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Griffin EF, Yan X, Caldwell KA, Caldwell GA. Distinct functional roles of Vps41-mediated neuroprotection in Alzheimer's and Parkinson's disease models of neurodegeneration. Hum Mol Genet 2019; 27:4176-4193. [PMID: 30508205 DOI: 10.1093/hmg/ddy308] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Accepted: 08/21/2018] [Indexed: 12/25/2022] Open
Abstract
Commonalities and, in some cases, pathological overlap between neurodegenerative diseases have led to speculation that targeting of underlying mechanisms might be of potentially shared therapeutic benefit. Alzheimer's disease is characterized by the formation of plaques, composed primarily of the amyloid-β 1-42 (Aβ) peptide in the brain, resulting in neurodegeneration. Previously, we have shown that overexpression of the lysosomal-trafficking protein, human Vps41 (hVps41), is neuroprotective in a transgenic worm model of Parkinson's disease, wherein progressive dopaminergic neurodegeneration is induced by α-synuclein overexpression. Here, we report the results of a systematic comparison of hVps41-mediated neuroprotection between α-synuclein and Aβ in transgenic nematode models of Caenorhabditis elegans. Our results indicate that an ARF-like GTPase gene product, ARL-8, mitigates endocytic Aβ neurodegeneration in a VPS-41-dependent manner, rather than through RAB-7 and AP3 as with α-synuclein. Furthermore, the neuroprotective effect of ARL-8 or hVps41 appears to be dependent on their colocalization and the activity of ARL-8. Additionally, we demonstrate that the LC3 orthologue, LGG-2, plays a critical role in Aβ toxicity with ARL-8. Further analysis of functional effectors of Aβ protein processing via the lysosomal pathway will assist in the elucidation of the underlying mechanism involving VPS-41-mediated neuroprotection. These results reveal functional distinctions in the intracellular management of neurotoxic proteins that serve to better inform the path for development of therapeutic interventions to halt neurodegeneration.
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Affiliation(s)
- Edward F Griffin
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA
| | | | - Kim A Caldwell
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA.,Departments of Neurology and Neurobiology, Center for Neurodegeneration and Experimental Therapeutics, Nathan Shock Center for Research on the Basic Biology of Aging, University of Alabama at Birmingham School of Medicine, Birmingham, AL, USA
| | - Guy A Caldwell
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA.,Departments of Neurology and Neurobiology, Center for Neurodegeneration and Experimental Therapeutics, Nathan Shock Center for Research on the Basic Biology of Aging, University of Alabama at Birmingham School of Medicine, Birmingham, AL, USA
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52
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Quevenco FC, Schreiner SJ, Preti MG, van Bergen JMG, Kirchner T, Wyss M, Steininger SC, Gietl A, Leh SE, Buck A, Pruessmann KP, Hock C, Nitsch RM, Henning A, Van De Ville D, Unschuld PG. GABA and glutamate moderate beta-amyloid related functional connectivity in cognitively unimpaired old-aged adults. NEUROIMAGE-CLINICAL 2019; 22:101776. [PMID: 30927605 PMCID: PMC6439267 DOI: 10.1016/j.nicl.2019.101776] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 02/03/2019] [Accepted: 03/10/2019] [Indexed: 02/08/2023]
Abstract
Background Effects of beta-amyloid accumulation on neuronal function precede the clinical manifestation of Alzheimer's disease (AD) by years and affect distinct cognitive brain networks. As previous studies suggest a link between beta-amyloid and dysregulation of excitatory and inhibitory neurotransmitters, we aimed to investigate the impact of GABA and glutamate on beta-amyloid related functional connectivity. Methods 29 cognitively unimpaired old-aged adults (age = 70.03 ± 5.77 years) were administered 11C-Pittsburgh Compound B (PiB) positron-emission tomography (PET), and MRI at 7 Tesla (7T) including blood oxygen level dependent (BOLD) functional MRI (fMRI) at rest for measuring static and dynamic functional connectivity. An advanced 7T MR spectroscopic imaging (MRSI) sequence based on the free induction decay acquisition localized by outer volume suppression’ (FIDLOVS) technology was used for gray matter specific measures of GABA and glutamate in the posterior cingulate and precuneus (PCP) region. Results GABA and glutamate MR-spectra indicated significantly higher levels in gray matter than in white matter. A global effect of beta-amyloid on functional connectivity in the frontal, occipital and inferior temporal lobes was observable. Interactive effects of beta-amyloid with gray matter GABA displayed positive PCP connectivity to the frontomedial regions, and the interaction of beta-amyloid with gray matter glutamate indicated positive PCP connectivity to frontal and cerebellar regions. Furthermore, decreased whole-brain but increased fronto-occipital and temporo-parietal dynamic connectivity was found, when GABA interacted with regional beta-amyloid deposits in the amygdala, frontal lobe, hippocampus, insula and striatum. Conclusions GABA, and less so glutamate, may moderate beta-amyloid related functional connectivity. Additional research is needed to better characterize their interaction and potential impact on AD. Combined ultra-high fieldstrength FIDLOVS MRSI at 7 Tesla with 11C-PIB PET. Assessment of gray matter specific levels of GABA and glutamate. Identification of interactive effects of GABA, glutamate and beta-Amyloid. GABA may moderate dysfunctional beta-Amyloid effects on pre-clinical brain pathology.
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Affiliation(s)
- F C Quevenco
- Institute for Regenerative Medicine (IREM), University of Zurich, Zurich, Switzerland
| | - S J Schreiner
- Institute for Regenerative Medicine (IREM), University of Zurich, Zurich, Switzerland; Hospital for Psychogeriatric Medicine, Psychiatric University Hospital Zurich (PUK), Zurich, Switzerland
| | - M G Preti
- Department of Radiology and Medical Informatics, Université de Genève, Switzerland; Institute of Bioengineering, École polytechnique fédérale de Lausanne, Switzerland
| | - J M G van Bergen
- Institute for Regenerative Medicine (IREM), University of Zurich, Zurich, Switzerland
| | - T Kirchner
- Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland
| | - M Wyss
- Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland
| | - S C Steininger
- Institute for Regenerative Medicine (IREM), University of Zurich, Zurich, Switzerland; Hospital for Psychogeriatric Medicine, Psychiatric University Hospital Zurich (PUK), Zurich, Switzerland
| | - A Gietl
- Institute for Regenerative Medicine (IREM), University of Zurich, Zurich, Switzerland
| | - S E Leh
- Institute for Regenerative Medicine (IREM), University of Zurich, Zurich, Switzerland; Hospital for Psychogeriatric Medicine, Psychiatric University Hospital Zurich (PUK), Zurich, Switzerland
| | - A Buck
- Division of Nuclear Medicine, University Hospital Zurich (USZ), Zurich, Switzerland
| | - K P Pruessmann
- Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland; Neuroscience Center Zurich (ZNZ), Zurich, Switzerland
| | - C Hock
- Institute for Regenerative Medicine (IREM), University of Zurich, Zurich, Switzerland; Hospital for Psychogeriatric Medicine, Psychiatric University Hospital Zurich (PUK), Zurich, Switzerland; Neuroscience Center Zurich (ZNZ), Zurich, Switzerland
| | - R M Nitsch
- Institute for Regenerative Medicine (IREM), University of Zurich, Zurich, Switzerland; Hospital for Psychogeriatric Medicine, Psychiatric University Hospital Zurich (PUK), Zurich, Switzerland; Neuroscience Center Zurich (ZNZ), Zurich, Switzerland
| | - A Henning
- Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland; Max Planck Institute for Biological Cybernetics, Tubingen, Germany
| | - D Van De Ville
- Department of Radiology and Medical Informatics, Université de Genève, Switzerland; Institute of Bioengineering, École polytechnique fédérale de Lausanne, Switzerland
| | - P G Unschuld
- Institute for Regenerative Medicine (IREM), University of Zurich, Zurich, Switzerland; Hospital for Psychogeriatric Medicine, Psychiatric University Hospital Zurich (PUK), Zurich, Switzerland; Neuroscience Center Zurich (ZNZ), Zurich, Switzerland.
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53
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Mele M, Costa RO, Duarte CB. Alterations in GABA A-Receptor Trafficking and Synaptic Dysfunction in Brain Disorders. Front Cell Neurosci 2019; 13:77. [PMID: 30899215 PMCID: PMC6416223 DOI: 10.3389/fncel.2019.00077] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 02/15/2019] [Indexed: 12/12/2022] Open
Abstract
GABAA receptors (GABAAR) are the major players in fast inhibitory neurotransmission in the central nervous system (CNS). Regulation of GABAAR trafficking and the control of their surface expression play important roles in the modulation of the strength of synaptic inhibition. Different pieces of evidence show that alterations in the surface distribution of GABAAR and dysregulation of their turnover impair the activity of inhibitory synapses. A diminished efficacy of inhibitory neurotransmission affects the excitatory/inhibitory balance and is a common feature of various disorders of the CNS characterized by an increased excitability of neuronal networks. The synaptic pool of GABAAR is mainly controlled through regulation of internalization, recycling and lateral diffusion of the receptors. Under physiological condition these mechanisms are finely coordinated to define the strength of GABAergic synapses. In this review article, we focus on the alteration in GABAAR trafficking with an impact on the function of inhibitory synapses in various disorders of the CNS. In particular we discuss how similar molecular mechanisms affecting the synaptic distribution of GABAAR and consequently the excitatory/inhibitory balance may be associated with a wide diversity of pathologies of the CNS, from psychiatric disorders to acute alterations leading to neuronal death. A better understanding of the cellular and molecular mechanisms that contribute to the impairment of GABAergic neurotransmission in these disorders, in particular the alterations in GABAAR trafficking and surface distribution, may lead to the identification of new pharmacological targets and to the development of novel therapeutic strategies.
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Affiliation(s)
- Miranda Mele
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Rui O Costa
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Carlos B Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Department of Life Sciences, University of Coimbra, Coimbra, Portugal
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54
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Unsupervised excitation: GABAergic dysfunctions in Alzheimer’s disease. Brain Res 2019; 1707:216-226. [DOI: 10.1016/j.brainres.2018.11.042] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 10/31/2018] [Accepted: 11/27/2018] [Indexed: 12/22/2022]
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55
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Griffin EF, Scopel SE, Stephen CA, Holzhauer AC, Vaji MA, Tuckey RA, Berkowitz LA, Caldwell KA, Caldwell GA. ApoE-associated modulation of neuroprotection from Aβ-mediated neurodegeneration in transgenic Caenorhabditis elegans. Dis Model Mech 2019; 12:dmm.037218. [PMID: 30683808 PMCID: PMC6398492 DOI: 10.1242/dmm.037218] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 01/17/2019] [Indexed: 12/13/2022] Open
Abstract
Allele-specific distinctions in the human apolipoprotein E (APOE) locus represent the best-characterized genetic predictor of Alzheimer's disease (AD) risk. Expression of isoform APOEε2 is associated with reduced risk, while APOEε3 is neutral and APOEε4 carriers exhibit increased susceptibility. Using Caenorhabditis elegans, we generated a novel suite of humanized transgenic nematodes to facilitate neuronal modeling of amyloid-beta peptide (Aβ) co-expression in the context of distinct human APOE alleles. We found that co-expression of human APOEε2 with Aβ attenuated Aβ-induced neurodegeneration, whereas expression of the APOEε4 allele had no effect on neurodegeneration, indicating a loss of neuroprotective capacity. Notably, the APOEε3 allele displayed an intermediate phenotype; it was not neuroprotective in young adults but attenuated neurodegeneration in older animals. There was no functional impact from the three APOE isoforms in the absence of Aβ co-expression. Pharmacological treatment that examined neuroprotective effects of APOE alleles on calcium homeostasis showed allele-specific responses to changes in ER-associated calcium dynamics in the Aβ background. Additionally, Aβ suppressed survival, an effect that was rescued by APOEε2 and APOEε3, but not APOEε4. Expression of the APOE alleles in neurons, independent of Aβ, exerted no impact on survival. Taken together, these results illustrate that C. elegans provides a powerful in vivo platform with which to explore how AD-associated neuronal pathways are modulated by distinct APOE gene products in the context of Aβ-associated neurotoxicity. The significance of both ApoE and Aβ to AD highlights the utility of this new pre-clinical model as a means to dissect their functional inter-relationship.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Edward F Griffin
- Department of Biological Sciences, The University of Alabama, Box 870344, Tuscaloosa, AL 35487-0344, USA
| | - Samuel E Scopel
- Department of Biological Sciences, The University of Alabama, Box 870344, Tuscaloosa, AL 35487-0344, USA
| | - Cayman A Stephen
- Department of Biological Sciences, The University of Alabama, Box 870344, Tuscaloosa, AL 35487-0344, USA
| | - Adam C Holzhauer
- Department of Biological Sciences, The University of Alabama, Box 870344, Tuscaloosa, AL 35487-0344, USA
| | - Madeline A Vaji
- Department of Biological Sciences, The University of Alabama, Box 870344, Tuscaloosa, AL 35487-0344, USA
| | - Ryan A Tuckey
- Department of Biological Sciences, The University of Alabama, Box 870344, Tuscaloosa, AL 35487-0344, USA
| | - Laura A Berkowitz
- Department of Biological Sciences, The University of Alabama, Box 870344, Tuscaloosa, AL 35487-0344, USA
| | - Kim A Caldwell
- Department of Biological Sciences, The University of Alabama, Box 870344, Tuscaloosa, AL 35487-0344, USA.,Departments of Neurology and Neurobiology, Center for Neurodegeneration and Experimental Therapeutics, Nathan Shock Center for Research on the Basic Biology of Aging, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
| | - Guy A Caldwell
- Department of Biological Sciences, The University of Alabama, Box 870344, Tuscaloosa, AL 35487-0344, USA .,Departments of Neurology and Neurobiology, Center for Neurodegeneration and Experimental Therapeutics, Nathan Shock Center for Research on the Basic Biology of Aging, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
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56
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Sun J, Martin JM, Vanderpoel V, Sumbria RK. The Promises and Challenges of Erythropoietin for Treatment of Alzheimer's Disease. Neuromolecular Med 2019; 21:12-24. [PMID: 30656553 DOI: 10.1007/s12017-019-08524-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 01/08/2019] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder in the world, and intracellular neurofibrillary tangles and extracellular amyloid-beta protein deposits represent the major pathological hallmarks of the disease. Currently available treatments provide some symptomatic relief but fail to modify primary pathological processes that underlie the disease. Erythropoietin (EPO), a hematopoietic growth factor, acts primarily to stimulate erythroid cell production, and is clinically used to treat anemia. EPO has evolved as a therapeutic agent for neurodegeneration and has improved neurological outcomes and AD pathology in rodents. However, penetration of the blood-brain barrier (BBB) and negative hematopoietic effects are the two major challenges for the therapeutic development of EPO for chronic neurodegenerative diseases like AD. The transferrin receptors at the BBB, which are responsible for transporting transferrin-bound iron from the blood into the brain parenchyma, can be used to shuttle therapeutic molecules across the BBB. In this review, we discuss the role of EPO as a potential neurotherapeutic for AD, challenges associated with EPO development for AD, and targeting the BBB transferrin receptor for EPO brain delivery.
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Affiliation(s)
- Jiahong Sun
- Department of Biopharmaceutical Sciences, School of Pharmacy and Health Sciences, Keck Graduate Institute, 535 Watson Dr, Claremont, CA, 91711, USA
| | - Jan Michelle Martin
- College of Medicine, California Northstate University, Elk Grove, CA, 95757, USA
| | | | - Rachita K Sumbria
- Department of Biopharmaceutical Sciences, School of Pharmacy and Health Sciences, Keck Graduate Institute, 535 Watson Dr, Claremont, CA, 91711, USA. .,Department of Neurology, University of California, Irvine, CA, 92868, USA.
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57
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Diagnostic and prognostic biomarkers for HAND. J Neurovirol 2019; 25:686-701. [PMID: 30607890 DOI: 10.1007/s13365-018-0705-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 11/13/2018] [Accepted: 11/16/2018] [Indexed: 02/06/2023]
Abstract
In 2007, the nosology for HIV-1-associated neurocognitive disorders (HAND) was updated to a primarily neurocognitive disorder. However, currently available diagnostic tools lack the sensitivity and specificity needed for an accurate diagnosis for HAND. Scientists and clinicians, therefore, have been on a quest for an innovative biomarker to diagnose (i.e., diagnostic biomarker) and/or predict (i.e., prognostic biomarker) the progression of HAND in the post-combination antiretroviral therapy (cART) era. The present review examined the utility and challenges of four proposed biomarkers, including neurofilament light (NFL) chain concentration, amyloid (i.e., sAPPα, sAPPβ, amyloid β) and tau proteins (i.e., total tau, phosphorylated tau), resting-state functional magnetic resonance imaging (fMRI), and prepulse inhibition (PPI). Although significant genotypic differences have been observed in NFL chain concentration, sAPPα, sAPPβ, amyloid β, total tau, phosphorylated tau, and resting-state fMRI, inconsistencies and/or assessment limitations (e.g., invasive procedures, lack of disease specificity, cost) challenge their utility as a diagnostic and/or prognostic biomarker for milder forms of neurocognitive impairment (NCI) in the post-cART era. However, critical evaluation of the literature supports the utility of PPI as a powerful diagnostic biomarker with high accuracy (i.e., 86.7-97.1%), sensitivity (i.e., 89.3-100%), and specificity (i.e., 79.5-94.1%). Additionally, the inclusion of multiple CSF and/or plasma markers, rather than a single protein, may provide a more sensitive diagnostic biomarker for HAND; however, a pressing need for additional research remains. Most notably, PPI may serve as a prognostic biomarker for milder forms of NCI, evidenced by its ability to predict later NCI in higher-order cognitive domains with regression coefficients (i.e., r) greater than 0.8. Thus, PPI heralds an opportunity for the development of a brief, noninvasive diagnostic and promising prognostic biomarker for milder forms of NCI in the post-cART era.
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58
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Wu X, Lv YG, Du YF, Chen F, Reed MN, Hu M, Suppiramaniam V, Tang SS, Hong H. Neuroprotective effects of INT-777 against Aβ 1-42-induced cognitive impairment, neuroinflammation, apoptosis, and synaptic dysfunction in mice. Brain Behav Immun 2018; 73:533-545. [PMID: 29935310 DOI: 10.1016/j.bbi.2018.06.018] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 06/14/2018] [Accepted: 06/20/2018] [Indexed: 12/14/2022] Open
Abstract
Increasing evidence demonstrates that the neurotoxicity of amyloid-beta (Aβ) deposition plays a causative role in Alzheimer's disease (AD). Herein, we evaluated the neuroprotective effects of 6α-ethyl-23(S)-methylcholic acid (S-EMCA, INT-777), a specific G-protein coupled bile acid receptor 1 (TGR5) agonist, in the Aβ1-42-treated mouse model of acute neurotoxicity. Single intracerebroventricular (i.c.v.) injection of aggregated Aβ1-42 (410 pmol/mouse; 5 μl) into the mouse brain induced cognitive impairment, neuroinflammation, apoptosis, and synaptic dysfunction. In contrast, INT-777 (1.5 or 3.0 μg/mouse, i.c.v.) significantly improved Aβ1-42-induced cognitive impairment, as reflected by better performance in memory tests. Importantly, INT-777 treatment reversed Aβ1-42-induced TGR5 down-regulation, suppressed the increase of nuclear NF-κB p65, and mitigated neuroinflammation, as evidenced by lower proinflammatory cytokines and less Iba1-positive cells in the hippocampus and frontal cortex. INT-777 treatment also pronouncedly suppressed apoptosis through the reduction of TUNEL-positive cells, decreased caspase-3 activation, increased the ratio of Bcl-2/Bax, and ameliorated synaptic dysfunction by promoting dendritic spine generation with the upregulation of postsynaptic and presynaptic proteins (PSD95 and synaptophysin) in Aβ1-42-treated mice. Our results indicate that INT-777 has potent neuroprotective effects against Aβ1-42-induced neurotoxicity. Taken together, these findings suggest that the activation of TGR5 could be a novel and promising strategy for the treatment of AD.
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Affiliation(s)
- Xian Wu
- Department of Pharmacology, Key Laboratory of Neuropsychiatric Diseases, China Pharmaceutical University, Nanjing 210009, China
| | - Yang-Ge Lv
- Department of Pharmacology, Key Laboratory of Neuropsychiatric Diseases, China Pharmaceutical University, Nanjing 210009, China
| | - Yi-Feng Du
- Department of Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Fang Chen
- Department of Pharmacology, Key Laboratory of Neuropsychiatric Diseases, China Pharmaceutical University, Nanjing 210009, China
| | - Miranda N Reed
- Department of Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Mei Hu
- Department of Pharmacology, Key Laboratory of Neuropsychiatric Diseases, China Pharmaceutical University, Nanjing 210009, China
| | - Vishnu Suppiramaniam
- Department of Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Su-Su Tang
- Department of Pharmacology, Key Laboratory of Neuropsychiatric Diseases, China Pharmaceutical University, Nanjing 210009, China.
| | - Hao Hong
- Department of Pharmacology, Key Laboratory of Neuropsychiatric Diseases, China Pharmaceutical University, Nanjing 210009, China.
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59
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Jin N, Lipponen A, Koivisto H, Gurevicius K, Tanila H. Increased cortical beta power and spike-wave discharges in middle-aged APP/PS1 mice. Neurobiol Aging 2018; 71:127-141. [PMID: 30138766 DOI: 10.1016/j.neurobiolaging.2018.07.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 06/12/2018] [Accepted: 07/14/2018] [Indexed: 12/11/2022]
Abstract
Amyloid plaque-forming transgenic mice display neuronal hyperexcitability, epilepsy, and sudden deaths in early adulthood. However, it is unknown whether hyperexcitability persists until middle ages when memory impairment manifests. We recorded multichannel video electroencephalography (EEG), local field potentials, and auditory evoked potentials in transgenic mice carrying mutated human amyloid precursor protein (APP) and presenilin-1 (PS1) genes and wild-type littermates at 14-16 months and compared the results with data we have earlier collected from 4-month-old mice. Furthermore, we monitored acoustic startle responses in other APP/PS1 and wild-type mice from 3 to 11 months of age. Independent of the age APP/PS1 mice demonstrated increased cortical power at 8-60 Hz. They also displayed over 5-fold increase in the occurrence of spike-wave discharges and augmented auditory evoked potentials compared with nontransgenic littermates. In contrast to evoked potentials, APP/PS1 mice showed normalization of acoustic startle responses with aging. Increased cortical power and spike-wave discharges provide powerful new biomarkers to monitor progression of amyloid pathology in preclinical intervention studies.
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Affiliation(s)
- Nanxiang Jin
- A. I. Virtanen Institute, University of Eastern Finland, Kuopio, Finland
| | - Arto Lipponen
- A. I. Virtanen Institute, University of Eastern Finland, Kuopio, Finland
| | | | | | - Heikki Tanila
- A. I. Virtanen Institute, University of Eastern Finland, Kuopio, Finland.
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60
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Ross JA, Gliebus G, Van Bockstaele EJ. Stress induced neural reorganization: A conceptual framework linking depression and Alzheimer's disease. Prog Neuropsychopharmacol Biol Psychiatry 2018; 85:136-151. [PMID: 28803923 PMCID: PMC5809232 DOI: 10.1016/j.pnpbp.2017.08.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 08/04/2017] [Accepted: 08/06/2017] [Indexed: 12/29/2022]
Abstract
Chronic stress is a risk factor for a number of physiological disorders including cardiovascular disease, obesity and gastrointestinal disorders, as well as psychiatric and neurodegenerative disorders. There are a number of underlying molecular and cellular mechanisms altered in the course of chronic stress, which may increase the vulnerability of individuals to develop psychiatric disorders such as depression, and neurodegenerative disorders such as Alzheimer's Disease (AD). This is evident in the influence of stress on large-scale brain networks, including the resting state Default Mode Network (DMN), the effects of stress on neuronal circuitry and architecture, and the cellular and molecular adaptations to stress, which may render individuals with stress related psychiatric disorders more vulnerable to neurodegenerative disease later in life. These alterations include decreased negative feedback inhibition of the hypothalamic pituitary axis (HPA) axis, decreased dendritic arborization and spine density in the prefrontal cortex (PFC) and hippocampus, and the release of proinflammatory cytokines, which may suppress neurogenesis and promote neuronal cell death. Each of these factors are thought to play a role in stress-related psychiatric disease as well as AD, and have been observed in clinical and post-mortem studies of individuals with depression and AD. The goal of the current review is to summarize clinical and preclinical evidence supporting a role for chronic stress as a putative link between neuropsychiatric and neurodegenerative disease. Moreover, we provide a rationale for the importance of taking a medical history of stress-related psychiatric diseases into consideration during clinical trial design, as they may play an important role in the etiology of AD in stratified patient populations.
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Affiliation(s)
- Jennifer A. Ross
- Department of Pharmacology and Physiology, College of Medicine, Drexel University, Philadelphia, PA 19102
| | - Gediminas Gliebus
- Department of Neurology, Drexel Neuroscience Institute, Philadelphia, PA 19107
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61
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Zhang D, Mably AJ, Walsh DM, Rowan MJ. Peripheral Interventions Enhancing Brain Glutamate Homeostasis Relieve Amyloid β- and TNFα- Mediated Synaptic Plasticity Disruption in the Rat Hippocampus. Cereb Cortex 2018; 27:3724-3735. [PMID: 27390019 DOI: 10.1093/cercor/bhw193] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Dysregulation of glutamate homeostasis in the interstitial fluid of the brain is strongly implicated in causing synaptic dysfunction in many neurological and psychiatric illnesses. In the case of Alzheimer's disease (AD), amyloid β (Aβ)-mediated disruption of synaptic plasticity and memory can be alleviated by interventions that directly remove glutamate or block certain glutamate receptors. An alternative strategy is to facilitate the removal of excess glutamate from the nervous system by activating peripheral glutamate clearance systems. One such blood-based system, glutamate oxaloacetate transaminase (GOT), is activated by oxaloacetate, which acts as a co-substrate. We report here that synthetic and AD brain-derived Aβ-mediated inhibition of synaptic long-term potentiation in the hippocampus is alleviated by oxaloacetate. Moreover the effect of oxaloacetate was GOT-dependent. The disruptive effects of a general inhibitor of excitatory amino acid transport or TNFα, a pro-inflammatory mediator of Aβ action, were also reversed by oxaloacetate. Furthermore, another intervention that increases peripheral glutamate clearance, peritoneal dialysis, mimicked the beneficial effect of oxaloacetate. These findings lend support to the promotion of the peripheral clearance of glutamate as a means to alleviate synaptic dysfunction that is caused by impaired glutamate homeostasis in the brain.
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Affiliation(s)
- Dainan Zhang
- Department of Pharmacology and Therapeutics, and Trinity College Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Alexandra J Mably
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham & Women's Hospital, Harvard Institute of Medicine, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham & Women's Hospital, Harvard Institute of Medicine, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Michael J Rowan
- Department of Pharmacology and Therapeutics, and Trinity College Institute of Neuroscience, Trinity College, Dublin 2, Ireland
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Yin Y, Zhao Y, Han S, Zhang N, Chen H, Wang X. Autophagy-ERK1/2-Involved Disinhibition of Hippocampal Neurons Contributes to the Pre-Synaptic Toxicity Induced by Aβ42 Exposure. J Alzheimers Dis 2018; 59:851-869. [PMID: 28697568 DOI: 10.3233/jad-170246] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease and the most frequent cause of progressive cognitive decline in the elderly population. To date, there is still no effective treatment for AD, requiring more underlying mechanisms. In the present study, we investigated the effects of Aβ42 on the inhibitory synaptic transmission in the cultured hippocampal neurons, and explored the possible mechanism. The frequency, but not amplitude, of miniature inhibitory post-synaptic currents was significantly suppressed by Aβ42, indicating that Aβ42 played its role in inhibitory transmitter release at the pre-synaptic sites. Aβ42 had no effect on miniature excitatory post-synaptic currents, suggesting GABAergic synapses are more susceptible to Aβ42 exposure. However, the number of GABAergic neurons or synapses was not influenced, suggesting the corresponding stage may be a preclinical one. The effect of Aβ42 can be mimicked by PD98059 (an inhibitor of ERK1/2) and blocked by curcumin (an activator of MEK), which reveals Aβ-involved influence is via the decreased phosphorylation of MAPK-ERK1/2. In addition, synaptophysin is confirmed to be a downstream protein of MAPK-ERK1/2 at the pre-synaptic site. At the same time, suppressed autophagy was observed after Aβ42 exposure, and the activation of autophagy increased pERK1/2 level and salvaged the disinhibition of hippocampal neurons. These data suggest that diminished GABAergic tone likely starts from the preclinical stage of AD, so some GABAergic stress test may be effective for identifying cognitively normal elder adults. Strategies against the dysfunction of autophagy should be adopted in the early stage of AD because of its initial effects.
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Affiliation(s)
- Yanling Yin
- Department of Neurobiology and Beijing Institute for Brain Disorders, School of Basic Medical Sciences, Capital Medical University, Beijing, PR China
| | - Yuanyuan Zhao
- Core Facility Center, Capital Medical University, Beijing, PR China
| | - Song Han
- Department of Neurobiology and Beijing Institute for Brain Disorders, School of Basic Medical Sciences, Capital Medical University, Beijing, PR China
| | - Nan Zhang
- Department of Human Anatomy, School of Basic Medical Sciences, Capital Medical University, Beijing, PRChina
| | - Hanyu Chen
- Wyoming Seminary College Preparatory School, Kingston, PA, USA
| | - Xiaomin Wang
- Department of Neurobiology and Beijing Institute for Brain Disorders, School of Basic Medical Sciences, Capital Medical University, Beijing, PR China
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63
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Ross JA, Reyes BAS, Van Bockstaele EJ. Amyloid beta peptides, locus coeruleus-norepinephrine system and dense core vesicles. Brain Res 2018; 1702:46-53. [PMID: 29577889 DOI: 10.1016/j.brainres.2018.03.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 03/06/2018] [Accepted: 03/07/2018] [Indexed: 10/17/2022]
Abstract
The evolution of peptidergic signaling systems in the central nervous system serves a distinct and crucial role in brain processes and function. The diversity of physiological peptides and the complexity of their regulation and secretion from the dense core vesicles (DCV) throughout the brain is a topic greatly in need of investigation, though recent years have shed light on cellular and molecular mechanisms that are summarized in this review. Here, we focus on the convergence of peptidergic systems onto the Locus Coeruleus (LC), the sole provider of norepinephrine (NE) to the cortex and hippocampus, via large DCV. As the LC-NE system is one of the first regions of the brain to undergo degeneration in Alzheimer's Disease (AD), and markers of DCV have consistently been demonstrated to have biomarker potential for AD progression, here we summarize the current literature linking the LC-NE system with DCV dysregulation and Aβ peptides. We also include neuroanatomical data suggesting that the building blocks of senile plaques, Aβ monomers, may be localized to DCV of the LC and noradrenergic axon terminals of the prefrontal cortex. Finally, we explore the putative consequences of chronic stress on Aβ production and the role that DCV may play in LC degeneration. Clinical data of immunological markers of DCV in AD patients are discussed.
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Affiliation(s)
- Jennifer A Ross
- Department of Pharmacology and Physiology, College of Medicine, Drexel University, Philadelphia, PA 19102, United States.
| | - Beverly A S Reyes
- Department of Pharmacology and Physiology, College of Medicine, Drexel University, Philadelphia, PA 19102, United States
| | - Elisabeth J Van Bockstaele
- Department of Pharmacology and Physiology, College of Medicine, Drexel University, Philadelphia, PA 19102, United States
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Lorenz-Guertin JM, Jacob TC. GABA type a receptor trafficking and the architecture of synaptic inhibition. Dev Neurobiol 2018; 78:238-270. [PMID: 28901728 PMCID: PMC6589839 DOI: 10.1002/dneu.22536] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/08/2017] [Accepted: 09/08/2017] [Indexed: 12/21/2022]
Abstract
Ubiquitous expression of GABA type A receptors (GABAA R) in the central nervous system establishes their central role in coordinating most aspects of neural function and development. Dysregulation of GABAergic neurotransmission manifests in a number of human health disorders and conditions that in certain cases can be alleviated by drugs targeting these receptors. Precise changes in the quantity or activity of GABAA Rs localized at the cell surface and at GABAergic postsynaptic sites directly impact the strength of inhibition. The molecular mechanisms constituting receptor trafficking to and from these compartments therefore dictate the efficacy of GABAA R function. Here we review the current understanding of how GABAA Rs traffic through biogenesis, plasma membrane transport, and degradation. Emphasis is placed on discussing novel GABAergic synaptic proteins, receptor and scaffolding post-translational modifications, activity-dependent changes in GABAA R confinement, and neuropeptide and neurosteroid mediated changes. We further highlight modern techniques currently advancing the knowledge of GABAA R trafficking and clinically relevant neurodevelopmental diseases connected to GABAergic dysfunction. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 238-270, 2018.
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Affiliation(s)
- Joshua M Lorenz-Guertin
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, 15261
| | - Tija C Jacob
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, 15261
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Ren SQ, Yao W, Yan JZ, Jin C, Yin JJ, Yuan J, Yu S, Cheng Z. Amyloid β causes excitation/inhibition imbalance through dopamine receptor 1-dependent disruption of fast-spiking GABAergic input in anterior cingulate cortex. Sci Rep 2018; 8:302. [PMID: 29321592 PMCID: PMC5762926 DOI: 10.1038/s41598-017-18729-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 12/17/2017] [Indexed: 11/21/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common cause of dementia in the elderly. At the early stages of AD development, the soluble β-amyloid (Aβ) induces synaptic dysfunction, perturbs the excitation/inhibition balance of neural circuitries, and in turn alters the normal neural network activity leading to cognitive decline, but the underlying mechanisms are not well established. Here by using whole-cell recordings in acute mouse brain slices, we found that 50 nM Aβ induces hyperexcitability of excitatory pyramidal cells in the cingulate cortex, one of the most vulnerable areas in AD, via depressing inhibitory synaptic transmission. Furthermore, by simultaneously recording multiple cells, we discovered that the inhibitory innervation of pyramidal cells from fast-spiking (FS) interneurons instead of non-FS interneurons is dramatically disrupted by Aβ, and perturbation of the presynaptic inhibitory neurotransmitter gamma-aminobutyric acid (GABA) release underlies this inhibitory input disruption. Finally, we identified the increased dopamine action on dopamine D1 receptor of FS interneurons as a key pathological factor that contributes to GABAergic input perturbation and excitation/inhibition imbalance caused by Aβ. Thus, we conclude that the dopamine receptor 1-dependent disruption of FS GABAergic inhibitory input plays a critical role in Aβ-induced excitation/inhibition imbalance in anterior cingulate cortex.
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Affiliation(s)
- Si-Qiang Ren
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, China.
| | - Wen Yao
- Department of Pharmacology, Wuxi Higher Health Vocational Technology School, Wuxi, China
| | - Jing-Zhi Yan
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical College, Xuzhou, China
| | - Chunhui Jin
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, China
| | - Jia-Jun Yin
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, China
| | - Jianmin Yuan
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, China
| | - Shui Yu
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, China
| | - Zaohuo Cheng
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, China.
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Ma KG, Lv J, Yang WN, Chang KW, Hu XD, Shi LL, Zhai WY, Zong HF, Qian YH. The p38 mitogen activated protein kinase regulates β-amyloid protein internalization through the α7 nicotinic acetylcholine receptor in mouse brain. Brain Res Bull 2017; 137:41-52. [PMID: 29128415 DOI: 10.1016/j.brainresbull.2017.11.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/01/2017] [Accepted: 11/07/2017] [Indexed: 12/29/2022]
Abstract
Alzheimer's disease (AD) is one of the most devastating neurodegenerative disorders. Intracellular β-amyloid protein (Aβ) is an early event in AD. It induces the formation of amyloid plaques and neuron damage. The α7 nicotinic acetylcholine receptor (α7nAChR) has been suggested to play an important role in Aβ caused cognition. It has high affinity with Aβ and could mediate Aβ internalization in vitro. However, whether in mouse brain the p38 MAPK signaling pathway is involved in the regulation of the α7nAChR mediated Aβ internalization and their role in mitochondria remains little known. Therefore, in this study, we revealed that Aβ is internalized by cholinergic and GABAergic neurons. The internalized Aβ were found deposits in lysosomes/endosomes and mitochondria. Aβ could form Aβ-α7nAChR complex with α7nAChR, activates the p38 mitogen activated protein kinase (MAPK). And the increasing of α7nAChR could in return mediate Aβ internalization in the cortex and hippocampus. In addition, by using the α7nAChR agonist PNU282987, the p38 phosphorylation level decreases, rescues the biochemical changes which are tightly associated with Aβ-induced apoptosis, such as Bcl2/Bax level, cytochrome c (Cyt c) release. Collectively, the p38 MAPK signaling pathway could regulate the α7nAChR-mediated internalization of Aβ. The activation of α7nAChR or the inhibition of p38 MAPK signaling pathway may be a beneficial therapy to AD.
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Affiliation(s)
- Kai-Ge Ma
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 76 Yanta West Road, Xi'an, 710061, China
| | - Jia Lv
- Department of Nephrology, First Affiliated Hospital of Xi'an Jiaotong University, 277 Yanta West Road, Xi'an, 710061, China
| | - Wei-Na Yang
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 76 Yanta West Road, Xi'an, 710061, China; Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education of China, Xi'an Jiaotong University Health Science Center, 76 Yanta West Road, Xi'an, 710061, China
| | - Ke-Wei Chang
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 76 Yanta West Road, Xi'an, 710061, China
| | - Xiao-Dan Hu
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 76 Yanta West Road, Xi'an, 710061, China; Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education of China, Xi'an Jiaotong University Health Science Center, 76 Yanta West Road, Xi'an, 710061, China
| | - Li-Li Shi
- Department of Human Anatomy, Xi'an Medical University, 1 Xinwang road, Xi'an, 710021, China
| | - Wan-Ying Zhai
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 76 Yanta West Road, Xi'an, 710061, China
| | - Hang-Fan Zong
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 76 Yanta West Road, Xi'an, 710061, China
| | - Yi-Hua Qian
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 76 Yanta West Road, Xi'an, 710061, China; Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education of China, Xi'an Jiaotong University Health Science Center, 76 Yanta West Road, Xi'an, 710061, China.
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67
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Towards a Better Understanding of GABAergic Remodeling in Alzheimer's Disease. Int J Mol Sci 2017; 18:ijms18081813. [PMID: 28825683 PMCID: PMC5578199 DOI: 10.3390/ijms18081813] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 08/16/2017] [Accepted: 08/17/2017] [Indexed: 12/18/2022] Open
Abstract
γ-aminobutyric acid (GABA) is the primary inhibitory neurotransmitter in the vertebrate brain. In the past, there has been a major research drive focused on the dysfunction of the glutamatergic and cholinergic neurotransmitter systems in Alzheimer’s disease (AD). However, there is now growing evidence in support of a GABAergic contribution to the pathogenesis of this neurodegenerative disease. Previous studies paint a complex, convoluted and often inconsistent picture of AD-associated GABAergic remodeling. Given the importance of the GABAergic system in neuronal function and homeostasis, in the maintenance of the excitatory/inhibitory balance, and in the processes of learning and memory, such changes in GABAergic function could be an important factor in both early and later stages of AD pathogenesis. Given the limited scope of currently available therapies in modifying the course of the disease, a better understanding of GABAergic remodeling in AD could open up innovative and novel therapeutic opportunities.
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68
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Nakada T, Kwee IL, Igarashi H, Suzuki Y. Aquaporin-4 Functionality and Virchow-Robin Space Water Dynamics: Physiological Model for Neurovascular Coupling and Glymphatic Flow. Int J Mol Sci 2017; 18:E1798. [PMID: 28820467 PMCID: PMC5578185 DOI: 10.3390/ijms18081798] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 08/15/2017] [Accepted: 08/16/2017] [Indexed: 11/16/2022] Open
Abstract
The unique properties of brain capillary endothelium, critical in maintaining the blood-brain barrier (BBB) and restricting water permeability across the BBB, have important consequences on fluid hydrodynamics inside the BBB hereto inadequately recognized. Recent studies indicate that the mechanisms underlying brain water dynamics are distinct from systemic tissue water dynamics. Hydrostatic pressure created by the systolic force of the heart, essential for interstitial circulation and lymphatic flow in systemic circulation, is effectively impeded from propagating into the interstitial fluid inside the BBB by the tightly sealed endothelium of brain capillaries. Instead, fluid dynamics inside the BBB is realized by aquaporin-4 (AQP-4), the water channel that connects astrocyte cytoplasm and extracellular (interstitial) fluid. Brain interstitial fluid dynamics, and therefore AQP-4, are now recognized as essential for two unique functions, namely, neurovascular coupling and glymphatic flow, the brain equivalent of systemic lymphatics.
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Affiliation(s)
- Tsutomu Nakada
- Center for Integrated Human Brain Science, Brain Research Institute, University of Niigata, Niigata 951-8585, Japan.
- Department of Neurology, University of California, Davis, VANCHCS, Martinez, CA 94553, USA.
| | - Ingrid L Kwee
- Center for Integrated Human Brain Science, Brain Research Institute, University of Niigata, Niigata 951-8585, Japan.
- Department of Neurology, University of California, Davis, VANCHCS, Martinez, CA 94553, USA.
| | - Hironaka Igarashi
- Center for Integrated Human Brain Science, Brain Research Institute, University of Niigata, Niigata 951-8585, Japan.
| | - Yuji Suzuki
- Center for Integrated Human Brain Science, Brain Research Institute, University of Niigata, Niigata 951-8585, Japan.
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69
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Zhang D, Qi Y, Klyubin I, Ondrejcak T, Sarell CJ, Cuello AC, Collinge J, Rowan MJ. Targeting glutamatergic and cellular prion protein mechanisms of amyloid β-mediated persistent synaptic plasticity disruption: Longitudinal studies. Neuropharmacology 2017; 121:231-246. [PMID: 28390893 DOI: 10.1016/j.neuropharm.2017.03.036] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 03/08/2017] [Accepted: 03/30/2017] [Indexed: 01/09/2023]
Abstract
Alzheimer's disease amyloid-β (Aβ) oligomers are synaptotoxic, inappropriately increasing extracellular glutamate concentration and glutamate receptor activation to thereby rapidly disrupt synaptic plasticity. Thus, acutely promoting brain glutamate homeostasis with a blood-based scavenging system, glutamate-oxaloacetate transaminase (GOT), and blocking metabotropic glutamate 5 (mGlu5) receptor or its co-receptor cellular prion protein (PrP), prevent the acute inhibition of long-term potentiation (LTP) by exogenous Aβ. Here, we evaluated the time course of the effects of such interventions in the persistent disruptive effects of Aβ oligomers, either exogenously injected in wild type rats or endogenously generated in transgenic rats that model Alzheimer's disease amyloidosis. We report that repeated, but not acute, systemic administration of recombinant GOT type 1, with or without the glutamate co-substrate oxaloacetate, reversed the persistent deleterious effect of exogenous Aβ on synaptic plasticity. Moreover, similar repetitive treatment reversibly abrogated the inhibition of LTP monitored longitudinally in freely behaving transgenic rats. Remarkably, brief repeated treatment with an mGlu5 receptor antagonist, basimglurant, or an antibody that prevents Aβ oligomer binding to PrP, ICSM35, also had similar reversible ameliorative effects in the transgenic rat model. Overall, the present findings support the ongoing development of therapeutics for early Alzheimer's disease based on these complementary approaches.
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Affiliation(s)
- Dainan Zhang
- Department of Pharmacology & Therapeutics, and Trinity College Institute of Neuroscience, Trinity College, Dublin 2, Ireland; Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; Center for Neurological Diseases (NCRC-ND), Beijing, China
| | - Yingjie Qi
- Department of Pharmacology & Therapeutics, and Trinity College Institute of Neuroscience, Trinity College, Dublin 2, Ireland.
| | - Igor Klyubin
- Department of Pharmacology & Therapeutics, and Trinity College Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Tomas Ondrejcak
- Department of Pharmacology & Therapeutics, and Trinity College Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Claire J Sarell
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - A Claudio Cuello
- Department of Pharmacology and Therapeutics, Department of Neurology and Neurosurgery, Department of Anatomy and Cell Biology, McGill University, Montreal, Canada
| | - John Collinge
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Michael J Rowan
- Department of Pharmacology & Therapeutics, and Trinity College Institute of Neuroscience, Trinity College, Dublin 2, Ireland.
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70
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Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease, characterized by the loss of memory, multiple cognitive impairments and changes in the personality and behavior. Several decades of intense research have revealed that multiple cellular changes are involved in disease process, including synaptic damage, mitochondrial abnormalities and inflammatory responses, in addition to formation and accumulation of amyloid-β (Aβ) and phosphorylated tau. Although tremendous progress has been made in understanding the impact of neurotransmitters in the progression and pathogenesis of AD, we still do not have a drug molecule associated with neurotransmitter(s) that can delay disease process in elderly individuals and/or restore cognitive functions in AD patients. The purpose of our article is to assess the latest developments in neurotransmitters research using cell and mouse models of AD. We also updated the current status of clinical trials using neurotransmitters' agonists/antagonists in AD.
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Affiliation(s)
- Ramesh Kandimalla
- Garrison Institute on Aging Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Pharmacology & Neuroscience Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - P. Hemachandra Reddy
- Garrison Institute on Aging Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Pharmacology & Neuroscience Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Cell Biology & Biochemistry Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Neurology Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Garrison Institute on Aging, South West Campus, Texas Tech University Health Sciences Center, Lubbock, TX, USA
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71
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Abstract
Although the cause of Alzheimer’s disease (AD) remains unknown, a number of new findings suggest that the immune system may play a critical role in the early stages of the disease. Genome-wide association studies have identified a wide array of risk-associated genes for AD, many of which are associated with abnormal functioning of immune cells. Microglia are the brain’s immune cells. They play an important role in maintaining the brain’s extracellular environment, including clearance of aggregated proteins such as amyloid-β (Aβ). Recent studies suggest that microglia play a more active role in the brain than initially considered. Specifically, microglia provide trophic support to neurons and also regulate synapses. Microglial regulation of neuronal activity may have important consequences for AD. In this article we review the function of microglia in AD and examine the possible relationship between microglial dysfunction and network abnormalities, which occur very early in disease pathogenesis.
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Affiliation(s)
- Katherine A. Southam
- Correspondence to: Dr. Katherine Southam, Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool Street, Hobart, TAS 7000 Australia. Tel.: +61 3 6226 4834; Fax: +61 3 6226 7704; E-mail:
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72
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Zhang D, Jin B, Ondrejcak T, Rowan MJ. Opposite in vivo effects of agents that stimulate or inhibit the glutamate/cysteine exchanger system xc- on the inhibition of hippocampal LTP by Aß. Hippocampus 2016; 26:1655-1665. [PMID: 27701797 DOI: 10.1002/hipo.22667] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/21/2016] [Indexed: 01/17/2023]
Abstract
Aggregated amyloid ß-protein (Aß) is pathognomonic of Alzheimer's disease and certain assemblies of Aß are synaptotoxic. Excess glutamate or diminished glutathione reserve are both implicated in mediating or modulating Aß-induced disruption of synaptic plasticity. The system xc- antiporter promotes Na+ -independent exchange of cystine with glutamate thereby providing a major source of extracellular glutamate and intracellular glutathione concentrations. Here we probed the ability of two drugs with opposite effects on system xc-, the inhibitor sulfasalazine and facilitator N-acetylcysteine, to modulate the ability of Aß1-42 to inhibit long-term potentiation (LTP) in the CA1 area of the anaesthetized rat. Whereas acute systemic treatment with sulfasalazine lowered the threshold for Aß to interfere with synaptic plasticity, N-acetylcysteine prevented the inhibition of LTP by Aß alone or in combination with sulfasalazine. Moreover acute N-acetylcysteine also prevented the inhibition of LTP by TNFα, a putative mediator of Aß actions, and repeated systemic N-acetylcysteine treatment for 7 days reversed the delayed deleterious effect of Aß on LTP. Since both of these drugs are widely used clinically, further evaluation of their potential beneficial and deleterious actions in early Alzheimer's disease seems warranted. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Dainan Zhang
- Department of Pharmacology and Therapeutics, and Trinity College Institute of Neuroscience, Trinity College, Dublin 2, Ireland.,Department of Neurosurgery, the First Affiliated Hospital of Xinxiang Medical University, Weihui, 453100, China
| | - Baozhe Jin
- Department of Neurosurgery, the First Affiliated Hospital of Xinxiang Medical University, Weihui, 453100, China
| | - Tomas Ondrejcak
- Department of Pharmacology and Therapeutics, and Trinity College Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Michael J Rowan
- Department of Pharmacology and Therapeutics, and Trinity College Institute of Neuroscience, Trinity College, Dublin 2, Ireland
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73
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Ju T, Wang X, Zhou S, Zhao T, Yang M, Lin J, Sun L, Liu T, Xu Y, Zhang L. Streptozotocin inhibits synaptic transmission and edaravone attenuates streptozotocin-induced electrophysiological changes in CA1 pyramidal neurons of rat hippocampal slices. Neurotoxicology 2016; 57:75-86. [PMID: 27637609 DOI: 10.1016/j.neuro.2016.09.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 08/05/2016] [Accepted: 09/10/2016] [Indexed: 02/01/2023]
Abstract
The purpose of this study was to investigate the acute and chronic effects of streptozotocin (STZ) upon synaptic transmission and the effects of edaravone (EDA, a free radical scavenger) on STZ-induced electrophysiological changes in CA1 pyramidal neurons of rat hippocampal slices. To accomplish this goal, spontaneous excitatory postsynaptic current (sEPSC), miniature excitatory postsynaptic current (mEPSC), spontaneous inhibitory postsynaptic current (sIPSC) and miniature inhibitory postsynaptic current (mIPSC) were recorded within hippocampal slices using whole-cell patch clamp techniques. The results showed that the amplitudes and frequencies of sEPSC, mEPSC, sIPSC and mIPSC were inhibited by 1000μM STZ, while treatment of EDA (1000μM) attenuated these STZ-induced changes. The degree of these neurotoxic effects of STZ and effects of EDA increased as a function of drug duration as assessed at 2, 4 or 8h of exposure. Taken together, our results demonstrate that STZ induces neurotoxicity within these hippocampal slices through its capacity to alter synaptic transmission and these STZ-induced alterations in electrophysiological responses are attenuated by EDA.
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Affiliation(s)
- Ting Ju
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, 23 Post Street, Harbin 150001, PR China.
| | - Xiaoran Wang
- Department of Physiology, Harbin Medical University, PR China.
| | - Shanshan Zhou
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, 23 Post Street, Harbin 150001, PR China.
| | - Tingting Zhao
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, 23 Post Street, Harbin 150001, PR China.
| | - Meimei Yang
- Department of Neurology, The Fourth Affiliated Hospital of Harbin Medical University, PR China.
| | - Jinghan Lin
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, 23 Post Street, Harbin 150001, PR China.
| | - Lina Sun
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, 23 Post Street, Harbin 150001, PR China.
| | - Tingjiao Liu
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, 23 Post Street, Harbin 150001, PR China.
| | - Yi Xu
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, 23 Post Street, Harbin 150001, PR China.
| | - Liming Zhang
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, 23 Post Street, Harbin 150001, PR China.
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Mander BA, Winer JR, Jagust WJ, Walker MP. Sleep: A Novel Mechanistic Pathway, Biomarker, and Treatment Target in the Pathology of Alzheimer's Disease? Trends Neurosci 2016; 39:552-566. [PMID: 27325209 PMCID: PMC4967375 DOI: 10.1016/j.tins.2016.05.002] [Citation(s) in RCA: 283] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 04/13/2016] [Accepted: 05/10/2016] [Indexed: 12/16/2022]
Abstract
Sleep disruption appears to be a core component of Alzheimer's disease (AD) and its pathophysiology. Signature abnormalities of sleep emerge before clinical onset of AD. Moreover, insufficient sleep facilitates accumulation of amyloid-β (Aβ), potentially triggering earlier cognitive decline and conversion to AD. Building on such findings, this review has four goals: evaluating (i) associations and plausible mechanisms linking non-rapid-eye-movement (NREM) sleep disruption, Aβ, and AD; (ii) a role for NREM sleep disruption as a novel factor linking cortical Aβ to impaired hippocampus-dependent memory consolidation; (iii) the potential diagnostic utility of NREM sleep disruption as a new biomarker of AD; and (iv) the possibility of sleep as a new treatment target in aging, affording preventative and therapeutic benefits.
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Affiliation(s)
- Bryce A Mander
- Sleep and Neuroimaging Laboratory University of California, Berkeley, CA 94720-1650, USA.
| | - Joseph R Winer
- Sleep and Neuroimaging Laboratory University of California, Berkeley, CA 94720-1650, USA
| | - William J Jagust
- Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720-1650, USA; Molecular Biophysics and Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Matthew P Walker
- Sleep and Neuroimaging Laboratory University of California, Berkeley, CA 94720-1650, USA; Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720-1650, USA.
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Yan R, Fan Q, Zhou J, Vassar R. Inhibiting BACE1 to reverse synaptic dysfunctions in Alzheimer's disease. Neurosci Biobehav Rev 2016; 65:326-40. [PMID: 27044452 PMCID: PMC4856578 DOI: 10.1016/j.neubiorev.2016.03.025] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 03/25/2016] [Accepted: 03/29/2016] [Indexed: 12/21/2022]
Abstract
Over the past two decades, many studies have identified significant contributions of toxic β-amyloid peptides (Aβ) to the etiology of Alzheimer's disease (AD), which is the most common age-dependent neurodegenerative disease. AD is also recognized as a disease of synaptic failure. Aβ, generated by sequential proteolytic cleavages of amyloid precursor protein (APP) by BACE1 and γ-secretase, is one of major culprits that cause this failure. In this review, we summarize current findings on how BACE1-cleaved APP products impact learning and memory through proteins localized on glutamatergic, GABAergic, and dopaminergic synapses. Considering the broad effects of Aβ on all three types of synapses, BACE1 inhibition emerges as a practical approach for ameliorating Aβ-mediated synaptic dysfunctions. Since BACE1 inhibitory drugs are currently in clinical trials, this review also discusses potential complications arising from BACE1 inhibition. We emphasize that the benefits of BACE1 inhibitory drugs will outweigh the concerns.
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Affiliation(s)
- Riqiang Yan
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
| | - Qingyuan Fan
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - John Zhou
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Robert Vassar
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
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Diabetes and Alzheimer’s disease crosstalk. Neurosci Biobehav Rev 2016; 64:272-87. [DOI: 10.1016/j.neubiorev.2016.03.005] [Citation(s) in RCA: 122] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 01/26/2016] [Accepted: 03/04/2016] [Indexed: 12/12/2022]
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Maatuf Y, Stern EA, Slovin H. Abnormal Population Responses in the Somatosensory Cortex of Alzheimer's Disease Model Mice. Sci Rep 2016; 6:24560. [PMID: 27079783 PMCID: PMC4832196 DOI: 10.1038/srep24560] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 03/31/2016] [Indexed: 01/04/2023] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia. One of the neuropathological hallmarks of AD is the accumulation of amyloid-β plaques. Overexpression of human amyloid precursor protein in transgenic mice induces hippocampal and neocortical amyloid-β accumulation and plaque deposition that increases with age. The impact of these effects on neuronal population responses and network activity in sensory cortex is not well understood. We used Voltage Sensitive Dye Imaging, to investigate at high spatial and temporal resolution, the sensory evoked population responses in the barrel cortex of aged transgenic (Tg) mice and of age-matched non-transgenic littermate controls (Ctrl) mice. We found that a whisker deflection evoked abnormal sensory responses in the barrel cortex of Tg mice. The response amplitude and the spatial spread of the cortical responses were significantly larger in Tg than in Ctrl mice. At the network level, spontaneous activity was less synchronized over cortical space than in Ctrl mice, however synchronization during evoked responses induced by whisker deflection did not differ between the two groups. Thus, the presence of elevated Aβ and plaques may alter population responses and disrupts neural synchronization in large-scale networks, leading to abnormalities in sensory processing.
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Affiliation(s)
- Yossi Maatuf
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002 Israel
| | - Edward A Stern
- The Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, 5290002 Israel.,MassGeneral Institute of Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA
| | - Hamutal Slovin
- The Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, 5290002 Israel
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Neuroprotective Effect of Fisetin Against Amyloid-Beta-Induced Cognitive/Synaptic Dysfunction, Neuroinflammation, and Neurodegeneration in Adult Mice. Mol Neurobiol 2016; 54:2269-2285. [DOI: 10.1007/s12035-016-9795-4] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 02/11/2016] [Indexed: 12/22/2022]
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Zhou X, Li Y, Shi X, Ma C. An overview on therapeutics attenuating amyloid β level in Alzheimer's disease: targeting neurotransmission, inflammation, oxidative stress and enhanced cholesterol levels. Am J Transl Res 2016; 8:246-69. [PMID: 27158324 PMCID: PMC4846881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 11/26/2015] [Indexed: 06/05/2023]
Abstract
Alzheimer's disease (AD) is the most common underlying cause of dementia, and novel drugs for its treatment are needed. Of the different theories explaining the development and progression of AD, "amyloid hypothesis" is the most supported by experimental data. This hypothesis states that the cleavage of amyloid precursor protein (APP) leads to the formation of amyloid beta (Aβ) peptides that congregate with formation and deposition of Aβ plaques in the frontal cortex and hippocampus. Risk factors including neurotransmitter modulation, chronic inflammation, metal-induced oxidative stress and elevated cholesterol levels are key contributors to the disease progress. Current therapeutic strategies abating AD progression are primarily based on anti-acetylcholinesterase (AChE) inhibitors as cognitive enhancers. The AChE inhibitor, donepezil, is proven to strengthen cognitive functions and appears effective in treating moderate to severe AD patients. N-Methyl-D-aspartate receptor antagonist, memantine, is also useful, and its combination with donepezil demonstrated a strong stabilizing effect in clinical studies on AD. Nonsteroidal anti-inflammatory drugs delayed the onset and progression of AD and attenuated cognitive dysfunction. Based upon epidemiological evidence and animal studies, antioxidants emerged as potential AD preventive agents; however, clinical trials revealed inconsistencies. Pharmacokinetic and pharmacodynamic profiling demonstrated pleiotropic functions of the hypolipidemic class of drugs, statins, potentially contributing towards the prevention of AD. In addition, targeting the APP processing pathways, stimulating neuroprotective signaling mechanisms, using the amyloid anti-aggregants and Aβ immunotherapy surfaced as well-tested strategies in reducing the AD-like pathology. Overall, this review covers mechanism of inducing the Aβ formation, key risk factors and major therapeutics prevalent in the AD treatment nowadays. It also delineates the need for novel screening approaches towards identifying drugs that may prevent or at least limit the progression of this devastating disease.
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Affiliation(s)
- Xiaoling Zhou
- The Affiliated Hospital to Changchun University of Chinese Medicine Changchun, China
| | - Yifei Li
- The Affiliated Hospital to Changchun University of Chinese Medicine Changchun, China
| | - Xiaozhe Shi
- The Affiliated Hospital to Changchun University of Chinese Medicine Changchun, China
| | - Chun Ma
- The Affiliated Hospital to Changchun University of Chinese Medicine Changchun, China
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