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Soytürk H, Önal C, Kılıç Ü, Türkoğlu ŞA, Ayaz E. The effect of the HMGB1/RAGE/TLR4/NF-κB signalling pathway in patients with idiopathic epilepsy and its relationship with toxoplasmosis. J Cell Mol Med 2024; 28:e18542. [PMID: 39046369 DOI: 10.1111/jcmm.18542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2024] [Revised: 06/28/2024] [Accepted: 07/13/2024] [Indexed: 07/25/2024] Open
Abstract
This study aims to investigate the relationship between toxoplasmosis and this pathway, which may be effective in the formation of epilepsy by acting through the HMGB1/RAGE/TLR4/NF-κB signalling pathway in patients with idiopathic epilepsy. In the study, four different experimental groups were formed by selecting Toxoplasma gondii IgG positive and negative patients with idiopathic epilepsy and healthy controls. Experimental groups were as follows: Group 1: Epilepsy+/Toxo- (E+, T-) (n = 10), Group 2: Epilepsy-/Toxo- (E-, T-) (n = 10), Group 3: Epilepsy-/Toxo+ (E-, T+) (n = 10), Group 4: Epilepsy+/Toxo+ (E+, T+) (n = 10). HMGB1, RAGE, TLR4, TLR1, TLR2, TLR3, IRAK1, IRAK2, IKBKB, IKBKG, BCL3, IL1β, IL10, 1 L8 and TNFα mRNA expression levels in the HMGB/RAGE/TLR4/NF-κB signalling pathway were determined by quantitative simultaneous PCR (qRT-PCR) after collecting blood samples from all patients in the groups. Statistical analysis was performed by one-way ANOVA followed by LSD post-hoc tests, and p < 0.05 was considered to denote statistical significance. The gene expression levels of HMGB1, TLR4, IL10, IL1B, IL8, and TLR2 were significantly higher in the G1 group than in the other groups (p < 0.05). In the G3 group, RAGE and BCL3 gene expression levels were significantly higher than in the other groups (p < 0.05). In the G4 group, however, IRAK2, IKBKB, and IKBKG gene expression levels were significantly higher than in the other groups (p < 0.05). HMGB1, TLR4, IRAK2, IKBKB, IL10, IL1B, IL1B, and IL8 in this signalling pathway are highly expressed in epilepsy patients in G1 and seizures occur with the stimulation of excitatory mechanisms by acting through this pathway. The signalling pathway in epilepsy may be activated by HMGB1, TLR4, and TLR2, which are considered to increase the level of proinflammatory cytokines. In T. gondii, this pathway is activated by RAGE and BCL3.
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Affiliation(s)
- Hayriye Soytürk
- Bolu Abant Izzet Baysal University, Institute of Graduate Studies Interdisciplinary Neuroscience, Bolu, Turkey
| | - Cansu Önal
- Zonguldak Bülent Ecevit University, Department of Molecular Biology and Genetics, Faculty of Science, Zonguldak, Turkey
| | - Ümit Kılıç
- Duzce University Vocational School of Health Services, Duzce, Turkey
| | - Şule Aydın Türkoğlu
- Department of Neurology, Faculty of Medicine, Bolu Abant Izzet Baysal University, Bolu, Turkey
| | - Erol Ayaz
- Department of Parasitology, Faculty of Medicine, Bolu Abant Izzet Baysal University, Bolu, Turkey
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Lisgaras CP, Scharfman HE. Interictal spikes in Alzheimer's disease: Preclinical evidence for dominance of the dentate gyrus and cholinergic control by the medial septum. Neurobiol Dis 2023; 187:106294. [PMID: 37714307 PMCID: PMC10617404 DOI: 10.1016/j.nbd.2023.106294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 09/11/2023] [Accepted: 09/13/2023] [Indexed: 09/17/2023] Open
Abstract
Interictal spikes (IIS) are a common type of abnormal electrical activity in Alzheimer's disease (AD) and preclinical models. The brain regions where IIS are largest are not known but are important because such data would suggest sites that contribute to IIS generation. Because hippocampus and cortex exhibit altered excitability in AD models, we asked which areas dominate the activity during IIS along the cortical-CA1-dentate gyrus (DG) dorso-ventral axis. Because medial septal (MS) cholinergic neurons are overactive when IIS typically occur, we also tested the novel hypothesis that silencing the MS cholinergic neurons selectively would reduce IIS. We used mice that simulate aspects of AD: Tg2576 mice, presenilin 2 (PS2) knockout mice and Ts65Dn mice. To selectively silence MS cholinergic neurons, Tg2576 mice were bred with choline-acetyltransferase (ChAT)-Cre mice and offspring were injected in the MS with AAV encoding inhibitory designer receptors exclusively activated by designer drugs (DREADDs). We recorded local field potentials along the cortical-CA1-DG axis using silicon probes during wakefulness, slow-wave sleep (SWS) and rapid eye movement (REM) sleep. We detected IIS in all transgenic or knockout mice but not age-matched controls. IIS were detectable throughout the cortical-CA1-DG axis and occurred primarily during REM sleep. In all 3 mouse lines, IIS amplitudes were significantly greater in the DG granule cell layer vs. CA1 pyramidal layer or overlying cortex. Current source density analysis showed robust and early current sources in the DG, and additional sources in CA1 and the cortex also. Selective chemogenetic silencing of MS cholinergic neurons significantly reduced IIS rate during REM sleep without affecting the overall duration, number of REM bouts, latency to REM sleep, or theta power during REM. Notably, two control interventions showed no effects. Consistent maximal amplitude and strong current sources of IIS in the DG suggest that the DG is remarkably active during IIS. In addition, selectively reducing MS cholinergic tone, at times when MS is hyperactive, could be a new strategy to reduce IIS in AD.
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Affiliation(s)
- Christos Panagiotis Lisgaras
- Departments of Child & Adolescent Psychiatry, Neuroscience & Physiology, and Psychiatry, and the Neuroscience Institute New York University Langone Health, 550 First Ave., New York, NY 10016, United States of America; Center for Dementia Research, The Nathan S. Kline Institute for Psychiatric Research, New York State Office of Mental Health, 140 Old Orangeburg Road, Bldg. 35, Orangeburg, NY 10962, United States of America.
| | - Helen E Scharfman
- Departments of Child & Adolescent Psychiatry, Neuroscience & Physiology, and Psychiatry, and the Neuroscience Institute New York University Langone Health, 550 First Ave., New York, NY 10016, United States of America; Center for Dementia Research, The Nathan S. Kline Institute for Psychiatric Research, New York State Office of Mental Health, 140 Old Orangeburg Road, Bldg. 35, Orangeburg, NY 10962, United States of America
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Lisgaras CP, Scharfman HE. Interictal Spikes in Alzheimer's Disease: Preclinical Evidence for Dominance of the Dentate Gyrus and Cholinergic Control by Medial Septum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.24.537999. [PMID: 37163065 PMCID: PMC10168266 DOI: 10.1101/2023.04.24.537999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
HIGHLIGHTS Interictal spikes (IIS) occur in 3 mouse lines with Alzheimer's disease featuresIIS in all 3 mouse lines were most frequent during rapid eye movement (REM) sleepThe dentate gyrus showed larger IIS and earlier current sources vs. CA1 or cortexChemogenetic silencing of medial septum (MS) cholinergic neurons reduced IIS during REMMS silencing did not change REM latency, duration, number of bouts or theta power. Interictal spikes (IIS) are a common type of abnormal electrical activity in Alzheimer's disease (AD) and preclinical models. The brain regions where IIS are largest are not known but are important because such data would suggest sites that contribute to IIS generation. Because hippocampus and cortex exhibit altered excitability in AD models, we asked which areas dominate the activity during IIS along the cortical-CA1-dentate gyrus (DG) dorso-ventral axis. Because medial septal (MS) cholinergic neurons are overactive when IIS typically occur, we also tested the novel hypothesis that silencing the MS cholinergic neurons selectively would reduce IIS.We used mice that simulate aspects of AD: Tg2576 mice, presenilin 2 (PS2) knockout mice and Ts65Dn mice. To selectively silence MS cholinergic neurons, Tg2576 mice were bred with choline-acetyltransferase (ChAT)-Cre mice and offspring were injected in the MS with AAV encoding inhibitory designer receptors exclusively activated by designer drugs (DREADDs). We recorded local field potentials along the cortical-CA1-DG axis using silicon probes during wakefulness, slow-wave sleep (SWS) and rapid eye movement (REM) sleep.We detected IIS in all transgenic or knockout mice but not age-matched controls. IIS were detectable throughout the cortical-CA1-DG axis and occurred primarily during REM sleep. In all 3 mouse lines, IIS amplitudes were significantly greater in the DG granule cell layer vs. CA1 pyramidal layer or overlying cortex. Current source density analysis showed robust and early current sources in the DG, and additional sources in CA1 and the cortex also. Selective chemogenetic silencing of MS cholinergic neurons significantly reduced IIS rate during REM sleep without affecting the overall duration, number of REM bouts, latency to REM sleep, or theta power during REM. Notably, two control interventions showed no effects.Consistent maximal amplitude and strong current sources of IIS in the DG suggest that the DG is remarkably active during IIS. In addition, selectively reducing MS cholinergic tone, at times when MS is hyperactive, could be a new strategy to reduce IIS in AD.
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Scaduto P, Lauterborn JC, Cox CD, Fracassi A, Zeppillo T, Gutierrez BA, Keene CD, Crane PK, Mukherjee S, Russell WK, Taglialatela G, Limon A. Functional excitatory to inhibitory synaptic imbalance and loss of cognitive performance in people with Alzheimer's disease neuropathologic change. Acta Neuropathol 2023; 145:303-324. [PMID: 36538112 PMCID: PMC9925531 DOI: 10.1007/s00401-022-02526-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 11/12/2022] [Accepted: 11/27/2022] [Indexed: 12/24/2022]
Abstract
Individuals at distinct stages of Alzheimer's disease (AD) show abnormal electroencephalographic activity, which has been linked to network hyperexcitability and cognitive decline. However, whether pro-excitatory changes at the synaptic level are observed in brain areas affected early in AD, and if they are emergent in MCI, is not clearly known. Equally important, it is not known whether global synaptic E/I imbalances correlate with the severity of cognitive impairment in the continuum of AD. Measuring the amplitude of ion currents of human excitatory and inhibitory synaptic receptors microtransplanted from the hippocampus and temporal cortex of cognitively normal, mildly cognitively impaired and AD individuals into surrogate cells, we found regional differences in pro-excitatory shifts of the excitatory to inhibitory (E/I) current ratio that correlates positively with toxic proteins and degree of pathology, and impinges negatively on cognitive performance scores. Using these data with electrophysiologically anchored analysis of the synapto-proteome in the same individuals, we identified a group of proteins sustaining synaptic function and those related to synaptic toxicity. We also found an uncoupling between the function and expression of proteins for GABAergic signaling in the temporal cortex underlying larger E/I and worse cognitive performance. Further analysis of transcriptomic and in situ hybridization datasets from an independent cohort across the continuum of AD confirm regional differences in pro-excitatory shifts of the E/I balance that correlate negatively with the most recent calibrated composite scores for memory, executive function, language and visuospatial abilities, as well as overall cognitive performance. These findings indicate that early shifts of E/I balance may contribute to loss of cognitive capabilities in the continuum of AD clinical syndrome.
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Affiliation(s)
- Pietro Scaduto
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Julie C Lauterborn
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - Conor D Cox
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - Anna Fracassi
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Tommaso Zeppillo
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Berenice A Gutierrez
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - C Dirk Keene
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA, USA
| | - Paul K Crane
- Department of Medicine, University of Washington, Seattle, WA, USA
| | | | - William K Russell
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, USA
| | - Giulio Taglialatela
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Agenor Limon
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch at Galveston, Galveston, TX, USA.
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Early impairments of visually-driven neuronal ensemble dynamics in the rTg4510 tauopathy mouse model. Neurobiol Dis 2023; 178:106012. [PMID: 36696792 DOI: 10.1016/j.nbd.2023.106012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 01/20/2023] [Accepted: 01/21/2023] [Indexed: 01/24/2023] Open
Abstract
Tau protein pathology is a hallmark of many neurodegenerative diseases, including Alzheimer's Disease or frontotemporal dementia. Synaptic dysfunction and abnormal visual evoked potentials have been reported in murine models of tauopathy, but little is known about the state of the network activity on a single neuronal level prior to brain atrophy. In the present study, oscillatory rhythms and single-cell calcium activity of primary visual cortex pyramidal neuron population were investigated in basal and light evoked states in the rTg4510 tauopathy mouse model prior to neurodegeneration. We found a decrease in their responsivity and overall activity which was insensitive to GABAergic modulation. Despite an enhancement of basal state coactivation of cortical pyramidal neurons, a loss of input-output synchronicity was observed. Dysfunction of cortical pyramidal function was also reflected in a reduction of basal theta oscillations and enhanced susceptibility to a sub-convulsive dose of pentylenetetrazol in rTg4510 mice. Our results unveil impairments in visual cortical pyramidal neuron processing and define aberrant oscillations as biomarker candidates in early stages of neurodegenerative tauopathies.
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Ghatak S, Nakamura T, Lipton SA. Aberrant protein S-nitrosylation contributes to hyperexcitability-induced synaptic damage in Alzheimer's disease: Mechanistic insights and potential therapies. Front Neural Circuits 2023; 17:1099467. [PMID: 36817649 PMCID: PMC9932935 DOI: 10.3389/fncir.2023.1099467] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 01/18/2023] [Indexed: 02/05/2023] Open
Abstract
Alzheimer's disease (AD) is arguably the most common cause of dementia in the elderly and is marked by progressive synaptic degeneration, which in turn leads to cognitive decline. Studies in patients and in various AD models have shown that one of the early signatures of AD is neuronal hyperactivity. This excessive electrical activity contributes to dysregulated neural network function and synaptic damage. Mechanistically, evidence suggests that hyperexcitability accelerates production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) that contribute to neural network impairment and synapse loss. This review focuses on the pathways and molecular changes that cause hyperexcitability and how RNS-dependent posttranslational modifications, represented predominantly by protein S-nitrosylation, mediate, at least in part, the deleterious effects of hyperexcitability on single neurons and the neural network, resulting in synaptic loss in AD.
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Affiliation(s)
- Swagata Ghatak
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India
| | - Tomohiro Nakamura
- Neurodegeneration New Medicines Center and Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States,*Correspondence: Tomohiro Nakamura,
| | - Stuart A. Lipton
- Neurodegeneration New Medicines Center and Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States,Department of Neurosciences, School of Medicine, University of California, San Diego, La Jolla, CA, United States,Stuart A. Lipton,
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7
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Mao D, Zheng Y, Xu F, Han X, Zhao H. HMGB1 in nervous system diseases: A common biomarker and potential therapeutic target. Front Neurol 2022; 13:1029891. [PMID: 36388178 PMCID: PMC9659947 DOI: 10.3389/fneur.2022.1029891] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 10/10/2022] [Indexed: 11/29/2022] Open
Abstract
High-mobility group box-1 (HMGB1) is a nuclear protein associated with early inflammatory changes upon extracellular secretion expressed in various cells, including neurons and microglia. With the progress of research, neuroinflammation is believed to be involved in the pathogenesis of neurological diseases such as Parkinson's, epilepsy, and autism. As a key promoter of neuroinflammation, HMGB1 is thought to be involved in the pathogenesis of Parkinson's disease, stroke, traumatic brain injury, epilepsy, autism, depression, multiple sclerosis, and amyotrophic lateral sclerosis. However, in the clinic, HMGB1 has not been described as a biomarker for the above-mentioned diseases. However, the current preclinical research results show that HMGB1 antagonists have positive significance in the treatment of Parkinson's disease, stroke, traumatic brain injury, epilepsy, and other diseases. This review discusses the possible mechanisms by which HMGB1 mediates Parkinson's disease, stroke, traumatic brain injury, epilepsy, autism, depression, multiple sclerosis, amyotrophic lateral sclerosis, and the potential of HMGB1 as a biomarker for these diseases. Future research needs to further explore the underlying molecular mechanisms and clinical translation.
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Affiliation(s)
- Di Mao
- Department of Pediatrics, Jinan Central Hospital, Shandong University, Jinan, China
| | - Yuan Zheng
- Department of Pediatrics, Central Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Fenfen Xu
- Department of Pediatrics, Central Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Xiao Han
- Department of Pediatrics, Central Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Hongyang Zhao
- Department of Pediatrics, Central Hospital Affiliated to Shandong First Medical University, Jinan, China
- *Correspondence: Hongyang Zhao
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Savage SA, Baker J, Milton F, Butler C, Zeman A. Clinical outcomes in Transient Epileptic Amnesia: a 10-year follow-up cohort study of 47 cases. Epilepsia 2022; 63:1115-1129. [PMID: 35253220 PMCID: PMC9310913 DOI: 10.1111/epi.17214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 02/08/2022] [Accepted: 03/03/2022] [Indexed: 11/27/2022]
Abstract
Objective Transient epileptic amnesia (TEA) is a form of adult‐onset epilepsy where presenting features are well described, but little is known regarding prognosis. This study aimed to elucidate the long‐term prognosis of TEA regarding seizure control, memory, medical comorbidities, and life expectancy. Methods Up‐to‐date clinical information was collected for 47 people diagnosed with TEA who had joined the The Impairment of Memory in Epilepsy (TIME) study 10 years earlier. At entry to the study, information about comorbid conditions was systematically collected. Details regarding subsequent diagnoses, seizure activity, changes to treatment, or reports of cognitive impairment were obtained through the family doctor. The variables of interest were compared with UK population data. Results Mortality in the cohort was 21 of 47 (45%), with an average age at death of 82.5 years. Seizures remained well controlled for the majority but medications required adjustments in dose and type for some (28%). A small number (three cases) remained seizure‐free without medication. History of cardiovascular disorders was frequent (78.7%), typically involving hypertension (55.3%). Autoimmune disorders (25.5%), cancer (23.4%), and depression (21.3%) were also commonly reported. Although persisting memory problems were often noted, dementia was diagnosed in seven cases (14.9%). Life expectancy and comorbidities in TEA did not differ from available population norms. Significance Results suggest that life expectancy is not reduced in TEA. Although TEA does not appear to be a self‐limiting form of epilepsy, seizures are typically well controlled via medication. Because adjustments to medication may be required, even after long periods of stability, ongoing medical monitoring is recommended. Comorbid vascular disorders are frequent but appear similar to general population estimates. Monitoring mood may be important, given that people with chronic conditions are often vulnerable to depression. Because of persisting memory difficulties, the development of effective memory interventions for people with TEA is warranted.
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Affiliation(s)
- Sharon A Savage
- Cognitive & Behavioural Neurology, University of Exeter Medical School, College House, St Luke's Campus, Exeter, EX1 2LU, UK.,School of Psychological Sciences, University of Newcastle, Callaghan, New South Wales, 2308, Australia
| | - John Baker
- Cognitive & Behavioural Neurology, University of Exeter Medical School, College House, St Luke's Campus, Exeter, EX1 2LU, UK.,Dementia Research Centre, UCL Queen Square institute of Neurology, London, WC1N 3BG, UK
| | - Fraser Milton
- Discipline of Psychology, University of Exeter, Washington Singer Laboratories, Exeter, EX4 4QG, UK
| | - Chris Butler
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, UK.,Department of Brain Sciences, Imperial College, London, W12 0NN, UK
| | - Adam Zeman
- Cognitive & Behavioural Neurology, University of Exeter Medical School, College House, St Luke's Campus, Exeter, EX1 2LU, UK
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Epileptic Mechanisms Shared by Alzheimer's Disease: Viewed via the Unique Lens of Genetic Epilepsy. Int J Mol Sci 2021; 22:ijms22137133. [PMID: 34281185 PMCID: PMC8268161 DOI: 10.3390/ijms22137133] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/14/2021] [Accepted: 06/15/2021] [Indexed: 12/18/2022] Open
Abstract
Our recent work on genetic epilepsy (GE) has identified common mechanisms between GE and neurodegenerative diseases including Alzheimer's disease (AD). Although both disorders are seemingly unrelated and occur at opposite ends of the age spectrum, it is likely there are shared mechanisms and studies on GE could provide unique insights into AD pathogenesis. Neurodegenerative diseases are typically late-onset disorders, but the underlying pathology may have already occurred long before the clinical symptoms emerge. Pathophysiology in the early phase of these diseases is understudied but critical for developing mechanism-based treatment. In AD, increased seizure susceptibility and silent epileptiform activity due to disrupted excitatory/inhibitory (E/I) balance has been identified much earlier than cognition deficit. Increased epileptiform activity is likely a main pathology in the early phase that directly contributes to impaired cognition. It is an enormous challenge to model the early phase of pathology with conventional AD mouse models due to the chronic disease course, let alone the complex interplay between subclinical nonconvulsive epileptiform activity, AD pathology, and cognition deficit. We have extensively studied GE, especially with gene mutations that affect the GABA pathway such as mutations in GABAA receptors and GABA transporter 1. We believe that some mouse models developed for studying GE and insights gained from GE could provide unique opportunity to understand AD. These include the pathology in early phase of AD, endoplasmic reticulum (ER) stress, and E/I imbalance as well as the contribution to cognitive deficit. In this review, we will focus on the overlapping mechanisms between GE and AD, the insights from mutations affecting GABAA receptors, and GABA transporter 1. We will detail mechanisms of E/I imbalance and the toxic epileptiform generation in AD, and the complex interplay between ER stress, impaired membrane protein trafficking, and synaptic physiology in both GE and AD.
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10
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Neuronal Network Excitability in Alzheimer's Disease: The Puzzle of Similar versus Divergent Roles of Amyloid β and Tau. eNeuro 2021; 8:ENEURO.0418-20.2020. [PMID: 33741601 PMCID: PMC8174042 DOI: 10.1523/eneuro.0418-20.2020] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 12/02/2020] [Accepted: 12/18/2020] [Indexed: 12/12/2022] Open
Abstract
Alzheimer’s disease (AD) is the most frequent neurodegenerative disorder that commonly causes dementia in the elderly. Recent evidence indicates that network abnormalities, including hypersynchrony, altered oscillatory rhythmic activity, interneuron dysfunction, and synaptic depression, may be key mediators of cognitive decline in AD. In this review, we discuss characteristics of neuronal network excitability in AD, and the role of Aβ and tau in the induction of network hyperexcitability. Many patients harboring genetic mutations that lead to increased Aβ production suffer from seizures and epilepsy before the development of plaques. Similarly, pathologic accumulation of hyperphosphorylated tau has been associated with hyperexcitability in the hippocampus. We present common and divergent roles of tau and Aβ on neuronal hyperexcitability in AD, and hypotheses that could serve as a template for future experiments.
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Petrisko TJ, Bloemer J, Pinky PD, Srinivas S, Heslin RT, Du Y, Setti SE, Hong H, Suppiramaniam V, Konat GW, Reed MN. Neuronal CXCL10/CXCR3 Axis Mediates the Induction of Cerebral Hyperexcitability by Peripheral Viral Challenge. Front Neurosci 2020; 14:220. [PMID: 32265633 PMCID: PMC7105801 DOI: 10.3389/fnins.2020.00220] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 02/28/2020] [Indexed: 12/20/2022] Open
Abstract
Peripheral infections can potently exacerbate neuropathological conditions, though the underlying mechanisms are poorly understood. We have previously demonstrated that intraperitoneal (i.p.) injection of a viral mimetic, polyinosinic-polycytidylic acid (PIC) induces a robust generation of CXCL10 chemokine in the hippocampus. The hippocampus also features hyperexcitability of neuronal circuits following PIC challenge. The present study was undertaken to determine the role of CXCL10 in mediating the development of hyperexcitability in response to PIC challenge. Briefly, young female C57BL/6 mice were i.p. injected with PIC, and after 24 h, the brains were analyzed by confocal microscopy. CXCL10 staining of neuronal perikarya and a less intense staining of the neuropil was observed in the hippocampus and cortex. CXCL10 staining was also evident in a subpopulation of astrocytes, whereas microglia were CXCL10 negative. CXCR3, the cognate receptor of CXCL10 was present exclusively on neurons, indicating that the CXCL10/CXCR3 axis operates through an autocrine/paracrine neuronal signaling. Blocking cerebral CXCR3 through intracerebroventricular injection of a specific inhibitor, AMG487, abrogated PIC challenge-induced increase in basal synaptic transmission and long-term potentiation (LTP), as well as the reduction of paired-pulse facilitation (PPF), in the hippocampus. The PIC-mediated abolishment of hippocampal long-term depression (LTD) was also restored after administration of AMG487. Moreover, CXCR3 inhibition attenuated seizure hypersensitivity induced by PIC challenge. The efficacy of AMG487 strongly strengthens the notion that CXCL10/CXCR3 axis mediates the induction of cerebral hyperexcitability by PIC challenge.
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Affiliation(s)
- Tiffany J Petrisko
- Departments of Biochemistry and Neuroscience, West Virginia University School of Medicine, Morgantown, WV, United States
| | - Jenna Bloemer
- Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, United States
| | - Priyanka D Pinky
- Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, United States
| | - Sriraja Srinivas
- Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, United States
| | - Ryan T Heslin
- Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, United States
| | - Yifeng Du
- Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, United States
| | - Sharay E Setti
- Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, United States
| | - Hao Hong
- Department of Pharmacy, The First Affiliated Hospital of Xiamen University, Xiamen, China.,Key Laboratory of Neuropsychiatric Diseases, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Vishnu Suppiramaniam
- Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, United States.,Center for Neuroscience Initiative, Auburn University, Auburn, AL, United States
| | - Gregory W Konat
- Departments of Biochemistry and Neuroscience, West Virginia University School of Medicine, Morgantown, WV, United States
| | - Miranda N Reed
- Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, United States.,Center for Neuroscience Initiative, Auburn University, Auburn, AL, United States
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12
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Paudel YN, Angelopoulou E, Jones NC, O’Brien TJ, Kwan P, Piperi C, Othman I, Shaikh MF. Tau Related Pathways as a Connecting Link between Epilepsy and Alzheimer's Disease. ACS Chem Neurosci 2019; 10:4199-4212. [PMID: 31532186 DOI: 10.1021/acschemneuro.9b00460] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Emerging findings point toward an important interconnection between epilepsy and Alzheimer's disease (AD) pathogenesis. Patients with epilepsy (PWE) commonly exhibit cognitive impairment similar to AD patients, who in turn are at a higher risk of developing epilepsy compared to age-matched controls. To date, no disease-modifying treatment strategy is available for either epilepsy or AD, reflecting an immediate need for exploring common molecular targets, which can delineate a possible mechanistic link between epilepsy and AD. This review attempts to disentangle the interconnectivity between epilepsy and AD pathogenesis via the crucial contribution of Tau protein. Tau protein is a microtubule-associated protein (MAP) that has been implicated in the pathophysiology of both epilepsy and AD. Hyperphosphorylation of Tau contributes to the different forms of human epilepsy and inhibition of the same exerted seizure inhibitions and altered disease progression in a range of animal models. Moreover, Tau-protein-mediated therapy has demonstrated promising outcomes in experimental models of AD. In this review, we discuss how Tau-related mechanisms might present a link between the cause of seizures in epilepsy and cognitive disruption in AD. Untangling this interconnection might be instrumental in designing novel therapies that can minimize epileptic seizures and cognitive deficits in patients with epilepsy and AD.
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Affiliation(s)
- Yam Nath Paudel
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor 46150, Malaysia
| | - Efthalia Angelopoulou
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, Athens 10679, Greece
| | - Nigel C. Jones
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne 3800, Australia
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, Parkville, Victoria 3010, Australia
| | - Terence J. O’Brien
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne 3800, Australia
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, Parkville, Victoria 3010, Australia
| | - Patrick Kwan
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne 3800, Australia
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, Parkville, Victoria 3010, Australia
| | - Christina Piperi
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, Athens 10679, Greece
| | - Iekhsan Othman
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor 46150, Malaysia
| | - Mohd. Farooq Shaikh
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor 46150, Malaysia
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne 3800, Australia
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Zhou X, Tao H, Cai Y, Cui L, Zhao B, Li K. Stage-dependent involvement of ADAM10 and its significance in epileptic seizures. J Cell Mol Med 2019; 23:4494-4504. [PMID: 31087543 PMCID: PMC6584734 DOI: 10.1111/jcmm.14307] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 01/05/2019] [Accepted: 03/11/2019] [Indexed: 12/22/2022] Open
Abstract
The prevalence of epileptic seizures in Alzheimer's disease (AD) has attracted an increasing amount of attention in recent years, and many cohort studies have found several risk factors associated with the genesis of seizures in AD. Among these factors, young age and severe dementia are seemingly contradictory and independent risk factors, indicating that the pathogenesis of epileptic seizures is, to a certain extent, stage‐dependent. A disintegrin and metalloproteinase domain‐containing protein 10 (ADAM10) is a crucial α‐secretase responsible for ectodomain shedding of its substrates; thus, the function of this protein depends on the biological effects of its substrates. Intriguingly, transgenic models have demonstrated ADAM10 to be associated with epilepsy. Based on the biological effects of its substrates, the potential pathogenic roles of ADAM10 in epileptic seizures can be classified into amyloidogenic processes in the ageing stage and cortical dysplasia in the developmental stage. Therefore, ADAM10 is reviewed here as a stage‐dependent modulator in the pathogenesis of epilepsy. Current data regarding ADAM10 in epileptic seizures were collected and reviewed for potential pathogenic roles (ie amyloidogenic processes and cortical dysplasia) and regulatory mechanisms (ie transcriptional and posttranscriptional regulation). These findings are then discussed in terms of the significance of the stage‐dependent functions of ADAM10 in epilepsy. Several potential targets for seizure control, such as candidate transcription factors and microRNAs that regulate ADAM10, as well as potential genetic screening tools for the early recognition of cortical dysplasia, have been suggested but must be studied in more detail.
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Affiliation(s)
- Xu Zhou
- Clinical Research Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Hua Tao
- Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China.,Guangdong Key Laboratory of Age-related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Yujie Cai
- Institute of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Lili Cui
- Institute of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Bin Zhao
- Guangdong Key Laboratory of Age-related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China.,Institute of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Keshen Li
- Institute of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China.,Stroke Center, Neurology & Neurosurgery Division, Clinical Medicine Research Institute & the First Affiliated Hospital, Jinan University, Guangzhou, China
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14
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Novel Quantitative Analyses of Spontaneous Synaptic Events in Cortical Pyramidal Cells Reveal Subtle Parvalbumin-Expressing Interneuron Dysfunction in a Knock-In Mouse Model of Alzheimer's Disease. eNeuro 2018; 5:eN-CFN-0059-18. [PMID: 30105300 PMCID: PMC6088364 DOI: 10.1523/eneuro.0059-18.2018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 06/19/2018] [Accepted: 06/24/2018] [Indexed: 12/19/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder that has become a compelling global public health concern. Besides pathological hallmarks such as extracellular amyloid plaques, intracellular neurofibrillary tangles (NFTs), and loss of neurons and synapses, clinical reports have shown that epileptiform activity, even seizures, can occur early in the disease. Aberrant synaptic and network activities as well as epileptiform discharges have also been observed in various mouse models of AD. The new AppNL-F mouse model is generated by a gene knock-in approach and there are limited studies on basic synaptic properties in AppNL-F mice. Therefore, we applied quantitative methods to analyze spontaneous excitatory and inhibitory synaptic events in parietal cortex layer 2/3 pyramidal cells. First, by an objective amplitude distribution analysis, we found decreased amplitudes of spontaneous IPSCs (sIPSCs) in aged AppNL-F mice caused by a reduction in the amplitudes of the large sIPSCs with fast rates of rise, consistent with deficits in the function of parvalbumin-expressing interneurons (PV INs). Second, we calculated the burstiness and memory in a series of successive synaptic events. Lastly, by using a novel approach to determine the excitation-to-inhibition (E/I) ratio, we found no changes in the AppNL-F mice, indicating that homeostatic mechanisms may have maintained the overall balance of excitation and inhibition in spite of a mildly impaired PV IN function.
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15
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DiFrancesco JC, Tremolizzo L, Polonia V, Giussani G, Bianchi E, Franchi C, Nobili A, Appollonio I, Beghi E, Ferrarese C. Adult-Onset Epilepsy in Presymptomatic Alzheimer's Disease: A Retrospective Study. J Alzheimers Dis 2018; 60:1267-1274. [PMID: 28968234 DOI: 10.3233/jad-170392] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND The prevalence of epilepsy with onset in adulthood increases with age, mainly due to the accumulation of brain damage. However, a significant proportion of patients experience seizures of unknown cause. Alzheimer's disease (AD) is associated with an increased risk of seizures. Seizure activity is interpreted as a secondary event related to hyperexcitability caused by amyloid-β aggregation. OBJECTIVE Since neurodegenerative processes begin several years before clinical symptoms, epilepsy could be more frequent in the presymptomatic stages of dementia. METHODS We retrospectively reviewed the prevalence of epilepsy of unknown origin with adult onset before cognitive decline in a large cohort of AD patients (EPS-AD) recruited based on clinical and neuropsychological data. Data of patients with epilepsy followed by AD were compared with two control groups: patients with AD without seizures (no EPS-AD) and a large reference population (RP). RESULTS In AD patients, the prevalence of epilepsy of unknown origin, with onset in the adulthood before cognitive decline is 17.1 times higher compared with the RP (95% CI: 10.3-28.3). In EPS-AD, seizures begin on average 4.6 years (median 2.0) before the onset of cognitive symptoms and cognitive decline starts 3.6 years earlier compared with noEPS-AD. CONCLUSIONS Neurodegenerative processes of dementia could play a key role in the pathogenesis of epilepsy in a subgroup of individuals intended to develop cognitive decline. Adult-onset epilepsy of undefined cause could thus represent a risk factor for the ongoing neurodegenerative damage, even preceding by years the onset of clinical symptoms of dementia.
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Affiliation(s)
- Jacopo C DiFrancesco
- Department of Neurology, San Gerardo Hospital, Monza, Italy.,School of Medicine and Surgery and Milan Center for Neuroscience (NeuroMi), University of Milano-Bicocca, Monza, Italy
| | - Lucio Tremolizzo
- Department of Neurology, San Gerardo Hospital, Monza, Italy.,School of Medicine and Surgery and Milan Center for Neuroscience (NeuroMi), University of Milano-Bicocca, Monza, Italy
| | - Valeria Polonia
- School of Medicine and Surgery and Milan Center for Neuroscience (NeuroMi), University of Milano-Bicocca, Monza, Italy
| | - Giorgia Giussani
- Department of Neuroscience, IRCCS-Institute for Pharmacological Research "Mario Negri", Milan, Italy
| | - Elisa Bianchi
- Department of Neuroscience, IRCCS-Institute for Pharmacological Research "Mario Negri", Milan, Italy
| | - Carlotta Franchi
- Department of Neuroscience, IRCCS-Institute for Pharmacological Research "Mario Negri", Milan, Italy
| | - Alessandro Nobili
- Department of Neuroscience, IRCCS-Institute for Pharmacological Research "Mario Negri", Milan, Italy
| | - Ildebrando Appollonio
- Department of Neurology, San Gerardo Hospital, Monza, Italy.,School of Medicine and Surgery and Milan Center for Neuroscience (NeuroMi), University of Milano-Bicocca, Monza, Italy
| | - Ettore Beghi
- Department of Neuroscience, IRCCS-Institute for Pharmacological Research "Mario Negri", Milan, Italy
| | - Carlo Ferrarese
- Department of Neurology, San Gerardo Hospital, Monza, Italy.,School of Medicine and Surgery and Milan Center for Neuroscience (NeuroMi), University of Milano-Bicocca, Monza, Italy
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16
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Kodam A, Ourdev D, Maulik M, Hariharakrishnan J, Banerjee M, Wang Y, Kar S. A role for astrocyte-derived amyloid β peptides in the degeneration of neurons in an animal model of temporal lobe epilepsy. Brain Pathol 2018; 29:28-44. [PMID: 29665128 DOI: 10.1111/bpa.12617] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 04/11/2018] [Indexed: 12/13/2022] Open
Abstract
Kainic acid, an analogue of the excitatory neurotransmitter glutamate, can trigger seizures and neurotoxicity in the hippocampus and other limbic structures in a manner that mirrors the neuropathology of human temporal lobe epilepsy (TLE). However, the underlying mechanisms associated with the neurotoxicity remain unclear. Since amyloid-β (Aβ) peptides, which are critical in the development of Alzheimer's disease, can mediate toxicity by activating glutamatergic NMDA receptors, it is likely that the enhanced glutamatergic transmission that renders hippocampal neurons vulnerable to kainic acid treatment may involve Aβ peptides. Thus, we seek to establish what role Aβ plays in kainic acid-induced toxicity using in vivo and in vitro paradigms. Our results show that systemic injection of kainic acid to adult rats triggers seizures, gliosis and loss of hippocampal neurons, along with increased levels/processing of amyloid precursor protein (APP), resulting in the enhanced production of Aβ-related peptides. The changes in APP levels/processing were evident primarily in activated astrocytes, implying a role for astrocytic Aβ in kainic acid-induced toxicity. Accordingly, we showed that treating rat primary cultured astrocytes with kainic acid can lead to increased Aβ production/secretion without any compromise in cell viability. Additionally, we revealed that kainic acid reduces neuronal viability more in neuronal/astrocyte co-cultures than in pure neuronal culture, and this is attenuated by precluding Aβ production. Collectively, these results indicate that increased production/secretion of Aβ-related peptides from activated astrocytes can contribute to neurotoxicity in kainic acid-treated rats. Since kainic acid administration can lead to neuropathological changes resembling TLE, it is likely that APP/Aβ peptides derived from astrocytes may have a role in TLE pathogenesis.
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Affiliation(s)
- A Kodam
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - D Ourdev
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - M Maulik
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - J Hariharakrishnan
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - M Banerjee
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - Y Wang
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - S Kar
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8.,Department of Medicine, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
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17
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Scharfman HE, Kanner AM, Friedman A, Blümcke I, Crocker CE, Cendes F, Diaz-Arrastia R, Förstl H, Fenton AA, Grace AA, Palop J, Morrison J, Nehlig A, Prasad A, Wilcox KS, Jette N, Pohlmann-Eden B. Epilepsy as a Network Disorder (2): What can we learn from other network disorders such as dementia and schizophrenia, and what are the implications for translational research? Epilepsy Behav 2018; 78:302-312. [PMID: 29097123 PMCID: PMC5756681 DOI: 10.1016/j.yebeh.2017.09.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 09/18/2017] [Accepted: 09/18/2017] [Indexed: 12/18/2022]
Abstract
There is common agreement that many disorders of the central nervous system are 'complex', that is, there are many potential factors that influence the development of the disease, underlying mechanisms, and successful treatment. Most of these disorders, unfortunately, have no cure at the present time, and therapeutic strategies often have debilitating side effects. Interestingly, some of the 'complexities' of one disorder are found in another, and the similarities are often network defects. It seems likely that more discussions of these commonalities could advance our understanding and, therefore, have clinical implications or translational impact. With this in mind, the Fourth International Halifax Epilepsy Conference and Retreat was held as described in the prior paper, and this companion paper focuses on the second half of the meeting. Leaders in various subspecialties of epilepsy research were asked to address aging and dementia or psychosis in people with epilepsy (PWE). Commonalities between autism, depression, aging and dementia, psychosis, and epilepsy were the focus of the presentations and discussion. In the last session, additional experts commented on new conceptualization of translational epilepsy research efforts. Here, the presentations are reviewed, and salient points are highlighted.
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Affiliation(s)
- Helen E Scharfman
- Departments of Psychiatry, Neurosciences and Physiology, and the Neuroscience Institute, New York University Langone Medical Center, New York, NY 10016, USA.
| | - Andres M Kanner
- University of Miami, Miller School of Medicine, 1120 NW 14th Street, Room #1324, Miami, FL 33136, USA
| | - Alon Friedman
- Department of Medical Neuroscience, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada; Department of Pediatrics, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada; Department of Physiology and Cell Biology, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ingmar Blümcke
- Neuropathological Institute, University Hospitals Erlangen, Germany
| | - Candice E Crocker
- Nova Scotia Early Psychosis Program, Department of Psychiatry, Dalhousie University, Halifax, NS, Canada
| | - Fernando Cendes
- Department of Neurology, University of Campinas, 13083-888 Campinas, Sao Paulo, Brazil
| | - Ramon Diaz-Arrastia
- Centre for Neuroscience & Regenerative Medicine, Uniformed Services University of the Health Sciences, 12725 Twinbrook Parkway, Rockville, MD 20852, USA
| | - Hans Förstl
- Department of Psychiatry, University of Munich, Klinikum rechts der Isar, Ismaninger Strabe 22, D-81675 Munich, Germany
| | - André A Fenton
- Centre for Neural Science, New York University, 4 Washington Place, Room 809, New York, NY 10003, USA
| | - Anthony A Grace
- University of Pittsburgh, 456 Langley Hall, 4200 Fifth Avenue, Pittsburgh, PA 15269, USA
| | - Jorge Palop
- Department of Neurology, Gladstone Institute, 1650 Owens Street, San Francisco, CA 94158-2261, USA
| | - Jason Morrison
- Department of Psychiatry, Dalhousie University, Halifax, NS, Canada
| | - Astrid Nehlig
- INSERM U 1129, Hôpital Necker, Paris, Faculty of Medicine, Strasbourg, France
| | - Asuri Prasad
- Department of Pediatrics, Children's Hospital of Western Ontario, London, ON, Canada
| | - Karen S Wilcox
- Department of Pharmacology & Toxicology, Anticonvulsant Drug Development Program, University of Utah, Salt Lake City, UT, USA
| | - Nathalie Jette
- Icahn School of Medicine at Mount Sinai, Department of Neurology, New York, NY, USA; Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - Bernd Pohlmann-Eden
- Brain Repair Center, Life Science Research Institute, Dalhousie University, Room 229, PO Box 15000, Halifax, NS B3H4R2, Canada.
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18
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Kazim SF, Chuang SC, Zhao W, Wong RKS, Bianchi R, Iqbal K. Early-Onset Network Hyperexcitability in Presymptomatic Alzheimer's Disease Transgenic Mice Is Suppressed by Passive Immunization with Anti-Human APP/Aβ Antibody and by mGluR5 Blockade. Front Aging Neurosci 2017; 9:71. [PMID: 28392767 PMCID: PMC5364175 DOI: 10.3389/fnagi.2017.00071] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 03/08/2017] [Indexed: 11/26/2022] Open
Abstract
Cortical and hippocampal network hyperexcitability appears to be an early event in Alzheimer’s disease (AD) pathogenesis, and may contribute to memory impairment. It remains unclear if network hyperexcitability precedes memory impairment in mouse models of AD and what are the underlying cellular mechanisms. We thus evaluated seizure susceptibility and hippocampal network hyperexcitability at ~3 weeks of age [prior to amyloid beta (Aβ) plaque deposition, neurofibrillary pathology, and cognitive impairment] in a triple transgenic mouse model of familial AD (3xTg-AD mouse) that harbors mutated human Aβ precursor protein (APP), tau and presenilin 1 (PS1) genes. Audiogenic seizures were elicited in a higher proportion of 3xTg-AD mice compared with wild type (WT) controls. Seizure susceptibility in 3xTg-AD mice was attenuated either by passive immunization with anti-human APP/Aβ antibody (6E10) or by blockade of metabotropic glutamate receptor 5 (mGluR5) with the selective antagonist, 2-methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP). In in vitro hippocampal slices, suppression of synaptic inhibition with the GABAA receptor antagonist, bicuculline, induced prolonged epileptiform (>1.5 s in duration) ictal-like discharges in the CA3 neuronal network in the majority of the slices from 3xTg-AD mice. In contrast, only short epileptiform (<1.5 s in duration) interictal-like discharges were observed following bicuculline application in the CA3 region of WT slices. The ictal-like activity in CA3 region of the hippocampus was significantly reduced in the 6E10-immunized compared to the saline-treated 3xTg-AD mice. MPEP acutely suppressed the ictal-like discharges in 3xTg-AD slices. Remarkably, epileptiform discharge duration positively correlated with intraneuronal human (transgenic) APP/Aβ expression in the CA3 region of the hippocampus. Our data suggest that in a mouse model of familial AD, hypersynchronous network activity underlying seizure susceptibility precedes Aβ plaque pathology and memory impairment. This early-onset network hyperexcitability can be suppressed by passive immunization with an anti-human APP/Aβ antibody and by mGluR5 blockade in 3xTg-AD mice.
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Affiliation(s)
- Syed F Kazim
- Robert F. Furchgott Center for Neural and Behavioral Science and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical CenterBrooklyn, NY, USA; Department of Neurochemistry and SUNY Downstate/NYSIBR Center for Developmental Neuroscience, New York State Institute for Basic Research (NYSIBR)Staten Island, NY, USA; Graduate Program in Neural and Behavioral Science, SUNY Downstate Medical CenterBrooklyn, NY, USA
| | - Shih-Chieh Chuang
- Robert F. Furchgott Center for Neural and Behavioral Science and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center Brooklyn, NY, USA
| | - Wangfa Zhao
- Robert F. Furchgott Center for Neural and Behavioral Science and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center Brooklyn, NY, USA
| | - Robert K S Wong
- Robert F. Furchgott Center for Neural and Behavioral Science and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center Brooklyn, NY, USA
| | - Riccardo Bianchi
- Robert F. Furchgott Center for Neural and Behavioral Science and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center Brooklyn, NY, USA
| | - Khalid Iqbal
- Department of Neurochemistry and SUNY Downstate/NYSIBR Center for Developmental Neuroscience, New York State Institute for Basic Research (NYSIBR) Staten Island, NY, USA
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Aller-Alvarez J, Menéndez-González M, Ribacoba-Montero R, Salvado M, Vega V, Suárez-Moro R, Sueiras M, Toledo M, Salas-Puig J, Álvarez-Sabin J. Myoclonic epilepsy in Down syndrome and Alzheimer disease. NEUROLOGÍA (ENGLISH EDITION) 2017. [DOI: 10.1016/j.nrleng.2014.12.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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20
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Aller-Alvarez J, Menéndez-González M, Ribacoba-Montero R, Salvado M, Vega V, Suárez-Moro R, Sueiras M, Toledo M, Salas-Puig J, Álvarez-Sabin J. Epilepsia mioclónica en el síndrome de Down y en la enfermedad de Alzheimer. Neurologia 2017; 32:69-73. [DOI: 10.1016/j.nrl.2014.12.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 12/09/2014] [Accepted: 12/11/2014] [Indexed: 10/24/2022] Open
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21
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Rodríguez-Martínez D, Martínez-Losa MM, Alvarez-Dolado M. Cryopreservation of GABAergic Neuronal Precursors for Cell-Based Therapy. PLoS One 2017; 12:e0170776. [PMID: 28122047 PMCID: PMC5266290 DOI: 10.1371/journal.pone.0170776] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 01/10/2017] [Indexed: 12/04/2022] Open
Abstract
Cryopreservation protocols are essential for stem cells storage in order to apply them in the clinic. Here we describe a new standardized cryopreservation protocol for GABAergic neural precursors derived from the medial glanglionic eminence (MGE), a promising source of GABAergic neuronal progenitors for cell therapy against interneuron-related pathologies. We used 10% Me2SO as cryoprotectant and assessed the effects of cell culture amplification and cellular organization, as in toto explants, neurospheres, or individualized cells, on post-thaw cell viability and retrieval. We confirmed that in toto cryopreservation of MGE explants is an optimal preservation system to keep intact the interneuron precursor properties for cell transplantation, together with a high cell viability (>80%) and yield (>70%). Post-thaw proliferation and self-renewal of the cryopreserved precursors were tested in vitro. In addition, their migration capacity, acquisition of mature neuronal morphology, and potency to differentiate into multiple interneuron subtypes were also confirmed in vivo after transplantation. The results show that the cryopreserved precursor features remained intact and were similar to those immediately transplanted after their dissection from the MGE. We hope this protocol will facilitate the generation of biobanks to obtain a permanent and reliable source of GABAergic precursors for clinical application in cell-based therapies against interneuronopathies.
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Affiliation(s)
- Daniel Rodríguez-Martínez
- Laboratory of Cell-based Therapy for Neuropathologies, Andalusian Center for Molecular Biology and Regenerative Medicine (CABIMER), CSIC, Seville, Spain
| | - María Magdalena Martínez-Losa
- Laboratory of Cell-based Therapy for Neuropathologies, Andalusian Center for Molecular Biology and Regenerative Medicine (CABIMER), CSIC, Seville, Spain
| | - Manuel Alvarez-Dolado
- Laboratory of Cell-based Therapy for Neuropathologies, Andalusian Center for Molecular Biology and Regenerative Medicine (CABIMER), CSIC, Seville, Spain
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22
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23
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Amyloid-β effects on synapses and memory require AMPA receptor subunit GluA3. Proc Natl Acad Sci U S A 2016; 113:E6526-E6534. [PMID: 27708157 DOI: 10.1073/pnas.1614249113] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Amyloid-β (Aβ) is a prime suspect for causing cognitive deficits during the early phases of Alzheimer's disease (AD). Experiments in AD mouse models have shown that soluble oligomeric clusters of Aβ degrade synapses and impair memory formation. We show that all Aβ-driven effects measured in these mice depend on AMPA receptor (AMPAR) subunit GluA3. Hippocampal neurons that lack GluA3 were resistant against Aβ-mediated synaptic depression and spine loss. In addition, Aβ oligomers blocked long-term synaptic potentiation only in neurons that expressed GluA3. Furthermore, although Aβ-overproducing mice showed significant memory impairment, memories in GluA3-deficient congenics remained unaffected. These experiments indicate that the presence of GluA3-containing AMPARs is critical for Aβ-mediated synaptic and cognitive deficits.
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24
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Sadek B, Saad A, Sadeq A, Jalal F, Stark H. Histamine H3 receptor as a potential target for cognitive symptoms in neuropsychiatric diseases. Behav Brain Res 2016; 312:415-30. [PMID: 27363923 DOI: 10.1016/j.bbr.2016.06.051] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 06/22/2016] [Accepted: 06/26/2016] [Indexed: 01/27/2023]
Abstract
The potential contributions of the brain histaminergic system in neurodegenerative diseases, and the possiblity of histamine-targeting treatments is attracting considerable interests. The histamine H3 receptor (H3R) is expressed mainly in the central nervous system, and is, consequently, an attractive pharmacological target. Although recently described clinical trials have been disappointing in attention deficit hyperactivity disorder (ADHD) and schizophrenia (SCH), numerous H3R antagonists, including pitolisant, demonstrate potential in the treatment of narcolepsy, excessive daytime sleepiness associated with cognitive impairment, epilepsy, and Alzheimer's disease (AD). This review focuses on the recent preclinical as well as clinical results that support the relevance of H3R antagonists for the treatment of cognitive symptoms in neuropsychiatric diseases, namely AD, epilepsy and SCH. The review summarizes the role of histaminergic neurotransmission with focus on these brain disorders, as well as the effects of numerous H3R antagonists on animal models and humans.
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Affiliation(s)
- Bassem Sadek
- Department of Pharmacology & Therapeutics, College of Medicine & Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain, United Arab Emirates.
| | - Ali Saad
- Department of Pharmacology & Therapeutics, College of Medicine & Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain, United Arab Emirates
| | - Adel Sadeq
- College of Pharmacy, Al Ain University of Science and Technology, Al Ain, United Arab Emirates
| | - Fakhreya Jalal
- Department of Pharmacology & Therapeutics, College of Medicine & Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain, United Arab Emirates
| | - Holger Stark
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University, Universitaetsstr. 1, 40225 Düsseldorf, Germany
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Kam K, Duffy ÁM, Moretto J, LaFrancois JJ, Scharfman HE. Interictal spikes during sleep are an early defect in the Tg2576 mouse model of β-amyloid neuropathology. Sci Rep 2016; 6:20119. [PMID: 26818394 PMCID: PMC4730189 DOI: 10.1038/srep20119] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 12/21/2015] [Indexed: 01/25/2023] Open
Abstract
It has been suggested that neuronal hyperexcitability contributes to Alzheimer's disease (AD), so we asked how hyperexcitability develops in a common mouse model of β-amyloid neuropathology - Tg2576 mice. Using video-EEG recordings, we found synchronized, large amplitude potentials resembling interictal spikes (IIS) in epilepsy at just 5 weeks of age, long before memory impairments or β-amyloid deposition. Seizures were not detected, but they did occur later in life, suggesting that IIS are possibly the earliest stage of hyperexcitability. Interestingly, IIS primarily occurred during rapid-eye movement (REM) sleep, which is notable because REM is associated with increased cholinergic tone and cholinergic impairments are implicated in AD. Although previous studies suggest that cholinergic antagonists would worsen pathophysiology, the muscarinic antagonist atropine reduced IIS frequency. In addition, we found IIS occurred in APP51 mice which overexpress wild type (WT)-APP, although not as uniformly or as early in life as Tg2576 mice. Taken together with results from prior studies, the data suggest that surprising and multiple mechanisms contribute to hyperexcitability. The data also suggest that IIS may be a biomarker for early detection of AD.
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Affiliation(s)
- Korey Kam
- The Nathan Kline Institute for Psychiatric Research Center for Dementia Research Orangeburg, NY 10962, USA.,Graduate Program in Physiology and Neuroscience New York University Langone Medical Center New York, NY 10016, USA
| | - Áine M Duffy
- The Nathan Kline Institute for Psychiatric Research Center for Dementia Research Orangeburg, NY 10962, USA.,Department of Physiology and Neuroscience New York University Langone Medical Center New York, NY 10016, USA
| | - Jillian Moretto
- The Nathan Kline Institute for Psychiatric Research Center for Dementia Research Orangeburg, NY 10962, USA
| | - John J LaFrancois
- The Nathan Kline Institute for Psychiatric Research Center for Dementia Research Orangeburg, NY 10962, USA
| | - Helen E Scharfman
- The Nathan Kline Institute for Psychiatric Research Center for Dementia Research Orangeburg, NY 10962, USA.,Department of Physiology and Neuroscience New York University Langone Medical Center New York, NY 10016, USA.,Department of Child and Adolescent Psychiatry and Psychiatry New York University Langone Medical Center New York, NY 10016, USA
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26
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Jackson HM, Onos KD, Pepper KW, Graham LC, Akeson EC, Byers C, Reinholdt LG, Frankel WN, Howell GR. DBA/2J genetic background exacerbates spontaneous lethal seizures but lessens amyloid deposition in a mouse model of Alzheimer's disease. PLoS One 2015; 10:e0125897. [PMID: 25933409 PMCID: PMC4416920 DOI: 10.1371/journal.pone.0125897] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 03/24/2015] [Indexed: 11/23/2022] Open
Abstract
Alzheimer’s disease (AD) is a leading cause of dementia in the elderly and is characterized by amyloid plaques, neurofibrillary tangles (NFTs) and neuronal dysfunction. Early onset AD (EOAD) is commonly caused by mutations in amyloid precursor protein (APP) or genes involved in the processing of APP including the presenilins (e.g. PSEN1 or PSEN2). In general, mouse models relevant to EOAD recapitulate amyloidosis, show only limited amounts of NFTs and neuronal cell dysfunction and low but significant levels of seizure susceptibility. To investigate the effect of genetic background on these phenotypes, we generated APPswe and PSEN1de9 transgenic mice on the seizure prone inbred strain background, DBA/2J. Previous studies show that the DBA/2J genetic background modifies plaque deposition in the presence of mutant APP but the impact of PSEN1de9 has not been tested. Our study shows that DBA/2J.APPswePSEN1de9 mice are significantly more prone to premature lethality, likely to due to lethal seizures, compared to B6.APPswePSEN1de9 mice—70% of DBA/2J.APPswePSEN1de9 mice die between 2-3 months of age. Of the DBA/2J.APPswePSEN1de9 mice that survived to 6 months of age, plaque deposition was greatly reduced compared to age-matched B6.APPswePSEN1de9 mice. The reduction in plaque deposition appears to be independent of microglia numbers, reactive astrocytosis and complement C5 activity.
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Affiliation(s)
| | - Kristen D. Onos
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | | | - Leah C. Graham
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- Sackler School of Medicine, Tufts University, Boston, United States of America
| | - Ellen C. Akeson
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Candice Byers
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | | | - Wayne N. Frankel
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Gareth R. Howell
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- Sackler School of Medicine, Tufts University, Boston, United States of America
- * E-mail:
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27
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Born HA. Seizures in Alzheimer's disease. Neuroscience 2014; 286:251-63. [PMID: 25484360 DOI: 10.1016/j.neuroscience.2014.11.051] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 11/12/2014] [Accepted: 11/24/2014] [Indexed: 10/24/2022]
Abstract
Alzheimer's disease (AD) increases the risk for late-onset seizures and neuronal network abnormalities. An elevated co-occurrence of AD and seizures has been established in the more prevalent sporadic form of AD. Recent evidence suggests that nonconvulsive network abnormalities, including seizures and other electroencephalographic abnormalities, may be more commonly found in patients than previously thought. Patients with familial AD are at an even greater risk for seizures, which have been found in patients with mutations in PSEN1, PSEN2, or APP, as well as with APP duplication. This review also provides an overview of seizure and electroencephalography studies in AD mouse models. The amyloid-β (Aβ) peptide has been identified as a possible link between AD and seizures, and while Aβ is known to affect neuronal activity, the full-length amyloid precursor protein (APP) and other APP cleavage products may be important for the development and maintenance of cortical network hyperexcitability. Nonconvulsive epileptiform activity, such as seizures or network abnormalities that are shorter in duration but may occur with higher frequency, may contribute to cognitive impairments characteristic of AD, such as amnestic wandering. Finally, the review discusses recent studies using antiepileptic drugs to rescue cognitive deficits in AD mouse models and human patients. Understanding the mechanistic link between epileptiform activity and AD is a research area of growing interest. Further understanding of the connection between neuronal hyperexcitability and Alzheimer's as well as the potential role of epileptiform activity in the progression of AD will be beneficial for improving treatment strategies.
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Affiliation(s)
- H A Born
- Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
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Duffy AM, Morales-Corraliza J, Bermudez-Hernandez KM, Schaner MJ, Magagna-Poveda A, Mathews PM, Scharfman HE. Entorhinal cortical defects in Tg2576 mice are present as early as 2-4 months of age. Neurobiol Aging 2014; 36:134-48. [PMID: 25109765 DOI: 10.1016/j.neurobiolaging.2014.07.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 06/30/2014] [Accepted: 07/08/2014] [Indexed: 11/15/2022]
Abstract
The entorhinal cortex (EC) is one of the first brain areas to display neuropathology in Alzheimer's disease. A mouse model which simulates amyloid-β (Aβ) neuropathology, the Tg2576 mouse, was used to address these early changes. Here, we show EC abnormalities occur in 2- to 4-month-old Tg2576 mice, an age before Aβ deposition and where previous studies suggest that there are few behavioral impairments. First we show, using a sandwich enzyme-linked immunosorbent assay, that soluble human Aβ40 and Aβ42 are detectable in the EC of 2-month-old Tg2576 mice before Aβ deposition. We then demonstrate that 2- to 4-month-old Tg2576 mice are impaired at object placement, an EC-dependent cognitive task. Next, we show that defects in neuronal nuclear antigen expression and myelin uptake occur in the superficial layers of the EC in 2- to 4-month-old Tg2576 mice. In slices from Tg2576 mice that contained the EC, there were repetitive field potentials evoked by a single stimulus to the underlying white matter, and a greater response to reduced extracellular magnesium ([Mg(2+)]o), suggesting increased excitability. However, deep layer neurons in Tg2576 mice had longer latencies to antidromic activation than wild type mice. The results show changes in the EC at early ages and suggest that altered excitability occurs before extensive plaque pathology.
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Affiliation(s)
- Aine M Duffy
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, New York, NY, USA; Department of Child & Adolescent Psychiatry, New York University Langone Medical Center, New York, NY, USA.
| | - Jose Morales-Corraliza
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, New York, NY, USA; Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | - Keria M Bermudez-Hernandez
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, New York, NY, USA; Department of Physiology & Neuroscience, Sackler Institute of Graduate Biomedical Sciences, New York University Langone Medical Center, New York, NY, USA
| | - Michael J Schaner
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, New York, NY, USA
| | - Alejandra Magagna-Poveda
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, New York, NY, USA
| | - Paul M Mathews
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, New York, NY, USA; Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | - Helen E Scharfman
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, New York, NY, USA; Department of Child & Adolescent Psychiatry, New York University Langone Medical Center, New York, NY, USA; Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA; Department of Physiology & Neuroscience, New York University Langone Medical Center, New York, NY, USA
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Stefanits H, Wesseling C, Kovacs GG. Loss of Calbindin immunoreactivity in the dentate gyrus distinguishes Alzheimer's disease from other neurodegenerative dementias. Neurosci Lett 2014; 566:137-41. [PMID: 24569123 DOI: 10.1016/j.neulet.2014.02.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 01/27/2014] [Accepted: 02/06/2014] [Indexed: 10/25/2022]
Abstract
Calbindin (Cb) is one of the major Ca(2+) binding proteins exhibiting neuromodulatory functions such as long-term potentiation (LTP), synaptic plasticity, and memory functions. It is expressed in hippocampal interneurons, pyramidal cells and granule cells of the dentate gyrus (DGCs). Cb mRNA levels remain stable during normal ageing, but decrease in Alzheimer's, Huntington, and Parkinson's disease. A recent study suggested a link between Aβ-induced Alzheimer's disease (AD)-related cognitive deficits and neuronal depletion of Cb. To evaluate whether this is specific for AD, we performed a comparative study of Cb immunoreactivity of DGCs in cases with AD-related neuropathologic change (49), grouped according to the stages of Braak and Braak, BB), Creutzfeldt-Jakob-disease (16), FTLD-tau Pick's disease type (PiD; 5), argyrophilic grain disease (8), and FTLD-TDP types A and B (6). The group of AD cases with BB stages V and VI showed the highest proportion of Cb negative cells in the DGC when compared to all other groups except PiD. The ratio of negative cells correlated significantly with the BB stages. While the total number of DGCs decreased with age in our series, loss of Cb immunoreactivity was shown to be age-dependent only in PiD and FTLD-TDP. We conclude, that late stage AD-neuropathologic change (BB V and VI stages) associates with significantly higher ratios of Cb negative DGCs and this correlates with advanced BB stage. This might suggest an accumulative effect of an epilepsy-like pathway on the Cb expression or the direct influence of local pathological protein deposits on the DGCs.
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Affiliation(s)
- Harald Stefanits
- Institute of Neurology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria; Department of Neurosurgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Carolin Wesseling
- Institute of Neurology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Gabor G Kovacs
- Institute of Neurology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
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Shahim P, Rejdak R, Ksiazek P, Blennow K, Zetterberg H, Mattsson N, Rejdak K. Cerebrospinal fluid biomarkers of β-amyloid metabolism and neuronal damage in epileptic seizures. Eur J Neurol 2013; 21:486-91. [DOI: 10.1111/ene.12336] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Accepted: 11/18/2013] [Indexed: 11/28/2022]
Affiliation(s)
- P. Shahim
- Clinical Neurochemistry Laboratory; Department of Psychiatry and Neurochemistry; Institute of Neuroscience and Physiology; University of Gothenburg; Sahlgrenska University Hospital/Mölndal; Mölndal Sweden
| | - R. Rejdak
- Department of General Ophthalmology; Medical University of Lublin; Lublin Poland
- Medical Research Center; Polish Academy of Sciences; Warsaw Poland
| | - P. Ksiazek
- Department of Public Health; Medical University of Lublin; Lublin Poland
| | - K. Blennow
- Clinical Neurochemistry Laboratory; Department of Psychiatry and Neurochemistry; Institute of Neuroscience and Physiology; University of Gothenburg; Sahlgrenska University Hospital/Mölndal; Mölndal Sweden
| | - H. Zetterberg
- Clinical Neurochemistry Laboratory; Department of Psychiatry and Neurochemistry; Institute of Neuroscience and Physiology; University of Gothenburg; Sahlgrenska University Hospital/Mölndal; Mölndal Sweden
- Department of Molecular Neuroscience and Reta Lilla Weston Laboratories; UCL Institute of Neurology; London UK
| | - N. Mattsson
- Clinical Neurochemistry Laboratory; Department of Psychiatry and Neurochemistry; Institute of Neuroscience and Physiology; University of Gothenburg; Sahlgrenska University Hospital/Mölndal; Mölndal Sweden
- San Francisco VA Medical Center; Center for Imaging of Neurodegenerative Diseases (CIND); University of California San Francisco; San Francisco CA USA
| | - K. Rejdak
- Medical Research Center; Polish Academy of Sciences; Warsaw Poland
- Department of Neurology; Medical University of Lublin; Lublin Poland
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31
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Brooks-Kayal AR, Bath KG, Berg AT, Galanopoulou AS, Holmes GL, Jensen FE, Kanner AM, O'Brien TJ, Whittemore VH, Winawer MR, Patel M, Scharfman HE. Issues related to symptomatic and disease-modifying treatments affecting cognitive and neuropsychiatric comorbidities of epilepsy. Epilepsia 2013; 54 Suppl 4:44-60. [PMID: 23909853 PMCID: PMC3924317 DOI: 10.1111/epi.12298] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Many symptoms of neurologic or psychiatric illness--such as cognitive impairment, depression, anxiety, attention deficits, and migraine--occur more frequently in people with epilepsy than in the general population. These diverse comorbidities present an underappreciated problem for people with epilepsy and their caregivers because they decrease quality of life, complicate treatment, and increase mortality. In fact, it has been suggested that comorbidities can have a greater effect on quality of life in people with epilepsy than the seizures themselves. There is increasing recognition of the frequency and impact of cognitive and behavioral comorbidities of epilepsy, highlighted in the 2012 Institute of Medicine report on epilepsy. Comorbidities have also been acknowledged, as a National Institutes of Health (NIH) Benchmark area for research in epilepsy. However, relatively little progress has been made in developing new therapies directed specifically at comorbidities. On the other hand, there have been many advances in understanding underlying mechanisms. These advances have made it possible to identify novel targets for therapy and prevention. As part of the International League Against Epilepsy/American Epilepsy Society workshop on preclinical therapy development for epilepsy, our working group considered the current state of understanding related to terminology, models, and strategies for therapy development for the comorbidities of epilepsy. Herein we summarize our findings and suggest ways to accelerate development of new therapies. We also consider important issues to improve research including those related to methodology, nonpharmacologic therapies, biomarkers, and infrastructure.
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Affiliation(s)
- Amy R Brooks-Kayal
- Departments of Pediatrics, Neurology and Pharmaceutical Sciences, University of Colorado Schools of Medicine and Pharmacy, Children's Hospital Colorado, Aurora, Colorado, USA.
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32
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García-Cabrero AM, Guerrero-López R, Giráldez BG, Llorens-Martín M, Avila J, Serratosa JM, Sánchez MP. Hyperexcitability and epileptic seizures in a model of frontotemporal dementia. Neurobiol Dis 2013; 58:200-8. [PMID: 23774255 DOI: 10.1016/j.nbd.2013.06.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 05/31/2013] [Accepted: 06/04/2013] [Indexed: 01/25/2023] Open
Abstract
Epileptic seizures are more common in patients with Alzheimer disease than in the general elderly population. Abnormal forms of hyperphosphorylated tau accumulate in Alzheimer disease and other tauopathies. Aggregates of tau are also found in patients with epilepsy and in experimental models of epilepsy. We report here the analysis of epileptic activity and neuropathological correlates of a transgenic line over-expressing human mutant tau, a model of frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17). The FTDP-17 model displays spontaneous epileptic activity and seizures with spike-wave complexes in the EEG, and a higher sensitivity to the GABAA receptor antagonist pentylenetetrazol (PTZ) when compared to age-matched controls, showing a notably increased seizure length and a shorter latency to develop severe seizures. FTDP-17 human tau mutants also display lower convulsive thresholds and higher lethality after PTZ injections. Astrocytosis and activated microglia are prominent in the hippocampus and other brain regions of young FTDP-17 mice where the human mutant tau transgene is expressed, before the appearance of hyperphosphorylated tau aggregates in these structures. FTDP-17 human mutant tau over-expression produces epilepsy and increased GABAA receptor-mediated hyperexcitability in the absence of Aβ pathology. Although aggregates of hyperphosphorylated tau have been observed in patients with epilepsy and in different chemically and electrically generated models of epilepsy, the FTDP-17 tau mutant analyzed here is the first model of genetically modified tau that presents with epilepsy. This model may represent a valuable tool to assay novel treatments in order to reduce tau pathology, a potential factor which may be involved in the development of epileptic seizures in dementia and other neurodegenerative diseases.
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33
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Iori V, Maroso M, Rizzi M, Iyer AM, Vertemara R, Carli M, Agresti A, Antonelli A, Bianchi ME, Aronica E, Ravizza T, Vezzani A. Receptor for Advanced Glycation Endproducts is upregulated in temporal lobe epilepsy and contributes to experimental seizures. Neurobiol Dis 2013; 58:102-14. [PMID: 23523633 DOI: 10.1016/j.nbd.2013.03.006] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 03/05/2013] [Accepted: 03/13/2013] [Indexed: 01/07/2023] Open
Abstract
Toll-like receptor 4 (TLR4) activation in neuron and astrocytes by High Mobility Group Box 1 (HMGB1) protein is a key mechanism of seizure generation. HMGB1 also activates the Receptor for Advanced Glycation Endproducts (RAGE), but it was unknown whether RAGE activation contributes to seizures or to HMGB1 proictogenic effects. We found that acute EEG seizures induced by 7ng intrahippocampal kainic acid (KA) were significantly reduced in Rage-/- mice relative to wild type (Wt) mice. The proictogenic effect of HMGB1 was decreased in Rage-/- mice, but less so, than in Tlr4-/- mice. In a mouse mesial temporal lobe epilepsy (mTLE) model, status epilepticus induced by 200ng intrahippocampal KA and the onset of the spontaneous epileptic activity were similar in Rage-/-, Tlr4-/- and Wt mice. However, the number of hippocampal paroxysmal episodes and their duration were both decreased in epileptic Rage-/- and Tlr4-/- mice vs Wt mice. All strains of epileptic mice displayed similar cognitive deficits in the novel object recognition test vs the corresponding control mice. CA1 neuronal cell loss was increased in epileptic Rage-/- vs epileptic Wt mice, while granule cell dispersion and doublecortin (DCX)-positive neurons were similarly affected. Notably, DCX neurons were preserved in epileptic Tlr4-/- mice. We did not find compensatory changes in HMGB1-related inflammatory signaling nor in glutamate receptor subunits in Rage-/- and Tlr4-/- naïve mice, except for ~20% NR2B subunit reduction in Rage-/- mice. RAGE was induced in neurons, astrocytes and microvessels in human and experimental mTLE hippocampi. We conclude that RAGE contributes to hyperexcitability underlying acute and chronic seizures, as well as to the proictogenic effects of HMGB1. RAGE and TLR4 play different roles in the neuropathologic sequelae developing after status epilepticus. These findings reveal new molecular mechanisms underlying seizures, cell loss and neurogenesis which involve inflammatory pathways upregulated in human epilepsy.
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Affiliation(s)
- Valentina Iori
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy
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Scharfman HE, Myers CE. Hilar mossy cells of the dentate gyrus: a historical perspective. Front Neural Circuits 2013; 6:106. [PMID: 23420672 PMCID: PMC3572871 DOI: 10.3389/fncir.2012.00106] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 12/02/2012] [Indexed: 11/24/2022] Open
Abstract
The circuitry of the dentate gyrus (DG) of the hippocampus is unique compared to other hippocampal subfields because there are two glutamatergic principal cells instead of one: granule cells, which are the vast majority of the cells in the DG, and the so-called “mossy cells.” The distinctive appearance of mossy cells, the extensive divergence of their axons, and their vulnerability to excitotoxicity relative to granule cells has led to a great deal of interest in mossy cells. Nevertheless, there is no consensus about the normal functions of mossy cells and the implications of their vulnerability. There even seems to be some ambiguity about exactly what mossy cells are. Here we review initial studies of mossy cells, characteristics that define them, and suggest a practical definition to allow investigators to distinguish mossy cells from other hilar neurons even if all morphological and physiological information is unavailable due to technical limitations of their experiments. In addition, hypotheses are discussed about the role of mossy cells in the DG network, reasons for their vulnerability and their implications for disease.
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Affiliation(s)
- Helen E Scharfman
- New York University Langone Medical Center New York, NY, USA ; Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research Orangeburg, NY, USA
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