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Sarabia-Vallejo Á, López-Alvarado P, Menéndez JC. Small-molecule theranostics in Alzheimer's disease. Eur J Med Chem 2023; 255:115382. [PMID: 37141706 DOI: 10.1016/j.ejmech.2023.115382] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/12/2023] [Accepted: 04/14/2023] [Indexed: 05/06/2023]
Abstract
Alzheimer's Disease (AD) remains one of the most challenging health-related issues for our society. It is becoming increasingly prevalent, especially in developed countries, due to the rising life expectancy and, moreover, represents a considerable economic burden worldwide. All efforts at the discovery of new diagnostic and therapeutic tools in the last decades have invariably met with failure, making AD an incurable illness and underscoring the need for new approaches. In recent years, theranostic agents have emerged as an interesting strategy. They are molecules able to simultaneously provide diagnostic information and deliver therapeutic activity, allowing for the assessment of the molecule activity, the organism response and the pharmacokinetics. This makes these compounds promising for streamlining research on AD drugs and for their application in personalized medicine. We review here the field of small-molecule theranostic agents as promising tools for the development of novel diagnostic and therapeutic resources against AD, highlighting the positive and significant impact that theranostics can be expected to have in the near future in clinical practice.
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Affiliation(s)
- Álvaro Sarabia-Vallejo
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, 28040, Madrid, Spain
| | - Pilar López-Alvarado
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, 28040, Madrid, Spain
| | - J Carlos Menéndez
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, 28040, Madrid, Spain.
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52
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Grochowska KM, Gomes GM, Raman R, Kaushik R, Sosulina L, Kaneko H, Oelschlegel AM, Yuanxiang P, Reyes‐Resina I, Bayraktar G, Samer S, Spilker C, Woo MS, Morawski M, Goldschmidt J, Friese MA, Rossner S, Navarro G, Remy S, Reissner C, Karpova A, Kreutz MR. Jacob-induced transcriptional inactivation of CREB promotes Aβ-induced synapse loss in Alzheimer's disease. EMBO J 2023; 42:e112453. [PMID: 36594364 PMCID: PMC9929644 DOI: 10.15252/embj.2022112453] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 12/07/2022] [Accepted: 12/09/2022] [Indexed: 01/04/2023] Open
Abstract
Synaptic dysfunction caused by soluble β-amyloid peptide (Aβ) is a hallmark of early-stage Alzheimer's disease (AD), and is tightly linked to cognitive decline. By yet unknown mechanisms, Aβ suppresses the transcriptional activity of cAMP-responsive element-binding protein (CREB), a master regulator of cell survival and plasticity-related gene expression. Here, we report that Aβ elicits nucleocytoplasmic trafficking of Jacob, a protein that connects a NMDA-receptor-derived signalosome to CREB, in AD patient brains and mouse hippocampal neurons. Aβ-regulated trafficking of Jacob induces transcriptional inactivation of CREB leading to impairment and loss of synapses in mouse models of AD. The small chemical compound Nitarsone selectively hinders the assembly of a Jacob/LIM-only 4 (LMO4)/ Protein phosphatase 1 (PP1) signalosome and thereby restores CREB transcriptional activity. Nitarsone prevents impairment of synaptic plasticity as well as cognitive decline in mouse models of AD. Collectively, the data suggest targeting Jacob protein-induced CREB shutoff as a therapeutic avenue against early synaptic dysfunction in AD.
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Affiliation(s)
- Katarzyna M Grochowska
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
- Leibniz Group ‘Dendritic Organelles and Synaptic Function’, Center for Molecular Neurobiology (ZMNH)University Medical Center Hamburg‐EppendorfHamburgGermany
| | - Guilherme M Gomes
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
- Center for Behavioral Brain SciencesOtto von Guericke UniversityMagdeburgGermany
| | - Rajeev Raman
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Rahul Kaushik
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Liudmila Sosulina
- Department of Cellular NeuroscienceLeibniz Institute for NeurobiologyMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
| | - Hiroshi Kaneko
- Department of Cellular NeuroscienceLeibniz Institute for NeurobiologyMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
| | | | - PingAn Yuanxiang
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | | | - Gonca Bayraktar
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Sebastian Samer
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Christina Spilker
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Marcel S Woo
- Institute of Neuroimmunology and Multiple Sclerosis, Center for Molecular Neurobiology (ZMNH)University Medical Center Hamburg‐EppendorfHamburgGermany
| | - Markus Morawski
- Molecular Imaging in NeurosciencesPaul Flechsig Institute of Brain ResearchLeipzigGermany
| | - Jürgen Goldschmidt
- Department of Systems Physiology of Learning and MemoryLeibniz Institute for NeurobiologyMagdeburgGermany
| | - Manuel A Friese
- Institute of Neuroimmunology and Multiple Sclerosis, Center for Molecular Neurobiology (ZMNH)University Medical Center Hamburg‐EppendorfHamburgGermany
| | - Steffen Rossner
- Molecular Imaging in NeurosciencesPaul Flechsig Institute of Brain ResearchLeipzigGermany
| | - Gemma Navarro
- Department of Biochemistry and Physiology, Faculty of Pharmacy and Food ScienceUniversity of BarcelonaBarcelonaSpain
- Institut de Neurociències de la Universitat de BarcelonaBarcelonaSpain
| | - Stefan Remy
- Center for Behavioral Brain SciencesOtto von Guericke UniversityMagdeburgGermany
- Department of Cellular NeuroscienceLeibniz Institute for NeurobiologyMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
| | - Carsten Reissner
- Institute of Anatomy and Molecular NeurobiologyWestfälische Wilhelms‐UniversityMünsterGermany
| | - Anna Karpova
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
- Center for Behavioral Brain SciencesOtto von Guericke UniversityMagdeburgGermany
| | - Michael R Kreutz
- RG NeuroplasticityLeibniz Institute for NeurobiologyMagdeburgGermany
- Leibniz Group ‘Dendritic Organelles and Synaptic Function’, Center for Molecular Neurobiology (ZMNH)University Medical Center Hamburg‐EppendorfHamburgGermany
- Center for Behavioral Brain SciencesOtto von Guericke UniversityMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
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53
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Shirotani K, Watanabe K, Hatta D, Kutoku Y, Ohsawa Y, Sunada Y, Kondo T, Inoue H, Iwata N. Alterations of ATG4A and LC3B in neurons derived from Alzheimer's disease patients. Genes Cells 2023; 28:319-325. [PMID: 36719634 DOI: 10.1111/gtc.13010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/24/2023] [Accepted: 01/27/2023] [Indexed: 02/01/2023]
Abstract
We investigated the alterations in autophagy-related molecules in neurons differentiated from induced pluripotent stem cells obtained from patients with Alzheimer's disease (AD). Consistent with our previous microarray data, ATG4A protein was upregulated in the neurons derived from a familial AD patient with an APP-E693Δ mutation who showed accumulation of intracellular amyloid β peptide (Aβ). This upregulation was reversed by inhibiting Aβ production, suggesting that the intracellular Aβ may be responsible for the upregulation of ATG4A. The LC3B-II/LC3B-I ratio, an index of autophagosome formation, was lower in the neurons derived from the AD patient with APP-E693Δ as well as the neurons derived from other familial and sporadic AD patients. These findings indicate that dysregulation of autophagy-related molecules may accelerate the pathogenesis of AD.
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Affiliation(s)
- Keiro Shirotani
- Department of Genome-Based Drug Discovery, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Leading Medical Research Core Unit, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama, Japan
| | - Kaori Watanabe
- Department of Genome-Based Drug Discovery, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Daisuke Hatta
- Department of Genome-Based Drug Discovery, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Yumiko Kutoku
- Department of Neurology, Kawasaki Medical School, Okayama, Japan
| | - Yutaka Ohsawa
- Department of Neurology, Kawasaki Medical School, Okayama, Japan
| | - Yoshihide Sunada
- Department of Neurology, Kawasaki Medical School, Okayama, Japan
| | - Takayuki Kondo
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama, Japan.,Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan
| | - Haruhisa Inoue
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama, Japan.,Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan
| | - Nobuhisa Iwata
- Department of Genome-Based Drug Discovery, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Leading Medical Research Core Unit, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama, Japan
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Biel D, Suárez‐Calvet M, Hager P, Rubinski A, Dewenter A, Steward A, Roemer S, Ewers M, Haass C, Brendel M, Franzmeier N. sTREM2 is associated with amyloid-related p-tau increases and glucose hypermetabolism in Alzheimer's disease. EMBO Mol Med 2023; 15:e16987. [PMID: 36620941 PMCID: PMC9906389 DOI: 10.15252/emmm.202216987] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 01/10/2023] Open
Abstract
Microglial activation occurs early in Alzheimer's disease (AD) and previous studies reported both detrimental and protective effects of microglia on AD progression. Here, we used CSF sTREM2 to investigate disease stage-dependent drivers of microglial activation and to determine downstream consequences on AD progression. We included 402 patients with measures of earliest beta-amyloid (CSF Aβ1-42 ) and late-stage fibrillary Aβ pathology (amyloid-PET centiloid), as well as sTREM2, p-tau181 , and FDG-PET. To determine disease stage, we stratified participants into early Aβ-accumulators (Aβ CSF+/PET-; n = 70) or late Aβ-accumulators (Aβ CSF+/PET+; n = 201) plus 131 controls. In early Aβ-accumulators, higher centiloid was associated with cross-sectional/longitudinal sTREM2 and p-tau181 increases. Further, higher sTREM2 mediated the association between centiloid and cross-sectional/longitudinal p-tau181 increases and higher sTREM2 was associated with FDG-PET hypermetabolism. In late Aβ-accumulators, we found no association between centiloid and sTREM2 but a cross-sectional association between higher sTREM2, higher p-tau181 and glucose hypometabolism. Our findings suggest that a TREM2-related microglial response follows earliest Aβ fibrillization, manifests in inflammatory glucose hypermetabolism and may facilitate subsequent p-tau181 increases in earliest AD.
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Affiliation(s)
- Davina Biel
- Institute for Stroke and Dementia Research (ISD), University HospitalLMU MunichMunichGermany
| | - Marc Suárez‐Calvet
- Barcelonaβeta Brain Research Center (BBRC)Pasqual Maragall FoundationBarcelonaSpain,IMIM (Hospital del Mar Medical Research Institute)BarcelonaSpain,Servei de NeurologiaHospital del MarBarcelonaSpain,Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES)MadridSpain
| | - Paul Hager
- Institute of Radiology and Artificial Intelligence and Informatics in MedicineTU MunichMunichGermany
| | - Anna Rubinski
- Institute for Stroke and Dementia Research (ISD), University HospitalLMU MunichMunichGermany
| | - Anna Dewenter
- Institute for Stroke and Dementia Research (ISD), University HospitalLMU MunichMunichGermany
| | - Anna Steward
- Institute for Stroke and Dementia Research (ISD), University HospitalLMU MunichMunichGermany
| | - Sebastian Roemer
- Institute for Stroke and Dementia Research (ISD), University HospitalLMU MunichMunichGermany,Department of Neurology, University HospitalLMU MunichMunichGermany
| | - Michael Ewers
- Institute for Stroke and Dementia Research (ISD), University HospitalLMU MunichMunichGermany,German Center for Neurodegenerative Diseases (DZNE)MunichGermany
| | - Christian Haass
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany,Munich Cluster for Systems Neurology (SyNergy)MunichGermany,Chair of Metabolic Biochemistry, Biomedical Center (BMC), Faculty of MedicineLMU MunichMunichGermany
| | - Matthias Brendel
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany,Munich Cluster for Systems Neurology (SyNergy)MunichGermany,Department of Nuclear Medicine, University HospitalLMU MunichMunichGermany
| | - Nicolai Franzmeier
- Institute for Stroke and Dementia Research (ISD), University HospitalLMU MunichMunichGermany,Munich Cluster for Systems Neurology (SyNergy)MunichGermany,Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska AcademyUniversity of GothenburgGothenburgGermany
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Riessland M, Orr ME. Translating the Biology of Aging into New Therapeutics for Alzheimer's Disease: Senolytics. J Prev Alzheimers Dis 2023; 10:633-646. [PMID: 37874084 PMCID: PMC11103249 DOI: 10.14283/jpad.2023.104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
The recent FDA-approval for amyloid lowering therapies reflects an unwavering commitment from the Alzheimer's disease (AD) research community to identify treatments for this leading cause of dementia. The clinical benefits achieved by reducing amyloid, though modest, provide evidence that disease modification is possible. Expanding the same tenacity to interventions targeting upstream drivers of AD pathogenesis could significantly impact the disease course. Advanced age is the greatest risk factor for developing AD. Interventions targeting biological aging offer the possibility of disrupting a foundational cause of AD. Senescent cells accumulate with age and contribute to inflammation and age-related diseases like AD. Senolytic drugs that clear senescent cells improve healthy aging, halt AD disease progression in animal models and are undergoing clinical testing. This review explores the biology of aging, the role of senescent cells in AD pathology, and various senotherapeutic approaches such as senolytics, dampening the SASP (senescence associated secretory phenotype), senescence pathway inhibition, vaccines, and prodrugs. We highlight ongoing clinical trials evaluating the safety and efficacy of the most advanced senolytic approach, dasatinib and quercetin (D+Q), including an ongoing Phase II senolytic trial supported by the Alzheimer's Drug Discovery Foundation (ADDF). Challenges in the field of senotherapy for AD, including target engagement and biomarker development, are addressed. Ultimately, this research pursuit may lead to an effective treatment for AD and provide the field with another disease-modifying therapy to be used, alone or in combination, with other emerging treatment options.
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Affiliation(s)
- M Riessland
- Miranda E. Orr, 575 Patterson Ave, Winston-Salem, NC 27101, Telephone Number: (336)716-7804,
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56
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Guo J, Huang X, Dou L, Yan M, Shen T, Tang W, Li J. Aging and aging-related diseases: from molecular mechanisms to interventions and treatments. Signal Transduct Target Ther 2022; 7:391. [PMID: 36522308 PMCID: PMC9755275 DOI: 10.1038/s41392-022-01251-0] [Citation(s) in RCA: 299] [Impact Index Per Article: 149.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 11/03/2022] [Accepted: 11/10/2022] [Indexed: 12/23/2022] Open
Abstract
Aging is a gradual and irreversible pathophysiological process. It presents with declines in tissue and cell functions and significant increases in the risks of various aging-related diseases, including neurodegenerative diseases, cardiovascular diseases, metabolic diseases, musculoskeletal diseases, and immune system diseases. Although the development of modern medicine has promoted human health and greatly extended life expectancy, with the aging of society, a variety of chronic diseases have gradually become the most important causes of disability and death in elderly individuals. Current research on aging focuses on elucidating how various endogenous and exogenous stresses (such as genomic instability, telomere dysfunction, epigenetic alterations, loss of proteostasis, compromise of autophagy, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, altered intercellular communication, deregulated nutrient sensing) participate in the regulation of aging. Furthermore, thorough research on the pathogenesis of aging to identify interventions that promote health and longevity (such as caloric restriction, microbiota transplantation, and nutritional intervention) and clinical treatment methods for aging-related diseases (depletion of senescent cells, stem cell therapy, antioxidative and anti-inflammatory treatments, and hormone replacement therapy) could decrease the incidence and development of aging-related diseases and in turn promote healthy aging and longevity.
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Affiliation(s)
- Jun Guo
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, China
| | - Xiuqing Huang
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, China
| | - Lin Dou
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, China
| | - Mingjing Yan
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, China
| | - Tao Shen
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, China.
| | - Weiqing Tang
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, China.
| | - Jian Li
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, China.
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57
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Reflecting on 2022. PLoS Biol 2022; 20:e3001957. [PMID: 36525462 PMCID: PMC9803267 DOI: 10.1371/journal.pbio.3001957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 12/30/2022] [Indexed: 12/23/2022] Open
Abstract
As 2022 draws to a close, we look back at some of the recent changes that have taken place at PLOS Biology, highlight some of our editors' favorite moments from the past year across the life sciences, and thank our editors, authors and peer-reviewers.
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58
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Rosenberry TL, Zhou HX, Stagg SM, Paravastu AK. Oligomer Formation by Amyloid-β42 in a Membrane-Mimicking Environment in Alzheimer's Disease. Molecules 2022; 27:8804. [PMID: 36557940 PMCID: PMC9781152 DOI: 10.3390/molecules27248804] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/17/2022] [Accepted: 11/23/2022] [Indexed: 12/15/2022] Open
Abstract
The brains of Alzheimer's disease (AD) patients contain numerous amyloid plaques that are diagnostic of the disease. The plaques are primarily composed of the amyloidogenic peptides proteins Aβ40 and Aβ42, which are derived by the processing of the amyloid pre-cursor protein (APP) by two proteases called β-secretase and γ-secretase. Aβ42 differs from Aβ40 in having two additional hydrophobic amino acids, ILE and ALA, at the C-terminus. A small percentage of AD is autosomal dominant (ADAD) and linked either to the genes for the presenilins, which are part of γ-secretase, or APP. Because ADAD shares most pathogenic features with widespread late-onset AD, Aβ peptides have become the focus of AD research. Fibrils formed by the aggregation of these peptides are the major component of plaques and were initially targeted in AD therapy. However, the fact that the abundance of plaques does not correlate well with cognitive decline in AD patients has led investigators to examine smaller Aβ aggregates called oligomers. The low levels and heterogeneity of Aβ oligomers have made the determination of their structures difficult, but recent structure determinations of oligomers either formed or initiated in detergents have been achieved. We report here on the structures of these oligomers and suggest how they may be involved in AD.
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Affiliation(s)
- Terrone L. Rosenberry
- The Departments of Neuroscience and Pharmacology, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Huan-Xiang Zhou
- Departments of Chemistry and Physics, University of Illinois Chicago, Chicago, IL 60608, USA
| | - Scott M. Stagg
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA
- Department of Biological Sciences, Florida State University, Tallahassee, FL 32306, USA
| | - Anant K. Paravastu
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive NW, Atlanta, GA 30332, USA
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Bezprozvanny I. Alzheimer's disease - Where do we go from here? Biochem Biophys Res Commun 2022; 633:72-76. [PMID: 36344168 DOI: 10.1016/j.bbrc.2022.08.075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 08/23/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Ilya Bezprozvanny
- Department of Physiology, UT Southwestern Medical Center at Dallas, Dallas, TX, 75390, USA; Laboratory of Molecular Neurodegeneration, Peter the Great St Petersburg State Polytechnical University, St. Petersburg, 195251, Russia.
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Lim J, Kim S, Lee C, Park J, Yang G, Yook T. Verbenalin Reduces Amyloid-Beta Peptide Generation in Cellular and Animal Models of Alzheimer's Disease. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27248678. [PMID: 36557811 PMCID: PMC9781082 DOI: 10.3390/molecules27248678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/27/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022]
Abstract
Verbenalin, among the major constituents of Verbena officinalis, has been reported to exhibit sleep-promoting and antioxidant activities. This study demonstrates the effects of verbenalin on amyloid-beta (Aβ) peptide generation in Swedish mutant amyloid precursor protein (APP)-overexpressing Neuro2a cells (SweAPP/N2a) and in Alzheimer's disease (AD) animal models. We further performed molecular biological analyses of these in vitro and in vivo models of AD. The effects of verbenalin were assessed based on the expression of factors related to Aβ peptide production using Western blotting, enzyme-linked immunosorbent assay, and immunohistochemistry (IHC). The intracellular expression and release of APP protein were both decreased by verbenalin treatment in SweAPP/N2a cells. Thus, the production of Aβ peptides was decreased. Compared to those in AD transgenic (Tg) mice, IHC revealed that verbenalin-treated animals showed decreased Aβ and tau expression levels in the hippocampus. In addition, verbenalin restored the expression of brain-derived neurotrophic factor (BDNF) in the hippocampus of AD animal models. These findings suggest that verbenalin may decrease Aβ formation both in vitro and in vivo. Verbenalin may also help improve the pathological hallmarks of AD.
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Affiliation(s)
- Juhee Lim
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Woosuk University, Wanju 55338, Republic of Korea
| | - Seokhee Kim
- College of Korean Medicine, Woosuk University, Jeonju 54986, Republic of Korea
| | - Changhyun Lee
- College of Korean Medicine, Woosuk University, Jeonju 54986, Republic of Korea
| | - Jeongwoo Park
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Gabsik Yang
- College of Korean Medicine, Woosuk University, Jeonju 54986, Republic of Korea
- Correspondence: (G.Y.); (T.Y.); Tel.: +82-63-220-8625 (T.Y.); Fax: +82-63-220-8400 (T.Y.)
| | - Taehan Yook
- College of Korean Medicine, Woosuk University, Jeonju 54986, Republic of Korea
- Correspondence: (G.Y.); (T.Y.); Tel.: +82-63-220-8625 (T.Y.); Fax: +82-63-220-8400 (T.Y.)
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Wang B, Liu W, Sun F. Nucleosome assembly protein 1-like 5 alleviates Alzheimer's disease-like pathological characteristics in a cell model. Front Mol Neurosci 2022; 15:1034766. [PMID: 36568274 PMCID: PMC9773259 DOI: 10.3389/fnmol.2022.1034766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 11/24/2022] [Indexed: 12/14/2022] Open
Abstract
Alzheimer's disease (AD) remains one of the most common dementias of neurodegenerative disease-related diseases. Nucleosome assembly protein 1-like 5 (NAP1L5) belongs to the NAP1L protein family, which acts as a histone chaperone. However, the function and mechanism of NAP1L5 in AD are still unclear. Bioinformatics analysis, RT-qPCR, and Western blotting results showed that NAP1L5 was downregulated in the brain tissues of AD patients and a mouse cell model of AD. NAP1L5 overexpression alleviated (Amyloid-β precursor protein) APP metabolism and Tau phosphorylation. We further demonstrated that NAP1L5 regulated the AD-like pathological characteristics through the GSK3B/Wnt/β-Catenin signaling pathway. Moreover, we showed that the Wnt/β-Catenin signaling pathway, regulated by NAP1L5, was mediated by AQP1-mediated mechanism in N2a-APP695sw cell. In sum, these results suggested that NAP1L5 overexpression has neuroprotective effects and might act as potential biomarker and target for the diagnosis and treatment of AD.
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Affiliation(s)
- Bingyan Wang
- Department of Anesthesiology, The Second Hospital of Tianjin Medical University, Tianjin, China
| | - Weiying Liu
- Department of Pathogen Biology, School of Basic Medicine, Tianjin Medical University, Tianjin, China,*Correspondence: Weiying Liu,
| | - Fengxian Sun
- Department of Physiology and Pathophysiology, School of Basic Medicine, Tianjin Medical University, Tianjin, China,Fengxian Sun,
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Hao Y, Xie B, Fu X, Xu R, Yang Y. New Insights into lncRNAs in Aβ Cascade Hypothesis of Alzheimer's Disease. Biomolecules 2022; 12:biom12121802. [PMID: 36551230 PMCID: PMC9775548 DOI: 10.3390/biom12121802] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/24/2022] [Accepted: 11/29/2022] [Indexed: 12/04/2022] Open
Abstract
Alzheimer's disease (AD) is the most common type of dementia, but its pathogenesis is not fully understood, and effective drugs to treat or reverse the progression of the disease are lacking. Long noncoding RNAs (lncRNAs) are abnormally expressed and deregulated in AD and are closely related to the occurrence and development of AD. In addition, the high tissue specificity and spatiotemporal specificity make lncRNAs particularly attractive as diagnostic biomarkers and specific therapeutic targets. Therefore, an in-depth understanding of the regulatory mechanisms of lncRNAs in AD is essential for developing new treatment strategies. In this review, we discuss the unique regulatory functions of lncRNAs in AD, ranging from Aβ production to clearance, with a focus on their interaction with critical molecules. Additionally, we highlight the advantages and challenges of using lncRNAs as biomarkers for diagnosis or therapeutic targets in AD and present future perspectives in clinical practice.
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Affiliation(s)
- Yitong Hao
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun 130021, China
| | - Bo Xie
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun 130021, China
| | - Xiaoshu Fu
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun 130021, China
| | - Rong Xu
- Department of Hepatobiliary and Pancreatic Surgery, The First Hospital of Jilin University, Changchun 130021, China
| | - Yu Yang
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun 130021, China
- Correspondence:
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Kopp KO, Glotfelty EJ, Li Y, Greig NH. Glucagon-like peptide-1 (GLP-1) receptor agonists and neuroinflammation: Implications for neurodegenerative disease treatment. Pharmacol Res 2022; 186:106550. [PMID: 36372278 PMCID: PMC9712272 DOI: 10.1016/j.phrs.2022.106550] [Citation(s) in RCA: 55] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/03/2022] [Accepted: 11/06/2022] [Indexed: 11/13/2022]
Abstract
Chronic, excessive neuroinflammation is a key feature of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). However, neuroinflammatory pathways have yet to be effectively targeted in clinical treatments for such diseases. Interestingly, increased inflammation and neurodegenerative disease risk have been associated with type 2 diabetes mellitus (T2DM) and insulin resistance (IR), suggesting that treatments that mitigate T2DM pathology may be successful in treating neuroinflammatory and neurodegenerative pathology as well. Glucagon-like peptide-1 (GLP-1) is an incretin hormone that promotes healthy insulin signaling, regulates blood sugar levels, and suppresses appetite. Consequently, numerous GLP-1 receptor (GLP-1R) stimulating drugs have been developed and approved by the US Food and Drug Administration (FDA) and related global regulatory authorities for the treatment of T2DM. Furthermore, GLP-1R stimulating drugs have been associated with anti-inflammatory, neurotrophic, and neuroprotective properties in neurodegenerative disorder preclinical models, and hence hold promise for repurposing as a treatment for neurodegenerative diseases. In this review, we discuss incretin signaling, neuroinflammatory pathways, and the intersections between neuroinflammation, brain IR, and neurodegenerative diseases, with a focus on AD and PD. We additionally overview current FDA-approved incretin receptor stimulating drugs and agents in development, including unimolecular single, dual, and triple receptor agonists, and highlight those in clinical trials for neurodegenerative disease treatment. We propose that repurposing already-approved GLP-1R agonists for the treatment of neurodegenerative diseases may be a safe, efficacious, and cost-effective strategy for ameliorating AD and PD pathology by quelling neuroinflammation.
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Affiliation(s)
- Katherine O Kopp
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program National Institute on Aging, NIH, Baltimore, MD 21224, United States.
| | - Elliot J Glotfelty
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program National Institute on Aging, NIH, Baltimore, MD 21224, United States; Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Yazhou Li
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program National Institute on Aging, NIH, Baltimore, MD 21224, United States
| | - Nigel H Greig
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program National Institute on Aging, NIH, Baltimore, MD 21224, United States.
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La Barbera L, Nobili A, Cauzzi E, Paoletti I, Federici M, Saba L, Giacomet C, Marino R, Krashia P, Melone M, Keller F, Mercuri NB, Viscomi MT, Conti F, D’Amelio M. Upregulation of Ca 2+-binding proteins contributes to VTA dopamine neuron survival in the early phases of Alzheimer's disease in Tg2576 mice. Mol Neurodegener 2022; 17:76. [PMID: 36434727 PMCID: PMC9700939 DOI: 10.1186/s13024-022-00580-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 10/31/2022] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Recent clinical and experimental studies have highlighted the involvement of Ventral Tegmental Area (VTA) dopamine (DA) neurons for the early pathogenesis of Alzheimer's Disease (AD). We have previously described a progressive and selective degeneration of these neurons in the Tg2576 mouse model of AD, long before amyloid-beta plaque formation. The degenerative process in DA neurons is associated with an autophagy flux impairment, whose rescue can prevent neuronal loss. Impairments in autophagy can be the basis for accumulation of damaged mitochondria, leading to disturbance in calcium (Ca2+) homeostasis, and to functional and structural deterioration of DA neurons. METHODS In Tg2576 mice, we performed amperometric recordings of DA levels and analysis of dopaminergic fibers in the Nucleus Accumbens - a major component of the ventral striatum precociously affected in AD patients - together with retrograde tracing, to identify the most vulnerable DA neuron subpopulations in the VTA. Then, we focused on these neurons to analyze mitochondrial integrity and Apoptosis-inducing factor (AIF) localization by electron and confocal microscopy, respectively. Stereological cell count was also used to evaluate degeneration of DA neuron subpopulations containing the Ca2+-binding proteins Calbindin-D28K and Calretinin. The expression levels for these proteins were analyzed by western blot and confocal microscopy. Lastly, using electrophysiology and microfluorometry we analyzed VTA DA neuron intrinsic properties and cytosolic free Ca2+ levels. RESULTS We found a progressive degeneration of mesolimbic DA neurons projecting to the ventral striatum, located in the paranigral nucleus and parabrachial pigmented subnucleus of the VTA. At the onset of degeneration (3 months of age), the vulnerable DA neurons in the Tg2576 accumulate damaged mitochondria, while AIF translocates from the mitochondria to the nucleus. Although we describe an age-dependent loss of the DA neurons expressing Calbindin-D28K or Calretinin, we observed that the remaining cells upregulate the levels of Ca2+-binding proteins, and the free cytosolic levels of Ca2+ in these neurons are significantly decreased. Coherently, TUNEL-stained Tg2576 DA neurons express lower levels of Calbindin-D28K when compared with non-apoptotic cells. CONCLUSION Overall, our results suggest that the overexpression of Ca2+-binding proteins in VTA DA neurons might be an attempt of cells to survive by increasing their ability to buffer free Ca2+. Exploring strategies to overexpress Ca2+-binding proteins could be fundamental to reduce neuronal suffering and improve cognitive and non-cognitive functions in AD.
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Affiliation(s)
- Livia La Barbera
- grid.9657.d0000 0004 1757 5329Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 00128 Rome, Italy ,grid.417778.a0000 0001 0692 3437Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143 Rome, Italy
| | - Annalisa Nobili
- grid.9657.d0000 0004 1757 5329Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 00128 Rome, Italy ,grid.417778.a0000 0001 0692 3437Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143 Rome, Italy
| | - Emma Cauzzi
- grid.417778.a0000 0001 0692 3437Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143 Rome, Italy ,grid.6530.00000 0001 2300 0941Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Ilaria Paoletti
- grid.9657.d0000 0004 1757 5329Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 00128 Rome, Italy
| | - Mauro Federici
- grid.417778.a0000 0001 0692 3437Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143 Rome, Italy
| | - Luana Saba
- grid.9657.d0000 0004 1757 5329Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 00128 Rome, Italy ,grid.417778.a0000 0001 0692 3437Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143 Rome, Italy
| | - Cecilia Giacomet
- grid.6530.00000 0001 2300 0941Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Ramona Marino
- grid.9657.d0000 0004 1757 5329Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 00128 Rome, Italy
| | - Paraskevi Krashia
- grid.417778.a0000 0001 0692 3437Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143 Rome, Italy ,grid.9657.d0000 0004 1757 5329Department of Sciences and Technologies for Humans and Environment, Università Campus Bio-Medico di Roma, 00128 Rome, Italy
| | - Marcello Melone
- grid.7010.60000 0001 1017 3210Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche (UNIVPM), 60020 Ancona, Italy ,Center for Neurobiology of Aging, IRCCS Istituto Nazionale Ricovero e Cura Anziani (INRCA), 60020 Ancona, Italy
| | - Flavio Keller
- grid.9657.d0000 0004 1757 5329Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 00128 Rome, Italy
| | - Nicola Biagio Mercuri
- grid.417778.a0000 0001 0692 3437Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143 Rome, Italy ,grid.6530.00000 0001 2300 0941Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Maria Teresa Viscomi
- grid.8142.f0000 0001 0941 3192Department of Life Science and Public Health; Section of Histology and Embryology, Università Cattolica del Sacro Cuore, 00168 Rome, Italy ,grid.414603.4Fondazione Policlinico Universitario “A. Gemelli”, IRCCS, 00168 Rome, Italy
| | - Fiorenzo Conti
- grid.7010.60000 0001 1017 3210Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche (UNIVPM), 60020 Ancona, Italy ,Center for Neurobiology of Aging, IRCCS Istituto Nazionale Ricovero e Cura Anziani (INRCA), 60020 Ancona, Italy ,grid.7010.60000 0001 1017 3210Foundation for Molecular Medicine, Università Politecnica delle Marche, 60020 Ancona, Italy
| | - Marcello D’Amelio
- grid.9657.d0000 0004 1757 5329Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, 00128 Rome, Italy ,grid.417778.a0000 0001 0692 3437Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143 Rome, Italy
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Busch L, Eggert S, Endres K, Bufe B. The Hidden Role of Non-Canonical Amyloid β Isoforms in Alzheimer's Disease. Cells 2022; 11:3421. [PMID: 36359817 PMCID: PMC9654995 DOI: 10.3390/cells11213421] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/18/2022] [Accepted: 10/20/2022] [Indexed: 09/08/2024] Open
Abstract
Recent advances have placed the pro-inflammatory activity of amyloid β (Aβ) on microglia cells as the focus of research on Alzheimer's Disease (AD). Researchers are confronted with an astonishing spectrum of over 100 different Aβ variants with variable length and chemical modifications. With the exception of Aβ1-42 and Aβ1-40, the biological significance of most peptides for AD is as yet insufficiently understood. We therefore aim to provide a comprehensive overview of the contributions of these neglected Aβ variants to microglia activation. First, the impact of Aβ receptors, signaling cascades, scavenger mechanisms, and genetic variations on the physiological responses towards various Aβ species is described. Furthermore, we discuss the importance of different types of amyloid precursor protein processing for the generation of these Aβ variants in microglia, astrocytes, oligodendrocytes, and neurons, and highlight how alterations in secondary structures and oligomerization affect Aβ neurotoxicity. In sum, the data indicate that gene polymorphisms in Aβ-driven signaling pathways in combination with the production and activity of different Aβ variants might be crucial factors for the initiation and progression of different forms of AD. A deeper assessment of their interplay with glial cells may pave the way towards novel therapeutic strategies for individualized medicine.
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Affiliation(s)
- Lukas Busch
- Department of Informatics and Microsystems Technology, University of Applied Sciences Kaiserslautern, D-66482 Zweibruecken, Germany
| | - Simone Eggert
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, D-37075 Goettingen, Germany
| | - Kristina Endres
- Department of Psychiatry and Psychotherapy, University Medical Centre of the Johannes Gutenberg University, D-55131 Mainz, Germany
| | - Bernd Bufe
- Department of Informatics and Microsystems Technology, University of Applied Sciences Kaiserslautern, D-66482 Zweibruecken, Germany
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Erdinger S, Amrein I, Back M, Ludewig S, Korte M, von Engelhardt J, Wolfer DP, Müller UC. Lack of APLP1 leads to subtle alterations in neuronal morphology but does not affect learning and memory. Front Mol Neurosci 2022; 15:1028836. [DOI: 10.3389/fnmol.2022.1028836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 10/11/2022] [Indexed: 11/13/2022] Open
Abstract
The amyloid precursor protein APP plays a crucial role in Alzheimer pathogenesis. Its physiological functions, however, are only beginning to be unraveled. APP belongs to a small gene family, including besides APP the closely related amyloid precursor-like proteins APLP1 and APLP2, that all constitute synaptic adhesion proteins. While APP and APLP2 are ubiquitously expressed, APLP1 is specific for the nervous system. Previous genetic studies, including combined knockouts of several family members, pointed towards a unique role for APLP1, as only APP/APLP1 double knockouts were viable. We now examined brain and neuronal morphology in APLP1 single knockout (KO) animals, that have to date not been studied in detail. Here, we report that APLP1-KO mice show normal spine density in hippocampal CA1 pyramidal cells and subtle alterations in dendritic complexity. Extracellular field recordings revealed normal basal synaptic transmission and no alterations in synaptic plasticity (LTP). Further, behavioral studies revealed in APLP1-KO mice a small deficit in motor function and reduced diurnal locomotor activity, while learning and memory were not affected by the loss of APLP1. In summary, our study indicates that APP family members serve both distinct and overlapping functions that need to be considered for therapeutic treatments of Alzheimer’s disease.
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The Asparaginyl Endopeptidase Legumain: An Emerging Therapeutic Target and Potential Biomarker for Alzheimer’s Disease. Int J Mol Sci 2022; 23:ijms231810223. [PMID: 36142134 PMCID: PMC9499314 DOI: 10.3390/ijms231810223] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 08/30/2022] [Accepted: 09/02/2022] [Indexed: 11/21/2022] Open
Abstract
Alzheimer’s disease (AD) is incurable dementia closely associated with aging. Most cases of AD are sporadic, and very few are inherited; the pathogenesis of sporadic AD is complex and remains to be elucidated. The asparaginyl endopeptidase (AEP) or legumain is the only recognized cysteine protease that specifically hydrolyzes peptide bonds after asparagine residues in mammals. The expression level of AEPs in healthy brains is far lower than that of peripheral organs. Recently, growing evidence has indicated that aging may upregulate and overactivate brain AEPs. The overactivation of AEPs drives the onset of AD through cleaving tau and amyloid precursor proteins (APP), and SET, an inhibitor of protein phosphatase 2A (PP2A). The AEP-mediated cleavage of these peptides enhances amyloidosis, promotes tau hyperphosphorylation, and ultimately induces neurodegeneration and cognitive impairment. Upregulated AEPs and related deleterious reactions constitute upstream events of amyloid/tau toxicity in the brain, and represent early pathological changes in AD. Thus, upregulated AEPs are an emerging drug target for disease modification and a potential biomarker for predicting preclinical AD. However, the presence of the blood–brain barrier greatly hinders establishing body-fluid-based methods to measure brain AEPs. Research on AEP-activity-based imaging probes and our recent work suggest that the live brain imaging of AEPs could be used to evaluate its predictive efficacy as an AD biomarker. To advance translational research in this area, AEP imaging probes applicable to human brain and AEP inhibitors with good druggability are urgently needed.
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