1751
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Stark T, Lieblein T, Pohland M, Kalden E, Freund P, Zangl R, Grewal R, Heilemann M, Eckert GP, Morgner N, Göbel MW. Peptidomimetics That Inhibit and Partially Reverse the Aggregation of Aβ1–42. Biochemistry 2017; 56:4840-4849. [DOI: 10.1021/acs.biochem.7b00223] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | | | | | | | | | | | - Rekha Grewal
- Institute
of Nutritional Sciences, Justus-Liebig-University Giessen, Wilhelmstrasse
20, D-35392 Giessen, Germany
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1752
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Pseudo-peptide amyloid-β blocking inhibitors: molecular dynamics and single molecule force spectroscopy study. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1865:1707-1718. [PMID: 28844735 DOI: 10.1016/j.bbapap.2017.07.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 06/07/2017] [Accepted: 07/25/2017] [Indexed: 12/14/2022]
Abstract
By combining MD simulations and AFS experimental technique, we demonstrated a powerful approach for rational design and single molecule testing of novel inhibitor molecules which can block amyloid-amyloid binding - the first step of toxic amyloid oligomer formation. We designed and tested novel pseudo-peptide amyloid-β (Aβ) inhibitors that bind to the Aβ peptide and effectively prevent amyloid-amyloid binding. First, molecular dynamics (MD) simulations have provided information on the structures and binding characteristics of the designed pseudo-peptides targeting amyloid fragment Aβ (13-23). The binding affinities between the inhibitor and Aβ as well as the inhibitor to itself have been estimated using Umbrella Sampling calculations. Atomic Force Spectroscopy (AFS) was used to experimentally test several proposed inhibitors in their ability to block amyloid-amyloid binding - the first step of toxic amyloid oligomer formation. The experimental AFS data are in a good agreement with theoretical MD calculations and demonstrate that three proposed pseudo-peptides bind to amyloid fragment with different affinities and all effectively prevent Aβ-Aβ binding in similar way. We propose that the designed pseudo-peptides can be used as potential drug candidates to prevent Aβ toxicity in Alzheimer's disease.
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1753
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Theophanides T, Anastassopoulou J. The effects of metal ion contaminants on the double stranded DNA helix and diseases. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2017; 52:1030-1040. [PMID: 28758877 DOI: 10.1080/10934529.2017.1328950] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Mineral metal ions are essential for the maintenance of the reactions that regulate homeostasis and the functions of our body. It is known that the regulation of the neurodegenerative system depends directly on life metal ions, such as Na, K, Mg, Ca, Fe, Mo, Cu, Co, Zn, Cr, Mn, while the toxic metals Cd, Pb, Hg, etc disturb homeostasis, leading to diseases. Particularly significant is the effect of toxic metals on the double stranded forms of DNA and conformations. It was found that the toxic metal ions by reacting specifically with the nucleic bases and electrostatically with the negatively phosphate groups of the DNA backbone cause changes in the structure of the DNA double helix, leading to breaks of single or double strands. Accumulation of these defects affects the protecting systems of the body and induces mutations, eventually leading to serious diseases. There are many metal ions, such as Cr, Al, Cd, Cu, Ni, which by binding directly to DNA molecule or by developing oxidative stress increase the instability of DNA, promoting epigenetic changes that lead to DNA damage. Toxic metal ions induce indirect DNA damage and influence the gene stability by inactivating encoding proteins or by changing the redox potential and the signaling of metalloenzymes.
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Affiliation(s)
- T Theophanides
- a National Technical University of Athens, Chemical Engineering Department, Radiation Chemistry & Biospectroscopy , Zografou Campus, Zografou , Athens , Greece
| | - J Anastassopoulou
- b International Anticancer Research Institute , Kapandritiou-Kalamou Road, Kapandriti , Attiki , Greece
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1754
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Moussa CEH. Beta-secretase inhibitors in phase I and phase II clinical trials for Alzheimer's disease. Expert Opin Investig Drugs 2017; 26:1131-1136. [PMID: 28817311 DOI: 10.1080/13543784.2017.1369527] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION BACE 1 is a protease that cleaves the transmembrane amyloid precursor protein and generates amyloid-β peptides that accumulate in AD brains. No known mutations are identified in the gene encoding BACE1 in AD. However, enzyme levels are elevated in AD and a single residue mutation in amyloid precursor protein protects against protein cleavage by BACE1, suggesting BACE involvement in disease pathogenesis. Drugs that can inhibit BACE1 would theoretically prevent Aβ accumulation and halt AD onset and progression. Areas covered: This review discusses clinical developments of BACE1 inhibitors and focuses on what is learned about these inhibitors as a potential treatment. Expert opinion: BACE1 inhibition as a therapeutic strategy to improve cognition in AD has been challening. Brain-penetrant BACE1 inhibitors have been developed and clinical trials are underway, both safety and efficacy are questionable. Several clinical trials suggest that BACE1 inhibition and other immunotherapies to reduce brain Aβ are insufficient to improve cognition in AD. This may be due to the emphasis on the amyloid hypothesis despite big failures. We may have to seriously consider shifting attention to therapeutic strategies other than BACE1 inhibition or reduction of Aβ alone and pay more attention to simultaneous clearance of tau and Aβ.
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Affiliation(s)
- Charbel E-H Moussa
- a Department of Neurology, Laboratory for Dementia and Parkinsonism, Translational Neurotherapeutics Program , Georgetown University Medical Center , Washington , DC , USA
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1755
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Morena F, Argentati C, Trotta R, Crispoltoni L, Stabile A, Pistilli A, di Baldassarre A, Calafiore R, Montanucci P, Basta G, Pedrinolla A, Smania N, Venturelli M, Schena F, Naro F, Emiliani C, Rende M, Martino S. A Comparison of Lysosomal Enzymes Expression Levels in Peripheral Blood of Mild- and Severe-Alzheimer's Disease and MCI Patients: Implications for Regenerative Medicine Approaches. Int J Mol Sci 2017; 18:ijms18081806. [PMID: 28825628 PMCID: PMC5578193 DOI: 10.3390/ijms18081806] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 08/04/2017] [Accepted: 08/14/2017] [Indexed: 12/22/2022] Open
Abstract
The association of lysosomal dysfunction and neurodegeneration has been documented in several neurodegenerative diseases, including Alzheimer's Disease (AD). Herein, we investigate the association of lysosomal enzymes with AD at different stages of progression of the disease (mild and severe) or with mild cognitive impairment (MCI). We conducted a screening of two classes of lysosomal enzymes: glycohydrolases (β-Hexosaminidase, β-Galctosidase, β-Galactosylcerebrosidase, β-Glucuronidase) and proteases (Cathepsins S, D, B, L) in peripheral blood samples (blood plasma and PBMCs) from mild AD, severe AD, MCI and healthy control subjects. We confirmed the lysosomal dysfunction in severe AD patients and added new findings enhancing the association of abnormal levels of specific lysosomal enzymes with the mild AD or severe AD, and highlighting the difference of AD from MCI. Herein, we showed for the first time the specific alteration of β-Galctosidase (Gal), β-Galactosylcerebrosidase (GALC) in MCI patients. It is notable that in above peripheral biological samples the lysosomes are more sensitive to AD cellular metabolic alteration when compared to levels of Aβ-peptide or Tau proteins, similar in both AD groups analyzed. Collectively, our findings support the role of lysosomal enzymes as potential peripheral molecules that vary with the progression of AD, and make them useful for monitoring regenerative medicine approaches for AD.
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Affiliation(s)
- Francesco Morena
- Department of Chemistry, Biology and Biotechnology, Biochemistry and Molecular Biology Unit, University of Perugia, Perugia 06123, Italy.
| | - Chiara Argentati
- Department of Chemistry, Biology and Biotechnology, Biochemistry and Molecular Biology Unit, University of Perugia, Perugia 06123, Italy.
| | - Rosa Trotta
- Department of Chemistry, Biology and Biotechnology, Biochemistry and Molecular Biology Unit, University of Perugia, Perugia 06123, Italy.
| | - Lucia Crispoltoni
- Department of Surgery and Biomedical Sciences, Section of Human, Clinical and Forensic Anatomy, School of Medicine, University of Perugia, Perugia 06132, Italy.
| | - Anna Stabile
- Department of Surgery and Biomedical Sciences, Section of Human, Clinical and Forensic Anatomy, School of Medicine, University of Perugia, Perugia 06132, Italy.
| | - Alessandra Pistilli
- Department of Surgery and Biomedical Sciences, Section of Human, Clinical and Forensic Anatomy, School of Medicine, University of Perugia, Perugia 06132, Italy.
| | - Angela di Baldassarre
- Department of Aging Medical Science, University of G. d'Annunzio, Chieti e Pescara, Chieti 66100, Italy.
| | - Riccardo Calafiore
- Department of Medicine, Section of Cardiovascular, Endocrine and Metabolic Clinical Physiology and Laboratory for Endocrine Cell Transplants and Bio-hybrid Organs, University of Perugia, Perugia 06132, Italy.
| | - Pia Montanucci
- Department of Medicine, Section of Cardiovascular, Endocrine and Metabolic Clinical Physiology and Laboratory for Endocrine Cell Transplants and Bio-hybrid Organs, University of Perugia, Perugia 06132, Italy.
| | - Giuseppe Basta
- Department of Medicine, Section of Cardiovascular, Endocrine and Metabolic Clinical Physiology and Laboratory for Endocrine Cell Transplants and Bio-hybrid Organs, University of Perugia, Perugia 06132, Italy.
| | - Anna Pedrinolla
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona 37134, Italy.
| | - Nicola Smania
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona 37134, Italy.
| | - Massimo Venturelli
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona 37134, Italy.
| | - Federico Schena
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona 37134, Italy.
| | - Fabio Naro
- Department of Anatomical, Histological, Forensic and Orthopedic Sciences, Sapienza University of Roma, Roma 06100, Italy.
| | - Carla Emiliani
- Department of Chemistry, Biology and Biotechnology, Biochemistry and Molecular Biology Unit, University of Perugia, Perugia 06123, Italy.
| | - Mario Rende
- Department of Surgery and Biomedical Sciences, Section of Human, Clinical and Forensic Anatomy, School of Medicine, University of Perugia, Perugia 06132, Italy.
| | - Sabata Martino
- Department of Chemistry, Biology and Biotechnology, Biochemistry and Molecular Biology Unit, University of Perugia, Perugia 06123, Italy.
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1756
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Frost S, Robinson L, Rowe CC, Ames D, Masters CL, Taddei K, Rainey-Smith SR, Martins RN, Kanagasingam Y. Evaluation of Cholinergic Deficiency in Preclinical Alzheimer's Disease Using Pupillometry. J Ophthalmol 2017; 2017:7935406. [PMID: 28894607 PMCID: PMC5574262 DOI: 10.1155/2017/7935406] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 06/04/2017] [Indexed: 11/17/2022] Open
Abstract
Cortical cholinergic deficiency is prominent in Alzheimer's disease (AD), and published findings of diminished pupil flash response in AD suggest that this deficiency may extend to the visual cortical areas and anterior eye. Pupillometry is a low-cost, noninvasive technique that may be useful for monitoring cholinergic deficits which generally lead to memory and cognitive disorders. The aim of the study was to evaluate pupillometry for early detection of AD by comparing the pupil flash response (PFR) in AD (N = 14) and cognitively normal healthy control (HC, N = 115) participants, with the HC group stratified according to high (N = 38) and low (N = 77) neocortical amyloid burden (NAB). Constriction phase PFR parameters were significantly reduced in AD compared to HC (maximum acceleration p < 0.05, maximum velocity p < 0.0005, average velocity p < 0.005, and constriction amplitude p < 0.00005). The high-NAB HC subgroup had reduced PFR response cross-sectionally, and also a greater decline longitudinally, compared to the low-NAB subgroup, suggesting changes to pupil response in preclinical AD. The results suggest that PFR changes may occur in the preclinical phase of AD. Hence, pupillometry has a potential as an adjunct for noninvasive, cost-effective screening for preclinical AD.
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Affiliation(s)
- Shaun Frost
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Perth, WA, Australia
- Australian e-Health Research Centre, Perth, WA, Australia
| | - Liam Robinson
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Perth, WA, Australia
- Australian e-Health Research Centre, Perth, WA, Australia
| | - Christopher C. Rowe
- Department of Nuclear Medicine and Centre for PET, Austin Health, Melbourne, VIC, Australia
| | - David Ames
- Department of Psychiatry, University of Melbourne, Melbourne, VIC, Australia
- The Mental Health Research Institute (MHRI), University of Melbourne, Melbourne, VIC, Australia
- National Ageing Research Institute, Melbourne, VIC, Australia
| | - Colin L. Masters
- The Mental Health Research Institute (MHRI), University of Melbourne, Melbourne, VIC, Australia
| | - Kevin Taddei
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
| | - Stephanie R. Rainey-Smith
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
- Sir James McCusker Alzheimer's Disease Research Unit, Hollywood Private Hospital, Perth, WA, Australia
| | - Ralph N. Martins
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
- Sir James McCusker Alzheimer's Disease Research Unit, Hollywood Private Hospital, Perth, WA, Australia
- School of Biomedical Sciences, Macquarie University, North Ryde, NSW, Australia
- School of Psychiatry and Clinical Neurosciences, University of Western Australia, Crawley, WA, Australia
| | - Yogesan Kanagasingam
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Perth, WA, Australia
- Australian e-Health Research Centre, Perth, WA, Australia
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1757
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Alzheimer's disease as oligomeropathy. Neurochem Int 2017; 119:57-70. [PMID: 28821400 DOI: 10.1016/j.neuint.2017.08.010] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/30/2017] [Accepted: 08/13/2017] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease (AD) is the most common age-related neurodegenerative disorder and is characterized by pathological aggregates of amyloid β-protein (Aβ) and tau protein. On the basis of genetic evidence, biochemical data, and animal models, Aβ has been suggested to be responsible for the pathogenesis of AD (the amyloid hypothesis). Aβ molecules tend to aggregate to form oligomers, protofibrils, and mature fibrils. Although mature fibrils in the final stage have been thought to be the cause of AD pathogenesis, recent studies using synthetic Aβ peptides, a cell culture model, Aβ precursor protein transgenic mice models, and human samples, such as cerebrospinal fluids and postmortem brains of AD patients, suggest that pre-fibrillar forms (oligomers of Aβ) are more deleterious than are extracellular fibril forms. Based on this recent evidence showing that oligomers have a central role in the pathogenesis of AD, the term "oligomeropathy" could be used to define AD and other protein-misfolding diseases. In this review, I discuss recent developments in the "oligomer hypothesis" including our research findings regarding the pathogenesis of AD.
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1758
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Shi JM, Zhang L, Liu EQ. Dissecting the behaviour of β-amyloid peptide variants during oligomerization and fibrillation. J Pept Sci 2017; 23:810-817. [PMID: 28795459 DOI: 10.1002/psc.3028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 07/06/2017] [Accepted: 07/10/2017] [Indexed: 12/20/2022]
Abstract
The oligomerization and fibrillation of β-amyloid (Aβ) peptides are important events in the pathogenesis of Alzheimer's disease. However, the motifs within the Aβ sequence that contribute to oligomerization and fibrillation and the complex interplay among these short motifs are unclear. In this study, the oligomerization and fibrillation abilities of the Aβ variants Aβ1-28, Aβ1-36, Aβ11-42, Aβ17-42, Aβ1-40 and Aβ1-42 were examined by thioflavin T fluorescence, western blotting and transmission electron microscopy. Compared with two C-terminal-truncated peptides (i.e. Aβ1-28 and Aβ1-36), Aβ11-42, Aβ17-42 and Aβ1-42 had stronger abilities to form oligomers. This indicated that amino acids 37-42 strengthen the β-hairpin structure of Aβ. Both Aβ1-42 and Aβ1-40 could form fibres, but Aβ17-42 formed irregular fibres, suggesting that amino acids 1-17 were essential for Aβ fibre formation. Aβ1-28 and Aβ1-36 exhibited weak oligomerization and fibrillation, implying that they formed an unstable β-hairpin structure owing to the incomplete C-terminal region. Intermediate peptides were likely to form a stable structure, consistent with previous results. This work explains the roles and interplay among motifs within Aβ during oligomerization and fibrillation. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.
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Affiliation(s)
- Jing-Ming Shi
- Research Institute of Atherosclerotic Disease, Xi'an Jiaotong University Cardiovascular Research Center, Xi'an, 710061, China.,School of Medicine, Xizang Minzu University, Xianyang, 712082, China
| | - Lin Zhang
- Department of Biochemistry and Molecular Biology, Xi'an Jiaotong University, Xi'an, 710061, China
| | - En-Qi Liu
- Research Institute of Atherosclerotic Disease, Xi'an Jiaotong University Cardiovascular Research Center, Xi'an, 710061, China
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1759
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Pitt J, Wilcox KC, Tortelli V, Diniz LP, Oliveira MS, Dobbins C, Yu XW, Nandamuri S, Gomes FCA, DiNunno N, Viola KL, De Felice FG, Ferreira ST, Klein WL. Neuroprotective astrocyte-derived insulin/insulin-like growth factor 1 stimulates endocytic processing and extracellular release of neuron-bound Aβ oligomers. Mol Biol Cell 2017; 28:2623-2636. [PMID: 28963439 PMCID: PMC5620371 DOI: 10.1091/mbc.e17-06-0416] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 07/31/2017] [Indexed: 12/19/2022] Open
Abstract
Synaptopathy underlying memory deficits in Alzheimer's disease (AD) is increasingly thought to be instigated by toxic oligomers of the amyloid beta peptide (AβOs). Given the long latency and incomplete penetrance of AD dementia with respect to Aβ pathology, we hypothesized that factors present in the CNS may physiologically protect neurons from the deleterious impact of AβOs. Here we employed physically separated neuron-astrocyte cocultures to investigate potential non-cell autonomous neuroprotective factors influencing AβO toxicity. Neurons cultivated in the absence of an astrocyte feeder layer showed abundant AβO binding to dendritic processes and associated synapse deterioration. In contrast, neurons in the presence of astrocytes showed markedly reduced AβO binding and synaptopathy. Results identified the protective factors released by astrocytes as insulin and insulin-like growth factor-1 (IGF1). The protective mechanism involved release of newly bound AβOs into the extracellular medium dependent upon trafficking that was sensitive to exosome pathway inhibitors. Delaying insulin treatment led to AβO binding that was no longer releasable. The neuroprotective potential of astrocytes was itself sensitive to chronic AβO exposure, which reduced insulin/IGF1 expression. Our findings support the idea that physiological protection against synaptotoxic AβOs can be mediated by astrocyte-derived insulin/IGF1, but that this protection itself is vulnerable to AβO buildup.
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Affiliation(s)
- Jason Pitt
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208.,Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Kyle C Wilcox
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
| | - Vanessa Tortelli
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil
| | - Luan Pereira Diniz
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil
| | - Maira S Oliveira
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil
| | - Cassandra Dobbins
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
| | - Xiao-Wen Yu
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Sathwik Nandamuri
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
| | - Flávia C A Gomes
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil
| | - Nadia DiNunno
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
| | - Kirsten L Viola
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
| | - Fernanda G De Felice
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil.,Centre for Neuroscience Studies, Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Sergio T Ferreira
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil.,Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro RJ 21944-590, Brazil
| | - William L Klein
- Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208
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1760
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Wang Y, Yan T, Lu H, Yin W, Lin B, Fan W, Zhang X, Fernandez-Funez P. Lessons from Anti-Amyloid-β Immunotherapies in Alzheimer Disease: Aiming at a Moving Target. NEURODEGENER DIS 2017; 17:242-250. [DOI: 10.1159/000478741] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 06/16/2017] [Indexed: 11/19/2022] Open
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1761
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Chandra B, Mithu VS, Bhowmik D, Das AK, Sahoo B, Maiti S, Madhu PK. Curcumin Dictates Divergent Fates for the Central Salt Bridges in Amyloid-β 40 and Amyloid-β 42. Biophys J 2017; 112:1597-1608. [PMID: 28445751 DOI: 10.1016/j.bpj.2017.02.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 02/02/2017] [Accepted: 02/07/2017] [Indexed: 12/25/2022] Open
Abstract
There are three specific regions in the Amyloid beta (Aβ) peptide sequence where variations cause enhanced toxicity in Alzheimer's disease: the N-terminus, the central salt bridge, and the C-terminus. Here, we investigate if there is a close conformational connection between these three regions, which may suggest a concerted mechanism of toxicity. We measure the effects of Zn2+ and curcumin on Aβ40, and compare these with their previously reported effects on Aβ42. Aβ42 and Aβ40 differ only near the C-terminus, where curcumin interacts, while Zn2+ interacts near the N-terminus. Therefore, this comparison should help us differentiate the effect of modulating the C- and the N-termini. We find that curcumin allows fibril-like structures containing the salt bridge to emerge in the mature Aβ40 aggregates, but not in Aβ42. In contrast, we find no difference in the effects of Zn+2 on Aβ40 and Aβ42. In the presence of Zn+2, both of these fail to form proper fibrils, and the salt bridge remains disrupted. These results indicate that modulations of the Aβ termini can determine the fate of a salt bridge far away in the sequence, and this has significant consequences for Aβ toxicity. We also infer that small molecules can alter oligomer-induced toxicity by modulating the aggregation pathway, without substantially changing the final product of aggregation.
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Affiliation(s)
- Bappaditya Chandra
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | | | - Debanjan Bhowmik
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Anand Kant Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Bankanidhi Sahoo
- TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Narsinghi, Hyderabad, India
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India.
| | - Perunthiruthy K Madhu
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India; TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Narsinghi, Hyderabad, India.
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1762
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Impact of aging immune system on neurodegeneration and potential immunotherapies. Prog Neurobiol 2017; 157:2-28. [PMID: 28782588 DOI: 10.1016/j.pneurobio.2017.07.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 07/25/2017] [Accepted: 07/28/2017] [Indexed: 12/19/2022]
Abstract
The interaction between the nervous and immune systems during aging is an area of avid interest, but many aspects remain unclear. This is due, not only to the complexity of the aging process, but also to a mutual dependency and reciprocal causation of alterations and diseases between both the nervous and immune systems. Aging of the brain drives whole body systemic aging, including aging-related changes of the immune system. In turn, the immune system aging, particularly immunosenescence and T cell aging initiated by thymic involution that are sources of chronic inflammation in the elderly (termed inflammaging), potentially induces brain aging and memory loss in a reciprocal manner. Therefore, immunotherapeutics including modulation of inflammation, vaccination, cellular immune therapies and "protective autoimmunity" provide promising approaches to rejuvenate neuroinflammatory disorders and repair brain injury. In this review, we summarize recent discoveries linking the aging immune system with the development of neurodegeneration. Additionally, we discuss potential rejuvenation strategies, focusing aimed at targeting the aging immune system in an effort to prevent acute brain injury and chronic neurodegeneration during aging.
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1763
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Cummings J. Lessons Learned from Alzheimer Disease: Clinical Trials with Negative Outcomes. Clin Transl Sci 2017; 11:147-152. [PMID: 28767185 PMCID: PMC5866992 DOI: 10.1111/cts.12491] [Citation(s) in RCA: 183] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 06/28/2017] [Indexed: 02/06/2023] Open
Affiliation(s)
- Jeffrey Cummings
- Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, Nevada, USA
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1764
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Abstract
Alzheimer's disease (AD) affects more than 5 million Americans, with substantial consequences for individuals with AD, families, and society in terms of morbidity, mortality, and healthcare costs. With disease-modifying treatment trials unsuccessful at the present time and only medications to treat symptoms available, an emerging approach is prevention. Advances in diagnostic criteria, biomarker development, and greater understanding of the biophysiological basis of AD make these initiatives feasible. Ongoing pharmacological trials using anti-amyloid therapies are underway in sporadic and genetic forms of AD, although a large number of modifiable risk factors for AD have been identified in observational studies, many of which do not appear to exert effects through amyloid or tau. This suggests that prevention studies focusing on risk reduction and lifestyle modification may offer additional benefits. Rather than relying solely on large-sample, long-duration, randomized clinical trial designs, a precision medicine approach using N-of-1 trials may provide more-rapid information on whether personalized prevention plans can improve person-centered outcomes. Because there appear to be multiple pathways to developing AD, there may also be multiple ways to prevent or delay the onset of AD. Even if these precision approaches alone are not successful in preventing AD, they may greatly improve the likelihood of amyloid- or tau-specific therapies to reach their endpoints by reducing comorbidities. Keeping this in mind, dementia may be a disorder that develops over a lifetime, with individualized ways to build a better brain as we age.
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Affiliation(s)
- James E Galvin
- Comprehensive Center for Brain Health, Department of Integrated Medical Sciences, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida
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1765
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Harn NR, Hunt SL, Hill J, Vidoni E, Perry M, Burns JM. Augmenting Amyloid PET Interpretations With Quantitative Information Improves Consistency of Early Amyloid Detection. Clin Nucl Med 2017; 42:577-581. [PMID: 28574875 PMCID: PMC5491352 DOI: 10.1097/rlu.0000000000001693] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE Establishing reliable methods for interpreting elevated cerebral amyloid-β plaque on PET scans is increasingly important for radiologists, as availability of PET imaging in clinical practice increases. We examined a 3-step method to detect plaque in cognitively normal older adults, focusing on the additive value of quantitative information during the PET scan interpretation process. METHODS Fifty-five F-florbetapir PET scans were evaluated by 3 experienced raters. Scans were first visually interpreted as having "elevated" or "nonelevated" plaque burden ("Visual Read"). Images were then processed using a standardized quantitative analysis software (MIMneuro) to generate whole brain and region of interest SUV ratios. This "Quantitative Read" was considered elevated if at least 2 of 6 regions of interest had an SUV ratio of more than 1.1. The final interpretation combined both visual and quantitative data together ("VisQ Read"). Cohen kappa values were assessed as a measure of interpretation agreement. RESULTS Plaque was elevated in 25.5% to 29.1% of the 165 total Visual Reads. Interrater agreement was strong (kappa = 0.73-0.82) and consistent with reported values. Quantitative Reads were elevated in 45.5% of participants. Final VisQ Reads changed from initial Visual Reads in 16 interpretations (9.7%), with most changing from "nonelevated" Visual Reads to "elevated." These changed interpretations demonstrated lower plaque quantification than those initially read as "elevated" that remained unchanged. Interrater variability improved for VisQ Reads with the addition of quantitative information (kappa = 0.88-0.96). CONCLUSIONS Inclusion of quantitative information increases consistency of PET scan interpretations for early detection of cerebral amyloid-β plaque accumulation.
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Affiliation(s)
- Nicholas R Harn
- From the Departments of *Radiology, †Biostatistics, and ‡Neurology, University of Kansas Medical Center, Kansas City, KS
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1766
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Frisoni GB, Boccardi M, Barkhof F, Blennow K, Cappa S, Chiotis K, Démonet JF, Garibotto V, Giannakopoulos P, Gietl A, Hansson O, Herholz K, Jack CR, Nobili F, Nordberg A, Snyder HM, Ten Kate M, Varrone A, Albanese E, Becker S, Bossuyt P, Carrillo MC, Cerami C, Dubois B, Gallo V, Giacobini E, Gold G, Hurst S, Lönneborg A, Lovblad KO, Mattsson N, Molinuevo JL, Monsch AU, Mosimann U, Padovani A, Picco A, Porteri C, Ratib O, Saint-Aubert L, Scerri C, Scheltens P, Schott JM, Sonni I, Teipel S, Vineis P, Visser PJ, Yasui Y, Winblad B. Strategic roadmap for an early diagnosis of Alzheimer's disease based on biomarkers. Lancet Neurol 2017; 16:661-676. [PMID: 28721928 DOI: 10.1016/s1474-4422(17)30159-x] [Citation(s) in RCA: 401] [Impact Index Per Article: 57.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 04/27/2017] [Accepted: 04/28/2017] [Indexed: 12/15/2022]
Abstract
The diagnosis of Alzheimer's disease can be improved by the use of biological measures. Biomarkers of functional impairment, neuronal loss, and protein deposition that can be assessed by neuroimaging (ie, MRI and PET) or CSF analysis are increasingly being used to diagnose Alzheimer's disease in research studies and specialist clinical settings. However, the validation of the clinical usefulness of these biomarkers is incomplete, and that is hampering reimbursement for these tests by health insurance providers, their widespread clinical implementation, and improvements in quality of health care. We have developed a strategic five-phase roadmap to foster the clinical validation of biomarkers in Alzheimer's disease, adapted from the approach for cancer biomarkers. Sufficient evidence of analytical validity (phase 1 of a structured framework adapted from oncology) is available for all biomarkers, but their clinical validity (phases 2 and 3) and clinical utility (phases 4 and 5) are incomplete. To complete these phases, research priorities include the standardisation of the readout of these assays and thresholds for normality, the evaluation of their performance in detecting early disease, the development of diagnostic algorithms comprising combinations of biomarkers, and the development of clinical guidelines for the use of biomarkers in qualified memory clinics.
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Affiliation(s)
- Giovanni B Frisoni
- Laboratory of Neuroimaging of Aging (LANVIE), University Hospitals and University of Geneva, Geneva, Switzerland; Department of Internal Medicine, University Hospitals and University of Geneva, Geneva, Switzerland.
| | - Marina Boccardi
- Laboratory of Neuroimaging of Aging (LANVIE), University Hospitals and University of Geneva, Geneva, Switzerland; Laboratory of Alzheimer Neuroimaging and Epidemiology (LANE), IRCCS S Giovanni di Dio-Fatebenefratelli, Brescia, Italy
| | - Frederik Barkhof
- Department of Radiology and Nuclear Medicine, VU University Medical Centre, Amsterdam, Netherlands; Institute of Neurology, University College London, London, UK; Institute of Healthcare Engineering, University College London, London, UK; European Society of Neuroradiology, Zurich, Switzerland
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden; International Federation of Clinical Chemistry and Laboratory Medicine Working Group for CSF proteins (IFCC WG-CSF), Gothenburg, Sweden
| | - Stefano Cappa
- Department of Radiology and Nuclear Medicine, VU University Medical Centre, Amsterdam, Netherlands; Istituto Universitario di Studi Superiori di Pavia, Pavia, Italy, on behalf of Federation of European Neuropsychological Societies
| | - Konstantinos Chiotis
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Translational Alzheimer Neurobiology, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Jean-Francois Démonet
- Leenards Memory Centre, Department of Clinical Neuroscience, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Valentina Garibotto
- Nuclear Medicine and Molecular Imaging Division, University Hospitals and University of Geneva, Geneva, Switzerland
| | | | - Anton Gietl
- Institute for Regenerative Medicine-IREM, University of Zurich Campus Schlieren, Zurich, Switzerland
| | - Oskar Hansson
- Memory Clinic, Skåne University Hospital, Lund, Sweden; Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Lund, Sweden
| | - Karl Herholz
- Division of Neuroscience and Experimental Psychology, University of Manchester, Manchester, UK
| | | | - Flavio Nobili
- Department of Neuroscience (DINOGMI), University of Genoa, Genoa, Italy; IRCCS AOU San Martino-IST, Genoa, Italy, on behalf of the European Association of Nuclear Medicine
| | - Agneta Nordberg
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Translational Alzheimer Neurobiology, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden; Department of Geriatric Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | | | - Mara Ten Kate
- Department of Neurology, Alzheimer Centre, VU University Medical Centre, Amsterdam, Netherlands
| | - Andrea Varrone
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Emiliano Albanese
- Department of Psychiatry, University Hospitals and University of Geneva, Geneva, Switzerland
| | | | - Patrick Bossuyt
- Clinical Epidemiology, University of Amsterdam, Amsterdam, Netherlands, on behalf of the European Federation of Laboratory Medicine
| | | | - Chiara Cerami
- Clinical Neuroscience Department, Vita-Salute San Raffaele University, Milan, Italy; Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy
| | - Bruno Dubois
- Institut de la Mémoire et de la Maladie d'Alzheimer, Hôpital Pitié Salpêtrière, UPMC University Paris 6, Paris, France
| | - Valentina Gallo
- Centre for Primary Care and Public Health, Barts and The London School of Medicine, Blizard Institute, Queen Mary University of London, London, UK
| | - Ezio Giacobini
- Department of Internal Medicine, University Hospitals and University of Geneva, Geneva, Switzerland
| | - Gabriel Gold
- Service of Geriatrics, Department of Internal Medicine Rehabilitation and Geriatrics, University Hospitals and University of Geneva, Geneva, Switzerland
| | - Samia Hurst
- Institute for Ethics, History, and the Humanities, University Hospitals and University of Geneva, Geneva, Switzerland
| | - Anders Lönneborg
- Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Lund, Sweden
| | - Karl-Olof Lovblad
- Diagnostic and Interventional Neuroradiology, University Hospital of Geneva, Geneva, Switzerland
| | - Niklas Mattsson
- Memory Clinic, Skåne University Hospital, Lund, Sweden; Department of Neurology, Skåne University Hospital, Lund, Sweden; Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Lund, Sweden
| | - José-Luis Molinuevo
- Barcelona Beta Brain Research Centre, Pasqual Maragall Foundation, Barcelona, Spain
| | - Andreas U Monsch
- Memory Clinic, University Centre for Medicine of Ageing, Felix Platter Hospital, Basel, Switzerland
| | - Urs Mosimann
- Department of Old Age Psychiatry, University of Bern, Bern, Switzerland
| | - Alessandro Padovani
- Department of Clinical Neurosciences, Faculty of Medicine, University of Brescia, Brescia, Italy
| | - Agnese Picco
- Laboratory of Neuroimaging of Aging (LANVIE), University Hospitals and University of Geneva, Geneva, Switzerland; Department of Neuroscience (DINOGMI), University of Genoa, Genoa, Italy
| | - Corinna Porteri
- Bioethics Unit, IRCCS S Giovanni di Dio-Fatebenefratelli, Brescia, Italy
| | - Osman Ratib
- Department of Radiology, University Hospital of Geneva, Geneva, Switzerland; Division of Nuclear Medicine, University Hospital of Geneva, Geneva, Switzerland
| | - Laure Saint-Aubert
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Translational Alzheimer Neurobiology, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Charles Scerri
- Department of Pathology, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Alzheimer Europe, Luxembourg, Luxembourg
| | - Philip Scheltens
- Department of Neurology, Alzheimer Centre, VU University Medical Centre, Amsterdam, Netherlands
| | | | - Ida Sonni
- PET Centre, Department of Clinical Neurosciences, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden; Division of Nuclear Medicine and Molecular Imaging, Stanford University, Standford, CA, USA
| | - Stefan Teipel
- German Center for Neurodegenerative Diseases (DZNE)-Rostock/Greifswald, Rostock, Germany; Department of Psychosomatic Medicine, University of Rostock, Rostock, Germany
| | - Paolo Vineis
- Faculty of Medicine, Imperial College London, London, UK
| | - Pieter Jelle Visser
- Department of Neurology, Alzheimer Centre, VU University Medical Centre, Amsterdam, Netherlands; Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Yutaka Yasui
- St Jude Children's Research Hospital, Memphis, TN, USA
| | - Bengt Winblad
- Department of Geriatric Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden; Department of Neurobiology, Care Siences and Society, Centre for Alzheimer Research, Division of Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden; European Alzheimer's Disease Consortium
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1767
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Saltmarche AE, Naeser MA, Ho KF, Hamblin MR, Lim L. Significant Improvement in Cognition in Mild to Moderately Severe Dementia Cases Treated with Transcranial Plus Intranasal Photobiomodulation: Case Series Report. Photomed Laser Surg 2017; 35:432-441. [PMID: 28186867 PMCID: PMC5568598 DOI: 10.1089/pho.2016.4227] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/27/2016] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVE This study investigated whether patients with mild to moderately severe dementia or possible Alzheimer's disease (AD) with Mini-Mental State Exam (MMSE) Baseline scores of 10-24 would improve when treated with near-infrared photobiomodulation (PBM) therapy. BACKGROUND Animal studies have presented the potential of PBM for AD. Dysregulation of the brain's default mode network (DMN) has been associated with AD, presenting the DMN as an identifiable target for PBM. MATERIALS AND METHODS The study used 810 nm, 10 Hz pulsed, light-emitting diode devices combining transcranial plus intranasal PBM to treat the cortical nodes of the DMN (bilateral mesial prefrontal cortex, precuneus/posterior cingulate cortex, angular gyrus, and hippocampus). Five patients with mild to moderately severe cognitive impairment were entered into 12 weeks of active treatment as well as a follow-up no-treatment, 4-week period. Patients were assessed with the MMSE and Alzheimer's Disease Assessment Scale (ADAS-cog) tests. The protocol involved weekly, in-clinic use of a transcranial-intranasal PBM device; and daily at-home use of an intranasal-only device. RESULTS There was significant improvement after 12 weeks of PBM (MMSE, p < 0.003; ADAS-cog, p < 0.023). Increased function, better sleep, fewer angry outbursts, less anxiety, and wandering were reported post-PBM. There were no negative side effects. Precipitous declines were observed during the follow-up no-treatment, 4-week period. This is the first completed PBM case series to report significant, cognitive improvement in mild to moderately severe dementia and possible AD cases. CONCLUSIONS Results suggest that larger, controlled studies are warranted. PBM shows potential for home treatment of patients with dementia and AD.
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Affiliation(s)
| | - Margaret A. Naeser
- VA Boston Healthcare System, Boston, Massachusetts
- Department of Neurology, Boston University School of Medicine, Boston, Massachusetts
| | | | - Michael R Hamblin
- Harvard Medical School, Boston, Massachusetts
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts
| | - Lew Lim
- Vielight, Inc., Toronto, Ontario, Canada
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1768
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Schoch KM, Miller TM. Antisense Oligonucleotides: Translation from Mouse Models to Human Neurodegenerative Diseases. Neuron 2017. [PMID: 28641106 DOI: 10.1016/j.neuron.2017.04.010] [Citation(s) in RCA: 199] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Multiple neurodegenerative diseases are characterized by single-protein dysfunction and aggregation. Treatment strategies for these diseases have often targeted downstream pathways to ameliorate consequences of protein dysfunction; however, targeting the source of that dysfunction, the affected protein itself, seems most judicious to achieve a highly effective therapeutic outcome. Antisense oligonucleotides (ASOs) are small sequences of DNA able to target RNA transcripts, resulting in reduced or modified protein expression. ASOs are ideal candidates for the treatment of neurodegenerative diseases, given numerous advancements made to their chemical modifications and delivery methods. Successes achieved in both animal models and human clinical trials have proven ASOs both safe and effective. With proper considerations in mind regarding the human applicability of ASOs, we anticipate ongoing in vivo research and clinical trial development of ASOs for the treatment of neurodegenerative diseases.
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Affiliation(s)
- Kathleen M Schoch
- Department of Neurology, Hope Center for Neurological Disorders, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Timothy M Miller
- Department of Neurology, Hope Center for Neurological Disorders, Washington University in St. Louis, St. Louis, MO 63110, USA.
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1769
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Sasaguri H, Nilsson P, Hashimoto S, Nagata K, Saito T, De Strooper B, Hardy J, Vassar R, Winblad B, Saido TC. APP mouse models for Alzheimer's disease preclinical studies. EMBO J 2017; 36:2473-2487. [PMID: 28768718 PMCID: PMC5579350 DOI: 10.15252/embj.201797397] [Citation(s) in RCA: 454] [Impact Index Per Article: 64.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 06/09/2017] [Accepted: 07/07/2017] [Indexed: 12/11/2022] Open
Abstract
Animal models of human diseases that accurately recapitulate clinical pathology are indispensable for understanding molecular mechanisms and advancing preclinical studies. The Alzheimer's disease (AD) research community has historically used first‐generation transgenic (Tg) mouse models that overexpress proteins linked to familial AD (FAD), mutant amyloid precursor protein (APP), or APP and presenilin (PS). These mice exhibit AD pathology, but the overexpression paradigm may cause additional phenotypes unrelated to AD. Second‐generation mouse models contain humanized sequences and clinical mutations in the endogenous mouse App gene. These mice show Aβ accumulation without phenotypes related to overexpression but are not yet a clinical recapitulation of human AD. In this review, we evaluate different APP mouse models of AD, and review recent studies using the second‐generation mice. We advise AD researchers to consider the comparative strengths and limitations of each model against the scientific and therapeutic goal of a prospective preclinical study.
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Affiliation(s)
- Hiroki Sasaguri
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan .,Department of Neurology and Neurological Science, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan
| | - Per Nilsson
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan.,Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet, Huddinge, Sweden
| | - Shoko Hashimoto
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan
| | - Kenichi Nagata
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan
| | - Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan.,Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Bart De Strooper
- Dementia Research Institute, University College London, London, UK.,Department for Neurosciences, KU Leuven, Leuven, Belgium.,VIB Center for Brain and Disease Research, Leuven, Belgium
| | - John Hardy
- Reta Lila Research Laboratories and the Department of Molecular Neuroscience, University College London Institute of Neurology, London, UK
| | - Robert Vassar
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Bengt Winblad
- Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet, Huddinge, Sweden
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan
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1770
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Piechotta A, Parthier C, Kleinschmidt M, Gnoth K, Pillot T, Lues I, Demuth HU, Schilling S, Rahfeld JU, Stubbs MT. Structural and functional analyses of pyroglutamate-amyloid-β-specific antibodies as a basis for Alzheimer immunotherapy. J Biol Chem 2017; 292:12713-12724. [PMID: 28623233 PMCID: PMC5535044 DOI: 10.1074/jbc.m117.777839] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 06/07/2017] [Indexed: 12/22/2022] Open
Abstract
Alzheimer disease is associated with deposition of the amyloidogenic peptide Aβ in the brain. Passive immunization using Aβ-specific antibodies has been demonstrated to reduce amyloid deposition both in vitro and in vivo Because N-terminally truncated pyroglutamate (pE)-modified Aβ species (AβpE3) exhibit enhanced aggregation potential and propensity to form toxic oligomers, they represent particularly attractive targets for antibody therapy. Here we present three separate monoclonal antibodies that specifically recognize AβpE3 with affinities of 1-10 nm and inhibit AβpE3 fibril formation in vitro. In vivo application of one of these resulted in improved memory in AβpE3 oligomer-treated mice. Crystal structures of Fab-AβpE3 complexes revealed two distinct binding modes for the peptide. Juxtaposition of pyroglutamate pE3 and the F4 side chain (the "pEF head") confers a pronounced bulky hydrophobic nature to the AβpE3 N terminus that might explain the enhanced aggregation properties of the modified peptide. The deep burial of the pEF head by two of the antibodies explains their high target specificity and low cross-reactivity, making them promising candidates for the development of clinical antibodies.
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Affiliation(s)
- Anke Piechotta
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Institute of Biotechnology, Martin Luther University, 06108 Halle-Wittenberg, Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany
| | - Christoph Parthier
- Institute of Biotechnology, Martin Luther University, 06108 Halle-Wittenberg, Germany
| | - Martin Kleinschmidt
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany
| | - Kathrin Gnoth
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany
| | | | - Inge Lues
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany
| | - Hans-Ulrich Demuth
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany
| | - Stephan Schilling
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany
| | - Jens-Ulrich Rahfeld
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany.
| | - Milton T Stubbs
- Institute of Biotechnology, Martin Luther University, 06108 Halle-Wittenberg, Germany.
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1771
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Nakamura A, Cuesta P, Kato T, Arahata Y, Iwata K, Yamagishi M, Kuratsubo I, Kato K, Bundo M, Diers K, Fernández A, Maestú F, Ito K. Early functional network alterations in asymptomatic elders at risk for Alzheimer's disease. Sci Rep 2017; 7:6517. [PMID: 28747760 PMCID: PMC5529571 DOI: 10.1038/s41598-017-06876-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 06/20/2017] [Indexed: 01/23/2023] Open
Abstract
Amyloid-β (Aβ) deposition is known to starts decades before the onset of clinical symptoms of Alzheimer's disease (AD), however, the detailed pathophysiological processes underlying this preclinical period are not well understood. This study aimed to investigate functional network alterations in cognitively intact elderly individuals at risk for AD, and assessed the association between these network alterations and changes in Aβ deposition, glucose metabolism, and brain structure. Forty-five cognitively normal elderly subjects, who were classified into Aβ-positive (CN+) and Aβ-negative (CN-) groups using 11C-Pittsburgh compound B PET, underwent resting state magnetoencephalography measurements, 18F-fluorodeoxyglucose PET (FDG-PET) and structural MRI. Results demonstrated that in the CN+ group, functional connectivity (FC) within the precuneus was significantly decreased, whereas it was significantly enhanced between the precuneus and the bilateral inferior parietal lobules in the low-frequency bands (theta and delta). These changes were suggested to be associated with local cerebral Aβ deposition. Most of Aβ+ individuals in this study did not show any metabolic or anatomical changes, and there were no significant correlations between FC values and FDG-PET or MRI volumetry data. These results demonstrate that functional network alterations, which occur in association with Aβ deposition, are detectable using magnetoencephalography before metabolic and anatomical changes are seen.
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Affiliation(s)
- Akinori Nakamura
- Department of Clinical and Experimental Neuroimaging, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan.
| | - Pablo Cuesta
- Department of Clinical and Experimental Neuroimaging, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan.,Laboratory of Cognitive and Computational Neuroscience, Center for Biomedical Technology, Complutense University of Madrid and Technical University of Madrid, Madrid, Spain.,Department of Basic Psychology II, Complutense University of Madrid, Madrid, Spain
| | - Takashi Kato
- Department of Clinical and Experimental Neuroimaging, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan.,National Hospital for Geriatric Medicine, National Center for Geriatrics and Gerontology, Obu, Japan
| | - Yutaka Arahata
- National Hospital for Geriatric Medicine, National Center for Geriatrics and Gerontology, Obu, Japan
| | - Kaori Iwata
- Department of Clinical and Experimental Neuroimaging, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan
| | - Misako Yamagishi
- Department of Clinical and Experimental Neuroimaging, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan
| | - Izumi Kuratsubo
- Department of Clinical and Experimental Neuroimaging, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan
| | - Kimiko Kato
- Department of Clinical and Experimental Neuroimaging, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan
| | - Masahiko Bundo
- Department of Clinical and Experimental Neuroimaging, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan.,National Hospital for Geriatric Medicine, National Center for Geriatrics and Gerontology, Obu, Japan
| | - Kersten Diers
- Department of Psychology, Technische Universität Dresden, Dresden, Germany
| | - Alberto Fernández
- Laboratory of Cognitive and Computational Neuroscience, Center for Biomedical Technology, Complutense University of Madrid and Technical University of Madrid, Madrid, Spain.,Department of Psychiatry, Faculty of Medicine, Complutense University of Madrid, Madrid, Spain
| | - Fernando Maestú
- Laboratory of Cognitive and Computational Neuroscience, Center for Biomedical Technology, Complutense University of Madrid and Technical University of Madrid, Madrid, Spain.,Department of Basic Psychology II, Complutense University of Madrid, Madrid, Spain
| | - Kengo Ito
- Department of Clinical and Experimental Neuroimaging, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan.,National Hospital for Geriatric Medicine, National Center for Geriatrics and Gerontology, Obu, Japan
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1772
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De Simone A, Bartolini M, Baschieri A, Apperley KYP, Chen HH, Guardigni M, Montanari S, Kobrlova T, Soukup O, Valgimigli L, Andrisano V, Keillor JW, Basso M, Milelli A. Hydroxy-substituted trans-cinnamoyl derivatives as multifunctional tools in the context of Alzheimer's disease. Eur J Med Chem 2017; 139:378-389. [PMID: 28810189 DOI: 10.1016/j.ejmech.2017.07.058] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 05/29/2017] [Accepted: 07/24/2017] [Indexed: 11/25/2022]
Abstract
Alzheimer's disease (AD) is a multifactorial pathology that requires multifaceted agents able to address its peculiar nature. In recent years, a plethora of proteins and biochemical pathways has been proposed as possible targets to counteract neurotoxicity. Although the complex scenario is not completely elucidated, close relationships are emerging among some of these actors. In particular, increasing evidence has shown that aggregation of amyloid beta (Aβ), glycogen synthase kinase 3β (GSK-3β) and oxidative stress are strictly interconnected and their concomitant modulation may have a positive and synergic effect in contrasting AD-related impairments. We designed compound 3 which demonstrated the ability to inhibit both GSK-3β (IC50 = 24.36 ± 0.01 μM) and Aβ42 self-aggregation (IC50 = 9.0 ± 1.4 μM), to chelate copper (II) and to act as exceptionally strong radical scavenger (kinh = 6.8 ± 0.5 · 105 M-1s-1) even in phosphate buffer at pH 7.4 (kinh = 3.2 ± 0.5 · 105 M-1s-1). Importantly, compound 3 showed high-predicted blood-brain barrier permeability, did not exert any significant cytotoxic effects in immature cortical neurons up to 50 μM and showed neuroprotective properties at micromolar concentration against toxic insult induced by glutamate.
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Affiliation(s)
- Angela De Simone
- Department for Life Quality Studies, Alma Mater Studiorum-University of Bologna, Corso d'Augusto 237, 47921 Rimini, Italy
| | - Manuela Bartolini
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Via Belmeloro 6, 40126 Bologna, Italy
| | - Andrea Baschieri
- Department of Chemistry "G. Ciamician", Alma Mater Studiorum-University of Bologna, Via S. Giacomo 11, 40126 Bologna, Italy
| | - Kim Y P Apperley
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie-Curie, Ottawa, ON, K1N 6N5, Canada
| | - Huan Huan Chen
- Department for Life Quality Studies, Alma Mater Studiorum-University of Bologna, Corso d'Augusto 237, 47921 Rimini, Italy
| | - Melissa Guardigni
- Department for Life Quality Studies, Alma Mater Studiorum-University of Bologna, Corso d'Augusto 237, 47921 Rimini, Italy
| | - Serena Montanari
- Department for Life Quality Studies, Alma Mater Studiorum-University of Bologna, Corso d'Augusto 237, 47921 Rimini, Italy
| | - Tereza Kobrlova
- Biomedical Research Center, University Hospital, Sokolska 581, 500 05 Hradec Kralove, Czech Republic
| | - Ondrej Soukup
- Biomedical Research Center, University Hospital, Sokolska 581, 500 05 Hradec Kralove, Czech Republic
| | - Luca Valgimigli
- Department of Chemistry "G. Ciamician", Alma Mater Studiorum-University of Bologna, Via S. Giacomo 11, 40126 Bologna, Italy
| | - Vincenza Andrisano
- Department for Life Quality Studies, Alma Mater Studiorum-University of Bologna, Corso d'Augusto 237, 47921 Rimini, Italy
| | - Jeffrey W Keillor
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie-Curie, Ottawa, ON, K1N 6N5, Canada
| | - Manuela Basso
- Laboratory of Transcriptional Neurobiology, Centre for Integrative Biology, University of Trento, Via Sommarive 9, 38123 Trento, Italy
| | - Andrea Milelli
- Department for Life Quality Studies, Alma Mater Studiorum-University of Bologna, Corso d'Augusto 237, 47921 Rimini, Italy.
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1773
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Large Soluble Oligomers of Amyloid β-Protein from Alzheimer Brain Are Far Less Neuroactive Than the Smaller Oligomers to Which They Dissociate. J Neurosci 2017; 37:152-163. [PMID: 28053038 DOI: 10.1523/jneurosci.1698-16.2016] [Citation(s) in RCA: 248] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 09/30/2016] [Accepted: 11/03/2016] [Indexed: 01/02/2023] Open
Abstract
Soluble oligomers of amyloid β-protein (oAβ) isolated from the brains of Alzheimer's disease (AD) patients have been shown experimentally (in the absence of amyloid plaques) to impair hippocampal synaptic plasticity, decrease synapses, induce tau hyperphosphorylation and neuritic dystrophy, activate microglial inflammation, and impair memory in normal adult rodents. Nevertheless, there has been controversy about what types of oligomers actually confer these AD-like phenotypes. Here, we show that the vast majority of soluble Aβ species obtained from brains of humans who died with confirmed AD elute at high molecular weight (HMW) on nondenaturing size-exclusion chromatography. These species have little or no cytotoxic activity in several bioassays. However, incubation of HMW oAβ in mildly alkaline buffer led to their quantitative dissociation into low molecular weight oligomers (∼8-70 kDa), and these were now far more bioactive: they impaired hippocampal LTP, decreased neuronal levels of β2-adrenergic receptors, and activated microglia in wt mice in vivo Thus, most soluble Aβ assemblies in AD cortex are large and inactive but under certain circumstances can dissociate into smaller, highly bioactive species. Insoluble amyloid plaques likely sequester soluble HMW oligomers, limiting their potential to dissociate. We conclude that conditions that destabilize HMW oligomers or retard the sequestration of their smaller, more bioactive components are important drivers of Aβ toxicity. Selectively targeting these small, cytotoxic forms should be therapeutically beneficial. SIGNIFICANCE STATEMENT Oligomers of amyloid β-protein (oAβ) are tought to play an important role in Alzheimer's disease (AD), but there is confusion and controversy about what types and sizes of oligomers have disease-relevant activity. Using size-exclusion chromatography and three distinct measures of bioactivity, we show that the predominant forms of Aβ in aqueous extracts of AD brain are high molecular weight (HMW) and relatively inactive. Importantly, under certain conditions, the abundant HMW oAβ can dissociate into low molecular weight species, and these low molecular weight oligomers are significantly more bioactive on synapses and microglia than the HMW species from which they are derived. We conclude that conditions that destabilize HMW oAβ or retard the sequestration of smaller, more bioactive components are important drivers of Aβ toxicity.
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1774
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Abstract
Measures of the severity of cognitive impairment or parkinsonism are the usual endpoints in clinical trials for Alzheimer’s disease (AD) and Parkinson’s disease (PD), but are critically hampered by their lack of disease sensitivity and specificity. Due to the high failure rate of clinical trials, the rate of regulatory approval for efficacious new drugs has stagnated in the past few decades, with the gap between basic science discovery and clinical application metaphorically termed the “Valley of Death”. While the causes for this are probably multiple and complex, the usage of biomarkers as surrogate endpoints, particularly when they are molecularly-specific for the disease, has achieved some success in cancer trials, and it is likely that neurodegenerative disease trials would benefit from the same approach. As dementia and parkinsonism are not disease-specific clinical syndromes, both AD and PD trials have been flawed by reliance on clinical diagnosis and clinical endpoints. Clinical improvement has been a requirement for regulatory approval, but molecularly-specific biomarkers should improve both diagnostic accuracy and tracking of disease progression, allowing quicker screening of drug candidates. However, even when a molecularly-specific biomarker is found, such as amyloid imaging for AD, it may not reflect the entire extant molecular disease repertoire and may not serve equally well in the different roles of preclinical detection, diagnostic confirmation and surrogate endpoint, necessitating the usage of two, three or more biomarkers, deployed in series or in parallel.
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1775
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Abstract
Alzheimer's disease (AD) is a major form of senile dementia, characterized by progressive memory and neuronal loss combined with cognitive impairment. AD is the most common neurodegenerative disease worldwide, affecting one-fifth of those aged over 85 years. Recent therapeutic approaches have been strongly influenced by five neuropathological hallmarks of AD: acetylcholine deficiency, glutamate excitotoxicity, extracellular deposition of amyloid-β (Aβ plague), formation of intraneuronal neurofibrillary tangles (NTFs), and neuroinflammation. The lowered concentrations of acetylcholine (ACh) in AD result in a progressive and significant loss of cognitive and behavioral function. Current AD medications, memantine and acetylcholinesterase inhibitors (AChEIs) alleviate some of these symptoms by enhancing cholinergic signaling, but they are not curative. Since 2003, no new drugs have been approved for the treatment of AD. This article focuses on the current research in clinical trials targeting the neuropathological findings of AD including acetylcholine response, glutamate transmission, Aβ clearance, tau protein deposits, and neuroinflammation. These investigations include acetylcholinesterase inhibitors, agonists and antagonists of neurotransmitter receptors, β-secretase (BACE) or γ-secretase inhibitors, vaccines or antibodies targeting Aβ clearance or tau protein, as well as anti-inflammation compounds. Ongoing Phase III clinical trials via passive immunotherapy against Aβ peptides (crenezumab, gantenerumab, and aducanumab) seem to be promising. Using small molecules blocking 5-HT6 serotonin receptor (intepirdine), inhibiting BACE activity (E2609, AZD3293, and verubecestat), or reducing tau aggregation (TRx0237) are also currently in Phase III clinical trials. We here systemically review the findings from recent clinical trials to provide a comprehensive review of novel therapeutic compounds in the treatment and prevention of AD.
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Affiliation(s)
- Shih-Ya Hung
- Graduate Institute of Acupuncture Science, College of Chinese Medicine, China Medical University, Taichung, 40402 Taiwan
- Division of Colorectal Surgery, China Medical University Hospital, Taichung, 40447 Taiwan
| | - Wen-Mei Fu
- Pharmacological Institute, College of Medicine, National Taiwan University, No. 1, Sec. 1, Jen-Ai Road, Taipei, 10051 Taiwan
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1776
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1777
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Mathis CA, Lopresti BJ, Ikonomovic MD, Klunk WE. Small-molecule PET Tracers for Imaging Proteinopathies. Semin Nucl Med 2017; 47:553-575. [PMID: 28826526 DOI: 10.1053/j.semnuclmed.2017.06.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In this chapter, we provide a review of the challenges and advances in developing successful PET imaging agents for 3 major types of aggregated amyloid proteins: amyloid-beta (Aβ), tau, and alpha-synuclein (α-syn). These 3 amyloids are involved in the pathogenesis of a variety of neurodegenerative diseases, referred to as proteinopathies or proteopathies, that include Alzheimer disease, Lewy body dementias, multiple system atrophy, and frontotemporal dementias, among others. In the Introduction section, we briefly discuss the history of amyloid in neurodegenerative diseases and describe why progress in developing effective imaging agents has been hampered by the failure of crystallography to provide definitive ligand-protein interactions for rational radioligand design efforts. Instead, the field has relied on largely serendipitous, trial-and-error methods to achieve useful and specific PET amyloid imaging tracers for Aβ, tau, and α-syn deposits. Because many of the proteopathies involve more than 1 amyloid protein, it is important to develop selective PET tracers for the different amyloids to help assess the relative contribution of each to total amyloid burden. We use Pittsburgh compound B to illustrate some of the critical steps in developing a potent and selective Aβ PET imaging agent. Other selective Aβ and tau PET imaging compounds have followed similar pathways in their developmental processes. Success for selective α-syn PET imaging agents has not been realized yet, but work is ongoing in multiple laboratories throughout the world. In the tau sections, we provide background regarding 3-repeat (3R) and 4-repeat (4R) tau proteins and how they can affect the binding of tau radioligands in different tauopathies. We review the ongoing efforts to assess the properties of tau ligands, which are useful in 3R, 4R, or combined 3R-4R tauopathies. Finally, we describe in the α-syn sections recent attempts to develop selective tracers to image α-synucleinopathies.
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Affiliation(s)
- Chester A Mathis
- Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA.
| | - Brian J Lopresti
- Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Milos D Ikonomovic
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - William E Klunk
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA
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1778
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Vāvere AL, Scott PJH. Clinical Applications of Small-molecule PET Radiotracers: Current Progress and Future Outlook. Semin Nucl Med 2017; 47:429-453. [PMID: 28826519 DOI: 10.1053/j.semnuclmed.2017.05.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Radiotracers, or radiopharmaceuticals, are bioactive molecules tagged with a radionuclide used for diagnostic imaging or radiotherapy and, when a positron-emitting radionuclide is chosen, the radiotracers are used for PET imaging. The development of novel PET radiotracers in many ways parallels the development of new pharmaceuticals, and small molecules dominate research and development pipelines in both disciplines. The 4 decades since the introduction of [18F]FDG have seen the development of many small molecule PET radiotracers. Ten have been approved by the US Food and Drug Administration as of 2016, whereas hundreds more are being evaluated clinically. These radiotracers are being used in personalized medicine and to support drug discovery programs where they are greatly improving our understanding of and ability to treat diseases across many areas of medicine including neuroscience, cardiovascular medicine, and oncology.
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Affiliation(s)
- Amy L Vāvere
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN
| | - Peter J H Scott
- Department of Radiology, University of Michigan, Ann Arbor, MI.
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1779
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Abstract
A set of core cerebrospinal fluid (CSF) biomarkers for Alzheimer's disease (AD) includes total tau (T-tau), phosphorylated tau (P-tau) and β-amyloid 42 (Aβ42). These biomarkers reflect some of the key aspects of AD pathophysiology, including neuronal degeneration, tau phosphorylation with tangle formation, and Aβ aggregation with deposition of the peptide into plaques. The core AD CSF biomarkers have been validated clinically in numerous studies, and found to have a very high diagnostic performance to identify AD, both in the dementia and in the mild cognitive impairment stages of the disease. CSF Aβ42 has also been found to show very high concordance with amyloid PET to identify brain amyloid deposition. The synaptic protein neurogranin is a novel candidate CSF biomarker for AD and prodromal AD. High CSF neurogranin predicts future cognitive decline and seems to be more specific for AD than, for example, T-tau. Importantly, technical developments have given ultrasensitive measurement techniques that allow measurement of brain-specific proteins such as tau and neurofilament light (NFL) in blood samples. Both plasma tau and NFL are increased in AD, and a recent study showed that plasma NFL has a diagnostic performance comparable to the core AD CSF biomarkers, and predicted future cognitive decline. Future large longitudinal clinical studies are warranted to determine the potential for plasma tau and NFL to serve as first-in-line screening tools for neurodegeneration in primary care.
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Affiliation(s)
- Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden.
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.
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1780
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Shaw AE, Bamburg JR. Peptide regulation of cofilin activity in the CNS: A novel therapeutic approach for treatment of multiple neurological disorders. Pharmacol Ther 2017; 175:17-27. [PMID: 28232023 PMCID: PMC5466456 DOI: 10.1016/j.pharmthera.2017.02.031] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cofilin is a ubiquitous protein which cooperates with many other actin-binding proteins in regulating actin dynamics. Cofilin has essential functions in nervous system development including neuritogenesis, neurite elongation, growth cone pathfinding, dendritic spine formation, and the regulation of neurotransmission and spine function, components of synaptic plasticity essential for learning and memory. Cofilin's phosphoregulation is a downstream target of many transmembrane signaling processes, and its misregulation in neurons has been linked in rodent models to many different neurodegenerative and neurological disorders including Alzheimer disease (AD), aggression due to neonatal isolation, autism, manic/bipolar disorder, and sleep deprivation. Cognitive and behavioral deficits of these rodent models have been largely abrogated by modulation of cofilin activity using viral-mediated, genetic, and/or small molecule or peptide therapeutic approaches. Neuropathic pain in rats from sciatic nerve compression has also been reduced by modulating the cofilin pathway within neurons of the dorsal root ganglia. Neuroinflammation, which occurs following cerebral ischemia/reperfusion, but which also accompanies many other neurodegenerative syndromes, is markedly reduced by peptides targeting specific chemokine receptors, which also modulate cofilin activity. Thus, peptide therapeutics offer potential for cost-effective treatment of a wide variety of neurological disorders. Here we discuss some recent results from rodent models using therapeutic peptides with a surprising ability to cross the rodent blood brain barrier and alter cofilin activity in brain. We also offer suggestions as to how neuronal-specific cofilin regulation might be achieved.
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Affiliation(s)
- Alisa E Shaw
- Department of Biochemistry and Molecular Biology, Molecular, Cellular and Integrative Neuroscience Program, Colorado State University, Fort Collins, CO 80523-1870, United States
| | - James R Bamburg
- Department of Biochemistry and Molecular Biology, Molecular, Cellular and Integrative Neuroscience Program, Colorado State University, Fort Collins, CO 80523-1870, United States.
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1781
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Xia C, Dickerson BC. Multimodal PET Imaging of Amyloid and Tau Pathology in Alzheimer Disease and Non-Alzheimer Disease Dementias. PET Clin 2017; 12:351-359. [PMID: 28576172 PMCID: PMC5690983 DOI: 10.1016/j.cpet.2017.02.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Biomarkers of the molecular pathology underpinning dementia syndromes are increasingly recognized as crucial for diagnosis and development of disease-modifying treatments. Amyloid PET imaging is an integral part of the diagnostic assessment of Alzheimer disease. Its use has also deepened understanding of the role of amyloid pathology in Lewy body disorders and aging. Tau PET imaging is an imaging biomarker that will likely play an important role in the diagnosis, monitoring, and treatment in dementias. Using tau PET imaging to examine how tau pathology relates to amyloid and other markers of neurodegeneration will serve to better understand the pathophysiologic cascade that leads to dementia.
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Affiliation(s)
- Chenjie Xia
- Department of Neurology, Jewish General Hospital, McGill University, 3755 Chemin de la Côte-Sainte-Catherine Road, Suite E-005, Montreal, QC H3T 1E2, Canada
| | - Bradford C Dickerson
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital, Harvard University, 149 13th Street, Suite 2691, Charlestown, Boston, MA 02129, USA.
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1782
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Chen YH, Lo RY. Alzheimer's disease and osteoporosis. Tzu Chi Med J 2017; 29:138-142. [PMID: 28974906 PMCID: PMC5615992 DOI: 10.4103/tcmj.tcmj_54_17] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 03/13/2017] [Accepted: 03/13/2017] [Indexed: 12/27/2022] Open
Abstract
Alzheimer's disease (AD) and osteoporosis are both common degenerative diseases in the elderly population. The incidence of both diseases increases with age and will be posing enormous societal burden worldwide. It may appear that AD and osteoporosis are two distinct diseases although many risk factors are shared. Previous observational studies have shown that patients with osteoporosis have higher risks of developing AD than those who do not have osteoporosis. Although osteoporosis, falls, and fractures are more often seen in patients with AD than other older adults, the association between these two diseases may be due to a pathophysiological link rather than one condition causing the other. Several in vitro and in vivo studies lend support to this notion. Patients with AD have excessive amyloid plaques in the brain, and the pathology may extend to peripheral organs and cause skeletal amyloid deposition, which would enhance receptor activator nuclear factor-kappa B ligand signaling and lead to greater osteoclast activities. Patients with osteoporosis may have Vitamin D deficiency or lower levels of Vitamin D binding protein, which protects against amyloid aggregation, thus linking Vitamin D deficiency and AD or osteoporosis and AD. Osteoporosis coexisting with AD provides a window to examine the amyloid hypothesis from peripheral tissues. Future studies are warranted to clarify the role of genetic background regarding Vitamin D levels, exposure to sunlight, estrogen replacement therapy, and physical activity in patients with both chronic diseases.
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Affiliation(s)
- Yu-Hung Chen
- Department of Nuclear Medicine, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
| | - Raymond Y. Lo
- Department of Neurology, Memory and Aging Center, Buddhist Tzu Chi General Hospital and Tzu Chi University, Hualien, Taiwan
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1783
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Shrivastava AN, Aperia A, Melki R, Triller A. Physico-Pathologic Mechanisms Involved in Neurodegeneration: Misfolded Protein-Plasma Membrane Interactions. Neuron 2017; 95:33-50. [DOI: 10.1016/j.neuron.2017.05.026] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 05/12/2017] [Accepted: 05/19/2017] [Indexed: 12/12/2022]
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1784
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Cabral CM, McGovern KE, MacDonald WR, Franco J, Koshy AA. Dissecting Amyloid Beta Deposition Using Distinct Strains of the Neurotropic Parasite Toxoplasma gondii as a Novel Tool. ASN Neuro 2017; 9:1759091417724915. [PMID: 28817954 PMCID: PMC5565021 DOI: 10.1177/1759091417724915] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 06/29/2017] [Accepted: 06/29/2017] [Indexed: 01/13/2023] Open
Abstract
Genetic and pathologic data suggest that amyloid beta (Aβ), produced by processing of the amyloid precursor protein, is a major initiator of Alzheimer's disease (AD). To gain new insights into Aβ modulation, we sought to harness the power of the coevolution between the neurotropic parasite Toxoplasma gondii and the mammalian brain. Two prior studies attributed Toxoplasma-associated protection against Aβ to increases in anti-inflammatory cytokines (TGF-β and IL-10) and infiltrating phagocytic monocytes. These studies only used one Toxoplasma strain making it difficult to determine if the noted changes were associated with Aβ protection or simply infection. To address this limitation, we infected a third human amyloid precursor protein AD mouse model (J20) with each of the genetically distinct, canonical strains of Toxoplasma (Type I, Type II, or Type III). We then evaluated the central nervous system (CNS) for Aβ deposition, immune cell responses, global cytokine environment, and parasite burden. We found that only Type II infection was protective against Aβ deposition despite both Type II and Type III strains establishing a chronic CNS infection and inflammatory response. Compared with uninfected and Type I-infected mice, both Type II- and Type III-infected mice showed increased numbers of CNS T cells and microglia and elevated pro-inflammatory cytokines, but neither group showed a >2-fold elevation of TGF-β or IL-10. These data suggest that we can now use our identification of protective (Type II) and nonprotective (Type III) Toxoplasma strains to determine what parasite and host factors are linked to decreased Aβ burden rather than simply with infection.
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Affiliation(s)
| | | | - Wes R. MacDonald
- Undergraduate Biology Research Program, University of Arizona, Tucson, AZ, USA
| | - Jenna Franco
- BIO5 Institute, University of Arizona, Tucson, AZ, USA
| | - Anita A. Koshy
- BIO5 Institute, University of Arizona, Tucson, AZ, USA
- Department of Immunobiology, University of Arizona, Tucson, AZ, USA
- Department of Neurology, University of Arizona, Tucson, AZ, USA
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1785
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Chemerovski‐Glikman M, Frenkel‐Pinter M, Mdah R, Abu‐Mokh A, Gazit E, Segal D. Inhibition of the Aggregation and Toxicity of the Minimal Amyloidogenic Fragment of Tau by Its Pro‐Substituted Analogues. Chemistry 2017; 23:9618-9624. [DOI: 10.1002/chem.201701218] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Indexed: 12/15/2022]
Affiliation(s)
- Marina Chemerovski‐Glikman
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
| | - Moran Frenkel‐Pinter
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
| | - Ragad Mdah
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
| | - Amjaad Abu‐Mokh
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
| | - Ehud Gazit
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
- Department of Materials Science and EngineeringIby and Aladar Fleischman Faculty of EngineeringTel Aviv University Tel Aviv 6997801 Israel
| | - Daniel Segal
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
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1786
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Heurling K, Leuzy A, Jonasson M, Frick A, Zimmer ER, Nordberg A, Lubberink M. Quantitative positron emission tomography in brain research. Brain Res 2017; 1670:220-234. [PMID: 28652218 DOI: 10.1016/j.brainres.2017.06.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/19/2017] [Accepted: 06/20/2017] [Indexed: 12/21/2022]
Abstract
The application of positron emission tomography (PET) in brain research has increased substantially during the past 20years, and is still growing. PET provides a unique insight into physiological and pathological processes in vivo. In this article we introduce the fundamentals of PET, and the methods available for acquiring quantitative estimates of the parameters of interest. A short introduction to different areas of application is also given, including basic research of brain function and in neurology, psychiatry, drug receptor occupancy studies, and its application in diagnostics of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Our aim is to inform the unfamiliar reader of the underlying basics and potential applications of PET, hoping to inspire the reader into considering how the technique could be of benefit for his or her own research.
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Affiliation(s)
- Kerstin Heurling
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Sweden; Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
| | - Antoine Leuzy
- Department Neurobiology, Care Sciences and Society, Division of Translational Alzheimer Neurobiology, Karolinska Institutet, Stockholm, Sweden
| | - My Jonasson
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; Medical Physics, Uppsala University Hospital, Uppsala, Sweden
| | - Andreas Frick
- Department of Psychology, Uppsala University, Uppsala, Sweden; Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Eduardo R Zimmer
- Department of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil; Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Agneta Nordberg
- Department Neurobiology, Care Sciences and Society, Division of Translational Alzheimer Neurobiology, Karolinska Institutet, Stockholm, Sweden; Department of Geriatric Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Mark Lubberink
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; Medical Physics, Uppsala University Hospital, Uppsala, Sweden
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1787
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Sevigny J, Chiao P, Bussière T, Weinreb PH, Williams L, Maier M, Dunstan R, Salloway S, Chen T, Ling Y, O’Gorman J, Qian F, Arastu M, Li M, Chollate S, Brennan MS, Quintero-Monzon O, Scannevin RH, Arnold HM, Engber T, Rhodes K, Ferrero J, Hang Y, Mikulskis A, Grimm J, Hock C, Nitsch RM, Sandrock A. Addendum: The antibody aducanumab reduces Aβ plaques in Alzheimer’s disease. Nature 2017. [DOI: 10.1038/nature22809] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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1788
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Doens D, Valiente PA, Mfuh AM, X. T. Vo A, Tristan A, Carreño L, Quijada M, Nguyen VT, Perry G, Larionov OV, Lleonart R, Fernández PL. Identification of Inhibitors of CD36-Amyloid Beta Binding as Potential Agents for Alzheimer's Disease. ACS Chem Neurosci 2017; 8:1232-1241. [PMID: 28150942 DOI: 10.1021/acschemneuro.6b00386] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Neuroinflammation is one of the hallmarks of Alzheimer's disease pathology. Amyloid β has a central role in microglia activation and the subsequent secretion of inflammatory mediators that are associated with neuronal toxicity. The recognition of amyloid β by microglia depends on the expression of several receptors implicated in the clearance of amyloid and in cell activation. CD36 receptor expressed on microglia interacts with fibrils of amyloid inducing the release of proinflammatory cytokines and amyloid internalization. The interruption of the interaction CD36-amyloid β compromises the activation of microglia cells. We have developed and validated a new colorimetric assay to identify potential inhibitors of the binding of amyloid β to CD36. We have found seven molecules, structural analogues of the Trichodermamide family of natural products that interfere with the interaction CD36-amyloid β. By combining molecular docking and dynamics simulations, we suggested the second fatty acids binding site within the large luminal hydrophobic tunnel, present in the extracellular domain of CD36, as the binding pocket of these compounds. Free energy calculations predicted the nonpolar component as the driving force for the binding of these inhibitors. These molecules also inhibited the production of TNF-α, IL-6, and IL-1β by peritoneal macrophages stimulated with fibrils of amyloid β. This work serves as a platform for the identification of new potential anti-inflammatory agents for the treatment of Alzheimer's disease.
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Affiliation(s)
- Deborah Doens
- Centro de Biología Molecular y Celular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge #219, Panama City, 0843-01103 Panama
- Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur, Andhra Pradesh 522510, India
| | - Pedro A. Valiente
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, La Habana, Cuba
| | | | | | - Adilia Tristan
- Centro de Biología Molecular y Celular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge #219, Panama City, 0843-01103 Panama
| | - Lizmar Carreño
- Centro de Biología Molecular y Celular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge #219, Panama City, 0843-01103 Panama
| | - Mario Quijada
- Centro de Biología Molecular y Celular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge #219, Panama City, 0843-01103 Panama
| | | | | | | | - Ricardo Lleonart
- Centro de Biología Molecular y Celular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge #219, Panama City, 0843-01103 Panama
| | - Patricia L. Fernández
- Centro de Biología Molecular y Celular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge #219, Panama City, 0843-01103 Panama
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1789
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Valls-Comamala V, Guivernau B, Bonet J, Puig M, Perálvarez-Marín A, Palomer E, Fernàndez-Busquets X, Altafaj X, Tajes M, Puig-Pijoan A, Vicente R, Oliva B, Muñoz FJ. The antigen-binding fragment of human gamma immunoglobulin prevents amyloid β-peptide folding into β-sheet to form oligomers. Oncotarget 2017; 8:41154-41165. [PMID: 28467807 PMCID: PMC5522293 DOI: 10.18632/oncotarget.17074] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 03/22/2017] [Indexed: 02/05/2023] Open
Abstract
The amyloid beta-peptide (Aβ) plays a leading role in Alzheimer's disease (AD) physiopathology. Even though monomeric forms of Aβ are harmless to cells, Aβ can aggregate into β-sheet oligomers and fibrils, which are both neurotoxic. Therefore, one of the main therapeutic approaches to cure or delay AD onset and progression is targeting Aβ aggregation. In the present study, we show that a pool of human gamma immunoglobulins (IgG) protected cortical neurons from the challenge with Aβ oligomers, as assayed by MTT reduction, caspase-3 activation and cytoskeleton integrity. In addition, we report the inhibitory effect of IgG on Aβ aggregation, as shown by Thioflavin T assay, size exclusion chromatography and atomic force microscopy. Similar results were obtained with Palivizumab, a human anti-sincitial virus antibody. In order to dissect the important domains, we cleaved the pool of human IgG with papain to obtain Fab and Fc fragments. Using these cleaved fragments, we functionally identified Fab as the immunoglobulin fragment inhibiting Aβ aggregation, a result that was further confirmed by an in silico structural model. Interestingly, bioinformatic tools show a highly conserved structure able to bind amyloid in the Fab region. Overall, our data strongly support the inhibitory effect of human IgG on Aβ aggregation and its neuroprotective role.
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Affiliation(s)
- Victòria Valls-Comamala
- Laboratory of Molecular Physiology, Faculty of Health and Life Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Biuse Guivernau
- Laboratory of Molecular Physiology, Faculty of Health and Life Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Jaume Bonet
- Laboratory of Structural Bioinformatics (GRIB), Faculty of Health and Life Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Marta Puig
- Laboratory of Molecular Physiology, Faculty of Health and Life Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Alex Perálvarez-Marín
- Unitat de Biofísica, Departament de Bioquímica i de Biologia Molecular, Facultat de Medicina, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Ernest Palomer
- Laboratory of Molecular Physiology, Faculty of Health and Life Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Xavier Fernàndez-Busquets
- Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Xavier Altafaj
- Bellvitge Biomedical Research Institute (IDIBELL) - Unit of Neuropharmacology and Pain, University of Barcelona, Barcelona, Spain
| | - Marta Tajes
- Heart Diseases Biomedical Research Group, IMIM-Hospital del Mar Medical Research Institute, Barcelona, Spain
| | - Albert Puig-Pijoan
- Servei de Neurologia, Hospital del Mar-IMIM-Parc de Salut Mar, Barcelona, Spain
| | - Rubén Vicente
- Laboratory of Molecular Physiology, Faculty of Health and Life Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Baldomero Oliva
- Laboratory of Structural Bioinformatics (GRIB), Faculty of Health and Life Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Francisco J. Muñoz
- Laboratory of Molecular Physiology, Faculty of Health and Life Sciences, Universitat Pompeu Fabra, Barcelona, Spain
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1790
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Olsson B, Schott JM, Blennow K, Zetterberg H. The use of cerebrospinal fluid biomarkers to measure change in neurodegeneration in Alzheimer’s disease clinical trials. Expert Rev Neurother 2017; 17:767-775. [DOI: 10.1080/14737175.2017.1341311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Bob Olsson
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
| | - Jonathan M. Schott
- Dementia Research Centre, Institute of Neurology, University College London, London, UK
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, United Kingdom
- UK Dementia Research Institute, London, UK
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1791
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Schulz JB, Cookson MR, Hausmann L. The impact of fraudulent and irreproducible data to the translational research crisis - solutions and implementation. J Neurochem 2017; 139 Suppl 2:253-270. [PMID: 27797406 DOI: 10.1111/jnc.13844] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 09/12/2016] [Accepted: 09/13/2016] [Indexed: 12/14/2022]
Abstract
One of the aims of basic neuroscience research is ultimately the development of therapeutics to cure diseases. Funders granting money to research institutions increasingly express interest into how their financial resources are used and look for successful translation in clinical practice. Disappointingly, many findings that started out promising in basic research projects and phase I trials did not live up to the promise of therapeutic efficacy in later phase II or III trials. An inordinately high amount of time and money is thus spent on research that does not always have the required human impact. Potential reasons for these problems are numerous. Although research misconduct occurs and contributes to this shortcoming, it is not the only important factor. Frequently, basic science results turn out to be irreproducible. Irreproducibility, outside of malfeasance, is multifactorial and can include poor experimental design, conduct, statistical analysis, reporting standards, and conceptual flaws. Further confounding problems include an insufficient transferability of animal to human physiology, as well as intersubject group variability, for example, sexual dimorphisms. While the causes of poor data reproducibility are therefore numerous, equally there are many groups that can contribute to improvements in how basic science is reported. Here, we will review how the Journal of Neurochemistry can contribute to increasing the value of preclinical and translational research. Despite a vast amount of very promising basic research findings, these failed to successfully translate into the clinical practice so far. The reasons for this 'data reproducibility crisis' are numerous, for example, rooting in insufficient experimental design, conceptual flaws, incorrect statistical planning and evaluation, incomplete model system that do not adequately reproduce the human physiology, and further reasons discussed in this Review with the aim to present practical solutions that can be implemented by researchers, journals editors, and reviewers. We will also explain measures the Journal of Neurochemistry have implemented to overcome these issues and weaknesses in preclinical research. These includes adherence to the ARRIVE ( www.nc3rs.org) guidelines, NINDS standards (doi: 10.1038/nature11556), and The Transparency and Openness Promotion Guidelines (TOP) Committee guidelines (https://cos.io/top/#TOP). This article is part of the 60th Anniversary special issue.
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Affiliation(s)
- Jörg B Schulz
- Department of Neurology, University Hospital, RWTH Aachen, Aachen, Germany. .,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging, Forschungszentrum Jülich GmbH and RWTH Aachen University, Aachen, Germany.
| | - Mark R Cookson
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Laura Hausmann
- Department of Neurology, University Hospital, RWTH Aachen, Aachen, Germany
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1792
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Abstract
BACKGROUND Drug delivery to the brain is a major roadblock to treatment of Alzheimer's disease. Recent results of the PRIME study indicate that increasing brain penetration of antibody drugs improves Alzheimer's treatment outcomes. New approaches are needed to better accomplish this goal. Based on prior evidence, the hypothesis that glycan modification alters antibody blood-brain barrier permeability was tested here. METHODS The blood-brain barrier permeability coefficient Pe of different glycosylated states of anti-amyloid IgG was measured using in vitro models of brain microvascular endothelial cells. Monoclonal antibodies 4G8, with sialic acid, and 6E10, lacking sialic acid, were studied. The amount of sialic acid was determined using quantitative and semi-quantitative surface plasmon resonance methods. RESULTS Influx of IgG was not saturable and was largely insensitive to IgG species and glycosylation state. By contrast, efflux of 4G8 efflux was significantly lower than both albumin controls and 6E10. Removal of α2,6-linked sialic acid group present on 12% of 4G8 completely restored efflux to that of 6E10 but increasing the α2,6-sialylated fraction to 15% resulted in no change. Removal of the Fc glycan from 4G8 partially restored efflux. Alternate sialic acid groups with α2,3 and α2,8 linkages, nor on the Fc glycan, were not detected at significant levels on either 4G8 or 6E10. CONCLUSIONS These results support a model in which surface-sialylated 4G8 inhibits its own efflux and that of asialylated 4G8. GENERAL SIGNIFICANCE Glycan modification has the potential to increase antibody drug penetration into the brain through efflux inhibition.
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1793
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Kikuchi K, Kidana K, Tatebe T, Tomita T. Dysregulated Metabolism of the Amyloid‐β Protein and Therapeutic Approaches in Alzheimer Disease. J Cell Biochem 2017; 118:4183-4190. [DOI: 10.1002/jcb.26129] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 05/08/2017] [Indexed: 12/31/2022]
Affiliation(s)
- Kazunori Kikuchi
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical SciencesThe University of TokyoTokyoJapan
| | - Kiwami Kidana
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical SciencesThe University of TokyoTokyoJapan
| | - Takuya Tatebe
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical SciencesThe University of TokyoTokyoJapan
| | - Taisuke Tomita
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical SciencesThe University of TokyoTokyoJapan
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1794
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Landen JW, Andreasen N, Cronenberger CL, Schwartz PF, Börjesson-Hanson A, Östlund H, Sattler CA, Binneman B, Bednar MM. Ponezumab in mild-to-moderate Alzheimer's disease: Randomized phase II PET-PIB study. ALZHEIMERS & DEMENTIA-TRANSLATIONAL RESEARCH & CLINICAL INTERVENTIONS 2017; 3:393-401. [PMID: 29067345 PMCID: PMC5651442 DOI: 10.1016/j.trci.2017.05.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
INTRODUCTION The safety, pharmacokinetics, and effect on peripheral and central amyloid β (Aβ) of multiple doses of ponezumab, an anti-Aβ monoclonal antibody, were characterized in subjects with mild-to-moderate Alzheimer's disease treated for 1 year. METHODS Subjects were aged ≥50 years with Mini-Mental State Examination scores 16 to 26. Cohort Q was randomized to ponezumab 10 mg/kg (n = 12) or placebo (n = 6) quarterly. Cohort M was randomized to a loading dose of ponezumab 10 mg/kg or placebo, followed by monthly ponezumab 7.5 mg/kg (n = 12) or placebo (n = 6), respectively. RESULTS Ponezumab was generally well tolerated. Plasma concentrations increased dose dependently, but cerebrospinal fluid (CSF) penetration was low. Plasma Aβ increased dose dependently with ponezumab, but CSF biomarkers, brain amyloid burden, cognition, and function were not affected. CONCLUSIONS Both ponezumab dosing schedules were generally safe and well tolerated but did not alter CSF biomarkers, brain amyloid burden, or clinical outcomes.
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1795
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Wang SW, Liu DQ, Zhang LX, Ji M, Zhang YX, Dong QX, Liu SY, Xie XX, Liu RT. A vaccine with Aβ oligomer-specific mimotope attenuates cognitive deficits and brain pathologies in transgenic mice with Alzheimer's disease. ALZHEIMERS RESEARCH & THERAPY 2017; 9:41. [PMID: 28592267 PMCID: PMC5461751 DOI: 10.1186/s13195-017-0267-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 05/22/2017] [Indexed: 12/22/2022]
Abstract
Background β-Amyloid peptide (Aβ) oligomers are initial factors used to induce Alzheimer’s disease (AD) development, and Aβ monomers have normal physiological function. The antibodies or vaccines against Aβ monomers have serious problems, such as side effects and low curative effects. Therefore, it is essential to specifically target Aβ oligomers rather than monomers for the treatment of AD. Methods The mimotopes of Aβ oligomers were obtained by panning the phage-displayed random peptide libraries using oligomer-specific antibodies as targets and expressed on the surface of EBY100 Saccharomyces cerevisiae to generate yeast cell base vaccines. One vaccine (AOE1) induced antibodies specifically against Aβ oligomers and was selected for further study. The APP/PS1 mice were subcutaneously immunized with AOE1 eight times. The levels and characteristics of antibodies induced by AOE1 were determined by enzyme-linked immunosorbent assay. The effect of AOE1 on the cognitive deficits of AD mice was tested by novel object recognition (NOR) and Y-maze. Dot blot analysis, Western blot analysis, and immunohistochemistry were applied to measure the effects of AOE1 on Aβ pathologies, neuroinflammation, and microhemorrhages in the brains of AD mice. Results Eight mimotope candidates of Aβ oligomers were selected and expressed on EBY100 S. cerevisiae. Only AOE1 vaccine containing mimotope L2 induced antibodies that specifically recognized Aβ42 oligomers rather than monomers. AOE1 immunization significantly increased the AD mice’s exploration times for the novel object in the NOR test and the choices for new arms in the Y-maze test, and it reduced levels of Aβ oligomers and glial activation in the AD mouse brains. No activation of Aβ-specific T cells and microhemorrhages was observed in their brains following AOE1 vaccination. Conclusions AOE1 is the first vaccine applying the oligomer-specific mimotope as an immunogen, which could induce antibodies with high specificity to Aβ oligomers. AOE1 immunization attenuated Aβ pathologies and cognitive deficits in AD mice, decreased the overactivation of glial cells, and did not induce microhemorrhage in the brains of AD mice. These findings suggest that AOE1 may be a safer and more effective vaccine for AD treatment.
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Affiliation(s)
- Shao-Wei Wang
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing, 100190, China
| | - Dong-Qun Liu
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing, 100190, China
| | - Ling-Xiao Zhang
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing, 100190, China
| | - Mei Ji
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing, 100190, China
| | - Yang-Xin Zhang
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing, 100190, China.,School of Life Science, Anhui Agricultural University, Hefei, 230036, China
| | - Quan-Xiu Dong
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing, 100190, China
| | - Shu-Ying Liu
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing, 100190, China.,School of Life Science, Ningxia University, Yinchuan, 750021, China
| | - Xi-Xiu Xie
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing, 100190, China
| | - Rui-Tian Liu
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing, 100190, China.
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1796
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Phage display and kinetic selection of antibodies that specifically inhibit amyloid self-replication. Proc Natl Acad Sci U S A 2017; 114:6444-6449. [PMID: 28584111 DOI: 10.1073/pnas.1700407114] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The aggregation of the amyloid β peptide (Aβ) into amyloid fibrils is a defining characteristic of Alzheimer's disease. Because of the complexity of this aggregation process, effective therapeutic inhibitors will need to target the specific microscopic steps that lead to the production of neurotoxic species. We introduce a strategy for generating fibril-specific antibodies that selectively suppress fibril-dependent secondary nucleation of the 42-residue form of Aβ (Aβ42). We target this step because it has been shown to produce the majority of neurotoxic species during aggregation of Aβ42. Starting from large phage display libraries of single-chain antibody fragments (scFvs), the three-stage approach that we describe includes (i) selection of scFvs with high affinity for Aβ42 fibrils after removal of scFvs that bind Aβ42 in its monomeric form; (ii) ranking, by surface plasmon resonance affinity measurements, of the resulting candidate scFvs that bind to the Aβ42 fibrils; and (iii) kinetic screening and analysis to find the scFvs that inhibit selectively the fibril-catalyzed secondary nucleation process in Aβ42 aggregation. By applying this approach, we have identified four scFvs that inhibit specifically the fibril-dependent secondary nucleation process. Our method also makes it possible to discard antibodies that inhibit elongation, an important factor because the suppression of elongation does not target directly the production of toxic oligomers and may even lead to its increase. On the basis of our results, we suggest that the method described here could form the basis for rationally designed immunotherapy strategies to combat Alzheimer's and related neurodegenerative diseases.
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1797
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Aprile FA, Sormanni P, Perni M, Arosio P, Linse S, Knowles TPJ, Dobson CM, Vendruscolo M. Selective targeting of primary and secondary nucleation pathways in Aβ42 aggregation using a rational antibody scanning method. SCIENCE ADVANCES 2017; 3:e1700488. [PMID: 28691099 PMCID: PMC5479649 DOI: 10.1126/sciadv.1700488] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 04/26/2017] [Indexed: 05/19/2023]
Abstract
Antibodies targeting Aβ42 are under intense scrutiny because of their therapeutic potential for Alzheimer's disease. To enable systematic searches, we present an "antibody scanning" strategy for the generation of a panel of antibodies against Aβ42. Each antibody in the panel is rationally designed to target a specific linear epitope, with the selected epitopes scanning the Aβ42 sequence. By screening in vitro the panel to identify the specific microscopic steps in the Aβ42 aggregation process influenced by each antibody, we identify two antibodies that target specifically the primary and the secondary nucleation steps, which are key for the production of Aβ42 oligomers. These two antibodies act, respectively, to delay the onset of aggregation and to block the proliferation of aggregates, and correspondingly reduce the toxicity in a Caenorhabditis elegans model overexpressing Aβ42. These results illustrate how the antibody scanning method described here can be used to readily obtain very small antibody libraries with extensive coverage of the sequences of target proteins.
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Affiliation(s)
- Francesco A. Aprile
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Pietro Sormanni
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Michele Perni
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Paolo Arosio
- Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
| | - Sara Linse
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Tuomas P. J. Knowles
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Christopher M. Dobson
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
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1798
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Caselli RJ, Beach TG, Knopman DS, Graff-Radford NR. Alzheimer Disease: Scientific Breakthroughs and Translational Challenges. Mayo Clin Proc 2017; 92:978-994. [PMID: 28578785 PMCID: PMC5536337 DOI: 10.1016/j.mayocp.2017.02.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 01/17/2017] [Accepted: 02/13/2017] [Indexed: 01/13/2023]
Abstract
Alzheimer disease (AD) was originally conceived as a rare disease that caused presenile dementia but has come to be understood as the most prevalent cause of dementia at any age worldwide. It has an extended preclinical phase characterized by sequential changes in imaging and cerebrospinal fluid biomarkers with subtle memory decline beginning more than a decade before the emergence of symptomatic memory loss heralding the beginning of the mild cognitive impairment stage. The apolipoprotein E ε4 allele is a prevalent and potent risk factor for AD that has facilitated research into its preclinical phase. Cerebral Aβ levels build from preclinical through early dementia stages followed by hyperphosphorylated tau-related pathology, the latter driving cognitive deficits and dementia severity. Structural and molecular imaging can now recapitulate the neuropathology of AD antemortem. Autosomal dominant forms of early-onset familial AD gave rise to the amyloid hypothesis of AD, which, in turn, has led to therapeutic trials of immunotherapy designed to clear cerebral amyloid, but to date results have been disappointing. Genome-wide association studies have identified multiple additional risk factors, but to date none have yielded an effective alternate therapeutic target. Current and future trials aimed at presymptomatic individuals either harboring cerebral amyloid or at genetically high risk offer the hope that earlier intervention might yet succeed where trials in patients with established dementia have failed. A major looming challenge will be that of expensive, incompletely effective disease-modifying therapy: who and when to treat, and how to pay for it.
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Affiliation(s)
| | - Thomas G Beach
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ
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1799
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Alzheimer's disease drug development pipeline: 2017. ALZHEIMERS & DEMENTIA-TRANSLATIONAL RESEARCH & CLINICAL INTERVENTIONS 2017; 3:367-384. [PMID: 29067343 PMCID: PMC5651419 DOI: 10.1016/j.trci.2017.05.002] [Citation(s) in RCA: 275] [Impact Index Per Article: 39.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
INTRODUCTION There is an urgent need to develop new treatments for Alzheimer's disease (AD) and to understand the drug development process for new AD therapies. METHODS We assessed the agents in the AD pipeline as documented in clinicaltrials.gov for phase I, phase II, and phase III, accessed 1/5/2017. RESULTS There are 105 agents in the AD treatment development pipeline, of which 25 agents are in 29 trials in phase I, 52 agents are in 68 trials in phase II, and 28 agents are in 42 trials in phase III. Seventy percent of drugs in the AD pipeline are disease-modifying therapies (DMTs). Fourteen percent are symptomatic cognitive enhancers, and 13% are symptomatic agents addressing neuropsychiatric and behavioral changes (2% have undisclosed mechanisms). Most trials are sponsored by the biopharmaceutical industry. Trials include patients with preclinical AD (cognitively normal with biomarker evidence of AD), prodromal AD (mild cognitive symptoms and biomarker evidence of AD), and AD dementia. Biomarkers are included in many drug development programs particularly those for DMTs. Thirteen of 46 phase II DMT trials have amyloid imaging as an entry criterion, and 10 of 28 phase III trials incorporate amyloid imaging for diagnosis and entry. A large number of participants are needed for AD clinical trials; in total, 54,073 participants are required for trials spanning preclinical AD to AD dementia. When compared with the 2016 pipeline, there are eight new agents in phase I, 16 in phase II, and five in phase III. DISCUSSION The AD drug development pipeline has 105 agents divided among phase I, phase II, and phase III. The trials include a wide range of clinical trial populations, many mechanisms of action, and require a substantial number of clinical trial participants. Biomarkers are increasingly used in patient identification and as outcome measures, particularly in trials of DMTs.
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1800
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Mechanisms of vascular disease in dementia: what does industry want to know? Clin Sci (Lond) 2017; 131:799-802. [PMID: 28424374 DOI: 10.1042/cs20160724] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/06/2017] [Accepted: 02/09/2017] [Indexed: 11/17/2022]
Abstract
Despite recent advances in basic and clinical science, dementia remains an area of high unmet medical need. The role of cerebrovascular mechanisms in the pathogenesis and progression of cognitive and functional impairment in dementia is being revived. In order to facilitate the development of therapeutic approaches, it is critical that a number of fundamental elements are integrated into research strategies investigating cerebrovascular pathologies as these will maximize the opportunity of bringing medicines to patients in a timely manner.
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