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Condello C, Stöehr J. Aβ propagation and strains: Implications for the phenotypic diversity in Alzheimer's disease. Neurobiol Dis 2017; 109:191-200. [PMID: 28359847 DOI: 10.1016/j.nbd.2017.03.014] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/09/2017] [Accepted: 03/26/2017] [Indexed: 12/13/2022] Open
Abstract
The progressive nature of Alzheimer's disease (AD) is thought to occur, at least in part, by the self-replication and spreading of Aβ and Tau aggregates through a prion mechanism. Evidence now exists that structural variants of Aβ prions can propagate their distinct conformations through template-directed folding of naïve Aβ peptides. This notion implicates that the first self-propagating Aβ assembly to emerge in the brain dictates the conformation, anatomical spread and pace of subsequently formed deposits. It is hypothesized that a prion mechanism defines the molecular basis underlying the diverse clinicopathologic phenotypes observed across the spectrum of AD patients. Thus, distinct AD strains might require further sub-classification based on biochemical and structural characterization of aggregated Aβ. Here, we review the evidence for distinct, self-propagating Aβ strains, and discuss potential cellular mechanisms that might contribute to their manifestation. From this perspective, we also explore the implications of Aβ strains for current FDA-approved medical imaging probes and therapies for amyloid. Ultimately, the discovery of new molecular tools to differentiate Aβ strains and dissect the heterogeneity of AD may lead to the development of more informative diagnostics and strain-specific therapeutics.
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Affiliation(s)
- Carlo Condello
- Institute for Neurodegenerative Diseases, Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, United States
| | - Jan Stöehr
- Institute for Neurodegenerative Diseases, Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, United States.
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102
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Zolezzi JM, Inestrosa NC. Wnt/TLR Dialog in Neuroinflammation, Relevance in Alzheimer's Disease. Front Immunol 2017; 8:187. [PMID: 28286503 PMCID: PMC5323396 DOI: 10.3389/fimmu.2017.00187] [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] [Received: 11/29/2016] [Accepted: 02/09/2017] [Indexed: 12/22/2022] Open
Abstract
The innate immune system (IIS) represents the first line of defense against exogenous and endogenous harmful stimuli. Different types of pathogens and diverse molecules can activate the IIS via a ligand-receptor mechanism. Cytokine release, recruitment of immunocompetent cells, and inflammation constitute the initial steps in an IIS-mediated response. While balanced IIS activity can resolve a harmful event, an altered response, such as deficient or persistent IIS activity, will have a critical effect on organism homeostasis. In this regard, chronic IIS activation has been associated with a wide range of diseases, including chronic inflammatory disorders (inflammatory bowel disease, arthritis, chronic obstructive pulmonary disease, among others), cancer and, more recently, neurodegenerative disorders. The relevance of the immune response, particularly inflammation, in the context of neurodegeneration has motivated rigorous research focused on unveiling the mechanisms underlying this response. Knowledge regarding the molecular hallmarks of the innate immune response and understanding signaling pathway cross talk are critical for developing new therapeutic strategies aimed at modulating the neuroinflammatory response within the brain. In the present review, we discuss the IIS in the central nervous system, particularly the cross talk between the toll-like receptor-signaling cascade and the wingless-related MMTV integration site (Wnt) signaling pathway and its relevance in neurodegenerative disorders such as Alzheimer's disease.
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Affiliation(s)
- Juan M Zolezzi
- Centro de Envejecimiento y Regeneración (CARE-UC), Facultad de Ciencias Biológicas, Departamento de Biología Celular y Molecular, P. Universidad Católica de Chile , Santiago , Chile
| | - Nibaldo C Inestrosa
- Centro de Envejecimiento y Regeneración (CARE-UC), Facultad de Ciencias Biológicas, Departamento de Biología Celular y Molecular, P. Universidad Católica de Chile, Santiago, Chile; Centre for Healthy Brain Ageing, Faculty of Medicine, School of Psychiatry, University of New South Wales, Sydney, NSW, Australia; Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile
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103
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Nucleobindin 1 binds to multiple types of pre-fibrillar amyloid and inhibits fibrillization. Sci Rep 2017; 7:42880. [PMID: 28220836 PMCID: PMC5318909 DOI: 10.1038/srep42880] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 01/16/2017] [Indexed: 11/08/2022] Open
Abstract
During amyloid fibril formation, amyloidogenic polypeptides misfold and self assemble into soluble pre-fibrillar aggregates, i.e., protofibrils, which elongate and mature into insoluble fibrillar aggregates. An emerging class of chaperones, chaperone-like amyloid binding proteins (CLABPs), has been shown to interfere with aggregation of particular misfolded amyloid peptides or proteins. We have discovered that the calcium-binding protein nuclebindin-1 (NUCB1) is a novel CLABP. We show that NUCB1 inhibits aggregation of islet-amyloid polypeptide associated with type 2 diabetes mellitus, a-synuclein associated with Parkinson’s disease, transthyretin V30M mutant associated with familial amyloid polyneuropathy, and Aβ42 associated with Alzheimer’s disease by stabilizing their respective protofibril intermediates. Kinetic studies employing the modeling software AmyloFit show that NUCB1 affects both primary nucleation and secondary nucleation. We hypothesize that NUCB1 binds to the common cross-β-sheet structure of protofibril aggregates to “cap” and stabilize soluble macromolecular complexes. Transmission electron microscopy and atomic force microscopy were employed to characterize the size, shape and volume distribution of multiple sources of NUCB1-capped protofibrils. Interestingly, NUCB1 prevents Aβ42 protofibril toxicity in a cellular assay. NUCB1-stabilized amyloid protofibrils could be used as immunogens to prepare conformation-specific antibodies and as novel tools to develop screens for anti-protofibril diagnostics and therapeutics.
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104
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Hamm V, Héraud C, Bott JB, Herbeaux K, Strittmatter C, Mathis C, Goutagny R. Differential contribution of APP metabolites to early cognitive deficits in a TgCRND8 mouse model of Alzheimer's disease. SCIENCE ADVANCES 2017; 3:e1601068. [PMID: 28275722 PMCID: PMC5325539 DOI: 10.1126/sciadv.1601068] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 01/25/2017] [Indexed: 06/06/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative pathology commonly characterized by a progressive and irreversible deterioration of cognitive functions, especially memory. Although the etiology of AD remains unknown, a consensus has emerged on the amyloid hypothesis, which posits that increased production of soluble amyloid β (Aβ) peptide induces neuronal network dysfunctions and cognitive deficits. However, the relative failures of Aβ-centric therapeutics suggest that the amyloid hypothesis is incomplete and/or that the treatments were given too late in the course of AD, when neuronal damages were already too extensive. Hence, it is striking to see that very few studies have extensively characterized, from anatomy to behavior, the alterations associated with pre-amyloid stages in mouse models of AD amyloid pathology. To fulfill this gap, we examined memory capacities as well as hippocampal network anatomy and dynamics in young adult pre-plaque TgCRND8 mice when hippocampal Aβ levels are still low. We showed that TgCRND8 mice present alterations in hippocampal inhibitory networks and γ oscillations at this stage. Further, these mice exhibited deficits only in a subset of hippocampal-dependent memory tasks, which are all affected at later stages. Last, using a pharmacological approach, we showed that some of these early memory deficits were Aβ-independent. Our results could partly explain the limited efficacy of Aβ-directed treatments and favor multitherapy approaches for early symptomatic treatment for AD.
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Affiliation(s)
- Valentine Hamm
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Céline Héraud
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Jean-Bastien Bott
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Karine Herbeaux
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Carole Strittmatter
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Chantal Mathis
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Romain Goutagny
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
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105
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Lee TW, Tsang VWK, Loef EJ, Birch NP. Physiological and pathological functions of neuroserpin: Regulation of cellular responses through multiple mechanisms. Semin Cell Dev Biol 2017; 62:152-159. [PMID: 27639894 DOI: 10.1016/j.semcdb.2016.09.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 09/09/2016] [Accepted: 09/12/2016] [Indexed: 11/17/2022]
Abstract
It is 27 years since neuroserpin was first discovered in the nervous system and identified as a member of the serpin superfamily. Since that time potential roles for this serine protease inhibitor have been identified in neuronal and non-neuronal systems. Many are linked to inhibition of neuroserpin's principal enzyme target, tissue plasminogen activator (tPA), although some have been suggested to involve alternate non-inhibitory mechanisms. This review focuses mainly on the inhibitory roles of neuroserpin and discusses the evidence supporting tPA as the physiological target. While the major sites of neuroserpin expression are neural, endocrine and immune tissues, most progress on characterizing functional roles for neuroserpin have been in the brain. Roles in emotional behaviour, synaptic plasticity and neuroprotection in stroke and excitotoxicity models are discussed. Current knowledge on three neurological diseases associated with neuroserpin mutation or activity, Familial Encephalopathy with Neuroserpin Inclusion Bodies (FENIB), Alzheimer's disease and brain metastasis is presented. Finally, we consider mechanistic studies that have revealed a distinct inhibitory mechanism for neuroserpin and its possible implications for neuroserpin function.
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Affiliation(s)
- Tet Woo Lee
- School of Biological Sciences and Centre for Brain Research, University of Auckland, Auckland, New Zealand.
| | - Vicky W K Tsang
- School of Biological Sciences and Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - Evert Jan Loef
- School of Biological Sciences and Centre for Brain Research, University of Auckland, Auckland, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - Nigel P Birch
- School of Biological Sciences and Centre for Brain Research, University of Auckland, Auckland, New Zealand; Brain Research New Zealand, Rangahau Roro Aotearoa, Auckland, New Zealand.
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106
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Ren B, Zhang M, Hu R, Chen H, Wang M, Lin Y, Sun Y, Jia L, Liang G, Zheng J. Identification of a New Function of Cardiovascular Disease Drug 3-Morpholinosydnonimine Hydrochloride as an Amyloid-β Aggregation Inhibitor. ACS OMEGA 2017; 2:243-250. [PMID: 30023514 PMCID: PMC6044715 DOI: 10.1021/acsomega.6b00397] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 01/13/2017] [Indexed: 05/29/2023]
Abstract
Cardiovascular disease (CVD) and Alzheimer's disease (AD) have a mutual cause-and-effect relationship, and they share some common risk factors. Although numerous Food and Drug Administration (FDA)-approved drugs have been developed for CVD treatment, no drugs are clinically available for AD treatment. Given the common disease-causing factors and links between the two diseases and the well-demonstrated drugs for CVD, we propose to re-examine the new potential of the existing CVD drugs as amyloid-β (Aβ) inhibitors. 3-Morpholinosydnonimine hydrochloride (SIN-1) is an FDA-approved drug for inhibiting platelet aggregation in CVD. Herein, we examine the inhibition activity of SIN-1 on the aggregation and toxicity of Aβ1-42 using combined experimental and computational approaches. Collective experimental data from ThT, circular dichroism, and atomic force microscopy demonstrate that SIN-1 can effectively inhibit amyloid formation at every stage of Aβ aggregation by prolonging lag phase, slowing down aggregation rate, and reducing final fibril formation. The cell viability assay also shows that SIN-1 enables the protection of SH-SY5Y cells from Aβ-induced cell toxicity. Such an inhibition effect is attributed to interference with the structural transition of Aβ toward a β-sheet structure by SIN-1. Furthermore, molecular dynamic simulations confirm that SIN-1 preferentially binds to the C-terminal β-sheet grooves of an Aβ oligomer and consequently disrupts the β-sheet structure of Aβ and Aβ-Aβ association, explaining experimental observations. This work discovers a new function of SIN-1, making it a promising compound with dual protective roles in inhibiting both platelet and Aβ aggregations against CVD and AD.
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Affiliation(s)
- Baiping Ren
- Department
of Chemical & Biomolecular Engineering, The University of Akron, Akron, Ohio 44325, United States
- School
of Life Science and Biotechnology, Dalian
University of Technology, Dalian 116024, China
| | - Mingzhen Zhang
- Department
of Chemical & Biomolecular Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Rundong Hu
- Department
of Chemical & Biomolecular Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Hong Chen
- Department
of Chemical & Biomolecular Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Manli Wang
- Mingyuan
Staff-Worker Hospital of Xinjiang Oil Field Company, 789 Youhao Beilu, Urumqi, Xinjiang 830000, China
| | - Yufeng Lin
- Mingyuan
Staff-Worker Hospital of Xinjiang Oil Field Company, 789 Youhao Beilu, Urumqi, Xinjiang 830000, China
| | - Yan Sun
- Department
of Biochemical Engineering and Key Laboratory of Systems Bioengineering
of the Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Lingyun Jia
- School
of Life Science and Biotechnology, Dalian
University of Technology, Dalian 116024, China
| | - Guizhao Liang
- Department
of Chemical & Biomolecular Engineering, The University of Akron, Akron, Ohio 44325, United States
- Key
Laboratory of Biorheological Science and Technology, Ministry of Education,
School of Bioengineering, Chongqing University, Chongqing 400044, China
| | - Jie Zheng
- Department
of Chemical & Biomolecular Engineering, The University of Akron, Akron, Ohio 44325, United States
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107
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Hsu DC, Marshall GA. Primary and Secondary Prevention Trials in Alzheimer Disease: Looking Back, Moving Forward. Curr Alzheimer Res 2017; 14:426-440. [PMID: 27697063 PMCID: PMC5329133 DOI: 10.2174/1567205013666160930112125] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 09/10/2016] [Accepted: 09/22/2016] [Indexed: 12/20/2022]
Abstract
The field of Alzheimer disease (AD) prevention has been a culmination of basic science, clinical, and translational research. In the past three years since the new 2011 AD diagnostic guidelines, large-scale collaborative efforts have embarked on new clinical trials with the hope of someday preventing AD. This review will shed light on the historical and scientific contexts in which these trials were based on, as well as discuss potential challenges these trials may face in the coming years. Primary preventive measures, such as lifestyle, multidomain, medication, and supplemental interventions, will be analyzed. Secondary prevention as represented by disease-modifying interventions, such as antiamyloid therapy and pioglitazone, will also be reviewed. Finally, hypotheses on future directions for AD prevention trials will be proposed.
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Affiliation(s)
- David C. Hsu
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
- Center for Alzheimer Research and Treatment, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Gad A. Marshall
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
- Center for Alzheimer Research and Treatment, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
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108
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Mohamed LA, Zhu H, Mousa YM, Wang E, Qiu WQ, Kaddoumi A. Amylin Enhances Amyloid-β Peptide Brain to Blood Efflux Across the Blood-Brain Barrier. J Alzheimers Dis 2017; 56:1087-1099. [PMID: 28059785 PMCID: PMC5466167 DOI: 10.3233/jad-160800] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Findings from Alzheimer's disease (AD) mouse models showed that amylin treatment improved AD pathology and enhanced amyloid-β (Aβ) brain to blood clearance; however, the mechanism was not investigated. Using the Tg2576 AD mouse model, a single intraperitoneal injection of amylin significantly increased Aβ serum levels, and the effect was abolished by AC253, an amylin receptor antagonist, suggesting that amylin effect could be mediated by its receptor. Subsequent mechanistic studies showed amylin enhanced Aβ transport across a cell-based model of the blood-brain barrier (BBB), an effect that was abolished when the amylin receptor was inhibited by two amylin antagonists and by siRNA knockdown of amylin receptor Ramp3. To explain this finding, amylin effect on Aβ transport proteins expressed at the BBB was evaluated. Findings indicated that cells treated with amylin induced LRP1 expression, a major receptor involved in brain Aβ efflux, in plasma membrane fraction, suggesting intracellular translocation of LRP1 from the cytoplasmic pool. Increased LRP1 in membrane fraction could explain, at least in part, the enhanced uptake and transport of Aβ across the BBB. Collectively, our findings indicated that amylin induced Aβ brain to blood clearance through amylin receptor by inducing LRP1 subcellular translocation to the plasma membrane of the BBB endothelium.
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Affiliation(s)
- Loqman A. Mohamed
- Department of Basic Pharmaceutical Science, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
| | - Haihao Zhu
- Departments of Pharmacology & Experimental Therapeutics, Psychiatry, Boston University School of Medicine, Boston, MA, USA
| | - Youssef M. Mousa
- Department of Basic Pharmaceutical Science, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
| | - Erming Wang
- Departments of Pharmacology & Experimental Therapeutics, Psychiatry, Boston University School of Medicine, Boston, MA, USA
| | - Wei Qiao Qiu
- Departments of Pharmacology & Experimental Therapeutics, Psychiatry, Boston University School of Medicine, Boston, MA, USA
| | - Amal Kaddoumi
- Department of Basic Pharmaceutical Science, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
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109
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Tarazi H, Odeh RA, Al-Qawasmeh R, Yousef IA, Voelter W, Al-Tel TH. Design, synthesis and SAR analysis of potent BACE1 inhibitors: Possible lead drug candidates for Alzheimer's disease. Eur J Med Chem 2017; 125:1213-1224. [DOI: 10.1016/j.ejmech.2016.11.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 10/12/2016] [Accepted: 11/10/2016] [Indexed: 11/29/2022]
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110
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Metabotropic glutamate receptors and neurodegenerative diseases. Pharmacol Res 2017; 115:179-191. [DOI: 10.1016/j.phrs.2016.11.013] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 11/11/2016] [Accepted: 11/15/2016] [Indexed: 12/21/2022]
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111
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Hamada Y, Kiso Y. New directions for protease inhibitors directed drug discovery. Biopolymers 2016; 106:563-79. [PMID: 26584340 PMCID: PMC7161749 DOI: 10.1002/bip.22780] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 10/25/2015] [Accepted: 11/02/2015] [Indexed: 12/29/2022]
Abstract
Proteases play crucial roles in various biological processes, and their activities are essential for all living organisms-from viruses to humans. Since their functions are closely associated with many pathogenic mechanisms, their inhibitors or activators are important molecular targets for developing treatments for various diseases. Here, we describe drugs/drug candidates that target proteases, such as malarial plasmepsins, β-secretase, virus proteases, and dipeptidyl peptidase-4. Previously, we reported inhibitors of aspartic proteases, such as renin, human immunodeficiency virus type 1 protease, human T-lymphotropic virus type I protease, plasmepsins, and β-secretase, as drug candidates for hypertension, adult T-cell leukaemia, human T-lymphotropic virus type I-associated myelopathy, malaria, and Alzheimer's disease. Our inhibitors are also described in this review article as examples of drugs that target proteases. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 563-579, 2016.
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Affiliation(s)
- Yoshio Hamada
- Medicinal Chemistry LaboratoryKobe Pharmaceutical University, MotoyamakitaHigashinada‐kuKobe658‐8558Japan
| | - Yoshiaki Kiso
- Laboratory of Peptide Science, Nagahama Institute of Bio‐Science and TechnologyTamura‐choNagahama526‐0829Japan
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112
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Oikonomidi A, Lewczuk P, Kornhuber J, Smulders Y, Linnebank M, Semmler A, Popp J. Homocysteine metabolism is associated with cerebrospinal fluid levels of soluble amyloid precursor protein and amyloid beta. J Neurochem 2016; 139:324-332. [PMID: 27507672 DOI: 10.1111/jnc.13766] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 06/15/2016] [Accepted: 07/29/2016] [Indexed: 01/05/2023]
Abstract
Disturbed homocysteine metabolism may contribute to amyloidogenesis by modulating the amyloid precursor protein (APP) production and processing. The objective of this study was to investigate the relationships between cerebral amyloid production and both blood and cerebrospinal fluid (CSF) markers of the homocysteine metabolism. We assessed CSF concentrations of soluble APPα, soluble APPβ, and amyloid β1-42 (Aβ1-42), as well as plasma levels of homocysteine (Hcys), total vitamin B12, and folate, and CSF concentrations of homocysteine (Hcys-CSF), 5-methyltetrahydrofolate (5-MTHF), S-adenosylmethionine (SAM), and S-adenosylhomocysteine (SAH) in 59 subjects with normal cognition. Linear regression analyses were performed to assess associations between homocysteine metabolism parameters and amyloid production. The study was approved by the Ethical Committee of the University of Bonn. After controlling for age, gender, APOEe4 status, and albumin ratio (Qalb), higher Aβ1-42 CSF levels were associated with high Hcys and low vitamin B12 plasma levels as well as with high Hcys, high SAH, and low 5-MTHF CSF levels. Higher CSF concentrations of sAPPα and sAPPβ were associated with high SAH levels. The results suggest that disturbed homocysteine metabolism is related to increased CSF levels of sAPP forms and Aβ1-42, and may contribute to the accumulation of amyloid pathology in the brain. Disturbed homocysteine metabolism may contribute to amyloidogenesis by modulating the amyloid precursor protein (APP) production and processing. We found associations between CSF levels of soluble APP forms and Aβ1-42, and markers of the homocysteine metabolism in both plasma and CSF in adults with normal cognition. Disturbed homocysteine metabolism may represent a target for preventive and early disease-modifying interventions in Alzheimer's disease.
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Affiliation(s)
- Aikaterini Oikonomidi
- Department of Psychiatry, Division of Old Age Psychiatry, University Hospital of Lausanne, Lausanne, Switzerland
| | - Piotr Lewczuk
- Department of Psychiatry and Psychotherapy, University of Erlangen, Erlangen, Germany.,Department of Neurodegeneration Diagnostics, Medical University of Bialystok, Bialystok, Poland
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, University of Erlangen, Erlangen, Germany
| | - Yvo Smulders
- Department of Internal Medicine, VU University Medical Centre, Amsterdam, The Netherlands.,Institute for Cardiovascular Research ICaR-VU, VU University Medical Centre, Amsterdam, The Netherlands
| | - Michael Linnebank
- Department of Neurology, University Hospital Zurich, Zurich, Switzerland
| | - Alexander Semmler
- Department of Neurology, University Hospital Zurich, Zurich, Switzerland
| | - Julius Popp
- Department of Psychiatry, Division of Old Age Psychiatry, University Hospital of Lausanne, Lausanne, Switzerland. .,Department of Psychiatry and Psychotherapy, University of Bonn, Bonn, Germany.
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113
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Katsurabayashi S, Kawano H, Ii M, Nakano S, Tatsumi C, Kubota K, Takasaki K, Mishima K, Fujiwara M, Iwasaki K. Overexpression of Swedish mutant APP in aged astrocytes attenuates excitatory synaptic transmission. Physiol Rep 2016; 4:4/1/e12665. [PMID: 26733247 PMCID: PMC4760399 DOI: 10.14814/phy2.12665] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Amyloid precursor protein (APP), a type I transmembrane protein, has different aspects, namely, performs essential physiological functions and produces β‐amyloid peptide (Aβ). Overexpression of neuronal APP is responsible for synaptic dysfunction. In the central nervous system, astrocytes – a major glial cell type – have an important role in the regulation of synaptic transmission. Although APP is expressed in astrocytes, it remains unclear whether astrocytic overexpression of mutant APP affects synaptic transmission. In this study, the effect of astrocytic overexpression of a mutant APP on the excitatory synaptic transmission was investigated using coculture system of the transgenic (Tg) cortical astrocytes that express the human APP695 polypeptide with the double mutation K670N + M671L found in a large Swedish family with early onset Alzheimer's disease, and wild‐type hippocampal neuron. Significant secretion of Aβ 1–40 and 1–42 was observed in cultured cortical astrocytes from the Tg2576 transgenic mouse that genetically overexpresses Swedish mutant APP. Under the condition, Tg astrocytes did not affect excitatory synaptic transmission of cocultured wild‐type neurons. However, aged Tg astrocytes cultured for 9 weeks elicited a significant decrease in excitatory synaptic transmission in cocultured neurons. Moreover, a reduction in the number of readily releasable synaptic vesicles accompanied a decrease in the number of excitatory synapses in neurons cocultured with aged Tg astrocytes. These observations indicate that astrocytic expression of the mutant APP is involved in the downregulation of synaptic transmission with age.
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Affiliation(s)
- Shutaro Katsurabayashi
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Hiroyuki Kawano
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Miyuki Ii
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Sachiko Nakano
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Chihiro Tatsumi
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Kaori Kubota
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan A.I.G. Collaborative Research Institute for Aging and Brain Sciences, Fukuoka University, Fukuoka, Japan
| | - Kotaro Takasaki
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Kenichi Mishima
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan A.I.G. Collaborative Research Institute for Aging and Brain Sciences, Fukuoka University, Fukuoka, Japan
| | - Michihiro Fujiwara
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Katsunori Iwasaki
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan A.I.G. Collaborative Research Institute for Aging and Brain Sciences, Fukuoka University, Fukuoka, Japan
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114
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Sajadi A, Provost C, Pham B, Brouillette J. Neurodegeneration in an Animal Model of Chronic Amyloid-beta Oligomer Infusion Is Counteracted by Antibody Treatment Infused with Osmotic Pumps. J Vis Exp 2016:54215. [PMID: 27585306 PMCID: PMC5091865 DOI: 10.3791/54215] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Decline in hippocampal-dependent explicit memory (memory for facts and events) is one of the earliest clinical symptom of Alzheimer's disease (AD). It is well established that synapse loss and ensuing neurodegeneration are the best predictors for memory impairments in AD. Latest studies have emphasized the neurotoxic role of soluble amyloid-beta oligomers (Aβo) that begin to accumulate in the human brain approximately 10 to 15 yr before the clinical symptoms become apparent. Many reports indicate that soluble Aβo correlate with memory deficits in AD models and humans. The Aβo-induced neurodegeneration observed in neuronal and brain slice cultures has been more challenging to reproduce in many animal models. The model of repeated Aβo infusions shown here overcome this issue and allow addressing two key domains for developing new disease modifying therapies: identify biological markers to diagnose early AD, and determine the molecular mechanisms underpinning Aβo-induced memory deficits at the onset of AD. Since soluble Aβo aggregate relatively fast into insoluble Aβ fibrils that correlate poorly with the clinical state of patients, soluble Aβo are prepared freshly and injected once per day during six days to produce marked cell death in the hippocampus. We used cannula specially design for simultaneous infusions of Aβo and continuous infusion of Aβo antibody (6E10) in the hippocampus using osmotic pumps. This innovative in vivo method can now be used in preclinical studies to validate the efficiency of new AD therapies that might prevent the deposition and neurotoxicity of Aβo in pre-dementia patients.
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Affiliation(s)
- Ahmadali Sajadi
- Department of Pharmacology, Université de Montréal; Hôpital du Sacré-coeur de Montréal Research Center, Université de Montréal
| | - Chloé Provost
- Hôpital du Sacré-coeur de Montréal Research Center, Université de Montréal
| | - Brendon Pham
- Department of Neuroscience, Université de Montréal
| | - Jonathan Brouillette
- Department of Pharmacology, Université de Montréal; Hôpital du Sacré-coeur de Montréal Research Center, Université de Montréal;
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115
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Marshall KE, Vadukul DM, Dahal L, Theisen A, Fowler MW, Al-Hilaly Y, Ford L, Kemenes G, Day IJ, Staras K, Serpell LC. A critical role for the self-assembly of Amyloid-β1-42 in neurodegeneration. Sci Rep 2016; 6:30182. [PMID: 27443509 PMCID: PMC4957119 DOI: 10.1038/srep30182] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 06/28/2016] [Indexed: 11/23/2022] Open
Abstract
Amyloid β1-42 (Aβ1-42) plays a central role in Alzheimer’s disease. The link between structure, assembly and neuronal toxicity of this peptide is of major current interest but still poorly defined. Here, we explored this relationship by rationally designing a variant form of Aβ1-42 (vAβ1-42) differing in only two amino acids. Unlike Aβ1-42, we found that the variant does not self-assemble, nor is it toxic to neuronal cells. Moreover, while Aβ1-42 oligomers impact on synaptic function, vAβ1-42 does not. In a living animal model system we demonstrate that only Aβ1-42 leads to memory deficits. Our findings underline a key role for peptide sequence in the ability to assemble and form toxic structures. Furthermore, our non-toxic variant satisfies an unmet demand for a closely related control peptide for Aβ1-42 cellular studies of disease pathology, offering a new opportunity to decipher the mechanisms that accompany Aβ1-42-induced toxicity leading to neurodegeneration.
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Affiliation(s)
- Karen E Marshall
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK
| | - Devkee M Vadukul
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK
| | - Liza Dahal
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK
| | - Alina Theisen
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK
| | - Milena W Fowler
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK
| | - Youssra Al-Hilaly
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK.,College of Sciences, Chemistry Department, Al-Mustansiriyah University, Baghdad, Iraq
| | - Lenzie Ford
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK
| | - György Kemenes
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK
| | - Iain J Day
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK
| | - Kevin Staras
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK
| | - Louise C Serpell
- School of Life Sciences, University of Sussex, Falmer, BN1 9QG, UK
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116
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Wang Y, Miao Y, Mir AZ, Cheng L, Wang L, Zhao L, Cui Q, Zhao W, Wang H. Inhibition of beta-amyloid-induced neurotoxicity by pinocembrin through Nrf2/HO-1 pathway in SH-SY5Y cells. J Neurol Sci 2016; 368:223-30. [PMID: 27538638 DOI: 10.1016/j.jns.2016.07.010] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 07/03/2016] [Accepted: 07/08/2016] [Indexed: 11/26/2022]
Abstract
Amyloid beta peptide (Aβ) can cause neurotoxicity in Alzheimer's disease (AD). It evokes a cascade of oxidative damage to neurons. Pinocembrin (PCB), the most abundant flavonoid in propolis, has been proven to have neuroprotective effects in vivo and in vitro. In the present study, we investigated the neuroprotective effects of PCB on Aβ25-35-induced neurotoxicity. Exposure of SH-SY5Y cells to 25μM Aβ25-35 for 24h caused viability loss, apoptotic increase and reactive oxygen species (ROS) increase, pre-treatment with PCB for 4h significantly reduced the viability loss, apoptotic rate and attenuated Aβ-mediated ROS production. PCB strikingly inhibited Aβ25-35-induced mitochondrial dysfunctions, including lowered membrane potential, decreased Bcl-2/Bax ratio. In addition, PCB suppressed the release of cytochrome c and the cleavage of caspase-3. PCB treatment also resulted in an increase in Nrf2 protein levels and subsequent induction of heme oxygenase-1(HO-1) expression in SH-SY5Y cells. RNA interference-mediated knockdown of Nrf2 expression suppressed the PCB-induced HO-1 expression. Notably, we found that the HO-1 inhibitor zinc protoporphyrin IX (ZnPP) markedly diminished the neuroprotective effect of PCB against Aβ-mediated neurotoxicity. Taken together, these results indicated that PCB protects SH-SY5Y cells from Aβ25-35-induced neurotoxicity through activation of Nrf2/HO-1 pathways. Thus, activation of Nrf2/HO-1 pathways and inhibition of mitochondria-dependent apoptosis together may protect cells from Aβ25-35-induceded neurotoxicity.
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Affiliation(s)
- Yumin Wang
- Chifeng Medical College, Chifeng University, the Affiliated Hospital of Chifeng University, Chifeng 024005, PR China; Department of Oncology, the Affiliated Hospital of Chifeng University, Chifeng 024005, PR China
| | - Yingchun Miao
- Department of Geriatrics, Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing 100700, PR China
| | | | - Long Cheng
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100193, PR China
| | - Lina Wang
- Chifeng Medical College, Chifeng University, the Affiliated Hospital of Chifeng University, Chifeng 024005, PR China
| | - Linan Zhao
- Department of Central Lab, the Affiliated Hospital of Chifeng University, Chifeng 024005, PR China
| | - Qifu Cui
- Department of Neurology, the Affiliated Hospital of Chifeng University, Chifeng 024005, PR China
| | - Weili Zhao
- Department of Neurology, the Affiliated Hospital of Chifeng University, Chifeng 024005, PR China
| | - Hongquan Wang
- Chifeng Medical College, Chifeng University, the Affiliated Hospital of Chifeng University, Chifeng 024005, PR China; Department of Central Lab, the Affiliated Hospital of Chifeng University, Chifeng 024005, PR China; Department of Neurology, the Affiliated Hospital of Chifeng University, Chifeng 024005, PR China.
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117
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Bock HH, May P. Canonical and Non-canonical Reelin Signaling. Front Cell Neurosci 2016; 10:166. [PMID: 27445693 PMCID: PMC4928174 DOI: 10.3389/fncel.2016.00166] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 06/08/2016] [Indexed: 12/11/2022] Open
Abstract
Reelin is a large secreted glycoprotein that is essential for correct neuronal positioning during neurodevelopment and is important for synaptic plasticity in the mature brain. Moreover, Reelin is expressed in many extraneuronal tissues; yet the roles of peripheral Reelin are largely unknown. In the brain, many of Reelin's functions are mediated by a molecular signaling cascade that involves two lipoprotein receptors, apolipoprotein E receptor-2 (Apoer2) and very low density-lipoprotein receptor (Vldlr), the neuronal phosphoprotein Disabled-1 (Dab1), and members of the Src family of protein tyrosine kinases as crucial elements. This core signaling pathway in turn modulates the activity of adaptor proteins and downstream protein kinase cascades, many of which target the neuronal cytoskeleton. However, additional Reelin-binding receptors have been postulated or described, either as coreceptors that are essential for the activation of the "canonical" Reelin signaling cascade involving Apoer2/Vldlr and Dab1, or as receptors that activate alternative or additional signaling pathways. Here we will give an overview of canonical and alternative Reelin signaling pathways, molecular mechanisms involved, and their potential physiological roles in the context of different biological settings.
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Affiliation(s)
- Hans H Bock
- Clinic of Gastroenterology and Hepatology, Heinrich-Heine-University Düsseldorf Düsseldorf, Germany
| | - Petra May
- Clinic of Gastroenterology and Hepatology, Heinrich-Heine-University Düsseldorf Düsseldorf, Germany
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118
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Folic Acid Supplementation Mitigates Alzheimer's Disease by Reducing Inflammation: A Randomized Controlled Trial. Mediators Inflamm 2016; 2016:5912146. [PMID: 27340344 PMCID: PMC4909909 DOI: 10.1155/2016/5912146] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 03/06/2016] [Accepted: 04/04/2016] [Indexed: 11/18/2022] Open
Abstract
Background/Aims. Low serum folate levels can alter inflammatory reactions. Both phenomena have been linked to Alzheimer's disease (AD), but the effect of folic acid on AD itself is unclear. We quantified folate supplementation's effect on inflammation and cognitive function in patients with AD over the course of 6 months. Methods. Patients newly diagnosed with AD (age > 60 years; n = 121; mild to severe; international criteria) and being treated with donepezil were randomly assigned into two groups with (intervention group) or without (control group) supplemental treatment with folic acid (1.25 mg/d) for 6 months. The Mini-Mental State Examination (MMSE) was administered to all patients at baseline and follow-up, and blood samples were taken before and after treatment. We quantified serum folate, amyloid beta (Aβ), interleukin-6 (IL-6), tumor necrosis factor α (TNFα), plasma homocysteine (Hcy), S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), and the mRNA levels of presenilin (PS), IL-6, and TNFα in leukocytes. Data were analyzed using a repeated-measures mixed model. Results. The mean MMSE was slightly increased in the intervention group compared to that in the control group (P < 0.05). Posttreatment, plasma SAM and SAM/SAH levels were significantly higher (P < 0.05), while Aβ40, PS1-mRNA, and TNFα-mRNA levels were lower in the intervention group than in the control group (P < 0.05). The Aβ42/Aβ40 ratio was also higher in the intervention group (P < 0.05). Conclusions. Folic acid is beneficial in patients with AD. Inflammation may play an important role in the interaction between folic acid and AD. This trial is registered with clinical trial registration number ChiCTR-TRC-13003246.
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119
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Xu W, Weissmiller AM, White JA, Fang F, Wang X, Wu Y, Pearn ML, Zhao X, Sawa M, Chen S, Gunawardena S, Ding J, Mobley WC, Wu C. Amyloid precursor protein-mediated endocytic pathway disruption induces axonal dysfunction and neurodegeneration. J Clin Invest 2016; 126:1815-33. [PMID: 27064279 PMCID: PMC4855914 DOI: 10.1172/jci82409] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 02/24/2016] [Indexed: 12/17/2022] Open
Abstract
The endosome/lysosome pathway is disrupted early in the course of both Alzheimer's disease (AD) and Down syndrome (DS); however, it is not clear how dysfunction in this pathway influences the development of these diseases. Herein, we explored the cellular and molecular mechanisms by which endosomal dysfunction contributes to the pathogenesis of AD and DS. We determined that full-length amyloid precursor protein (APP) and its β-C-terminal fragment (β-CTF) act though increased activation of Rab5 to cause enlargement of early endosomes and to disrupt retrograde axonal trafficking of nerve growth factor (NGF) signals. The functional impacts of APP and its various products were investigated in PC12 cells, cultured rat basal forebrain cholinergic neurons (BFCNs), and BFCNs from a mouse model of DS. We found that the full-length wild-type APP (APPWT) and β-CTF both induced endosomal enlargement and disrupted NGF signaling and axonal trafficking. β-CTF alone induced atrophy of BFCNs that was rescued by the dominant-negative Rab5 mutant, Rab5S34N. Moreover, expression of a dominant-negative Rab5 construct markedly reduced APP-induced axonal blockage in Drosophila. Therefore, increased APP and/or β-CTF impact the endocytic pathway to disrupt NGF trafficking and signaling, resulting in trophic deficits in BFCNs. Our data strongly support the emerging concept that dysregulation of Rab5 activity contributes importantly to early pathogenesis of AD and DS.
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Affiliation(s)
- Wei Xu
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Neurosciences, UCSD, La Jolla, California, USA
| | | | - Joseph A. White
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, New York, USA
| | - Fang Fang
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Neurosciences, UCSD, La Jolla, California, USA
| | - Xinyi Wang
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yiwen Wu
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Matthew L. Pearn
- Department of Anesthesiology, UCSD, La Jolla, California, USA
- VA San Diego Healthcare System, San Diego, California, USA
| | - Xiaobei Zhao
- Department of Neurosciences, UCSD, La Jolla, California, USA
| | - Mariko Sawa
- Department of Neurosciences, UCSD, La Jolla, California, USA
| | - Shengdi Chen
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shermali Gunawardena
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, New York, USA
| | - Jianqing Ding
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | | | - Chengbiao Wu
- Department of Neurosciences, UCSD, La Jolla, California, USA
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120
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Patel A, Vasanthan V, Fu W, Fahlman RP, MacTavish D, Jhamandas JH. Histamine induces the production of matrix metalloproteinase-9 in human astrocytic cultures via H1-receptor subtype. Brain Struct Funct 2016; 221:1845-60. [PMID: 25682263 DOI: 10.1007/s00429-015-1007-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 02/07/2015] [Indexed: 10/24/2022]
Abstract
Accumulation of β-amyloid (Aβ) protein within the brain is a neuropathological hallmark of Alzheimer's disease (AD). One strategy to facilitate Aβ clearance from the brain is to promote Aβ catabolism. Matrix metalloproteinase-9 (MMP-9), a member of the family of Zn(+2)-containing endoproteases, known to be expressed and secreted by astrocytes, is capable of degrading Aβ. Histamine, a major aminergic brain neurotransmitter, stimulates the production of MMP-9 in keratinocytes through the histamine H1 receptor (H1R). In the present study, we show that histamine evokes a concentration- and calcium-dependent release of MMP-9 from human astrocytic U373 cells and primary cultures of human and rat astrocytes through the H1R subtype. Activation of H1R on astrocytes elevated intracellular levels of Ca(2+) that was accompanied by time-dependent increases in MAP kinase p44/p42 and PKC. In-cell western blots revealed dose-dependent increases in both enzymes, confirming involvement of these signal transduction pathways. We next investigated the extent of recombinant human MMP-9 (rhMMP-9) proteolytic activity on soluble oligomeric Aβ (soAβ). Mass spectrometry demonstrated time-dependent cleavage of soAβ (20 μM), but not another amyloidogenic protein amylin, upon incubation with rhMMP-9 (100 nM) at 1, 4 and 17 h. Furthermore, Western blots showed a shift in soAβ equilibrium toward lower order, less toxic monomeric species. In conclusion, both MAPK p44/p42 and PKC pathways appear to be involved in histamine-upregulated MMP-9 release via H1Rs in astrocytes. Furthermore, MMP-9 appears to cleave soAβ into less toxic monomeric species. Given the key role of histamine in MMP-9 release, this neurotransmitter may serve as a potential therapeutic target for AD.
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Affiliation(s)
- Aarti Patel
- Division of Neurology, Department of Medicine, Institute of Neuroscience and Mental Health, 530 Heritage Medical Research Centre, University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - Vishnu Vasanthan
- Division of Neurology, Department of Medicine, Institute of Neuroscience and Mental Health, 530 Heritage Medical Research Centre, University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - Wen Fu
- Division of Neurology, Department of Medicine, Institute of Neuroscience and Mental Health, 530 Heritage Medical Research Centre, University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - Richard P Fahlman
- Department of Biochemistry, University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - David MacTavish
- Division of Neurology, Department of Medicine, Institute of Neuroscience and Mental Health, 530 Heritage Medical Research Centre, University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - Jack H Jhamandas
- Division of Neurology, Department of Medicine, Institute of Neuroscience and Mental Health, 530 Heritage Medical Research Centre, University of Alberta, Edmonton, AB, T6G 2S2, Canada.
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Tan JW, Kim MK. Neuroprotective Effects of Biochanin A against β-Amyloid-Induced Neurotoxicity in PC12 Cells via a Mitochondrial-Dependent Apoptosis Pathway. Molecules 2016; 21:molecules21050548. [PMID: 27120593 PMCID: PMC6274559 DOI: 10.3390/molecules21050548] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 04/20/2016] [Accepted: 04/22/2016] [Indexed: 12/22/2022] Open
Abstract
Alzheimer's disease is considered one of the major neurodegenerative diseases and is characterized by the production of β-amyloid (Aβ) proteins and progressive loss of neurons. Biochanin A, a phytoestrogen compound found mainly in Trifolium pratense, was used in the present study as a potential alternative to estrogen replacement therapy via the investigation of its neuroprotective effects against Aβ25-35-induced toxicity, as well as of its potential mechanisms of action in PC12 cells. Exposure of these cells to the Aβ25-35 protein significantly increased cell viability loss and apoptosis. However, the effects induced by Aβ25-35 were markedly reversed in the present of biochanin A. Pretreatment with biochanin A attenuated the cytotoxic effect of the Aβ25-35 protein by decreasing viability loss, LDH release, and caspase activity in cells. Moreover, we found that expression of cytochrome c and Puma were reduced, alongside with the restoration of Bcl-2/Bax and Bcl-xL/Bax ratio in the presence of biochanin A, which led to a decrease in the apoptotic rate. These data demonstrate that mitochondria are involved in the protective effect of biochanin A against Aβ25-35 and that this drug attenuated Aβ25-35-induced PC12 cell injury and apoptosis by preventing mitochondrial dysfunction. Thus, biochanin A might raise a possibility as a potential therapeutic agent for Alzheimer's disease and other related neurodegenerative diseases.
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Affiliation(s)
- Ji Wei Tan
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Min Kyu Kim
- Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
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Zhao X, Liu C, Xu M, Li X, Bi K, Jia Y. Total Lignans of Schisandra chinensis Ameliorates Aβ1-42-Induced Neurodegeneration with Cognitive Impairment in Mice and Primary Mouse Neuronal Cells. PLoS One 2016; 11:e0152772. [PMID: 27035824 PMCID: PMC4818042 DOI: 10.1371/journal.pone.0152772] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 03/18/2016] [Indexed: 12/20/2022] Open
Abstract
Lignan compounds extracted from Schisandra chinensis (Turcz.) Baill. have been reported to possess various biological activities, and have potential in the treatment of Alzheimer’s disease. This study was designed to investigate the effects of total lignans of Schisandra chinensis (TLS) on cognitive function and neurodegeneration in the model of AD induced by Aβ1–42in vivo and in vitro. It was found that intragastric infusion with TLS (50 and 200 mg/kg) to Aβ1–42-induced mice significantly increased the number of avoidances in the shuttle-box test and swimming time in the target quadrant in the Morris water maze test. TLS at dose of 200 mg/kg significantly restored the activities of total antioxidant capacity (T-AOC), as well as the level of malondialdehyde (MDA) both in the hippocampus and cerebral cortex in mice. Results of histopathological examination indicated that TLS noticeably ameliorated the neurodegeneration in the hippocampus in mice. On the other hand, TLS (100 μM) could protect the Aβ1–42-induced primary mouse neuronal cells by blocking the decrease of mitochondrial membrane potential (MMP), change the expressions of Bcl-2 (important regulator in the mitochondria apoptosis pathway). Moreover, TLS also decreased the activity of β-secretase 1 (BACE1), crucial protease contributes to the hydrolysis of amyloid precursor protein (APP), and inhibited the expression of JKN/p38, which involved in the MAPKs signaling pathways in both mice and primary mouse neuronal cells. In summary, TLS might protect against cognitive deficits and neurodegeneration by releasing the damage of oxidative stress, inhibiting the expression of BACE1 and the MAPKs inflammatory signaling pathways.
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Affiliation(s)
- Xu Zhao
- School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Wenhua Road 103, Shenyang, 110016, China
| | - Chunmei Liu
- School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Wenhua Road 103, Shenyang, 110016, China
| | - Mengjie Xu
- School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Wenhua Road 103, Shenyang, 110016, China
| | - Xiaolong Li
- School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Wenhua Road 103, Shenyang, 110016, China
| | - Kaishun Bi
- School of Pharmacy, Shenyang Pharmaceutical University, Wenhua Road 103, Shenyang, 110016, China
| | - Ying Jia
- School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Wenhua Road 103, Shenyang, 110016, China
- * E-mail:
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Mohamed LA, Keller JN, Kaddoumi A. Role of P-glycoprotein in mediating rivastigmine effect on amyloid-β brain load and related pathology in Alzheimer's disease mouse model. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1862:778-787. [PMID: 26780497 PMCID: PMC4788561 DOI: 10.1016/j.bbadis.2016.01.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Revised: 01/13/2016] [Accepted: 01/14/2016] [Indexed: 01/01/2023]
Abstract
Recently, we showed that rivastigmine decreased amyloid-β (Aβ) brain load in aged rats by enhancing its clearance across the blood-brain barrier (BBB) via upregulation of P-glycoprotein (P-gp) and low-density lipoprotein receptor-related protein 1 (LRP1). Here, we extend our previous work to clarify P-gp role in mediating rivastigmine effect on Aβ brain levels and neuroprotection in a mouse model of Alzheimer's disease (AD) that expresses different levels of P-gp. APPSWE mice were bred with mdr1a/b knockout mice to produce littermates that were divided into three groups; APP(+)/mdr1(+/+), APP(+)/mdr1(+/-) and APP(+)/mdr1(-/-). Animals received rivastigmine treatment (0.3mg/kg/day) or vehicle for 8weeks using Alzet osmotic mini-pumps. ELISA analysis of brain homogenates for Aβ showed rivastigmine treatment to significantly decrease Aβ brain load in APP(+)/mdr1(+/+) by 25% and in APP(+)/mdr1(+/-) mice by 21% compared to their vehicle treated littermates, but not in APP(+)/mdr1(-/-) mice. In addition, rivastigmine reduced GFAP immunostaining of astrocytes by 50% and IL-1β brain level by 43% in APP(+)/mdr1(+/+) mice, however its effect was less pronounced in P-gp knockout mice. Moreover, rivastigmine demonstrated a P-gp expression dependent neuroprotective effect that was highest in APP(+)/mdr1(+/+)>APP(+)/mdr1(+/-)>APP(+)/mdr1(-/-) as determined by expression of synaptic markers PSD-95 and SNAP-25 using Western blot analysis. Collectively, our results suggest that P-gp plays important role in mediating rivastigmine non-cholinergic beneficial effects, including Aβ brain load reduction, neuroprotective and anti-inflammatory effects in the AD mouse models.
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Affiliation(s)
- Loqman A Mohamed
- Department of Basic Pharmaceutical Science, School of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Dr., Monroe, LA 71201, United States
| | - Jeffrey N Keller
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA 70808, United States
| | - Amal Kaddoumi
- Department of Basic Pharmaceutical Science, School of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Dr., Monroe, LA 71201, United States.
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Murtishaw AS, Heaney CF, Bolton MM, Sabbagh JJ, Langhardt MA, Kinney JW. Effect of acute lipopolysaccharide-induced inflammation in intracerebroventricular-streptozotocin injected rats. Neuropharmacology 2016; 101:110-22. [DOI: 10.1016/j.neuropharm.2015.08.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 08/03/2015] [Accepted: 08/26/2015] [Indexed: 12/25/2022]
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Pomilio C, Pavia P, Gorojod RM, Vinuesa A, Alaimo A, Galvan V, Kotler ML, Beauquis J, Saravia F. Glial alterations from early to late stages in a model of Alzheimer's disease: Evidence of autophagy involvement in Aβ internalization. Hippocampus 2016; 26:194-210. [PMID: 26235241 PMCID: PMC5467976 DOI: 10.1002/hipo.22503] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2015] [Indexed: 01/19/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease without effective therapy. Brain amyloid deposits are classical histopathological hallmarks that generate an inflammatory reaction affecting neuronal and glial function. The identification of early cell responses and of brain areas involved could help to design new successful treatments. Hence, we studied early alterations of hippocampal glia and their progression during the neuropathology in PDAPP-J20 transgenic mice, AD model, at 3, 9, and 15 months (m) of age. At 3 m, before deposits formation, microglial Iba1+ cells from transgenic mice already exhibited signs of activation and larger soma size in the hilus, alterations appearing later on stratum radiatum. Iba1 immunohistochemistry revealed increased cell density and immunoreactive area in PDAPP mice from 9 m onward selectively in the hilus, in coincidence with prominent amyloid Congo red + deposition. At pre-plaque stages, GFAP+ astroglia showed density alterations while, at an advanced age, the presence of deposits was associated with important glial volume changes and apparently being intimately involved in amyloid degradation. Astrocytes around plaques were strongly labeled for LC3 until 15 m in Tg mice, suggestive of increased autophagic flux. Moreover, β-Amyloid fibrils internalization by astrocytes in in vitro conditions was dependent on autophagy. Co-localization of Iba1 with ubiquitin or p62 was exclusively found in microglia contacting deposits from 9 m onward, suggesting torpid autophagy. Our work characterizes glial changes at early stages of the disease in PDAPP-J20 mice, focusing on the hilus as an especially susceptible hippocampal subfield, and provides evidence that glial autophagy could play a role in amyloid processing at advanced stages.
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Affiliation(s)
- Carlos Pomilio
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Instituto De Biologia Y Medicina Experimental Conicet, Buenos Aires, Argentina
| | - Patricio Pavia
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Instituto De Biologia Y Medicina Experimental Conicet, Buenos Aires, Argentina
| | - Roxana Mayra Gorojod
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, IQUIBICEN-Conicet, Buenos Aires, Argentina
| | - Angeles Vinuesa
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Instituto De Biologia Y Medicina Experimental Conicet, Buenos Aires, Argentina
| | - Agustina Alaimo
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, IQUIBICEN-Conicet, Buenos Aires, Argentina
| | - Veronica Galvan
- Department of Physiology, Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center, San Antonio, Texas
| | - Monica Lidia Kotler
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, IQUIBICEN-Conicet, Buenos Aires, Argentina
| | - Juan Beauquis
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Instituto De Biologia Y Medicina Experimental Conicet, Buenos Aires, Argentina
| | - Flavia Saravia
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Instituto De Biologia Y Medicina Experimental Conicet, Buenos Aires, Argentina
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Abstract
This chapter will focus on the descriptive, analytic, and intervention-oriented epidemiology of dementia and its most frequent etiologic type due to Alzheimer's disease. The chapter opens with a brief presentation of the concept of dementia, followed by the presentation of dementia of the Alzheimer type (DAT), including natural history, clinical manifestation, neuropathology, medical prognosis, and management. Further, the chapter presents the prevalence and incidence of dementia, with special consideration of secular trends in prevalence and incidence of DAT, and prognosis of the socioeconomic impact of dementia. Thereafter the main risk factors for DAT are covered. The chapter also addresses the results of ongoing therapeutic and preventive intervention trials for DAT. Finally, the future challenges of the epidemiology of dementia with a focus on the impact of the new diagnostic criteria for neurocognitive disorders, as well as the development of biomarkers for DAT and other types of dementia, will be briefly discussed.
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Affiliation(s)
- S F Sacuiu
- Department of Neuropsychiatry, Sahlgrenska University Hospital and Department of Psychiatry and Neurochemistry, University of Gothenburg Institute of Neuroscience and Physiology, Gothenburg, Sweden.
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127
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Why therapies for Alzheimer's disease do not work: Do we have consensus over the path to follow? Ageing Res Rev 2016; 25:70-84. [PMID: 26375861 DOI: 10.1016/j.arr.2015.09.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 09/09/2015] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease (AD) represents a personal tragedy of enormous magnitude, which imposes a daunting worldwide challenge for health-care providers and society as well. In last five decades, global research in clinics and laboratories has illuminated many features of this sinister and eventually fatal disease. Notwithstanding this development, the Alzheimer's research apparently has come across a phase of disappointment and a little reservation about the direction to follow. Persistently distressing controversies and a significant number of missing facts shed further uncertainty about the path forward. A detailed description of some of the main controversies in AD research may assist the field towards finding a resolution. Here I reviewed some alarming concerns or controversies related to these primary issues and emphasized on a possible mechanism to settle them.
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128
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Feng B, Hu P, Chen J, Liu Q, Li X, Du Y. Analysis of Differentially Expressed Genes Associated With Alzheimer's Disease Based on Bioinformatics Methods. Am J Alzheimers Dis Other Demen 2015; 30:746-51. [PMID: 24965283 PMCID: PMC10852745 DOI: 10.1177/1533317514537548] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To screen differentially expressed genes (DEGs) of Alzheimer's disease (AD). METHODS The gene expression profile (GSE26972) of AD was downloaded from Gene Expression Omnibus database. The DEGs were mapped to protein-protein interaction (PPI) data for acquiring the potential PPI relationship. The coexpressed significance of a gene pair in AD was determined. Then significantly enriched Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of DEGs were analyzed based on database for annotation visualization and integrated discovery tool. RESULTS The PPI network showed 7 upregulated genes and 4 downregulated genes that might play meaningful functional roles in AD. Meanwhile, 3 significantly enriched KEGG pathways as well as several significant GO terms (included α-actinin binding, interleukin 33 receptor activity, and telethonin binding) were identified. CONCLUSIONS The screened DEGs have the potential to become candidate target molecules to monitor, diagnose, and treat AD.
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Affiliation(s)
- Bo Feng
- Department of Neurology, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong PR China Department of Neurology, Hospital Affiliated to Binzhou medical University, Binzhou, PR China
| | - Peng Hu
- Department of Spine, Hospital Affiliated to Binzhou medical University, Binzhou, PR China
| | - Jinbo Chen
- Department of Neurology, Hospital Affiliated to Binzhou medical University, Binzhou, PR China
| | - Qingxin Liu
- Department of Neurology, Hospital Affiliated to Binzhou medical University, Binzhou, PR China
| | - Xizhi Li
- Department of Neurology, Hospital Affiliated to Binzhou medical University, Binzhou, PR China
| | - Yifeng Du
- Department of Neurology, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong PR China
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129
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Suttkus A, Holzer M, Morawski M, Arendt T. The neuronal extracellular matrix restricts distribution and internalization of aggregated Tau-protein. Neuroscience 2015; 313:225-35. [PMID: 26621125 DOI: 10.1016/j.neuroscience.2015.11.040] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 11/13/2015] [Accepted: 11/17/2015] [Indexed: 12/30/2022]
Abstract
Alzheimer's disease (AD) is a chronic degenerative disorder characterized by fibrillary aggregates of Aß and Tau-protein. Formation and progression of these pathological hallmarks throughout the brain follow a specific spatio-temporal pattern which provides the basis for neuropathological staging. Previously, we could demonstrate that cortical and subcortical neurons are less frequently affected by neurofibrillary degeneration if they are enwrapped by a specialized form of the hyaluronan-based extracellular matrix (ECM), the so called 'perineuronal net' (PN). PNs are composed of large aggregating chondroitin sulfate proteoglycans connected to a hyaluronan backbone, stabilized by link proteins and cross-linked via tenascin-R. Recently, PN-associated neurons were shown to be better protected against iron-induced neurodegeneration compared to neurons without PN, indicating a neuroprotective function. Here, we investigated the role of PNs in distribution and internalization of exogenous Tau-protein by using organotypic slice cultures of wildtype mice as well as mice lacking the ECM-components aggrecan, HAPLN1 or tenascin-R. We could demonstrate that PNs restrict both distribution and internalization of Tau. Accordingly, PN-ensheathed neurons were less frequently affected by Tau-internalization, than neurons without PN. Finally, the PNs as well as their three investigated components were shown to modulate the processes of distribution as well as internalization of Tau.
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Affiliation(s)
- A Suttkus
- University of Leipzig, Department for Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute of Brain Research, Liebigstraße 19, 04103 Leipzig, Germany.
| | - M Holzer
- University of Leipzig, Department for Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute of Brain Research, Liebigstraße 19, 04103 Leipzig, Germany
| | - M Morawski
- University of Leipzig, Department for Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute of Brain Research, Liebigstraße 19, 04103 Leipzig, Germany
| | - T Arendt
- University of Leipzig, Department for Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute of Brain Research, Liebigstraße 19, 04103 Leipzig, Germany
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Chen W, Gamache E, Rosenman DJ, Xie J, Lopez MM, Li YM, Wang C. Familial Alzheimer's mutations within APPTM increase Aβ42 production by enhancing accessibility of ε-cleavage site. Nat Commun 2015; 5:3037. [PMID: 24390130 DOI: 10.1038/ncomms4037] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 11/29/2013] [Indexed: 02/08/2023] Open
Abstract
The high Aβ42/Aβ40 production ratio is a hallmark of familial Alzheimer's disease, which can be caused by mutations in the amyloid precursor protein (APP). The C-terminus of Aβ is generated by γ-secretase cleavage within the transmembrane domain of APP (APPTM), a process that is primed by an initial ε-cleavage at either T48 or L49, resulting in subsequent production of Aβ42 or Aβ40, respectively. Here we solve the dimer structures of wild-type APPTM (AAPTM WT) and mutant APPTM (FAD mutants V44M) with solution NMR. The right-handed APPTM helical dimer is mediated by GXXXA motif. From the NMR structural and dynamic data, we show that the V44M and V44A mutations can selectively expose the T48 site by weakening helical hydrogen bonds and increasing hydrogen-deuterium exchange rate (kex). We propose a structural model in which FAD mutations (V44M and V44A) can open the T48 site γ-secretase for the initial ε-cleavage, and consequently shift cleavage preference towards Aβ42.
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Affiliation(s)
- Wen Chen
- Department of Biological Sciences, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
| | - Eric Gamache
- Department of Biological Sciences, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
| | - David J Rosenman
- Department of Biological Sciences, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
| | - Jian Xie
- Department of Biological Sciences, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
| | - Maria M Lopez
- Department of Biological Sciences, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
| | - Yue-Ming Li
- Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, USA
| | - Chunyu Wang
- Department of Biological Sciences, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
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131
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Majd S, Power JH, Grantham HJM. Neuronal response in Alzheimer's and Parkinson's disease: the effect of toxic proteins on intracellular pathways. BMC Neurosci 2015; 16:69. [PMID: 26499115 PMCID: PMC4619058 DOI: 10.1186/s12868-015-0211-1] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 10/13/2015] [Indexed: 01/09/2023] Open
Abstract
Accumulation of protein aggregates is the leading cause of cellular dysfunction in neurodegenerative disorders. Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease, Prion disease and motor disorders such as amyotrophic lateral sclerosis, present with a similar pattern of progressive neuronal death, nervous system deterioration and cognitive impairment. The common characteristic is an unusual misfolding of proteins which is believed to cause protein deposition and trigger degenerative signals in the neurons. A similar clinical presentation seen in many neurodegenerative disorders suggests the possibility of shared neuronal responses in different disorders. Despite the difference in core elements of deposits in each neurodegenerative disorder, the cascade of neuronal reactions such as activation of glycogen synthase kinase-3 beta, mitogen-activated protein kinases, cell cycle re-entry and oxidative stress leading to a progressive neurodegeneration are surprisingly similar. This review focuses on protein toxicity in two neurodegenerative diseases, AD and PD. We reviewed the activated mechanisms of neurotoxicity in response to misfolded beta-amyloid and α-synuclein, two major toxic proteins in AD and PD, leading to neuronal apoptosis. The interaction between the proteins in producing an overlapping pathological pattern will be also discussed.
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Affiliation(s)
- Shohreh Majd
- Centre for Neuroscience and Paramedic Unit, School of Medicine, Flinders University of South Australia, Adelaide, SA, 5042, Australia.
| | - John H Power
- Department of Human Physiology, School of Medicine, Flinders University of South Australia, Adelaide, SA, 5042, Australia.
| | - Hugh J M Grantham
- Centre for Neuroscience and Paramedic Unit, School of Medicine, Flinders University of South Australia, Adelaide, SA, 5042, Australia.
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132
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Shah DJ, Rohlfing F, Anand S, Johnson WE, Alvarez MTB, Cobell J, King J, Young SA, Kauwe JS, Graves SW. Discovery and Subsequent Confirmation of Novel Serum Biomarkers Diagnosing Alzheimer’s Disease. J Alzheimers Dis 2015; 49:317-27. [DOI: 10.3233/jad-150498] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Dipti Jigar Shah
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA
| | | | - Swati Anand
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA
| | - W. Evan Johnson
- Division of Computational Biomedicine, Boston University School of Medicine, Boston University, Boston, MA, USA
| | | | - Jesse Cobell
- Department of Biology, Brigham Young University, Provo, UT, USA
| | - Jackson King
- Department of Biology, Brigham Young University, Provo, UT, USA
| | - Sydney A. Young
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA
| | - John S.K. Kauwe
- Department of Biology, Brigham Young University, Provo, UT, USA
| | - Steven W. Graves
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA
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133
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Zhang Q, Zhao JJ, Xu J, Feng F, Qu W. Medicinal uses, phytochemistry and pharmacology of the genus Uncaria. JOURNAL OF ETHNOPHARMACOLOGY 2015; 173:48-80. [PMID: 26091967 DOI: 10.1016/j.jep.2015.06.011] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 05/31/2015] [Accepted: 06/05/2015] [Indexed: 05/26/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The genus Uncaria belongs to the family Rubiaceae, which mainly distributed in tropical regions, such as Southeast Asia, Africa and Southeast America. Their leaves and hooks have long been thought to have healing powers and are already being tested as a treatment for asthma, cancer, cirrhosis, diabetes, hypertension, stroke and rheumatism. The present review aims to provide systematically reorganized information on the ethnopharmacology, phytochemistry and pharmacology of the genus Uncaria to support for further therapeutic potential of this genus. To better understanding this genus, information on the stereo-chemistry and structure-activity relationships in indole alkaloids is also represented. MATERIAL AND METHODS The literature study of this review is based on various databases search (SCIFinder, Science Direct, CNKI, Wiley online library, Spring Link, Web of Science, PubMed, Wanfang Data, Medalink, Google scholar, ACS, Tropicos, Council of Heads of Australasian Herbaria, The New York Botanical Garden, African Plants Database at Genera Botanical Garden, The Plant List and SEINet) and library search for Biological Abstract and some local books on ethnopharmacology. RESULTS 19 species of the genus Uncaria are found to be important folk medicines in China, Malaysia, Phillippines, Africa and Southeast America, etc, and have been served for the treatment of asthma, rheumatism, hyperpyrexia, hypertension and headaches, etc. More than 200 compounds have been isolated from Uncaria, including indole alkaloids, triterpenes, flavonoids, phenols, phenylpropanoids, etc. As characteristic constituents, indole alkaloids have been considered as main efficacy component for hypertension, epilepsy, depressant, Parkinson's disease and Alzheimer's disease. In addition, pharmacokinetic and metabolism investigation reveal that the indole alkaloids are likely to be absorbed, metabolized and excreted at early time points. Moreover, the specific inhibition of CYP isozymes can regulate their hydroxylation metabolites at C-10 and C-11. CONCLUSION Preliminary investigations on pharmacological properties of the Uncaria species have enlightened their efficacious remedy for hypertension, asthma, cancer, diabetes, rheumatism and neurodegenerative diseases. To ensure the safety and effectiveness in clinical application, research on bioactive compounds, pharmacological mechanisms and toxicity of the genus Uncaria as well as the stereo-chemistry and structure-activity relationships of indole alkaloids seem very important.
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Affiliation(s)
- Qian Zhang
- Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 210009, China
| | - Jiao Jiao Zhao
- Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 210009, China
| | - Jian Xu
- Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 210009, China
| | - Feng Feng
- Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 210009, China.
| | - Wei Qu
- Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 210009, China.
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134
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Gondard E, Chau HN, Mann A, Tierney TS, Hamani C, Kalia SK, Lozano AM. Rapid Modulation of Protein Expression in the Rat Hippocampus Following Deep Brain Stimulation of the Fornix. Brain Stimul 2015; 8:1058-64. [PMID: 26321354 DOI: 10.1016/j.brs.2015.07.044] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 07/24/2015] [Accepted: 07/29/2015] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The forniceal area is currently being evaluated as a target for deep brain stimulation (DBS) to improve cognitive function in patients with Alzheimer's disease. The molecular changes at downstream targets within the stimulated circuit are unknown. OBJECTIVE To analyze the modulation of hippocampal protein expression following 1 h of fornix DBS in the rat. METHODS Animals underwent bilateral forniceal DBS for 1 h and sacrificed at different time-points after the initiation of the stimulation (1 h, 2.5 h, 5 h, 25 h). Bilateral hippocampi were isolated for western blot analyses. RESULTS Forniceal DBS led to a dramatic elevation of cFos post-stimulation, suggesting that forniceal DBS activates the hippocampus. There was also a significant increase in candidate proteins including several trophic factors, such as brain derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) but not glial cell-derived neurotrophic factor (GDNF). There was in addition, increased expression of the synaptic markers growth associated protein 43 (GAP-43), synaptophysin and α-synuclein. No changes were observed at the studied time-points in Alzheimer's-related proteins including amyloid precursor protein (APP), tau, phosphorylated tau (ptau), or selected chaperone proteins (HSP40, HSP70 and CHIP). CONCLUSIONS Forniceal DBS triggers hippocampal activity and rapidly modulate the expression of neurotrophic factors and markers of synaptic plasticity known to play key roles in memory processing. The clinical effects of DBS of the fornix may, in part, be mediated by producing changes in the expression of these proteins.
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Affiliation(s)
- Elise Gondard
- Toronto Western Research Institute, Krembil Discovery Tower, University Health Network, 60 Leonard Street, Toronto, ON, M5T 2S8, Canada
| | - Hien N Chau
- Toronto Western Research Institute, Krembil Discovery Tower, University Health Network, 60 Leonard Street, Toronto, ON, M5T 2S8, Canada
| | - Amandeep Mann
- Toronto Western Research Institute, Krembil Discovery Tower, University Health Network, 60 Leonard Street, Toronto, ON, M5T 2S8, Canada
| | - Travis S Tierney
- Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA
| | - Clement Hamani
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada; Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University of Toronto, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada
| | - Suneil K Kalia
- Toronto Western Research Institute, Krembil Discovery Tower, University Health Network, 60 Leonard Street, Toronto, ON, M5T 2S8, Canada; Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University of Toronto, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada
| | - Andres M Lozano
- Toronto Western Research Institute, Krembil Discovery Tower, University Health Network, 60 Leonard Street, Toronto, ON, M5T 2S8, Canada; Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University of Toronto, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada.
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135
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Hussein RM, Hashem RM, Rashed LA. Evaluation of the amyloid beta-GFP fusion protein as a model of amyloid beta peptides-mediated aggregation: a study of DNAJB6 chaperone. Front Mol Neurosci 2015; 8:40. [PMID: 26283911 PMCID: PMC4515555 DOI: 10.3389/fnmol.2015.00040] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 07/13/2015] [Indexed: 12/16/2022] Open
Abstract
Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized by the accumulation and aggregation of extracellular amyloid β (Aβ) peptides and intracellular aggregation of hyper-phosphorylated tau protein. Recent evidence indicates that accumulation and aggregation of intracellular amyloid β peptides may also play a role in disease pathogenesis. This would suggest that intracellular Heat Shock Proteins (HSP) that maintain cellular protein homeostasis might be candidates for disease amelioration. We recently found that DNAJB6, a member of DNAJ family of heat shock proteins, effectively prevented the aggregation of short aggregation-prone peptides containing large poly glutamines (associated with CAG repeat diseases) both in vitro and in cells. Moreover, recent in vitro data showed that DNAJB6 can delay the aggregation of Aβ42 peptides. In this study, we investigated the ability of DNAJB6 to prevent the aggregation of extracellular and intracellular Aβ peptides using transfection of human embryonic kidney 293 (HEK293) cells with Aβ-green fluorescent protein (GFP) fusion construct and performing western blotting and immunofluorescence techniques. We found that DNAJB6 indeed suppresses Aβ-GFP aggregation, but not seeded aggregation initiated by extracellular Aβ peptides. Unexpectedly and unlike what we found for peptide-mediated aggregation, DNAJB6 required interaction with HSP70 to prevent the aggregation of the Aβ-GFP fusion protein and its J-domain was crucial for its anti-aggregation effect. In addition, other DNAJ proteins as well as HSPA1a overexpression also suppressed Aβ-GFP aggregation efficiently. Our findings suggest that Aβ aggregation differs from poly glutamine (Poly Q) peptide induced aggregation in terms of chaperone handling and sheds doubt on the usage of Aβ-GFP fusion construct for studying Aβ peptide aggregation in cells.
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Affiliation(s)
- Rasha M Hussein
- Faculty of Pharmacy, Department of Biochemistry, Beni-Suef University Beni-Suef, Egypt
| | - Reem M Hashem
- Faculty of Pharmacy, Department of Biochemistry, Beni-Suef University Beni-Suef, Egypt
| | - Laila A Rashed
- Kasr Al Ainy Faculty of Medicine, Department of Medical Biochemistry, Cairo University Cairo, Egypt
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136
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Norvin D, Kim G, Baker-Nigh A, Geula C. Accumulation and age-related elevation of amyloid-β within basal forebrain cholinergic neurons in the rhesus monkey. Neuroscience 2015; 298:102-11. [DOI: 10.1016/j.neuroscience.2015.04.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 03/31/2015] [Accepted: 04/06/2015] [Indexed: 11/29/2022]
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137
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Li L, Du J, Zou L, Xia H, Wu T, Kim Y, Lee Y. The Neuroprotective Effects of Decursin Isolated from Angelica gigas Nakai Against Amyloid β-Protein-Induced Apoptosis in PC 12 Cells via a Mitochondria-Related Caspase Pathway. Neurochem Res 2015; 40:1555-62. [PMID: 26077922 DOI: 10.1007/s11064-015-1623-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 05/19/2015] [Accepted: 05/20/2015] [Indexed: 11/24/2022]
Abstract
Decursin, purified from Angelica gigas Nakai, has been proven to exert neuroprotective property. Previous study revealed decursin protected the PC12 cells from Aβ25-35-induced oxidative cytotoxicity. The present study aimed to investigate whether decursin could protect PC12 cells from apoptosis caused by Aβ. Our results indicated that pretreatment of PC12 cells with decursin significantly inhibited Aβ25-35-induced cytotoxicity and apoptosis. The mechanism of action is likely to reverse Aβ25-35-induced mitochondrial dysfunction, including the reduction of mitochondrial membrane potential, the inhibition of reactive oxygen species production, and the decrease of mitochondrial release of cytochrome c in PC12 cells. In addition, decursin significantly suppressed the activity of caspase-3 and moderated the ratio of Bcl-2/Bax induced by Aβ25-35. These findings indicate that decursin exerts a neuroprotective effect against Aβ25-35-induced neurotoxicity in PC12 cells, at least in part, via suppressing the mitochondrial pathway of cellular apoptosis.
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Affiliation(s)
- Li Li
- Dongguan Scientific Research Center, Guangdong Medical University, Dongguan, 523-808, China,
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138
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Herrup K. The case for rejecting the amyloid cascade hypothesis. Nat Neurosci 2015; 18:794-9. [PMID: 26007212 DOI: 10.1038/nn.4017] [Citation(s) in RCA: 501] [Impact Index Per Article: 55.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 04/09/2015] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD) is a biologically complex neurodegenerative dementia. Nearly 20 years ago, with the combination of observations from biochemistry, neuropathology and genetics, a compelling hypothesis known as the amyloid cascade hypothesis was formulated. The core of this hypothesis is that it is pathological accumulations of amyloid-β, a peptide fragment of a membrane protein called amyloid precursor protein, that act as the root cause of AD and initiate its pathogenesis. Yet, with the passage of time, growing amounts of data have accumulated that are inconsistent with the basically linear structure of this hypothesis. And while there is fear in the field over the consequences of rejecting it outright, clinging to an inaccurate disease model is the option we should fear most. This Perspective explores the proposition that we are over-reliant on amyloid to define and diagnose AD and that the time has come to face our fears and reject the amyloid cascade hypothesis.
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Affiliation(s)
- Karl Herrup
- 1] Division of Life Science, Hong Kong University of Science and Technology, Kowloon, Hong Kong. [2] State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Kowloon, Hong Kong
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139
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Mohamed LA, Qosa H, Kaddoumi A. Age-Related Decline in Brain and Hepatic Clearance of Amyloid-Beta is Rectified by the Cholinesterase Inhibitors Donepezil and Rivastigmine in Rats. ACS Chem Neurosci 2015; 6:725-36. [PMID: 25782004 PMCID: PMC5248655 DOI: 10.1021/acschemneuro.5b00040] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
In Alzheimer's disease (AD), accumulation of brain amyloid-β (Aβ) depends on imbalance between production and clearance of Aβ. Several pathways for Aβ clearance have been reported including transport across the blood-brain barrier (BBB) and hepatic clearance. The incidence of AD increases with age and failure of Aβ clearance correlates with AD. The cholinesterase inhibitors (ChEIs) donepezil and rivastigmine are used to ease the symptoms of dementia associated with AD. Besides, both drugs have been reported to provide neuroprotective and disease-modifying effects. Here, we investigated the effect of ChEIs on age-related reduced Aβ clearance. Findings from in vitro and in vivo studies demonstrated donepezil and rivastigmine to enhance (125)I-Aβ40 clearance. Also, the increase in brain and hepatic clearance of (125)I-Aβ40 was more pronounced in aged compared to young rats, and was associated with significant reduction in brain Aβ endogenous levels determined by ELISA. Furthermore, the enhanced clearance was concomitant with up-regulation in the expression of Aβ major transport proteins P-glycoprotein and LRP1. Collectively, our findings that donepezil and rivastigmine enhance Aβ clearance across the BBB and liver are novel and introduce an additional mechanism by which both drugs could affect AD pathology. Thus, optimizing their clinical use could help future drug development by providing new drug targets and possible mechanisms involved in AD pathology.
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Affiliation(s)
- Loqman A. Mohamed
- Department of Basic Pharmaceutical Science, School of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Dr., Monroe, Louisiana 71201, United States
| | - Hisham Qosa
- Department of Basic Pharmaceutical Science, School of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Dr., Monroe, Louisiana 71201, United States
| | - Amal Kaddoumi
- Department of Basic Pharmaceutical Science, School of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Dr., Monroe, Louisiana 71201, United States
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140
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(-)-Epigallocatechin-3-gallate attenuates cognitive deterioration in Alzheimer's disease model mice by upregulating neprilysin expression. Exp Cell Res 2015; 334:136-45. [PMID: 25882496 DOI: 10.1016/j.yexcr.2015.04.004] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 03/27/2015] [Accepted: 04/05/2015] [Indexed: 01/04/2023]
Abstract
Epigenetic changes are involved in learning and memory, and histone deacetylase (HDAC) inhibitors are considered potential therapeutic agents for Alzheimer's disease (AD). We previously reported that (-)-epigallocatechin-3-gallate (EGCG) acts as an HDAC inhibitor. Here, we demonstrate that EGCG reduced β-amyloid (Aβ) accumulation in vitro and rescued cognitive deterioration in senescence-accelerated mice P8 (SAMP8) via intragastric administration of low- and high-dose EGCG (5 and 15 mg/kg, respectively) for 60 days. The AD brain has decreased levels of the rate-limiting degradation enzyme of Aβ, neprilysin (NEP). We found an association between EGCG-induced reduction in Aβ accumulation and elevated NEP expression. Further, NEP silencing prevented the EGCG-induced Aβ downregulation. Our findings suggest that EGCG might be effective for treating AD.
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141
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Hamilton A, Zamponi GW, Ferguson SSG. Glutamate receptors function as scaffolds for the regulation of β-amyloid and cellular prion protein signaling complexes. Mol Brain 2015; 8:18. [PMID: 25888324 PMCID: PMC4395978 DOI: 10.1186/s13041-015-0107-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 02/27/2015] [Indexed: 01/01/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder that affects 36 million people worldwide, but currently has no effective treatment options. One of the original hallmarks of AD are plaques comprised of beta amyloid (Aβ) and neurofibrillary tangles comprised of phosphorylated Tau protein. However, it is soluble oligomeric Aβ which is more closely correlated with cognitive decline and is therefore considered to be the neurotoxic species. Oligomeric Aβ has recently been shown to form complexes with the glycosylphosphatidylinositol (GPI)-anchored membrane protein, cellular prion protein (PrP(c)), and these complexes are believed to play an important role in the progression of AD pathogenesis. Glutamate, the major excitatory neurotransmitter is responsible for mediating learning and memory under normal physiological conditions. However, the dysregulation of glutamatergic signaling has also been implicated in a number of neurodegenerative diseases including AD. Glutamate acts via both ionotropic glutamate receptors (iGluR) and metabotropic glutamate receptors (mGluR), each of which have been implicated in AD. There is now growing evidence to suggest that mGluR5 may contribute the AD pathogenesis by acting as scaffolds for the PrP(c)/Aβ oligomer complex, enabling the propagation of neurotoxic signaling in AD. In addition, PrP(c) and Aβ oligomer signaling via NMDARs may also contribute to AD pathology. The current review overviews our current understanding of the role of PrP(c) and Aβ oligomers in regulating glutamate receptor signaling, as well as highlights the importance of understanding these signaling complexes to develop more effective therapeutic strategies to treat AD.
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Affiliation(s)
- Alison Hamilton
- J. Allyn Taylor Centre for Cell Biology, Robarts Research Institute, University of Western Ontario, 100 Perth Dr, London, Ontario, N6A 5 K8, Canada.
- Department of Physiology & Pharmacology, University of Western Ontario, London, Ontario, Canada.
| | - Gerald W Zamponi
- Department of Physiology & Pharmacology, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
| | - Stephen S G Ferguson
- J. Allyn Taylor Centre for Cell Biology, Robarts Research Institute, University of Western Ontario, 100 Perth Dr, London, Ontario, N6A 5 K8, Canada.
- Department of Physiology & Pharmacology, University of Western Ontario, London, Ontario, Canada.
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142
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Choi JY, Lee JM, Lee DG, Cho S, Yoon YH, Cho EJ, Lee S. The n-Butanol Fraction and Rutin from Tartary Buckwheat Improve Cognition and Memory in an In Vivo Model of Amyloid-β-Induced Alzheimer's Disease. J Med Food 2015; 18:631-41. [PMID: 25785882 DOI: 10.1089/jmf.2014.3292] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
This study examined the beneficial effects of the n-butanol fraction and rutin extracted from tartary buckwheat (TB) on learning and memory deficits in a mouse model of amyloid β (Aβ)-induced Alzheimer's disease (AD). Learning and memory were assessed using the T-maze, object recognition, and Morris water maze tests. Animals administered Aβ showed impaired cognition and memory, which were alleviated by oral administration of an n-butanol fraction and rutin extracted from TB. Similarly, Aβ-induced increases in nitric oxide formation and lipid peroxidation in the brain, liver, and kidneys were attenuated by treatment with n-butanol fraction and rutin from TB in addition to antioxidant effects observed in control (nonAβ-treated) animals. The results of the present study suggest that the n-butanol fraction and rutin extracted from TB are protective against and have possible therapeutic applications for the treatment of AD.
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Affiliation(s)
- Ji Yeon Choi
- 1Department of Food Science and Nutrition, Research Institute of Ecology for the Elderly, Pusan National University, Busan, Korea
| | - Jeong Min Lee
- 2Department of Integrative Plant Science, Chung-Ang University, Anseong, Korea.,3Department of Functional Crops, National Institute of Crop Science, Rural Development Administration, Miryang, Korea
| | - Dong Gu Lee
- 2Department of Integrative Plant Science, Chung-Ang University, Anseong, Korea
| | - Sunghun Cho
- 2Department of Integrative Plant Science, Chung-Ang University, Anseong, Korea
| | - Young-Ho Yoon
- 3Department of Functional Crops, National Institute of Crop Science, Rural Development Administration, Miryang, Korea
| | - Eun Ju Cho
- 1Department of Food Science and Nutrition, Research Institute of Ecology for the Elderly, Pusan National University, Busan, Korea
| | - Sanghyun Lee
- 2Department of Integrative Plant Science, Chung-Ang University, Anseong, Korea
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143
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Blake MR, Holbrook SD, Kotwica-Rolinska J, Chow ES, Kretzschmar D, Giebultowicz JM. Manipulations of amyloid precursor protein cleavage disrupt the circadian clock in aging Drosophila. Neurobiol Dis 2015; 77:117-26. [PMID: 25766673 DOI: 10.1016/j.nbd.2015.02.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 01/14/2015] [Accepted: 02/15/2015] [Indexed: 11/30/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease characterized by severe cognitive deterioration. While causes of AD pathology are debated, a large body of evidence suggests that increased cleavage of Amyloid Precursor Protein (APP) producing the neurotoxic Amyloid-β (Aβ) peptide plays a fundamental role in AD pathogenesis. One of the detrimental behavioral symptoms commonly associated with AD is the fragmentation of sleep-activity cycles with increased nighttime activity and daytime naps in humans. Sleep-activity cycles, as well as physiological and cellular rhythms, which may be important for neuronal homeostasis, are generated by a molecular system known as the circadian clock. Links between AD and the circadian system are increasingly evident but not well understood. Here we examined whether genetic manipulations of APP-like (APPL) protein cleavage in Drosophila melanogaster affect rest-activity rhythms and core circadian clock function in this model organism. We show that the increased β-cleavage of endogenous APPL by the β-secretase (dBACE) severely disrupts circadian behavior and leads to reduced expression of clock protein PER in central clock neurons of aging flies. Our data suggest that behavioral rhythm disruption is not a product of APPL-derived Aβ production but rather may be caused by a mechanism common to both α and β-cleavage pathways. Specifically, we show that increased production of the endogenous Drosophila Amyloid Intracellular Domain (dAICD) caused disruption of circadian rest-activity rhythms, while flies overexpressing endogenous APPL maintained stronger circadian rhythms during aging. In summary, our study offers a novel entry point toward understanding the mechanism of circadian rhythm disruption in Alzheimer's disease.
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Affiliation(s)
- Matthew R Blake
- Department of Integrative Biology, Oregon State University, Corvallis, OR 97331, USA
| | - Scott D Holbrook
- Oregon Institute of Occupational Health Sciences, Oregon Health and Science University, Portland, OR 97239, USA
| | | | - Eileen S Chow
- Department of Integrative Biology, Oregon State University, Corvallis, OR 97331, USA
| | - Doris Kretzschmar
- Oregon Institute of Occupational Health Sciences, Oregon Health and Science University, Portland, OR 97239, USA
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144
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Ritzel RM, Patel AR, Pan S, Crapser J, Hammond M, Jellison E, McCullough LD. Age- and location-related changes in microglial function. Neurobiol Aging 2015; 36:2153-63. [PMID: 25816747 DOI: 10.1016/j.neurobiolaging.2015.02.016] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Revised: 02/08/2015] [Accepted: 02/13/2015] [Indexed: 11/26/2022]
Abstract
Inflammation in the central nervous system (CNS) is primarily regulated by microglia. No longer considered a homogenous population, microglia display a high degree of heterogeneity, immunological diversity and regional variability in function. Given their low rate of self-renewal, the microenvironment in which microglia reside may play an important role in microglial senescence. This study examines age-related changes in microglia in the brain and spinal cord. Using ex-vivo flow cytometry analyses, functional assays were performed to assess changes in microglial morphology, oxidative stress, cytokine production, and phagocytic activity with age in both the brain and spinal cord. The regional CNS environment had a significant effect on microglial activity with age. Blood-CNS barrier permeability was greater in the aging spinal cord compared with aging brain; this was associated with increased tissue cytokine levels. Aged microglia had deficits in phagocytosis at baseline and after stimulus-induced activation. The identification of age-specific, high scatter microglia together with the use of ex-vivo functional analyses provides the first functional characterization of senescent microglia. Age and regional-specificity of CNS disease should be taken into consideration when developing immune-modulatory treatments.
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Affiliation(s)
- Rodney M Ritzel
- Department of Neurology, University of Connecticut Health Center, Farmington, CT, USA
| | - Anita R Patel
- Department of Neurology, University of Connecticut Health Center, Farmington, CT, USA
| | - Sarah Pan
- Department of Neurology, University of Connecticut Health Center, Farmington, CT, USA
| | - Joshua Crapser
- Department of Neurology, University of Connecticut Health Center, Farmington, CT, USA
| | - Matt Hammond
- Department of Neurology, University of Connecticut Health Center, Farmington, CT, USA
| | - Evan Jellison
- Department of Immunology, University of Connecticut Health Center, Farmington, CT, USA
| | - Louise D McCullough
- Department of Neurology, University of Connecticut Health Center, Farmington, CT, USA.
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145
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Silverberg GD, Miller MC, Pascale CL, Caralopoulos IN, Agca Y, Agca C, Stopa EG. Kaolin-induced chronic hydrocephalus accelerates amyloid deposition and vascular disease in transgenic rats expressing high levels of human APP. Fluids Barriers CNS 2015; 12:2. [PMID: 25685319 PMCID: PMC4328504 DOI: 10.1186/2045-8118-12-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 01/14/2015] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Normal pressure hydrocephalus (NPH) is most common in the elderly and has a high co-morbidity with Alzheimer's disease (AD) and cerebrovascular disease (CVD). To understand the relationship between NPH, AD and CVD, we investigated how chronic hydrocephalus impacts brain amyloid-beta peptide (Aβ) accumulation and vascular pathology in an AD transgenic rodent model. Previously we showed that the altered CSF physiology produced by kaolin-hydrocephalus in older wild-type Sprague-Dawley rats increased Aβ and hyperphosphorylated Tau (Silverberg et. al. Brain Res. 2010, 1317:286-296). We postulated that hydrocephalus would similarly affect an AD rat model. METHODS Thirty-five transgenic rats (tgAPP21) that express high levels of human APP and naturally overproduce Aβ40 were used. Six- (n = 7) and twelve-month-old (n = 9) rats had hydrocephalus induced by cisternal kaolin injection. We analyzed Aβ burden (Aβ40, Aβ42 and oligomeric Aβ) and vascular integrity (Masson trichrome and Verhoeff-Van Gieson) by immunohistochemistry and chemical staining at 10 weeks (n = 8) and 6 months (n = 5) post hydrocephalus induction. We also analyzed whether the vascular pathology seen in tgAPP21 rats, which develop amyloid angiopathy, was accelerated by hydrocephalus. Age-matched naïve and sham-operated tgAPP21 rats served as controls (n = 19). RESULTS In hydrocephalic tgAPP21 rats, compared to naïve and sham-operated controls, there was increased Aβ 40 and oligomeric Aβ in hippocampal and cortical neurons at 10 weeks and 6 months post-hydrocephalus induction. No dense-core amyloid plaques were seen, but diffuse Aβ immunoreactivity was evident in neurons. Vascular pathology was accelerated by the induction of hydrocephalus compared to controls. In the six-month-old rats, subtle degenerative changes were noted in vessel walls at 10 weeks post-kaolin, whereas at six months post-kaolin and in the 12-month-old hydrocephalic rats more pronounced amyloid angiopathic changes were seen, with frequent large areas of infarction noted. CONCLUSIONS Kaolin-hydrocephalus can accelerate intraneuronal Aβ40 accumulation and vascular pathology in tgAPP21 rats. In addition, disrupted CSF production and reduced CSF turnover results in impaired Aβ clearance and accelerated vascular pathology in chronic hydrocephalus. The high co-morbidity seen in NPH, AD and CVD is likely not to be an age-related coincidence, but rather a convergence of pathologies related to diminished CSF clearance.
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Affiliation(s)
- Gerald D Silverberg
- />Department of Neurosurgery, The Warren Alpert Medical School of Brown University and the Aldrich Laboratories at Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 USA
- />Stanford University, 710 Frenchmans Rd, Stanford, CA 94305 USA
| | - Miles C Miller
- />Department of Neurosurgery, The Warren Alpert Medical School of Brown University and the Aldrich Laboratories at Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 USA
| | - Crissey L Pascale
- />Department of Neurosurgery, The Warren Alpert Medical School of Brown University and the Aldrich Laboratories at Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 USA
| | - Ilias N Caralopoulos
- />Department of Neurosurgery, The Warren Alpert Medical School of Brown University and the Aldrich Laboratories at Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 USA
| | - Yuksel Agca
- />Department of Veterinary Pathobiology, University of Missouri College of Veterinary Medicine, Columbia, MO 65211 USA
| | - Cansu Agca
- />Department of Veterinary Pathobiology, University of Missouri College of Veterinary Medicine, Columbia, MO 65211 USA
| | - Edward G Stopa
- />Department of Neurosurgery, The Warren Alpert Medical School of Brown University and the Aldrich Laboratories at Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 USA
- />Department of Pathology (Neuropathology), Warren Alpert Medical School of Brown University and the Aldrich Laboratories at Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 USA
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146
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The Ubiquitin-Proteasome System and Molecular Chaperone Deregulation in Alzheimer's Disease. Mol Neurobiol 2015; 53:905-931. [PMID: 25561438 DOI: 10.1007/s12035-014-9063-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 12/09/2014] [Indexed: 12/18/2022]
Abstract
One of the shared hallmarks of neurodegenerative diseases is the accumulation of misfolded proteins. Therefore, it is suspected that normal proteostasis is crucial for neuronal survival in the brain and that the malfunction of this mechanism may be the underlying cause of neurodegenerative diseases. The accumulation of amyloid plaques (APs) composed of amyloid-beta peptide (Aβ) aggregates and neurofibrillary tangles (NFTs) composed of misfolded Tau proteins are the defining pathological markers of Alzheimer's disease (AD). The accumulation of these proteins indicates a faulty protein quality control in the AD brain. An impaired ubiquitin-proteasome system (UPS) could lead to negative consequences for protein regulation, including loss of function. Another pivotal mechanism for the prevention of misfolded protein accumulation is the utilization of molecular chaperones. Molecular chaperones, such as heat shock proteins (HSPs) and FK506-binding proteins (FKBPs), are highly involved in protein regulation to ensure proper folding and normal function. In this review, we elaborate on the molecular basis of AD pathophysiology using recent data, with a particular focus on the role of the UPS and molecular chaperones as the defensive mechanism against misfolded proteins that have prion-like properties. In addition, we propose a rational therapy approach based on this mechanism.
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147
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Lv G, Cui B, Lan H, Wen Y, Sun A, Yi T. Diarylethene based fluorescent switchable probes for the detection of amyloid-β pathology in Alzheimer's disease. Chem Commun (Camb) 2015; 51:125-8. [DOI: 10.1039/c4cc07656g] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Two fluorescent switchable diarylethene derivatives which can detect amyloid-β aggregates bothin vitroandin vivowere reported.
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Affiliation(s)
- Guanglei Lv
- Department of Chemistry & Innovation Center of Chemistry for Energy Materials
- Fudan University
- Shanghai 200433
- P. R. China
| | - Baiping Cui
- Laboratory of Neurodegenerative Diseases and Repair
- Yancheng Institute of Health Sciences
- Yancheng 224005
- P. R. China
| | - Haichuang Lan
- Department of Chemistry & Innovation Center of Chemistry for Energy Materials
- Fudan University
- Shanghai 200433
- P. R. China
| | - Ying Wen
- Department of Chemistry & Innovation Center of Chemistry for Energy Materials
- Fudan University
- Shanghai 200433
- P. R. China
| | - Anyang Sun
- Laboratory of Neurodegenerative Diseases and Repair
- Yancheng Institute of Health Sciences
- Yancheng 224005
- P. R. China
| | - Tao Yi
- Department of Chemistry & Innovation Center of Chemistry for Energy Materials
- Fudan University
- Shanghai 200433
- P. R. China
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148
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Benseny-Cases N, Klementieva O, Cotte M, Ferrer I, Cladera J. Microspectroscopy (μFTIR) reveals co-localization of lipid oxidation and amyloid plaques in human Alzheimer disease brains. Anal Chem 2014; 86:12047-54. [PMID: 25415602 DOI: 10.1021/ac502667b] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Amyloid peptides are the main component of one of the characteristic pathological hallmarks of Alzheimer's disease (AD): senile plaques. According to the amyloid cascade hypothesis, amyloid peptides may play a central role in the sequence of events that leads to neurodegeneration. However, there are other factors, such as oxidative stress, that may be crucial for the development of the disease. In the present paper, we show that it is possible, by using Fourier tranform infrared (FTIR) microscopy, to co-localize amyloid deposits and lipid peroxidation in tissue slides from patients affected by Alzheimer's disease. Plaques and lipids can be analyzed in the same sample, making use of the characteristic infrared bands for peptide aggregation and lipid oxidation. The results show that, in samples from patients diagnosed with AD, the plaques and their immediate surroundings are always characterized by the presence of oxidized lipids. As for samples from non-AD individuals, those without amyloid plaques show a lower level of lipid oxidation than AD individuals. However, it is known that plaques can be detected in the brains of some non-AD individuals. Our results show that, in such cases, the lipid in the plaques and their surroundings display oxidation levels that are similar to those of tissues with no plaques. These results point to lipid oxidation as a possible key factor in the path that goes from showing the typical neurophatological hallmarks to suffering from dementia. In this process, the oxidative power of the amyloid peptide, possibly in the form of nonfibrillar aggregates, could play a central role.
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Affiliation(s)
- Núria Benseny-Cases
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, F-38000 Grenoble, France
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149
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Combined treatment with a BACE inhibitor and anti-Aβ antibody gantenerumab enhances amyloid reduction in APPLondon mice. J Neurosci 2014; 34:11621-30. [PMID: 25164658 DOI: 10.1523/jneurosci.1405-14.2014] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Therapeutic approaches for prevention or reduction of amyloidosis are currently a main objective in basic and clinical research on Alzheimer's disease. Among the agents explored in clinical trials are anti-Aβ peptide antibodies and secretase inhibitors. Most anti-Aβ antibodies are considered to act via inhibition of amyloidosis and enhanced clearance of existing amyloid, although secretase inhibitors reduce the de novo production of Aβ. Limited information is currently available on the efficacy and potential advantages of combinatorial antiamyloid treatment. We performed a chronic study in APPLondon transgenic mice that received treatment with anti-Aβ antibody gantenerumab and BACE inhibitor RO5508887, either as mono- or combination treatment. Treatment aimed to evaluate efficacy on amyloid progression, similar to preexisting amyloidosis as present in Alzheimer's disease patients. Mono-treatments with either compound caused a dose-dependent reduction of total brain Aβ and amyloid burden. Combination treatment with both compounds significantly enhanced the antiamyloid effect. The observed combination effect was most pronounced for lowering of amyloid plaque load and plaque number, which suggests effective inhibition of de novo plaque formation. Moreover, significantly enhanced clearance of pre-existing amyloid plaques was observed when gantenerumab was coadministered with RO5508887. BACE inhibition led to a significant time- and dose-dependent decrease in CSF Aβ, which was not observed for gantenerumab treatment. Our results demonstrate that combining these two antiamyloid agents enhances overall efficacy and suggests that combination treatments may be of clinical relevance.
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150
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Kinetics of serotonin oxidation by heme–Aβ relevant to Alzheimer’s disease. J Biol Inorg Chem 2014; 19:1355-65. [DOI: 10.1007/s00775-014-1193-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 09/04/2014] [Indexed: 01/11/2023]
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