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Stoner A, Fu L, Nicholson L, Zheng C, Toyonaga T, Spurrier J, Laird W, Cai Z, Strittmatter SM. Neuronal transcriptome, tau and synapse loss in Alzheimer's knock-in mice require prion protein. Alzheimers Res Ther 2023; 15:201. [PMID: 37968719 PMCID: PMC10647125 DOI: 10.1186/s13195-023-01345-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 10/25/2023] [Indexed: 11/17/2023]
Abstract
BACKGROUND Progression of Alzheimer's disease leads to synapse loss, neural network dysfunction and cognitive failure. Accumulation of protein aggregates and brain immune activation have triggering roles in synaptic failure but the neuronal mechanisms underlying synapse loss are unclear. On the neuronal surface, cellular prion protein (PrPC) is known to be a high-affinity binding site for Amyloid-β oligomers (Aβo). However, PrPC's dependence in knock-in AD models for tau accumulation, transcriptomic alterations and imaging biomarkers is unknown. METHODS The necessity of PrPC was examined as a function of age in homozygous AppNL-G-F/hMapt double knock-in mice (DKI). Phenotypes of AppNL-G-F/hMapt mice with a deletion of Prnp expression (DKI; Prnp-/-) were compared with DKI mice with intact Prnp, mice with a targeted deletion of Prnp (Prnp-/-), and mice with intact Prnp (WT). Phenotypes examined included behavioral deficits, synapse loss by PET imaging, synapse loss by immunohistology, tau pathology, gliosis, inflammatory markers, and snRNA-seq transcriptomic profiling. RESULTS By 9 months age, DKI mice showed learning and memory impairment, but DKI; Prnp-/- and Prnp-/- groups were indistinguishable from WT. Synapse loss in DKI brain, measured by [18F]SynVesT-1 SV2A PET or anti-SV2A immunohistology, was prevented by Prnp deletion. Accumulation of Tau phosphorylated at aa 217 and 202/205, C1q tagging of synapses, and dystrophic neurites were all increased in DKI mice but each decreased to WT levels with Prnp deletion. In contrast, astrogliosis, microgliosis and Aβ levels were unchanged between DKI and DKI; Prnp-/- groups. Single-nuclei transcriptomics revealed differential expression in neurons and glia of DKI mice relative to WT. For DKI; Prnp-/- mice, the majority of neuronal genes differentially expressed in DKI mice were no longer significantly altered relative to WT, but most glial DKI-dependent gene expression changes persisted. The DKI-dependent neuronal genes corrected by Prnp deletion associated bioinformatically with synaptic function. Additional genes were uniquely altered only in the Prnp-/- or the DKI; Prnp-/- groups. CONCLUSIONS Thus, PrPC-dependent synapse loss, phospho-tau accumulation and neuronal gene expression in AD mice can be reversed without clearing Aβ plaque or preventing gliotic reaction. This supports targeting the Aβo-PrPC interaction to prevent Aβo-neurotoxicity and pathologic tau accumulation in AD.
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Affiliation(s)
- Austin Stoner
- Departments of Neuroscience and Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Li Fu
- Departments of Neuroscience and Neurology, Yale School of Medicine, New Haven, CT, USA
| | - LaShae Nicholson
- Departments of Neuroscience and Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Chao Zheng
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
| | - Takuya Toyonaga
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
| | - Joshua Spurrier
- Departments of Neuroscience and Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Will Laird
- Departments of Neuroscience and Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Zhengxin Cai
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
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Implications of Oligomeric Amyloid-Beta (oAβ 42) Signaling through α7β2-Nicotinic Acetylcholine Receptors (nAChRs) on Basal Forebrain Cholinergic Neuronal Intrinsic Excitability and Cognitive Decline. J Neurosci 2020; 41:555-575. [PMID: 33239400 DOI: 10.1523/jneurosci.0876-20.2020] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 11/03/2020] [Accepted: 11/15/2020] [Indexed: 01/08/2023] Open
Abstract
Neuronal and network-level hyperexcitability is commonly associated with increased levels of amyloid-β (Aβ) and contribute to cognitive deficits associated with Alzheimer's disease (AD). However, the mechanistic complexity underlying the selective loss of basal forebrain cholinergic neurons (BFCNs), a well-recognized characteristic of AD, remains poorly understood. In this study, we tested the hypothesis that the oligomeric form of amyloid-β (oAβ42), interacting with α7-containing nicotinic acetylcholine receptor (nAChR) subtypes, leads to subnucleus-specific alterations in BFCN excitability and impaired cognition. We used single-channel electrophysiology to show that oAβ42 activates both homomeric α7- and heteromeric α7β2-nAChR subtypes while preferentially enhancing α7β2-nAChR open-dwell times. Organotypic slice cultures were prepared from male and female ChAT-EGFP mice, and current-clamp recordings obtained from BFCNs chronically exposed to pathophysiologically relevant level of oAβ42 showed enhanced neuronal intrinsic excitability and action potential firing rates. These resulted from a reduction in action potential afterhyperpolarization and alterations in the maximal rates of voltage change during spike depolarization and repolarization. These effects were observed in BFCNs from the medial septum diagonal band and horizontal diagonal band, but not the nucleus basalis. Last, aged male and female APP/PS1 transgenic mice, genetically null for the β2 nAChR subunit gene, showed improved spatial reference memory compared with APP/PS1 aged-matched littermates. Combined, these data provide a molecular mechanism supporting a role for α7β2-nAChR in mediating the effects of oAβ42 on excitability of specific populations of cholinergic neurons and provide a framework for understanding the role of α7β2-nAChR in oAβ42-induced cognitive decline.
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Purro SA, Nicoll AJ, Collinge J. Prion Protein as a Toxic Acceptor of Amyloid-β Oligomers. Biol Psychiatry 2018; 83:358-368. [PMID: 29331212 DOI: 10.1016/j.biopsych.2017.11.020] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 11/08/2017] [Accepted: 11/13/2017] [Indexed: 02/08/2023]
Abstract
The initial report that cellular prion protein (PrPC) mediates toxicity of amyloid-β species linked to Alzheimer's disease was initially treated with scepticism, but growing evidence supports this claim. That there is a high-affinity interaction is now clear, and its molecular basis is being unraveled, while recent studies have identified possible downstream toxic mechanisms. Determination of the clinical significance of such interactions between PrPC and disease-associated amyloid-β species will require experimental medicine studies in humans. Trials of compounds that inhibit PrP-dependent amyloid-β toxicity are commencing in humans, and although it is clear that only a fraction of Alzheimer's disease toxicity could be governed by PrPC, a partial, but still therapeutically useful, role in human disease may soon be testable.
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Affiliation(s)
- Silvia A Purro
- Medical Research Council Prion Unit, Institute of Prion Diseases, University College London (UCL), London, United Kingdom
| | - Andrew J Nicoll
- Medical Research Council Prion Unit, Institute of Prion Diseases, University College London (UCL), London, United Kingdom; Elkington and Fife LLP, Kent, United Kingdom.
| | - John Collinge
- Medical Research Council Prion Unit, Institute of Prion Diseases, University College London (UCL), London, United Kingdom.
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Zhao J, Ma B, Nussinov R. Compilation and Analysis of Enzymes, Engineered Antibodies, and Nanoparticles Designed to Interfere with Amyloid-β Aggregation. Isr J Chem 2016. [DOI: 10.1002/ijch.201600093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jun Zhao
- Cancer and Inflammation Program; National Cancer Institute; Frederick Maryland 21702 USA
| | - Buyong Ma
- Basic Science Program; Leidos Biomedical Research, Inc.; Cancer and Inflammation Program; National Cancer Institute; Frederick Maryland 21702 USA
| | - Ruth Nussinov
- Basic Science Program; Leidos Biomedical Research, Inc.; Cancer and Inflammation Program; National Cancer Institute; Frederick Maryland 21702 USA
- Sackler Institute of Molecular Medicine; Department of Human Genetics and Molecular Medicine; Sackler School of Medicine; Tel Aviv University; Tel Aviv 69978 Israel
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5
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Han SH, Park JC, Mook-Jung I. Amyloid β-interacting partners in Alzheimer's disease: From accomplices to possible therapeutic targets. Prog Neurobiol 2016; 137:17-38. [DOI: 10.1016/j.pneurobio.2015.12.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 12/02/2015] [Accepted: 12/09/2015] [Indexed: 12/20/2022]
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Nygaard HB, Wagner AF, Bowen GS, Good SP, MacAvoy MG, Strittmatter KA, Kaufman AC, Rosenberg BJ, Sekine-Konno T, Varma P, Chen K, Koleske AJ, Reiman EM, Strittmatter SM, van Dyck CH. A phase Ib multiple ascending dose study of the safety, tolerability, and central nervous system availability of AZD0530 (saracatinib) in Alzheimer's disease. ALZHEIMERS RESEARCH & THERAPY 2015; 7:35. [PMID: 25874001 PMCID: PMC4396171 DOI: 10.1186/s13195-015-0119-0] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 03/16/2015] [Indexed: 12/31/2022]
Abstract
Introduction Despite significant progress, a disease-modifying therapy for Alzheimer’s disease (AD) has not yet been developed. Recent findings implicate soluble oligomeric amyloid beta as the most relevant protein conformation in AD pathogenesis. We recently described a signaling cascade whereby oligomeric amyloid beta binds to cellular prion protein on the neuronal cell surface, activating intracellular Fyn kinase to mediate synaptotoxicity. Fyn kinase has been implicated in AD pathophysiology both in in vitro models and in human subjects, and is a promising new therapeutic target for AD. Herein, we present a Phase Ib trial of the repurposed investigational drug AZD0530, a Src family kinase inhibitor specific for Fyn and Src kinase, for the treatment of patients with mild-to-moderate AD. Methods The study was a 4-week Phase Ib multiple ascending dose, randomized, double-blind, placebo-controlled trial of AZD0530 in AD patients with Mini-Mental State Examination (MMSE) scores ranging from 16 to 26. A total of 24 subjects were recruited in three sequential groups, with each randomized to receive oral AZD0530 at doses of 50 mg, 100 mg, 125 mg, or placebo daily for 4 weeks. The drug:placebo ratio was 3:1. Primary endpoints were safety, tolerability, and cerebrospinal fluid (CSF) penetration of AZD0530. Secondary endpoints included changes in clinical efficacy measures (Alzheimer’s Disease Assessment Scale – cognitive subscale, MMSE, Alzheimer’s Disease Cooperative Study – Activities of Daily Living Inventory, Neuropsychiatric Inventory, and Clinical Dementia Rating Scale – Sum of Boxes) and regional cerebral glucose metabolism measured by fluorodeoxyglucose positron emission tomography. Results AZD0530 was generally safe and well tolerated across doses. One subject receiving 125 mg of AZD0530 was discontinued from the study due to the development of congestive heart failure and atypical pneumonia, which were considered possibly related to the study drug. Plasma/CSF ratio of AZD0530 was 0.4. The 100 mg and 125 mg doses achieved CSF drug levels corresponding to brain levels that rescued memory deficits in transgenic mouse models. One-month treatment with AZD0530 had no significant effect on clinical efficacy measures or regional cerebral glucose metabolism. Conclusions AZD0530 is reasonably safe and well tolerated in patients with mild-to-moderate AD, achieving substantial central nervous system penetration with oral dosing at 100–125 mg. Targeting Fyn kinase may be a promising therapeutic approach in AD, and a larger Phase IIa clinical trial of AZD0530 for the treatment of patients with AD has recently launched. Trial registration ClinicalTrials.gov: NCT01864655. Registered 12 June 2014.
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Affiliation(s)
- Haakon B Nygaard
- Alzheimer's Disease Research Unit, Yale University School of Medicine, New Haven, Connecticut USA ; Department of Neurology, Yale University School of Medicine, New Haven, Connecticut USA ; Program in Cellular Neuroscience, Neurodegeneration and Repair (CNNR), Yale University School of Medicine, New Haven, Connecticut USA ; Current address: University of British Columbia, Division of Neurology, Djavad Mowafaghian Centre for Brain Health, Vancouver, Canada
| | - Allison F Wagner
- Alzheimer's Disease Research Unit, Yale University School of Medicine, New Haven, Connecticut USA ; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut USA
| | - Garrett S Bowen
- Alzheimer's Disease Research Unit, Yale University School of Medicine, New Haven, Connecticut USA ; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut USA
| | - Susan P Good
- Alzheimer's Disease Research Unit, Yale University School of Medicine, New Haven, Connecticut USA ; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut USA
| | - Martha G MacAvoy
- Alzheimer's Disease Research Unit, Yale University School of Medicine, New Haven, Connecticut USA ; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut USA
| | - Kurt A Strittmatter
- Program in Cellular Neuroscience, Neurodegeneration and Repair (CNNR), Yale University School of Medicine, New Haven, Connecticut USA
| | - Adam C Kaufman
- Program in Cellular Neuroscience, Neurodegeneration and Repair (CNNR), Yale University School of Medicine, New Haven, Connecticut USA
| | - Brian J Rosenberg
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, Connecticut USA
| | - Tomoko Sekine-Konno
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut USA
| | - Pradeep Varma
- Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut USA
| | - Kewei Chen
- Banner Alzheimer's Institute, Phoenix, Arizona USA
| | - Anthony J Koleske
- Program in Cellular Neuroscience, Neurodegeneration and Repair (CNNR), Yale University School of Medicine, New Haven, Connecticut USA ; Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, Connecticut USA
| | | | - Stephen M Strittmatter
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut USA ; Program in Cellular Neuroscience, Neurodegeneration and Repair (CNNR), Yale University School of Medicine, New Haven, Connecticut USA
| | - Christopher H van Dyck
- Alzheimer's Disease Research Unit, Yale University School of Medicine, New Haven, Connecticut USA ; Department of Neurology, Yale University School of Medicine, New Haven, Connecticut USA ; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut USA
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Béland M, Roucou X. Taking advantage of physiological proteolytic processing of the prion protein for a therapeutic perspective in prion and Alzheimer diseases. Prion 2015; 8:106-10. [PMID: 24335160 DOI: 10.4161/pri.27438] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Prion and Alzheimer diseases are fatal neurodegenerative diseases caused by misfolding and aggregation of the cellular prion protein (PrP(C)) and the β-amyloid peptide, respectively. Soluble oligomeric species rather than large aggregates are now believed to be neurotoxic. PrP(C) undergoes three proteolytic cleavages as part of its natural life cycle, α-cleavage, β-cleavage, and ectodomain shedding. Recent evidences demonstrate that the resulting secreted PrP(C) molecules might represent natural inhibitors against soluble toxic species. In this mini-review, we summarize recent observations suggesting the potential benefit of using PrP(C)-derived molecules as therapeutic agents in prion and Alzheimer diseases.
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8
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Gastrodin suppresses the amyloid β-induced increase of spontaneous discharge in the entorhinal cortex of rats. Neural Plast 2014; 2014:320937. [PMID: 25485157 PMCID: PMC4251795 DOI: 10.1155/2014/320937] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 08/31/2014] [Accepted: 09/01/2014] [Indexed: 12/28/2022] Open
Abstract
Accumulated soluble amyloid beta- (Aβ-) induced aberrant neuronal network activity may directly contribute to cognitive deficits, which are the most outstanding characteristics of Alzheimer's disease (AD). The entorhinal cortex (EC) is one of the earliest affected brain regions in AD. Impairments of EC neurons are responsible for the cognitive deficits in AD. However, little effort has been made to investigate the effects of soluble Aβ on the discharge properties of EC neurons in vivo. The present study was designed to examine the effects of soluble Aβ1−42 on the discharge properties of EC neurons, using in vivo extracellular single unit recordings. The protective effects of gastrodin (GAS) were also investigated against Aβ1−42-induced alterations in EC neuronal activities. The results showed that the spontaneous discharge of EC neurons was increased by local application of soluble Aβ1−42 and that GAS can effectively reverse Aβ1−42-induced facilitation of spontaneous discharge in a concentration-dependent manner. Moreover, whole-cell patch clamp results indicated that the protective function of GAS on abnormal hyperexcitability may be partially mediated by its inhibitory action on Aβ1−42-elicited inward currents in EC neurons. Our study suggested that GAS may provide neuroprotective effects on Aβ1−42-induced hyperactivity in EC neurons of rats.
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9
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Aβ induces its own prion protein N-terminal fragment (PrPN1)–mediated neutralization in amorphous aggregates. Neurobiol Aging 2014; 35:1537-48. [DOI: 10.1016/j.neurobiolaging.2014.02.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 01/31/2014] [Accepted: 02/01/2014] [Indexed: 01/24/2023]
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10
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Hirsch TZ, Hernandez-Rapp J, Martin-Lannerée S, Launay JM, Mouillet-Richard S. PrP(C) signalling in neurons: from basics to clinical challenges. Biochimie 2014; 104:2-11. [PMID: 24952348 DOI: 10.1016/j.biochi.2014.06.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 06/10/2014] [Indexed: 01/05/2023]
Abstract
The cellular prion protein PrP(C) was identified over twenty-five years ago as the normal counterpart of the scrapie prion protein PrP(Sc), itself the main if not the sole component of the infectious agent at the root of Transmissible Spongiform Encephalopathies (TSEs). PrP(C) is a ubiquitous cell surface protein, abundantly expressed in neurons, which constitute the targets of PrP(Sc)-mediated toxicity. Converging evidence have highlighted that neuronal, GPI-anchored PrP(C) is absolutely required for prion-induced neuropathogenesis, which warrants investigating into the normal function exerted by PrP(C) in a neuronal context. It is now well-established that PrP(C) can serve as a cell signalling molecule, able to mobilize transduction cascades in response to interactions with partners. This function endows PrP(C) with the capacity to participate in multiple neuronal processes, ranging from survival to synaptic plasticity. A diverse array of data have allowed to shed light on how this function is corrupted by PrP(Sc). Recently, amyloid Aβ oligomers, whose accumulation is associated with Alzheimer's disease (AD), were shown to similarly instigate toxic events by deviating PrP(C)-mediated signalling. Here, we provide an overview of the various signal transduction cascades ascribed to PrP(C) in neurons, summarize how their subversion by PrP(Sc) or Aβ oligomers contributes to TSE or AD neuropathogenesis and discuss the ensuing clinical implications.
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Affiliation(s)
- Théo Z Hirsch
- INSERM UMR-S1124, 75006 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124, 75006 Paris, France
| | - Julia Hernandez-Rapp
- INSERM UMR-S1124, 75006 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124, 75006 Paris, France; Université Paris Sud 11, ED419 Biosigne, 91400 Orsay, France
| | - Séverine Martin-Lannerée
- INSERM UMR-S1124, 75006 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124, 75006 Paris, France
| | - Jean-Marie Launay
- AP-HP Service de Biochimie, Fondation FondaMental, INSERM U942 Hôpital Lariboisière, 75010 Paris, France; Pharma Research Department, F. Hoffmann-La-Roche Ltd., CH-4070 Basel, Switzerland
| | - Sophie Mouillet-Richard
- INSERM UMR-S1124, 75006 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124, 75006 Paris, France.
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Nicoll AJ, Panico S, Freir DB, Wright D, Terry C, Risse E, Herron CE, O'Malley T, Wadsworth JDF, Farrow MA, Walsh DM, Saibil HR, Collinge J. Amyloid-β nanotubes are associated with prion protein-dependent synaptotoxicity. Nat Commun 2014; 4:2416. [PMID: 24022506 PMCID: PMC3908552 DOI: 10.1038/ncomms3416] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 08/07/2013] [Indexed: 12/21/2022] Open
Abstract
Growing evidence suggests water-soluble, non-fibrillar forms of amyloid-β protein (Aβ) have important roles in Alzheimer’s disease with toxicities mimicked by synthetic Aβ1–42. However, no defined toxic structures acting via specific receptors have been identified and roles of proposed receptors, such as prion protein (PrP), remain controversial. Here we quantify binding to PrP of Aβ1–42 after different durations of aggregation. We show PrP-binding and PrP-dependent inhibition of long-term potentiation (LTP) correlate with the presence of protofibrils. Globular oligomers bind less avidly to PrP and do not inhibit LTP, whereas fibrils inhibit LTP in a PrP-independent manner. That only certain transient Aβ assemblies cause PrP-dependent toxicity explains conflicting reports regarding the involvement of PrP in Aβ-induced impairments. We show that these protofibrils contain a defined nanotubular structure with a previously unidentified triple helical conformation. Blocking the formation of Aβ nanotubes or their interaction with PrP might have a role in treatment of Alzheimer’s disease. Prion protein has been suggested to bind toxic amyloid-ß oligomers. Nicoll et al. demonstrate that binding to prion protein and prion protein-dependent synaptotoxicity correlate with the presence of a tubular form of amyloid-ß with a defined triple helical structure.
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Affiliation(s)
- Andrew J Nicoll
- Medical Research Council Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
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12
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Schmidt C, Becker H, Peter C, Lange K, Friede T, Zerr I. Plasma prion protein concentration and progression of Alzheimer disease. Prion 2014; 8:27964. [PMID: 24549099 DOI: 10.4161/pri.27964] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND/OBJECTIVE Recently, PrP(c) has been linked to AD pathogenesis. Second, a relation of PrP(c) plasma levels with cognitive status and decline of healthy elderly subjects has been reported. Therefore, we hypothesized baseline plasma levels of PrP(c) to be associated with AD progression in cognitive and functional domains. MATERIALS AND METHODS AD patients (n = 84) were included into an observational study at time of diagnosis. Baseline plasma PrP(c) levels were determined. Decline was assessed annually (mean follow-up time 3 years) with the aid of different standardized tests (MMSE, iADL, bADL, GDS, UPDRSIII). Multiple regression analyses were used to uncover potential associations between decline and PrP(c) levels. RESULTS No association of PrP(c) and decline could be established. Presence of diabetes mellitus was linked to slower deterioration. Intake of neuroleptic drugs or memantine was associated with faster progression. CONCLUSION Plasma PrP(c) at baseline could not be shown to be related to AD progression in this study. An interesting association of diabetes mellitus and decline warrants further investigation.
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Affiliation(s)
- Christian Schmidt
- Clinical Dementia Center; Department of Neurology; Georg-August-University Medical Center; Goettingen, Germany
| | - Harry Becker
- Clinical Dementia Center; Department of Neurology; Georg-August-University Medical Center; Goettingen, Germany
| | - Christoph Peter
- Clinical Dementia Center; Department of Neurology; Georg-August-University Medical Center; Goettingen, Germany
| | - Katharina Lange
- Department of Statistics and Bioinformatics; Georg-August-University; Goettingen, Germany
| | - Tim Friede
- Department of Statistics and Bioinformatics; Georg-August-University; Goettingen, Germany
| | - Inga Zerr
- Clinical Dementia Center; Department of Neurology; Georg-August-University Medical Center; Goettingen, Germany
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13
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Nygaard HB, van Dyck CH, Strittmatter SM. Fyn kinase inhibition as a novel therapy for Alzheimer's disease. ALZHEIMERS RESEARCH & THERAPY 2014; 6:8. [PMID: 24495408 PMCID: PMC3978417 DOI: 10.1186/alzrt238] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Alzheimer’s disease (AD) is a devastating neurodegenerative disorder, afflicting more than one-third of people over the age of 85. While many therapies for AD are in late-stage clinical testing, rational drug design based on distinct signaling pathways in this disorder is only now emerging. Here we review the putative signaling pathway of amyloid-beta (Aβ), by which the tyrosine kinase Fyn is activated via cell surface binding of Aβ oligomers to cellular prion protein. Several lines of evidence implicate Fyn in the pathogenesis of AD, and its interaction with both Aβ and Tau renders Fyn a unique therapeutic target that addresses both of the major pathologic hallmarks of AD. We are currently enrolling patients in a phase Ib study of saracatinib (AZD0530), a small molecule inhibitor with high potency for Src and Fyn, for the treatment of AD. The results of this trial and a planned phase IIa multisite study will provide important data regarding the potential for this therapeutic strategy in AD.
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Affiliation(s)
- Haakon B Nygaard
- Department of Neurology, Yale University School of Medicine, PO Box 208018, New Haven, CT 06520, USA ; Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, 295 Congress Avenue, BCMM 436, New Haven, CT 06536, USA
| | - Christopher H van Dyck
- Alzheimer's Disease Research Unit, Yale University School of Medicine, 1 Church Street, Suite 600, New Haven, CT 06510, USA ; Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT 06511, USA
| | - Stephen M Strittmatter
- Department of Neurology, Yale University School of Medicine, PO Box 208018, New Haven, CT 06520, USA ; Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, 295 Congress Avenue, BCMM 436, New Haven, CT 06536, USA
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14
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Yao T, Jiang T, Pan D, Xu ZX, Zhou P. Effect of Al(iii) and curcumin on silk fibroin conformation and aggregation morphology. RSC Adv 2014. [DOI: 10.1039/c4ra04712e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Al(iii) can accelerate the conformation transition of silk fibroin from random coils into β-sheets, and curcumin can reverse the transition.
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Affiliation(s)
- Ting Yao
- State Key Laboratory of Molecular Engineering of Polymers
- Department of Macromolecular Science
- Fudan University
- Shanghai 200433, China
| | - Teng Jiang
- State Key Laboratory of Molecular Engineering of Polymers
- Department of Macromolecular Science
- Fudan University
- Shanghai 200433, China
| | - Deng Pan
- State Key Laboratory of Molecular Engineering of Polymers
- Department of Macromolecular Science
- Fudan University
- Shanghai 200433, China
| | - Zhi-Xue Xu
- State Key Laboratory of Molecular Engineering of Polymers
- Department of Macromolecular Science
- Fudan University
- Shanghai 200433, China
| | - Ping Zhou
- State Key Laboratory of Molecular Engineering of Polymers
- Department of Macromolecular Science
- Fudan University
- Shanghai 200433, China
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Mercer RCC, Ma L, Watts JC, Strome R, Wohlgemuth S, Yang J, Cashman NR, Coulthart MB, Schmitt-Ulms G, Jhamandas JH, Westaway D. The prion protein modulates A-type K+ currents mediated by Kv4.2 complexes through dipeptidyl aminopeptidase-like protein 6. J Biol Chem 2013; 288:37241-55. [PMID: 24225951 DOI: 10.1074/jbc.m113.488650] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Widely expressed in the adult central nervous system, the cellular prion protein (PrP(C)) is implicated in a variety of processes, including neuronal excitability. Dipeptidyl aminopeptidase-like protein 6 (DPP6) was first identified as a PrP(C) interactor using in vivo formaldehyde cross-linking of wild type (WT) mouse brain. This finding was confirmed in three cell lines and, because DPP6 directs the functional assembly of K(+) channels, we assessed the impact of WT and mutant PrP(C) upon Kv4.2-based cell surface macromolecular complexes. Whereas a Gerstmann-Sträussler-Scheinker disease version of PrP with eight extra octarepeats was a loss of function both for complex formation and for modulation of Kv4.2 channels, WT PrP(C), in a DPP6-dependent manner, modulated Kv4.2 channel properties, causing an increase in peak amplitude, a rightward shift of the voltage-dependent steady-state inactivation curve, a slower inactivation, and a faster recovery from steady-state inactivation. Thus, the net impact of wt PrP(C) was one of enhancement, which plays a critical role in the down-regulation of neuronal membrane excitability and is associated with a decreased susceptibility to seizures. Insofar as previous work has established a requirement for WT PrP(C) in the Aβ-dependent modulation of excitability in cholinergic basal forebrain neurons, our findings implicate PrP(C) regulation of Kv4.2 channels as a mechanism contributing to the effects of oligomeric Aβ upon neuronal excitability and viability.
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Buskila Y, Crowe SE, Ellis-Davies GCR. Synaptic deficits in layer 5 neurons precede overt structural decay in 5xFAD mice. Neuroscience 2013; 254:152-9. [PMID: 24055684 DOI: 10.1016/j.neuroscience.2013.09.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 08/20/2013] [Accepted: 09/06/2013] [Indexed: 12/15/2022]
Abstract
Synaptic decay and neurodegeneration are hallmarks of Alzheimer's disease that are thought to precede dementia. Recently, we have reported that the first signs of neuritic dystrophy in a new transgenic mouse model of familial Alzheimer's disease (FAD) called the "5xFAD" are axonal dystrophy followed by loss of spines on basal dendrites. The 5xFAD mouse has profound loss of layer 5 neurons by 12months, and these initial structural insults appear between 4 and 6months of age. Here, we test, for the first time, if synaptic failure of layer 5 neurons in the 5xFAD mouse precedes these structural changes. We used longitudinal, in vivo two-photon fluorescence imaging of bigenic 5xFAD/YFP mice to assess the overall structural stability of layer 5 neurons in young mice (age less than 14weeks). We found these neurons to be structurally and morphologically sound. In parallel, we used in vitro, whole-cell patch clamp electrophysiology of layer 5 pyramidal neurons, from mice aged 8-12weeks, to reveal significant pre- and postsynaptic defects in these cells. Thus our data suggest that layer 5 neurons in the 5xFAD mouse model have synaptic deficits at an early time point, before any overt structural dystrophy, and that such synaptic failure, with co-temporal biochemical changes, may be an early step in neuronal loss.
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Affiliation(s)
- Y Buskila
- Department of Neuroscience, Mount Sinai School of Medicine, New York, NY 10029, USA; Bioelectronics and Neuroscience Group, The MARCS Institute, University of Western Sydney, NSW 2560, Australia
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17
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Wärmländer S, Tiiman A, Abelein A, Luo J, Jarvet J, Söderberg KL, Danielsson J, Gräslund A. Biophysical studies of the amyloid β-peptide: interactions with metal ions and small molecules. Chembiochem 2013; 14:1692-704. [PMID: 23983094 DOI: 10.1002/cbic.201300262] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Indexed: 11/11/2022]
Abstract
Alzheimer's disease is the most common of the protein misfolding ("amyloid") diseases. The deposits in the brains of afflicted patients contain as a major fraction an aggregated insoluble form of the so-called amyloid β-peptides (Aβ peptides): fragments of the amyloid precursor protein of 39-43 residues in length. This review focuses on biophysical studies of the Aβ peptides: that is, of the aggregation pathways and intermediates observed during aggregation, of the molecular structures observed along these pathways, and of the interactions of Aβ with Cu and Zn ions and with small molecules that modify the aggregation pathways. Particular emphasis is placed on studies based on high-resolution and solid-state NMR methods. Theoretical studies relating to the interactions are also included. An emerging picture is that of Aβ peptides in aqueous solution undergoing hydrophobic collapse together with identical partners. There then follows a relatively slow process leading to more ordered secondary and tertiary (quaternary) structures in the growing aggregates. These aggregates eventually assemble into elongated fibrils visible by electron microscopy. Small molecules or metal ions that interfere with the aggregation processes give rise to a variety of aggregation products that may be studied in vitro and considered in relation to observations in cell cultures or in vivo. Although the heterogeneous nature of the processes makes detailed structural studies difficult, knowledge and understanding of the underlying physical chemistry might provide a basis for future therapeutic strategies against the disease. A final part of the review deals with the interactions that may occur between the Aβ peptides and the prion protein, where the latter is involved in other protein misfolding diseases.
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Affiliation(s)
- Sebastian Wärmländer
- Department of Biochemistry and Biophysics, The Arrhenius Laboratories, Stockholm University, 106 91 Stockholm (Sweden)
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Wang H, Ren CH, Gunawardana CG, Schmitt-Ulms G. Overcoming barriers and thresholds - signaling of oligomeric Aβ through the prion protein to Fyn. Mol Neurodegener 2013; 8:24. [PMID: 23856335 PMCID: PMC3722066 DOI: 10.1186/1750-1326-8-24] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 07/09/2013] [Indexed: 12/20/2022] Open
Abstract
Evidence has been mounting for an involvement of the prion protein (PrP) in a molecular pathway assumed to play a critical role in the etiology of Alzheimer disease. A currently popular model sees oligomeric amyloid β (oAβ) peptides bind directly to PrP to emanate a signal that causes activation of the cytoplasmic tyrosine kinase Fyn, an essential player in a cascade of events that ultimately leads to NMDA receptor-mediated excitotoxicity and hyper-phosphorylation of tau. The model does not reveal, however, how extracellular binding of oAβ to PrP is communicated across the plasma membrane barrier to affect activation of Fyn. A scenario whereby PrP may adapt a transmembrane topology to affect Fyn activation in the absence of additional partners is currently not supported by evidence. A survey of known candidate PrP interactors leads to a small number of molecules that are known to acquire a transmembrane topology and understood to contribute to Fyn activation. Because multiple signaling pathways converge onto Fyn, a realistic model needs to take into account a reality of Fyn acting as a hub that integrates signals from multiple inhibitory and activating effectors. To clarify the role of PrP in oAβ-dependent excitotoxicity, future studies may need to incorporate experimental designs that can probe the contributions of Fyn modulator pathways and rely on analogous readouts, rather than threshold effects, known to underlie excitotoxic signaling.
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Affiliation(s)
- Hansen Wang
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Tanz Neuroscience Building, 6 Queen's Park Crescent West, Toronto, Ontario M5S 3H2, Canada
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Kretzschmar H, Tatzelt J. Prion disease: a tale of folds and strains. Brain Pathol 2013; 23:321-32. [PMID: 23587138 PMCID: PMC8029118 DOI: 10.1111/bpa.12045] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 02/04/2013] [Indexed: 12/31/2022] Open
Abstract
Research on prions, the infectious agents of devastating neurological diseases in humans and animals, has been in the forefront of developing the concept of protein aggregation diseases. Prion diseases are distinguished from other neurodegenerative diseases by three peculiarities. First, prion diseases, in addition to being sporadic or genetic like all other neurodegenerative diseases, are infectious diseases. Animal models were developed early on (a long time before the advent of transgenic technology), and this has made possible the discovery of the prion protein as the infectious agent. Second, human prion diseases have true equivalents in animals, such as scrapie, which has been the subject of experimental research for many years. Variant Creutzfeldt-Jakob disease (vCJD) is a zoonosis caused by bovine spongiform encephalopathy (BSE) prions. Third, they show a wide variety of phenotypes in humans and animals, much wider than the variants of any other sporadic or genetic neurodegenerative disease. It has now become firmly established that particular PrP(Sc) isoforms are closely related to specific human prion strains. The variety of human prion diseases, still an enigma in its own right, is a focus of this article. Recently, a series of experiments has shown that the concept of aberrant protein folding and templating, first developed for prions, may apply to a variety of neurodegenerative diseases. In the wake of these discoveries, the term prion has come to be used for Aβ, α-synuclein, tau and possibly others. The self-propagation of alternative conformations seems to be the common denominator of these "prions," which in future, in order to avoid confusion, may have to be specified either as "neurodegenerative prions" or "infectious prions."
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Affiliation(s)
| | - Jörg Tatzelt
- NeurobiochemistryAdolf‐Butenandt‐InstituteLudwig‐Maximilians‐University MunichMunichGermany
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
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20
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Fleisch VC, Leighton PLA, Wang H, Pillay LM, Ritzel RG, Bhinder G, Roy B, Tierney KB, Ali DW, Waskiewicz AJ, Allison WT. Targeted mutation of the gene encoding prion protein in zebrafish reveals a conserved role in neuron excitability. Neurobiol Dis 2013; 55:11-25. [PMID: 23523635 DOI: 10.1016/j.nbd.2013.03.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 02/08/2013] [Accepted: 03/13/2013] [Indexed: 01/09/2023] Open
Abstract
The function of the cellular prion protein (PrP(C)) in healthy brains remains poorly understood, in part because Prnp knockout mice are viable. On the other hand, transient knockdown of Prnp homologs in zebrafish (including two paralogs, prp1 and prp2) has suggested that PrP(C) is required for CNS development, cell adhesion, and neuroprotection. It has been argued that zebrafish Prp2 is most similar to mammalian PrP(C), yet it has remained intransigent to the most thorough confirmations of reagent specificity during knockdown. Thus we investigated the role of prp2 using targeted gene disruption via zinc finger nucleases. Prp2(-/-) zebrafish were viable and did not display overt developmental phenotypes. Back-crossing female prp2(-/-) fish ruled out a role for maternal mRNA contributions. Prp2(-/-) larvae were found to have increased seizure-like behavior following exposure to the convulsant pentylenetetrazol (PTZ), as compared to wild type fish. In situ recordings from intact hindbrains demonstrated that prp2 regulates closing of N-Methyl-d-aspartate (NMDA) receptors, concomitant with neuroprotection during glutamate excitotoxicity. Overall, the knockout of Prp2 function in zebrafish independently confirmed hypothesized roles for PrP, identifying deeply conserved functions in post-developmental regulation of neuron excitability that are consequential to the etiology of prion and Alzheimer diseases.
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Affiliation(s)
- Valerie C Fleisch
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
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21
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Altmeppen HC, Prox J, Puig B, Dohler F, Falker C, Krasemann S, Glatzel M. Roles of endoproteolytic α-cleavage and shedding of the prion protein in neurodegeneration. FEBS J 2013; 280:4338-47. [DOI: 10.1111/febs.12196] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 01/25/2013] [Accepted: 02/14/2013] [Indexed: 12/11/2022]
Affiliation(s)
- Hermann C. Altmeppen
- Institute of Neuropathology; University Medical Center HH-Eppendorf; Hamburg Germany
| | - Johannes Prox
- Institute of Biochemistry; Christian Albrechts University; Kiel Germany
| | - Berta Puig
- Institute of Neuropathology; University Medical Center HH-Eppendorf; Hamburg Germany
| | - Frank Dohler
- Institute of Neuropathology; University Medical Center HH-Eppendorf; Hamburg Germany
| | - Clemens Falker
- Institute of Neuropathology; University Medical Center HH-Eppendorf; Hamburg Germany
| | - Susanne Krasemann
- Institute of Neuropathology; University Medical Center HH-Eppendorf; Hamburg Germany
| | - Markus Glatzel
- Institute of Neuropathology; University Medical Center HH-Eppendorf; Hamburg Germany
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22
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Schmidt C, Artjomova S, Hoeschel M, Zerr I. CSF prion protein concentration and cognition in patients with Alzheimer disease. Prion 2013; 7:229-34. [PMID: 23406922 DOI: 10.4161/pri.23904] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND/OBJECTIVE PrP (c) has been suggested to play a role in AD pathophysiology. CSF concentrations of PrP (c) have been shown to be reduced in AD compared with healthy controls. Furthermore, serum levels of PrP (c) have recently been reported to be associated with the cognitive status of healthy elderly subjects. Therefore, we hypothesized that CSF levels of PrP (c) could be associated with cognitive function of AD patients at the time of diagnosis. METHODS AD patients (n = 114) included into an observational study underwent CERAD testing and lumbar puncture at time of diagnosis / study inclusion. CSF PrP (c) was determined. Generalized linear models were fitted to assess the associations of PrP (c) plus a variety of possible confounding factors and CERAD subscale measures. RESULTS No association of CSF PrP (c) and cognitive status could be established, while other factors (i.e., use of antipsychotic drugs, use of anti-dementia drugs, female sex, pre-progression time) were related to worse cognitive function in some domains. CONCLUSION CSF PrP (c) appears not to be a useful biochemical surrogate of cognitive status in AD at the time of diagnosis. Follow-up analyses will examine possible associations with the speed of cognitive decline.
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Affiliation(s)
- Christian Schmidt
- Clinical Dementia Center, Department of Neurology, Georg-August-University, Goettingen, Germany.
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23
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Resenberger UK, Müller V, Munter LM, Baier M, Multhaup G, Wilson MR, Winklhofer KF, Tatzelt J. The heat shock response is modulated by and interferes with toxic effects of scrapie prion protein and amyloid β. J Biol Chem 2012; 287:43765-76. [PMID: 23115236 PMCID: PMC3527961 DOI: 10.1074/jbc.m112.389007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 10/27/2012] [Indexed: 12/19/2022] Open
Abstract
The heat shock response (HSR) is an evolutionarily conserved pathway designed to maintain proteostasis and to ameliorate toxic effects of aberrant protein folding. We have studied the modulation of the HSR by the scrapie prion protein (PrP(Sc)) and amyloid β peptide (Aβ) and investigated whether an activated HSR or the ectopic expression of individual chaperones can interfere with PrP(Sc)- or Aβ-induced toxicity. First, we observed different effects on the HSR under acute or chronic exposure of cells to PrP(Sc) or Aβ. In chronically exposed cells the threshold to mount a stress response was significantly increased, evidenced by a decreased expression of Hsp72 after stress, whereas an acute exposure lowered the threshold for stress-induced expression of Hsp72. Next, we employed models of PrP(Sc)- and Aβ-induced toxicity to demonstrate that the induction of the HSR ameliorates the toxic effects of both PrP(Sc) and Aβ. Similarly, the ectopic expression of cytosolic Hsp72 or the extracellular chaperone clusterin protected against PrP(Sc)- or Aβ-induced toxicity. However, toxic signaling induced by a pathogenic PrP mutant located at the plasma membrane was prevented by an activated HSR or Hsp72 but not by clusterin, indicating a distinct mode of action of this extracellular chaperone. Our study supports the notion that different pathological protein conformers mediate toxic effects via similar cellular pathways and emphasizes the possibility to exploit the heat shock response therapeutically.
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Affiliation(s)
- Ulrike K. Resenberger
- From the Neurobiochemistry, Adolf-Butenandt-Institute, Ludwig-Maximilians-University Munich, D-80336 Munich, Germany
| | - Veronika Müller
- From the Neurobiochemistry, Adolf-Butenandt-Institute, Ludwig-Maximilians-University Munich, D-80336 Munich, Germany
| | - Lisa M. Munter
- Institut für Chemie und Biochemie, Freie Universität, 14195 Berlin, Germany
- the Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec H3A0G4, Canada
| | | | - Gerd Multhaup
- Institut für Chemie und Biochemie, Freie Universität, 14195 Berlin, Germany
- the Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec H3A0G4, Canada
| | - Mark R. Wilson
- the School of Biological Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia, and
| | - Konstanze F. Winklhofer
- From the Neurobiochemistry, Adolf-Butenandt-Institute, Ludwig-Maximilians-University Munich, D-80336 Munich, Germany
- the German Center for Neurodegenerative Diseases (DZNE), 80336 Munich, Germany
| | - Jörg Tatzelt
- From the Neurobiochemistry, Adolf-Butenandt-Institute, Ludwig-Maximilians-University Munich, D-80336 Munich, Germany
- the German Center for Neurodegenerative Diseases (DZNE), 80336 Munich, Germany
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24
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Kaiser DM, Acharya M, Leighton PLA, Wang H, Daude N, Wohlgemuth S, Shi B, Allison WT. Amyloid beta precursor protein and prion protein have a conserved interaction affecting cell adhesion and CNS development. PLoS One 2012; 7:e51305. [PMID: 23236467 PMCID: PMC3517466 DOI: 10.1371/journal.pone.0051305] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 10/31/2012] [Indexed: 01/12/2023] Open
Abstract
Genetic and biochemical mechanisms linking onset or progression of Alzheimer Disease and prion diseases have been lacking and/or controversial, and their etiologies are often considered independent. Here we document a novel, conserved and specific genetic interaction between the proteins that underlie these diseases, amyloid-β precursor protein and prion protein, APP and PRP, respectively. Knockdown of APP and/or PRNP homologs in the zebrafish (appa, appb, prp1, and prp2) produces a dose-dependent phenotype characterized by systemic morphological defects, reduced cell adhesion and CNS cell death. This genetic interaction is surprisingly exclusive in that prp1 genetically interacts with zebrafish appa, but not with appb, and the zebrafish paralog prp2 fails to interact with appa. Intriguingly, appa & appb are largely redundant in early zebrafish development yet their abilities to rescue CNS cell death are differentially contingent on prp1 abundance. Delivery of human APP or mouse Prnp mRNAs rescue the phenotypes observed in app-prp-depleted zebrafish, highlighting the conserved nature of this interaction. Immunoprecipitation revealed that human APP and PrP(C) proteins can have a physical interaction. Our study reports a unique in vivo interdependence between APP and PRP loss-of-function, detailing a biochemical interaction that considerably expands the hypothesized roles of PRP in Alzheimer Disease.
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Affiliation(s)
- Darcy M. Kaiser
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Moulinath Acharya
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Patricia L. A. Leighton
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Hao Wang
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Nathalie Daude
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Serene Wohlgemuth
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Beipei Shi
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - W. Ted Allison
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Department of Medical Genetics, University of Alberta, Edmonton, Alberta, Canada
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25
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Abstract
Prion disease research has opened up the "black-box" of neurodegeneration, defining a key role for protein misfolding wherein a predominantly alpha-helical precursor protein, PrP (C), is converted to a disease-associated, β-sheet enriched isoform called PrP (Sc). In Alzheimer disease (AD) the Aβ peptide derived from the β-amyloid precuror protein APP folds in β-sheet amyloid. Early thoughts along the lines of overlap may have been on target, (1) but were eclipsed by a simultaneous (but now anachronistic) controversy over the role of PrP (Sc) in prion diseases. (2) (,) (3) Nonetheless, as prion diseases such as Creutzfeldt-Jakob Disease (CJD) are themselves rare and can include an overt infectious mode of transmission, and as familial prion diseases and familial AD involve different genes, an observer might reasonably have concluded that prion research could occasionally catalyze ideas in AD, but could never provide concrete overlaps at the mechanistic level. Surprisingly, albeit a decade or three down the road, several prion/AD commonalities can be found within the contemporary literature. One important prion/AD overlap concerns seeded spread of Aβ aggregates by intracerebral inoculation much like prions, (4) and, with a neuron-to-neuron 'spreading' also reported for pathologic forms of other misfolded proteins, Tau (5) (,) (6) and α-synuclein in the case of Parkinson Disease. (7) (,) (8) The concept of seeded spread has been discussed extensively elsewhere, sometimes under the rubric of "prionoids" (9), and lies outside the scope of this particular review where we will focus upon PrP (C). From this point the story can now be subdivided into four strands of investigation: (1) pathologic effects of Aβ can be mediated by binding to PrP (C), (10) (2) the positioning of endoproteolytic processing events of APP by pathologic (β-cleavage + γ-cleavage) and non-pathologic (α-cleavage + γ-cleavage) secretase pathways is paralleled by seemingly analogous α- and β-like cleavage of PrP (C) (Fig. 1) (3) similar lipid raft environments for PrP (C) and APP processing machinery, (11) (-) (13) and perhaps in consequence, overlaps in repertoire of the PrP (C) and APP protein interactors ("interactomes"), (14) (,) (15) and (4) rare kindreds with mixed AD and prion pathologies. (16) Here we discuss confounds, consensus and conflict associated with parameters that apply to these experimental settings.
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Affiliation(s)
- David Westaway
- Department of Medicine (Neurology); University of Alberta; Edmonton, AB Canada
- Centre for Prions and Protein Folding Diseases; University of Alberta; Edmonton, AB Canada
- Department of Biochemistry; University of Alberta; Edmonton, AB Canada
| | - Jack H. Jhamandas
- Department of Medicine (Neurology); University of Alberta; Edmonton, AB Canada
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26
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Breitling LP, Müller H, Stegmaier C, Kliegel M, Brenner H. Association of prion protein with cognitive functioning in humans. Exp Gerontol 2012; 47:919-24. [PMID: 22967749 DOI: 10.1016/j.exger.2012.08.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2012] [Revised: 07/05/2012] [Accepted: 08/03/2012] [Indexed: 01/16/2023]
Abstract
OBJECTIVES Recent animal studies have suggested a key role for cellular prion protein (PrPc) in the pathological consequences of amyloid plaque formation, the hallmark of Alzheimer's disease. This epidemiological study investigated whether serum concentrations of PrPc are associated with cognitive functioning in humans. DESIGN, SETTING, PARTICIPANTS Cross-sectional study of 1,322 participants from the elderly general population in Germany, aged 65+ years at baseline (2000-2002). MEASUREMENTS Cognitive functioning was assessed by the COGTEL phone interview 5years after baseline. Serum PrPc was determined by a commercial immunoassay. RESULTS In multiple linear regression adjusted for important confounders, subjects in higher PrPc quintiles appeared to have lower cognitive functioning scores than those in the lowest PrPc quintile. Spline regression suggested pronounced non-linearity with an inverse association between PrPc and cognitive functioning levelling off beyond median PrPc. Cognitive subdomain-specific models produced somewhat heterogeneous results. CONCLUSION The findings are suggestive of an independent association of PrPc with cognitive functioning in humans. Confirmatory and longitudinal studies are needed to elucidate the potential of PrPc for applications in early risk stratification for cognitive impairment.
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Affiliation(s)
- Lutz Philipp Breitling
- Division of Clinical Epidemiology and Aging Reseach, German Cancer Research Center, Heidelberg, Germany.
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27
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Um JW, Nygaard HB, Heiss JK, Kostylev MA, Stagi M, Vortmeyer A, Wisniewski T, Gunther EC, Strittmatter SM. Alzheimer amyloid-β oligomer bound to postsynaptic prion protein activates Fyn to impair neurons. Nat Neurosci 2012; 15:1227-35. [PMID: 22820466 PMCID: PMC3431439 DOI: 10.1038/nn.3178] [Citation(s) in RCA: 488] [Impact Index Per Article: 40.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 07/02/2012] [Indexed: 12/21/2022]
Abstract
Amyloid-beta (Aβ) oligomers are thought to trigger Alzheimer’s disease (AD) pathophysiology. Cellular Prion Protein (PrPC) selectively binds oligomeric Aβ and can mediate AD-related phenotypes. Here, we examined the specificity, distribution and signaling from Aβ/PrP complexes, seeking to explain how they might alter the function of NMDA receptors in neurons. PrPC is enriched in post-synaptic densities, and Aβ/PrPC interaction leads to Fyn kinase activation. Soluble Aβ assemblies derived from human AD brain interact with PrPC to activate Fyn. Aβ engagement of PrPC/Fyn signaling yields phosphorylation of the NR2B subunit of NMDA-receptors, which is coupled to an initial increase and then loss of surface NMDA-receptors. Aβ-induced LDH release and dendritic spine loss require both PrPC and Fyn, and human familial AD transgene-induced convulsive seizures do not occur in mice lacking PrPC. These results delineate an Aβ oligomer signal transduction pathway requiring PrPC and Fyn to alter synaptic function with relevance to AD.
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Affiliation(s)
- Ji Won Um
- Cellular Neuroscience, Neurodegeneration and Repair Program, Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, USA
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28
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Griffiths HH, Whitehouse IJ, Hooper NM. Regulation of amyloid-β production by the prion protein. Prion 2012; 6:217-22. [PMID: 22449984 DOI: 10.4161/pri.18988] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Alzheimer disease (AD) is characterized by the amyloidogenic processing of the amyloid precursor protein (APP), culminating in the accumulation of amyloid-β peptides in the brain. The enzymatic action of the β-secretase, BACE1 is the rate-limiting step in this amyloidogenic processing of APP. BACE1 cleavage of wild-type APP (APPWT) is inhibited by the cellular prion protein (PrP (C) ). Our recent study has revealed the molecular and cellular mechanisms behind this observation by showing that PrP (C) directly interacts with the pro-domain of BACE1 in the trans-Golgi network (TGN), decreasing the amount of BACE1 at the cell surface and in endosomes where it cleaves APPWT, while increasing BACE1 in the TGN where it preferentially cleaves APP with the Swedish mutation (APPSwe). PrP (C) deletion in transgenic mice expressing the Swedish and Indiana familial mutations (APPSwe,Ind) failed to affect amyloid-β accumulation, which is explained by the differential subcellular sites of action of BACE1 toward APPWT and APPSwe. This, together with our observation that PrP (C) is reduced in sporadic but not familial AD brain, suggests that PrP (C) plays a key protective role against sporadic AD. It also highlights the need for an APPWT transgenic mouse model to understand the molecular and cellular mechanisms underlying sporadic AD.
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Affiliation(s)
- Heledd H Griffiths
- Faculty of Biological Sciences, Institute of Molecular and Cellular Biology, University of Leeds, Leeds, UK
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