1
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Arias-Aragón F, Tristán-Clavijo E, Martínez-Gallego I, Robles-Lanuza E, Coatl-Cuaya H, Martín-Cuevas C, Sánchez-Hidalgo AC, Rodríguez-Moreno A, Martinez-Mir A, Scholl FG. A Neuroligin-1 mutation associated with Alzheimer's disease produces memory and age-dependent impairments in hippocampal plasticity. iScience 2023; 26:106868. [PMID: 37260747 PMCID: PMC10227424 DOI: 10.1016/j.isci.2023.106868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 03/31/2023] [Accepted: 05/09/2023] [Indexed: 06/02/2023] Open
Abstract
Alzheimer's disease (AD) is characterized by memory impairments and age-dependent synapse loss. Experimental and clinical studies have shown decreased expression of the glutamatergic protein Neuroligin-1 (Nlgn1) in AD. However, the consequences of a sustained reduction of Nlgn1 are unknown. Here, we generated a knockin mouse that reproduces the NLGN1 Thr271fs mutation, identified in heterozygosis in a familial case of AD. We found that Nlgn1 Thr271fs mutation abolishes Nlgn1 expression in mouse brain. Importantly, heterozygous Nlgn1 Thr271fs mice showed delay-dependent amnesia for recognition memory. Electrophysiological recordings uncovered age-dependent impairments in basal synaptic transmission and long-term potentiation (LTP) in CA1 hippocampal neurons of heterozygous Nlgn1 Thr271fs mice. In contrast, homozygous Nlgn1 Thr271fs mice showed impaired fear-conditioning memory and normal basal synaptic transmission, suggesting unshared mechanisms for a partial or total loss of Nlgn1. These data suggest that decreased Nlgn1 may contribute to the synaptic and memory deficits in AD.
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Affiliation(s)
- Francisco Arias-Aragón
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, 41009 Seville, Spain
| | - Enriqueta Tristán-Clavijo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
| | - Irene Martínez-Gallego
- Laboratory of Cellular Neuroscience and Plasticity, Department of Physiology, Anatomy and Cell Biology, University Pablo de Olavide, 41013 Seville, Spain
| | - Estefanía Robles-Lanuza
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, 41009 Seville, Spain
| | - Heriberto Coatl-Cuaya
- Laboratory of Cellular Neuroscience and Plasticity, Department of Physiology, Anatomy and Cell Biology, University Pablo de Olavide, 41013 Seville, Spain
| | - Celia Martín-Cuevas
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, 41009 Seville, Spain
| | - Ana C. Sánchez-Hidalgo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, 41009 Seville, Spain
| | - Antonio Rodríguez-Moreno
- Laboratory of Cellular Neuroscience and Plasticity, Department of Physiology, Anatomy and Cell Biology, University Pablo de Olavide, 41013 Seville, Spain
| | - Amalia Martinez-Mir
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
| | - Francisco G. Scholl
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, 41009 Seville, Spain
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2
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Peng L, Baradar AA, Aguado J, Wolvetang E. Cellular senescence and premature aging in Down Syndrome. Mech Ageing Dev 2023; 212:111824. [PMID: 37236373 DOI: 10.1016/j.mad.2023.111824] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 05/15/2023] [Accepted: 05/23/2023] [Indexed: 05/28/2023]
Abstract
Down syndrome (DS) is a genetic disorder caused by an extra copy of chromosome 21, resulting in cognitive impairment, physical abnormalities, and an increased risk of age-related co-morbidities. Individuals with DS exhibit accelerated aging, which has been attributed to several cellular mechanisms, including cellular senescence, a state of irreversible cell cycle arrest that is associated with aging and age-related diseases. Emerging evidence suggests that cellular senescence may play a key role in the pathogenesis of DS and the development of age-related disorders in this population. Importantly, cellular senescence may be a potential therapeutic target in alleviating age-related DS pathology. Here, we discuss the importance of focusing on cellular senescence to understand accelerated aging in DS. We review the current state of knowledge regarding cellular senescence and other hallmarks of aging in DS, including its putative contribution to cognitive impairment, multi-organ dysfunction, and premature aging phenotypes.
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Affiliation(s)
- Lianli Peng
- Australian Institute for Biotechnology and Nanotechnology, University of Queensland, St Lucia, QLD 4072, Australia
| | - Alireza A Baradar
- Australian Institute for Biotechnology and Nanotechnology, University of Queensland, St Lucia, QLD 4072, Australia
| | - Julio Aguado
- Australian Institute for Biotechnology and Nanotechnology, University of Queensland, St Lucia, QLD 4072, Australia.
| | - Ernst Wolvetang
- Australian Institute for Biotechnology and Nanotechnology, University of Queensland, St Lucia, QLD 4072, Australia.
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3
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Tovar ÁE, Torres-Chávez Á, Mofrad AA, Arntzen E. Computational models of stimulus equivalence: An intersection for the study of symbolic behavior. J Exp Anal Behav 2023; 119:407-425. [PMID: 36752316 DOI: 10.1002/jeab.829] [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] [Received: 03/11/2022] [Accepted: 12/21/2022] [Indexed: 02/09/2023]
Abstract
Stimulus equivalence is a central paradigm in the analysis of symbolic behavior, language, and cognition. It describes emergent relations between stimuli that were not explicitly trained and cannot be explained by primary stimulus generalization. In recent years, researchers have developed computational models to simulate the learning of equivalence relations. These models have been used to address primary theoretical and methodological issues in this field, such as exploring the underlying mechanisms that explain emergent equivalence relations and analyzing the effects of training and testing protocols on equivalence outcomes. Nonetheless, although these models build upon general learning principles, their operation is usually obscure for nonmodelers, and in the field of stimulus equivalence computational models have been developed with a variety of approaches, architectures, and algorithms that make it difficult to understand the scope and contributions of these tools. In this paper, we present the state of the art in computational modeling of stimulus equivalence. We seek to provide concise and accessible descriptions of the models' functioning and operation, highlight their main theoretical and methodological contributions, identify the existing software available for researchers to run experiments, and suggest future directions in the emergent field of computational modeling of stimulus equivalence.
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Affiliation(s)
| | | | - Asieh Abolpour Mofrad
- Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
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4
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Tovar ÁE, Westermann G. No need to forget, just keep the balance: Hebbian neural networks for statistical learning. Cognition 2023; 230:105176. [PMID: 36442955 DOI: 10.1016/j.cognition.2022.105176] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 04/15/2022] [Accepted: 05/16/2022] [Indexed: 11/27/2022]
Abstract
Language processing in humans has long been proposed to rely on sophisticated learning abilities including statistical learning. Endress and Johnson (E&J, 2021) recently presented a neural network model for statistical learning based on Hebbian learning principles. This model accounts for word segmentation tasks, one primary paradigm in statistical learning. In this discussion paper we review this model and compare it with the Hebbian model previously presented by Tovar and Westermann (T&W, 2017a; 2017b; 2018) that has accounted for serial reaction time tasks, cross-situational learning, and categorization paradigms, all relevant in the study of statistical learning. We discuss the similarities and differences between both models, and their key findings. From our analysis, we question the concept of "forgetting" in the model of E&J and their suggestion of considering forgetting as the critical ingredient for successful statistical learning. We instead suggest that a set of simple but well-balanced mechanisms including spreading activation, activation persistence, and synaptic weight decay, all based on biologically grounded principles, allow modeling statistical learning in Hebbian neural networks, as demonstrated in the T&W model which successfully covers learning of nonadjacent dependencies and accounts for differences between typical and atypical populations, both aspects that have not been fully demonstrated in the E&J model. We outline the main computational and theoretical differences between the E&J and T&W approaches, present new simulation results, and discuss implications for the development of a computational cognitive theory of statistical learning.
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Affiliation(s)
- Ángel Eugenio Tovar
- Facultad de Psicología, Universidad Nacional Autónoma de México, Av. Universidad 3004, 04510 Coyoacán, Mexico.
| | - Gert Westermann
- Department of Psychology, Lancaster University, Lancaster LA1 4YF, United Kingdom
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5
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Díaz A, Flores I, Treviño S. Neurotrophic fragments as therapeutic alternatives to ameliorate brain aging. Neural Regen Res 2023; 18:51-56. [PMID: 35799508 PMCID: PMC9241392 DOI: 10.4103/1673-5374.331867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Aging is a global phenomenon and a complex biological process of all living beings that introduces various changes. During this physiological process, the brain is the most affected organ due to changes in its structural and chemical functions, such as changes in plasticity and decrease in the number, diameter, length, and branching of dendrites and dendritic spines. Likewise, it presents a great reduction in volume resulting from the contraction of the gray matter. Consequently, aging can affect not only cognitive functions, including learning and memory, but also the quality of life of older people. As a result of the phenomena, various molecules with notable neuroprotective capacity have been proposed, which provide a therapeutic alternative for people under conditions of aging or some neurodegenerative diseases. It is important to indicate that in recent years the use of molecules with neurotrophic activity has shown interesting results when evaluated in in vivo models. This review aims to describe the neurotrophic potential of molecules such as resveratrol (3,5,4′-trihydroxystilbene), neurotrophins (brain-derived neurotrophic factor), and neurotrophic-type compounds such as the terminal carboxyl domain of the heavy chain of tetanus toxin, cerebrolysin, neuropeptide-12, and rapamycin. Most of these molecules have been evaluated by our research group. Studies suggest that these molecules exert an important therapeutic potential, restoring brain function in aging conditions or models of neurodegenerative diseases. Hence, our interest is in describing the current scientific evidence that supports the therapeutic potential of these molecules with active neurotrophic.
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FDA-Approved Kinase Inhibitors in Preclinical and Clinical Trials for Neurological Disorders. Pharmaceuticals (Basel) 2022; 15:ph15121546. [PMID: 36558997 PMCID: PMC9784968 DOI: 10.3390/ph15121546] [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: 10/10/2022] [Revised: 12/09/2022] [Accepted: 12/09/2022] [Indexed: 12/14/2022] Open
Abstract
Cancers and neurological disorders are two major types of diseases. We previously developed a new concept termed "Aberrant Cell Cycle Diseases" (ACCD), revealing that these two diseases share a common mechanism of aberrant cell cycle re-entry. The aberrant cell cycle re-entry is manifested as kinase/oncogene activation and tumor suppressor inactivation, which are hallmarks of both tumor growth in cancers and neuronal death in neurological disorders. Therefore, some cancer therapies (e.g., kinase inhibition, tumor suppressor elevation) can be leveraged for neurological treatments. The United States Food and Drug Administration (US FDA) has so far approved 74 kinase inhibitors, with numerous other kinase inhibitors in clinical trials, mostly for the treatment of cancers. In contrast, there are dire unmet needs of FDA-approved drugs for neurological treatments, such as Alzheimer's disease (AD), intracerebral hemorrhage (ICH), ischemic stroke (IS), traumatic brain injury (TBI), and others. In this review, we list these 74 FDA-approved kinase-targeted drugs and identify those that have been reported in preclinical and/or clinical trials for neurological disorders, with a purpose of discussing the feasibility and applicability of leveraging these cancer drugs (FDA-approved kinase inhibitors) for neurological treatments.
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7
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Bartesaghi R. Brain circuit pathology in Down syndrome: from neurons to neural networks. Rev Neurosci 2022; 34:365-423. [PMID: 36170842 DOI: 10.1515/revneuro-2022-0067] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 08/28/2022] [Indexed: 11/15/2022]
Abstract
Down syndrome (DS), a genetic pathology caused by triplication of chromosome 21, is characterized by brain hypotrophy and impairment of cognition starting from infancy. While studies in mouse models of DS have elucidated the major neuroanatomical and neurochemical defects of DS, comparatively fewer investigations have focused on the electrophysiology of the DS brain. Electrical activity is at the basis of brain functioning. Therefore, knowledge of the way in which brain circuits operate in DS is fundamental to understand the causes of behavioral impairment and devise targeted interventions. This review summarizes the state of the art regarding the electrical properties of the DS brain, starting from individual neurons and culminating in signal processing in whole neuronal networks. The reported evidence derives from mouse models of DS and from brain tissues and neurons derived from individuals with DS. EEG data recorded in individuals with DS are also provided as a key tool to understand the impact of brain circuit alterations on global brain activity.
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Affiliation(s)
- Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
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8
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Atas-Ozcan H, Brault V, Duchon A, Herault Y. Dyrk1a from Gene Function in Development and Physiology to Dosage Correction across Life Span in Down Syndrome. Genes (Basel) 2021; 12:1833. [PMID: 34828439 PMCID: PMC8624927 DOI: 10.3390/genes12111833] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/15/2021] [Accepted: 11/18/2021] [Indexed: 01/12/2023] Open
Abstract
Down syndrome is the main cause of intellectual disabilities with a large set of comorbidities from developmental origins but also that appeared across life span. Investigation of the genetic overdosage found in Down syndrome, due to the trisomy of human chromosome 21, has pointed to one main driver gene, the Dual-specificity tyrosine-regulated kinase 1A (Dyrk1a). Dyrk1a is a murine homolog of the drosophila minibrain gene. It has been found to be involved in many biological processes during development and in adulthood. Further analysis showed its haploinsufficiency in mental retardation disease 7 and its involvement in Alzheimer's disease. DYRK1A plays a role in major developmental steps of brain development, controlling the proliferation of neural progenitors, the migration of neurons, their dendritogenesis and the function of the synapse. Several strategies targeting the overdosage of DYRK1A in DS with specific kinase inhibitors have showed promising evidence that DS cognitive conditions can be alleviated. Nevertheless, providing conditions for proper temporal treatment and to tackle the neurodevelopmental and the neurodegenerative aspects of DS across life span is still an open question.
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Affiliation(s)
- Helin Atas-Ozcan
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), 1 rue Laurent Fries, 67404 Illkirch Graffenstaden, France; (H.A.-O.); (V.B.); (A.D.)
| | - Véronique Brault
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), 1 rue Laurent Fries, 67404 Illkirch Graffenstaden, France; (H.A.-O.); (V.B.); (A.D.)
| | - Arnaud Duchon
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), 1 rue Laurent Fries, 67404 Illkirch Graffenstaden, France; (H.A.-O.); (V.B.); (A.D.)
| | - Yann Herault
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), 1 rue Laurent Fries, 67404 Illkirch Graffenstaden, France; (H.A.-O.); (V.B.); (A.D.)
- Université de Strasbourg, CNRS, INSERM, Celphedia, Phenomin-Institut Clinique de la Souris (ICS), 1 rue Laurent Fries, 67404 Illkirch Graffenstaden, France
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9
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Sánchez-Hidalgo AC, Arias-Aragón F, Romero-Barragán MT, Martín-Cuevas C, Delgado-García JM, Martinez-Mir A, Scholl FG. Selective expression of the neurexin substrate for presenilin in the adult forebrain causes deficits in associative memory and presynaptic plasticity. Exp Neurol 2021; 347:113896. [PMID: 34662541 DOI: 10.1016/j.expneurol.2021.113896] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 09/27/2021] [Accepted: 10/10/2021] [Indexed: 01/25/2023]
Abstract
Presenilins (PS) form the active subunit of the gamma-secretase complex, which mediates the proteolytic clearance of a broad variety of type-I plasma membrane proteins. Loss-of-function mutations in PSEN1/2 genes are the leading cause of familial Alzheimer's disease (fAD). However, the PS/gamma-secretase substrates relevant for the neuronal deficits associated with a loss of PS function are not completely known. The members of the neurexin (Nrxn) family of presynaptic plasma membrane proteins are candidates to mediate aspects of the synaptic and memory deficits associated with a loss of PS function. Previous work has shown that fAD-linked PS mutants or inactivation of PS by genetic and pharmacological approaches failed to clear Nrxn C-terminal fragments (NrxnCTF), leading to its abnormal accumulation at presynaptic terminals. Here, we generated transgenic mice that selectively recreate the presynaptic accumulation of NrxnCTF in adult forebrain neurons, leaving unaltered the function of PS/gamma-secretase complex towards other substrates. Behavioral characterization identified selective impairments in NrxnCTF mice, including decreased fear-conditioning memory. Electrophysiological recordings in medial prefrontal cortex-basolateral amygdala (mPFC-BLA) of behaving mice showed normal synaptic transmission and uncovered specific defects in synaptic facilitation. These data functionally link the accumulation of NrxnCTF with defects in associative memory and short-term synaptic plasticity, pointing at impaired clearance of NrxnCTF as a new mediator in AD.
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Affiliation(s)
- Ana C Sánchez-Hidalgo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avda. Manuel Siurot s/n, Sevilla 41013, Spain; Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Avda. Sánchez Pizjuán, 4, Sevilla 41009, Spain
| | - Francisco Arias-Aragón
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avda. Manuel Siurot s/n, Sevilla 41013, Spain; Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Avda. Sánchez Pizjuán, 4, Sevilla 41009, Spain
| | | | - Celia Martín-Cuevas
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avda. Manuel Siurot s/n, Sevilla 41013, Spain; Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Avda. Sánchez Pizjuán, 4, Sevilla 41009, Spain
| | | | - Amalia Martinez-Mir
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avda. Manuel Siurot s/n, Sevilla 41013, Spain
| | - Francisco G Scholl
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avda. Manuel Siurot s/n, Sevilla 41013, Spain; Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Avda. Sánchez Pizjuán, 4, Sevilla 41009, Spain.
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10
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Ledreux A, Thomas S, Hamlett ED, Trautman C, Gilmore A, Rickman Hager E, Paredes DA, Margittai M, Fortea J, Granholm AC. Small Neuron-Derived Extracellular Vesicles from Individuals with Down Syndrome Propagate Tau Pathology in the Wildtype Mouse Brain. J Clin Med 2021; 10:3931. [PMID: 34501378 PMCID: PMC8432237 DOI: 10.3390/jcm10173931] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 08/24/2021] [Accepted: 08/28/2021] [Indexed: 12/11/2022] Open
Abstract
Individuals with Down syndrome (DS) exhibit Alzheimer's disease (AD) pathology at a young age, including amyloid plaques and neurofibrillary tangles (NFTs). Tau pathology can spread via extracellular vesicles, such as exosomes. The cargo of neuron-derived small extracellular vesicles (NDEVs) from individuals with DS contains p-Tau at an early age. The goal of the study was to investigate whether NDEVs isolated from the blood of individuals with DS can spread Tau pathology in the brain of wildtype mice. We purified NDEVs from the plasma of patients with DS-AD and controls and injected small quantities using stereotaxic surgery into the dorsal hippocampus of adult wildtype mice. Seeding competent Tau conformers were amplified in vitro from DS-AD NDEVs but not NDEVs from controls. One month or 4 months post-injection, we examined Tau pathology in mouse brains. We found abundant p-Tau immunostaining in the hippocampus of the mice injected with DS-AD NDEVs compared to injections of age-matched control NDEVs. Double labeling with neuronal and glial markers showed that p-Tau staining was largely found in neurons and, to a lesser extent, in glial cells and that p-Tau immunostaining was spreading along the corpus callosum and the medio-lateral axis of the hippocampus. These studies demonstrate that NDEVs from DS-AD patients exhibit Tau seeding capacity and give rise to tangle-like intracellular inclusions.
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Affiliation(s)
- Aurélie Ledreux
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
| | - Sarah Thomas
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
| | - Eric D. Hamlett
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC 29425, USA;
| | - Camille Trautman
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
| | - Anah Gilmore
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
| | - Emily Rickman Hager
- Department of Chemistry and Biochemistry, University of Denver, Denver, CO 80208, USA; (E.R.H.); (M.M.)
| | - Daniel A. Paredes
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
| | - Martin Margittai
- Department of Chemistry and Biochemistry, University of Denver, Denver, CO 80208, USA; (E.R.H.); (M.M.)
| | - Juan Fortea
- Hospital de la Santa Creu i Sant Pau and Catalan Down Syndrome Foundation, 08041 Barcelona, Spain;
| | - Ann-Charlotte Granholm
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
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11
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Ge Q, Hu X, Ma N, Sun M, Zhang L, Cai Z, Tan R, Lu H. Maternal high-salt diet during pregnancy impairs synaptic plasticity and memory in offspring. FASEB J 2021; 35:e21244. [PMID: 33715195 DOI: 10.1096/fj.202001890r] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 11/11/2022]
Abstract
Excess salt intake harms the brain health and cognitive functions, but whether a maternal high-salt diet (HSD) affects the brain development and neural plasticity of offspring remains unclear. Here, using a range of behavioral tests, we reported that the offspring of maternal HSD subjects exhibited short- and long-term memory deficits, especially in spatial memory in adulthood. Moreover, impairments in synaptic transmission and plasticity in the hippocampus were observed in adult offspring by using in vivo electrophysiology. Consistently, the number of astrocytes but not neurons in the hippocampus of the offspring from the HSD group were significantly decreased, and ERK and AKT signaling pathways involved in neurodevelopment were highly activated only during juvenile. In addition, the expression of synaptic proteins decreased both in juvenile and adulthood, and this effect might be involved in synaptic dysfunction. Collectively, these data demonstrated that the maternal HSD might cause adult offspring synaptic dysfunction and memory loss. It is possibly due to the reduction of astrocytes in juvenile.
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Affiliation(s)
- Qian Ge
- Department of Neurobiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China
| | - Xiaoxuan Hu
- Department of Neurobiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China.,Department of Human Anatomy and Histo-embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China
| | - Ning Ma
- Department of Neurobiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China.,Department of Human Anatomy and Histo-embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China
| | - Meiqi Sun
- Department of Neurobiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China
| | - Liyun Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China.,Department of Human Anatomy and Histo-embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China
| | - Zhenlu Cai
- Department of Neurobiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China
| | - Ruolan Tan
- Department of Neurobiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China.,Department of Human Anatomy and Histo-embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China
| | - Haixia Lu
- Department of Neurobiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China
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12
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Urbano-Gámez JD, Casañas JJ, Benito I, Montesinos ML. Prenatal treatment with rapamycin restores enhanced hippocampal mGluR-LTD and mushroom spine size in a Down's syndrome mouse model. Mol Brain 2021; 14:84. [PMID: 34034796 PMCID: PMC8152312 DOI: 10.1186/s13041-021-00795-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 05/18/2021] [Indexed: 11/10/2022] Open
Abstract
Down syndrome (DS) is the most frequent genetic cause of intellectual disability including hippocampal-dependent memory deficits. We have previously reported hippocampal mTOR (mammalian target of rapamycin) hyperactivation, and related plasticity as well as memory deficits in Ts1Cje mice, a DS experimental model. Here we characterize the proteome of hippocampal synaptoneurosomes (SNs) from these mice, and found a predicted alteration of synaptic plasticity pathways, including long term depression (LTD). Accordingly, mGluR-LTD (metabotropic Glutamate Receptor-LTD) is enhanced in the hippocampus of Ts1Cje mice and this is correlated with an increased proportion of a particular category of mushroom spines in hippocampal pyramidal neurons. Remarkably, prenatal treatment of these mice with rapamycin has a positive pharmacological effect on both phenotypes, supporting the therapeutic potential of rapamycin/rapalogs for DS intellectual disability.
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Affiliation(s)
- Jesús David Urbano-Gámez
- Departamento de Fisiología Médica Y Biofísica, Universidad de Sevilla, Av. Sánchez-Pizjuán 4, 41009, Sevilla, Spain.,Instituto de Biomedicina de Sevilla, IBIS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain
| | - Juan José Casañas
- Departamento de Fisiología Médica Y Biofísica, Universidad de Sevilla, Av. Sánchez-Pizjuán 4, 41009, Sevilla, Spain.,Instituto de Biomedicina de Sevilla, IBIS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain
| | - Itziar Benito
- Departamento de Fisiología Médica Y Biofísica, Universidad de Sevilla, Av. Sánchez-Pizjuán 4, 41009, Sevilla, Spain.,Instituto de Biomedicina de Sevilla, IBIS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain.,Servicio de Animalario, Hospital Universitario Virgen Macarena (HUVM), 41009, Sevilla, Spain
| | - María Luz Montesinos
- Departamento de Fisiología Médica Y Biofísica, Universidad de Sevilla, Av. Sánchez-Pizjuán 4, 41009, Sevilla, Spain. .,Instituto de Biomedicina de Sevilla, IBIS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain.
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13
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Lanzillotta C, Di Domenico F. Stress Responses in Down Syndrome Neurodegeneration: State of the Art and Therapeutic Molecules. Biomolecules 2021; 11:biom11020266. [PMID: 33670211 PMCID: PMC7916967 DOI: 10.3390/biom11020266] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 02/05/2021] [Accepted: 02/09/2021] [Indexed: 12/11/2022] Open
Abstract
Down syndrome (DS) is the most common genomic disorder characterized by the increased incidence of developing early Alzheimer’s disease (AD). In DS, the triplication of genes on chromosome 21 is intimately associated with the increase of AD pathological hallmarks and with the development of brain redox imbalance and aberrant proteostasis. Increasing evidence has recently shown that oxidative stress (OS), associated with mitochondrial dysfunction and with the failure of antioxidant responses (e.g., SOD1 and Nrf2), is an early signature of DS, promoting protein oxidation and the formation of toxic protein aggregates. In turn, systems involved in the surveillance of protein synthesis/folding/degradation mechanisms, such as the integrated stress response (ISR), the unfolded stress response (UPR), and autophagy, are impaired in DS, thus exacerbating brain damage. A number of pre-clinical and clinical studies have been applied to the context of DS with the aim of rescuing redox balance and proteostasis by boosting the antioxidant response and/or inducing the mechanisms of protein re-folding and clearance, and at final of reducing cognitive decline. So far, such therapeutic approaches demonstrated their efficacy in reverting several aspects of DS phenotype in murine models, however, additional studies aimed to translate these approaches in clinical practice are still needed.
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14
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Martínez-Cué C, Rueda N. Signalling Pathways Implicated in Alzheimer's Disease Neurodegeneration in Individuals with and without Down Syndrome. Int J Mol Sci 2020; 21:E6906. [PMID: 32962300 PMCID: PMC7555886 DOI: 10.3390/ijms21186906] [Citation(s) in RCA: 10] [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: 08/31/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 02/07/2023] Open
Abstract
Down syndrome (DS), the most common cause of intellectual disability of genetic origin, is characterized by alterations in central nervous system morphology and function that appear from early prenatal stages. However, by the fourth decade of life, all individuals with DS develop neuropathology identical to that found in sporadic Alzheimer's disease (AD), including the development of amyloid plaques and neurofibrillary tangles due to hyperphosphorylation of tau protein, loss of neurons and synapses, reduced neurogenesis, enhanced oxidative stress, and mitochondrial dysfunction and neuroinflammation. It has been proposed that DS could be a useful model for studying the etiopathology of AD and to search for therapeutic targets. There is increasing evidence that the neuropathological events associated with AD are interrelated and that many of them not only are implicated in the onset of this pathology but are also a consequence of other alterations. Thus, a feedback mechanism exists between them. In this review, we summarize the signalling pathways implicated in each of the main neuropathological aspects of AD in individuals with and without DS as well as the interrelation of these pathways.
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Affiliation(s)
- Carmen Martínez-Cué
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, 39011 Santander, Spain;
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15
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Lee JY, Kennedy BK, Liao CY. Mechanistic target of rapamycin signaling in mouse models of accelerated aging. J Gerontol A Biol Sci Med Sci 2020; 75:64-72. [PMID: 30900725 DOI: 10.1093/gerona/glz059] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 02/23/2019] [Indexed: 01/06/2023] Open
Abstract
The mechanistic target of rapamycin (mTOR) is an essential nutrient-sensing kinase that integrates and regulates a number of fundamental cellular processes required for cell growth, cell motility, translation, metabolism, and autophagy. mTOR signaling has been implicated in the progression of many human diseases, and its dysregulation has been reported in several pathological processes, especially in age-related human diseases and mouse models of accelerated aging. In addition, many studies have demonstrated that the regulation of mTOR activity has a beneficial effect on longevity in several mouse models of aging. However, not all mouse models of accelerated aging show positive effects on aging-associated phenotypes in response to targeting mTOR signaling. Here, we review the effects of interventions that modulate mTOR signaling on aging-related phenotypes in different mouse models of accelerated aging and discuss their implications with respect to aging and aging-related disorders.
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Affiliation(s)
- Jin Young Lee
- Buck Institute for Research on Aging, Novato, California
| | - Brian K Kennedy
- Buck Institute for Research on Aging, Novato, California
- Department of Biochemistry and Physiology, National University of Singapore, Singapore
- Centre for Healthy Ageing, National University Health System, Singapore
- Singapore Institute for Clinical Sciences, A*STAR, Singapore
| | - Chen-Yu Liao
- Buck Institute for Research on Aging, Novato, California
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16
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Wang K, Sun W, Zhang L, Guo W, Xu J, Liu S, Zhou Z, Zhang Y. Oleanolic Acid Ameliorates Aβ25-35 Injection-induced Memory Deficit in Alzheimer's Disease Model Rats by Maintaining Synaptic Plasticity. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2019; 17:389-399. [PMID: 29793416 PMCID: PMC6327117 DOI: 10.2174/1871527317666180525113109] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 05/07/2018] [Accepted: 05/22/2018] [Indexed: 12/13/2022]
Abstract
Background: Abnormal amyloid β (Aβ) accumulation and deposition in the hippocampus is an essential process in Alzheimer’s disease (AD). Objective: To investigate whether Oleanolic acid (OA) could improve memory deficit in AD model and its possible mechanism. Methods: Forty-five SD rats were randomly divided into sham operation group, model group, and OA group. AD models by injection of Aβ25-35 were built. Morris water maze (MWM) was applied to inves-tigate learning and memory, transmission electron microscope (TEM) to observe the ultrastructure of synapse, western blot to the proteins, electrophysiology for long-term potentiation (LTP), and Ca2+ con-centration in synapse was also measured. Results: The latency time in model group was significantly longer than that in sham operation group (P=0.0001); while it was significantly shorter in the OA group than that in model group (P=0.0001); compared with model group, the times of cross-platform in OA group significantly increased (P=0.0001). TEM results showed OA could alleviate neuron damage and synapses changes induced by Aβ25-35. The expressions of CaMKII, PKC, NMDAR2B, BDNF, TrkB, and CREB protein were signif-icantly improved by OA (P=0.0001, 0.036, 0.041, 0.0001, 0.0001, 0.026, respectively) compared with that in model group; the concentration of Ca2+ was significantly lower in OA group (1.11±0.42) than that in model group (1.68±0.18); and the slope rate (P=0.0001) and amplitude (P=0.0001) of f-EPSP significantly increased in OA group. Conclusion: The present results support that OA could ameliorate Aβ-induced memory loss of AD rats by maintaining synaptic plasticity of the hippocampus
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Affiliation(s)
- Kai Wang
- Graduate Institutes, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China
| | - Weiming Sun
- Graduate Institutes, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China
| | - Linlin Zhang
- Department of Neurology, the Second Hospital Affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, 300150, China
| | - Wei Guo
- Department of Neurology, the Second Hospital Affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, 300150, China
| | - Jiachun Xu
- Graduate Institutes, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China
| | - Shuang Liu
- Department of Neurology, the Second Hospital Affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, 300150, China
| | - Zhen Zhou
- Department of Neurology, the Second Hospital Affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, 300150, China
| | - Yulian Zhang
- Department of Neurology, the Second Hospital Affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, 300150, China
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17
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Di Domenico F, Tramutola A, Barone E, Lanzillotta C, Defever O, Arena A, Zuliani I, Foppoli C, Iavarone F, Vincenzoni F, Castagnola M, Butterfield DA, Perluigi M. Restoration of aberrant mTOR signaling by intranasal rapamycin reduces oxidative damage: Focus on HNE-modified proteins in a mouse model of down syndrome. Redox Biol 2019; 23:101162. [PMID: 30876754 PMCID: PMC6859577 DOI: 10.1016/j.redox.2019.101162] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 02/26/2019] [Accepted: 03/05/2019] [Indexed: 01/05/2023] Open
Abstract
Increasing evidences support the notion that the impairment of intracellular degradative machinery is responsible for the accumulation of oxidized/misfolded proteins that ultimately results in the deposition of protein aggregates. These events are key pathological aspects of "protein misfolding diseases", including Alzheimer disease (AD). Interestingly, Down syndrome (DS) neuropathology shares many features with AD, such as the deposition of both amyloid plaques and neurofibrillary tangles. Studies from our group and others demonstrated, in DS brain, the dysfunction of both proteasome and autophagy degradative systems, coupled with increased oxidative damage. Further, we observed the aberrant increase of mTOR signaling and of its down-stream pathways in both DS brain and in Ts65Dn mice. Based on these findings, we support the ability of intranasal rapamycin treatment (InRapa) to restore mTOR pathway but also to restrain oxidative stress resulting in the decreased accumulation of lipoxidized proteins. By proteomics approach, we were able to identify specific proteins that showed decreased levels of HNE-modification after InRapa treatment compared with vehicle group. Among MS-identified proteins, we found that reduced oxidation of arginase-1 (ARG-1) and protein phosphatase 2A (PP2A) might play a key role in reducing brain damage associated with synaptic transmission failure and tau hyperphosphorylation. InRapa treatment, by reducing ARG-1 protein-bound HNE levels, rescues its enzyme activity and conceivably contribute to the recovery of arginase-regulated functions. Further, it was shown that PP2A inhibition induces tau hyperphosphorylation and spatial memory deficits. Our data suggest that InRapa was able to rescue PP2A activity as suggested by reduced p-tau levels. In summary, considering that mTOR pathway is a central hub of multiple intracellular signaling, we propose that InRapa treatment is able to lower the lipoxidation-mediated damage to proteins, thus representing a valuable therapeutic strategy to reduce the early development of AD pathology in DS population.
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Affiliation(s)
- Fabio Di Domenico
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Antonella Tramutola
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Eugenio Barone
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy; Universidad Autònoma de Chile, Instituto de Ciencias Biomédicas, Facultad de alud, Providencia, Santiago, Chile
| | - Chiara Lanzillotta
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Olivia Defever
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Andrea Arena
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Ilaria Zuliani
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Cesira Foppoli
- CNR Institute of Molecular Biology and Pathology, Sapienza University of Rome, Rome, Italy
| | - Federica Iavarone
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Rome, Italy; Fondazione Policlinico Universitario A. Gemelli, IRCCS, Rome, Italy
| | - Federica Vincenzoni
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Rome, Italy; Fondazione Policlinico Universitario A. Gemelli, IRCCS, Rome, Italy
| | - Massimo Castagnola
- Laboratorio di Proteomica e Metabonomica, IRCCS, Fondazione Santa Lucia - Rome and Istituto per la Chimica del Riconoscimento Molecolare, CNR, Rome, Italy
| | - D Allan Butterfield
- Department of Chemistry and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Marzia Perluigi
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy.
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18
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Tramutola A, Lanzillotta C, Barone E, Arena A, Zuliani I, Mosca L, Blarzino C, Butterfield DA, Perluigi M, Di Domenico F. Intranasal rapamycin ameliorates Alzheimer-like cognitive decline in a mouse model of Down syndrome. Transl Neurodegener 2018; 7:28. [PMID: 30410750 PMCID: PMC6218962 DOI: 10.1186/s40035-018-0133-9] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 10/11/2018] [Indexed: 02/08/2023] Open
Abstract
Background Down syndrome (DS) individuals, by the age of 40s, are at increased risk to develop Alzheimer-like dementia, with deposition in brain of senile plaques and neurofibrillary tangles. Our laboratory recently demonstrated the disturbance of PI3K/AKT/mTOR axis in DS brain, prior and after the development of Alzheimer Disease (AD). The aberrant modulation of the mTOR signalling in DS and AD age-related cognitive decline affects crucial neuronal pathways, including insulin signaling and autophagy, involved in pathology onset and progression. Within this context, the therapeutic use of mTOR-inhibitors may prevent/attenuate the neurodegenerative phenomena. By our work we aimed to rescue mTOR signalling in DS mice by a novel rapamycin intranasal administration protocol (InRapa) that maximizes brain delivery and reduce systemic side effects. Methods Ts65Dn mice were administered with InRapa for 12 weeks, starting at 6 months of age demonstrating, at the end of the treatment by radial arms maze and novel object recognition testing, rescued cognition. Results The analysis of mTOR signalling, after InRapa, demonstrated in Ts65Dn mice hippocampus the inhibition of mTOR (reduced to physiological levels), which led, through the rescue of autophagy and insulin signalling, to reduced APP levels, APP processing and APP metabolites production, as well as, to reduced tau hyperphosphorylation. In addition, a reduction of oxidative stress markers was also observed. Discussion These findings demonstrate that chronic InRapa administration is able to exert a neuroprotective effect on Ts65Dn hippocampus by reducing AD pathological hallmarks and by restoring protein homeostasis, thus ultimately resulting in improved cognition. Results are discussed in term of a potential novel targeted therapeutic approach to reduce cognitive decline and AD-like neuropathology in DS individuals.
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Affiliation(s)
- Antonella Tramutola
- 1Department of Biochemical Sciences, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Chiara Lanzillotta
- 1Department of Biochemical Sciences, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Eugenio Barone
- 1Department of Biochemical Sciences, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy.,2Universidad Autònoma de Chile, Instituto de Ciencias Biomédicas, Facultad de alud, Avenida Pedro de Valdivia 425, Providencia, Santiago, Chile
| | - Andrea Arena
- 1Department of Biochemical Sciences, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Ilaria Zuliani
- 1Department of Biochemical Sciences, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Luciana Mosca
- 1Department of Biochemical Sciences, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Carla Blarzino
- 1Department of Biochemical Sciences, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | - D Allan Butterfield
- 3Department of Chemistry and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40506-0055 USA
| | - Marzia Perluigi
- 1Department of Biochemical Sciences, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Fabio Di Domenico
- 1Department of Biochemical Sciences, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
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Cassano T, Magini A, Giovagnoli S, Polchi A, Calcagnini S, Pace L, Lavecchia MA, Scuderi C, Bronzuoli MR, Ruggeri L, Gentileschi MP, Romano A, Gaetani S, De Marco F, Emiliani C, Dolcetta D. Early intrathecal infusion of everolimus restores cognitive function and mood in a murine model of Alzheimer's disease. Exp Neurol 2018; 311:88-105. [PMID: 30243986 DOI: 10.1016/j.expneurol.2018.09.011] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 08/13/2018] [Accepted: 09/17/2018] [Indexed: 01/05/2023]
Abstract
The discovery that mammalian target of rapamycin (mTOR) inhibition increases lifespan in mice and restores/delays many aging phenotypes has led to the identification of a novel potential therapeutic target for the treatment of Alzheimer's disease (AD). Among mTOR inhibitors, everolimus, which has been developed to improve the pharmacokinetic characteristics of rapamycin, has been extensively profiled in preclinical and clinical studies as anticancer and immunosuppressive agent, but no information is available about its potential effects on neurodegenerative disorders. Using a reliable mouse model of AD (3 × Tg-AD mice), we explored whether short-term treatment with everolimus injected directly into the brain by osmotic pumps was able to modify AD-like pathology with low impact on peripheral organs. We first established in non-transgenic mice the stability of everolimus at 37 °C in comparison with rapamycin and, then, evaluated its pharmacokinetics and pharmacodynamics profiles through either a single peripheral (i.p.) or central (i.c.v.) route of administration. Finally, 6-month-old (symptomatic phase) 3 × Tg-AD mice were treated with continuous infusion of either vehicle or everolimus (0.167 μg/μl/day, i.c.v.) using the osmotic pumps. Four weeks after the beginning of infusion, we tested our hypothesis following an integrated approach, including behavioral (tests for cognitive and depressive-like alterations), biochemical and immunohistochemical analyses. Everolimus (i) showed higher stability than rapamycin at 37 °C, (ii) poorly crossed the blood-brain barrier after i.p. injection, (iii) was slowly metabolized in the brain due to a longer t1/2 in the brain compared to blood, and (iv) was more effective in the CNS when administered centrally compared to a peripheral route. Moreover, the everolimus-induced mTOR inhibition reduced human APP/Aβ and human tau levels and improved cognitive function and depressive-like phenotype in the 3 × Tg-AD mice. The intrathecal infusion of everolimus may be effective to treat early stages of AD-pathology through a short and cyclic administration regimen, with short-term outcomes and a low impact on peripheral organs.
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Affiliation(s)
- Tommaso Cassano
- Department of Clinical and Experimental Medicine, Medical School, University of Foggia, 71100 Foggia, Italy.
| | - Alessandro Magini
- Department of Chemistry, Biology and Biotechnology, University of Perugia, 06126 Perugia, Italy
| | - Stefano Giovagnoli
- Department of Pharmaceutical Sciences, University of Perugia, 06123 Perugia, Italy
| | - Alice Polchi
- Department of Chemistry, Biology and Biotechnology, University of Perugia, 06126 Perugia, Italy
| | - Silvio Calcagnini
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, 00185 Rome, Italy
| | - Lorenzo Pace
- Department of Clinical and Experimental Medicine, Medical School, University of Foggia, 71100 Foggia, Italy
| | - Michele Angelo Lavecchia
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, 00185 Rome, Italy
| | - Caterina Scuderi
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, 00185 Rome, Italy
| | - Maria Rosanna Bronzuoli
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, 00185 Rome, Italy
| | - Loredana Ruggeri
- Division of Hematology and Clinical Immunology and Bone Marrow Transplant Program, Department of Medicine, University of Perugia, 06132 Perugia, Italy
| | - Maria Pia Gentileschi
- UOSD SAFU, RiDAIT Dept, The Regina Elena National Cancer Institute, 00144 Rome, Italy
| | - Adele Romano
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, 00185 Rome, Italy
| | - Silvana Gaetani
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, 00185 Rome, Italy
| | - Federico De Marco
- UOSD SAFU, RiDAIT Dept, The Regina Elena National Cancer Institute, 00144 Rome, Italy
| | - Carla Emiliani
- Department of Chemistry, Biology and Biotechnology, University of Perugia, 06126 Perugia, Italy
| | - Diego Dolcetta
- UOSD SAFU, RiDAIT Dept, The Regina Elena National Cancer Institute, 00144 Rome, Italy.
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20
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Kaur G, Gauthier SA, Perez-Gonzalez R, Pawlik M, Singh AB, Cosby B, Mohan PS, Smiley JF, Levy E. Cystatin C prevents neuronal loss and behavioral deficits via the endosomal pathway in a mouse model of down syndrome. Neurobiol Dis 2018; 120:165-173. [PMID: 30176349 DOI: 10.1016/j.nbd.2018.08.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 08/14/2018] [Accepted: 08/30/2018] [Indexed: 01/18/2023] Open
Abstract
Cystatin C (CysC) plays diverse protective roles under conditions of neuronal challenge. We investigated whether CysC protects from trisomy-induced pathologies in a mouse model of Down syndrome (DS), the most common cause of developmental cognitive and behavioral impairments in humans. We have previously shown that the segmental trisomy mouse model, Ts[Rb(12.1716)]2Cje (Ts2) has DS-like neuronal and behavioral deficiencies. The current study reveals that transgene-mediated low levels of human CysC overexpression has a preventive effect on numerous neuropathologies in the brains of Ts2 mice, including reducing early and late endosome enlargement in cortical neurons and decreasing loss of basal forebrain cholinergic neurons (BFCNs). Consistent with these cellular benefits, behavioral dysfunctions were also prevented, including deficits in nesting behavior and spatial memory. We determined that the CysC-induced neuroprotective mechanism involves activation of the phosphotidylinositol kinase (PI3K)/AKT pathway. Activating this pathway leads to enhanced clearance of accumulated endosomal substrates, protecting cells from DS-mediated dysfunctions in the endosomal system and, for BFCNs, from neurodegeneration. Our findings suggest that modulation of the PI3/AKT pathway offers novel therapeutic interventions for patients with DS.
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Affiliation(s)
| | | | | | - Monika Pawlik
- Nathan S. Kline Institute, Orangeburg, NY, USA 10962
| | | | | | | | - John F Smiley
- Nathan S. Kline Institute, Orangeburg, NY, USA 10962; Department of Psychiatry, NYU Langone School of Medicine, New York, NY, USA 10016
| | - Efrat Levy
- Nathan S. Kline Institute, Orangeburg, NY, USA 10962; Department of Psychiatry, NYU Langone School of Medicine, New York, NY, USA 10016; Department of Biochemistry and Molecular Pharmacology, NYU Langone School of Medicine, New York, NY, USA 10016; Neuroscience Institute, NYU Langone School of Medicine, New York, NY, USA 10016.
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21
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Herault Y, Delabar JM, Fisher EMC, Tybulewicz VLJ, Yu E, Brault V. Rodent models in Down syndrome research: impact and future opportunities. Dis Model Mech 2018; 10:1165-1186. [PMID: 28993310 PMCID: PMC5665454 DOI: 10.1242/dmm.029728] [Citation(s) in RCA: 120] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Down syndrome is caused by trisomy of chromosome 21. To date, a multiplicity of mouse models with Down-syndrome-related features has been developed to understand this complex human chromosomal disorder. These mouse models have been important for determining genotype-phenotype relationships and identification of dosage-sensitive genes involved in the pathophysiology of the condition, and in exploring the impact of the additional chromosome on the whole genome. Mouse models of Down syndrome have also been used to test therapeutic strategies. Here, we provide an overview of research in the last 15 years dedicated to the development and application of rodent models for Down syndrome. We also speculate on possible and probable future directions of research in this fast-moving field. As our understanding of the syndrome improves and genome engineering technologies evolve, it is necessary to coordinate efforts to make all Down syndrome models available to the community, to test therapeutics in models that replicate the whole trisomy and design new animal models to promote further discovery of potential therapeutic targets. Summary: Mouse models have boosted therapeutic options for Down syndrome, and improved models are being developed to better understand the pathophysiology of this genetic condition.
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Affiliation(s)
- Yann Herault
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, 1 rue Laurent Fries, 67404 Illkirch, France .,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France.,Université de Strasbourg, 67404 Illkirch, France.,T21 Research Society, Brain and Spine Institute (ICM), 75013 Paris
| | - Jean M Delabar
- T21 Research Society, Brain and Spine Institute (ICM), 75013 Paris.,Université Paris Diderot, Sorbonne Paris Cité, Unité de Biologie Fonctionnelle et Adaptative, UMR8251, CNRS, 75205 Paris, France.,INSERM U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et la Moelle épinière, ICM, 75013 Paris, France.,Brain and Spine Institute (ICM) CNRS UMR7225, INSERM UMRS 975, 75013 Paris, France
| | - Elizabeth M C Fisher
- T21 Research Society, Brain and Spine Institute (ICM), 75013 Paris.,Department of Neurodegenerative Disease, Institute of Neurology, University College London, London, WC1N 3BG, UK.,LonDownS Consortium, London, W1T 7NF UK
| | - Victor L J Tybulewicz
- T21 Research Society, Brain and Spine Institute (ICM), 75013 Paris.,LonDownS Consortium, London, W1T 7NF UK.,The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.,Department of Medicine, Imperial College, London, SW7 2AZ, UK
| | - Eugene Yu
- T21 Research Society, Brain and Spine Institute (ICM), 75013 Paris.,The Children's Guild Foundation Down Syndrome Research Program, Department of Cancer Genetics and Genetics Program, Roswell Park Cancer Institute, Buffalo, NY 14263, USA.,Department of Cellular and Molecular Biology, Roswell Park Division of Graduate School, Genetics, Genomics and Bioinformatics Program, State University of New York at Buffalo, Buffalo, NY 14263, USA
| | - Veronique Brault
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, 1 rue Laurent Fries, 67404 Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France.,Université de Strasbourg, 67404 Illkirch, France
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22
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Facilitation of hippocampal long-term potentiation and reactivation of latent HIV-1 via AMPK activation: Common mechanism of action linking learning, memory, and the potential eradication of HIV-1. Med Hypotheses 2018; 116:61-73. [DOI: 10.1016/j.mehy.2018.04.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Revised: 10/27/2017] [Accepted: 04/20/2018] [Indexed: 12/31/2022]
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23
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Masini D, Bonito-Oliva A, Bertho M, Fisone G. Inhibition of mTORC1 Signaling Reverts Cognitive and Affective Deficits in a Mouse Model of Parkinson's Disease. Front Neurol 2018; 9:208. [PMID: 29686643 PMCID: PMC5900003 DOI: 10.3389/fneur.2018.00208] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 03/16/2018] [Indexed: 01/14/2023] Open
Abstract
Non-motor symptoms, including cognitive deficits and affective disorders, are frequently diagnosed in Parkinson’s disease (PD) patients and are only partially alleviated by dopamine replacement therapy. Here, we used a 6-hydroxydopamine (6-OHDA) mouse model of PD to examine the effects exerted on non-motor symptoms by inhibition of the mammalian target of rapamycin complex 1 (mTORC1), which is involved in the control of protein synthesis, cell growth, and metabolism. We show that rapamycin, which acts as an allosteric inhibitor of mTORC1, counteracts the impairment of novel object recognition. A similar effect is produced by PF-4708671, an inhibitor of the downstream target of mTORC1, ribosomal protein S6 kinase (S6K). Rapamycin is also able to reduce depression-like behavior in PD mice, as indicated by decreased immobility in the forced swim test. Moreover, rapamycin exerts anxiolytic effects, thereby reducing thigmotaxis in the open field and increasing exploration of the open arm in the elevated plus maze. In contrast to rapamycin, administration of PF-4708671 to PD mice does not counteract depression- and anxiety-like behaviors. Altogether, these results identify mTORC1 as a target for the development of drugs that, in combination with standard antiparkinsonian agents, may widen the efficacy of current therapies for the cognitive and affective symptoms of PD.
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Affiliation(s)
- Débora Masini
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | | | - Maëlle Bertho
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Gilberto Fisone
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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24
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The p75 neurotrophin receptor might mediate sepsis-induced synaptic and cognitive impairments. Behav Brain Res 2018; 347:339-349. [PMID: 29604364 DOI: 10.1016/j.bbr.2018.03.042] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 03/27/2018] [Accepted: 03/27/2018] [Indexed: 12/16/2022]
Abstract
Systemic inflammation induces cognitive impairment, yet the mechanism involved in this process is unclear. Neurotrophin receptor p75 (p75NTR) signaling is a key pathological factor contributing to neurobehavioral abnormalities in many neurodegenerative diseases. However, the role of p75NTR signaling in the regulation of sepsis-induced cognitive impairment remains largely to be elucidated. In this study, systemic inflammation was induced by cecal ligation and puncture (CLP). Neurobehavioral performances were evaluated by open field, novel object recognition, and fear conditioning tests. The expressions of proinflammatory cytokines (tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), IL-6, IL-10), apoptosis marker cleaved caspase-3, ionized calcium binding adaptor molecule 1 (IBA1), proBDNF, p75NTR, c-Jun N-terminal kinase (JNK), and pJNK in the hippocampus were determined by enzyme-linked immunosorbent assay, western blot analysis, and immunofluorescence. The synaptic marker in the CA1 region of the hippocampus was assessed by Golgi staining. In the present study, we showed that systemic inflammation induced cognitive impairment, which was accompanied by increased expressions of hippocampcal proBDNF and p75NTR. Of note, we found that LM11A-31, an orally available, blood-brain barrier-permeant small-molecule p75NTR signaling modulator significantly reversed the sepsis-induced cognitive impairment and restored most of the abnormal biochemical parameters. Taken together, our study suggests that proBDNF/p75NTR signaling pathway might play a key role in the development of sepsis-induced cognitive impairment, whereas specific p75NTR inhibitor may provide a novel therapeutic approach for this disorder and possible other neurodegenerative diseases.
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25
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From altered synaptic plasticity to atypical learning: A computational model of Down syndrome. Cognition 2018; 171:15-24. [DOI: 10.1016/j.cognition.2017.10.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 10/23/2017] [Accepted: 10/25/2017] [Indexed: 01/09/2023]
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26
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Lowe SA, Hodge JJL, Usowicz MM. A third copy of the Down syndrome cell adhesion molecule (Dscam) causes synaptic and locomotor dysfunction in Drosophila. Neurobiol Dis 2017; 110:93-101. [PMID: 29196216 PMCID: PMC5773243 DOI: 10.1016/j.nbd.2017.11.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 10/13/2017] [Accepted: 11/27/2017] [Indexed: 02/06/2023] Open
Abstract
Down syndrome (DS) is caused by triplication of chromosome 21 (HSA21). It is characterised by intellectual disability and impaired motor coordination that arise from changes in brain volume, structure and function. However, the contribution of each HSA21 gene to these various phenotypes and to the causal alterations in neuronal and synaptic structure and function are largely unknown. Here we have investigated the effect of overexpression of the HSA21 gene DSCAM (Down syndrome cell adhesion molecule), on glutamatergic synaptic transmission and motor coordination, using Drosophila expressing three copies of Dscam1. Electrophysiological recordings of miniature and evoked excitatory junction potentials at the glutamatergic neuromuscular junction of Drosophila larvae showed that the extra copy of Dscam1 changed the properties of spontaneous and electrically-evoked transmitter release and strengthened short-term synaptic depression during high-frequency firing of the motor nerve. Behavioural analyses uncovered impaired locomotor coordination despite preserved gross motor function. This work identifies DSCAM as a candidate causative gene in DS that is sufficient to modify synaptic transmission and synaptic plasticity and cause a DS behavioural phenotype. Drosophila expressing a third copy of Dscam have altered neuromuscular transmission. Drosophila expressing a third copy of Dscam have deficits in locomotor coordination. Drosophila are a powerful system for studying single-gene effects in Down syndrome.
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Affiliation(s)
- Simon A Lowe
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, University Walk, Bristol BS8 1TD, UK
| | - James J L Hodge
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, University Walk, Bristol BS8 1TD, UK.
| | - Maria M Usowicz
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, University Walk, Bristol BS8 1TD, UK.
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27
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Montesinos ML. Local translation of the Down syndrome cell adhesion molecule (DSCAM) mRNA in the vertebrate central nervous system. J Neurogenet 2017; 31:223-230. [PMID: 29078722 DOI: 10.1080/01677063.2017.1391250] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- María Luz Montesinos
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Sevilla, Spain
- Instituto de Biomedicina de Sevilla, IBIS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain
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28
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Roesler R. Molecular mechanisms controlling protein synthesis in memory reconsolidation. Neurobiol Learn Mem 2017; 142:30-40. [DOI: 10.1016/j.nlm.2017.04.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 04/27/2017] [Accepted: 04/28/2017] [Indexed: 10/19/2022]
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29
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Sun J, Liu Y, Tran J, O'Neal P, Baudry M, Bi X. mTORC1-S6K1 inhibition or mTORC2 activation improves hippocampal synaptic plasticity and learning in Angelman syndrome mice. Cell Mol Life Sci 2016; 73:4303-4314. [PMID: 27173058 PMCID: PMC5056144 DOI: 10.1007/s00018-016-2269-z] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/27/2016] [Accepted: 05/06/2016] [Indexed: 02/07/2023]
Abstract
Emerging evidence is implicating abnormal activation of the mechanistic target of rapamycin (mTOR) pathway in several monogenetic neuropsychiatric disorders, including Angelman syndrome (AS), which is caused by deficiency in maternally inherited UBE3A. Using an AS mouse model, we show that semi-chronic rapamycin treatment improves long-term potentiation (LTP) and actin polymerization in hippocampal slices, spine morphology, and fear-conditioning learning. Activity of mTORC1 and of its downstream substrate, S6K1, was increased in hippocampus of AS mice. However, mTORC2 activity, as reflected by PKCα levels, was decreased. Both increased mTORC1 and decreased mTORC2 activities were reversed by semi-chronic rapamycin treatment. Acute treatment of hippocampal slices from AS mice with rapamycin or an S6K1 inhibitor, PF4708671, improved LTP, restored actin polymerization, and normalized mTORC1 and mTORC2 activity. These treatments also reduced Arc levels in AS mice. Treatment with Torin 1, an inhibitor of both mTORC1 and mTORC2, partially rescued LTP and actin polymerization in hippocampal slices from AS mice, while partially impairing them in wild-type (WT) mice. Torin 1 decreased mTORC1 and increased mTORC2 activity in slices from AS mice but inhibited both mTORC1 and mTORC2 in WT mice. Finally, an mTORC2 activator, A-443654, increased hippocampal LTP in AS mice and actin polymerization in both WT and AS mice. Collectively, these results indicate that events set in motion by increased mTORC1 and decreased mTORC2 activities, including increased Arc translation and impaired actin remodeling, are crucial in AS pathogenesis. Therefore, selectively targeting these two master kinase complexes may provide new therapeutic approaches for AS treatment.
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Affiliation(s)
- Jiandong Sun
- Department of Basic Medical Sciences, COMP, Western University of Health Sciences, 701 E. Second Street, Pomona, CA, 91766-1854, USA
| | - Yan Liu
- Graduate College of Biomedical Sciences, Western University of Health Sciences, 701 E. Second Street, Pomona, CA, 91766, USA
| | - Jennifer Tran
- Department of Basic Medical Sciences, COMP, Western University of Health Sciences, 701 E. Second Street, Pomona, CA, 91766-1854, USA
| | - Patrick O'Neal
- Department of Basic Medical Sciences, COMP, Western University of Health Sciences, 701 E. Second Street, Pomona, CA, 91766-1854, USA
| | - Michel Baudry
- Graduate College of Biomedical Sciences, Western University of Health Sciences, 701 E. Second Street, Pomona, CA, 91766, USA
| | - Xiaoning Bi
- Department of Basic Medical Sciences, COMP, Western University of Health Sciences, 701 E. Second Street, Pomona, CA, 91766-1854, USA.
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30
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Tramutola A, Lanzillotta C, Di Domenico F. Targeting mTOR to reduce Alzheimer-related cognitive decline: from current hits to future therapies. Expert Rev Neurother 2016; 17:33-45. [PMID: 27690737 DOI: 10.1080/14737175.2017.1244482] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION The mTOR pathway is involved in the regulation of a wide repertoire of cellular functions in the brain and its dysregulation is emerging as a leitmotif in a large number of neurological disorders. In AD, altered mTOR signaling contributes to the inhibition of autophagy deposition of Aβ and tau aggregates and to the alteration of several neuronal metabolic pathways. Areas covered: In this review, we report all the current findings on the use of mTOR inhibitors (rapamycin, rapalogues) in the treatment of AD. These results support the role of mTOR inhibitors as potential therapeutic agents able to reduce AD hallmarks and recover cognitive performances. Expert commentary: Despite mTOR inhibitors appearing to be ideal compounds to counteract AD, further studies are needed in order to gain knowledge on the involvement of aberrant mTOR in AD, and to standardize a valuable therapeutic approach that can be translated to humans.
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Affiliation(s)
- Antonella Tramutola
- a Department of Biochemical Sciences , Sapienza University of Rome , Rome , Italy
| | - Chiara Lanzillotta
- a Department of Biochemical Sciences , Sapienza University of Rome , Rome , Italy
| | - Fabio Di Domenico
- a Department of Biochemical Sciences , Sapienza University of Rome , Rome , Italy
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