1
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Ricci FS, Stanga S, Mezzanotte M, Marinaccio C, D'Alessandro R, Somà A, Sottemano S, Conio A, Morana G, Spada M, Boido M, Mongini TE. Biochemical characterization on muscle tissue of a novel biallelic ACO2 mutation in an infant with progressive encephalopathy. JIMD Rep 2024; 65:3-9. [PMID: 38186851 PMCID: PMC10764196 DOI: 10.1002/jmd2.12400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 10/06/2023] [Accepted: 10/10/2023] [Indexed: 01/09/2024] Open
Abstract
The ACO2 gene encodes the mitochondrial protein aconitate hydratase, which is responsible for catalyzing the interconversion of citrate into isocitrate in the tricarboxylic acid (TCA) cycle. Mitochondrial aconitase is expressed ubiquitously, and deficiencies in TCA-cycle enzymes have been reported to cause various neurodegenerative diseases due to disruption of cellular energy metabolism and development of oxidative stress. We investigated a severe early infantile-onset neurometabolic syndrome due to a homozygous novel variant in exon 13 of the ACO2 gene. The in vitro pathogenicity of this variant of unknown significance was demonstrated by the loss of both protein expression and its enzymatic activity on muscle tissue sample taken from the patient. The patient presented with progressive encephalopathy soon after birth, characterized by hypotonia, progressive severe muscle atrophy, and respiratory failure. Serial brain magnetic resonance imaging showed progressive abnormalities compatible with a metabolic disorder, possibly mitochondrial. Muscle biopsy disclosed moderate myopathic alterations and features consistent with a mitochondriopathy albeit nonspecific. The course was characterized by progressive worsening of the clinical and neurological picture, and the patient died at 5 months of age. This study provides the first report on the validation in muscle from human subjects regarding in vitro analysis for mitochondrial aconitase activity. To our knowledge, no prior reports have demonstrated a correlation of phenotypic and diagnostic characteristics with in vitro muscle enzymatic activity of mitochondrial aconitase in humans. In conclusion, this case further expands the genetic spectrum of ACO2 variants and defines a complex case of severe neonatal neurometabolic disorder.
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Affiliation(s)
- Federica Silvia Ricci
- Division of Child and Adolescent Neuropsychiatry, Department of Public Health and Pediatric SciencesUniversity of TurinTurinItaly
| | - Serena Stanga
- Department of Neuroscience “Rita Levi Montalcini”Neuroscience Institute Cavalieri Ottolenghi, University of TurinTurinItaly
| | - Mariarosa Mezzanotte
- Department of Neuroscience “Rita Levi Montalcini”Neuroscience Institute Cavalieri Ottolenghi, University of TurinTurinItaly
| | - Cristina Marinaccio
- Division of Child and Adolescent Neuropsychiatry, Department of Child Care and PathologyChildren Hospital “Regina Margherita”TurinItaly
| | - Rossella D'Alessandro
- Division of Child and Adolescent Neuropsychiatry, Department of Child Care and PathologyChildren Hospital “Regina Margherita”TurinItaly
| | - Alessandra Somà
- Division of Child and Adolescent Neuropsychiatry, Department of Public Health and Pediatric SciencesUniversity of TurinTurinItaly
| | - Stefano Sottemano
- Division of Child and Adolescent Neuropsychiatry, Department of Public Health and Pediatric SciencesUniversity of TurinTurinItaly
| | - Alessandra Conio
- Pediatric Intensive Care Unit, Anesthesia, Resuscitation and Emergency DepartmentUniversity of TurinTurinItaly
| | - Giovanni Morana
- Neuroradiology Unit, Department of Neuroscience “Rita Levi Montalcini”University of TurinTurinItaly
| | - Marco Spada
- Division of Child and Adolescent Neuropsychiatry, Department of Child Care and PathologyChildren Hospital “Regina Margherita”TurinItaly
| | - Marina Boido
- Department of Neuroscience “Rita Levi Montalcini”Neuroscience Institute Cavalieri Ottolenghi, University of TurinTurinItaly
| | - Tiziana E. Mongini
- Division of Neurology 1, Department of Neuroscience “Rita Levi Montalcini”University of TurinTurinItaly
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2
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Selçuk B, Aksu T, Dereli O, Adebali O. Downregulated NPAS4 in multiple brain regions is associated with major depressive disorder. Sci Rep 2023; 13:21596. [PMID: 38062059 PMCID: PMC10703936 DOI: 10.1038/s41598-023-48646-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 11/29/2023] [Indexed: 12/18/2023] Open
Abstract
Major Depressive Disorder (MDD) is a commonly observed psychiatric disorder that affects more than 2% of the world population with a rising trend. However, disease-associated pathways and biomarkers are yet to be fully comprehended. In this study, we analyzed previously generated RNA-seq data across seven different brain regions from three distinct studies to identify differentially and co-expressed genes for patients with MDD. Differential gene expression (DGE) analysis revealed that NPAS4 is the only gene downregulated in three different brain regions. Furthermore, co-expressing gene modules responsible for glutamatergic signaling are negatively enriched in these regions. We used the results of both DGE and co-expression analyses to construct a novel MDD-associated pathway. In our model, we propose that disruption in glutamatergic signaling-related pathways might be associated with the downregulation of NPAS4 and many other immediate-early genes (IEGs) that control synaptic plasticity. In addition to DGE analysis, we identified the relative importance of KEGG pathways in discriminating MDD phenotype using a machine learning-based approach. We anticipate that our study will open doors to developing better therapeutic approaches targeting glutamatergic receptors in the treatment of MDD.
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Affiliation(s)
- Berkay Selçuk
- Molecular Biology, Genetics and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, 34956, Istanbul, Turkey
| | - Tuana Aksu
- Molecular Biology, Genetics and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, 34956, Istanbul, Turkey
| | - Onur Dereli
- Molecular Biology, Genetics and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, 34956, Istanbul, Turkey
| | - Ogün Adebali
- Molecular Biology, Genetics and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, 34956, Istanbul, Turkey.
- TÜBİTAK Research Institute for Fundamental Sciences, 41470, Gebze, Turkey.
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3
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Al-Kuraishy HM, Jabir MS, Al-Gareeb AI, Albuhadily AK, Albukhaty S, Sulaiman GM, Batiha GES. Evaluation and targeting of amyloid precursor protein (APP)/amyloid beta (Aβ) axis in amyloidogenic and non-amyloidogenic pathways: A time outside the tunnel. Ageing Res Rev 2023; 92:102119. [PMID: 37931848 DOI: 10.1016/j.arr.2023.102119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 11/02/2023] [Accepted: 11/03/2023] [Indexed: 11/08/2023]
Abstract
In Alzheimer disease (AD), amyloid precursor protein (APP) and production of amyloid beta (Aβ) which is generated by amyloidogenic pathway is implicated in neurotoxicity and neuronal cell deaths. However, physiological Aβ level is essential to improves neuronal survival, attenuates neuronal apoptosis and has neuroprotective effect. In addition, physiological APP level has neurotrophic effect on the central nervous system (CNS). APP has a critical role in the brain growth and development via activation of long-term potentiation (LTP) and acceleration of neurite outgrowth. Moreover, APP is cleaved by α secretase to form a neuroprotective soluble APP alpha (sAPPα) in non-amyloidogenic pathway. Consequently, this mini-review purposes to highlight the possible beneficial role of APP and Aβ. In addition, this mini-review discussed the modulation of APP processing and Aβ production.
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Affiliation(s)
- Hayder M Al-Kuraishy
- Department of Clinical pharmacology and Medicine, College of Medicine, Mustansiriyah University, Baghdad, Iraq
| | - Majid S Jabir
- Department of Applied science, University of Technology, Iraq.
| | - Ali I Al-Gareeb
- Department of Clinical pharmacology and Medicine, College of Medicine, Mustansiriyah University, Baghdad, Iraq
| | - Ali K Albuhadily
- Department of Clinical pharmacology and Medicine, College of Medicine, Mustansiriyah University, Baghdad, Iraq
| | - Salim Albukhaty
- Department of Chemistry, College of Science, University of Misan, Maysan 62001, Iraq
| | | | - Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour, AlBeheira 22511, Egypt
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4
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Lobos P, Vega-Vásquez I, Bruna B, Gleitze S, Toledo J, Härtel S, Hidalgo C, Paula-Lima A. Amyloid β-Oligomers Inhibit the Nuclear Ca 2+ Signals and the Neuroprotective Gene Expression Induced by Gabazine in Hippocampal Neurons. Antioxidants (Basel) 2023; 12:1972. [PMID: 38001825 PMCID: PMC10669355 DOI: 10.3390/antiox12111972] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 10/31/2023] [Accepted: 11/04/2023] [Indexed: 11/26/2023] Open
Abstract
Hippocampal neuronal activity generates dendritic and somatic Ca2+ signals, which, depending on stimulus intensity, rapidly propagate to the nucleus and induce the expression of transcription factors and genes with crucial roles in cognitive functions. Soluble amyloid-beta oligomers (AβOs), the main synaptotoxins engaged in the pathogenesis of Alzheimer's disease, generate aberrant Ca2+ signals in primary hippocampal neurons, increase their oxidative tone and disrupt structural plasticity. Here, we explored the effects of sub-lethal AβOs concentrations on activity-generated nuclear Ca2+ signals and on the Ca2+-dependent expression of neuroprotective genes. To induce neuronal activity, neuron-enriched primary hippocampal cultures were treated with the GABAA receptor blocker gabazine (GBZ), and nuclear Ca2+ signals were measured in AβOs-treated or control neurons transfected with a genetically encoded nuclear Ca2+ sensor. Incubation (6 h) with AβOs significantly reduced the nuclear Ca2+ signals and the enhanced phosphorylation of cyclic AMP response element-binding protein (CREB) induced by GBZ. Likewise, incubation (6 h) with AβOs significantly reduced the GBZ-induced increases in the mRNA levels of neuronal Per-Arnt-Sim domain protein 4 (Npas4), brain-derived neurotrophic factor (BDNF), ryanodine receptor type-2 (RyR2), and the antioxidant enzyme NADPH-quinone oxidoreductase (Nqo1). Based on these findings we propose that AβOs, by inhibiting the generation of activity-induced nuclear Ca2+ signals, disrupt key neuroprotective gene expression pathways required for hippocampal-dependent learning and memory processes.
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Affiliation(s)
- Pedro Lobos
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile; (P.L.); (I.V.-V.); (S.G.); (S.H.)
- Advanced Clinical Research Center, Clinical Hospital, Universidad de Chile, Santiago 8380456, Chile; (B.B.); (J.T.)
| | - Ignacio Vega-Vásquez
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile; (P.L.); (I.V.-V.); (S.G.); (S.H.)
- Advanced Scientific Equipment Network (REDECA), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile
| | - Barbara Bruna
- Advanced Clinical Research Center, Clinical Hospital, Universidad de Chile, Santiago 8380456, Chile; (B.B.); (J.T.)
| | - Silvia Gleitze
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile; (P.L.); (I.V.-V.); (S.G.); (S.H.)
| | - Jorge Toledo
- Advanced Clinical Research Center, Clinical Hospital, Universidad de Chile, Santiago 8380456, Chile; (B.B.); (J.T.)
- Advanced Scientific Equipment Network (REDECA), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile
| | - Steffen Härtel
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile; (P.L.); (I.V.-V.); (S.G.); (S.H.)
- Laboratory for Scientific Image Analysis, Center for Medical Informatics and Telemedicine, Faculty of Medicine, Universidad de Chile, Santiago 8380000, Chile
- Anatomy and Biology of Development Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago 8380000, Chile
| | - Cecilia Hidalgo
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile; (P.L.); (I.V.-V.); (S.G.); (S.H.)
- Department of Neuroscience, Faculty of Medicine, Universidad de Chile, Santiago 8380000, Chile
- Physiology and Biophysics Program, Institute of Biomedical Sciences and Center for Exercise, Metabolism and Cancer Studies, Faculty of Medicine, Universidad de Chile, Santiago 8380000, Chile
| | - Andrea Paula-Lima
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile; (P.L.); (I.V.-V.); (S.G.); (S.H.)
- Department of Neuroscience, Faculty of Medicine, Universidad de Chile, Santiago 8380000, Chile
- Interuniversity Center for Healthy Aging (CIES), Santiago 8380000, Chile
- Institute for Research in Dental Sciences (ICOD), Faculty of Dentistry, Universidad de Chile, Santiago 8380544, Chile
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5
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Suelves N, Saleki S, Ibrahim T, Palomares D, Moonen S, Koper MJ, Vrancx C, Vadukul DM, Papadopoulos N, Viceconte N, Claude E, Vandenberghe R, von Arnim CAF, Constantinescu SN, Thal DR, Decottignies A, Kienlen-Campard P. Senescence-related impairment of autophagy induces toxic intraneuronal amyloid-β accumulation in a mouse model of amyloid pathology. Acta Neuropathol Commun 2023; 11:82. [PMID: 37198698 DOI: 10.1186/s40478-023-01578-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 05/07/2023] [Indexed: 05/19/2023] Open
Abstract
Aging is the main risk factor for Alzheimer's disease (AD) and other neurodegenerative pathologies, but the molecular and cellular changes underlying pathological aging of the nervous system are poorly understood. AD pathology seems to correlate with the appearance of cells that become senescent due to the progressive accumulation of cellular insults causing DNA damage. Senescence has also been shown to reduce the autophagic flux, a mechanism involved in clearing damaged proteins from the cell, and such impairment has been linked to AD pathogenesis. In this study, we investigated the role of cellular senescence on AD pathology by crossing a mouse model of AD-like amyloid-β (Aβ) pathology (5xFAD) with a mouse model of senescence that is genetically deficient for the RNA component of the telomerase (Terc-/-). We studied changes in amyloid pathology, neurodegeneration, and the autophagy process in brain tissue samples and primary cultures derived from these mice by complementary biochemical and immunostaining approaches. Postmortem human brain samples were also processed to evaluate autophagy defects in AD patients. Our results show that accelerated senescence produces an early accumulation of intraneuronal Aβ in the subiculum and cortical layer V of 5xFAD mice. This correlates with a reduction in amyloid plaques and Aβ levels in connecting brain regions at a later disease stage. Neuronal loss was specifically observed in brain regions presenting intraneuronal Aβ and was linked to telomere attrition. Our results indicate that senescence affects intraneuronal Aβ accumulation by impairing autophagy function and that early autophagy defects can be found in the brains of AD patients. Together, these findings demonstrate the instrumental role of senescence in intraneuronal Aβ accumulation, which represents a key event in AD pathophysiology, and emphasize the correlation between the initial stages of amyloid pathology and defects in the autophagy flux.
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Affiliation(s)
- Nuria Suelves
- Aging and Dementia Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience (IoNS), UCLouvain, Brussels, Belgium
| | - Shirine Saleki
- Aging and Dementia Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience (IoNS), UCLouvain, Brussels, Belgium
| | - Tasha Ibrahim
- Aging and Dementia Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience (IoNS), UCLouvain, Brussels, Belgium
| | - Debora Palomares
- Aging and Dementia Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience (IoNS), UCLouvain, Brussels, Belgium
| | - Sebastiaan Moonen
- Laboratory for Neuropathology, Department of Imaging and Pathology, Leuven Brain Institute (LBI), KU Leuven, Leuven, Belgium
- Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, Leuven, Belgium
- Vlaams Instituut Voor Biotechnologie (VIB) Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Marta J Koper
- Laboratory for Neuropathology, Department of Imaging and Pathology, Leuven Brain Institute (LBI), KU Leuven, Leuven, Belgium
- Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, Leuven, Belgium
- Vlaams Instituut Voor Biotechnologie (VIB) Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Céline Vrancx
- Aging and Dementia Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience (IoNS), UCLouvain, Brussels, Belgium
- Laboratory for Membrane Trafficking, Department of Neurosciences, Vlaams Instituut Voor Biotechnologie (VIB) Center for Brain and Disease Research, KU Leuven, Leuven, Belgium
| | - Devkee M Vadukul
- Aging and Dementia Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience (IoNS), UCLouvain, Brussels, Belgium
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, London, UK
| | - Nicolas Papadopoulos
- Ludwig Institute for Cancer Research, Brussels, Belgium
- SIGN Unit, de Duve Institute, UCLouvain, Brussels, Belgium
| | - Nikenza Viceconte
- Genetic and Epigenetic Alterations of Genomes Unit, de Duve Institute, UCLouvain, Brussels, Belgium
- CENTOGENE GmbH, 18055, Rostock, Germany
| | - Eloïse Claude
- Genetic and Epigenetic Alterations of Genomes Unit, de Duve Institute, UCLouvain, Brussels, Belgium
| | - Rik Vandenberghe
- Laboratory for Cognitive Neurology, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven (University of Leuven), Leuven, Belgium
- Department of Neurology, University Hospital Leuven, Leuven, Belgium
| | - Christine A F von Arnim
- Department of Neurology, University of Ulm, Ulm, Germany
- Department of Geriatrics, University Medical Center Göttingen, Göttingen, Germany
| | - Stefan N Constantinescu
- Ludwig Institute for Cancer Research, Brussels, Belgium
- SIGN Unit, de Duve Institute, UCLouvain, Brussels, Belgium
- Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Brussels, Belgium
- Nuffield Department of Medicine, Ludwig Institute for Cancer Research, Oxford University, Oxford, UK
| | - Dietmar Rudolf Thal
- Laboratory for Neuropathology, Department of Imaging and Pathology, Leuven Brain Institute (LBI), KU Leuven, Leuven, Belgium
- Department of Pathology, University Hospital Leuven, Leuven, Belgium
| | - Anabelle Decottignies
- Genetic and Epigenetic Alterations of Genomes Unit, de Duve Institute, UCLouvain, Brussels, Belgium
| | - Pascal Kienlen-Campard
- Aging and Dementia Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience (IoNS), UCLouvain, Brussels, Belgium.
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6
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Papadopoulos N, Suelves N, Perrin F, Vadukul DM, Vrancx C, Constantinescu SN, Kienlen-Campard P. Structural Determinant of β-Amyloid Formation: From Transmembrane Protein Dimerization to β-Amyloid Aggregates. Biomedicines 2022; 10:2753. [PMID: 36359274 PMCID: PMC9687742 DOI: 10.3390/biomedicines10112753] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 10/18/2022] [Accepted: 10/21/2022] [Indexed: 10/03/2023] Open
Abstract
Most neurodegenerative diseases have the characteristics of protein folding disorders, i.e., they cause lesions to appear in vulnerable regions of the nervous system, corresponding to protein aggregates that progressively spread through the neuronal network as the symptoms progress. Alzheimer's disease is one of these diseases. It is characterized by two types of lesions: neurofibrillary tangles (NFTs) composed of tau proteins and senile plaques, formed essentially of amyloid peptides (Aβ). A combination of factors ranging from genetic mutations to age-related changes in the cellular context converge in this disease to accelerate Aβ deposition. Over the last two decades, numerous studies have attempted to elucidate how structural determinants of its precursor (APP) modify Aβ production, and to understand the processes leading to the formation of different Aβ aggregates, e.g., fibrils and oligomers. The synthesis proposed in this review indicates that the same motifs can control APP function and Aβ production essentially by regulating membrane protein dimerization, and subsequently Aβ aggregation processes. The distinct properties of these motifs and the cellular context regulate the APP conformation to trigger the transition to the amyloid pathology. This concept is critical to better decipher the patterns switching APP protein conformation from physiological to pathological and improve our understanding of the mechanisms underpinning the formation of amyloid fibrils that devastate neuronal functions.
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Affiliation(s)
- Nicolas Papadopoulos
- SIGN Unit, de Duve Institute, UCLouvain, 1200 Brussels, Belgium
- Ludwig Institute for Cancer Research Brussels, 1348 Brussels, Belgium
| | - Nuria Suelves
- Aging and Dementia Research Group, Cellular and Molecular (CEMO) Division, Institute of Neuroscience, UCLouvain, 1200 Brussels, Belgium
| | - Florian Perrin
- Memory Disorders Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Devkee M. Vadukul
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, London SW7 2BX, UK
| | - Céline Vrancx
- Laboratory for Membrane Trafficking, VIB-Center for Brain and Disease Research, KU Leuven, 3000 Leuven, Belgium
- Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium
| | - Stefan N. Constantinescu
- SIGN Unit, de Duve Institute, UCLouvain, 1200 Brussels, Belgium
- Ludwig Institute for Cancer Research Brussels, 1348 Brussels, Belgium
- Walloon Excellence in Life Sciences and Biotechnology (WELBIO), 1300 Wavre, Belgium
- Nuffield Department of Medicine, Ludwig Institute for Cancer Research, Oxford University, Oxford OX1 2JD, UK
| | - Pascal Kienlen-Campard
- Aging and Dementia Research Group, Cellular and Molecular (CEMO) Division, Institute of Neuroscience, UCLouvain, 1200 Brussels, Belgium
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7
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Cho Y, Bae HG, Okun E, Arumugam TV, Jo DG. Physiology and pharmacology of amyloid precursor protein. Pharmacol Ther 2022; 235:108122. [PMID: 35114285 DOI: 10.1016/j.pharmthera.2022.108122] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 01/17/2022] [Accepted: 01/25/2022] [Indexed: 02/06/2023]
Abstract
Amyloid precursor protein (APP) is an evolutionarily conserved transmembrane protein and a well-characterized precursor protein of amyloid-beta (Aβ) peptides, which accumulate in the brains of individuals with Alzheimer's disease (AD)-related pathologies. Aβ has been extensively investigated since the amyloid hypothesis in AD was proposed. Besides Aβ, previous studies on APP and its proteolytic cleavage products have suggested their diverse pathological and physiological functions. However, their roles still have not been thoroughly understood. In this review, we extensively discuss the evolutionarily-conserved biology of APP, including its structure and processing pathway, as well as recent findings on the physiological roles of APP and its fragments in the central nervous system and peripheral nervous system. We have also elaborated upon the current status of APP-targeted therapeutic approaches for AD treatment by discussing inhibitors of several proteases participating in APP processing, including α-, β-, and γ-secretases. Finally, we have highlighted the future perspectives pertaining to further research and the potential clinical role of APP.
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Affiliation(s)
- Yoonsuk Cho
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, South Korea
| | - Han-Gyu Bae
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, South Korea
| | - Eitan Okun
- The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan 5290002, Israel; The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel; The Pauld Feder Laboratory on Alzheimer's Disease Research, Israel
| | - Thiruma V Arumugam
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, South Korea; School of Life Sciences, La Trobe University, Bundoora, Victoria, Australia.
| | - Dong-Gyu Jo
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, South Korea; Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 06351, South Korea; Biomedical Institute for Convergence, Sungkyunkwan University, Suwon 16419, South Korea.
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8
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Gabriele RMC, Abel E, Fox NC, Wray S, Arber C. Knockdown of Amyloid Precursor Protein: Biological Consequences and Clinical Opportunities. Front Neurosci 2022; 16:835645. [PMID: 35360155 PMCID: PMC8964081 DOI: 10.3389/fnins.2022.835645] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 02/18/2022] [Indexed: 12/29/2022] Open
Abstract
Amyloid precursor protein (APP) and its cleavage fragment Amyloid-β (Aβ) have fundamental roles in Alzheimer's disease (AD). Genetic alterations that either increase the overall dosage of APP or alter its processing to favour the generation of longer, more aggregation prone Aβ species, are directly causative of the disease. People living with one copy of APP are asymptomatic and reducing APP has been shown to lower the relative production of aggregation-prone Aβ species in vitro. For these reasons, reducing APP expression is an attractive approach for AD treatment and prevention. In this review, we will describe the structure and the known functions of APP and go on to discuss the biological consequences of APP knockdown and knockout in model systems. We highlight progress in therapeutic strategies to reverse AD pathology via reducing APP expression. We conclude that new technologies that reduce the dosage of APP expression may allow disease modification and slow clinical progression, delaying or even preventing onset.
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Affiliation(s)
- Rebecca M. C. Gabriele
- Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Emily Abel
- Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, London, United Kingdom,UK Dementia Research Institute at University College London (UCL), Queen Square Institute of Neurology, London, United Kingdom
| | - Nick C. Fox
- Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, London, United Kingdom,UK Dementia Research Institute at University College London (UCL), Queen Square Institute of Neurology, London, United Kingdom
| | - Selina Wray
- Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Charles Arber
- Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, London, United Kingdom,*Correspondence: Charles Arber,
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9
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Cha HJ, Shen J, Kang J. Regulation of gene expression by the APP family in the adult cerebral cortex. Sci Rep 2022; 12:66. [PMID: 34997052 PMCID: PMC8741778 DOI: 10.1038/s41598-021-04027-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 12/14/2021] [Indexed: 12/13/2022] Open
Abstract
Amyloid precursor protein (APP) is associated with both familial and sporadic forms of Alzheimer's disease. APP has two homologs, amyloid precursor-like protein 1 and 2 (APLP1 and APLP2), and they have functional redundancy. APP intracellular c-terminal domain (AICD), produced by sequential α- or β- and γ-secretase cleavages, is thought to control gene expression, similarly as the ICD of Notch. To investigate the role of APP family in transcriptional regulation, we examined gene expression changes in the cerebral cortex of APP/APLP1/APLP2 conditional triple knockout (cTKO) mice, in which APP family members are selectively inactivated in excitatory neurons of the postnatal forebrain. Of the 12 previously reported AICD target genes, only Nep and Npas4 mRNA levels were significantly reduced in the cerebral cortex of cTKO mice, compared to littermate controls. We further examined global transcriptional changes by RNA-seq and identified 189 and 274 differentially expressed genes in the neocortex and hippocampus, respectively, of cTKO mice relative to controls. Gene Ontology analysis indicated that these genes are involved in a variety of cellular functions, including extracellular organization, learning and memory, and ion channels. Thus, inactivation of APP family alters transcriptional profiles of the cerebral cortex and affects wide-ranging molecular pathways.
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Affiliation(s)
- Hye Ji Cha
- Division of Hematology/Oncology, Boston Children's Hospital and Department of Pediatric Oncology, Dana-Farber Cancer Institute (DFCI), Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, 02115, USA
| | - Jie Shen
- Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
- Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA
| | - Jongkyun Kang
- Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
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10
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Vrancx C, Vadukul DM, Suelves N, Contino S, D'Auria L, Perrin F, van Pesch V, Hanseeuw B, Quinton L, Kienlen-Campard P. Mechanism of Cellular Formation and In Vivo Seeding Effects of Hexameric β-Amyloid Assemblies. Mol Neurobiol 2021; 58:6647-6669. [PMID: 34608607 PMCID: PMC8639606 DOI: 10.1007/s12035-021-02567-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 09/14/2021] [Indexed: 12/21/2022]
Abstract
The β-amyloid peptide (Aβ) is found as amyloid fibrils in senile plaques, a typical hallmark of Alzheimer's disease (AD). However, intermediate soluble oligomers of Aβ are now recognized as initiators of the pathogenic cascade leading to AD. Studies using recombinant Aβ have shown that hexameric Aβ in particular acts as a critical nucleus for Aβ self-assembly. We recently isolated hexameric Aβ assemblies from a cellular model, and demonstrated their ability to enhance Aβ aggregation in vitro. Here, we report the presence of similar hexameric-like Aβ assemblies across several cellular models, including neuronal-like cell lines. In order to better understand how they are produced in a cellular context, we investigated the role of presenilin-1 (PS1) and presenilin-2 (PS2) in their formation. PS1 and PS2 are the catalytic subunits of the γ-secretase complex that generates Aβ. Using CRISPR-Cas9 to knockdown each of the two presenilins in neuronal-like cell lines, we observed a direct link between the PS2-dependent processing pathway and the release of hexameric-like Aβ assemblies in extracellular vesicles. Further, we assessed the contribution of hexameric Aβ to the development of amyloid pathology. We report the early presence of hexameric-like Aβ assemblies in both transgenic mice brains exhibiting human Aβ pathology and in the cerebrospinal fluid of AD patients, suggesting hexameric Aβ as a potential early AD biomarker. Finally, cell-derived hexameric Aβ was found to seed other human Aβ forms, resulting in the aggravation of amyloid deposition in vivo and neuronal toxicity in vitro.
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Affiliation(s)
- Céline Vrancx
- Alzheimer Research Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, 1200, Brussels, Belgium
| | - Devkee M Vadukul
- Alzheimer Research Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, 1200, Brussels, Belgium
| | - Nuria Suelves
- Alzheimer Research Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, 1200, Brussels, Belgium
| | - Sabrina Contino
- Alzheimer Research Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, 1200, Brussels, Belgium
| | - Ludovic D'Auria
- Neurochemistry Unit, Cellular and Molecular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, 1200, Brussels, Belgium
| | - Florian Perrin
- Alzheimer Research Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, 1200, Brussels, Belgium
| | - Vincent van Pesch
- Neurochemistry Unit, Cellular and Molecular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, 1200, Brussels, Belgium
| | - Bernard Hanseeuw
- Department of Neurology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, 1200, Brussels, Belgium
| | - Loïc Quinton
- Laboratory of Mass Spectrometry, Department of Chemistry, Université de Liège, 4000, Liège, Belgium
| | - Pascal Kienlen-Campard
- Alzheimer Research Group, Cellular and Molecular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, 1200, Brussels, Belgium.
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11
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Kreis A, Desloovere J, Suelves N, Pierrot N, Yerna X, Issa F, Schakman O, Gualdani R, de Clippele M, Tajeddine N, Kienlen-Campard P, Raedt R, Octave JN, Gailly P. Overexpression of wild-type human amyloid precursor protein alters GABAergic transmission. Sci Rep 2021; 11:17600. [PMID: 34475508 PMCID: PMC8413381 DOI: 10.1038/s41598-021-97144-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 08/13/2021] [Indexed: 02/07/2023] Open
Abstract
The function of the amyloid precursor protein (APP) is not fully understood, but its cleavage product amyloid beta (Aβ) together with neurofibrillary tangles constitute the hallmarks of Alzheimer's disease (AD). Yet, imbalance of excitatory and inhibitory neurotransmission accompanied by loss of synaptic functions, has been reported much earlier and independent of any detectable pathological markers. Recently, soluble APP fragments have been shown to bind to presynaptic GABAB receptors (GABABRs), subsequently decreasing the probability of neurotransmitter release. In this body of work, we were able to show that overexpression of wild-type human APP in mice (hAPPwt) causes early cognitive impairment, neuronal loss, and electrophysiological abnormalities in the absence of amyloid plaques and at very low levels of Aβ. hAPPwt mice exhibited neuronal overexcitation that was evident in EEG and increased long-term potentiation (LTP). Overexpression of hAPPwt did not alter GABAergic/glutamatergic receptor components or GABA production ability. Nonetheless, we detected a decrease of GABA but not glutamate that could be linked to soluble APP fragments, acting on presynaptic GABABRs and subsequently reducing GABA release. By using a specific presynaptic GABABR antagonist, we were able to rescue hyperexcitation in hAPPwt animals. Our results provide evidence that APP plays a crucial role in regulating inhibitory neurotransmission.
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Affiliation(s)
- Anna Kreis
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Jana Desloovere
- grid.5342.00000 0001 2069 7798Faculty of Medicine and Health Sciences, Universiteit Gent, C. Heymanslaan 10, 9000 Gent, Belgium
| | - Nuria Suelves
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Nathalie Pierrot
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Xavier Yerna
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Farah Issa
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Olivier Schakman
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Roberta Gualdani
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Marie de Clippele
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Nicolas Tajeddine
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Pascal Kienlen-Campard
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Robrecht Raedt
- grid.5342.00000 0001 2069 7798Faculty of Medicine and Health Sciences, Universiteit Gent, C. Heymanslaan 10, 9000 Gent, Belgium
| | - Jean-Noël Octave
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Philippe Gailly
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
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12
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Onodera W, Asahi T, Sawamura N. Rapid evolution of mammalian APLP1 as a synaptic adhesion molecule. Sci Rep 2021; 11:11305. [PMID: 34050225 PMCID: PMC8163877 DOI: 10.1038/s41598-021-90737-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 05/17/2021] [Indexed: 01/10/2023] Open
Abstract
Amyloid precursor protein (APP) family members are involved in essential neuronal development including neurite outgrowth, neuronal migration and maturation of synapse and neuromuscular junction. Among the APP gene family members, amyloid precursor-like protein 1 (APLP1) is selectively expressed in neurons and has specialized functions during synaptogenesis. Although a potential role for APLP1 in neuronal evolution has been indicated, its precise evolutionary and functional contributions are unknown. This study shows the molecular evolution of the vertebrate APP family based on phylogenetic analysis, while contrasting the evolutionary differences within the APP family. Phylogenetic analysis showed 15 times higher substitution rate that is driven by positive selection at the stem branch of the mammalian APLP1, resulting in dissimilar protein sequences compared to APP/APLP2. Docking simulation identified one positively selected site in APLP1 that alters the heparin-binding site, which could affect its function, and dimerization rate. Furthermore, the evolutionary rate covariation between the mammalian APP family and synaptic adhesion molecules (SAMs) was confirmed, indicating that only APLP1 has evolved to gain synaptic adhesion property. Overall, our results suggest that the enhanced synaptogenesis property of APLP1 as one of the SAMs may have played a role in mammalian brain evolution.
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Affiliation(s)
- Wataru Onodera
- Faculty of Science and Engineering, Waseda University, TWIns, 2-2 Wakamatsu, Shinjuku, Tokyo, 162-8480, Japan
| | - Toru Asahi
- Faculty of Science and Engineering, Waseda University, TWIns, 2-2 Wakamatsu, Shinjuku, Tokyo, 162-8480, Japan.,Research Organization for Nano & Life Innovation, Waseda University, #03C309, TWIns, 2-2 Wakamatsu, Shinjuku, Tokyo, 162-8480, Japan
| | - Naoya Sawamura
- Research Organization for Nano & Life Innovation, Waseda University, #03C309, TWIns, 2-2 Wakamatsu, Shinjuku, Tokyo, 162-8480, Japan. .,Green Computing Systems Research Organization, Waseda University, Shinjuku, Japan.
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13
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Cejas RB, Tamaño-Blanco M, Blanco JG. Analysis of the intracellular traffic of IgG in the context of Down syndrome (trisomy 21). Sci Rep 2021; 11:10981. [PMID: 34040082 PMCID: PMC8155081 DOI: 10.1038/s41598-021-90469-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 05/10/2021] [Indexed: 12/21/2022] Open
Abstract
Persons with Down syndrome (DS, trisomy 21) have widespread cellular protein trafficking defects. There is a paucity of data describing the intracellular transport of IgG in the context of endosomal-lysosomal alterations linked to trisomy 21. In this study, we analyzed the intracellular traffic of IgG mediated by the human neonatal Fc receptor (FcRn) in fibroblast cell lines with trisomy 21. Intracellular IgG trafficking studies in live cells showed that fibroblasts with trisomy 21 exhibit higher proportion of IgG in lysosomes (~ 10% increase), decreased IgG content in intracellular vesicles (~ 9% decrease), and a trend towards decreased IgG recycling (~ 55% decrease) in comparison to diploid cells. Amyloid-beta precursor protein (APP) overexpression in diploid fibroblasts replicated the increase in IgG sorting to the degradative pathway observed in cells with trisomy 21. The impact of APP on the expression of FCGRT (alpha chain component of FcRn) was investigated by APP knock down and overexpression of the APP protein. APP knock down increased the expression of FCGRT mRNA by ~ 60% in both diploid and trisomic cells. Overexpression of APP in diploid fibroblasts and HepG2 cells resulted in a decrease in FCGRT and FcRn expression. Our results indicate that the intracellular traffic of IgG is altered in cells with trisomy 21. This study lays the foundation for future investigations into the role of FcRn in the context of DS.
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Affiliation(s)
- R B Cejas
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, 470 Pharmacy Building, Buffalo, NY, 14214-8033, USA
| | - M Tamaño-Blanco
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, 470 Pharmacy Building, Buffalo, NY, 14214-8033, USA
| | - J G Blanco
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, 470 Pharmacy Building, Buffalo, NY, 14214-8033, USA.
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14
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Contino S, Suelves N, Vrancx C, Vadukul DM, Payen VL, Stanga S, Bertrand L, Kienlen-Campard P. Presenilin-Deficient Neurons and Astrocytes Display Normal Mitochondrial Phenotypes. Front Neurosci 2021; 14:586108. [PMID: 33551720 PMCID: PMC7862347 DOI: 10.3389/fnins.2020.586108] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 12/14/2020] [Indexed: 01/13/2023] Open
Abstract
Presenilin 1 (PS1) and Presenilin 2 (PS2) are predominantly known as the catalytic subunits of the γ-secretase complex that generates the amyloid-β (Aβ) peptide, the major constituent of the senile plaques found in the brain of Alzheimer's disease (AD) patients. Apart from their role in γ-secretase activity, a growing number of cellular functions have been recently attributed to PSs. Notably, PSs were found to be enriched in mitochondria-associated membranes (MAMs) where mitochondria and endoplasmic reticulum (ER) interact. PS2 was more specifically reported to regulate calcium shuttling between these two organelles by controlling the formation of functional MAMs. We have previously demonstrated in mouse embryonic fibroblasts (MEF) an altered mitochondrial morphology along with reduced mitochondrial respiration and increased glycolysis in PS2-deficient cells (PS2KO). This phenotype was restored by the stable re-expression of human PS2. Still, all these results were obtained in immortalized cells, and one bottom-line question is to know whether these observations hold true in central nervous system (CNS) cells. To that end, we carried out primary cultures of PS1 knockdown (KD), PS2KO, and PS1KD/PS2KO (PSdKO) neurons and astrocytes. They were obtained from the same litter by crossing PS2 heterozygous; PS1 floxed (PS2+/-; PS1flox/flox) animals. Genetic downregulation of PS1 was achieved by lentiviral expression of the Cre recombinase in primary cultures. Strikingly, we did not observe any mitochondrial phenotype in PS1KD, PS2KO, or PSdKO primary cultures in basal conditions. Mitochondrial respiration and membrane potential were similar in all models, as were the glycolytic flux and NAD+/NADH ratio. Likewise, mitochondrial morphology and content was unaltered by PS expression. We further investigated the differences between results we obtained here in primary nerve cells and those previously reported in MEF cell lines by analyzing PS2KO primary fibroblasts. We found no mitochondrial dysfunction in this model, in line with observations in PS2KO primary neurons and astrocytes. Together, our results indicate that the mitochondrial phenotype observed in immortalized PS2-deficient cell lines cannot be extrapolated to primary neurons, astrocytes, and even to primary fibroblasts. The PS-dependent mitochondrial phenotype reported so far might therefore be the consequence of a cell immortalization process and should be critically reconsidered regarding its relevance to AD.
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Affiliation(s)
- Sabrina Contino
- Alzheimer Research Group, Molecular and Cellular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Nuria Suelves
- Alzheimer Research Group, Molecular and Cellular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Céline Vrancx
- Alzheimer Research Group, Molecular and Cellular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Devkee M. Vadukul
- Alzheimer Research Group, Molecular and Cellular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Valery L. Payen
- Laboratory of Advanced Drug Delivery and Biomaterial (ADDB), Louvain Drug Research Institute (LDRI), Université Catholique de Louvain, Brussels, Belgium
| | - Serena Stanga
- Neuroscience Institute Cavalieri Ottolenghi, Department of Neuroscience, University of Torino, Torino, Italy
| | - Luc Bertrand
- Pole of Cardiovascular Research, Institute of Experimental and Clinical Research, Université Catholique de Louvain, Brussels, Belgium
| | - Pascal Kienlen-Campard
- Alzheimer Research Group, Molecular and Cellular Division (CEMO), Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
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15
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Fu J, Guo O, Zhen Z, Zhen J. Essential Functions of the Transcription Factor Npas4 in Neural Circuit Development, Plasticity, and Diseases. Front Neurosci 2020; 14:603373. [PMID: 33335473 PMCID: PMC7736240 DOI: 10.3389/fnins.2020.603373] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 11/11/2020] [Indexed: 12/13/2022] Open
Abstract
Signaling from the synapse to nucleus is mediated by the integration and propagation of both membrane potential changes (postsynaptic potentials) and intracellular second messenger cascades. The electrical propagation of postsynaptic potentials allows for rapid neural information processing, while propagating second messenger pathways link synaptic activity to the transcription of genes required for neuronal survival and adaptive changes (plasticity) underlying circuit formation and learning. The propagation of activity-induced calcium signals to the cell nucleus is a major synapse-to-nucleus communication pathway. Neuronal PAS domain protein 4 (Npas4) is a recently discovered calcium-dependent transcription factor that regulates the activation of genes involved in the homeostatic regulation of excitatory–inhibitory balance, which is critical for neural circuit formation, function, and ongoing plasticity, as well as for defense against diseases such as epilepsy. Here, we summarize recent findings on the neuroprotective functions of Npas4 and the potential of Npas4 as a therapeutic target for the treatment of acute and chronic diseases of the central nervous system.
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Affiliation(s)
- Jian Fu
- Department of Emergency Surgery, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Ouyang Guo
- Department of Biology, Boston University, Boston, MA, United States
| | - Zhihang Zhen
- Department of Neurology, Key Laboratory of Neurology of Hebei Province, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Junli Zhen
- Department of Neurology, Key Laboratory of Neurology of Hebei Province, The Second Hospital of Hebei Medical University, Shijiazhuang, China
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16
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Kozlova I, Sah S, Keable R, Leshchyns'ka I, Janitz M, Sytnyk V. Cell Adhesion Molecules and Protein Synthesis Regulation in Neurons. Front Mol Neurosci 2020; 13:592126. [PMID: 33281551 PMCID: PMC7689008 DOI: 10.3389/fnmol.2020.592126] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 10/16/2020] [Indexed: 12/18/2022] Open
Abstract
Cell adhesion molecules (CAMs) mediate interactions of neurons with the extracellular environment by forming adhesive bonds with CAMs on adjacent membranes or via binding to proteins of the extracellular matrix. Binding of CAMs to their extracellular ligands results in the activation of intracellular signaling cascades, leading to changes in neuronal structure and the molecular composition and function of neuronal contacts. Ultimately, many of these changes depend on the synthesis of new proteins. In this review, we summarize the evidence showing that CAMs regulate protein synthesis by modulating the activity of transcription factors, gene expression, protein translation, and the structure and distribution of organelles involved in protein synthesis and transport.
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Affiliation(s)
- Irina Kozlova
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Saroj Sah
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Ryan Keable
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Iryna Leshchyns'ka
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Michael Janitz
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Vladimir Sytnyk
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
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17
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Probst S, Krüger M, Kägi L, Thöni S, Schuppli D, Nitsch RM, Konietzko U. Fe65 is the sole member of its family that mediates transcription regulated by the amyloid precursor protein. J Cell Sci 2020; 133:jcs242917. [PMID: 32843577 DOI: 10.1242/jcs.242917] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Accepted: 07/11/2020] [Indexed: 08/31/2023] Open
Abstract
The amyloid precursor protein (APP), a central molecule in Alzheimer's disease (AD), has physiological roles in cell adhesion and signaling, migration, neurite outgrowth and synaptogenesis. Intracellular adapter proteins mediate the function of transmembrane proteins. Fe65 (also known as APBB1) is a major APP-binding protein. Regulated intramembrane proteolysis (RIP) by γ-secretase releases the APP intracellular domain (AICD), together with the interacting proteins, from the membrane. We studied the impact of the Fe65 family (Fe65, and its homologs Fe65L1 and Fe65L2, also known as APBB2 and APBB3, respectively) on the nuclear signaling function of the AICD. All Fe65 family members increased amyloidogenic processing of APP, generating higher levels of β-cleaved APP stubs and AICD. However, Fe65 was the only family member supporting AICD translocation to nuclear spots and its transcriptional activity. Using a recently established transcription assay, we dissected the transcriptional activity of Fe65 and provide strong evidence that Fe65 represents a transcription factor. We show that Fe65 relies on the lysine acetyltransferase Tip60 (also known as KAT5) for nuclear translocation. Furthermore, inhibition of APP cleavage reduces nuclear Tip60 levels, but this does not occur in Fe65-knockout cells. The rate of APP cleavage therefore regulates the nuclear translocation of AICD-Fe65-Tip60 (AFT) complexes, to promote transcription by Fe65.
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Affiliation(s)
- Sabine Probst
- Institute for Regenerative Medicine - IREM, University of Zurich, Campus Schlieren, Wagistrasse 12, 8952 Schlieren - Zurich, Switzerland
| | - Maik Krüger
- Institute for Regenerative Medicine - IREM, University of Zurich, Campus Schlieren, Wagistrasse 12, 8952 Schlieren - Zurich, Switzerland
| | - Larissa Kägi
- Institute for Regenerative Medicine - IREM, University of Zurich, Campus Schlieren, Wagistrasse 12, 8952 Schlieren - Zurich, Switzerland
| | - Sarina Thöni
- Institute for Regenerative Medicine - IREM, University of Zurich, Campus Schlieren, Wagistrasse 12, 8952 Schlieren - Zurich, Switzerland
| | - Daniel Schuppli
- Institute for Regenerative Medicine - IREM, University of Zurich, Campus Schlieren, Wagistrasse 12, 8952 Schlieren - Zurich, Switzerland
| | - Roger M Nitsch
- Institute for Regenerative Medicine - IREM, University of Zurich, Campus Schlieren, Wagistrasse 12, 8952 Schlieren - Zurich, Switzerland
| | - Uwe Konietzko
- Institute for Regenerative Medicine - IREM, University of Zurich, Campus Schlieren, Wagistrasse 12, 8952 Schlieren - Zurich, Switzerland
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18
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Poon CH, Tse LSR, Lim LW. DNA methylation in the pathology of Alzheimer's disease: from gene to cognition. Ann N Y Acad Sci 2020; 1475:15-33. [PMID: 32491215 DOI: 10.1111/nyas.14373] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 04/16/2020] [Accepted: 04/24/2020] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD) is a debilitating disorder that manifests with amyloid beta plaque deposition, neurofibrillary tangles, neuronal loss, and severe cognitive impairment. Although much effort has been made to decipher the pathogenesis of this disease, the mechanisms causing these detrimental outcomes remain obscure. Over the past few decades, neuroepigenetics has emerged as an important field that, among other things, explores how reversible modifications can change gene expression to control behavior and cognitive abilities. Among epigenetic modifications, DNA methylation requires further elucidation for the conflicting observations from AD research and its pivotal role in learning and memory. In this review, we focus on the essential components of DNA methylation, the effects of aberrant methylation on gene expressions in the amyloidogenic pathway and neurochemical processes, as well as memory epigenetics in Alzheimer's disease.
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Affiliation(s)
- Chi Him Poon
- Neuromodulation Laboratory, Li Ka Shing Faculty of Medicine, School of Biomedical Sciences, the University of Hong Kong, Hong Kong, P. R. China
| | - Long Sum Rachel Tse
- Neuromodulation Laboratory, Li Ka Shing Faculty of Medicine, School of Biomedical Sciences, the University of Hong Kong, Hong Kong, P. R. China
| | - Lee Wei Lim
- Neuromodulation Laboratory, Li Ka Shing Faculty of Medicine, School of Biomedical Sciences, the University of Hong Kong, Hong Kong, P. R. China
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