brain axis has attracted increasing attention in recent years, fueled by accumulating symptomatic, physiological, and pathological findings. In this study, the aggregation and toxicity of amyloid beta (Aβ), the pathogenic peptide associated with Alzheimer's disease (AD), seeded by FapC amyloid fragments (FapCS) of Pseudomonas aeruginosa that colonizes the gut microbiome through infections are examined. FapCS display favorable binding with Aβ and a catalytic capacity in seeding the peptide amyloidosis. Upon seeding, twisted Aβ fibrils assume a much-shortened periodicity approximating that of FapC fibrils, accompanied by a 37% sharp rise in the fibrillar diameter, compared with the control. The robust seeding capacity for Aβ by FapCS and the biofilm fragments derived from P. aeruginosa entail abnormal behavior pathology and immunohistology, as well as impaired cognitive function of zebrafish. Together, the data offer the first concrete evidence of structural integration and inheritance in peptide cross-seeding, a crucial knowledge gap in understanding the pathological correlations between different amyloid diseases. The catalytic role of infectious bacteria in promoting Aβ amyloidosis may be exploited as a potential therapeutic target, while the altered mesoscopic signatures of Aβ fibrils may serve as a prototype for molecular assembly and a biomarker for screening bacterial infections in AD.
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Affiliation(s)
- Ibrahim Javed
- Australian Institute for Bioengineering and NanotechnologyUniversity of QueenslandBrisbaneQLD4072Australia
- ARC Centre of Excellence in Convergent Bio‐Nano Science and TechnologyMonash Institute of Pharmaceutical SciencesMonash University381 Royal ParadeParkvilleVIC3052Australia
| | - Zhenzhen Zhang
- Department of Physics and AstronomyClemson UniversityClemsonSC29634USA
| | - Jozef Adamcik
- Food & Soft MaterialsDepartment of Health Science & TechnologyETH ZurichSchmelzbergstrasse 9, LFO, E23Zurich8092Switzerland
| | - Nicholas Andrikopoulos
- ARC Centre of Excellence in Convergent Bio‐Nano Science and TechnologyMonash Institute of Pharmaceutical SciencesMonash University381 Royal ParadeParkvilleVIC3052Australia
| | - Yuhuan Li
- ARC Centre of Excellence in Convergent Bio‐Nano Science and TechnologyMonash Institute of Pharmaceutical SciencesMonash University381 Royal ParadeParkvilleVIC3052Australia
| | - Daniel E. Otzen
- Interdisciplinary Nanoscience Center (iNANO)University of AarhusAarhus CAarhus8000Denmark
| | - Sijie Lin
- College of Environmental Science and EngineeringBiomedical Multidisciplinary Innovation Research InstituteShanghai East HospitalShanghai Institute of Pollution Control and Ecological SecurityTongji University1239 Siping RoadShanghai200092China
| | - Raffaele Mezzenga
- Food & Soft MaterialsDepartment of Health Science & TechnologyETH ZurichSchmelzbergstrasse 9, LFO, E23Zurich8092Switzerland
| | - Thomas P. Davis
- Australian Institute for Bioengineering and NanotechnologyUniversity of QueenslandBrisbaneQLD4072Australia
- ARC Centre of Excellence in Convergent Bio‐Nano Science and TechnologyMonash Institute of Pharmaceutical SciencesMonash University381 Royal ParadeParkvilleVIC3052Australia
| | - Feng Ding
- Department of Physics and AstronomyClemson UniversityClemsonSC29634USA
| | - Pu Chun Ke
- ARC Centre of Excellence in Convergent Bio‐Nano Science and TechnologyMonash Institute of Pharmaceutical SciencesMonash University381 Royal ParadeParkvilleVIC3052Australia
- Zhongshan HospitalFudan University111 Yixueyuan Rd, Xuhui DistrictShanghai200032China
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12
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Chatzistavraki M, Papazafiri P, Efthimiopoulos S. Amyloid-β Protein Precursor Regulates Depolarization-Induced Calcium-Mediated Synaptic Signaling in Brain Slices. J Alzheimers Dis 2020; 76:1121-1133. [PMID: 32597808 DOI: 10.3233/jad-200290] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Coordinated calcium influx upon neuronal depolarization activates pathways that phosphorylate CaMKII, ERKs, and the transcription factor CREB and, therefore, expression of pro-survival and neuroprotective genes. Recent evidence indicates that amyloid-β protein precursor (AβPP) is trafficked to synapses and promotes their formation. At the synapse, AβPP interacts with synaptic proteins involved in vesicle exocytosis and affects calcium channel function. OBJECTIVE Herein, we examined the role of AβPP in depolarization-induced calcium-mediated signaling using acute cerebral slices from wild-type C57bl/6 mice and AβPP-/- C57bl/6 mice. METHODS Depolarization of acute cerebral slices from wild-type C57bl/6 and AβPP-/- C57bl/6 mice was used to induce synaptic signaling. Protein levels were examined by western blot and calcium dynamics were assessed using primary neuronal cultures. RESULTS In the absence of AβPP, decreased pCaMKII and pERKs levels were observed. This decrease was sensitive to the inhibition of N- and P/Q-type Voltage Gated Calcium Channels (N- and P/Q-VGCCs) by ω-conotoxin GVIA and ω-conotoxin MVIIC, respectively, but not to inhibition of L-type VGCCs by nifedipine. However, the absence of AβPP did not result in a statistically significant decrease of pCREB, which is a known substrate of pERKs. Finally, using calcium imaging, we found that down regulation of AβPP in cortical neurons results in a decreased response to depolarization and altered kinetics of calcium response. CONCLUSION AβPP regulates synaptic activity-mediated neuronal signaling by affecting N- and P/Q-VGCCs.
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Affiliation(s)
- Maria Chatzistavraki
- Department of Biology, Division of Animal and Human Physiology, National and Kapodistrian University of Athens, Panepistimiopolis, Ilisia, Greece
| | - Panagiota Papazafiri
- Department of Biology, Division of Animal and Human Physiology, National and Kapodistrian University of Athens, Panepistimiopolis, Ilisia, Greece
| | - Spiros Efthimiopoulos
- Department of Biology, Division of Animal and Human Physiology, National and Kapodistrian University of Athens, Panepistimiopolis, Ilisia, Greece
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13
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Salvianolic Acid B improves cognitive impairment by inhibiting neuroinflammation and decreasing Aβ level in Porphyromonas gingivalis-infected mice. Aging (Albany NY) 2020; 12:10117-10128. [PMID: 32516126 PMCID: PMC7346047 DOI: 10.18632/aging.103306] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 04/17/2020] [Indexed: 12/14/2022]
Abstract
Amyloid-β (Aβ) accumulation is one of the main pathological hallmarks of Alzheimer’s disease (AD). Porphyromonas gingivalis (P. gingivalis), the pathogen of chronic periodontitis, could cause Aβ accumulation and was identified in the brain of AD patients. Salvianolic Acid B (SalB) has been proven to have the neuroprotective effect. Whether SalB could protect against P. gingivalis-induced cognitive impairment is still unknown. In this study, a P. gingivalis-infected mouse model was employed to study the neuroprotective role of SalB. The results showed that SalB (20 and 40 mg/kg) treatment for 4 weeks could shorten the escape latency and improve the percentage of spontaneous alternation in the P. gingivalis-infected mice. SalB inhibited the levels of reactive oxygen species and malondialdehyde, while increased the levels of antioxidative enzymes (superoxide dismutase and glutathione peroxidase). SalB decreased the levels of IL-1β and IL-6, increased the mRNA levels of bdnf and ngf in the brain of P. gingivalis-infected mice. In addition, SalB obviously decreased the level of Aβ. SalB elevated the protein expression of ADAM10, while downregulated BACE1 and PS1. SalB increased the protein expression of LRP1, while decreased RAGE. In conclusion, SalB could improve cognitive impairment by inhibiting neuroinflammation and decreasing Aβ level in P. gingivalis-infected mice.
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Effect of Aβ Oligomers on Neuronal APP Triggers a Vicious Cycle Leading to the Propagation of Synaptic Plasticity Alterations to Healthy Neurons. J Neurosci 2020; 40:5161-5176. [PMID: 32444385 DOI: 10.1523/jneurosci.2501-19.2020] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 03/04/2020] [Accepted: 04/03/2020] [Indexed: 01/04/2023] Open
Abstract
Alterations of excitatory synaptic function are the strongest correlate to the pathologic disturbance of cognitive ability observed in the early stages of Alzheimer's disease (AD). This pathologic feature is driven by amyloid-β oligomers (Aβos) and propagates from neuron to neuron. Here, we investigated the mechanism by which Aβos affect the function of synapses and how these alterations propagate to surrounding healthy neurons. We used complementary techniques ranging from electrophysiological recordings and molecular biology to confocal microscopy in primary cortical cultures, and from acute hippocampal and cortical slices from male wild-type and amyloid precursor protein (APP) knock-out (KO) mice to assess the effects of Aβos on glutamatergic transmission, synaptic plasticity, and dendritic spine structure. We showed that extracellular application of Aβos reduced glutamatergic synaptic transmission and long-term potentiation. These alterations were not observed in APP KO neurons, suggesting that APP expression is required. We demonstrated that Aβos/APP interaction increases the amyloidogenic processing of APP leading to intracellular accumulation of newly produced Aβos. Intracellular Aβos participate in synaptic dysfunctions as shown by pharmacological inhibition of APP processing or by intraneuronal infusion of an antibody raised against Aβos. Furthermore, we provide evidence that following APP processing, extracellular release of Aβos mediates the propagation of the synaptic pathology characterized by a decreased spine density of neighboring healthy neurons in an APP-dependent manner. Together, our data unveil a complementary role for Aβos in AD, while intracellular Aβos alter synaptic function, extracellular Aβos promote a vicious cycle that propagates synaptic pathology from diseased to healthy neurons.SIGNIFICANCE STATEMENT Here we provide the proof that a vicious cycle between extracellular and intracellular pools of Aβ oligomers (Aβos) is required for the spreading of Alzheimer's disease (AD) pathology. We showed that extracellular Aβos propagate excitatory synaptic alterations by promoting amyloid precursor protein (APP) processing. Our results also suggest that subsequent to APP cleavage two pools of Aβos are produced. One pool accumulates inside the cytosol, inducing the loss of synaptic plasticity potential. The other pool is released into the extracellular space and contributes to the propagation of the pathology from diseased to healthy neurons. Pharmacological strategies targeting the proteolytic cleavage of APP disrupt the relationship between extracellular and intracellular Aβ, providing a therapeutic approach for the disease.
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15
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Gulisano W, Melone M, Ripoli C, Tropea MR, Li Puma DD, Giunta S, Cocco S, Marcotulli D, Origlia N, Palmeri A, Arancio O, Conti F, Grassi C, Puzzo D. Neuromodulatory Action of Picomolar Extracellular Aβ42 Oligomers on Presynaptic and Postsynaptic Mechanisms Underlying Synaptic Function and Memory. J Neurosci 2019; 39:5986-6000. [PMID: 31127002 PMCID: PMC6650983 DOI: 10.1523/jneurosci.0163-19.2019] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 04/09/2019] [Accepted: 04/28/2019] [Indexed: 01/01/2023] Open
Abstract
Failure of anti-amyloid-β peptide (Aβ) therapies against Alzheimer's disease (AD), a neurodegenerative disorder characterized by high amounts of the peptide in the brain, raised the question of the physiological role of Aβ released at low concentrations in the healthy brain. To address this question, we studied the presynaptic and postsynaptic mechanisms underlying the neuromodulatory action of picomolar amounts of oligomeric Aβ42 (oAβ42) on synaptic glutamatergic function in male and female mice. We found that 200 pm oAβ42 induces an increase of frequency of miniature EPSCs and a decrease of paired pulse facilitation, associated with an increase in docked vesicle number, indicating that it augments neurotransmitter release at presynaptic level. oAβ42 also produced postsynaptic changes as shown by an increased length of postsynaptic density, accompanied by an increased expression of plasticity-related proteins such as cAMP-responsive element binding protein phosphorylated at Ser133, calcium-calmodulin-dependent kinase II phosphorylated at Thr286, and brain-derived neurotrophic factor, suggesting a role for Aβ in synaptic tagging. These changes resulted in the conversion of early into late long-term potentiation through the nitric oxide/cGMP/protein kinase G intracellular cascade consistent with a cGMP-dependent switch from short- to long-term memory observed in vivo after intrahippocampal administration of picomolar amounts of oAβ42 These effects were present upon extracellular but not intracellular application of the peptide and involved α7 nicotinic acetylcholine receptors. These observations clarified the physiological role of oAβ42 in synaptic function and memory formation providing solid fundamentals for investigating the pathological effects of high Aβ levels in the AD brains.SIGNIFICANCE STATEMENT High levels of oligomeric amyloid-β42 (oAβ42) induce synaptic dysfunction leading to memory impairment in Alzheimer's disease (AD). However, at picomolar concentrations, the peptide is needed to ensure long-term potentiation (LTP) and memory. Here, we show that extracellular 200 pm oAβ42 concentrations increase neurotransmitter release, number of docked vesicles, postsynaptic density length, and expression of plasticity-related proteins leading to the conversion of early LTP into late LTP and of short-term memory into long-term memory. These effects require α7 nicotinic acetylcholine receptors and are mediated through the nitric oxide/cGMP/protein kinase G pathway. The knowledge of Aβ function in the healthy brain might be useful to understand the causes leading to its increase and detrimental effect in AD.
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Affiliation(s)
- Walter Gulisano
- Department Biomedical and Biotechnological Sciences, University of Catania, Catania 95123, Italy
| | - Marcello Melone
- Section of Neuroscience and Cell Biology, Department Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona 60020, Italy
- Center for Neurobiology of Aging, IRCCS Istituto Nazionale Ricovero e Cura Anziani (INRCA), Ancona 60020, Italy
| | - Cristian Ripoli
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome 00168, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome 00168, Italy
| | - Maria Rosaria Tropea
- Department Biomedical and Biotechnological Sciences, University of Catania, Catania 95123, Italy
| | - Domenica D Li Puma
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome 00168, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome 00168, Italy
| | - Salvatore Giunta
- Department Biomedical and Biotechnological Sciences, University of Catania, Catania 95123, Italy
| | - Sara Cocco
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome 00168, Italy
| | - Daniele Marcotulli
- Section of Neuroscience and Cell Biology, Department Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona 60020, Italy
| | - Nicola Origlia
- Neuroscience Institute, Italian National Research Council, Pisa 56100, Italy
| | - Agostino Palmeri
- Department Biomedical and Biotechnological Sciences, University of Catania, Catania 95123, Italy
| | - Ottavio Arancio
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, New York 10032
| | - Fiorenzo Conti
- Section of Neuroscience and Cell Biology, Department Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona 60020, Italy
- Center for Neurobiology of Aging, IRCCS Istituto Nazionale Ricovero e Cura Anziani (INRCA), Ancona 60020, Italy
- Foundation for Molecular Medicine, Università Politecnica delle Marche, Ancona 60020, Italy, and
| | - Claudio Grassi
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome 00168, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome 00168, Italy
| | - Daniela Puzzo
- Department Biomedical and Biotechnological Sciences, University of Catania, Catania 95123, Italy,
- Oasi Research Institute-IRCCS, Troina, 94018, Italy
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16
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Matrone C, Iannuzzi F, Annunziato L. The Y 682ENPTY 687 motif of APP: Progress and insights toward a targeted therapy for Alzheimer's disease patients. Ageing Res Rev 2019; 52:120-128. [PMID: 31039414 DOI: 10.1016/j.arr.2019.04.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 03/04/2019] [Accepted: 04/10/2019] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD) is a devastating neurodegenerative disorder for which no curative treatments, disease modifying strategies or effective symptomatic therapies exist. Current pharmacologic treatments for AD can only decelerate the progression of the disease for a short time, often at the cost of severe side effects. Therefore, there is an urgent need for biomarkers able to diagnose AD at its earliest stages, to conclusively track disease progression, and to accelerate the clinical development of innovative therapies. Scientific research and economic efforts for the development of pharmacotherapies have recently homed in on the hypothesis that neurotoxic β-amyloid (Aβ) peptides in their oligomeric or fibrillary forms are primarily responsible for the cognitive impairment and neuronal death seen in AD. As such, modern pharmacologic approaches are largely based on reducing production by inhibiting β and γ secretase cleavage of the amyloid precursor protein (APP) or on dissolving existing cerebral Aβ plaques or to favor Aβ clearance from the brain. The following short review aims to persuade the reader of the idea that APP plays a much larger role in AD pathogenesis. APP plays a greater role in AD pathogenesis than its role as the precursor for Aβ peptides: both the abnormal cleavage of APP leading to Aβ peptide accumulation and the disruption of APP physiological functions contribute to AD pathogenesis. We summarize our recent results on the role played by the C-terminal APP motif -the Y682ENPTY68 motif- in APP function and dysfunction, and we provide insights into targeting the Tyr682 residue of APP as putative novel strategy in AD.
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17
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Acquarone E, Argyrousi EK, van den Berg M, Gulisano W, Fà M, Staniszewski A, Calcagno E, Zuccarello E, D’Adamio L, Deng SX, Puzzo D, Arancio O, Fiorito J. Synaptic and memory dysfunction induced by tau oligomers is rescued by up-regulation of the nitric oxide cascade. Mol Neurodegener 2019; 14:26. [PMID: 31248451 PMCID: PMC6598340 DOI: 10.1186/s13024-019-0326-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 06/05/2019] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Soluble aggregates of oligomeric forms of tau protein (oTau) have been associated with impairment of synaptic plasticity and memory in Alzheimer's disease. However, the molecular mechanisms underlying the synaptic and memory dysfunction induced by elevation of oTau are still unknown. METHODS This work used a combination of biochemical, electrophysiological and behavioral techniques. Biochemical methods included analysis of phosphorylation of the cAMP-responsive element binding (CREB) protein, a transcriptional factor involved in memory, histone acetylation, and expression immediate early genes c-Fos and Arc. Electrophysiological methods included assessment of long-term potentiation (LTP), a type of synaptic plasticity thought to underlie memory formation. Behavioral studies investigated both short-term spatial memory and associative memory. These phenomena were examined following oTau elevation. RESULTS Levels of phospho-CREB, histone 3 acetylation at lysine 27, and immediate early genes c-Fos and Arc, were found to be reduced after oTau elevation during memory formation. These findings led us to explore whether up-regulation of various components of the nitric oxide (NO) signaling pathway impinging onto CREB is capable of rescuing oTau-induced impairment of plasticity, memory, and CREB phosphorylation. The increase of NO levels protected against oTau-induced impairment of LTP through activation of soluble guanylyl cyclase. Similarly, the elevation of cGMP levels and stimulation of the cGMP-dependent protein kinases (PKG) re-established normal LTP after exposure to oTau. Pharmacological inhibition of cGMP degradation through inhibition of phosphodiesterase 5 (PDE5), rescued oTau-induced LTP reduction. These findings could be extrapolated to memory because PKG activation and PDE5 inhibition rescued oTau-induced memory impairment. Finally, PDE5 inhibition re-established normal elevation of CREB phosphorylation and cGMP levels after memory induction in the presence of oTau. CONCLUSIONS Up-regulation of CREB activation through agents acting on the NO cascade might be beneficial against tau-induced synaptic and memory dysfunctions.
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Affiliation(s)
- Erica Acquarone
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S 12-420D, New York, NY 10032 USA
- DiMi Department of Internal Medicine and Medical Specialties, University of Genoa, 16132 Genoa, Italy
| | - Elentina K. Argyrousi
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S 12-420D, New York, NY 10032 USA
- Faculty of Psychology and Neuroscience, Maastricht University, 6229 Maastricht, Netherlands
| | - Manon van den Berg
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S 12-420D, New York, NY 10032 USA
- Faculty of Psychology and Neuroscience, Maastricht University, 6229 Maastricht, Netherlands
| | - Walter Gulisano
- Department of Biomedical and Biotechnological Sciences, Section of Physiology, University of Catania, 95125 Catania, Italy
| | - Mauro Fà
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S 12-420D, New York, NY 10032 USA
| | - Agnieszka Staniszewski
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S 12-420D, New York, NY 10032 USA
| | - Elisa Calcagno
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S 12-420D, New York, NY 10032 USA
- Department of Experimental Medicine, Section of General Pathology, School of Medical and Pharmaceutical Sciences, University of Genoa, 16132 Genoa, Italy
| | - Elisa Zuccarello
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S 12-420D, New York, NY 10032 USA
| | - Luciano D’Adamio
- Department of Pharmacology, Physiology and Neuroscience, Rutgers University, Newark, NJ USA
| | - Shi-Xian Deng
- Department of Medicine, Columbia University, New York, NY 10032 USA
| | - Daniela Puzzo
- Department of Biomedical and Biotechnological Sciences, Section of Physiology, University of Catania, 95125 Catania, Italy
- Oasi Research Institute-IRCCS, 94018 Troina, Italy
| | - Ottavio Arancio
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S 12-420D, New York, NY 10032 USA
- Department of Medicine, Columbia University, New York, NY 10032 USA
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10032 USA
| | - Jole Fiorito
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, 630 West 168th Street, P&S 12-420D, New York, NY 10032 USA
- Department of Life Sciences, New York Institute of Technology, Northern Boulevard P.O. Box 8000, Theobald Science Center, room 425, Old Westbury, NY 11568 USA
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18
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Pantelopulos GA, Straub JE, Thirumalai D, Sugita Y. Structure of APP-C99 1-99 and implications for role of extra-membrane domains in function and oligomerization. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1698-1708. [PMID: 29702072 DOI: 10.1016/j.bbamem.2018.04.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 04/07/2018] [Accepted: 04/09/2018] [Indexed: 01/30/2023]
Abstract
The 99 amino acid C-terminal fragment of Amyloid Precursor Protein APP-C99 (C99) is cleaved by γ-secretase to form Aβ peptide, which plays a critical role in the etiology of Alzheimer's Disease (AD). The structure of C99 consists of a single transmembrane domain flanked by intra and intercellular domains. While the structure of the transmembrane domain has been well characterized, little is known about the structure of the flanking domains and their role in C99 processing by γ-secretase. To gain insight into the structure of full-length C99, REMD simulations were performed for monomeric C99 in model membranes of varying thickness. We find equilibrium ensembles of C99 from simulation agree with experimentally-inferred residue insertion depths and protein backbone chemical shifts. In thin membranes, the transmembrane domain structure is correlated with extra-membrane structural states and the extra-membrane domain structural states become less correlated to each other. Mean and variance of the transmembrane and G37G38 hinge angles are found to increase with thinning membrane. The N-terminus of C99 forms β-strands that may seed aggregation of Aβ on the membrane surface, promoting amyloid formation. In thicker membranes the N-terminus forms α-helices that interact with the nicastrin domain of γ-secretase. The C-terminus of C99 becomes more α-helical as the membrane thickens, forming structures that may be suitable for binding by cytoplasmic proteins, while C-terminal residues essential to cytotoxic function become α-helical as the membrane thins. The heterogeneous but discrete extra-membrane domain states analyzed here open the path to new investigations of the role of C99 structure and membrane in amyloidogenesis. This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.
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Affiliation(s)
- George A Pantelopulos
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, MA 02215-2521, USA
| | - John E Straub
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, MA 02215-2521, USA.
| | - D Thirumalai
- Department of Chemistry, The University of Texas, Austin, TX 78712-1224, USA
| | - Yuji Sugita
- Theoretical Molecular Science Laboratory, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
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19
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Willén K, Sroka A, Takahashi RH, Gouras GK. Heterogeneous Association of Alzheimer's Disease-Linked Amyloid-β and Amyloid-β Protein Precursor with Synapses. J Alzheimers Dis 2018; 60:511-524. [PMID: 28869466 PMCID: PMC5611798 DOI: 10.3233/jad-170262] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Alzheimer’s disease (AD) is increasingly viewed as a disease of synapses. Loss of synapses correlates better with cognitive decline than amyloid plaques and neurofibrillary tangles, the hallmark neuropathological lesions of AD. Soluble forms of amyloid-β (Aβ) have emerged as mediators of synapse dysfunction. Aβ binds to, accumulates, and aggregates in synapses. However, the anatomical and neurotransmitter specificity of Aβ and the amyloid-β protein precursor (AβPP) in AD remain poorly understood. In addition, the relative roles of Aβ and AβPP in the development of AD, at pre- versus post-synaptic compartments and axons versus dendrites, respectively, remain unclear. Here we use immunogold electron microscopy and confocal microscopy to provide evidence for heterogeneity in the localization of Aβ/AβPP. We demonstrate that Aβ binds to a subset of synapses in cultured neurons, with preferential binding to glutamatergic compared to GABAergic neurons. We also highlight the challenge of defining pre- versus post-synaptic localization of this binding by confocal microscopy. Further, endogenous Aβ42 accumulates in both glutamatergic and GABAergic AβPP/PS1 transgenic primary neurons, but at varying levels. Moreover, upon knock-out of presenilin 1 or inhibition of γ-secretase AβPP C-terminal fragments accumulate both pre- and post-synaptically; however earlier pre-synaptically, consistent with a higher rate of AβPP processing in axons. A better understanding of the synaptic and anatomical selectivity of Aβ/AβPP in AD can be important for the development of more effective new therapies for this major disease of aging.
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Affiliation(s)
- Katarina Willén
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Agnieszka Sroka
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | | | - Gunnar K Gouras
- Department of Experimental Medical Science, Lund University, Lund, Sweden
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20
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Ruiz-Riquelme A, Lau HHC, Stuart E, Goczi AN, Wang Z, Schmitt-Ulms G, Watts JC. Prion-like propagation of β-amyloid aggregates in the absence of APP overexpression. Acta Neuropathol Commun 2018; 6:26. [PMID: 29615128 PMCID: PMC5883524 DOI: 10.1186/s40478-018-0529-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 03/21/2018] [Indexed: 11/10/2022] Open
Abstract
The amyloid cascade hypothesis posits that the initiating event in Alzheimer's disease (AD) is the aggregation and deposition of the β-amyloid (Aβ) peptide, which is a proteolytic cleavage product of the amyloid precursor protein (APP). Mounting evidence suggests that the formation and spread of prion-like Aβ aggregates during AD may contribute to disease progression. Inoculation of transgenic mice that overexpress APP with pre-formed Aβ aggregates results in the prion-like induction of cerebral Aβ deposition. To determine whether Aβ deposition can also be induced when physiological APP levels are present in the brain, we inoculated AppNL-F mice, a knock-in model of AD that avoids potential artifacts associated with APP overexpression, with Aβ aggregates derived from the brains of AD patients or transgenic mice. In all cases, induced Aβ deposition was apparent in the corpus callosum, olfactory bulb, and meningeal blood vessels of inoculated mice at 130-150 days post-inoculation, whereas uninoculated and buffer-inoculated animals exhibited minimal or no Aβ deposits at these ages. Interestingly, despite being predominantly composed of protease-resistant Aβ42 aggregates, the induced parenchymal Aβ deposits were largely diffuse and were unreactive to an amyloid-binding dye. These results demonstrate that APP overexpression is not a prerequisite for the prion-like induction of cerebral Aβ deposition. Accordingly, spreading of Aβ deposition may contribute to disease progression in AD patients.
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21
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Oropesa-Nuñez R, Seghezza S, Dante S, Diaspro A, Cascella R, Cecchi C, Stefani M, Chiti F, Canale C. Interaction of toxic and non-toxic HypF-N oligomers with lipid bilayers investigated at high resolution with atomic force microscopy. Oncotarget 2018; 7:44991-45004. [PMID: 27391440 PMCID: PMC5216700 DOI: 10.18632/oncotarget.10449] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 06/26/2016] [Indexed: 11/25/2022] Open
Abstract
Protein misfolded oligomers are considered the most toxic species amongst those formed in the process of amyloid formation and the molecular basis of their toxicity, although not completely understood, is thought to originate from the interaction with the cellular membrane. Here, we sought to highlight the molecular determinants of oligomer-membrane interaction by atomic force microscopy. We monitored the interaction between multiphase supported lipid bilayers and two types of HypF-N oligomers displaying different structural features and cytotoxicities. By our approach we imaged with unprecedented resolution the ordered and disordered lipid phases of the bilayer and different oligomer structures interacting with either phase. We identified the oligomers and lipids responsible for toxicity and, more generally, we established the importance of the membrane lipid component in mediating oligomer toxicity. Our findings support the importance of GM1 ganglioside in mediating the oligomer-bilayer interaction and support a mechanism of oligomer cytotoxicity involving bilayer destabilization by globular oligomers within GM1-rich ordered raft regions rather than by annular oligomers in the surrounding disordered membrane domains.
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Affiliation(s)
- Reinier Oropesa-Nuñez
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy.,DIBRIS Department, University of Genova, Genova, Italy
| | - Silvia Seghezza
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Silvia Dante
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Alberto Diaspro
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy.,Department of Physics, University of Genova, Genova, Italy
| | - Roberta Cascella
- Section of Biochemistry, Department of Biomedical Experimental and Clinical Sciences, University of Florence, Firenze, Italy
| | - Cristina Cecchi
- Section of Biochemistry, Department of Biomedical Experimental and Clinical Sciences, University of Florence, Firenze, Italy
| | - Massimo Stefani
- Section of Biochemistry, Department of Biomedical Experimental and Clinical Sciences, University of Florence, Firenze, Italy
| | - Fabrizio Chiti
- Section of Biochemistry, Department of Biomedical Experimental and Clinical Sciences, University of Florence, Firenze, Italy
| | - Claudio Canale
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
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22
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Gulisano W, Maugeri D, Baltrons MA, Fà M, Amato A, Palmeri A, D’Adamio L, Grassi C, Devanand D, Honig LS, Puzzo D, Arancio O. Role of Amyloid-β and Tau Proteins in Alzheimer's Disease: Confuting the Amyloid Cascade. J Alzheimers Dis 2018; 64:S611-S631. [PMID: 29865055 PMCID: PMC8371153 DOI: 10.3233/jad-179935] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The "Amyloid Cascade Hypothesis" has dominated the Alzheimer's disease (AD) field in the last 25 years. It posits that the increase of amyloid-β (Aβ) is the key event in AD that triggers tau pathology followed by neuronal death and eventually, the disease. However, therapeutic approaches aimed at decreasing Aβ levels have so far failed, and tau-based clinical trials have not yet produced positive findings. This begs the question of whether the hypothesis is correct. Here we have examined literature on the role of Aβ and tau in synaptic dysfunction, memory loss, and seeding and spreading of AD, highlighting important parallelisms between the two proteins in all of these phenomena. We discuss novel findings showing binding of both Aβ and tau oligomers to amyloid-β protein precursor (AβPP), and the requirement for the presence of this protein for both Aβ and tau to enter neurons and induce abnormal synaptic function and memory. Most importantly, we propose a novel view of AD pathogenesis in which extracellular oligomers of Aβ and tau act in parallel and upstream of AβPP. Such a view will call for a reconsideration of therapeutic approaches directed against Aβ and tau, paving the way to an increased interest toward AβPP, both for understanding the pathogenesis of the disease and elaborating new therapeutic strategies.
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Affiliation(s)
- Walter Gulisano
- Department of Biomedical and Biotechnological Sciences, Section of Physiology, University of Catania, Catania, Italy
| | - Daniele Maugeri
- Department of Biomedical and Biotechnological Sciences, Section of Physiology, University of Catania, Catania, Italy
| | - Marian A. Baltrons
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, USA
- Department of Biochemistry and Molecular Biology and Institute of Biotechnology and Biomedicine, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Mauro Fà
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, USA
| | - Arianna Amato
- Department of Anaesthesiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Agostino Palmeri
- Department of Biomedical and Biotechnological Sciences, Section of Physiology, University of Catania, Catania, Italy
| | - Luciano D’Adamio
- Department of Pharmacology, Physiology and Neuroscience, Rutgers University, Newark, NJ, USA
| | - Claudio Grassi
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - D.P. Devanand
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, USA
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Lawrence S. Honig
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, USA
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Daniela Puzzo
- Department of Biomedical and Biotechnological Sciences, Section of Physiology, University of Catania, Catania, Italy
| | - Ottavio Arancio
- Department of Pathology and Cell Biology, Columbia University, New York, NY, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, USA
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23
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Bignante EA, Ponce NE, Heredia F, Musso J, Krawczyk MC, Millán J, Pigino GF, Inestrosa NC, Boccia MM, Lorenzo A. APP/Go protein Gβγ-complex signaling mediates Aβ degeneration and cognitive impairment in Alzheimer's disease models. Neurobiol Aging 2017; 64:44-57. [PMID: 29331876 DOI: 10.1016/j.neurobiolaging.2017.12.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 12/05/2017] [Accepted: 12/10/2017] [Indexed: 11/15/2022]
Abstract
Deposition of amyloid-β (Aβ), the proteolytic product of the amyloid precursor protein (APP), might cause neurodegeneration and cognitive decline in Alzheimer's disease (AD). However, the direct involvement of APP in the mechanism of Aβ-induced degeneration in AD remains on debate. Here, we analyzed the interaction of APP with heterotrimeric Go protein in primary hippocampal cultures and found that Aβ deposition dramatically enhanced APP-Go protein interaction in dystrophic neurites. APP overexpression rendered neurons vulnerable to Aβ toxicity by a mechanism that required Go-Gβγ complex signaling and p38-mitogen-activated protein kinase activation. Gallein, a selective pharmacological inhibitor of Gβγ complex, inhibited Aβ-induced dendritic and axonal dystrophy, abnormal tau phosphorylation, synaptic loss, and neuronal cell death in hippocampal neurons expressing endogenous protein levels. In the 3xTg-AD mice, intrahippocampal application of gallein reversed memory impairment associated with early Aβ pathology. Our data provide further evidence for the involvement of APP/Go protein in Aβ-induced degeneration and reveal that Gβγ complex is a signaling target potentially relevant for developing therapies for halting Aβ degeneration in AD.
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Affiliation(s)
- Elena Anahi Bignante
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina; Instituto Universitario de Ciencias Biomédicas de Córdoda (IUCBC), Argentina
| | - Nicolás Eric Ponce
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Florencia Heredia
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Juliana Musso
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina
| | - María C Krawczyk
- Laboratorio de Neurofarmacología de los Procesos de Memoria, Cátedra de Farmacología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Julieta Millán
- Laboratorio de Neurofarmacología de los Procesos de Memoria, Cátedra de Farmacología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Gustavo F Pigino
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Nibaldo C Inestrosa
- Centro de Envejecimiento y Regeneración (CARE), Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile; Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Punta Arenas, Chile
| | - Mariano M Boccia
- Laboratorio de Neurofarmacología de los Procesos de Memoria, Cátedra de Farmacología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Alfredo Lorenzo
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina; Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina.
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24
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IL4/STAT6 Signaling Activates Neural Stem Cell Proliferation and Neurogenesis upon Amyloid-β42 Aggregation in Adult Zebrafish Brain. Cell Rep 2017; 17:941-948. [PMID: 27760324 DOI: 10.1016/j.celrep.2016.09.075] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 06/25/2016] [Accepted: 09/22/2016] [Indexed: 12/12/2022] Open
Abstract
Human brains are prone to neurodegeneration, given that endogenous neural stem/progenitor cells (NSPCs) fail to support neurogenesis. To investigate the molecular programs potentially mediating neurodegeneration-induced NSPC plasticity in regenerating organisms, we generated an Amyloid-β42 (Aβ42)-dependent neurotoxic model in adult zebrafish brain through cerebroventricular microinjection of cell-penetrating Aβ42 derivatives. Aβ42 deposits in neurons and causes phenotypes reminiscent of amyloid pathophysiology: apoptosis, microglial activation, synaptic degeneration, and learning deficits. Aβ42 also induces NSPC proliferation and enhanced neurogenesis. Interleukin-4 (IL4) is activated primarily in neurons and microglia/macrophages in response to Aβ42 and is sufficient to increase NSPC proliferation and neurogenesis via STAT6 phosphorylation through the IL4 receptor in NSPCs. Our results reveal a crosstalk between neurons and immune cells mediated by IL4/STAT6 signaling, which induces NSPC plasticity in zebrafish brains.
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25
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Human Brain-Derived Aβ Oligomers Bind to Synapses and Disrupt Synaptic Activity in a Manner That Requires APP. J Neurosci 2017; 37:11947-11966. [PMID: 29101243 DOI: 10.1523/jneurosci.2009-17.2017] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 09/19/2017] [Accepted: 09/29/2017] [Indexed: 12/20/2022] Open
Abstract
Compelling genetic evidence links the amyloid precursor protein (APP) to Alzheimer's disease (AD) and several theories have been advanced to explain the relationship. A leading hypothesis proposes that a small amphipathic fragment of APP, the amyloid β-protein (Aβ), self-associates to form soluble aggregates that impair synaptic and network activity. Here, we used the most disease-relevant form of Aβ, protein isolated from AD brain. Using this material, we show that the synaptotoxic effects of Aβ depend on expression of APP and that the Aβ-mediated impairment of synaptic plasticity is accompanied by presynaptic effects that disrupt the excitatory/inhibitory (E/I) balance. The net increase in the E/I ratio and inhibition of plasticity are associated with Aβ localizing to synapses and binding of soluble Aβ aggregates to synapses requires the expression of APP. Our findings indicate a role for APP in AD pathogenesis beyond the generation of Aβ and suggest modulation of APP expression as a therapy for AD.SIGNIFICANCE STATEMENT Here, we report on the plasticity-disrupting effects of amyloid β-protein (Aβ) isolated from Alzheimer's disease (AD) brain and the requirement of amyloid precursor protein (APP) for these effects. We show that Aβ-containing AD brain extracts block hippocampal LTP, augment glutamate release probability, and disrupt the excitatory/inhibitory balance. These effects are associated with Aβ localizing to synapses and genetic ablation of APP prevents both Aβ binding and Aβ-mediated synaptic dysfunctions. Our results emphasize the importance of APP in AD and should stimulate new studies to elucidate APP-related targets suitable for pharmacological manipulation.
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26
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Angulo SL, Orman R, Neymotin SA, Liu L, Buitrago L, Cepeda-Prado E, Stefanov D, Lytton WW, Stewart M, Small SA, Duff KE, Moreno H. Tau and amyloid-related pathologies in the entorhinal cortex have divergent effects in the hippocampal circuit. Neurobiol Dis 2017; 108:261-276. [PMID: 28860088 DOI: 10.1016/j.nbd.2017.08.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 08/09/2017] [Accepted: 08/26/2017] [Indexed: 02/02/2023] Open
Abstract
The entorhinal cortex (EC) is affected early in Alzheimer's disease, an illness defined by a co-occurrence of tau and amyloid-related pathologies. How the co-occurrence of these pathologies in the EC affects the hippocampal circuit remains unknown. Here we address this question by performing electrophysiological analyses of the EC circuit in mice that express mutant human amyloid precursor protein (hAPP) or tau (hTau), or both in the EC. We show that the alterations in the hippocampal circuit are divergent, with hAPP increasing but hTau decreasing neuronal/circuit excitability. Most importantly, mice co-expressing hAPP and hTau show that hTau has a dominant effect, dampening the excitatory effects of hAPP. Additionally, compensatory synaptic downscaling, in response to increased excitability in EC was observed in subicular neurons of hAPP mice. Based on simulations, we propose that EC interneuron pruning can account for both EC hyperexcitability and subicular synaptic downscaling found in mice expressing hAPP.
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Affiliation(s)
- S L Angulo
- Department of Neurology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States; The Robert F. Furchgott Center for Neural and Behavioral Science, Department of Physiology/Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States
| | - R Orman
- The Robert F. Furchgott Center for Neural and Behavioral Science, Department of Physiology/Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States
| | - S A Neymotin
- Department of Neuroscience, Brown University, Providence, RI 02912, United States
| | - L Liu
- Department of Pathology, Cell Biology, Columbia University Medical Center, NY 10032, United States; Department of Psychiatry, Columbia University Medical Center, NY 10032, United States
| | - L Buitrago
- Department of Neurology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States; The Robert F. Furchgott Center for Neural and Behavioral Science, Department of Physiology/Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States
| | - E Cepeda-Prado
- Department of Neurology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States; The Robert F. Furchgott Center for Neural and Behavioral Science, Department of Physiology/Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States
| | - D Stefanov
- Scientific Computer Center, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States
| | - W W Lytton
- Department of Neurology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States; The Robert F. Furchgott Center for Neural and Behavioral Science, Department of Physiology/Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States
| | - M Stewart
- The Robert F. Furchgott Center for Neural and Behavioral Science, Department of Physiology/Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States
| | - S A Small
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, NY 10032, United States; Department of Neurology, Columbia University Medical Center, NY 10032, United States
| | - K E Duff
- Department of Pathology, Cell Biology, Columbia University Medical Center, NY 10032, United States; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, NY 10032, United States; Department of Psychiatry, Columbia University Medical Center, NY 10032, United States
| | - H Moreno
- Department of Neurology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States; The Robert F. Furchgott Center for Neural and Behavioral Science, Department of Physiology/Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY 11203, United States.
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27
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Sosa LJ, Cáceres A, Dupraz S, Oksdath M, Quiroga S, Lorenzo A. The physiological role of the amyloid precursor protein as an adhesion molecule in the developing nervous system. J Neurochem 2017; 143:11-29. [PMID: 28677143 DOI: 10.1111/jnc.14122] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 06/28/2017] [Accepted: 06/29/2017] [Indexed: 12/12/2022]
Abstract
The amyloid precursor protein (APP) is a type I transmembrane glycoprotein better known for its participation in the physiopathology of Alzheimer disease as the source of the beta amyloid fragment. However, the physiological functions of the full length protein and its proteolytic fragments have remained elusive. APP was first described as a cell-surface receptor; nevertheless, increasing evidence highlighted APP as a cell adhesion molecule. In this review, we will focus on the current knowledge of the physiological role of APP as a cell adhesion molecule and its involvement in key events of neuronal development, such as migration, neurite outgrowth, growth cone pathfinding, and synaptogenesis. Finally, since APP is over-expressed in Down syndrome individuals because of the extra copy of chromosome 21, in the last section of the review, we discuss the potential contribution of APP to the neuronal and synaptic defects described in this genetic condition. Read the Editorial Highlight for this article on page 9. Cover Image for this issue: doi. 10.1111/jnc.13817.
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Affiliation(s)
- Lucas J Sosa
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Alfredo Cáceres
- Laboratorio Neurobiología, Instituto Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina.,Instituto Universitario Ciencias Biomédicas Córdoba, Córdoba, Argentina
| | - Sebastián Dupraz
- Axonal Growth and Regeneration, German Center for Neurodegenarative Diseases, Bonn, Germany
| | - Mariana Oksdath
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Santiago Quiroga
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Alfredo Lorenzo
- Laboratorio de Neuropatología Experimental, Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
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28
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Pitt J, Wilcox KC, Tortelli V, Diniz LP, Oliveira MS, Dobbins C, Yu XW, Nandamuri S, Gomes FCA, DiNunno N, Viola KL, De Felice FG, Ferreira ST, Klein WL. Neuroprotective astrocyte-derived insulin/insulin-like growth factor 1 stimulates endocytic processing and extracellular release of neuron-bound Aβ oligomers. Mol Biol Cell 2017; 28:2623-2636. [PMID: 28963439 PMCID: PMC5620371 DOI: 10.1091/mbc.e17-06-0416] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 07/31/2017] [Indexed: 12/19/2022] Open
Abstract
Synaptopathy underlying memory deficits in Alzheimer's disease (AD) is increasingly thought to be instigated by toxic oligomers of the amyloid beta peptide (AβOs). Given the long latency and incomplete penetrance of AD dementia with respect to Aβ pathology, we hypothesized that factors present in the CNS may physiologically protect neurons from the deleterious impact of AβOs. Here we employed physically separated neuron-astrocyte cocultures to investigate potential non-cell autonomous neuroprotective factors influencing AβO toxicity. Neurons cultivated in the absence of an astrocyte feeder layer showed abundant AβO binding to dendritic processes and associated synapse deterioration. In contrast, neurons in the presence of astrocytes showed markedly reduced AβO binding and synaptopathy. Results identified the protective factors released by astrocytes as insulin and insulin-like growth factor-1 (IGF1). The protective mechanism involved release of newly bound AβOs into the extracellular medium dependent upon trafficking that was sensitive to exosome pathway inhibitors. Delaying insulin treatment led to AβO binding that was no longer releasable. The neuroprotective potential of astrocytes was itself sensitive to chronic AβO exposure, which reduced insulin/IGF1 expression. Our findings support the idea that physiological protection against synaptotoxic AβOs can be mediated by astrocyte-derived insulin/IGF1, but that this protection itself is vulnerable to AβO buildup.
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Affiliation(s)
- Jason Pitt
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208.,Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Kyle C Wilcox
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
| | - Vanessa Tortelli
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil
| | - Luan Pereira Diniz
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil
| | - Maira S Oliveira
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil
| | - Cassandra Dobbins
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
| | - Xiao-Wen Yu
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Sathwik Nandamuri
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
| | - Flávia C A Gomes
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil
| | - Nadia DiNunno
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
| | - Kirsten L Viola
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
| | - Fernanda G De Felice
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil.,Centre for Neuroscience Studies, Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Sergio T Ferreira
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil.,Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil
| | - William L Klein
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
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29
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Puzzo D, Piacentini R, Fá M, Gulisano W, Li Puma DD, Staniszewski A, Zhang H, Tropea MR, Cocco S, Palmeri A, Fraser P, D'Adamio L, Grassi C, Arancio O. LTP and memory impairment caused by extracellular Aβ and Tau oligomers is APP-dependent. eLife 2017; 6. [PMID: 28696204 PMCID: PMC5529106 DOI: 10.7554/elife.26991] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 07/10/2017] [Indexed: 12/21/2022] Open
Abstract
The concurrent application of subtoxic doses of soluble oligomeric forms of human amyloid-beta (oAβ) and Tau (oTau) proteins impairs memory and its electrophysiological surrogate long-term potentiation (LTP), effects that may be mediated by intra-neuronal oligomers uptake. Intrigued by these findings, we investigated whether oAβ and oTau share a common mechanism when they impair memory and LTP in mice. We found that as already shown for oAβ, also oTau can bind to amyloid precursor protein (APP). Moreover, efficient intra-neuronal uptake of oAβ and oTau requires expression of APP. Finally, the toxic effect of both extracellular oAβ and oTau on memory and LTP is dependent upon APP since APP-KO mice were resistant to oAβ- and oTau-induced defects in spatial/associative memory and LTP. Thus, APP might serve as a common therapeutic target against Alzheimer's Disease (AD) and a host of other neurodegenerative diseases characterized by abnormal levels of Aβ and/or Tau. DOI:http://dx.doi.org/10.7554/eLife.26991.001
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Affiliation(s)
- Daniela Puzzo
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Roberto Piacentini
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Mauro Fá
- Department of Pathology and Cell Biology and Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, United States
| | - Walter Gulisano
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Domenica D Li Puma
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Agnes Staniszewski
- Department of Pathology and Cell Biology and Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, United States
| | - Hong Zhang
- Department of Pathology and Cell Biology and Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, United States
| | - Maria Rosaria Tropea
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Sara Cocco
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Agostino Palmeri
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Paul Fraser
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Luciano D'Adamio
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, New York, United States
| | - Claudio Grassi
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Ottavio Arancio
- Department of Pathology and Cell Biology and Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New york, United States
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30
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Wang H, Muiznieks LD, Ghosh P, Williams D, Solarski M, Fang A, Ruiz-Riquelme A, Pomès R, Watts JC, Chakrabartty A, Wille H, Sharpe S, Schmitt-Ulms G. Somatostatin binds to the human amyloid β peptide and favors the formation of distinct oligomers. eLife 2017. [PMID: 28650319 PMCID: PMC5505701 DOI: 10.7554/elife.28401] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The amyloid β peptide (Aβ) is a key player in the etiology of Alzheimer disease (AD), yet a systematic investigation of its molecular interactions has not been reported. Here we identified by quantitative mass spectrometry proteins in human brain extract that bind to oligomeric Aβ1-42 (oAβ1-42) and/or monomeric Aβ1-42 (mAβ1-42) baits. Remarkably, the cyclic neuroendocrine peptide somatostatin-14 (SST14) was observed to be the most selectively enriched oAβ1-42 binder. The binding interface comprises a central tryptophan within SST14 and the N-terminus of Aβ1-42. The presence of SST14 inhibited Aβ aggregation and masked the ability of several antibodies to detect Aβ. Notably, Aβ1-42, but not Aβ1-40, formed in the presence of SST14 oligomeric assemblies of 50 to 60 kDa that were visualized by gel electrophoresis, nanoparticle tracking analysis and electron microscopy. These findings may be relevant for Aβ-directed diagnostics and may signify a role of SST14 in the etiology of AD. DOI:http://dx.doi.org/10.7554/eLife.28401.001 Treating Alzheimer’s disease and related dementias is one of the major challenges currently facing healthcare providers worldwide. A hallmark of the disease is the formation of large deposits of a specific molecule, known as amyloid beta (Aβ), in the brain. However, more and more research suggests that smaller and particularly toxic amyloid beta clumps – often referred to as oligomeric Aβ – appear as an early sign of Alzheimer’s disease. To understand how the formation of these smaller amyloid beta clumps triggers other aspects of the disease, it is important to identify molecules in the human brain that oligomeric Aβ binds to. To this end, Wang et al. attached amyloid beta or oligomeric Aβ molecules to microscopically small beads. The beads were then exposed to human brain extracts in a test tube, which allowed molecules in the extracts to bind to the amyloid beta or oligomeric Aβ. The samples were then spun at high speed, meaning that the beads and any other molecules bound to them sunk and formed pellets at the bottom of the tubes. Each pellet was then analyzed to see which molecules it contained. The experiments identified more than a hundred human brain proteins that can bind to amyloid beta. One of them, known as somatostatin, selectively binds to oligomeric Aβ. Wang et al. were able to determine the structural features of somatostatin that control this binding. Finally, in further experiments performed in test tubes, Wang et al. noticed that smaller oligomeric Aβ clumps were more likely to form than larger amyloid beta deposits when somatostatin was present. This could signify a previously unrecognized role of somatostatin in the development of Alzheimer’s disease. Further studies are now needed to confirm whether the presence of somatostatin in the brain favors the formation of smaller, toxic oligomeric Aβ clumps over large innocuous amyloid beta deposits. If so, new treatments could be developed that aim to reduce oligomeric Aβ levels in the brain by preventing somatostatin from interacting with amyloid beta molecules. Wang et al. also suggest that somatostatin could be used in diagnostic tests to detect abnormal levels of oligomeric Aβ in the brain or body fluids of people who have Alzheimer’s disease. DOI:http://dx.doi.org/10.7554/eLife.28401.002
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Affiliation(s)
- Hansen Wang
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Canada
| | - Lisa D Muiznieks
- Molecular Medicine Program, Research Institute, The Hospital for Sick Children, Toronto, Canada
| | - Punam Ghosh
- Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Declan Williams
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Canada
| | - Michael Solarski
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Andrew Fang
- Department of Biochemistry, University of Alberta, Edmonton, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
| | - Alejandro Ruiz-Riquelme
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Canada
| | - Régis Pomès
- Molecular Medicine Program, Research Institute, The Hospital for Sick Children, Toronto, Canada.,Department of Biochemistry, University of Toronto, Toronto, Canada
| | - Joel C Watts
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Canada.,Department of Biochemistry, University of Toronto, Toronto, Canada
| | - Avi Chakrabartty
- Department of Medical Biophysics, University of Toronto, Toronto, Canada.,Department of Biochemistry, University of Toronto, Toronto, Canada
| | - Holger Wille
- Department of Biochemistry, University of Alberta, Edmonton, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
| | - Simon Sharpe
- Molecular Medicine Program, Research Institute, The Hospital for Sick Children, Toronto, Canada.,Department of Biochemistry, University of Toronto, Toronto, Canada
| | - Gerold Schmitt-Ulms
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
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31
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Kirouac L, Rajic AJ, Cribbs DH, Padmanabhan J. Activation of Ras-ERK Signaling and GSK-3 by Amyloid Precursor Protein and Amyloid Beta Facilitates Neurodegeneration in Alzheimer's Disease. eNeuro 2017; 4:ENEURO.0149-16.2017. [PMID: 28374012 PMCID: PMC5367084 DOI: 10.1523/eneuro.0149-16.2017] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 02/23/2017] [Accepted: 02/26/2017] [Indexed: 02/01/2023] Open
Abstract
It is widely accepted that amyloid β (Aβ) generated from amyloid precursor protein (APP) oligomerizes and fibrillizes to form neuritic plaques in Alzheimer's disease (AD), yet little is known about the contribution of APP to intracellular signaling events preceding AD pathogenesis. The data presented here demonstrate that APP expression and neuronal exposure to oligomeric Aβ42 enhance Ras/ERK signaling cascade and glycogen synthase kinase 3 (GSK-3) activation. We find that RNA interference (RNAi)-directed knockdown of APP in B103 rat neuroblastoma cells expressing APP inhibits Ras-ERK signaling and GSK-3 activation, indicating that APP acts upstream of these signal transduction events. Both ERK and GSK-3 are known to induce hyperphosphorylation of tau and APP at Thr668, and our findings suggest that aberrant signaling by APP facilitates these events. Supporting this notion, analysis of human AD brain samples showed increased expression of Ras, activation of GSK-3, and phosphorylation of APP and tau, which correlated with Aβ levels in the AD brains. Furthermore, treatment of primary rat neurons with Aβ recapitulated these events and showed enhanced Ras-ERK signaling, GSK-3 activation, upregulation of cyclin D1, and phosphorylation of APP and tau. The finding that Aβ induces Thr668 phosphorylation on APP, which enhances APP proteolysis and Aβ generation, denotes a vicious feedforward mechanism by which APP and Aβ promote tau hyperphosphorylation and neurodegeneration in AD. Based on these results, we hypothesize that aberrant proliferative signaling by APP plays a fundamental role in AD neurodegeneration and that inhibition of this would impede cell cycle deregulation and neurodegeneration observed in AD.
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Affiliation(s)
- Lisa Kirouac
- Department of Molecular Medicine, USF Health Byrd Alzheimer’s Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33613
| | - Alexander J. Rajic
- Institute for Memory Impairment and Neurological Disorders, Department of Neurology, University of California, Irvine, Irvine, CA 92697-4540
| | - David H. Cribbs
- Institute for Memory Impairment and Neurological Disorders, Department of Neurology, University of California, Irvine, Irvine, CA 92697-4540
| | - Jaya Padmanabhan
- Department of Molecular Medicine, USF Health Byrd Alzheimer’s Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33613
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32
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Poksay KS, Sheffler DJ, Spilman P, Campagna J, Jagodzinska B, Descamps O, Gorostiza O, Matalis A, Mullenix M, Bredesen DE, Cosford NDP, John V. Screening for Small Molecule Inhibitors of Statin-Induced APP C-terminal Toxic Fragment Production. Front Pharmacol 2017; 8:46. [PMID: 28261092 PMCID: PMC5309220 DOI: 10.3389/fphar.2017.00046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Accepted: 01/20/2017] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD) is characterized by neuronal and synaptic loss. One process that could contribute to this loss is the intracellular caspase cleavage of the amyloid precursor protein (APP) resulting in release of the toxic C-terminal 31-amino acid peptide APP-C31 along with the production of APPΔC31, full-length APP minus the C-terminal 31 amino acids. We previously found that a mutation in APP that prevents this caspase cleavage ameliorated synaptic loss and cognitive impairment in a murine AD model. Thus, inhibition of this cleavage is a reasonable target for new therapeutic development. In order to identify small molecules that inhibit the generation of APP-C31, we first used an APPΔC31 cleavage site-specific antibody to develop an AlphaLISA to screen several chemical compound libraries for the level of N-terminal fragment production. This antibody was also used to develop an ELISA for validation studies. In both high throughput screening (HTS) and validation testing, the ability of compounds to inhibit simvastatin- (HTS) or cerivastatin- (validation studies) induced caspase cleavage at the APP-D720 cleavage site was determined in Chinese hamster ovary (CHO) cells stably transfected with wildtype (wt) human APP (CHO-7W). Several compounds, as well as control pan-caspase inhibitor Q-VD-OPh, inhibited APPΔC31 production (measured fragment) and rescued cell death in a dose-dependent manner. The effective compounds fell into several classes including SERCA inhibitors, inhibitors of Wnt signaling, and calcium channel antagonists. Further studies are underway to evaluate the efficacy of lead compounds - identified here using cells and tissues expressing wt human APP - in mouse models of AD expressing mutated human APP, as well as to identify additional compounds and determine the mechanisms by which they exert their effects.
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Affiliation(s)
- Karen S Poksay
- Bredesen Lab, Buck Institute for Research on Aging, Novato CA, USA
| | - Douglas J Sheffler
- Cancer Metabolism and Signaling Networks Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla CA, USA
| | - Patricia Spilman
- Bredesen Lab, Buck Institute for Research on Aging, NovatoCA, USA; Drug Discovery Lab, Department of Neurology, University of California, Los AngelesCA, USA
| | - Jesus Campagna
- Drug Discovery Lab, Department of Neurology, University of California, Los Angeles CA, USA
| | - Barbara Jagodzinska
- Drug Discovery Lab, Department of Neurology, University of California, Los Angeles CA, USA
| | - Olivier Descamps
- Bredesen Lab, Buck Institute for Research on Aging, Novato CA, USA
| | - Olivia Gorostiza
- Bredesen Lab, Buck Institute for Research on Aging, Novato CA, USA
| | - Alex Matalis
- Bredesen Lab, Buck Institute for Research on Aging, Novato CA, USA
| | | | - Dale E Bredesen
- Bredesen Lab, Buck Institute for Research on Aging, NovatoCA, USA; Drug Discovery Lab, Department of Neurology, University of California, Los AngelesCA, USA
| | - Nicholas D P Cosford
- Cancer Metabolism and Signaling Networks Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla CA, USA
| | - Varghese John
- Drug Discovery Lab, Department of Neurology, University of California, Los Angeles CA, USA
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33
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Canu N, Pagano I, La Rosa LR, Pellegrino M, Ciotti MT, Mercanti D, Moretti F, Sposato V, Triaca V, Petrella C, Maruyama IN, Levi A, Calissano P. Association of TrkA and APP Is Promoted by NGF and Reduced by Cell Death-Promoting Agents. Front Mol Neurosci 2017; 10:15. [PMID: 28197073 PMCID: PMC5281621 DOI: 10.3389/fnmol.2017.00015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 01/11/2017] [Indexed: 12/31/2022] Open
Abstract
The amyloid precursor protein (APP) interacts with the tropomyosin receptor kinase A (TrkA) in normal rat, mouse, and human brain tissue but not in Alzheimer's disease (AD) brain tissue. However, it has not been reported whether the two proteins interact directly, and if so, which domains are involved. Clarifying these points will increase our understanding of the role and regulation of the TrkA/APP interaction in normal brain functioning as well as in AD. Here we addressed these questions using bimolecular fluorescence complementation (BiFC) and the proximity ligation assay (PLA). We demonstrated that exogenously expressed APP and TrkA associate through their juxtamembrane/transmembrane domains, to form a complex that localizes mainly to the plasma membrane, endoplasmic reticulum (ER) and Golgi. Formation of the complex was inhibited by p75NTR, ShcC and Mint-2. Importantly, we demonstrated that the association between endogenous APP and TrkA in primary septal neurons were modified by NGF, or by drugs that either inhibit ER-to-Golgi transport or perturb microtubules and microfilaments. Interestingly, several agents that induce cell death [amyloid β (Aβ)-peptide, staurosporine and rapamycin], albeit via different mechanisms, all caused dissociation of APP/TrkA complexes and increased production of C-terminal fragment (β-CTF) APP fragment. These findings open new perspectives for investigating the interplay between these proteins during neurodegeneration and AD.
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Affiliation(s)
- Nadia Canu
- Department of System Medicine, University of Rome "Tor Vergata"Rome, Italy; Institute of Cellular Biology and Neurobiology, National Council of Research of RomeRome, Italy
| | - Ilaria Pagano
- Institute of Cellular Biology and Neurobiology, National Council of Research of Rome Rome, Italy
| | - Luca Rosario La Rosa
- Institute of Cellular Biology and Neurobiology, National Council of Research of Rome Rome, Italy
| | - Marsha Pellegrino
- Institute of Cellular Biology and Neurobiology, National Council of Research of Rome Rome, Italy
| | - Maria Teresa Ciotti
- Institute of Cellular Biology and Neurobiology, National Council of Research of Rome Rome, Italy
| | - Delio Mercanti
- Institute of Cellular Biology and Neurobiology, National Council of Research of Rome Rome, Italy
| | - Fabiola Moretti
- Institute of Cellular Biology and Neurobiology, National Council of Research of Rome Rome, Italy
| | - Valentina Sposato
- Institute of Cellular Biology and Neurobiology, National Council of Research of RomeRome, Italy; European Brain Research InstituteRome, Italy
| | - Viviana Triaca
- Institute of Cellular Biology and Neurobiology, National Council of Research of RomeRome, Italy; European Brain Research InstituteRome, Italy
| | - Carla Petrella
- Institute of Cellular Biology and Neurobiology, National Council of Research of Rome Rome, Italy
| | - Ichiro N Maruyama
- Information Processing Biology Unit, Okinawa Institute of Science and Technology Graduate University Okinawa, Japan
| | - Andrea Levi
- Institute of Cellular Biology and Neurobiology, National Council of Research of Rome Rome, Italy
| | - Pietro Calissano
- European Brain Research InstituteRome, Italy; Institute of Cellular Biology and Neurobiology, National Council of Research of RomeRome, Italy
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34
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Spilman PR, Corset V, Gorostiza O, Poksay KS, Galvan V, Zhang J, Rao R, Peters-Libeu C, Vincelette J, McGeehan A, Dvorak-Ewell M, Beyer J, Campagna J, Bankiewicz K, Mehlen P, John V, Bredesen DE. Netrin-1 Interrupts Amyloid-β Amplification, Increases sAβPPα in vitro and in vivo, and Improves Cognition in a Mouse Model of Alzheimer's Disease. J Alzheimers Dis 2017; 52:223-42. [PMID: 27060954 DOI: 10.3233/jad-151046] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Recent studies have shown that inoculation of susceptible mice with amyloid-β (Aβ) peptides accelerates Aβ deposition in the brain, supporting the idea that Aβ may be self-amplifying; however, the exact mechanism is not understood. Here we provide evidence that Aβ may self-amplify, in part, by inhibiting α-secretase ADAM10 (a disintegrin and metalloprotease) cleavage of full-length Aβ precursor protein (FL AβPP) and therefore allow greater β-secretase processing, and that Aβ itself is a substrate for ADAM10. Exposure of primary neuronal cultures from PDAβPP mice to exogenous rat Aβ1- 40 resulted in increased de novo human Aβ1-42 production and exposure of cells to Aβ decreased production of ADAM10 cleavage product soluble AβPPα (sAβPPα). In a cell-free assay, Aβ decreased ADAM10 cleavage of the chimeric substrate MBP-AβPPC125 and Aβ itself was apparently cleaved by the enzyme. The axonal guidance and trophic factor netrin-1, however, reduced the Aβ1- 40-induced Aβ1-42 increase, increased sAβPPα, and reversed the Aβ-induced sAβPPα decrease in vitro. In vivo, induction of netrin-1 expression in PDAβPPSwe/Ind transgenic mice resulted in reductions in both Aβ1-42 and Aβ1- 40, and ICV delivery of netrin-1 to PDAβPPSwe/Ind mice increased sAβPPα, decreased Aβ, and improved working memory. Finally, to support further study of netrin-1's potential as a therapeutic for Alzheimer's disease, pilot gene therapy studies were performed and a netrin mimetic peptide synthesized and tested that, like netrin, can increase sAβPPα and decrease Aβ1-42in vitro. Taken together, these data provide mechanistic insights into Aβ self-amplification and the ability of netrin-1 to disrupt it.
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Affiliation(s)
- Patricia R Spilman
- Buck Institute for Research on Aging, Novato, CA, USA.,Drug Discovery Laboratory, Department of Neurology & Easton Center for AD Research, University of California, Los Angeles, CA, USA
| | - Veronique Corset
- Buck Institute for Research on Aging, Novato, CA, USA.,Apoptosis, Cancer and Development Laboratory, University of Lyon Cancer Center, Centre Léon Bérard, Lyon, France
| | | | | | | | - Junli Zhang
- Buck Institute for Research on Aging, Novato, CA, USA
| | - Rammohan Rao
- Buck Institute for Research on Aging, Novato, CA, USA
| | | | | | | | | | - Janine Beyer
- Laboratory for Translational Neuroscience Research, Department of Neurological Surgery, University of California, San Francisco, CA, USA
| | - Jesus Campagna
- Buck Institute for Research on Aging, Novato, CA, USA.,Drug Discovery Laboratory, Department of Neurology & Easton Center for AD Research, University of California, Los Angeles, CA, USA
| | - Krystof Bankiewicz
- Laboratory for Translational Neuroscience Research, Department of Neurological Surgery, University of California, San Francisco, CA, USA
| | - Patrick Mehlen
- Apoptosis, Cancer and Development Laboratory, University of Lyon Cancer Center, Centre Léon Bérard, Lyon, France
| | - Varghese John
- Buck Institute for Research on Aging, Novato, CA, USA.,Drug Discovery Laboratory, Department of Neurology & Easton Center for AD Research, University of California, Los Angeles, CA, USA
| | - Dale E Bredesen
- Buck Institute for Research on Aging, Novato, CA, USA.,Drug Discovery Laboratory, Department of Neurology & Easton Center for AD Research, University of California, Los Angeles, CA, USA
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35
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Preat T, Goguel V. Role of Drosophila Amyloid Precursor Protein in Memory Formation. Front Mol Neurosci 2016; 9:142. [PMID: 28008309 PMCID: PMC5143682 DOI: 10.3389/fnmol.2016.00142] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 11/28/2016] [Indexed: 12/22/2022] Open
Abstract
The amyloid precursor protein (APP) is a membrane protein engaged in complex proteolytic pathways. APP and its derivatives have been shown to play a central role in Alzheimer’s disease (AD), a progressive neurodegenerative disease characterized by memory decline. Despite a huge effort from the research community, the primary cause of AD remains unclear, making it crucial to better understand the physiological role of the APP pathway in brain plasticity and memory. Drosophila melanogaster is a model system well-suited to address this issue. Although relatively simple, the fly brain is highly organized, sustains several forms of learning and memory, and drives numerous complex behaviors. Importantly, molecules and mechanisms underlying memory processes are conserved from flies to mammals. The fly encodes a single non-essential APP homolog named APP-Like (APPL). Using in vivo inducible RNA interference strategies, it was shown that APPL knockdown in the mushroom bodies (MB)—the central integrative brain structure for olfactory memory—results in loss of memory. Several APPL derivatives, such as secreted and full-length membrane APPL, may play different roles in distinct types of memory phases. Furthermore, overexpression of Drosophila amyloid peptide exacerbates the memory deficit caused by APPL knockdown, thus potentiating memory decline. Data obtained in the fly support the hypothesis that APP acts as a transmembrane receptor, and that disruption of its normal function may contribute to cognitive impairment during early AD.
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Affiliation(s)
- Thomas Preat
- Genes and Dynamics of Memory Systems, Brain Plasticity Unit, Centre National de la Recherche Scientifique (CNRS), ESPCI Paris, PSL Research University Paris, France
| | - Valérie Goguel
- Genes and Dynamics of Memory Systems, Brain Plasticity Unit, Centre National de la Recherche Scientifique (CNRS), ESPCI Paris, PSL Research University Paris, France
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36
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Evangelisti E, Cascella R, Becatti M, Marrazza G, Dobson CM, Chiti F, Stefani M, Cecchi C. Binding affinity of amyloid oligomers to cellular membranes is a generic indicator of cellular dysfunction in protein misfolding diseases. Sci Rep 2016; 6:32721. [PMID: 27619987 PMCID: PMC5020652 DOI: 10.1038/srep32721] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 08/10/2016] [Indexed: 11/10/2022] Open
Abstract
The conversion of peptides or proteins from their soluble native states into intractable amyloid deposits is associated with a wide range of human disorders. Misfolded protein oligomers formed during the process of aggregation have been identified as the primary pathogenic agents in many such conditions. Here, we show the existence of a quantitative relationship between the degree of binding to neuronal cells of different types of oligomers formed from a model protein, HypF-N, and the GM1 content of the plasma membranes. In addition, remarkably similar behavior is observed for oligomers of the Aβ42 peptide associated with Alzheimer’s disease. Further analysis has revealed the existence of a linear correlation between the level of the influx of Ca2+ across neuronal membranes that triggers cellular damage, and the fraction of oligomeric species bound to the membrane. Our findings indicate that the susceptibility of neuronal cells to different types of misfolded oligomeric assemblies is directly related to the extent of binding of such oligomers to the cellular membrane.
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Affiliation(s)
- Elisa Evangelisti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio" and Research Centre on the Molecular Basis of Neurodegeneration (CIMN), University of Florence, Viale Morgagni 50, 50134 Florence, Italy
| | - Roberta Cascella
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio" and Research Centre on the Molecular Basis of Neurodegeneration (CIMN), University of Florence, Viale Morgagni 50, 50134 Florence, Italy
| | - Matteo Becatti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio" and Research Centre on the Molecular Basis of Neurodegeneration (CIMN), University of Florence, Viale Morgagni 50, 50134 Florence, Italy
| | - Giovanna Marrazza
- Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Florence, Italy
| | - Christopher M Dobson
- Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW Cambridge, UK
| | - Fabrizio Chiti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio" and Research Centre on the Molecular Basis of Neurodegeneration (CIMN), University of Florence, Viale Morgagni 50, 50134 Florence, Italy
| | - Massimo Stefani
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio" and Research Centre on the Molecular Basis of Neurodegeneration (CIMN), University of Florence, Viale Morgagni 50, 50134 Florence, Italy
| | - Cristina Cecchi
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio" and Research Centre on the Molecular Basis of Neurodegeneration (CIMN), University of Florence, Viale Morgagni 50, 50134 Florence, Italy
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37
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Yamin G, Coppola G, Teplow DB. Design, Characterization, and Use of a Novel Amyloid β-Protein Control for Assembly, Neurotoxicity, and Gene Expression Studies. Biochemistry 2016; 55:5049-60. [PMID: 27505174 DOI: 10.1021/acs.biochem.6b00579] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A key pathogenic agent in Alzheimer's disease (AD) is the amyloid β-protein (Aβ), which self-assembles into a variety of neurotoxic structures. Establishing structure-activity relationships for these assemblies, which is critical for proper therapeutic target identification and design, requires aggregation and neurotoxicity experiments that are properly controlled with respect to the Aβ peptide itself. "Reverse" Aβ or non-Aβ peptides suffer from the fact that their biophysical properties are too similar or dissimilar, respectively, to those of native Aβ for them to be appropriate controls. For this reason, we used simple protein design principles to create scrambled Aβ peptides predicted to behave distinctly from native Aβ. We showed that our prediction was true by monitoring secondary structure dynamics with thioflavin T fluorescence and circular dichroism spectroscopy, determining oligomer size distributions, and assaying neurotoxic activity. We then demonstrated the utility of the scrambled Aβ peptides by using them to control experiments examining the effects of Aβ monomers, dimers, higher-order oligomers, and fibrils on gene expression in primary rat hippocampal neurons. Significant changes in gene expression were observed for all peptide assemblies, but fibrils induced the largest changes. Weighted gene co-expression network analysis revealed two predominant gene modules related to Aβ treatment. Many genes within these modules were associated with inflammatory signaling pathways.
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Affiliation(s)
- Ghiam Yamin
- Department of Radiology, University of California San Diego School of Medicine , La Jolla, California 92093, United States.,Department of Neurology, David Geffen School of Medicine at UCLA , Los Angeles, California 90095, United States
| | - Giovanni Coppola
- Department of Neurology, David Geffen School of Medicine at UCLA , Los Angeles, California 90095, United States.,Department of Psychiatry and Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at UCLA , Los Angeles, California 90095, United States
| | - David B Teplow
- Department of Neurology, David Geffen School of Medicine at UCLA , Los Angeles, California 90095, United States
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38
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Trillaud-Doppia E, Paradis-Isler N, Boehm J. A single amino acid difference between the intracellular domains of amyloid precursor protein and amyloid-like precursor protein 2 enables induction of synaptic depression and block of long-term potentiation. Neurobiol Dis 2016; 91:94-104. [PMID: 26921470 DOI: 10.1016/j.nbd.2016.02.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Revised: 01/29/2016] [Accepted: 02/23/2016] [Indexed: 12/16/2022] Open
Abstract
Alzheimer disease (AD) is initially characterized as a disease of the synapse that affects synaptic transmission and synaptic plasticity. While amyloid-beta and tau have been traditionally implicated in causing AD, recent studies suggest that other factors, such as the intracellular domain of the amyloid-precursor protein (APP-ICD), can also play a role in the development of AD. Here, we show that the expression of APP-ICD induces synaptic depression, while the intracellular domain of its homolog amyloid-like precursor protein 2 (APLP2-ICD) does not. We are able to show that this effect by APP-ICD is due to a single alanine vs. proline difference between APP-ICD and APLP2-ICD. The alanine in APP-ICD and the proline in APLP2-ICD lie directly behind a conserved caspase cleavage site. Inhibition of caspase cleavage of APP-ICD prevents the induction of synaptic depression. Finally, we show that the expression of APP-ICD increases and facilitates long-term depression and blocks induction of long-term potentiation. The block in long-term potentiation can be overcome by mutating the aforementioned alanine in APP-ICD to the proline of APLP2. Based on our results, we propose the emergence of a new APP critical domain for the regulation of synaptic plasticity and in consequence for the development of AD.
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Affiliation(s)
- Emilie Trillaud-Doppia
- Département Neurosciences, Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec H3T 1J4, Canada
| | - Nicolas Paradis-Isler
- Département Neurosciences, Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec H3T 1J4, Canada
| | - Jannic Boehm
- Département Neurosciences, Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec H3T 1J4, Canada.
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39
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Decock M, El Haylani L, Stanga S, Dewachter I, Octave JN, Smith SO, Constantinescu SN, Kienlen-Campard P. Analysis by a highly sensitive split luciferase assay of the regions involved in APP dimerization and its impact on processing. FEBS Open Bio 2015; 5:763-73. [PMID: 26500837 PMCID: PMC4588712 DOI: 10.1016/j.fob.2015.09.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 08/07/2015] [Accepted: 09/01/2015] [Indexed: 12/27/2022] Open
Abstract
Amyloid precursor protein (APP) dimerizes more than its C-terminal fragments in cells. Mutations of membrane GXXXG motifs affect Aβ production but not APP dimerization. Deletion of the APP intracellular domain increases APP dimerization.
Alzheimer’s disease (AD) is a neurodegenerative disease that causes progressive loss of cognitive functions, leading to dementia. Two types of lesions are found in AD brains: neurofibrillary tangles and senile plaques. The latter are composed mainly of the β-amyloid peptide (Aβ) generated by amyloidogenic processing of the amyloid precursor protein (APP). Several studies have suggested that dimerization of APP is closely linked to Aβ production. Nevertheless, the mechanisms controlling APP dimerization and their role in APP function are not known. Here we used a new luciferase complementation assay to analyze APP dimerization and unravel the involvement of its three major domains: the ectodomain, the transmembrane domain and the intracellular domain. Our results indicate that within cells full-length APP dimerizes more than its α and β C-terminal fragments, confirming the pivotal role of the ectodomain in this process. Dimerization of the APP transmembrane (TM) domain has been reported to regulate processing at the γ-cleavage site. We show that both non-familial and familial AD mutations in the TM GXXXG motifs strongly modulate Aβ production, but do not consistently change dimerization of the C-terminal fragments. Finally, we found for the first time that removal of intracellular domain strongly increases APP dimerization. Increased APP dimerization is linked to increased non-amyloidogenic processing.
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Key Words
- AD, Alzheimer’s disease
- AICD, APP intracellular domain
- APP
- APP, amyloid precursor protein
- Alzheimer disease
- Amyloid beta peptide
- Aβ, β-amyloid peptide
- CHO, chinese hamster ovary
- CTF, C-terminal fragment
- DAPT, N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester
- DTT, dithiothreitol
- Dimerization
- ECL, enzymatic chemi-luminescence
- ECLIA, electro-chemiluminescence immuno-assay
- FBS, fetal bovine serum
- FRET, fluorescence resonance energy transfer
- GXXXG motifs
- KPI, Kunitz-type protease inhibitor
- NSAIDs, nonsteroidal anti-inflammatory drugs
- PBS, phosphate buffered saline
- PS1/PS2, presenilin1/presenilin2
- RLU, relative light unit
- SP, signal peptide
- Split luciferase
- TM, transmembrane
- YFP, yellow fluorescent protein
- sAPPα, soluble APPα
- sAPPβ, soluble APPβ
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Affiliation(s)
- Marie Decock
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Laetitia El Haylani
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Serena Stanga
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Ilse Dewachter
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Jean-Noël Octave
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Steven O Smith
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
| | - Stefan N Constantinescu
- de Duve Institute and Ludwig Institute for Cancer Research, Université catholique de Louvain, Brussels 1200, Belgium
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40
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Bourdet I, Lampin-Saint-Amaux A, Preat T, Goguel V. Amyloid-β Peptide Exacerbates the Memory Deficit Caused by Amyloid Precursor Protein Loss-of-Function in Drosophila. PLoS One 2015; 10:e0135741. [PMID: 26274614 PMCID: PMC4537105 DOI: 10.1371/journal.pone.0135741] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 07/26/2015] [Indexed: 11/18/2022] Open
Abstract
The amyloid precursor protein (APP) plays a central role in Alzheimer's disease (AD). APP can undergo two exclusive proteolytic pathways: cleavage by the α-secretase initiates the non-amyloidogenic pathway while cleavage by the β-secretase initiates the amyloidogenic pathway that leads, after a second cleavage by the γ-secretase, to amyloid-β (Aβ) peptides that can form toxic extracellular deposits, a hallmark of AD. The initial events leading to AD are still unknown. Importantly, aside from Aβ toxicity whose molecular mechanisms remain elusive, several studies have shown that APP plays a positive role in memory, raising the possibility that APP loss-of-function may participate to AD. We previously showed that APPL, the Drosophila APP ortholog, is required for associative memory in young flies. In the present report, we provide the first analysis of the amyloidogenic pathway's influence on memory in the adult. We show that transient overexpression of the β-secretase in the mushroom bodies, the center for olfactory memory, did not alter memory. In sharp contrast, β-secretase overexpression affected memory when associated with APPL partial loss-of-function. Interestingly, similar results were observed with Drosophila Aβ peptide. Because Aβ overexpression impaired memory only when combined to APPL partial loss-of-function, the data suggest that Aβ affects memory through the APPL pathway. Thus, memory is altered by two connected mechanisms-APPL loss-of-function and amyloid peptide toxicity-revealing in Drosophila a functional interaction between APPL and amyloid peptide.
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Affiliation(s)
- Isabelle Bourdet
- Genes and Dynamics of Memory Systems, Brain Plasticity Unit, CNRS, ESPCI-ParisTech, PSL Research University, 10 rue Vauquelin, 75005 Paris, France
| | - Aurélie Lampin-Saint-Amaux
- Genes and Dynamics of Memory Systems, Brain Plasticity Unit, CNRS, ESPCI-ParisTech, PSL Research University, 10 rue Vauquelin, 75005 Paris, France
| | - Thomas Preat
- Genes and Dynamics of Memory Systems, Brain Plasticity Unit, CNRS, ESPCI-ParisTech, PSL Research University, 10 rue Vauquelin, 75005 Paris, France
- * E-mail: (VG); (TP)
| | - Valérie Goguel
- Genes and Dynamics of Memory Systems, Brain Plasticity Unit, CNRS, ESPCI-ParisTech, PSL Research University, 10 rue Vauquelin, 75005 Paris, France
- * E-mail: (VG); (TP)
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41
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Abstract
Many lines of evidence support that β-amyloid (Aβ) peptides play an important role in Alzheimer's disease (AD), the most common cause of dementia. But despite much effort the molecular mechanisms of how Aβ contributes to AD remain unclear. While Aβ is generated from its precursor protein throughout life, the peptide is best known as the main component of amyloid plaques, the neuropathological hallmark of AD. Reduction in Aβ has been the major target of recent experimental therapies against AD. Unfortunately, human clinical trials targeting Aβ have not shown the hoped-for benefits. Thus, doubts have been growing about the role of Aβ as a therapeutic target. Here we review evidence supporting the involvement of Aβ in AD, highlight the importance of differentiating between various forms of Aβ, and suggest that a better understanding of Aβ's precise pathophysiological role in the disease is important for correctly targeting it for potential future therapy.
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Affiliation(s)
- Gunnar K. Gouras
- />Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Tomas T. Olsson
- />Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Oskar Hansson
- />Clinical Memory Research Unit, Clinical Sciences Malmö, Lund University, Lund, Sweden
- />Memory Clinic, Skåne University Hospital, Skåne, Sweden
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42
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Zhang Q, Descamps O, Hart MJ, Poksay KS, Spilman P, Kane DJ, Gorostiza O, John V, Bredesen DE. Paradoxical effect of TrkA inhibition in Alzheimer's disease models. J Alzheimers Dis 2014; 40:605-617. [PMID: 24531152 DOI: 10.3233/jad-130017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
An unbiased screen for compounds that block amyloid-β protein precursor (AβPP) caspase cleavage identified ADDN-1351, which reduced AβPP-C31 by 90%. Target identification studies showed that ADDN-1351 is a TrkA inhibitor, and, in complementary studies, TrkA overexpression increased AβPP-C31 and cell death. TrkA was shown to interact with AβPP and suppress AβPP-mediated transcriptional activation. Moreover, treatment of PDAPP transgenic mice with the known TrkA inhibitor GW441756 increased sAβPPα and the sAβPPα to Aβ ratio. These results suggest TrkA inhibition-rather than NGF activation-as a novel therapeutic approach, and raise the possibility that such an approach may counteract the hyperactive signaling resulting from the accumulation of active NGF-TrkA complexes due to reduced retrograde transport. The results also suggest that one component of an optimal therapy for Alzheimer's disease may be a TrkA inhibitor.
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Affiliation(s)
- Qiang Zhang
- Buck Institute for Research on Aging, Novato, CA, USA
| | | | | | | | | | - Darci J Kane
- Buck Institute for Research on Aging, Novato, CA, USA
| | | | - Varghese John
- Buck Institute for Research on Aging, Novato, CA, USA
| | - Dale E Bredesen
- Buck Institute for Research on Aging, Novato, CA, USA.,Department of Neurology, University of California, San Francisco, CA, USA
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43
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Intracellular accumulation of amyloid-β (Aβ) protein plays a major role in Aβ-induced alterations of glutamatergic synaptic transmission and plasticity. J Neurosci 2014; 34:12893-903. [PMID: 25232124 DOI: 10.1523/jneurosci.1201-14.2014] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Intracellular accumulation of amyloid-β (Aβ) protein has been proposed as an early event in AD pathogenesis. In patients with mild cognitive impairment, intraneuronal Aβ immunoreactivity was found especially in brain regions critically involved in the cognitive deficits of AD. Although a large body of evidence demonstrates that Aβ42 accumulates intraneuronally ((in)Aβ), the action and the role of Aβ42 buildup on synaptic function have been poorly investigated. Here, we demonstrate that basal synaptic transmission and LTP were markedly depressed following Aβ42 injection into the neuron through the patch pipette. Control experiments performed with the reverse peptide (Aβ42-1) allowed us to exclude that the effects of (in)Aβ depended on changes in oncotic pressure. To further investigate (in)Aβ synaptotoxicity we used an Aβ variant harboring oxidized methionine in position 35 that does not cross the neuronal plasma membrane and is not uploaded from the extracellular space. This Aβ42 variant had no effects on synaptic transmission and plasticity when applied extracellularly, but induced synaptic depression and LTP inhibition after patch-pipette dialysis. Finally, the injection of an antibody raised against human Aβ42 (6E10) in CA1 pyramidal neurons of mouse hippocampal brain slices and autaptic microcultures did not, per se, significantly affect LTP and basal synaptic transmission, but it protected against the toxic effects of extracellular Aβ42. Collectively, these findings suggest that Aβ42-induced impairment of glutamatergic synaptic function depends on its internalization and intracellular accumulation thus paving the way to a systemic proteomic analysis of intracellular targets/partners of Aβ42.
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44
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Fogel H, Frere S, Segev O, Bharill S, Shapira I, Gazit N, O'Malley T, Slomowitz E, Berdichevsky Y, Walsh DM, Isacoff EY, Hirsch JA, Slutsky I. APP homodimers transduce an amyloid-β-mediated increase in release probability at excitatory synapses. Cell Rep 2014; 7:1560-1576. [PMID: 24835997 DOI: 10.1016/j.celrep.2014.04.024] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 03/12/2014] [Accepted: 04/12/2014] [Indexed: 10/25/2022] Open
Abstract
Accumulation of amyloid-β peptides (Aβ), the proteolytic products of the amyloid precursor protein (APP), induces a variety of synaptic dysfunctions ranging from hyperactivity to depression that are thought to cause cognitive decline in Alzheimer's disease. While depression of synaptic transmission has been extensively studied, the mechanisms underlying synaptic hyperactivity remain unknown. Here, we show that Aβ40 monomers and dimers augment release probability through local fine-tuning of APP-APP interactions at excitatory hippocampal boutons. Aβ40 binds to the APP, increases the APP homodimer fraction at the plasma membrane, and promotes APP-APP interactions. The APP activation induces structural rearrangements in the APP/Gi/o-protein complex, boosting presynaptic calcium flux and vesicle release. The APP growth-factor-like domain (GFLD) mediates APP-APP conformational changes and presynaptic enhancement. Thus, the APP homodimer constitutes a presynaptic receptor that transduces signal from Aβ40 to glutamate release. Excessive APP activation may initiate a positive feedback loop, contributing to hippocampal hyperactivity in Alzheimer's disease.
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Affiliation(s)
- Hilla Fogel
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Samuel Frere
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Oshik Segev
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Shashank Bharill
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA 94720, USA
| | - Ilana Shapira
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Neta Gazit
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel; Sagol School of Neuroscience, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Tiernan O'Malley
- Laboratory for Neurodegenerative Research, School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Dublin 4, Republic of Ireland; Laboratory for Neurodegenerative Research, Center for Neurologic Diseases, Brigham & Women's Hospital, Harvard Institutes of Medicine, Boston, MA 02115, USA
| | - Edden Slomowitz
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Yevgeny Berdichevsky
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Center for Neurologic Diseases, Brigham & Women's Hospital, Harvard Institutes of Medicine, Boston, MA 02115, USA
| | - Ehud Y Isacoff
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA 94720, USA
| | - Joel A Hirsch
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Inna Slutsky
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel; Sagol School of Neuroscience, Tel Aviv University, 69978 Tel Aviv, Israel.
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45
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Caspase-2 is required for dendritic spine and behavioural alterations in J20 APP transgenic mice. Nat Commun 2013; 4:1939. [PMID: 23748737 PMCID: PMC4398315 DOI: 10.1038/ncomms2927] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 04/24/2013] [Indexed: 11/09/2022] Open
Abstract
Caspases have critical roles in Alzheimer's disease pathogenesis. Here we show that caspase-2 is required for the cognitive decline seen in human amyloid precursor protein transgenic mice (J20). The age-related changes in behaviour and dendritic spine density observed in these mice are absent when they lack caspase-2, in spite of similar levels of amyloid beta (Aβ) deposition and inflammation. A similar degree of protection is observed in cultured hippocampal neurons lacking caspase-2, which are immune to the synaptotoxic effects of Aβ. Our studies suggest that caspase-2 is a critical mediator in the activation of the RhoA/ROCK-II signalling pathway, leading to the collapse of dendritic spines. We propose that this is controlled by an inactive caspase-2/RhoA/ROCK-II complex localized in dendrites, which dissociates in the presence of Aβ, allowing for their activation and entry in the spine. These findings directly implicate caspase-2 as key driver of synaptic dysfunction in Alzheimer's disease and offer novel therapeutic targets.
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46
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Wild-type neural progenitors divide and differentiate normally in an amyloid-rich environment. J Neurosci 2013; 33:17335-41. [PMID: 24174666 DOI: 10.1523/jneurosci.1917-13.2013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Adult neurogenesis is modulated by a balance of extrinsic signals and intrinsic responses that maintain production of new granule cells in the hippocampus. Disorders that disrupt the proliferative niche can impair this process, and alterations in adult neurogenesis have been described in human autopsy tissue and transgenic mouse models of Alzheimer's disease. Because exogenous application of aggregated Aβ peptide is neurotoxic in vitro and extracellular Aβ deposits are the main pathological feature recapitulated by mouse models, cell-extrinsic effects of Aβ accumulation were thought to underlie the breakdown of hippocampal neurogenesis observed in Alzheimer's models. We tested this hypothesis using a bigenic mouse in which transgenic expression of APP was restricted to mature projection neurons. These mice allowed us to examine how wild-type neural progenitor cells responded to high levels of Aβ released from neighboring granule neurons. We find that the proliferation, determination, and survival of hippocampal adult-born granule neurons are unaffected in the APP bigenic mice, despite abundant amyloid pathology and robust neuroinflammation. Our findings suggest that Aβ accumulation is insufficient to impair adult hippocampal neurogenesis, and that factors other than amyloid pathology may account for the neurogenic deficits observed in transgenic models with more widespread APP expression.
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47
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Facchinetti P, Dorard E, Contremoulins V, Gaillard MC, Déglon N, Sazdovitch V, Guihenneuc-Jouyaux C, Brouillet E, Duyckaerts C, Allinquant B. SET translocation is associated with increase in caspase cleaved amyloid precursor protein in CA1 of Alzheimer and Down syndrome patients. Neurobiol Aging 2013; 35:958-68. [PMID: 24262202 DOI: 10.1016/j.neurobiolaging.2013.08.039] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 08/26/2013] [Accepted: 08/31/2013] [Indexed: 11/30/2022]
Abstract
Caspase cleaved amyloid precursor protein (APPcc) and SET are increased and mislocalized in the neuronal cytoplasm in Alzheimer Disease (AD) brains. Translocated SET to the cytoplasm can induce tau hyperphosphorylation. To elucidate the putative relationships between mislocalized APPcc and SET, we studied their level and distribution in the hippocampus of 5 controls, 3 Down syndrome and 10 Alzheimer patients. In Down syndrome and Alzheimer patients, APPcc and SET levels were increased in CA1 and the frequency of both localizations in the neuronal cytoplasm was high in CA1, and low in CA4. As the increase of APPcc is already present at early stages of AD, we overexpressed APPcc in CA1 and the dentate gyrus neurons of adult mice with a lentiviral construct. APPcc overexpression in CA1 and not in the dentate gyrus induced endogenous SET translocation and tau hyperphosphorylation. These data suggest that increase in APPcc in CA1 neurons could be an early event leading to the translocation of SET and the progression of AD through tau hyperphosphorylation.
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Affiliation(s)
- Patricia Facchinetti
- INSERM UMR 894, Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France
| | - Emilie Dorard
- INSERM UMR 894, Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France
| | - Vincent Contremoulins
- ImagoSeine, Institut Jacques Monod, UMR 7592, CNRS and Université Paris Diderot, Paris, France
| | | | | | - Véronique Sazdovitch
- Laboratoire de Neuropathologie Escourolle, Hôpital de la Salpêtrière, AP-HP, and Centre de Recherche de l'ICM (UPMC, INSERM UMR S 975, CNRS UMR 7225), Paris, France
| | - Chantal Guihenneuc-Jouyaux
- EA 4064, Université Paris Descartes, Sorbonne Paris Cité, Faculté des Sciences Pharmaceutiques et Biologiques, Paris, France
| | | | - Charles Duyckaerts
- Laboratoire de Neuropathologie Escourolle, Hôpital de la Salpêtrière, AP-HP, and Centre de Recherche de l'ICM (UPMC, INSERM UMR S 975, CNRS UMR 7225), Paris, France
| | - Bernadette Allinquant
- INSERM UMR 894, Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France.
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48
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XING SANLI, SHEN DINGZHU, CHEN CHUAN, WANG JIAN, LIU TE, YU ZHIHUA. Regulation of neuronal toxicity of β-amyloid oligomers by surface ATP synthase. Mol Med Rep 2013; 8:1689-94. [DOI: 10.3892/mmr.2013.1722] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 10/07/2013] [Indexed: 11/05/2022] Open
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49
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Stefani M, Rigacci S. Protein folding and aggregation into amyloid: the interference by natural phenolic compounds. Int J Mol Sci 2013; 14:12411-57. [PMID: 23765219 PMCID: PMC3709793 DOI: 10.3390/ijms140612411] [Citation(s) in RCA: 153] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 05/29/2013] [Accepted: 06/04/2013] [Indexed: 01/17/2023] Open
Abstract
Amyloid aggregation is a hallmark of several degenerative diseases affecting the brain or peripheral tissues, whose intermediates (oligomers, protofibrils) and final mature fibrils display different toxicity. Consequently, compounds counteracting amyloid aggregation have been investigated for their ability (i) to stabilize toxic amyloid precursors; (ii) to prevent the growth of toxic oligomers or speed that of fibrils; (iii) to inhibit fibril growth and deposition; (iv) to disassemble preformed fibrils; and (v) to favor amyloid clearance. Natural phenols, a wide panel of plant molecules, are one of the most actively investigated categories of potential amyloid inhibitors. They are considered responsible for the beneficial effects of several traditional diets being present in green tea, extra virgin olive oil, red wine, spices, berries and aromatic herbs. Accordingly, it has been proposed that some natural phenols could be exploited to prevent and to treat amyloid diseases, and recent studies have provided significant information on their ability to inhibit peptide/protein aggregation in various ways and to stimulate cell defenses, leading to identify shared or specific mechanisms. In the first part of this review, we will overview the significance and mechanisms of amyloid aggregation and aggregate toxicity; then, we will summarize the recent achievements on protection against amyloid diseases by many natural phenols.
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Affiliation(s)
- Massimo Stefani
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale Morgagni 50, Florence 50134, Italy; E-Mail:
- Research Centre on the Molecular Basis of Neurodegeneration, Viale Morgagni 50, Florence 50134, Italy
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +39-55-275-8307; Fax: +39-55-275-8905
| | - Stefania Rigacci
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale Morgagni 50, Florence 50134, Italy; E-Mail:
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50
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Cecchi C, Stefani M. The amyloid-cell membrane system. The interplay between the biophysical features of oligomers/fibrils and cell membrane defines amyloid toxicity. Biophys Chem 2013; 182:30-43. [PMID: 23820236 DOI: 10.1016/j.bpc.2013.06.003] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/03/2013] [Accepted: 06/03/2013] [Indexed: 12/14/2022]
Abstract
Amyloid cytotoxicity, structure and polymorphisms are themes of increasing importance. Present knowledge considers any peptide/protein able to undergo misfolding and aggregation generating intrinsically cytotoxic amyloids. It also describes growth and structure of amyloid fibrils and their possible disassembly, whereas reduced information is available on oligomer structure. Recent research has highlighted the importance of the environmental conditions as determinants of the amyloid polymorphisms and cytotoxicity. Another body of evidence describes chemical or biological surfaces as key sites of protein misfolding and aggregation or of interaction with amyloids and the resulting biochemical modifications inducing cell functional/viability impairment. In particular, the membrane lipid composition appears to modulate cell response to toxic amyloids, thus contributing to explain the variable vulnerability to the same amyloids of different cell types. Finally, a recent view describes amyloid toxicity as an emerging property dependent on a complex interplay between the biophysical features of early aggregates and the interacting cell membranes taken as a whole system.
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Affiliation(s)
- Cristina Cecchi
- Department of Biomedical Experimental and Clinical Sciences and Research Centre on the Molecular Basis of Neurodegeneration, University of Florence, Florence, Italy
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