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Wang H, Tang Q, Xue Y, Gao X, Zhang Y. Discovery of drug lead compounds for Anti-Alzheimer's disease on the basis of synaptic plasticity. Heliyon 2023; 9:e18396. [PMID: 37576278 PMCID: PMC10412905 DOI: 10.1016/j.heliyon.2023.e18396] [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: 12/01/2022] [Revised: 07/12/2023] [Accepted: 07/17/2023] [Indexed: 08/15/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease commonly seen in the middle-aged and the elder. Its clinical presentations are mainly memory impairment and cognitive impairment. Its cardinal pathological features are the deposition of extracellular Amyloid-β (Aβ), intracellular neurofibrillary tangles and synaptic dysfunction. The etiology of AD is complex and the pathogenesis remains unclear. Having AD would lead to awful living experience of it's patients, which may be a burden to the patient even to the public health care system. However, there are no certain cure for AD. Thus it's significant for both medical value and social meaning to find the way to cure or prevent AD and to research on the pathogenesis of AD. In this work, the molecular docking technology, pharmacokinetic analysis and pharmacological experiments were employed to analyse the natural active compounds and the mechanisms against AD based on the synaptic plasticity. A total of seven target proteins related to the synaptic plasticity and 44 natural active compounds with potential to enhance the synaptic plasticity were obtained through a literature review and network pharmacological analysis. Computer-Aided Drug Design (CADD) method was used to dock the anti-AD key target proteins with the 44 compounds. The compounds with good binding effect were screened. Three anti-AD active compounds based on the synaptic plasticity were obtained, including Curcumin, Withaferin A and Withanolide A. In addition, pharmacological experiments were carried out on Withaferin A and Withanolide A based on its good docking results. The experimental results showed that Withaferin A has good anti-AD potential and great potential to enhance synaptic plasticity. The anti-AD effect can be achieved through a multi-target synergistic mechanism.
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Affiliation(s)
- Heyu Wang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Quan Tang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Yanyu Xue
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Xiaoqian Gao
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Yan Zhang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
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Karakatsani ME, Ji R, Murillo MF, Kugelman T, Kwon N, Lao YH, Liu K, Pouliopoulos AN, Honig LS, Duff KE, Konofagou EE. Focused ultrasound mitigates pathology and improves spatial memory in Alzheimer's mice and patients. Theranostics 2023; 13:4102-4120. [PMID: 37554284 PMCID: PMC10405840 DOI: 10.7150/thno.79898] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 03/12/2023] [Indexed: 08/10/2023] Open
Abstract
Rationale: Bilateral sonication with focused ultrasound (FUS) in conjunction with microbubbles has been shown to separately reduce amyloid plaques and hyperphosphorylated tau protein in the hippocampal formation and the entorhinal cortex in different mouse models of Alzheimer's disease (AD) without any therapeutic agents. However, the two pathologies are expressed concurrently in human disease. Therefore, the objective of this study is to investigate the effects of repeated bilateral sonications in the presence of both pathologies. Methods: Herein, we investigate its functional and morphological outcomes on brains bearing both pathologies simultaneously. Eleven transgenic mice of the 3xTg-AD line (14 months old) expressing human amyloid beta and human tau and eleven age-matched wild-type littermates received four weekly bilateral sonications covering the hippocampus followed by working memory testing. Afterwards, immunohistochemistry and immunoassays (western blot and ELISA) were employed to assess any changes in amyloid beta and human tau. Furthermore, we present preliminary data from our clinical trial using a neuronavigation-guided FUS system for sonications in AD patients (NCT04118764). Results: Interestingly, both wild-type and transgenic animals that received FUS experienced improved working memory and spent significantly more time in the escape platform-quadrant, with wild-type animals spending 43.2% (sham: 37.7%) and transgenic animals spending 35.3% (sham: 31.0%) of the trial in the target quadrant. Furthermore, this behavioral amelioration in the transgenic animals correlated with a 58.3% decrease in the neuronal length affected by tau and a 27.2% reduction in total tau levels. Amyloid plaque population, volume and overall load were also reduced overall. Consistently, preliminary data from a clinical trial involving AD patients showed a 1.8% decrease of amyloid PET signal 3-weeks after treatment in the treated hemisphere compared to baseline. Conclusion: For the first time, it is shown that bilateral FUS-induced BBB opening significantly and simultaneously ameliorates both coexistent pathologies, which translated to improvements in spatial memory of transgenic animals with complex AD, the human mimicking phenotype. The level of cognitive improvement was significantly correlated with the volume of BBB opening. Non-transgenic animals were also shown to exhibit similar memory amelioration for the first time, indicating that BBB opening results into benefits in the neuronal function regardless of the existence of AD pathology. A potential mechanism of action for the reduction of the both pathologies investigated was the cholesterol metabolism, specifically the LRP1b receptor, which exhibited increased expression levels in transgenic mice following FUS-induced BBB opening. Initial clinical evidence supported that the beta amyloid reduction shown in rodents could be translatable to humans with significant amyloid reduction shown in the treated hemisphere.
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Affiliation(s)
| | - Robin Ji
- Department of Biomedical Engineering, Columbia University, New York, USA
| | - Maria F. Murillo
- Department of Biomedical Engineering, Columbia University, New York, USA
| | - Tara Kugelman
- Department of Biomedical Engineering, Columbia University, New York, USA
| | - Nancy Kwon
- Department of Biomedical Engineering, Columbia University, New York, USA
| | - Yeh-Hsing Lao
- Department of Biomedical Engineering, Columbia University, New York, USA
| | - Keyu Liu
- Department of Biomedical Engineering, Columbia University, New York, USA
| | | | - Lawrence S. Honig
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York, USA
- Department of Neurology, Columbia University Irving Medical Center, New York, USA
| | - Karen E. Duff
- UK Dementia Research Institute, University College London, London, UK
| | - Elisa E. Konofagou
- Department of Radiology, Columbia University Irving Medical Center, New York, USA
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3
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The Molecular Effects of Environmental Enrichment on Alzheimer's Disease. Mol Neurobiol 2022; 59:7095-7118. [PMID: 36083518 PMCID: PMC9616781 DOI: 10.1007/s12035-022-03016-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/23/2022] [Indexed: 12/02/2022]
Abstract
Environmental enrichment (EE) is an environmental paradigm encompassing sensory, cognitive, and physical stimulation at a heightened level. Previous studies have reported the beneficial effects of EE in the brain, particularly in the hippocampus. EE improves cognitive function as well as ameliorates depressive and anxiety-like behaviors, making it a potentially effective neuroprotective strategy against neurodegenerative diseases such as Alzheimer's disease (AD). Here, we summarize the current evidence for EE as a neuroprotective strategy as well as the potential molecular pathways that can explain the effects of EE from a biochemical perspective using animal models. The effectiveness of EE in enhancing brain activity against neurodegeneration is explored with a view to differences present in early and late life EE exposure, with its potential application in human being discussed. We discuss EE as one of the non pharmacological approaches in preventing or delaying the onset of AD for future research.
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Balietti M, Conti F. Environmental enrichment and the aging brain: is it time for standardization? Neurosci Biobehav Rev 2022; 139:104728. [PMID: 35691473 DOI: 10.1016/j.neubiorev.2022.104728] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 05/01/2022] [Accepted: 06/06/2022] [Indexed: 11/30/2022]
Abstract
Aging entails a progressive decline of cognitive abilities. However, since the brain is endowed with considerable plasticity, adequate stimulation can delay or partially compensate for age-related structural and functional impairment. Environmental enrichment (EE) has been reported to determine a wide range of cerebral changes. Although most findings have been obtained in young and adult animals, research has recently turned to aged individuals. Notably, EE can contribute identifying key lifestyle factors whose change can help extend the "mind-span", i.e., the time an individual lives in a healthy cognitive condition. Here we discuss specific methodological issues that can affect the outcomes of EE interventions applied to aged rodents, summarize the main variables that would need standardization (e.g., timing and duration, enrichment items, control animals and setting), and offer some suggestions on how this goal may be achieved. Reaching a consensus on EE experiment design would significantly reduce differences between and within laboratories, enable constructive discussions among researchers, and improve data interpretation.
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Affiliation(s)
- Marta Balietti
- Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy.
| | - Fiorenzo Conti
- Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy; Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy.
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Malcorra BLC, Mota NB, Weissheimer J, Schilling LP, Wilson MA, Hübner LC. Reading and writing habits compensate for aging effects in speech connectedness. NPJ SCIENCE OF LEARNING 2022; 7:13. [PMID: 35676305 PMCID: PMC9178018 DOI: 10.1038/s41539-022-00129-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 05/18/2022] [Indexed: 05/06/2023]
Abstract
We investigate the association of short- and long-range recurrences (speech connectedness) with age, education, and reading and writing habits (RWH) in typical aging using an oral narrative production task. Oral narrative transcriptions were represented as word-graphs to measure short- and long-range recurrences. Speech connectedness was explained by the combination of age, education, and RWH, and the strength of RWH's coefficient reflects the aging effect.
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Affiliation(s)
- Bárbara L C Malcorra
- School of Humanities, Graduate Course in Linguistics, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil.
| | - Natália B Mota
- Institute of Psychiatry, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
- Department of Physics, Federal University of Pernambuco (UFPE), Recife, PE, Brazil
| | - Janaina Weissheimer
- Brain Institute, Department of Foreign Languages and Literatures, Federal University of Rio Grande do Norte (UFRN), Natal, RN, Brazil
- National Council for Scientific and Technological Development (CNPq), Brasília, DF, Brazil
| | - Lucas P Schilling
- School of Medicine, Graduate Course in Medicine and Healthy Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
- School of Medicine, Graduate Course in Biomedical Gerontology, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
- Brain Institute of Rio Grande do Sul (InsCer), Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
| | - Maximiliano A Wilson
- Centre interdisciplinaire de recherche en réadaptation et intégration sociale (CIRRIS), Département de réadaptation, Université Laval, Québec City, QC, Canada
| | - Lilian C Hübner
- School of Humanities, Graduate Course in Linguistics, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
- National Council for Scientific and Technological Development (CNPq), Brasília, DF, Brazil
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Muhammad T, Drishti D, Srivastava S. Prevalence and correlates of vision impairment and its association with cognitive impairment among older adults in India: a cross-sectional study. BMJ Open 2022; 12:e054230. [PMID: 35523503 PMCID: PMC9083423 DOI: 10.1136/bmjopen-2021-054230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE This study aimed to investigate the predictors of vision impairment in old age and how impaired vision is associated with cognitive impairment among the ageing population. DESIGN A cross-sectional study was conducted using a large country-representative survey data. SETTING AND PARTICIPANTS This study used data from the 'Building a Knowledge Base on Population Ageing in India' survey, conducted in 2011. Participants included 9541 older adults aged 60 years and above. PRIMARY AND SECONDARY OUTCOME MEASURES The outcome variables were vision impairment and cognitive impairment. Descriptive statistics along with bivariate analysis were presented. Additionally, multivariable binary logistic regression analysis was performed to fulfil the objectives. RESULTS A proportion of 59.1% of the respondents had vision impairment. Nearly 60% of the participants had cognitive impairment. Those who had vision impairment were 11% more likely to have cognitive impairment compared to their counterparts (OR: 1.11, 95% CI: 1.01 to 1.23). low psychological health (OR: 1.55; 95% CI: 1.36 to 1.77), low activities of daily living (OR: 1.80; 95% CI: 1.43 to 2.27), low instrumental activities of daily living (OR: 1.26; 95% CI: 1.14 to 1.40), poor self-rated health (OR: 1.28; 95% CI: 1.15 to 1.41) and chronic morbidity (OR: 1.27; 95% CI: 1.14 to 1.41) were found to be risk factors for cognitive impairment among older adults. CONCLUSIONS Additional efforts in terms of advocacy, availability, affordability and accessibility especially in a country with big illiteracy issue are mandatory to increase the reach of eye-care services and reduce the prevalence of avoidable visual impairment and vision losses that lead to cognitive deficits among the older population.
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Affiliation(s)
- T Muhammad
- Department of Family & Generations, International Institute for Population Sciences, Mumbai, Maharashtra, India
| | - Drishti Drishti
- Department of Public Health & Mortality Studies, International Institute for Population Sciences, Mumbai, Maharashtra, India
| | - Shobhit Srivastava
- Department of Survey Research & Data Analytics, International Institute for Population Sciences, Mumbai, Maharashtra, India
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Longo V, Barbati SA, Re A, Paciello F, Bolla M, Rinaudo M, Miraglia F, Alù F, Di Donna MG, Vecchio F, Rossini PM, Podda MV, Grassi C. Transcranial Direct Current Stimulation Enhances Neuroplasticity and Accelerates Motor Recovery in a Stroke Mouse Model. Stroke 2022; 53:1746-1758. [PMID: 35291824 DOI: 10.1161/strokeaha.121.034200] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND More effective strategies are needed to promote poststroke functional recovery. Here, we evaluated the impact of bihemispheric transcranial direct current stimulation (tDCS) on forelimb motor function recovery and the underlying mechanisms in mice subjected to focal ischemia of the motor cortex. METHODS Photothrombotic stroke was induced in the forelimb brain motor area, and tDCS was applied once per day for 3 consecutive days, starting 72 hours after stroke. Grid-walking, single pellet reaching, and grip strength tests were conducted to assess motor function. Local field potentials were recorded to evaluate brain connectivity. Western immunoblotting, ELISA, quantitative real-time polymerase chain reaction, and Golgi-Cox staining were used to uncover tDCS-mediated stroke recovery mechanisms. RESULTS Among our results, tDCS increased the rate of motor recovery, anticipating it at the early subacute stage. In this window, tDCS enhanced BDNF (brain-derived neurotrophic factor) expression and dendritic spine density in the peri-infarct motor cortex, along with increasing functional connectivity between motor and somatosensory cortices. Treatment with the BDNF TrkB (tropomyosin-related tyrosine kinase B) receptor inhibitor, ANA-12, prevented tDCS effects on motor recovery and connectivity as well as the increase of spine density, pERK (phosphorylated extracellular signal-regulated kinase), pCaMKII (phosphorylated calcium/calmodulin-dependent protein kinase II), pMEF (phosphorylated myocyte-enhancer factor), and PSD (postsynaptic density)-95. The tDCS-promoted rescue was paralleled by enhanced plasma BDNF level, suggesting its potential role as circulating prognostic biomarker. CONCLUSIONS The rate of motor recovery is accelerated by tDCS applied in the subacute phase of stroke. Anticipation of motor recovery via vicariate pathways or neural reserve recruitment would potentially enhance the efficacy of standard treatments, such as physical therapy, which is often delayed to a later stage when plastic responses are progressively lower.
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Affiliation(s)
- Valentina Longo
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy (V.L., S.A.B., A.R., F.P., M.B., M.R., M.G.D.D., M.V.P., C.G.)
| | - Saviana Antonella Barbati
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy (V.L., S.A.B., A.R., F.P., M.B., M.R., M.G.D.D., M.V.P., C.G.)
| | - Agnese Re
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy (V.L., S.A.B., A.R., F.P., M.B., M.R., M.G.D.D., M.V.P., C.G.)
| | - Fabiola Paciello
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy (V.L., S.A.B., A.R., F.P., M.B., M.R., M.G.D.D., M.V.P., C.G.)
| | - Maria Bolla
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy (V.L., S.A.B., A.R., F.P., M.B., M.R., M.G.D.D., M.V.P., C.G.)
| | - Marco Rinaudo
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy (V.L., S.A.B., A.R., F.P., M.B., M.R., M.G.D.D., M.V.P., C.G.)
| | - Francesca Miraglia
- Brain Connectivity Laboratory, Department of Neuroscience and Neurorehabilitation, IRCCS San Raffaele Roma, Italy (F.M., F.A., F.V., P.M.R.)
| | - Francesca Alù
- Brain Connectivity Laboratory, Department of Neuroscience and Neurorehabilitation, IRCCS San Raffaele Roma, Italy (F.M., F.A., F.V., P.M.R.)
| | - Martina Gaia Di Donna
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy (V.L., S.A.B., A.R., F.P., M.B., M.R., M.G.D.D., M.V.P., C.G.)
| | - Fabrizio Vecchio
- Brain Connectivity Laboratory, Department of Neuroscience and Neurorehabilitation, IRCCS San Raffaele Roma, Italy (F.M., F.A., F.V., P.M.R.).,eCampus University, Novedrate, Como, Italy (F.V.)
| | - Paolo Maria Rossini
- Brain Connectivity Laboratory, Department of Neuroscience and Neurorehabilitation, IRCCS San Raffaele Roma, Italy (F.M., F.A., F.V., P.M.R.)
| | - Maria Vittoria Podda
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy (V.L., S.A.B., A.R., F.P., M.B., M.R., M.G.D.D., M.V.P., C.G.).,Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy (M.V.P., C.G.)
| | - Claudio Grassi
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy (V.L., S.A.B., A.R., F.P., M.B., M.R., M.G.D.D., M.V.P., C.G.).,Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy (M.V.P., C.G.)
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8
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Scabia G, Testa G, Scali M, Del Turco S, Desiato G, Berardi N, Sale A, Matteoli M, Maffei L, Maffei M, Mainardi M. Reduced ccl11/eotaxin mediates the beneficial effects of environmental stimulation on the aged hippocampus. Brain Behav Immun 2021; 98:234-244. [PMID: 34418501 DOI: 10.1016/j.bbi.2021.08.222] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 07/15/2021] [Accepted: 08/13/2021] [Indexed: 02/08/2023] Open
Abstract
A deterioration in cognitive performance accompanies brain aging, even in the absence of neurodegenerative pathologies. However, the rate of cognitive decline can be slowed down by enhanced cognitive and sensorimotor stimulation protocols, such as environmental enrichment (EE). Understanding how EE exerts its beneficial effects on the aged brain pathophysiology can help in identifying new therapeutic targets. In this regard, the inflammatory chemokine ccl11/eotaxin-1 is a marker of aging with a strong relevance for neurodegenerative processes. Here, we demonstrate that EE in both elderly humans and aged mice decreases circulating levels of ccl11. Interfering, in mice, with the ccl11 decrease induced by EE ablated the beneficial effects on long-term memory retention, hippocampal neurogenesis, activation of local microglia and of ribosomal protein S6. On the other hand, treatment of standard-reared aged mice with an anti-ccl11 antibody resulted in EE-like improvements in spatial memory, hippocampal neurogenesis, and microglial activation. Taken together, our findings point to a decrease in circulating ccl11 concentration as a key mediator of the enhanced hippocampal function resulting from exposure to EE.
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Affiliation(s)
- Gaia Scabia
- Institute of Clinical Physiology, National Research Council (IFC-CNR), Pisa, Italy; Obesity and Lipodystrophies Center at Pisa University Hospital, Pisa, Italy
| | - Giovanna Testa
- Laboratory of Biology "Bio@SNS", Scuola Normale Superiore, Pisa, Italy
| | - Manuela Scali
- Institute of Neuroscience, National Research Council (IN-CNR), Pisa, Italy
| | - Serena Del Turco
- Institute of Clinical Physiology, National Research Council (IFC-CNR), Pisa, Italy
| | - Genni Desiato
- Institute of Neuroscience, National Research Council (IN-CNR), Milan, Italy; Humanitas Clinical and Research Center - IRCCS, Rozzano, Milan, Italy
| | - Nicoletta Berardi
- Institute of Neuroscience, National Research Council (IN-CNR), Pisa, Italy; Department of Neuroscience, Psychology, Drug Research and Child Health, NEUROFARBA University of Florence, Florence, Italy
| | - Alessandro Sale
- Institute of Neuroscience, National Research Council (IN-CNR), Pisa, Italy
| | - Michela Matteoli
- Institute of Neuroscience, National Research Council (IN-CNR), Milan, Italy; Humanitas Clinical and Research Center - IRCCS, Rozzano, Milan, Italy
| | - Lamberto Maffei
- Laboratory of Biology "Bio@SNS", Scuola Normale Superiore, Pisa, Italy; Institute of Neuroscience, National Research Council (IN-CNR), Pisa, Italy
| | - Margherita Maffei
- Institute of Clinical Physiology, National Research Council (IFC-CNR), Pisa, Italy; Obesity and Lipodystrophies Center at Pisa University Hospital, Pisa, Italy.
| | - Marco Mainardi
- Laboratory of Biology "Bio@SNS", Scuola Normale Superiore, Pisa, Italy; Institute of Neuroscience, National Research Council (IN-CNR), Pisa, Italy.
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Parameshwaran D, Sathishkumar S, Thiagarajan TC. The impact of socioeconomic and stimulus inequality on human brain physiology. Sci Rep 2021; 11:7439. [PMID: 33811239 PMCID: PMC8018967 DOI: 10.1038/s41598-021-85236-z] [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: 09/27/2020] [Accepted: 02/19/2021] [Indexed: 02/01/2023] Open
Abstract
The brain undergoes profound structural and dynamical alteration in response to its stimulus environment. In animal studies, enriched stimulus environments result in numerous structural and dynamical changes along with cognitive enhancements. In human society factors such as education, travel, cell phones and motorized transport dramatically expand the rate and complexity of stimulus experience but diverge in access based on income. Correspondingly, poverty is associated with significant structural and dynamical differences in the brain, but it is unknown how this relates to disparity in stimulus access. Here we studied consumption of major stimulus factors along with measurement of brain signals using EEG in 402 people in India across an income range of $0.82 to $410/day. We show that the complexity of the EEG signal scaled logarithmically with overall stimulus consumption and income and linearly with education and travel. In contrast phone use jumped up at a threshold of $30/day corresponding to a similar jump in key spectral parameters that reflect the signal energy. Our results suggest that key aspects of brain physiology increase in lockstep with stimulus consumption and that we have not fully appreciated the profound way that stimulus expanding aspects of modern life are changing our brain physiology.
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Affiliation(s)
| | - S. Sathishkumar
- Sapien Labs, 1201 Wilson Drive 27th Floor, Arlington, VA 22209 USA
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10
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Maitre M, Klein C, Patte-Mensah C, Mensah-Nyagan AG. Tryptophan metabolites modify brain Aβ peptide degradation: A role in Alzheimer's disease? Prog Neurobiol 2020; 190:101800. [PMID: 32360535 DOI: 10.1016/j.pneurobio.2020.101800] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 03/30/2020] [Accepted: 04/03/2020] [Indexed: 01/08/2023]
Abstract
Among several processes, a decrease in amyloid-beta (Aβ) peptide elimination is thought to be one of the major pathophysiological factors in Alzheimer's disease (AD). Neprilysin (NEP) is a key metalloproteinase controlling the degradation and clearance of Aβ peptides in the brain. NEP is induced by several pharmacological substances, amyloid deposits and somatostatin, but the physiological regulation of its expression remains unclear. This situation hampers the exploitation of NEP regulatory factors/mechanisms to develop effective strategies against Aβ peptide accumulation-induced brain toxicity. Based on recent data aimed at elucidating this major question, the present paper addresses and critically discusses the role of 5-hydroxyindole-acetic acid (5-HIAA) and kynurenic acid (KYNA) in the regulation of NEP activity/expression in the brain. Both 5-HIAA and KYNA are endogenous metabolites of tryptophan, an essential amino-acid obtained through diet and gut microbiome. By interacting with the aryl hydrocarbon receptor, various tryptophan metabolites modulate several metalloproteinases regulating brain Aβ peptide levels under normal and pathological conditions such as AD. In particular, interesting data reviewed here show that 5-HIAA and KYNA stimulate NEP activity/expression to prevent Aβ peptide-induced neurotoxicity. These data open promising perspectives for the development of tryptophan metabolite-based therapies against AD.
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Affiliation(s)
- Michel Maitre
- Biopathologie de la Myéline, Neuroprotection et Stratégies Thérapeutiques, INSERM U1119, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Bâtiment 3 de la Faculté de Médecine, Strasbourg, France.
| | - Christian Klein
- Biopathologie de la Myéline, Neuroprotection et Stratégies Thérapeutiques, INSERM U1119, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Bâtiment 3 de la Faculté de Médecine, Strasbourg, France
| | - Christine Patte-Mensah
- Biopathologie de la Myéline, Neuroprotection et Stratégies Thérapeutiques, INSERM U1119, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Bâtiment 3 de la Faculté de Médecine, Strasbourg, France
| | - Ayikoe-Guy Mensah-Nyagan
- Biopathologie de la Myéline, Neuroprotection et Stratégies Thérapeutiques, INSERM U1119, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Bâtiment 3 de la Faculté de Médecine, Strasbourg, France.
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11
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Developmental effects of environmental enrichment on selective and auditory sustained attention. Psychoneuroendocrinology 2020; 111:104479. [PMID: 31704636 DOI: 10.1016/j.psyneuen.2019.104479] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 08/23/2019] [Accepted: 10/11/2019] [Indexed: 01/29/2023]
Abstract
Environmental enrichment (EE) has been used as a positive manipulation in different disease models. However, there is conflicting evidence reported in the literature about the effects of EE. Additionally, the time period that would be most beneficial in implementing environmental enrichment as an intervention is not clear. Our study aimed to systematically compare the prenatal, juvenile, mid-adolescence, and adulthood developmental trajectory to further the understanding of enriched environment's effects on selective and auditory sustained attention, corresponding to behavioral (conceived) and physiological-reflexive (non-conceived) measures. Rats were exposed for 21 days to enriched environment during various developmental periods and compared to age-matched controls. All groups were tested for long-term effects (at postnatal day 120 and onward) on selective and sustained attention. We found that the exposure to enriched environment during mid-adolescence has yielded the most significant and long-term pattern of effects, including selective and auditory sustained attention performance, increased foraging-like behavior and a significant decrease in corticosterone level. Similarly, the exposure to EE at juvenile period improved selective attention, increased foraging-like behavior, and reduced anxiety levels as reflected in the open field as well as in low corticosterone levels. These results specify a crucial period along the developmental trajectory for applying environmental enrichment. Mid-adolescence is suggested, in future basic and translational studies, as the sensitive time period that induces the most beneficial and long-term effects of EE on attention. The current findings suggest that the exposure to EE during mid-adolescence should be further considered and studied as behavioral alternative intervention, or as adjuvant behavioral therapy, aimed to decrease the probability to develop ADHD in post-adolescence period. This suggestion is highly relevant due to the debate regarding the pros and cons of screens usage (e.g. Facebook, online games, etc.) during early life that decreases environmental enrichment, especially, direct social interaction.
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Cortical Seizures in FoxG1+/- Mice are Accompanied by Akt/S6 Overactivation, Excitation/Inhibition Imbalance and Impaired Synaptic Transmission. Int J Mol Sci 2019; 20:ijms20174127. [PMID: 31450553 PMCID: PMC6747530 DOI: 10.3390/ijms20174127] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 08/22/2019] [Indexed: 12/14/2022] Open
Abstract
The correct morphofunctional shaping of the cerebral cortex requires a continuous interaction between intrinsic (genes/molecules expressed within the tissue) and extrinsic (e.g., neural activity) factors at all developmental stages. Forkhead Box G1 (FOXG1) is an evolutionarily conserved transcription factor, essential for the cerebral cortex patterning and layering. FOXG1-related disorders, including the congenital form of Rett syndrome, can be caused by deletions, intragenic mutations or duplications. These genetic alterations are associated with a complex phenotypic spectrum, spanning from intellectual disability, microcephaly, to autistic features, and epilepsy. We investigated the functional correlates of dysregulated gene expression by performing electrophysiological assays on FoxG1+/- mice. Local Field Potential (LFP) recordings on freely moving animals detected cortical hyperexcitability. On the other hand, patch-clamp recordings showed a downregulation of spontaneous glutamatergic transmission. These findings were accompanied by overactivation of Akt/S6 signaling. Furthermore, the expression of vesicular glutamate transporter 2 (vGluT2) was increased, whereas the level of the potassium/chloride cotransporter KCC2 was reduced, thus indicating a higher excitation/inhibition ratio. Our findings provide evidence that altered expression of a key gene for cortical development can result in specific alterations in neural circuit function at the macro- and micro-scale, along with dysregulated intracellular signaling and expression of proteins controlling circuit excitability.
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Cline EN, Bicca MA, Viola KL, Klein WL. The Amyloid-β Oligomer Hypothesis: Beginning of the Third Decade. J Alzheimers Dis 2019; 64:S567-S610. [PMID: 29843241 PMCID: PMC6004937 DOI: 10.3233/jad-179941] [Citation(s) in RCA: 543] [Impact Index Per Article: 108.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The amyloid-β oligomer (AβO) hypothesis was introduced in 1998. It proposed that the brain damage leading to Alzheimer’s disease (AD) was instigated by soluble, ligand-like AβOs. This hypothesis was based on the discovery that fibril-free synthetic preparations of AβOs were potent CNS neurotoxins that rapidly inhibited long-term potentiation and, with time, caused selective nerve cell death (Lambert et al., 1998). The mechanism was attributed to disrupted signaling involving the tyrosine-protein kinase Fyn, mediated by an unknown toxin receptor. Over 4,000 articles concerning AβOs have been published since then, including more than 400 reviews. AβOs have been shown to accumulate in an AD-dependent manner in human and animal model brain tissue and, experimentally, to impair learning and memory and instigate major facets of AD neuropathology, including tau pathology, synapse deterioration and loss, inflammation, and oxidative damage. As reviewed by Hayden and Teplow in 2013, the AβO hypothesis “has all but supplanted the amyloid cascade.” Despite the emerging understanding of the role played by AβOs in AD pathogenesis, AβOs have not yet received the clinical attention given to amyloid plaques, which have been at the core of major attempts at therapeutics and diagnostics but are no longer regarded as the most pathogenic form of Aβ. However, if the momentum of AβO research continues, particularly efforts to elucidate key aspects of structure, a clear path to a successful disease modifying therapy can be envisioned. Ensuring that lessons learned from recent, late-stage clinical failures are applied appropriately throughout therapeutic development will further enable the likelihood of a successful therapy in the near-term.
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Affiliation(s)
- Erika N Cline
- Department of Neurobiology, Cognitive Neurology and Alzheimer's Disease Center, International Institute for Nanotechnology, and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
| | - Maíra Assunção Bicca
- Department of Neurobiology, Cognitive Neurology and Alzheimer's Disease Center, International Institute for Nanotechnology, and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
| | - Kirsten L Viola
- Department of Neurobiology, Cognitive Neurology and Alzheimer's Disease Center, International Institute for Nanotechnology, and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
| | - William L Klein
- Department of Neurobiology, Cognitive Neurology and Alzheimer's Disease Center, International Institute for Nanotechnology, and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
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Sujarwoto S, Tampubolon G. Premature natural menopause and cognitive function among older women in Indonesia. J Women Aging 2019; 32:563-577. [PMID: 31057079 DOI: 10.1080/08952841.2019.1607679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We examine the association between premature natural menopause and cognitive function among older women in Indonesia. Data come from Indonesia Family Life Survey (IFLS) 2014 (N = 1,031 menopausal women). Multilevel ordered logistic regression was used to take into account unobserved factors in the women's communities, also considering a range of potential confounding factors including their reproductive histories, lifestyles, and sociodemographic characteristics. The findings show that premature natural menopause was significantly associated with lower cognitive function in later life (ß = -0.97, P< .01, CI -1.61-(-0.33)). The findings were robust against potential confounding factors including reproductive history, lifestyle, and sociodemographic characteristics.
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Affiliation(s)
- Sujarwoto Sujarwoto
- Portsmouth Brawijaya Centre for Global Health, Population and Policy, University of Brawijaya , Malang, Indonesia
| | - Gindo Tampubolon
- The Global Development Institute (GDI), University of Manchester , Lancashire, UK
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Testa G, Mainardi M, Olimpico F, Pancrazi L, Cattaneo A, Caleo M, Costa M. A triheptanoin-supplemented diet rescues hippocampal hyperexcitability and seizure susceptibility in FoxG1 +/- mice. Neuropharmacology 2019; 148:305-310. [PMID: 30639390 DOI: 10.1016/j.neuropharm.2019.01.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 12/11/2018] [Accepted: 01/08/2019] [Indexed: 12/27/2022]
Abstract
The Forkhead Box G1 (FOXG1) gene encodes a transcription factor with an essential role in mammalian telencephalon development. FOXG1-related disorders, caused by deletions, intragenic mutations or duplications, are usually associated with severe intellectual disability, autistic features, and, in 87% of subjects, epileptiform manifestations. In a subset of patients with FoxG1 mutations, seizures remain intractable, prompting the need for novel therapeutic options. To address this issue, we took advantage of a haploinsufficient animal model, the FoxG1+/- mouse. In vivo electrophysiological analyses of FoxG1+/- mice detected hippocampal hyperexcitability, which turned into overt seizures upon delivery of the proconvulsant kainic acid, as confirmed by behavioral observations. These alterations were associated with decreased expression of the chloride transporter KCC2. Next, we tested whether a triheptanoin-based anaplerotic diet could have an impact on the pathological phenotype of FoxG1+/- mice. This manipulation abated altered neural activity and normalized enhanced susceptibility to proconvulsant-induced seizures, in addition to rescuing altered expression of KCC2 and increasing the levels of the GABA transporter vGAT. In conclusion, our data show that FoxG1 haploinsufficiency causes dysfunction of hippocampal circuits and increases the susceptibility to a proconvulsant insult, and that these alterations are rescued by triheptanoin dietary treatment.
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Affiliation(s)
- Giovanna Testa
- Laboratory of Biology "Bio@SNS", Scuola Normale Superiore, Piazza dei Cavalieri, 7, 56124, Pisa, Italy
| | - Marco Mainardi
- Laboratory of Biology "Bio@SNS", Scuola Normale Superiore, Piazza dei Cavalieri, 7, 56124, Pisa, Italy; Institute of Neuroscience, Italian National Research Council (CNR), Via Moruzzi, 1, 56124, Pisa, Italy.
| | - Francesco Olimpico
- Laboratory of Biology "Bio@SNS", Scuola Normale Superiore, Piazza dei Cavalieri, 7, 56124, Pisa, Italy
| | - Laura Pancrazi
- Institute of Neuroscience, Italian National Research Council (CNR), Via Moruzzi, 1, 56124, Pisa, Italy
| | - Antonino Cattaneo
- Laboratory of Biology "Bio@SNS", Scuola Normale Superiore, Piazza dei Cavalieri, 7, 56124, Pisa, Italy
| | - Matteo Caleo
- Laboratory of Biology "Bio@SNS", Scuola Normale Superiore, Piazza dei Cavalieri, 7, 56124, Pisa, Italy; Institute of Neuroscience, Italian National Research Council (CNR), Via Moruzzi, 1, 56124, Pisa, Italy
| | - Mario Costa
- Laboratory of Biology "Bio@SNS", Scuola Normale Superiore, Piazza dei Cavalieri, 7, 56124, Pisa, Italy; Institute of Neuroscience, Italian National Research Council (CNR), Via Moruzzi, 1, 56124, Pisa, Italy.
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Gallo LH, Rodrigues EV, Filho JM, da Silva JB, Harris-Love MO, Gomes ARS. Effects of virtual dance exercise on skeletal muscle architecture and function of community dwelling older women. JOURNAL OF MUSCULOSKELETAL & NEURONAL INTERACTIONS 2019; 19:50-61. [PMID: 30839303 PMCID: PMC6454256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 01/03/2019] [Indexed: 12/05/2022]
Abstract
OBJECTIVES The aim of this study was to analyze the effects of virtual dance exercise on skeletal muscle architecture and function in community-dwelling older women. METHODS Forty-two moderately active older women participated in this study and chose to join either the control group (CG; n=20; 70.3 ± 5.6 years) or exercise group (EG; n=22; 69.3 ± 3.7 years). Participants in the CG maintained their lifestyle and those in the EG performed group dance exercise using Dance Central game for Xbox 360® and Kinect for 40 min, 3 times/week, for 12 weeks. The primary outcomes were: ankle plantar flexion and dorsiflexion peak torque (PT), medial gastrocnemius muscle thickness (MT), fascicle length (FL), and pennation angle (PA). The secondary outcomes were: lower limbs range of motion (ROM), calf circumference (CC), 6 m customary gait speed, and handgrip strength. Data were analyzed using an ANOVA mixed model test (p<0.05). RESULTS EG participants improved plantar flexion PT at 60°/s (16.3%; p<0.01), MT (8.7%; p<0.01) and ankle dorsiflexion ROM (5.1%; p=0.04) when compared to baseline, and exhibited enhanced CC values compared to CG (1.7%; p=0.03). CONCLUSIONS Virtual dance exercise can be recommended to increase muscle mass. Moreover, ankle plantar flexion strength and dorsiflexion ROM gains may contribute to improve functionality and fall avoidance in moderately active older women.
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Affiliation(s)
- Luiza Herminia Gallo
- Physical Education Masters and PhD Programs, Federal University of Parana, Curitiba, Parana, Brazil
| | - Elisângela Valevein Rodrigues
- Physical Education Masters and PhD Programs, Federal University of Parana, Curitiba, Parana, Brazil
- Massage Therapy Department, Federal Institute of Parana, Curitiba, Parana, Brazil
| | - Jarbas Melo Filho
- Physical Education Masters and PhD Programs, Federal University of Parana, Curitiba, Parana, Brazil
| | - Jordana Barbosa da Silva
- Prevention and Rehabilitation in Physiotherapy Department, Federal University of Parana, Curitiba, Parana, Brazil
| | - Michael O. Harris-Love
- Department of Exercise and Nutritional Sciences, Milken Institute School of Public Health, The George Washington University, Washington, DC, USA
| | - Anna Raquel Silveira Gomes
- Physical Education Masters and PhD Programs, Federal University of Parana, Curitiba, Parana, Brazil
- Prevention and Rehabilitation in Physiotherapy Department, Federal University of Parana, Curitiba, Parana, Brazil
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Soluble Aβ Oligomers Impair Dipolar Heterodendritic Plasticity by Activation of mGluR in the Hippocampal CA1 Region. iScience 2018; 6:138-150. [PMID: 30240608 PMCID: PMC6137707 DOI: 10.1016/j.isci.2018.07.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 07/05/2018] [Accepted: 07/19/2018] [Indexed: 11/20/2022] Open
Abstract
Soluble Aβ oligomers (oAβs) contribute importantly to synaptotoxicity in Alzheimer disease (AD), but the mechanisms related to heterogeneity of synaptic functions at local circuits remain elusive. Nearly all studies of the effects of oAβs on hippocampal synaptic plasticity have only examined homosynaptic plasticity. Here we stimulated the Schaffer collaterals and then simultaneously recorded in stratum radiatum (apical dendrites) and stratum oriens (basal dendrites) of CA1 neurons. We found that the apical dendrites are significantly more vulnerable to oAβ-mediated synaptic dysfunction: the heterosynaptic basal dendritic long-term potentiation (LTP) remained unchanged, whereas the homosynaptic apical LTP was impaired. However, the heterosynaptic basal dendritic plasticity induced by either spaced 10-Hz bursts or low-frequency (1-Hz) stimulation was disrupted by oAβs in a mGluR5-dependent manner. These results suggest that different firing patterns in the same neurons may be selectively altered by soluble oAβs in an early phase of AD, before frank neurodegeneration.
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Environmental Enrichment Induces Changes in Long-Term Memory for Social Transmission of Food Preference in Aged Mice through a Mechanism Associated with Epigenetic Processes. Neural Plast 2018; 2018:3725087. [PMID: 30123245 PMCID: PMC6079387 DOI: 10.1155/2018/3725087] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/17/2018] [Accepted: 05/31/2018] [Indexed: 02/06/2023] Open
Abstract
Decline in declarative learning and memory performance is a typical feature of normal aging processes. Exposure of aged animals to an enriched environment (EE) counteracts this decline, an effect correlated with reduction of age-related changes in hippocampal dendritic branching, spine density, neurogenesis, gliogenesis, and neural plasticity, including its epigenetic underpinnings. Declarative memories depend on the medial temporal lobe system, including the hippocampus, for their formation, but, over days to weeks, they become increasingly dependent on other brain regions such as the neocortex and in particular the prefrontal cortex (PFC), a process known as system consolidation. Recently, it has been shown that early tagging of cortical networks is a crucial neurobiological process for remote memory formation and that this tagging involves epigenetic mechanisms in the recipient orbitofrontal (OFC) areas. Whether EE can enhance system consolidation in aged animals has not been tested; in particular, whether the early tagging mechanisms in OFC areas are deficient in aged animals and whether EE can ameliorate them is not known. This study aimed at testing whether EE could affect system consolidation in aged mice using the social transmission of food preference paradigm, which involves an ethologically based form of associative olfactory memory. We found that only EE mice successfully performed the remote memory recall task, showed neuronal activation in OFC, assessed with c-fos immunohistochemistry and early tagging of OFC, assessed with histone H3 acetylation, suggesting a defective system consolidation and early OFC tagging in aged mice which are ameliorated by EE.
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Ikonomovic MD, Abrahamson EE, Carlson SW, Graham SH, Dixon CE. Novel therapies for combating chronic neuropathological sequelae of TBI. Neuropharmacology 2018; 145:160-176. [PMID: 29933008 DOI: 10.1016/j.neuropharm.2018.06.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 06/13/2018] [Accepted: 06/15/2018] [Indexed: 02/06/2023]
Abstract
Traumatic brain injury (TBI) is a risk factor for development of chronic neurodegenerative disorders later in life. This review summarizes the current knowledge and concepts regarding the connection between long-term consequences of TBI and aging-associated neurodegenerative disorders including Alzheimer's disease (AD), chronic traumatic encephalopathy (CTE), and Parkinsonism, with implications for novel therapy targets. Several aggregation-prone proteins such as the amyloid-beta (Aβ) peptides, tau proteins, and α-synuclein protein are involved in secondary pathogenic cascades initiated by a TBI and are also major building blocks of the hallmark pathological lesions in chronic human neurodegenerative diseases with dementia. Impaired metabolism and degradation pathways of aggregation-prone proteins are discussed as potentially critical links between the long-term aftermath of TBI and chronic neurodegeneration. Utility and limitations of previous and current preclinical TBI models designed to study the link between TBI and chronic neurodegeneration, and promising intervention pharmacotherapies and non-pharmacologic strategies to break this link, are also summarized. Complexity of long-term neuropathological consequences of TBI is discussed, with a goal of guiding future preclinical studies and accelerating implementation of promising therapeutics into clinical trials. This article is part of the Special Issue entitled "Novel Treatments for Traumatic Brain Injury".
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Affiliation(s)
- Milos D Ikonomovic
- Geriatric Research Education and Clinical Center, Pittsburgh VA Healthcare System, Pittsburgh, PA, USA; Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
| | - Eric E Abrahamson
- Geriatric Research Education and Clinical Center, Pittsburgh VA Healthcare System, Pittsburgh, PA, USA; Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Shaun W Carlson
- Geriatric Research Education and Clinical Center, Pittsburgh VA Healthcare System, Pittsburgh, PA, USA; Department of Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Steven H Graham
- Geriatric Research Education and Clinical Center, Pittsburgh VA Healthcare System, Pittsburgh, PA, USA; Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - C Edward Dixon
- Geriatric Research Education and Clinical Center, Pittsburgh VA Healthcare System, Pittsburgh, PA, USA; Department of Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Oh H, Razlighi QR, Stern Y. Multiple pathways of reserve simultaneously present in cognitively normal older adults. Neurology 2017; 90:e197-e205. [PMID: 29273689 DOI: 10.1212/wnl.0000000000004829] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 09/27/2017] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To examine neural correlates of intellectual activity underlying multiple pathways imparting reserve by testing that higher intellectual activity is associated with lower brain amyloid pathology, greater gray matter (GM) volume, and differential task-evoked brain activation levels as a function of amyloid positivity status among clinically intact older adults. METHODS Eighty-two cognitively normal older adults and 46 healthy young participants underwent fMRI during task switching. All older participants completed 18F-florbetaben-PET and an individual's amyloid positivity status was determined. To assess GM volume, T1-weighted high-resolution structural images were processed using voxel-based morphometry. As lifestyle factors, intellectual activity was estimated by a composite score of vocabulary, reading ability, and years of education. RESULTS Across all older participants, intellectual activity was associated with lower amyloid deposition in lateral and medial frontoparietal and temporal lobes but higher amyloid deposition in superior frontal and parietal cortices, larger GM volume across widespread brain regions, and reduced brain activation during task switching. These patterns of associations, however, differed by amyloid positivity status. While the patterns of associations remained similar among amyloid-negative older adults, among amyloid-positive older adults, intellectual activity was associated with increased amyloid deposition in frontoparietal cortices and increased activation during task. CONCLUSIONS Intellectual activity simultaneously exerts both neuroprotective and compensatory effects via multiple neural pathways that promote optimal brain aging and help maintain normal cognition during amyloid accumulation.
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Affiliation(s)
- Hwamee Oh
- From the Cognitive Neuroscience Division, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY.
| | - Qolamreza R Razlighi
- From the Cognitive Neuroscience Division, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY
| | - Yaakov Stern
- From the Cognitive Neuroscience Division, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY
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Impact of enriched environment on production of tau, amyloid precursor protein and, amyloid-β peptide in high-fat and high-sucrose-fed rats. Acta Neuropsychiatr 2017; 29:291-298. [PMID: 27923413 DOI: 10.1017/neu.2016.63] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE The Western-type diet is associated with an elevated risk of Alzheimer's disease and other milder forms of cognitive impairment. The aim of the present study was to investigate the effects of the environmental enrichment on amyloid and tau pathology in high-fat and high-sucrose-fed rats. METHODS In total, 40 adult male rats were categorised into two main groups according to their housing conditions: enriched environment (EE, n=16) and standard housing condition (n=24). The groups were further divided into five subgroups that received standard diet, high-fat diet, and high-sucrose diet. We performed the analysis of amyloid β-peptide (Aβ) (1-40), Aβ(1-42), amyloid precursor protein (APP), and tau levels in the hippocampus of rats that were maintained under standard housing conditions or exposed to an EE. RESULTS The EE decreased the Aβ(1-40), Aβ(1-42), APP, and tau levels in high-fat and high-sucrose-fed rats. CONCLUSION This observation shows that EE may rescue diet-induced amyloid and tau pathology.
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Vitamin D 3 protects against Aβ peptide cytotoxicity in differentiated human neuroblastoma SH- SY5Y cells: A role for S1P1/p38MAPK/ATF4 axis. Neuropharmacology 2017; 116:328-342. [PMID: 28077289 DOI: 10.1016/j.neuropharm.2017.01.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 12/23/2016] [Accepted: 01/05/2017] [Indexed: 02/06/2023]
Abstract
Besides its classical function of bone metabolism regulation, 1alpha, 25-dihydroxyvitamin D3 (1,25(OH)2D3), acts on a variety of tissues including the nervous system, where the hormone plays an important role as neuroprotective, antiproliferating and differentiating agent. Sphingolipids are bioactive lipids that play critical and complex roles in regulating cell fate. In the present paper we have investigated whether sphingolipids are involved in the protective action of 1,25(OH)2D3. We have found that 1,25(OH)2D3 prevents amyloid-β peptide (Aβ(1-42)) cytotoxicity both in differentiated SH-SY5Y human neuroblastoma cells and in vivo. In differentiated SH-SY5Y cells, Aβ(1-42) strongly reduces the sphingosine-1-phosphate (S1P)/ceramide (Cer) ratio while 1,25(OH)2D3 partially reverts this effect. 1,25(OH)2D3 reverts also the Aβ(1-42)-induced reduction of sphingosine kinase activity. We have also studied the crosstalk between 1,25(OH)2D3 and S1P signaling pathways downstream to the activation of S1P receptor subtype S1P1. Notably, we found that 1,25(OH)2D3 prevents the reduction of S1P1 expression promoted by Aβ(1-42) and thereby it modulates the downstream signaling leading to ER stress damage (p38MAPK/ATF4). Similar effects were observed by using ZK191784. In addition, chronic treatment with 1,25(OH)2D3 protects from aggregated Aβ(1-42)-induced damage in the CA1 region of the rat hippocampus and promotes cell proliferation in the hippocampal dentate gyrus of adult mice. In conclusion, these results represent the first evidence of the role of 1,25(OH)2D3 and its structural analogue ZK191784 in counteracting the Aβ(1-42) peptide-induced toxicity through the modulation of S1P/S1P1/p38MAPK/ATF4 pathway in differentiated SH-SY5Y cells.
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Petrov AM, Kasimov MR, Zefirov AL. Cholesterol in the Pathogenesis of Alzheimer's, Parkinson's Diseases and Autism: Link to Synaptic Dysfunction. Acta Naturae 2017; 9:26-37. [PMID: 28461971 PMCID: PMC5406657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Indexed: 11/30/2022] Open
Abstract
In our previous review, we described brain cholesterol metabolism in control conditions and in the case of some rare neurological pathologies linked to defects in the genes which are directly involved in the synthesis and/or traffic of cholesterol. Here, we have analyzed disruptions in cholesterol homeostasis in widespread neurodegenerative diseases (Alzheimer's and Parkinson's diseases) and autism spectrum disorders. We particularly focused on the synaptic dysfunctions that could arise from changes in both membrane cholesterol availability and oxysterol production. Notably, alterations in the brain cholesterol metabolism and neurotransmission occur in the early stages of these pathologies and the polymorphism of the genes associated with cholesterol homeostasis and synaptic communication affects the risk of onset and severity of these diseases. In addition, pharmacological and genetic manipulations of brain cholesterol homeostasis in animal models frequently have marked effects on the progression of neurodegenerative diseases. Thus, the development of Alzheimer's, Parkinson's and autism spectrum disorders may be partially associated with an imbalance of cholesterol homeostasis that leads to changes in the membrane cholesterol and oxysterol levels that, in turn, modulates key steps in the synaptic transmission.
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Affiliation(s)
- A. M. Petrov
- Kazan State Medical University, Normal Physiology department, Butlerova str. 49, Kazan, 420012, Russia
| | - M. R. Kasimov
- Kazan State Medical University, Normal Physiology department, Butlerova str. 49, Kazan, 420012, Russia
| | - A. L. Zefirov
- Kazan State Medical University, Normal Physiology department, Butlerova str. 49, Kazan, 420012, Russia
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Gehres SW, Rocha A, Leuzy A, Loss CM, Viola GG, Zimmer ER. Cognitive Intervention As an Early Non-pharmacological Strategy in Alzheimer's Disease: A Translational Perspective. Front Aging Neurosci 2016; 8:280. [PMID: 27965569 PMCID: PMC5126993 DOI: 10.3389/fnagi.2016.00280] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 11/08/2016] [Indexed: 11/13/2022] Open
Affiliation(s)
- Sarah W Gehres
- Department of Biochemistry, Federal University of Rio Grande do Sul Porto Alegre, Brazil
| | - Andreia Rocha
- Department of Biochemistry, Federal University of Rio Grande do Sul Porto Alegre, Brazil
| | - Antoine Leuzy
- Department NVS, Center for Alzheimer Research, Division of Translational Alzheimer Neurobiology, Karolinska Institutet Stockholm, Sweden
| | - Cássio M Loss
- Department of Biochemistry, Federal University of Rio Grande do Sul Porto Alegre, Brazil
| | - Giordano G Viola
- Department of Physiology, Federal University of Sergipe São Cristóvão, Brazil
| | - Eduardo R Zimmer
- Department of Biochemistry, Federal University of Rio Grande do SulPorto Alegre, Brazil; Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do SulPorto Alegre, Brazil
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Koo JH, Kang EB, Oh YS, Yang DS, Cho JY. Treadmill exercise decreases amyloid-β burden possibly via activation of SIRT-1 signaling in a mouse model of Alzheimer's disease. Exp Neurol 2016; 288:142-152. [PMID: 27889467 DOI: 10.1016/j.expneurol.2016.11.014] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/27/2016] [Accepted: 11/22/2016] [Indexed: 02/07/2023]
Abstract
Accumulation of amyloid-β (Aβ) correlates significantly with progressive cognitive deficits, a main symptom of Alzheimer's disease (AD). Although treadmill exercise reduces Aβ levels, the molecular mechanisms underlying the effects are not fully understood. We hypothesize that treadmill exercise decreases Aβ production and alleviates cognitive deficits by activating the non-amyloidogenic pathway via SIRT-1 signaling. Treadmill exercise improved cognitive deficits and alleviated neurotoxicity. Most importantly, treadmill exercise increased SIRT-1 level, which subsequently resulted in increased ADAM-10 level by down-regulation of ROCK-1 and upregulation of RARβ, ultimately facilitating the non-amyloidogenic pathway. Treadmill exercise-induced activation in SIRT-1 level also elevated PGC-1α level and reduced BACE-1 and C-99 level, resulting in inhibition of the amyloidogenic pathway. Treadmill exercise may thus inhibit Aβ production via upregulation of SIRT-1, which biases amyloid precursor protein processing toward the non-amyloidogenic pathway. This study provides novel and valuable insight into the molecular mechanisms possibly by which treadmill exercise reduces Aβ production.
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Affiliation(s)
- Jung-Hoon Koo
- Department of Exercise Biochemistry, Korea National Sport University, Seoul 138-763, Republic of Korea
| | - Eun-Bum Kang
- Department of Exercise Biochemistry, Korea National Sport University, Seoul 138-763, Republic of Korea
| | - Yoo-Sung Oh
- Department of Exercise Prescription, University of Seoul, Seoul 163, Republic of Korea
| | - Dae-Seung Yang
- Department of Taekwondo Studies, University of Gachon, Gyeonggido, Republic of Korea.
| | - Joon-Yong Cho
- Department of Exercise Biochemistry, Korea National Sport University, Seoul 138-763, Republic of Korea.
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Vallone F, Vannini E, Cintio A, Caleo M, Di Garbo A. Time evolution of interhemispheric coupling in a model of focal neocortical epilepsy in mice. Phys Rev E 2016; 94:032409. [PMID: 27739854 DOI: 10.1103/physreve.94.032409] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Indexed: 11/07/2022]
Abstract
Epilepsy is characterized by substantial network rearrangements leading to spontaneous seizures and little is known on how an epileptogenic focus impacts on neural activity in the contralateral hemisphere. Here, we used a model of unilateral epilepsy induced by injection of the synaptic blocker tetanus neurotoxin (TeNT) in the mouse primary visual cortex (V1). Local field potential (LFP) signals were simultaneously recorded from both hemispheres of each mouse in acute phase (peak of toxin action) and chronic condition (completion of TeNT effects). To characterize the neural electrical activities the corresponding LFP signals were analyzed with several methods of time series analysis. For the epileptic mice, the spectral analysis showed that TeNT determines a power redistribution among the different neurophysiological bands in both acute and chronic phases. Using linear and nonlinear interdependence measures in both time and frequency domains, it was found in the acute phase that TeNT injection promotes a reduction of the interhemispheric coupling for high frequencies (12-30 Hz) and small time lag (<20 ms), whereas an increase of the coupling is present for low frequencies (0.5-4 Hz) and long time lag (>40 ms). On the other hand, the chronic period is characterized by a partial or complete recovery of the interhemispheric interdependence level. Granger causality test and symbolic transfer entropy indicate a greater driving influence of the TeNT-injected side on activity in the contralateral hemisphere in the chronic phase. Lastly, based on experimental observations, we built a computational model of LFPs to investigate the role of the ipsilateral inhibition and exicitatory interhemispheric connections in the dampening of the interhemispheric coupling. The time evolution of the interhemispheric coupling in such a relevant model of epilepsy has been addressed here.
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Affiliation(s)
- F Vallone
- Institute of Biophysics, CNR-National Research Council, 56124 Pisa, Italy.,The Biorobotics Institute, Scuola Superiore Sant'Anna, 56026 Pisa, Italy
| | - E Vannini
- Neuroscience Institute, CNR-National Research Council, 56124 Pisa, Italy
| | - A Cintio
- Institute of Biophysics, CNR-National Research Council, 56124 Pisa, Italy
| | - M Caleo
- Neuroscience Institute, CNR-National Research Council, 56124 Pisa, Italy
| | - A Di Garbo
- Institute of Biophysics, CNR-National Research Council, 56124 Pisa, Italy.,INFN-Section of Pisa, 56127 Pisa, Italy
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Petrova MM, Prokopenko SV, Eremina OV, Mozhejko EY, Kaskaeva DS. [Correction of postoperative cognitive dysfunction in cardiosurgery using computer-based stimulation programs]. Zh Nevrol Psikhiatr Im S S Korsakova 2016; 116:35-41. [PMID: 27735897 DOI: 10.17116/jnevro20161169135-41] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
AIM To evaluate the efficacy of computer-based stimulation programs in the correction of postoperative cognitive dysfunction in patients with ischemic heart disease in remote period after coronary artery bypass surgery. MATERIAL AND METHODS The study involved 74 patients. All patients underwent a drug therapy and the rehabilitation course using computer-based stimulation programs (1 time per day for 20 minutes during10 days). Coronary artery bypass surgery was performed for all patients. Patients were examined before operation, after 6 and 12 months. RESULTS The significant improvement of higher cortical functions assessed with the FAB scale, the Schulte test, associated thinking test, ten-word retrieval test at the first attempt, the Clock drawing test) was revealed in the group using computer-based stimulation programs in comparison with the control group. CONCLUSION It is found that rehabilitation course using computer-based stimulation programs in patients with ischemic heart disease after coronary artery bypass surgery is the effective method of cognitive function correction.
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Affiliation(s)
- M M Petrova
- Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk, Russia
| | - S V Prokopenko
- Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk, Russia
| | - O V Eremina
- Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk, Russia
| | - E Yu Mozhejko
- Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk, Russia
| | - D S Kaskaeva
- Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk, Russia
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Cerin E, Rainey-Smith SR, Ames D, Lautenschlager NT, Macaulay SL, Fowler C, Robertson JS, Rowe CC, Maruff P, Martins RN, Masters CL, Ellis KA. Associations of neighborhood environment with brain imaging outcomes in the Australian Imaging, Biomarkers and Lifestyle cohort. Alzheimers Dement 2016; 13:388-398. [PMID: 27546307 DOI: 10.1016/j.jalz.2016.06.2364] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 06/10/2016] [Accepted: 06/23/2016] [Indexed: 10/21/2022]
Abstract
INTRODUCTION "Walkable" neighborhoods offer older adults opportunities for activities that may benefit cognition-related biological mechanisms. These have not previously been examined in this context. METHODS We objectively assessed neighborhood walkability for participants (n = 146) from the Australian Imaging, Biomarkers and Lifestyle study with apolipoprotein E (APOE) genotype and two 18-month-apart brain volumetric and/or amyloid β burden assessments. Linear mixed models estimated associations of neighborhood walkability with levels and changes in brain imaging outcomes, the moderating effect of APOE ε4 status, and the extent to which associations were explained by physical activity. RESULTS Cross-sectionally, neighborhood walkability was predictive of better neuroimaging outcomes except for left hippocampal volume. These associations were to a small extent explained by physical activity. APOE ε4 carriers showed slower worsening of outcomes if living in walkable neighborhoods. DISCUSSION These findings indicate associations between neighborhood walkability and brain imaging measures (especially in APOE ε4 carriers) minimally attributable to physical activity.
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Affiliation(s)
- Ester Cerin
- Institute for Health and Ageing, Australian Catholic University, Melbourne, Victoria, Australia; School of Public Health, The University of Hong Kong, Hong Kong, China; School of Exercise and Nutrition Sciences, Deakin University, Burwood, Victoria, Australia.
| | - Stephanie R Rainey-Smith
- Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia; Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Perth, Western Australia, Australia
| | - David Ames
- Academic Unit for Psychiatry of Old Age, Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia; National Ageing Research Institute, Parkville, Victoria, Australia
| | - Nicola T Lautenschlager
- Academic Unit for Psychiatry of Old Age, Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Christopher Fowler
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Joanne S Robertson
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Paul Maruff
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia; Cogstate Ltd., Melbourne, Victoria, Australia
| | - Ralph N Martins
- Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia; Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Perth, Western Australia, Australia
| | - Colin L Masters
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Kathryn A Ellis
- Academic Unit for Psychiatry of Old Age, Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia
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Sansevero G, Begenisic T, Mainardi M, Sale A. Experience-dependent reduction of soluble β-amyloid oligomers and rescue of cognitive abilities in middle-age Ts65Dn mice, a model of Down syndrome. Exp Neurol 2016; 283:49-56. [PMID: 27288239 DOI: 10.1016/j.expneurol.2016.06.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 05/30/2016] [Accepted: 06/06/2016] [Indexed: 11/17/2022]
Abstract
Down syndrome (DS) is the most diffused genetic cause of intellectual disability and, after the age of forty, is invariantly associated with Alzheimer's disease (AD). In the last years, the prolongation of life expectancy in people with DS renders the need for intervention paradigms aimed at improving mental disability and counteracting AD pathology particularly urgent. At present, however, there are no effective therapeutic strategies for DS and concomitant AD in mid-life people. The most intensively studied mouse model of DS is the Ts65Dn line, which summarizes the main hallmarks of the DS phenotype, included severe learning and memory deficits and age-dependent AD-like pathology. Here we report for the first time that middle-age Ts65Dn mice display a marked increase in soluble Aβ oligomer levels in their hippocampus. Moreover, we found that long-term exposure to environmental enrichment (EE), a widely used paradigm that increases sensory-motor stimulation, reduces Aβ oligomers and rescues spatial memory abilities in trisomic mice. Our findings underscore the potential of EE procedures as a non-invasive paradigm for counteracting brain aging processes in DS subjects.
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Affiliation(s)
- Gabriele Sansevero
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy; NEUROFARBA, University of Florence, Florence, Italy
| | - Tatjana Begenisic
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy
| | - Marco Mainardi
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy
| | - Alessandro Sale
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy.
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Stein LR, O'Dell KA, Funatsu M, Zorumski CF, Izumi Y. Short-term environmental enrichment enhances synaptic plasticity in hippocampal slices from aged rats. Neuroscience 2016; 329:294-305. [PMID: 27208617 DOI: 10.1016/j.neuroscience.2016.05.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Revised: 05/11/2016] [Accepted: 05/12/2016] [Indexed: 12/26/2022]
Abstract
Age-associated changes in cognition are mirrored by impairments in cellular models of memory and learning, such as long-term potentiation (LTP) and long-term depression (LTD). In young rodents, environmental enrichment (EE) can enhance memory, alter LTP and LTD, as well as reverse cognitive deficits induced by aging. Whether short-term EE can benefit cognition and synaptic plasticity in aged rodents is unclear. Here, we tested if short-term EE could overcome age-associated impairments in induction of LTP and LTD. LTP and LTD could not be induced in the CA1 region of hippocampal slices in control, aged rats using standard stimuli that are highly effective in young rats. However, exposure of aged littermates to EE for three weeks enabled successful induction of LTP and LTD. EE-facilitated LTP was dependent upon N-methyl-d-aspartate receptors (NMDARs). These alterations in synaptic plasticity occurred with elevated levels of phosphorylated cAMP response element-binding protein and vascular endothelial growth factor, but in the absence of changes in several other synaptic and cellular markers. Importantly, our study suggests that even a relatively short period of EE is sufficient to alter synaptic plasticity and molecular markers linked to cognitive function in aged animals.
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Affiliation(s)
- Liana R Stein
- Department of Psychiatry, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA
| | - Kazuko A O'Dell
- Department of Psychiatry, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA
| | - Michiyo Funatsu
- Department of Psychiatry, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA
| | - Charles F Zorumski
- Department of Psychiatry, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA; Center for Brain Research in Mood Disorders, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA; Department of Neuroscience, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA
| | - Yukitoshi Izumi
- Department of Psychiatry, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA; Center for Brain Research in Mood Disorders, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
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31
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Montgomery KS, Edwards G, Levites Y, Kumar A, Myers CE, Gluck MA, Setlow B, Bizon JL. Deficits in hippocampal-dependent transfer generalization learning accompany synaptic dysfunction in a mouse model of amyloidosis. Hippocampus 2016; 26:455-71. [PMID: 26418152 PMCID: PMC4803574 DOI: 10.1002/hipo.22535] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 09/11/2015] [Accepted: 09/17/2015] [Indexed: 11/08/2022]
Abstract
Elevated β-amyloid and impaired synaptic function in hippocampus are among the earliest manifestations of Alzheimer's disease (AD). Most cognitive assessments employed in both humans and animal models, however, are insensitive to this early disease pathology. One critical aspect of hippocampal function is its role in episodic memory, which involves the binding of temporally coincident sensory information (e.g., sights, smells, and sounds) to create a representation of a specific learning epoch. Flexible associations can be formed among these distinct sensory stimuli that enable the "transfer" of new learning across a wide variety of contexts. The current studies employed a mouse analog of an associative "transfer learning" task that has previously been used to identify risk for prodromal AD in humans. The rodent version of the task assesses the transfer of learning about stimulus features relevant to a food reward across a series of compound discrimination problems. The relevant feature that predicts the food reward is unchanged across problems, but an irrelevant feature (i.e., the context) is altered. Experiment 1 demonstrated that C57BL6/J mice with bilateral ibotenic acid lesions of hippocampus were able to discriminate between two stimuli on par with control mice; however, lesioned mice were unable to transfer or apply this learning to new problem configurations. Experiment 2 used the APPswe PS1 mouse model of amyloidosis to show that robust impairments in transfer learning are evident in mice with subtle β-amyloid-induced synaptic deficits in the hippocampus. Finally, Experiment 3 confirmed that the same transfer learning impairments observed in APPswePS1 mice were also evident in the Tg-SwDI mouse, a second model of amyloidosis. Together, these data show that the ability to generalize learned associations to new contexts is disrupted even in the presence of subtle hippocampal dysfunction and suggest that, across species, this aspect of hippocampal-dependent learning may be useful for early identification of AD-like pathology.
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Affiliation(s)
- Karienn S. Montgomery
- Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center, Bryan, TX
| | - George Edwards
- Mitchell Center for Alzheimer’s Disease and Related Brain Disorders, Department of Neurology, University of Texas Health Science Center in Houston, Houston, TX
| | - Yona Levites
- Department of Neuroscience, University of Florida, Gainesville, FL
| | - Ashok Kumar
- Department of Neuroscience, University of Florida, Gainesville, FL
| | - Catherine E. Myers
- VA New Jersey Health Care System, East Orange, NJ 07018
- Department of Pharmacology, Physiology & Neuroscience, New Jersey Medical School, Rutgers University, Newark, NJ
| | - Mark A. Gluck
- Center for Molecular & Behavioral Neuroscience, Rutgers University, Newark, NJ
| | - Barry Setlow
- Department of Psychiatry, University of Florida, Gainesville, FL
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Vallone F, Lai S, Spalletti C, Panarese A, Alia C, Micera S, Caleo M, Di Garbo A. Post-Stroke Longitudinal Alterations of Inter-Hemispheric Correlation and Hemispheric Dominance in Mouse Pre-Motor Cortex. PLoS One 2016; 11:e0146858. [PMID: 26752066 PMCID: PMC4709093 DOI: 10.1371/journal.pone.0146858] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 12/21/2015] [Indexed: 11/19/2022] Open
Abstract
Purpose Limited restoration of function is known to occur spontaneously after an ischemic injury to the primary motor cortex. Evidence suggests that Pre-Motor Areas (PMAs) may “take over” control of the disrupted functions. However, little is known about functional reorganizations in PMAs. Forelimb movements in mice can be driven by two cortical regions, Caudal and Rostral Forelimb Areas (CFA and RFA), generally accepted as primary motor and pre-motor cortex, respectively. Here, we examined longitudinal changes in functional coupling between the two RFAs following unilateral photothrombotic stroke in CFA (mm from Bregma: +0.5 anterior, +1.25 lateral). Methods Local field potentials (LFPs) were recorded from the RFAs of both hemispheres in freely moving injured and naïve mice. Neural signals were acquired at 9, 16 and 23 days after surgery (sub-acute period in stroke animals) through one bipolar electrode per hemisphere placed in the center of RFA, with a ground screw over the occipital bone. LFPs were pre-processed through an efficient method of artifact removal and analysed through: spectral,cross-correlation, mutual information and Granger causality analysis. Results Spectral analysis demonstrated an early decrease (day 9) in the alpha band power in both the RFAs. In the late sub-acute period (days 16 and 23), inter-hemispheric functional coupling was reduced in ischemic animals, as shown by a decrease in the cross-correlation and mutual information measures. Within the gamma and delta bands, correlation measures were already reduced at day 9. Granger analysis, used as a measure of the symmetry of the inter-hemispheric causal connectivity, showed a less balanced activity in the two RFAs after stroke, with more frequent oscillations of hemispheric dominance. Conclusions These results indicate robust electrophysiological changes in PMAs after stroke. Specifically, we found alterations in transcallosal connectivity, with reduced inter-hemispheric functional coupling and a fluctuating dominance pattern. These reorganizations may underlie vicariation of lost functions following stroke.
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Affiliation(s)
- Fabio Vallone
- Institute of Biophysics, CNR, Pisa, Italy
- Translational Neural Engineering Area, The Biorobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy
| | - Stefano Lai
- Translational Neural Engineering Area, The Biorobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy
| | - Cristina Spalletti
- Neuroscience Institute, CNR, Pisa, Italy
- Life Science Institute, Scuola Superiore Sant’Anna, Pisa, Italy
| | - Alessandro Panarese
- Translational Neural Engineering Area, The Biorobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy
| | | | - Silvestro Micera
- Translational Neural Engineering Area, The Biorobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy
- Bertarelli Foundation Chair in Translational Neuroengineering Center for Neuroprosthetics and Institute of Bioengineering School of Engineering Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland
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Castrillo JI, Oliver SG. Alzheimer's as a Systems-Level Disease Involving the Interplay of Multiple Cellular Networks. Methods Mol Biol 2016; 1303:3-48. [PMID: 26235058 DOI: 10.1007/978-1-4939-2627-5_1] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Alzheimer's disease (AD), and many neurodegenerative disorders, are multifactorial in nature. They involve a combination of genomic, epigenomic, interactomic and environmental factors. Progress is being made, and these complex diseases are beginning to be understood as having their origin in altered states of biological networks at the cellular level. In the case of AD, genomic susceptibility and mechanisms leading to (or accompanying) the impairment of the central Amyloid Precursor Protein (APP) processing and tau networks are widely accepted as major contributors to the diseased state. The derangement of these networks may result in both the gain and loss of functions, increased generation of toxic species (e.g., toxic soluble oligomers and aggregates) and imbalances, whose effects can propagate to supra-cellular levels. Although well sustained by empirical data and widely accepted, this global perspective often overlooks the essential roles played by the main counteracting homeostatic networks (e.g., protein quality control/proteostasis, unfolded protein response, protein folding chaperone networks, disaggregases, ER-associated degradation/ubiquitin proteasome system, endolysosomal network, autophagy, and other stress-protective and clearance networks), whose relevance to AD is just beginning to be fully realized. In this chapter, an integrative perspective is presented. Alzheimer's disease is characterized to be a result of: (a) intrinsic genomic/epigenomic susceptibility and, (b) a continued dynamic interplay between the deranged networks and the central homeostatic networks of nerve cells. This interplay of networks will underlie both the onset and rate of progression of the disease in each individual. Integrative Systems Biology approaches are required to effect its elucidation. Comprehensive Systems Biology experiments at different 'omics levels in simple model organisms, engineered to recapitulate the basic features of AD may illuminate the onset and sequence of events underlying AD. Indeed, studies of models of AD in simple organisms, differentiated cells in culture and rodents are beginning to offer hope that the onset and progression of AD, if detected at an early stage, may be stopped, delayed, or even reversed, by activating or modulating networks involved in proteostasis and the clearance of toxic species. In practice, the incorporation of next-generation neuroimaging, high-throughput and computational approaches are opening the way towards early diagnosis well before irreversible cell death. Thus, the presence or co-occurrence of: (a) accumulation of toxic Aβ oligomers and tau species; (b) altered splicing and transcriptome patterns; (c) impaired redox, proteostatic, and metabolic networks together with, (d) compromised homeostatic capacities may constitute relevant 'AD hallmarks at the cellular level' towards reliable and early diagnosis. From here, preventive lifestyle changes and tailored therapies may be investigated, such as combined strategies aimed at both lowering the production of toxic species and potentiating homeostatic responses, in order to prevent or delay the onset, and arrest, alleviate, or even reverse the progression of the disease.
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Affiliation(s)
- Juan I Castrillo
- Department of Biochemistry & Cambridge Systems Biology Centre, University of Cambridge, Sanger Building, 80 Tennis Court Road, Cambridge, CB2 1GA, UK,
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Kentner AC. Neuroprotection and recovery from early-life adversity: considerations for environmental enrichment. Neural Regen Res 2015; 10:1545-7. [PMID: 26692834 PMCID: PMC4660730 DOI: 10.4103/1673-5374.165315] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Amanda C Kentner
- School of Arts & Sciences, Health Psychology Program, MCPHS University (formerly Massachusetts College of Pharmacy & Health Sciences), Boston, MA, USA
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35
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Sun MK, Nelson TJ, Alkon DL. Towards universal therapeutics for memory disorders. Trends Pharmacol Sci 2015; 36:384-94. [DOI: 10.1016/j.tips.2015.04.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 04/07/2015] [Accepted: 04/08/2015] [Indexed: 12/22/2022]
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36
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Hung SC, Liao KF, Muo CH, Lai SW, Chang CW, Hung HC. Hearing Loss is Associated With Risk of Alzheimer's Disease: A Case-Control Study in Older People. J Epidemiol 2015; 25:517-21. [PMID: 25986155 PMCID: PMC4517989 DOI: 10.2188/jea.je20140147] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Background It remains unknown whether hearing loss increases the risk of Alzheimer’s disease. This study aimed to examine the association between hearing loss and risk of Alzheimer’s disease in older people in Taiwan. Methods Analyzing the database from Taiwan’s National Health Insurance Program, this case-control study enrolled 488 subjects ≥65 years old with newly diagnosed Alzheimer’s disease as a case group and 1952 subjects without Alzheimer’s disease as a control group from 1998–2011. Patients with Alzheimer’s disease and other comorbidities were identified by analyzing ICD-9 coding in claims data. The association of hearing loss, other comorbidities, and risk of Alzheimer’s disease were compared between groups. Results After controlling for confounders, multivariable logistic regression showed an adjusted odds ratio of Alzheimer’s disease of 1.39 in people with hearing loss (95% CI, 1.05–1.84) versus those without. Parkinson’s disease (OR 4.44; 95% CI, 2.54–7.78), head injury (OR 2.31; 95% CI, 1.46–3.66), depression (OR 1.68; 95% CI, 1.19–2.39), hypertension (OR 1.40; 95% CI, 1.10–1.79), and age (each year, OR 1.03; 95% CI, 1.01–1.05) also showed strong links with Alzheimer’s. Conclusions Hearing loss is associated with increased risk of Alzheimer’s disease in older people in Taiwan.
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Modulation of hippocampal neural plasticity by glucose-related signaling. Neural Plast 2015; 2015:657928. [PMID: 25977822 PMCID: PMC4419237 DOI: 10.1155/2015/657928] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 04/02/2015] [Accepted: 04/05/2015] [Indexed: 12/20/2022] Open
Abstract
Hormones and peptides involved in glucose homeostasis are emerging as important modulators of neural plasticity. In this regard, increasing evidence shows that molecules such as insulin, insulin-like growth factor-I, glucagon-like peptide-1, and ghrelin impact on the function of the hippocampus, which is a key area for learning and memory. Indeed, all these factors affect fundamental hippocampal properties including synaptic plasticity (i.e., synapse potentiation and depression), structural plasticity (i.e., dynamics of dendritic spines), and adult neurogenesis, thus leading to modifications in cognitive performance. Here, we review the main mechanisms underlying the effects of glucose metabolism on hippocampal physiology. In particular, we discuss the role of these signals in the modulation of cognitive functions and their potential implications in dysmetabolism-related cognitive decline.
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Viola KL, Klein WL. Amyloid β oligomers in Alzheimer's disease pathogenesis, treatment, and diagnosis. Acta Neuropathol 2015; 129:183-206. [PMID: 25604547 DOI: 10.1007/s00401-015-1386-3] [Citation(s) in RCA: 440] [Impact Index Per Article: 48.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 01/11/2015] [Accepted: 01/11/2015] [Indexed: 12/22/2022]
Abstract
Protein aggregation is common to dozens of diseases including prionoses, diabetes, Parkinson's and Alzheimer's. Over the past 15 years, there has been a paradigm shift in understanding the structural basis for these proteinopathies. Precedent for this shift has come from investigation of soluble Aβ oligomers (AβOs), toxins now widely regarded as instigating neuron damage leading to Alzheimer's dementia. Toxic AβOs accumulate in AD brain and constitute long-lived alternatives to the disease-defining Aβ fibrils deposited in amyloid plaques. Key experiments using fibril-free AβO solutions demonstrated that while Aβ is essential for memory loss, the fibrillar Aβ in amyloid deposits is not the agent. The AD-like cellular pathologies induced by AβOs suggest their impact provides a unifying mechanism for AD pathogenesis, explaining why early stage disease is specific for memory and accounting for major facets of AD neuropathology. Alternative ideas for triggering mechanisms are being actively investigated. Some research favors insertion of AβOs into membrane, while other evidence supports ligand-like accumulation at particular synapses. Over a dozen candidate toxin receptors have been proposed. AβO binding triggers a redistribution of critical synaptic proteins and induces hyperactivity in metabotropic and ionotropic glutamate receptors. This leads to Ca(2+) overload and instigates major facets of AD neuropathology, including tau hyperphosphorylation, insulin resistance, oxidative stress, and synapse loss. Because different species of AβOs have been identified, a remaining question is which oligomer is the major pathogenic culprit. The possibility has been raised that more than one species plays a role. Despite some key unknowns, the clinical relevance of AβOs has been established, and new studies are beginning to point to co-morbidities such as diabetes and hypercholesterolemia as etiological factors. Because pathogenic AβOs appear early in the disease, they offer appealing targets for therapeutics and diagnostics. Promising therapeutic strategies include use of CNS insulin signaling enhancers to protect against the presence of toxins and elimination of the toxins through use of highly specific AβO antibodies. An AD-dependent accumulation of AβOs in CSF suggests their potential use as biomarkers and new AβO probes are opening the door to brain imaging. Overall, current evidence indicates that Aβ oligomers provide a substantive molecular basis for the cause, treatment and diagnosis of Alzheimer's disease.
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Transformation of cortical and hippocampal neural circuit by environmental enrichment. Neuroscience 2014; 280:282-98. [PMID: 25242640 DOI: 10.1016/j.neuroscience.2014.09.031] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 09/10/2014] [Accepted: 09/10/2014] [Indexed: 12/17/2022]
Abstract
It has been half a century since brain volume enlargement was first reported in animals reared in an enriched environment (EE). As EE animals show improved memory task performance, exposure to EE has been a useful model system for studying the effects of experience on brain plasticity. We review EE-induced neural changes in the cerebral cortex and hippocampus focusing mainly on works published in the recent decade. The review is organized in three large domains of changes: anatomical, electrophysiological, and molecular changes. Finally, we discuss open issues and future outlook toward better understanding of EE-induced neural changes.
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Nalivaeva NN, Belyaev ND, Kerridge C, Turner AJ. Amyloid-clearing proteins and their epigenetic regulation as a therapeutic target in Alzheimer's disease. Front Aging Neurosci 2014; 6:235. [PMID: 25278875 PMCID: PMC4166351 DOI: 10.3389/fnagi.2014.00235] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 08/18/2014] [Indexed: 12/21/2022] Open
Abstract
Abnormal elevation of amyloid β-peptide (Aβ) levels in the brain is the primary trigger for neuronal cell death specific to Alzheimer’s disease (AD). It is now evident that Aβ levels in the brain are manipulable due to a dynamic equilibrium between its production from the amyloid precursor protein (APP) and removal by amyloid clearance proteins. Clearance can be either enzymic or non-enzymic (binding/transport proteins). Intriguingly several of the main amyloid-degrading enzymes (ADEs) are members of the M13 peptidase family (neprilysin (NEP), NEP2 and the endothelin converting enzymes (ECE-1 and -2)). A distinct metallopeptidase, insulin-degrading enzyme (IDE), also contributes to Aβ degradation in the brain. The ADE family currently embraces more than 20 members, both membrane-bound and soluble, and of differing cellular locations. NEP plays an important role in brain function terminating neuropeptide signals. Its decrease in specific brain areas with age or after hypoxia, ischaemia or stroke contribute significantly to the development of AD pathology. The recently discovered mechanism of epigenetic regulation of NEP (and other genes) by the APP intracellular domain (AICD) and its dependence on the cell type and APP isoform expression suggest possibilities for selective manipulation of NEP gene expression in neuronal cells. We have also observed that another amyloid-clearing protein, namely transthyretin (TTR), is also regulated in the neuronal cell by a mechanism similar to NEP. Dependence of amyloid clearance proteins on histone deacetylases and the ability of HDAC inhibitors to up-regulate their expression in the brain opens new avenues for developing preventive strategies in AD.
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Affiliation(s)
- Natalia N Nalivaeva
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds Leed, UK ; I.M.Sechenov Institute of Evolutionary Physiology and Biochemistry St. Petersburg, Russia
| | - Nikolai D Belyaev
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds Leed, UK
| | - Caroline Kerridge
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds Leed, UK ; Neurodegeneration DHT, Lilly, Erl Wood Manor Windlesham, Surrey, UK
| | - Anthony J Turner
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds Leed, UK
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