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Chen AM, Gajdošík M, Ahmed W, Ahn S, Babb JS, Blessing EM, Boutajangout A, de Leon MJ, Debure L, Gaggi N, Gajdošík M, George A, Ghuman M, Glodzik L, Harvey P, Juchem C, Marsh K, Peralta R, Rusinek H, Sheriff S, Vedvyas A, Wisniewski T, Zheng H, Osorio R, Kirov II. Retrospective analysis of Braak stage- and APOE4 allele-dependent associations between MR spectroscopy and markers of tau and neurodegeneration in cognitively unimpaired elderly. Neuroimage 2024; 297:120742. [PMID: 39029606 DOI: 10.1016/j.neuroimage.2024.120742] [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: 03/11/2024] [Revised: 06/28/2024] [Accepted: 07/16/2024] [Indexed: 07/21/2024] Open
Abstract
PURPOSE The pathological hallmarks of Alzheimer's disease (AD), amyloid, tau, and associated neurodegeneration, are present in the cortical gray matter (GM) years before symptom onset, and at significantly greater levels in carriers of the apolipoprotein E4 (APOE4) allele. Their respective biomarkers, A/T/N, have been found to correlate with aspects of brain biochemistry, measured with magnetic resonance spectroscopy (MRS), indicating a potential for MRS to augment the A/T/N framework for staging and prediction of AD. Unfortunately, the relationships between MRS and A/T/N biomarkers are unclear, largely due to a lack of studies examining them in the context of the spatial and temporal model of T/N progression. Advanced MRS acquisition and post-processing approaches have enabled us to address this knowledge gap and test the hypotheses, that glutamate-plus-glutamine (Glx) and N-acetyl-aspartate (NAA), metabolites reflecting synaptic and neuronal health, respectively, measured from regions on the Braak stage continuum, correlate with: (i) cerebrospinal fluid (CSF) p-tau181 level (T), and (ii) hippocampal volume or cortical thickness of parietal lobe GM (N). We hypothesized that these correlations will be moderated by Braak stage and APOE4 genotype. METHODS We conducted a retrospective imaging study of 34 cognitively unimpaired elderly individuals who received APOE4 genotyping and lumbar puncture from pre-existing prospective studies at the NYU Grossman School of Medicine between October 2014 and January 2019. Subjects returned for their imaging exam between April 2018 and February 2020. Metabolites were measured from the left hippocampus (Braak II) using a single-voxel semi-adiabatic localization by adiabatic selective refocusing sequence; and from the bilateral posterior cingulate cortex (PCC; Braak IV), bilateral precuneus (Braak V), and bilateral precentral gyrus (Braak VI) using a multi-voxel echo-planar spectroscopic imaging sequence. Pearson and Spearman correlations were used to examine the relationships between absolute levels of choline, creatine, myo-inositol, Glx, and NAA and CSF p-tau181, and between these metabolites and hippocampal volume or parietal cortical thicknesses. Covariates included age, sex, years of education, Fazekas score, and months between CSF collection and MRI exam. RESULTS There was a direct correlation between hippocampal Glx and CSF p-tau181 in APOE4 carriers (Pearson's r = 0.76, p = 0.02), but not after adjusting for covariates. In the entire cohort, there was a direct correlation between hippocampal NAA and hippocampal volume (Spearman's r = 0.55, p = 0.001), even after adjusting for age and Fazekas score (Spearman's r = 0.48, p = 0.006). This relationship was observed only in APOE4 carriers (Pearson's r = 0.66, p = 0.017), and was also retained after adjustment (Pearson's r = 0.76, p = 0.008; metabolite-by-carrier interaction p = 0.03). There were no findings in the PCC, nor in the negative control (late Braak stage) regions of the precuneus and precentral gyrus. CONCLUSIONS Our findings are in line with the spatially- and temporally-resolved Braak staging model of pathological severity in which the hippocampus is affected earlier than the PCC. The correlations, between MRS markers of synaptic and neuronal health and, respectively, T and N pathology, were found exclusively within APOE4 carriers, suggesting a connection with AD pathological change, rather than with normal aging. We therefore conclude that MRS has the potential to augment early A/T/N staging, with the hippocampus serving as a more sensitive MRS target compared to the PCC.
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Affiliation(s)
- Anna M Chen
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Center for Advanced Imaging Innovation and Research (CAI(2)R), Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Vilcek Institute of Graduate Biomedical Sciences, NYU Grossman School of Medicine, New York, NY, USA
| | - Martin Gajdošík
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Center for Advanced Imaging Innovation and Research (CAI(2)R), Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Department of Biomedical Engineering, Columbia University, New York, NY, USA
| | - Wajiha Ahmed
- Center for Cognitive Neurology, Department of Neurology, NYU Grossman School of Medicine, New York, NY, USA
| | - Sinyeob Ahn
- Siemens Medical Solutions USA Inc., Malvern, PA, USA
| | - James S Babb
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Center for Advanced Imaging Innovation and Research (CAI(2)R), Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Esther M Blessing
- Department of Psychiatry, NYU Grossman School of Medicine, New York, NY, USA; Healthy Brain Aging and Sleep Center, NYU Langone Health, New York, NY, USA
| | - Allal Boutajangout
- Center for Cognitive Neurology, Department of Neurology, NYU Grossman School of Medicine, New York, NY, USA; Department of Neuroscience and Physiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Mony J de Leon
- Retired Director, Center for Brain Health, Department of Psychiatry, NYU Grossman School of Medicine, New York, NY, USA; Brain Health Imaging Institute, Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | - Ludovic Debure
- Center for Cognitive Neurology, Department of Neurology, NYU Grossman School of Medicine, New York, NY, USA
| | - Naomi Gaggi
- Department of Psychiatry, NYU Grossman School of Medicine, New York, NY, USA; Healthy Brain Aging and Sleep Center, NYU Langone Health, New York, NY, USA
| | - Mia Gajdošík
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Center for Advanced Imaging Innovation and Research (CAI(2)R), Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Ajax George
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Center for Advanced Imaging Innovation and Research (CAI(2)R), Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Mobeena Ghuman
- Center for Cognitive Neurology, Department of Neurology, NYU Grossman School of Medicine, New York, NY, USA
| | - Lidia Glodzik
- Brain Health Imaging Institute, Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | - Patrick Harvey
- Brain Health Imaging Institute, Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | - Christoph Juchem
- Department of Biomedical Engineering, Columbia University, New York, NY, USA; Department of Radiology, Columbia University, New York, NY, USA
| | - Karyn Marsh
- Center for Cognitive Neurology, Department of Neurology, NYU Grossman School of Medicine, New York, NY, USA
| | - Rosemary Peralta
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Center for Advanced Imaging Innovation and Research (CAI(2)R), Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Henry Rusinek
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Center for Advanced Imaging Innovation and Research (CAI(2)R), Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Sulaiman Sheriff
- Department of Radiology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Alok Vedvyas
- Center for Cognitive Neurology, Department of Neurology, NYU Grossman School of Medicine, New York, NY, USA
| | - Thomas Wisniewski
- Center for Cognitive Neurology, Department of Neurology, NYU Grossman School of Medicine, New York, NY, USA; Department of Psychiatry, NYU Grossman School of Medicine, New York, NY, USA; Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Helena Zheng
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Center for Advanced Imaging Innovation and Research (CAI(2)R), Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA
| | - Ricardo Osorio
- Department of Psychiatry, NYU Grossman School of Medicine, New York, NY, USA; Healthy Brain Aging and Sleep Center, NYU Langone Health, New York, NY, USA.
| | - Ivan I Kirov
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Center for Advanced Imaging Innovation and Research (CAI(2)R), Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA; Vilcek Institute of Graduate Biomedical Sciences, NYU Grossman School of Medicine, New York, NY, USA; Center for Cognitive Neurology, Department of Neurology, NYU Grossman School of Medicine, New York, NY, USA; Department of Neurology, NYU Grossman School of Medicine, New York, NY, USA.
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Soares C, Da Ros LU, Machado LS, Rocha A, Lazzarotto G, Carello-Collar G, De Bastiani MA, Ferrari-Souza JP, Lussier FZ, Souza DO, Rosa-Neto P, Pascoal TA, Bellaver B, Zimmer ER. The glutamatergic system in Alzheimer's disease: a systematic review with meta-analysis. Mol Psychiatry 2024:10.1038/s41380-024-02473-0. [PMID: 38366114 DOI: 10.1038/s41380-024-02473-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 01/23/2024] [Accepted: 01/31/2024] [Indexed: 02/18/2024]
Abstract
Glutamatergic neurotransmission system dysregulation may play an important role in the pathophysiology of Alzheimer's disease (AD). However, reported results on glutamatergic components across brain regions are contradictory. Here, we conducted a systematic review with meta-analysis to examine whether there are consistent glutamatergic abnormalities in the human AD brain. We searched PubMed and Web of Science (database origin-October 2023) reports evaluating glutamate, glutamine, glutaminase, glutamine synthetase, glutamate reuptake, aspartate, excitatory amino acid transporters, vesicular glutamate transporters, glycine, D-serine, metabotropic and ionotropic glutamate receptors in the AD human brain (PROSPERO #CDRD42022299518). The studies were synthesized by outcome and brain region. We included cortical regions, the whole brain (cortical and subcortical regions combined), the entorhinal cortex and the hippocampus. Pooled effect sizes were determined with standardized mean differences (SMD), random effects adjusted by false discovery rate, and heterogeneity was examined by I2 statistics. The search retrieved 6 936 articles, 63 meeting the inclusion criteria (N = 709CN/786AD; mean age 75/79). We showed that the brain of AD individuals presents decreased glutamate (SMD = -0.82; I2 = 74.54%; P < 0.001) and aspartate levels (SMD = -0.64; I2 = 89.71%; P = 0.006), and reuptake (SMD = -0.75; I2 = 83.04%; P < 0.001. We also found reduced α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPAR)-GluA2/3 levels (SMD = -0.63; I2 = 95.55%; P = 0.046), hypofunctional N-methyl-D-aspartate receptor (NMDAR) (SMD = -0.60; I2 = 91.47%; P < 0.001) and selective reduction of NMDAR-GluN2B subunit levels (SMD = -1.07; I2 = 41.81%; P < 0.001). Regional differences include lower glutamate levels in cortical areas and aspartate levels in cortical areas and in the hippocampus, reduced glutamate reuptake, reduced AMPAR-GluA2/3 in the entorhinal cortex, hypofunction of NMDAR in cortical areas, and a decrease in NMDAR-GluN2B subunit levels in the entorhinal cortex and hippocampus. Other parameters studied were not altered. Our findings show depletion of the glutamatergic system and emphasize the importance of understanding glutamate-mediated neurotoxicity in AD. This study has implications for the development of therapies and biomarkers in AD.
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Affiliation(s)
- Carolina Soares
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Lucas Uglione Da Ros
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Luiza Santos Machado
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Andreia Rocha
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Gabriela Lazzarotto
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Giovanna Carello-Collar
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Marco A De Bastiani
- Graduate Program in Biological Sciences: Pharmacology and Therapeutics, UFRGS, Porto Alegre, Brazil
| | - João Pedro Ferrari-Souza
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Firoza Z Lussier
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Diogo O Souza
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Biochemistry, UFRGS, Porto Alegre, Brazil
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, McGill University, Montreal, QC, Canada
- Douglas Research Institute, Le Centre Intégré Universitaire de Santé et de Services Sociaux de l'Ouest-de-l'Île-de-Montréal, McGill University, Montreal, QC, Canada
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- Department of Psychiatry, McGill University, Montreal, QC, Canada
| | - Tharick A Pascoal
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Bruna Bellaver
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Eduardo R Zimmer
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
- Graduate Program in Biological Sciences: Pharmacology and Therapeutics, UFRGS, Porto Alegre, Brazil.
- Department of Biochemistry, UFRGS, Porto Alegre, Brazil.
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.
- Brain Institute of Rio Grande do Sul - Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.
- Department of Pharmacology, UFRGS, Porto Alegre, Brazil.
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Ma J, Hu Z, Yue H, Luo Y, Wang C, Wu X, Gu Y, Wang L. GRM2 Regulates Functional Integration of Adult-Born DGCs by Paradoxically Modulating MEK/ERK1/2 Pathway. J Neurosci 2023; 43:2822-2836. [PMID: 36878727 PMCID: PMC10124958 DOI: 10.1523/jneurosci.1886-22.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 02/01/2023] [Accepted: 02/19/2023] [Indexed: 03/08/2023] Open
Abstract
Metabotropic glutamate receptor 2 (GRM2) is highly expressed in hippocampal dentate granule cells (DGCs), regulating synaptic transmission and hippocampal functions. Newborn DGCs are continuously generated throughout life and express GRM2 when they are mature. However, it remained unclear whether and how GRM2 regulates the development and integration of these newborn neurons. We discovered that the expression of GRM2 in adult-born DGCs increased with neuronal development in mice of both sexes. Lack of GRM2 caused developmental defects of DGCs and impaired hippocampus-dependent cognitive functions. Intriguingly, our data showed that knockdown of Grm2 resulted in decreased b/c-Raf kinases and paradoxically led to an excessive activation of MEK/ERK1/2 pathway. Inhibition of MEK ameliorated the developmental defects caused by Grm2 knockdown. Together, our results indicate that GRM2 is necessary for the development and functional integration of newborn DGCs in the adult hippocampus through regulating the phosphorylation and activation state of MEK/ERK1/2 pathway.SIGNIFICANCE STATEMENT Metabotropic glutamate receptor 2 (GRM2) is highly expressed in mature dentate granule cells (DGCs) in the hippocampus. It remains unclear whether GRM2 is required for the development and integration of adult-born DGCs. We provided in vivo and in vitro evidence to show that GRM2 regulates the development of adult-born DGCs and their integration into existing hippocampal circuits. Lack of GRM2 in a cohort of newborn DGCs impaired object-to-location memory in mice. Moreover, we revealed that GRM2 knockdown paradoxically upregulated MEK/ERK1/2 pathway by suppressing b/c-Raf in developing neurons, which is likely a common mechanism underlying the regulation of the development of neurons expressing GRM2. Thus, Raf/MEK/ERK1/2 pathway could be a potential target for brain diseases related to GRM2 abnormality.
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Affiliation(s)
- Jiao Ma
- Department of Neurology of the First Affiliated Hospital, Interdisciplinary Institute of Neuroscience and Technology, Zhejiang University School of Medicine, 310027 Hangzhou, People's Republic of China
- Center of Stem Cell and Regenerative Medicine, and Department of Neurology of the Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, 310058 Hangzhou, People's Republic of China
| | - Zhechun Hu
- School of Brain Science and Brain Medicine, Zhejiang University, 310058 Hangzhou, People's Republic of China
| | - Huimin Yue
- Department of Neurology of the First Affiliated Hospital, Interdisciplinary Institute of Neuroscience and Technology, Zhejiang University School of Medicine, 310027 Hangzhou, People's Republic of China
- School of Brain Science and Brain Medicine, Zhejiang University, 310058 Hangzhou, People's Republic of China
| | - Yujian Luo
- Department of Neurology of the First Affiliated Hospital, Interdisciplinary Institute of Neuroscience and Technology, Zhejiang University School of Medicine, 310027 Hangzhou, People's Republic of China
- School of Brain Science and Brain Medicine, Zhejiang University, 310058 Hangzhou, People's Republic of China
| | - Chao Wang
- School of Brain Science and Brain Medicine, Zhejiang University, 310058 Hangzhou, People's Republic of China
| | - Xuan Wu
- Center of Stem Cell and Regenerative Medicine, and Department of Neurology of the Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, 310058 Hangzhou, People's Republic of China
| | - Yan Gu
- Center of Stem Cell and Regenerative Medicine, and Department of Neurology of the Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, 310058 Hangzhou, People's Republic of China
- MOE Frontier Science Center for Brain Science and Brain-Machine Integration, Zhejiang University, 310058 Hangzhou, People's Republic of China
| | - Lang Wang
- Department of Neurology of the First Affiliated Hospital, Interdisciplinary Institute of Neuroscience and Technology, Zhejiang University School of Medicine, 310027 Hangzhou, People's Republic of China
- School of Brain Science and Brain Medicine, Zhejiang University, 310058 Hangzhou, People's Republic of China
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Griffiths J, Grant SGN. Synapse pathology in Alzheimer's disease. Semin Cell Dev Biol 2023; 139:13-23. [PMID: 35690535 DOI: 10.1016/j.semcdb.2022.05.028] [Citation(s) in RCA: 26] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/12/2022] [Accepted: 05/27/2022] [Indexed: 12/31/2022]
Abstract
Synapse loss and damage are central features of Alzheimer's disease (AD) and contribute to the onset and progression of its behavioural and physiological features. Here we review the literature describing synapse pathology in AD, from what we have learned from microscopy in terms of its impacts on synapse architecture, to the mechanistic role of Aβ, tau and glial cells, mitochondrial dysfunction, and the link with AD risk genes. We consider the emerging view that synapse pathology may operate at a further level, that of synapse diversity, and discuss the prospects for leveraging new synaptome mapping methods to comprehensively understand the molecular properties of vulnerable and resilient synapses. Uncovering AD impacts on brain synapse diversity should inform therapeutic approaches targeted at preserving or replenishing lost and damaged synapses and aid the interpretation of clinical imaging approaches that aim to measure synapse damage.
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Affiliation(s)
- Jessica Griffiths
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK; Dementia Research Institute at Imperial College, Department of Brain Sciences, Imperial College London, London W12 0NN, UK
| | - Seth G N Grant
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK.
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Holter KM, Pierce BE, Gould RW. Metabotropic glutamate receptor function and regulation of sleep-wake cycles. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 168:93-175. [PMID: 36868636 DOI: 10.1016/bs.irn.2022.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Metabotropic glutamate (mGlu) receptors are the most abundant family of G-protein coupled receptors and are widely expressed throughout the central nervous system (CNS). Alterations in glutamate homeostasis, including dysregulations in mGlu receptor function, have been indicated as key contributors to multiple CNS disorders. Fluctuations in mGlu receptor expression and function also occur across diurnal sleep-wake cycles. Sleep disturbances including insomnia are frequently comorbid with neuropsychiatric, neurodevelopmental, and neurodegenerative conditions. These often precede behavioral symptoms and/or correlate with symptom severity and relapse. Chronic sleep disturbances may also be a consequence of primary symptom progression and can exacerbate neurodegeneration in disorders including Alzheimer's disease (AD). Thus, there is a bidirectional relationship between sleep disturbances and CNS disorders; disrupted sleep may serve as both a cause and a consequence of the disorder. Importantly, comorbid sleep disturbances are rarely a direct target of primary pharmacological treatments for neuropsychiatric disorders even though improving sleep can positively impact other symptom clusters. This chapter details known roles of mGlu receptor subtypes in both sleep-wake regulation and CNS disorders focusing on schizophrenia, major depressive disorder, post-traumatic stress disorder, AD, and substance use disorder (cocaine and opioid). In this chapter, preclinical electrophysiological, genetic, and pharmacological studies are described, and, when possible, human genetic, imaging, and post-mortem studies are also discussed. In addition to reviewing the important relationships between sleep, mGlu receptors, and CNS disorders, this chapter highlights the development of selective mGlu receptor ligands that hold promise for improving both primary symptoms and sleep disturbances.
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Affiliation(s)
- Kimberly M Holter
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Bethany E Pierce
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Robert W Gould
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States.
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Li SH, Abd-Elrahman KS, Ferguson SS. Targeting mGluR2/3 for treatment of neurodegenerative and neuropsychiatric diseases. Pharmacol Ther 2022; 239:108275. [DOI: 10.1016/j.pharmthera.2022.108275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 08/23/2022] [Accepted: 08/23/2022] [Indexed: 10/15/2022]
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Cox MF, Hascup ER, Bartke A, Hascup KN. Friend or Foe? Defining the Role of Glutamate in Aging and Alzheimer’s Disease. FRONTIERS IN AGING 2022; 3:929474. [PMID: 35821835 PMCID: PMC9261322 DOI: 10.3389/fragi.2022.929474] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 05/17/2022] [Indexed: 11/13/2022]
Abstract
Aging is a naturally occurring decline of physiological processes and biological pathways that affects both the structural and functional integrity of the body and brain. These physiological changes reduce motor skills, executive function, memory recall, and processing speeds. Aging is also a major risk factor for multiple neurodegenerative disorders including Alzheimer’s disease (AD). Identifying a biomarker, or biomarkers, that signals the transition from physiological to pathological aging would aid in earlier therapeutic options or interventional strategies. Considering the importance of glutamate signaling in synaptic plasticity, motor movement, and cognition, this neurotransmitter serves as a juncture between cognitive health and disease. This article discusses glutamatergic signaling during physiological aging and the pathological changes observed in AD patients. Findings from studies in mouse models of successful aging and AD are reviewed and provide a biological context for this transition. Finally, current techniques to monitor brain glutamate are highlighted. These techniques may aid in elucidating time-point specific therapeutic windows to modify disease outcome.
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Affiliation(s)
- MaKayla F. Cox
- Dale and Deborah Smith Center for Alzheimer’s Research and Treatment, Department of Neurology, Neurosciences Institute, Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Erin R. Hascup
- Dale and Deborah Smith Center for Alzheimer’s Research and Treatment, Department of Neurology, Neurosciences Institute, Southern Illinois University School of Medicine, Springfield, IL, United States
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Andrzej Bartke
- Dale and Deborah Smith Center for Alzheimer’s Research and Treatment, Department of Neurology, Neurosciences Institute, Southern Illinois University School of Medicine, Springfield, IL, United States
- Department of Internal Medicine, Southern Illinois University School of Medicine, Springfield, IL, United States
- Department of Medical Microbiology, Immunology and Cell Biology, Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Kevin N. Hascup
- Dale and Deborah Smith Center for Alzheimer’s Research and Treatment, Department of Neurology, Neurosciences Institute, Southern Illinois University School of Medicine, Springfield, IL, United States
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, United States
- Department of Medical Microbiology, Immunology and Cell Biology, Southern Illinois University School of Medicine, Springfield, IL, United States
- *Correspondence: Kevin N. Hascup,
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Cao L, Kong Y, Ji B, Ren Y, Guan Y, Ni R. Positron Emission Tomography in Animal Models of Tauopathies. Front Aging Neurosci 2022; 13:761913. [PMID: 35082657 PMCID: PMC8784812 DOI: 10.3389/fnagi.2021.761913] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 11/30/2021] [Indexed: 12/18/2022] Open
Abstract
The microtubule-associated protein tau (MAPT) plays an important role in Alzheimer's disease and primary tauopathy diseases. The abnormal accumulation of tau contributes to the development of neurotoxicity, inflammation, neurodegeneration, and cognitive deficits in tauopathy diseases. Tau synergically interacts with amyloid-beta in Alzheimer's disease leading to detrimental consequence. Thus, tau has been an important target for therapeutics development for Alzheimer's disease and primary tauopathy diseases. Tauopathy animal models recapitulating the tauopathy such as transgenic, knock-in mouse and rat models have been developed and greatly facilitated the understanding of disease mechanisms. The advance in PET and imaging tracers have enabled non-invasive detection of the accumulation and spread of tau, the associated microglia activation, metabolic, and neurotransmitter receptor alterations in disease animal models. In vivo microPET studies on mouse or rat models of tauopathy have provided significant insights into the phenotypes and time course of pathophysiology of these models and allowed the monitoring of treatment targeting at tau. In this study, we discuss the utilities of PET and recently developed tracers for evaluating the pathophysiology in tauopathy animal models. We point out the outstanding challenges and propose future outlook in visualizing tau-related pathophysiological changes in brain of tauopathy disease animal models.
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Affiliation(s)
- Lei Cao
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
- Changes Technology Corporation Ltd., Shanghai, China
| | - Yanyan Kong
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Bin Ji
- Department of Radiopharmacy and Molecular Imaging, School of Pharmacy, Fudan University, Shanghai, China
| | - Yutong Ren
- Guangdong Robotics Association, Guangzhou, China
| | - Yihui Guan
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Ruiqing Ni
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
- Institute for Biomedical Engineering, ETH Zurich and University of Zurich, Zurich, Switzerland
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9
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Elevated hippocampal mGlut2 receptors in rats with metabolic syndrome-induced-memory impairment, possible protection by vitamin D. Brain Res Bull 2022; 180:108-117. [DOI: 10.1016/j.brainresbull.2022.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 12/21/2021] [Accepted: 01/05/2022] [Indexed: 12/29/2022]
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10
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Woo JA, Yan Y, Kee TR, Cazzaro S, McGill Percy KC, Wang X, Liu T, Liggett SB, Kang DE. β-arrestin1 promotes tauopathy by transducing GPCR signaling, disrupting microtubules and autophagy. Life Sci Alliance 2021; 5:5/3/e202101183. [PMID: 34862271 PMCID: PMC8675912 DOI: 10.26508/lsa.202101183] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 11/18/2021] [Accepted: 11/19/2021] [Indexed: 01/14/2023] Open
Abstract
GPCRs regulator, β-arrestin1, is increased in FTLD-tau patients, is required for β2-adrenergic receptor and metabotropic glutamate receptor 2-induced tau phosphorylation, promotes tau aggregation by impairing autophagy, and destabilizes microtubule dynamics, whereas genetic reduction in β-arrestin1 mitigates tauopathy and cognitive impairments. G protein–coupled receptors (GPCRs) have been shown to play integral roles in Alzheimer’s disease pathogenesis. However, it is unclear how diverse GPCRs similarly affect Aβ and tau pathogenesis. GPCRs share a common mechanism of action via the β-arrestin scaffolding signaling complexes, which not only serve to desensitize GPCRs by internalization, but also mediate multiple downstream signaling events. As signaling via the GPCRs, β2-adrenergic receptor (β2AR), and metabotropic glutamate receptor 2 (mGluR2) promotes hyperphosphorylation of tau, we hypothesized that β-arrestin1 represents a point of convergence for such pathogenic activities. Here, we report that β-arrestins are not only essential for β2AR and mGluR2-mediated increase in pathogenic tau but also show that β-arrestin1 levels are increased in brains of Frontotemporal lobar degeneration (FTLD-tau) patients. Increased β-arrestin1 in turn drives the accumulation of pathogenic tau, whereas reduced ARRB1 alleviates tauopathy and rescues impaired synaptic plasticity and cognitive impairments in PS19 mice. Biochemical and cellular studies show that β-arrestin1 drives tauopathy by destabilizing microtubules and impeding p62/SQSTM1 autophagy flux by interfering with p62 body formation, which promotes pathogenic tau accumulation.
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Affiliation(s)
- Jung-Aa Woo
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH, USA
| | - Yan Yan
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH, USA.,Department of Molecular Medicine, University of South Florida, College of Medicine, Tampa, FL, USA
| | - Teresa R Kee
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH, USA.,Department of Molecular Medicine, University of South Florida, College of Medicine, Tampa, FL, USA
| | - Sara Cazzaro
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH, USA.,Department of Molecular Medicine, University of South Florida, College of Medicine, Tampa, FL, USA
| | - Kyle C McGill Percy
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH, USA
| | - Xinming Wang
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH, USA
| | - Tian Liu
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH, USA
| | - Stephen B Liggett
- Department of Molecular Pharmacology and Physiology, University of South Florida, College of Medicine, Tampa, FL, USA
| | - David E Kang
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH, USA.,Louis Stokes Cleveland VA Medical Center, Cleveland, OH, USA
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11
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Cuestas Torres DM, Cardenas FP. Synaptic plasticity in Alzheimer's disease and healthy aging. Rev Neurosci 2021; 31:245-268. [PMID: 32250284 DOI: 10.1515/revneuro-2019-0058] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 11/01/2019] [Indexed: 12/17/2022]
Abstract
The strength and efficiency of synaptic connections are affected by the environment or the experience of the individual. This property, called synaptic plasticity, is directly related to memory and learning processes and has been modeled at the cellular level. These types of cellular memory and learning models include specific stimulation protocols that generate a long-term strengthening of the synapses, called long-term potentiation, or a weakening of the said long-term synapses, called long-term depression. Although, for decades, researchers have believed that the main cause of the cognitive deficit that characterizes Alzheimer's disease (AD) and aging was the loss of neurons, the hypothesis of an imbalance in the cellular and molecular mechanisms of synaptic plasticity underlying this deficit is currently widely accepted. An understanding of the molecular and cellular changes underlying the process of synaptic plasticity during the development of AD and aging will direct future studies to specific targets, resulting in the development of much more efficient and specific therapeutic strategies. In this review, we classify, discuss, and describe the main findings related to changes in the neurophysiological mechanisms of synaptic plasticity in excitatory synapses underlying AD and aging. In addition, we suggest possible mechanisms in which aging can become a high-risk factor for the development of AD and how its development could be prevented or slowed.
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Affiliation(s)
- Diana Marcela Cuestas Torres
- Departamento de Psicología and Departamento de Biología, Laboratorio de Neurociencia y Comportamiento, Universidad de los Andes, Cra 1 N° 18A-12, CP 111711, Bogotá, Colombia
| | - Fernando P Cardenas
- Departamento de Psicología, Laboratorio de Neurociencia y Comportamiento, Universidad de los Andes, Cra 1 N° 18A-12, CP 111711, Bogotá, Colombia
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12
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Olajide OJ, Chapman CA. Amyloid-β (1-42) peptide induces rapid NMDA receptor-dependent alterations at glutamatergic synapses in the entorhinal cortex. Neurobiol Aging 2021; 105:296-309. [PMID: 34144329 DOI: 10.1016/j.neurobiolaging.2021.05.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 04/26/2021] [Accepted: 05/11/2021] [Indexed: 12/29/2022]
Abstract
The hippocampus and entorhinal cortex (EC) accumulate amyloid beta peptides (Aβ) that promote neuropathology in Alzheimer's disease, but the early effects of Aβ on excitatory synaptic transmission in the EC have not been well characterized. To assess the acute effects of Aβ1-42 on glutamatergic synapses, acute brain slices from wildtype rats were exposed to Aβ1-42 or control solution for 3 hours, and tissue was analyzed using protein immunoblotting and quantitative PCR. Presynaptically, Aβ1-42 induced marked reductions in synaptophysin, synapsin-2a mRNA, and mGluR3 mRNA, and increased both VGluT2 protein and Ca2+-activated channel KCa2.2 mRNA levels. Postsynaptically, Aβ1-42 reduced PSD95 and GluN2B protein, and also downregulated GluN2B and GluN2A mRNA, without affecting scaffolding elements SAP97 and PICK1. mGluR5 mRNA was strongly increased, while mGluR1 mRNA was unaffected. Blocking either GluN2A- or GluN2B-containing NMDA receptors did not significantly prevent synaptic changes induced by Aβ1-42, but combined blockade did prevent synaptic alterations. These findings demonstrate that Aβ1-42 rapidly disrupts glutamatergic transmission in the EC through mechanisms involving concurrent activation of GluN2A- and GluN2B-containing NMDA receptors.
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Affiliation(s)
- Olayemi Joseph Olajide
- Division of Neurobiology, Department of Anatomy, University of Ilorin, Ilorin, Nigeria; Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, Québec, Canada
| | - Clifton Andrew Chapman
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, Québec, Canada.
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13
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Stolero N, Frenkel D. The dialog between neurons and microglia in Alzheimer's disease: The neurotransmitters view. J Neurochem 2020; 158:1412-1424. [PMID: 33314073 DOI: 10.1111/jnc.15262] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 11/12/2020] [Accepted: 12/04/2020] [Indexed: 02/06/2023]
Abstract
Microglia play a vital role in maintaining brain homeostasis. Their continuous sensing of surrounding micro-environments is crucial for their activity. Cross talk between specific neurons and microglia might occur through specific neurotransmitter receptors on microglia. Impairment with this interaction might result in pathological activity of microglia against potential insults. The reason for this activity in many neurodegenerative diseases such as Alzheimer's disease (AD) is not known. However, several papers report of the effects of different neurotransmitter agonists on microglial cells function that relate to their activity in AD. This review aims to summarize those works and to raise potential fundamental questions for future research.
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Affiliation(s)
- Nofar Stolero
- Department of Neurobiology, School of Neurobiology, Biochemistry and Biophysics School, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Dan Frenkel
- Department of Neurobiology, School of Neurobiology, Biochemistry and Biophysics School, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.,Sagol School of Neuroscience, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
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14
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Yuan G, Qu X, Zheng B, Neelamegam R, Afshar S, Iyengar S, Pan C, Wang J, Kang HJ, Ondrechen MJ, Poutiainen P, El Fakhri G, Zhang Z, Brownell AL. Design, Synthesis, and Characterization of Benzimidazole Derivatives as Positron Emission Tomography Imaging Ligands for Metabotropic Glutamate Receptor 2. J Med Chem 2020; 63:12060-12072. [PMID: 32981322 DOI: 10.1021/acs.jmedchem.0c01394] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Three benzimidazole derivatives (13-15) have been synthetized as potential positron emission tomography (PET) imaging ligands for mGluR2 in the brain. Of these compounds, 13 exhibits potent binding affinity (IC50 = 7.6 ± 0.9 nM), positive allosteric modulator (PAM) activity (EC50 = 51.2 nM), and excellent selectivity against other mGluR subtypes (>100-fold). [11C]13 was synthesized via O-[11C]methylation of its phenol precursor 25 with [11C]methyl iodide. The achieved radiochemical yield was 20 ± 2% (n = 10, decay-corrected) based on [11C]CO2 with a radiochemical purity of >98% and molar activity of 98 ± 30 GBq/μmol EOS. Ex vivo biodistribution studies revealed reversible accumulation of [11C]13 and hepatobiliary and urinary excretions. PET imaging studies in rats demonstrated that [11C]13 accumulated in the mGluR2-rich brain regions. Pre-administration of mGluR2-selective PAM, 17 reduced the brain uptake of [11C]13, indicating a selective binding. Therefore, [11C]13 is a potential PET imaging ligand for mGluR2 in different central nervous system-related conditions.
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Affiliation(s)
- Gengyang Yuan
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Xiying Qu
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Baohui Zheng
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Ramesh Neelamegam
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Sepideh Afshar
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Suhasini Iyengar
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Chuzhi Pan
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Junfeng Wang
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Hye Jin Kang
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, North Carolina 27514, United States
| | - Mary Jo Ondrechen
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Pekka Poutiainen
- Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital, Kuopio 70210, Finland
| | - Georges El Fakhri
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Zhaoda Zhang
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129, United States
| | - Anna-Liisa Brownell
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
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15
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Hascup KN, Britz J, Findley CA, Tischkau S, Hascup ER. LY379268 Does Not Have Long-Term Procognitive Effects nor Attenuate Glutamatergic Signaling in AβPP/PS1 Mice. J Alzheimers Dis 2020; 68:1193-1209. [PMID: 30909243 DOI: 10.3233/jad-181231] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Chronically elevated basal glutamate levels are hypothesized to attenuate detection of physiological signals thereby inhibiting memory formation and retrieval, while inducing excitotoxicity-mediated neurodegeneration observed in Alzheimer's disease (AD). However, current medication targeting the glutamatergic system, such as memantine, shows limited efficacy and is unable to decelerate disease progression, possibly because it modulates postsynaptic N-methyl-D-aspartate receptors rather than glutamate release or clearance. To determine if decreasing presynaptic glutamate release leads to long-term procognitive effects, we treated AβPP/PS1 mice with LY379268 (3.0 mg/kg; i.p.), a metabotropic glutamate receptor (mGluR)2/3 agonist from 2-6 months of age when elevated glutamate levels are first observed but cognition is unaffected. C57BL/6J genetic background control mice and another cohort of AβPP/PS1 mice received normal saline (i.p.) as vehicle controls. After 6 months off treatment, mice receiving LY379268 did not show long-term improvement as assessed by the Morris water maze (MWM) spatial learning and memory paradigm. Following MWM, mice were isoflurane anesthetized and a glutamate selective microelectrode was used to measure in vivo basal and stimulus-evoked glutamate release and clearance independently from the dentate, CA3, and CA1 hippocampal subregions. Immunohistochemistry was used to measure hippocampal astrogliosis and plaque pathology. Similar to previous studies, we observed elevated basal glutamate, stimulus evoked glutamate release, and astrogliosis in AβPP/PS1 vehicle mice versus C57BL/6J mice. Treatment with LY379268 did not attenuate these responses nor diminish plaque pathology. The current study builds upon previous research demonstrating hyperglutamatergic hippocampal signaling in AβPP/PS1 mice; however, long-term therapeutic efficacy of LY379268 in AβPP/PS1 was not observed.
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Affiliation(s)
- Kevin N Hascup
- Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neurosciences Institute, Springfield, IL, USA.,Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Jesse Britz
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Caleigh A Findley
- Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neurosciences Institute, Springfield, IL, USA.,Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Shelley Tischkau
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Erin R Hascup
- Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neurosciences Institute, Springfield, IL, USA.,Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
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16
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Michalska P, León R. When It Comes to an End: Oxidative Stress Crosstalk with Protein Aggregation and Neuroinflammation Induce Neurodegeneration. Antioxidants (Basel) 2020; 9:antiox9080740. [PMID: 32806679 PMCID: PMC7463521 DOI: 10.3390/antiox9080740] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/27/2020] [Accepted: 08/07/2020] [Indexed: 12/13/2022] Open
Abstract
Neurodegenerative diseases are characterized by a progressive loss of neurons in the brain or spinal cord that leads to a loss of function of the affected areas. The lack of effective treatments and the ever-increasing life expectancy is raising the number of individuals affected, having a tremendous social and economic impact. The brain is particularly vulnerable to oxidative damage given the high energy demand, low levels of antioxidant defenses, and high levels of metal ions. Driven by age-related changes, neurodegeneration is characterized by increased oxidative stress leading to irreversible neuronal damage, followed by cell death. Nevertheless, neurodegenerative diseases are known as complex pathologies where several mechanisms drive neuronal death. Herein we discuss the interplay among oxidative stress, proteinopathy, and neuroinflammation at the early stages of neurodegenerative diseases. Finally, we discuss the use of the Nrf2-ARE pathway as a potential therapeutic strategy based on these molecular mechanisms to develop transformative medicines.
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Affiliation(s)
- Patrycja Michalska
- Instituto Teófilo Hernando y Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, 28029 Madrid, Spain
- Instituto de Investigación Sanitaria, Servicio de Farmacología Clínica, Hospital Universitario de la Princesa, 28006 Madrid, Spain
- Correspondence: (P.M.); (R.L.); Tel.: +34-91-497-27-66 (P.M. & R.L.)
| | - Rafael León
- Instituto Teófilo Hernando y Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, 28029 Madrid, Spain
- Instituto de Investigación Sanitaria, Servicio de Farmacología Clínica, Hospital Universitario de la Princesa, 28006 Madrid, Spain
- Instituto de Química Médica, Consejo Superior de Investigaciones Científicas (IQM-CSIC), 28006 Madrid, Spain
- Correspondence: (P.M.); (R.L.); Tel.: +34-91-497-27-66 (P.M. & R.L.)
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17
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Findley CA, Bartke A, Hascup KN, Hascup ER. Amyloid Beta-Related Alterations to Glutamate Signaling Dynamics During Alzheimer's Disease Progression. ASN Neuro 2020; 11:1759091419855541. [PMID: 31213067 PMCID: PMC6582288 DOI: 10.1177/1759091419855541] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Alzheimer’s disease (AD) ranks sixth on the Centers for Disease Control and Prevention Top 10 Leading Causes of Death list for 2016, and the Alzheimer’s Association attributes 60% to 80% of dementia cases as AD related. AD pathology hallmarks include accumulation of senile plaques and neurofibrillary tangles; however, evidence supports that soluble amyloid beta (Aβ), rather than insoluble plaques, may instigate synaptic failure. Soluble Aβ accumulation results in depression of long-term potentiation leading to cognitive deficits commonly characterized in AD. The mechanisms through which Aβ incites cognitive decline have been extensively explored, with a growing body of evidence pointing to modulation of the glutamatergic system. The period of glutamatergic hypoactivation observed alongside long-term potentiation depression and cognitive deficits in later disease stages may be the consequence of a preceding period of increased glutamatergic activity. This review will explore the Aβ-related changes to the tripartite glutamate synapse resulting in altered cell signaling throughout disease progression, ultimately culminating in oxidative stress, synaptic dysfunction, and neuronal loss.
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Affiliation(s)
- Caleigh A Findley
- 1 Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neuroscience Institute, Southern Illinois University School of Medicine, Springfield, IL, USA.,2 Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Andrzej Bartke
- 3 Department of Internal Medicine, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Kevin N Hascup
- 1 Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neuroscience Institute, Southern Illinois University School of Medicine, Springfield, IL, USA.,2 Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA.,4 Department of Molecular Biology, Microbiology & Biochemistry, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Erin R Hascup
- 1 Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neuroscience Institute, Southern Illinois University School of Medicine, Springfield, IL, USA.,2 Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
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18
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Cai X, Zhang K, Xie X, Zhu X, Feng J, Jin Z, Zhang H, Tian M, Chen H. Self-assembly hollow manganese Prussian white nanocapsules attenuate Tau-related neuropathology and cognitive decline. Biomaterials 2019; 231:119678. [PMID: 31864019 DOI: 10.1016/j.biomaterials.2019.119678] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 12/06/2019] [Accepted: 12/08/2019] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD) is a prevalent chronic neurodegenerative disease. However, to date, none of the developed drug candidates targeting at a single therapeutic target of AD have achieved success in clinical trials. Herein, we proposed a hypothesis of hollow manganese Prussian white nanocapsules (HMPWCs)-mediated attenuation of Tau-related pathology and alleviation of cognitive decline via simultaneously alleviating neuroinflammation, scavenging reactive oxygen species, and reducing hyperphosphorylated Tau proteins. The HMPWCs self-assemblied with manganese Prussian white analogue and bovine serum albumin via a novel biomimetic mineralization present good biocompatibility, variable valence states, and low oxidation-reduction potential. They own the outstanding capabilities of relieving oxidative stress, inhibiting Tau neuropathology, and counteracting neuroinflammation, which could be used to treat Tau-related AD-like neurodegeneration. Importantly, they can also attenuate the cognitive impairments of Tau-related AD-like rats without significant side effects. This research takes the advantages of catalytic chemistry, nanomedicine and specific neurodegenerative microenvironment together, providing an alternative efficient treatment strategy for Tau-related neurodegeneration diseases, such as AD, Pick's disease, frontotemporal dementia, Creutzfeldt-Jakob Disease and progressive supranuclear palsy.
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Affiliation(s)
- Xiaojun Cai
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, PR China; Shanghai Institute of Ultrasound in Medicine, The Sixth People's Hospital Affiliated to Shanghai Jiao Tong University, 200050, Shanghai, PR China
| | - Kai Zhang
- Department of Nuclear Medicine and PET-CT Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310009, PR China
| | - Xue Xie
- Shanghai Institute of Ultrasound in Medicine, The Sixth People's Hospital Affiliated to Shanghai Jiao Tong University, 200050, Shanghai, PR China
| | - Xiandi Zhu
- Department of Nuclear Medicine and PET-CT Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310009, PR China
| | - Jin Feng
- Department of Nuclear Medicine and PET-CT Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310009, PR China
| | - Zhiming Jin
- Jiangsu Huayi Technology Limited Company, Changshu, Jiangsu, 215522, PR China
| | - Hong Zhang
- Department of Nuclear Medicine and PET-CT Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310009, PR China; Shanxi Medical University, Taiyuan, Shanxi, PR China; Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang University, Hangzhou, China; The College of Biomedical Engineering and Instrument Science of Zhejiang University, Hangzhou, China
| | - Mei Tian
- Department of Nuclear Medicine and PET-CT Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310009, PR China.
| | - Hangrong Chen
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, PR China.
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19
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Duggal P, Mehan S. Neuroprotective Approach of Anti-Cancer Microtubule Stabilizers Against Tauopathy Associated Dementia: Current Status of Clinical and Preclinical Findings. J Alzheimers Dis Rep 2019; 3:179-218. [PMID: 31435618 PMCID: PMC6700530 DOI: 10.3233/adr-190125] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Neuronal microtubule (MT) tau protein provides cytoskeleton to neuronal cells and plays a vital role including maintenance of cell shape, intracellular transport, and cell division. Tau hyperphosphorylation mediates MT destabilization resulting in axonopathy and neurotransmitter deficit, and ultimately causing Alzheimer’s disease (AD), a dementing disorder affecting vast geriatric populations worldwide, characterized by the existence of extracellular amyloid plaques and intracellular neurofibrillary tangles in a hyperphosphorylated state. Pre-clinically, streptozotocin stereotaxically mimics the behavioral and biochemical alterations similar to AD associated with tau pathology resulting in MT assembly defects, which proceed neuropathological cascades. Accessible interventions like cholinesterase inhibitors and NMDA antagonist clinically provides only symptomatic relief. Involvement of microtubule stabilizers (MTS) prevents tauopathy particularly by targeting MT oriented cytoskeleton and promotes polymerization of tubulin protein. Multiple in vitro and in vivo research studies have shown that MTS can hold substantial potential for the treatment of AD-related tauopathy dementias through restoration of tau function and axonal transport. Moreover, anti-cancer taxane derivatives and epothiolones may have potential to ameliorate MT destabilization and prevent the neuronal structural and functional alterations associated with tauopathies. Therefore, this current review strictly focuses on exploration of various clinical and pre-clinical features available for AD to understand the neuropathological mechanisms as well as introduce pharmacological interventions associated with MT stabilization. MTS from diverse natural sources continue to be of value in the treatment of cancer, suggesting that these agents have potential to be of interest in the treatment of AD-related tauopathy dementia in the future.
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Affiliation(s)
- Pallavi Duggal
- Neuropharmacology Division, ISF College of Pharmacy, Moga, Punjab, India
| | - Sidharth Mehan
- Neuropharmacology Division, ISF College of Pharmacy, Moga, Punjab, India
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20
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Abstract
Abnormalities of glutamatergic transmission are implicated in neuropsychiatric disorders. Among the glutamate receptors, metabotropic (mGlu) 2/3 receptors have recently gained much attention as molecular targets for the treatment of several neuropsychiatric disorders including depression and anxiety. Both orthosteric and allosteric antagonists of mGlu2/3 receptors have been synthesized, and their therapeutic potential has been examined. These research activities have demonstrated the promise of mGlu2/3 receptor antagonists as potential treatment agents for the above-mentioned neuropsychiatric disorders. In particular, it has been considered that the antidepressant effects of mGlu2/3 receptor antagonists are worthy of pursuing, since the antidepressant profiles as well as synaptic/neural mechanisms involved in the actions of mGlu2/3 receptor antagonists are similar to those of ketamine, which has been demonstrated to show potent, rapid and sustained efficacy in patients with depression, even those resistant to the conventionally prescribed antidepressants. In this chapter, the general pharmacology of mGlu2/3 receptor antagonists and their therapeutic potential are reviewed. In particular, I focus on the usefulness of mGlu2/3 receptor antagonists as novel antidepressants, in comparison with ketamine.
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21
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Fu H, Hardy J, Duff KE. Selective vulnerability in neurodegenerative diseases. Nat Neurosci 2018; 21:1350-1358. [PMID: 30250262 DOI: 10.1038/s41593-018-0221-2] [Citation(s) in RCA: 305] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 06/13/2018] [Indexed: 12/12/2022]
Abstract
Neurodegenerative diseases have two general characteristics that are so fundamental we usually take them for granted. The first is that the pathology associated with the disease only affects particular neurons ('selective neuronal vulnerability'); the second is that the pathology worsens with time and impacts more regions in a stereotypical and predictable fashion. The mechanisms underpinning selective neuronal and regional vulnerability have been difficult to dissect, but the recent application of whole-genome technologies, the development of mouse models that reproduce spatial and temporal features of the pathology, and the identification of intrinsic morphological, electrophysiological, and biochemical properties of vulnerable neurons are beginning to shed some light on these fundamental features of neurodegenerative diseases. Here we detail our emerging understanding of the underlying biology of selective neuronal vulnerability and outline some of the areas in which our understanding is incomplete.
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Affiliation(s)
- Hongjun Fu
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain; and Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA.,Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - John Hardy
- Department of Molecular Neuroscience and Reta Lilla Weston Laboratories, Institute of Neurology, London, UK
| | - Karen E Duff
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain; and Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA. .,Department of Psychiatry, Division of Integrative Neuroscience, New York State Psychiatric Institute, New York, NY, USA.
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22
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Neuroimmune Tau Mechanisms: Their Role in the Progression of Neuronal Degeneration. Int J Mol Sci 2018; 19:ijms19040956. [PMID: 29570615 PMCID: PMC5979395 DOI: 10.3390/ijms19040956] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 03/05/2018] [Accepted: 03/08/2018] [Indexed: 12/15/2022] Open
Abstract
Progressive neurodegenerative pathologies in aged populations are an issue of major concern worldwide. The microtubule-associated protein tau is able to self-aggregate to form abnormal supramolecular structures that include small oligomers up to complex polymers. Tauopathies correspond to a group of diseases that share tau pathology as a common etiological agent. Since microglial cells play a preponderant role in innate immunity and are the main source of proinflammatory factors in the central nervous system (CNS), the alterations in the cross-talks between microglia and neuronal cells are the main focus of studies concerning the origins of tauopathies. According to evidence from a series of studies, these changes generate a feedback mechanism reactivating microglia and provoking constant cellular damage. Thus, the previously summarized mechanisms could explain the onset and progression of different tauopathies and their functional/behavioral effects, opening the window towards an understanding of the molecular basis of anomalous tau interactions. Despite clinical and pathological differences, increasing experimental evidence indicates an overlap between tauopathies and synucleinopathies, considering that neuroinflammatory events are involved and the existence of protein misfolding. Neurofibrillary tangles of pathological tau (NFT) and Lewy bodies appear to coexist in certain brain areas. Thus, the co-occurrence of synucleinopathies with tauopathies is evidenced by several investigations, in which NFT were found in the substantia nigra of patients with Parkinson’s disease, suggesting that the pathologies share some common features at the level of neuroinflammatory events.
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Metabotropic glutamate receptors and neurodegenerative diseases. Pharmacol Res 2017; 115:179-191. [DOI: 10.1016/j.phrs.2016.11.013] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 11/11/2016] [Accepted: 11/15/2016] [Indexed: 12/21/2022]
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Bruno V, Caraci F, Copani A, Matrisciano F, Nicoletti F, Battaglia G. The impact of metabotropic glutamate receptors into active neurodegenerative processes: A "dark side" in the development of new symptomatic treatments for neurologic and psychiatric disorders. Neuropharmacology 2016; 115:180-192. [PMID: 27140693 DOI: 10.1016/j.neuropharm.2016.04.044] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 04/22/2016] [Accepted: 04/28/2016] [Indexed: 12/17/2022]
Abstract
Metabotropic glutamate (mGlu) receptor ligands are under clinical development for the treatment of CNS disorders with high social and economic burden, such as schizophrenia, major depressive disorder (MDD), and Parkinson's disease (PD), and are promising drug candidates for the treatment of Alzheimer's disease (AD). So far, clinical studies have shown symptomatic effects of mGlu receptor ligands, but it is unknown whether these drugs act as disease modifiers or, at the opposite end, they accelerate disease progression by enhancing neurodegeneration. This is a fundamental issue in the treatment of PD and AD, and is also an emerging theme in the treatment of schizophrenia and MDD, in which neurodegeneration is also present and contribute to disease progression. Moving from in vitro data and preclinical studies, we discuss the potential impact of drugs targeting mGlu2, mGlu3, mGlu4 and mGlu5 receptor ligands on active neurodegeneration associated with AD, PD, schizophrenia, and MDD. We wish to highlight that our final comments on the best drug candidates are not influenced by commercial interests or by previous or ongoing collaborations with drug companies. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'.
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Affiliation(s)
- Valeria Bruno
- Department of Physiology and Pharmacology, University Sapienza, 00185 Rome, Italy; I.R.C.C.S. Neuromed, 86077 Pozzilli, Italy.
| | - Filippo Caraci
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; I.R.C.C.S. Associazione Oasi Maria S.S., Institute for Research on Mental Retardation and Brain Aging, 94018 Troina, Italy
| | - Agata Copani
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; National Research Council, Institute of Biostructure and Bioimaging (IBB-CNR), 95126 Catania, Italy
| | - Francesco Matrisciano
- Department of Psychiatry and Behavioral Sciences, Northwestern Feinberg School of Medicine, Chicago, USA
| | - Ferdinando Nicoletti
- Department of Physiology and Pharmacology, University Sapienza, 00185 Rome, Italy; I.R.C.C.S. Neuromed, 86077 Pozzilli, Italy
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25
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Chumakov I, Nabirotchkin S, Cholet N, Milet A, Boucard A, Toulorge D, Pereira Y, Graudens E, Traoré S, Foucquier J, Guedj M, Vial E, Callizot N, Steinschneider R, Maurice T, Bertrand V, Scart-Grès C, Hajj R, Cohen D. Combining two repurposed drugs as a promising approach for Alzheimer's disease therapy. Sci Rep 2015; 5:7608. [PMID: 25566747 PMCID: PMC5378993 DOI: 10.1038/srep07608] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 11/19/2014] [Indexed: 02/08/2023] Open
Abstract
Alzheimer disease (AD) represents a major medical problem where mono-therapeutic interventions demonstrated only a limited efficacy so far. We explored the possibility of developing a combinational therapy that might prevent the degradation of neuronal and endothelial structures in this disease. We argued that the distorted balance between excitatory (glutamate) and inhibitory (GABA/glycine) systems constitutes a therapeutic target for such intervention. We found that a combination of two approved drugs – acamprosate and baclofen – synergistically protected neurons and endothelial structures in vitro against amyloid-beta (Aβ) oligomers. The neuroprotective effects of these drugs were mediated by modulation of targets in GABA/glycinergic and glutamatergic pathways. In vivo, the combination alleviated cognitive deficits in the acute Aβ25–35 peptide injection model and in the mouse mutant APP transgenic model. Several patterns altered in AD were also synergistically normalised. Our results open up the possibility for a promising therapeutic approach for AD by combining repurposed drugs.
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Affiliation(s)
- Ilya Chumakov
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | | | - Nathalie Cholet
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | - Aude Milet
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | - Aurélie Boucard
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | - Damien Toulorge
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | - Yannick Pereira
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | - Esther Graudens
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | - Sory Traoré
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | - Julie Foucquier
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | - Mickael Guedj
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | - Emmanuel Vial
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | | | | | - Tangui Maurice
- 1] Université de Montpellier 2, 34095 Montpellier, France; Inserm, U710, 34095 Montpellier, France; EPHE, 75017 Paris, France [2] Amylgen, 2196 bd de la Lironde, 34980 Montferrier-sur-Lez, France
| | - Viviane Bertrand
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | | | - Rodolphe Hajj
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
| | - Daniel Cohen
- Pharnext, 11 rue des Peupliers, 92130 Issy-Les-Moulineaux, France
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26
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Proneurogenic Group II mGluR antagonist improves learning and reduces anxiety in Alzheimer Aβ oligomer mouse. Mol Psychiatry 2014; 19:1235-42. [PMID: 25113378 PMCID: PMC4217144 DOI: 10.1038/mp.2014.87] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 06/02/2014] [Accepted: 06/06/2014] [Indexed: 01/30/2023]
Abstract
Proneurogenic compounds have recently shown promise in some mouse models of Alzheimer's pathology. Antagonists at Group II metabotropic glutamate receptors (Group II mGluR: mGlu2, mGlu3) are reported to stimulate neurogenesis. Agonists at those receptors trigger γ-secretase-inhibitor-sensitive biogenesis of Aβ42 peptides from isolated synaptic terminals, which is selectively suppressed by antagonist pretreatment. We have assessed the therapeutic potential of chronic pharmacological inhibition of Group II mGluR in Dutch APP (Alzheimer's amyloid precursor protein E693Q) transgenic mice that accumulate Dutch amyloid-β (Aβ) oligomers but never develop Aβ plaques. BCI-838 is a clinically well-tolerated, orally bioavailable, investigational prodrug that delivers to the brain BCI-632, the active Group II mGluR antagonist metabolite. Dutch Aβ-oligomer-forming APP transgenic mice (APP E693Q) were dosed with BCI-838 for 3 months. Chronic treatment with BCI-838 was associated with reversal of transgene-related amnestic behavior, reduction in anxiety, reduction in levels of brain Aβ monomers and oligomers, and stimulation of hippocampal neurogenesis. Group II mGluR inhibition may offer a unique package of relevant properties as an Alzheimer's disease therapeutic or prophylactic by providing both attenuation of neuropathology and stimulation of repair.
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27
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Durand D, Carniglia L, Beauquis J, Caruso C, Saravia F, Lasaga M. Astroglial mGlu3 receptors promote alpha-secretase-mediated amyloid precursor protein cleavage. Neuropharmacology 2014; 79:180-9. [DOI: 10.1016/j.neuropharm.2013.11.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 09/26/2013] [Accepted: 11/20/2013] [Indexed: 12/21/2022]
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Cheng X, Wu J, Geng M, Xiong J. Role of synaptic activity in the regulation of amyloid beta levels in Alzheimer's disease. Neurobiol Aging 2013; 35:1217-32. [PMID: 24368087 DOI: 10.1016/j.neurobiolaging.2013.11.021] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2012] [Revised: 11/03/2013] [Accepted: 11/24/2013] [Indexed: 01/27/2023]
Abstract
Alzheimer's disease (AD) is the most common form of dementia. Accumulation of amyloid-beta (Aβ) peptides is regarded as the critical component associated with AD pathogenesis, which is derived from the amyloid precursor protein (APP) cleavage. Recent studies suggest that synaptic activity is one of the most important factors that regulate Aβ levels. It has been found that synaptic activity facilitates APP internalization and influences APP cleavage. Glutamatergic, cholinergic, serotonergic, leptin, adrenergic, orexin, and gamma-amino butyric acid receptors, as well as the activity-regulated cytoskeleton-associated protein (Arc) are all involved in these processes. The present review summarizes the evidence for synaptic activity-modulated Aβ levels and the mechanisms underlying this regulation. Interestingly, the immediate early gene product Arc may also be the downstream signaling molecule of several receptors in the synaptic activity-modulated Aβ levels. Elucidating how Aβ levels are regulated by synaptic activity may provide new insights in both the understanding of the pathogenesis of AD and in the development of therapies to slow down the progression of AD.
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Affiliation(s)
- Xiaofang Cheng
- Department of Physiology, Third Military Medical University, Chongqing, China
| | - Jian Wu
- Department of Physiology, Third Military Medical University, Chongqing, China
| | - Miao Geng
- Institute of Geriatrics, General Hospital of Chinese PLA, Beijing, China
| | - Jiaxiang Xiong
- Department of Physiology, Third Military Medical University, Chongqing, China.
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29
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Revett TJ, Baker GB, Jhamandas J, Kar S. Glutamate system, amyloid ß peptides and tau protein: functional interrelationships and relevance to Alzheimer disease pathology. J Psychiatry Neurosci 2013; 38:6-23. [PMID: 22894822 PMCID: PMC3529221 DOI: 10.1503/jpn.110190] [Citation(s) in RCA: 202] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Alzheimer disease is the most prevalent form of dementia globally and is characterized premortem by a gradual memory loss and deterioration of higher cognitive functions and postmortem by neuritic plaques containing amyloid ß peptide and neurofibrillary tangles containing phospho-tau protein. Glutamate is the most abundant neurotransmitter in the brain and is essential to memory formation through processes such as long-term potentiation and so might be pivotal to Alzheimer disease progression. This review discusses how the glutamatergic system is impaired in Alzheimer disease and how interactions of amyloid ß and glutamate influence synaptic function, tau phosphorylation and neurodegeneration. Interestingly, glutamate not only influences amyloid ß production, but also amyloid ß can alter the levels of glutamate at the synapse, indicating that small changes in the concentrations of both molecules could influence Alzheimer disease progression. Finally, we describe how the glutamate receptor antagonist, memantine, has been used in the treatment of individuals with Alzheimer disease and discuss its effectiveness.
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Affiliation(s)
| | | | | | - Satyabrata Kar
- Correspondence to: S. Kar, Centre for Prions and Protein Folding Diseases, Departments of Medicine (Neurology) and Psychiatry, University of Alberta, Edmonton AB T6G 2M8;
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30
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Piers TM, Kim DH, Kim BC, Regan P, Whitcomb DJ, Cho K. Translational Concepts of mGluR5 in Synaptic Diseases of the Brain. Front Pharmacol 2012. [PMID: 23205012 PMCID: PMC3506921 DOI: 10.3389/fphar.2012.00199] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The G-protein coupled receptor family of glutamate receptors, termed metabotropic glutamate receptors (mGluRs), are implicated in numerous cellular mechanisms ranging from neural development to the processing of cognitive, sensory, and motor information. Over the last decade, multiple mGluR-related signal cascades have been identified at excitatory synapses, indicating their potential roles in various forms of synaptic function and dysfunction. This review highlights recent studies investigating mGluR5, a subtype of group I mGluRs, and its association with a number of developmental, psychiatric, and senile synaptic disorders with respect to associated synaptic proteins, with an emphasis on translational pre-clinical studies targeting mGluR5 in a range of synaptic diseases of the brain.
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Affiliation(s)
- Thomas M Piers
- School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol Bristol, UK
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31
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Hovelsø N, Sotty F, Montezinho LP, Pinheiro PS, Herrik KF, Mørk A. Therapeutic potential of metabotropic glutamate receptor modulators. Curr Neuropharmacol 2012; 10:12-48. [PMID: 22942876 PMCID: PMC3286844 DOI: 10.2174/157015912799362805] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2010] [Revised: 01/10/2011] [Accepted: 03/04/2011] [Indexed: 12/21/2022] Open
Abstract
Glutamate is the main excitatory neurotransmitter in the central nervous system (CNS) and is a major player in complex brain functions. Glutamatergic transmission is primarily mediated by ionotropic glutamate receptors, which include NMDA, AMPA and kainate receptors. However, glutamate exerts modulatory actions through a family of metabotropic G-protein-coupled glutamate receptors (mGluRs). Dysfunctions of glutamatergic neurotransmission have been implicated in the etiology of several diseases. Therefore, pharmacological modulation of ionotropic glutamate receptors has been widely investigated as a potential therapeutic strategy for the treatment of several disorders associated with glutamatergic dysfunction. However, blockade of ionotropic glutamate receptors might be accompanied by severe side effects due to their vital role in many important physiological functions. A different strategy aimed at pharmacologically interfering with mGluR function has recently gained interest. Many subtype selective agonists and antagonists have been identified and widely used in preclinical studies as an attempt to elucidate the role of specific mGluRs subtypes in glutamatergic transmission. These studies have allowed linkage between specific subtypes and various physiological functions and more importantly to pathological states. This article reviews the currently available knowledge regarding the therapeutic potential of targeting mGluRs in the treatment of several CNS disorders, including schizophrenia, addiction, major depressive disorder and anxiety, Fragile X Syndrome, Parkinson’s disease, Alzheimer’s disease and pain.
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Affiliation(s)
- N Hovelsø
- Department of Neurophysiology, H. Lundbeck A/S, Ottiliavej 9, 2500 Copenhagen-Valby, Denmark
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32
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Diversity of metabotropic glutamate receptor-interacting proteins and pathophysiological functions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 970:63-79. [PMID: 22351051 DOI: 10.1007/978-3-7091-0932-8_3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In the mammalian brain, the large majority of excitatory synapses express pre- and postsynaptic glutamate receptors. These are ion channels and G protein-coupled membrane proteins that are organized into functional signaling complexes. Here, we will review the nature and pathophysiological functions of the scaffolding proteins associated to these receptors, focusing on the G protein-coupled subtypes.
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33
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Thathiah A, De Strooper B. The role of G protein-coupled receptors in the pathology of Alzheimer's disease. Nat Rev Neurosci 2011; 12:73-87. [DOI: 10.1038/nrn2977] [Citation(s) in RCA: 212] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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34
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Caraci F, Molinaro G, Battaglia G, Giuffrida ML, Riozzi B, Traficante A, Bruno V, Cannella M, Merlo S, Wang X, Heinz BA, Nisenbaum ES, Britton TC, Drago F, Sortino MA, Copani A, Nicoletti F. Targeting group II metabotropic glutamate (mGlu) receptors for the treatment of psychosis associated with Alzheimer's disease: selective activation of mGlu2 receptors amplifies beta-amyloid toxicity in cultured neurons, whereas dual activation of mGlu2 and mGlu3 receptors is neuroprotective. Mol Pharmacol 2010; 79:618-26. [PMID: 21159998 DOI: 10.1124/mol.110.067488] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Dual orthosteric agonists of metabotropic glutamate 2 (mGlu2) and mGlu3 receptors are being developed as novel antipsychotic agents devoid of the adverse effects of conventional antipsychotics. Therefore, these drugs could be helpful for the treatment of psychotic symptoms associated with Alzheimer's disease (AD). In experimental animals, the antipsychotic activity of mGlu2/3 receptor agonists is largely mediated by the activation of mGlu2 receptors and is mimicked by selective positive allosteric modulators (PAMs) of mGlu2 receptors. We investigated the distinct influence of mGlu2 and mGlu3 receptors in mixed and pure neuronal cultures exposed to synthetic β-amyloid protein (Aβ) to model neurodegeneration occurring in AD. The mGlu2 receptor PAM, N-4'-cyano-biphenyl-3-yl)-N-(3-pyridinylmethyl)-ethanesulfonamide hydrochloride (LY566332), devoid of toxicity per se, amplified Aβ-induced neurodegeneration, and this effect was prevented by the mGlu2/3 receptor antagonist (2S,1'S,2'S)-2-(9-xanthylmethyl)-2-(2'-carboxycyclopropyl)glycine (LY341495). LY566332 potentiated Aβ toxicity regardless of the presence of glial mGlu3 receptors, but it was inactive when neurons lacked mGlu2 receptors. The dual mGlu2/3 receptor agonist, (-)-2-oxa-4-aminobicyclo[3.1.0]exhane-4,6-dicarboxylic acid (LY379268), was neuroprotective in mixed cultures via a paracrine mechanism mediated by transforming growth factor-β1. LY379268 lost its protective activity in neurons grown with astrocytes lacking mGlu3 receptors, indicating that protection against Aβ neurotoxicity was mediated entirely by glial mGlu3 receptors. The selective noncompetitive mGlu3 receptor antagonist, (3S)-1-(5-bromopyrimidin-2-yl)-N-(2,4-dichlorobenzyl)pyrrolidin-3-amine methanesulfonate hydrate (LY2389575), amplified Aβ toxicity on its own, and, interestingly, unmasked a neurotoxic activity of LY379268, which probably was mediated by the activation of mGlu2 receptors. These data indicate that selective potentiation of mGlu2 receptors enhances neuronal vulnerability to Aβ, whereas dual activation of mGlu2 and mGlu3 receptors is protective against Aβ-induced toxicity.
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Affiliation(s)
- Filippo Caraci
- Department of Pharmaceutical Sciences, University of Catania, Catania, Italy
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35
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Price DL, Rockenstein E, Ubhi K, Phung V, MacLean-Lewis N, Askay D, Cartier A, Spencer B, Patrick C, Desplats P, Ellisman MH, Masliah E. Alterations in mGluR5 expression and signaling in Lewy body disease and in transgenic models of alpha-synucleinopathy--implications for excitotoxicity. PLoS One 2010; 5:e14020. [PMID: 21103359 PMCID: PMC2982819 DOI: 10.1371/journal.pone.0014020] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2010] [Accepted: 10/19/2010] [Indexed: 12/21/2022] Open
Abstract
Dementia with Lewy bodies (DLB) and Parkinson's Disease (PD) are neurodegenerative disorders of the aging population characterized by the abnormal accumulation of alpha-synuclein (alpha-syn). Previous studies have suggested that excitotoxicity may contribute to neurodegeneration in these disorders, however the underlying mechanisms and their relationship to alpha-syn remain unclear. For this study we proposed that accumulation of alpha-syn might result in alterations in metabotropic glutamate receptors (mGluR), particularly mGluR5 which has been linked to deficits in murine models of PD. In this context, levels of mGluR5 were analyzed in the brains of PD and DLB human cases and alpha-syn transgenic (tg) mice and compared to age-matched, unimpaired controls, we report a 40% increase in the levels of mGluR5 and beta-arrestin immunoreactivity in the frontal cortex, hippocampus and putamen in DLB cases and in the putamen in PD cases. In the hippocampus, mGluR5 was more abundant in the CA3 region and co-localized with alpha-syn aggregates. Similarly, in the hippocampus and basal ganglia of alpha-syn tg mice, levels of mGluR5 were increased and mGluR5 and alpha-syn were co-localized and co-immunoprecipitated, suggesting that alpha-syn interferes with mGluR5 trafficking. The increased levels of mGluR5 were accompanied by a concomitant increase in the activation of downstream signaling components including ERK, Elk-1 and CREB. Consistent with the increased accumulation of alpha-syn and alterations in mGluR5 in cognitive- and motor-associated brain regions, these mice displayed impaired performance in the water maze and pole test, these behavioral alterations were reversed with the mGluR5 antagonist, MPEP. Taken together the results from study suggest that mGluR5 may directly interact with alpha-syn resulting in its over activation and that this over activation may contribute to excitotoxic cell death in select neuronal regions. These results highlight the therapeutic importance of mGluR5 antagonists in alpha-synucleinopathies.
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Affiliation(s)
- Diana L. Price
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
- National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, California, United States of America
| | - Edward Rockenstein
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
| | - Kiren Ubhi
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
| | - Van Phung
- National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, California, United States of America
- Center for Research in Biological Systems, University of California San Diego, La Jolla, California, United States of America
| | - Natalie MacLean-Lewis
- National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, California, United States of America
- Center for Research in Biological Systems, University of California San Diego, La Jolla, California, United States of America
| | - David Askay
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
- National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, California, United States of America
| | - Anna Cartier
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
| | - Brian Spencer
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
| | - Christina Patrick
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
| | - Paula Desplats
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
| | - Mark H. Ellisman
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
- National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, California, United States of America
- Center for Research in Biological Systems, University of California San Diego, La Jolla, California, United States of America
| | - Eliezer Masliah
- Department of Neurosciences, University of California San Diego, La Jolla, California, United States of America
- Department of Pathology, University of California San Diego, La Jolla, California, United States of America
- * E-mail:
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Altered distribution of mGlu2 receptors in β-amyloid-affected brain regions of Alzheimer cases and aged PS2APP mice. Brain Res 2010; 1363:180-90. [PMID: 20875805 DOI: 10.1016/j.brainres.2010.09.072] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Revised: 09/16/2010] [Accepted: 09/19/2010] [Indexed: 01/28/2023]
Abstract
Altered glutamatergic synaptic transmission is among the key events defining the course of Alzheimer's disease (AD). mGlu2 receptors, a subtype of group II metabotropic glutamate receptors, regulate (as autoreceptors) fast synaptic transmission in the CNS via the controlled release of the excitatory amino acid glutamate. Since their pharmacological manipulation in rodents has been reported to affect cognition, they are potential drug targets for AD therapy. We examined the fate of these receptors in cases of AD as well as in aging PS2APP mice--a proposed model of the disease. In vitro binding of [(3)H]LY354740, a selective group II agonist (with selective affinity for mGlu2 receptors, under the assay conditions used) and quantitative radioautography revealed a partial, but highly significant, loss of receptors in amyloid-affected discrete brain regions of AD cases and PS2APP mice. Among the mouse brain regions affected were, above all, the subiculum but also frontolateral cortex, dentate gyrus, lacunosum moleculare and caudate putamen. In AD, significant receptor losses were registered in entorhinal cortex and lacunosum moleculare (40% and 35%, respectively). These findings have implications for the development of selective ligands for symptomatic therapy in AD and for its diagnosis.
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Group II metabotropic glutamate receptor stimulation triggers production and release of Alzheimer's amyloid(beta)42 from isolated intact nerve terminals. J Neurosci 2010; 30:3870-5. [PMID: 20237257 DOI: 10.1523/jneurosci.4717-09.2010] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Aberrant accumulation of amyloid beta (Abeta) oligomers may underlie the cognitive failure of Alzheimer's disease (AD). All species of Abeta peptides are produced physiologically during normal brain activity. Therefore, elucidation of mechanisms that interconnect excitatory glutamatergic neurotransmission, synaptic amyloid precursor protein (APP) processing and production of its metabolite, Abeta, may reveal synapse-specific strategies for suppressing the pathological accumulation of Abeta oligomers and fibrils that characterize AD. To study synaptic APP processing, we used isolated intact nerve terminals (cortical synaptoneurosomes) from TgCRND8 mice, which express a human APP with familial AD mutations. Potassium chloride depolarization caused sustained release from synaptoneurosomes of Abeta(42) as well as Abeta(40), and appeared to coactivate alpha-, beta- and gamma-secretases, which are known to generate a family of released peptides, including Abeta(40) and Abeta(42). Stimulation of postsynaptic group I metabotropic glutamate receptor (mGluRs) with DHPG (3,5-dihydroxyphenylglycine) induced a rapid accumulation of APP C-terminal fragments (CTFs) in the synaptoneurosomes, a family of membrane-bound intermediates generated from APP metabolized by alpha- and beta-secretases. Following stimulation with the group II mGluR agonist DCG-IV, levels of APP CTFs in the synaptoneurosomes initially increased but then returned to baseline by 10 min after stimulation. This APP CTF degradation phase was accompanied by sustained accumulation of Abeta(42) in the releasate, which was blocked by the group II mGluR antagonist LY341495. These data suggest that group II mGluR may trigger synaptic activation of all three secretases and that suppression of group II mGluR signaling may be a therapeutic strategy for selectively reducing synaptic generation of Abeta(42).
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Francis PT, Ramírez MJ, Lai MK. Neurochemical basis for symptomatic treatment of Alzheimer's disease. Neuropharmacology 2010; 59:221-9. [PMID: 20156462 DOI: 10.1016/j.neuropharm.2010.02.010] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2009] [Revised: 02/01/2010] [Accepted: 02/09/2010] [Indexed: 02/02/2023]
Abstract
Neuron and synapse loss together with neurotransmitter dysfunction have, along with Abeta deposition and neurofibrillary tangles, been recognized as hallmarks of Alzheimer's disease (AD). Furthermore, clinical and preclinical studies point to neuronal loss and associated neurochemical alterations of several transmitter systems as a main factor underlying both cognitive and neuropsychiatric symptoms. Treatment for the cognitive decline in AD, based on early findings of a cholinergic deficit, has been in the clinic for more than a decade but provides only modest benefit in most patients. Therefore there is still considerable scope for new treatments that demonstrate greater efficacy against cognitive dysfunction in spite of the fact that the mainstays of current treatments, the cholinesterase inhibitors Aricept, Exelon and Reminyl (Razadyne) will become generic over the next few years. However, the most important area for drug development is for the treatment of behavioural disturbance in AD since many existing treatments have limited efficacy and have potentially life-threatening side effects. This review examines the neurochemical underpinning of both cognitive and neuropsychiatric symptoms in dementia and provides some basis for rational drug development.
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Affiliation(s)
- Paul T Francis
- Wolfson Centre for Age-Related Diseases, King's College London, London, UK.
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Bonda DJ, Mailankot M, Stone JG, Garrett MR, Staniszewska M, Castellani RJ, Siedlak SL, Zhu X, Lee HG, Perry G, Nagaraj RH, Smith MA. Indoleamine 2,3-dioxygenase and 3-hydroxykynurenine modifications are found in the neuropathology of Alzheimer's disease. Redox Rep 2010; 15:161-8. [PMID: 20663292 PMCID: PMC2956440 DOI: 10.1179/174329210x12650506623645] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Tryptophan metabolism, through the kynurenine pathway, produces neurotoxic intermediates that are implicated in the pathogenesis of Alzheimer's disease. In particular, oxidative stress via 3-hydroxykynurenine (3-HK) and its cleaved product 3-hydroxyanthranilic acid (3-HAA) significantly damages neuronal tissue and may potentially contribute to a cycle of neurodegeneration through consequent amyloid-beta accumulation, glial activation, and up-regulation of the kynurenine pathway. To determine the role of the kynurenine pathway in eliciting and continuing oxidative stress within Alzheimer's diseased brains, we used immunocytochemical methods to show elevated levels of 3-HK modifications and the upstream, rate-limiting enzyme indoleamine 2,3-dioxygenase (IDO-1) in Alzheimer's diseased brains when compared to controls. Importantly, the association of IDO-1 with senile plaques was confirmed and, for the first time, IDO-1 was shown to be specifically localized in conjunction with neurofibrillary tangles. As senile plaques and neurofibrillary tangles are the pathological hallmarks of Alzheimer's disease, our study provides further evidence that the kynurenine pathway is involved with the destructive neurodegenerative pathway of Alzheimer's disease.
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Affiliation(s)
- David J. Bonda
- Department of PathologyCase Western Reserve University, Cleveland, Ohio, USA
| | - Maneesh Mailankot
- Department of Ophthalmology and Visual SciencesCase Western Reserve University, Cleveland, Ohio, USA
| | - Jeremy G. Stone
- Department of PathologyCase Western Reserve University, Cleveland, Ohio, USA
| | - Matthew R. Garrett
- Departments of PathologyCase Western Reserve University, Cleveland, Ohio, USA, Otolaryngology-Head and Neck Surgery, Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Magdalena Staniszewska
- Department of Ophthalmology and Visual SciencesCase Western Reserve University, Cleveland, Ohio, USA, Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts, USA
| | | | - Sandra L. Siedlak
- Department of PathologyCase Western Reserve University, Cleveland, Ohio, USA
| | - Xiongwei Zhu
- Department of PathologyCase Western Reserve University, Cleveland, Ohio, USA
| | - Hyoung-gon Lee
- Department of PathologyCase Western Reserve University, Cleveland, Ohio, USA
| | - George Perry
- Department of PathologyCase Western Reserve University, Cleveland, Ohio, USA, UTSA Neurosciences Institute and Department of Biology, University of Texas at San Antonio, San Antonio, Texas, USA
| | - Ram H. Nagaraj
- Department of Ophthalmology and Visual SciencesCase Western Reserve University, Cleveland, Ohio, USA
| | - Mark A. Smith
- Department of PathologyCase Western Reserve University, 2103 Cornell Road, Cleveland, Ohio 44106, USA;,
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40
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Su B, Liu H, Wang X, Chen SG, Siedlak SL, Kondo E, Choi R, Takeda A, Castellani RJ, Perry G, Smith MA, Zhu X, Lee HG. Ectopic localization of FOXO3a protein in Lewy bodies in Lewy body dementia and Parkinson's disease. Mol Neurodegener 2009; 4:32. [PMID: 19627592 PMCID: PMC2723103 DOI: 10.1186/1750-1326-4-32] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Accepted: 07/23/2009] [Indexed: 12/25/2022] Open
Abstract
Lewy bodies and Lewy neurites constitute the cardinal neuropathological features of both Parkinson's disease (PD) and Lewy body dementia (LBD). Whereas α-synuclein has been found to be the major component of the Lewy body, the mechanisms by which neurons degenerate, as well as basic mechanisms involved in the formation of α-synuclein-related inclusions, remain obscure. We have suggested previously that potential mechanisms are likely to leave a "molecular signature" or protein adduct within the Lewy body, and have found examples of such signatures in previous studies. In this study, we demonstrate increased FOXO3 in association with Lewy bodies and Lewy neurites in LBD and PD brain tissue. Since FOXO proteins are involved in several pathways responsible for the regulation of cell death, cell proliferation, and cell metabolism, the ectopic localization of FOXO3 to Lewy bodies provides evidence that aberrations in basic cellular biochemistry may contribute to inclusion formation, which is likely more complex than a simple "gain of function" toxicity as is commonly opined. In light of the known interaction of FOXO3 and 14-3-3, basic protein-protein interaction between these proteins and α-synuclein may be key.
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Affiliation(s)
- Bo Su
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, USA.
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Casley CS, Lakics V, Lee HG, Broad LM, Day TA, Cluett T, Smith MA, O'Neill MJ, Kingston AE. Up-regulation of astrocyte metabotropic glutamate receptor 5 by amyloid-β peptide. Brain Res 2009; 1260:65-75. [PMID: 19401173 DOI: 10.1016/j.brainres.2008.12.082] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Revised: 12/19/2008] [Accepted: 12/22/2008] [Indexed: 01/20/2023]
Abstract
The effects of amyloid-beta peptide (Aβ) on astrocyte responses to activation of mGlu5 receptors have been investigated using calcium imaging. Pre-incubation with Aβ1-40 peptide for up to 72 h produced a time- and concentration-dependent 2-4 fold enhancement in the magnitude of the intracellular calcium mobilization response to the group I metabotropic glutamate receptor agonist (S)-3,5-dihydroxyphenylglycine (DHPG). In contrast, pre-treatment with Aβ1-40 did not alter the calcium responses induced by other G protein coupled- or ion channel-receptors. Aβ 1-40-enhanced DHPG responses were blocked by the mGlu5 antagonist MPEP but not by inhibitors of voltage dependent calcium channels or by the AMPA/KA receptor antagonist CNQX. Up-regulation of mGlu5 coupled responses was associated with significant increases in astrocyte mGlu5 receptor-mRNA and-protein expression after preincubation with Aβ . The changes observed in vitro were consistent with results obtained from human Alzheimer's disease (AD) patients.Immunostaining for mGlu5 receptors was increased on astrocytes which were colocalized with Aβ plaques in hippocampal tissue from AD patients compared to age-matched controls. These results suggest that modulation of mGlu5 receptors in astrocytes could be an important mechanism in determining the progression of pathology in AD.
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Affiliation(s)
- Christopher S Casley
- Eli Lilly & Company Limited, Lilly Research Centre, Erl Wood Manor, Windlesham, Surrey, UK
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Lee HG, Zhu X, Casadesus G, Pallàs M, Camins A, O'Neill MJ, Nakanishi S, Perry G, Smith MA. The effect of mGluR2 activation on signal transduction pathways and neuronal cell survival. Brain Res 2008; 1249:244-50. [PMID: 19026996 DOI: 10.1016/j.brainres.2008.10.055] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 10/17/2008] [Accepted: 10/18/2008] [Indexed: 12/21/2022]
Abstract
In earlier studies, we found profound alterations in specific signal transduction pathways such as mitogen-activated protein kinase signal pathway that mirrored neuronal cell death in Alzheimer disease (AD). To further delineate the mechanism(s) involved in such aberrant signaling, we subsequently showed that mGluR2 is increased in pyramidal neurons in the hippocampus of AD and often co-localizes with neurofibrillary pathology. Based on these data, we suggested that selective neuronal degeneration in AD may arise through the differential expression and activation of specific receptor populations, such as, mGluR2. In this study, to examine the mechanistic relevance of the above-mentioned in vivo findings, we used cell culture models to show that the activation of mGluR2 leads to the activation of extracellular signal-related kinase (ERK) pathways. Importantly, attesting to the in vivo significance of our findings, this pro-survival signaling pathway is also found to be ectopically activated in AD. We also found that the activation of mGluR2 increases the phosphorylation of tau and that the specific activation of mGluR2 reduces oxidative stress mediated cytotoxicity in neuronal cells. Taken together our findings strongly suggest that mGluR2 may participate in mediating the survival of neurons in the face of selective neuronal dysfunction and degeneration in AD. Additionally, our findings lend support to the notion that tau phosphorylation is a neuroprotective antioxidant response to cellular insults.
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Affiliation(s)
- Hyoung-gon Lee
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, USA.
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Cholinergic and glutamatergic alterations beginning at the early stages of Alzheimer disease: participation of the phospholipase A2 enzyme. Psychopharmacology (Berl) 2008; 198:1-27. [PMID: 18392810 DOI: 10.1007/s00213-008-1092-0] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2007] [Accepted: 01/28/2008] [Indexed: 12/14/2022]
Abstract
RATIONALE Alzheimer disease (AD), a progressive neurodegenerative disorder, is the leading cause of dementia in the elderly. A combination of cholinergic and glutamatergic dysfunction appears to underlie the symptomatology of AD, and thus, treatment strategies should address impairments in both systems. Evidence suggests the involvement of phospholipase A(2) (PLA(2)) enzyme in memory impairment and neurodegeneration in AD via actions on both cholinergic and glutamatergic systems. OBJECTIVES To review cholinergic and glutamatergic alterations underlying cognitive impairment and neuropathology in AD and attempt to link PLA(2) with such alterations. METHODS Medline databases were searched (no date restrictions) for published articles with links among the terms Alzheimer disease (mild, moderate, severe), mild cognitive impairment, choline acetyltransferase, acetylcholinesterase, NGF, NGF receptor, muscarinic receptor, nicotinic receptor, NMDA, AMPA, metabotropic glutamate receptor, atrophy, glucose metabolism, phospholipid metabolism, sphingolipid, membrane fluidity, phospholipase A(2), arachidonic acid, attention, memory, long-term potentiation, beta-amyloid, tau, inflammation, and reactive species. Reference lists of the identified articles were checked to identify additional studies of interest. RESULTS Overall, results suggest the hypothesis that persistent inhibition of cPLA(2) and iPLA(2) isoforms at early stages of AD may play a central role in memory deficits and beta-amyloid production through down-regulation of cholinergic and glutamate receptors. As the disease progresses, beta-amyloid induced up-regulation of cPLA(2) and sPLA(2) isoforms may play critical roles in inflammation and oxidative stress, thus participating in the neurodegenerative process. CONCLUSION Activation and inhibition of specific PLA(2) isoforms at different stages of AD could be of therapeutic importance and delay cognitive dysfunction and neurodegeneration.
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Lee HG, Ueda M, Miyamoto Y, Yoneda Y, Perry G, Smith MA, Zhu X. Aberrant localization of importin alpha1 in hippocampal neurons in Alzheimer disease. Brain Res 2006; 1124:1-4. [PMID: 17070506 DOI: 10.1016/j.brainres.2006.09.084] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Revised: 09/11/2006] [Accepted: 09/24/2006] [Indexed: 11/19/2022]
Abstract
Since many nuclear proteins are ectopically localized in the cytoplasm in the vulnerable neurons in Alzheimer disease (AD), we speculated that there is failure of the cytoplasmic-nuclear transport machinery in AD. In support of this notion, we found that importin alpha1, an essential component of cytoplasmic-nuclear transport, is abnormally accumulated in Hirano bodies in vulnerable hippocampal neurons in AD. These data suggest a hindrance in importin-mediated cytoplasmic-nuclear transport in AD.
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Affiliation(s)
- Hyoung-gon Lee
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, USA.
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45
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Alzheimer' s disease, oxidative stress and gammahydroxybutyrate. Neurobiol Aging 2006; 28:1340-60. [PMID: 16837107 DOI: 10.1016/j.neurobiolaging.2006.06.008] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2006] [Revised: 05/14/2006] [Accepted: 06/12/2006] [Indexed: 12/21/2022]
Abstract
Although the cause of Alzheimer's disease is unknown, oxidative stress, energy depletion, excitotoxicity and vascular endothelial pathology are all considered to play a part in its pathogenesis. In reaction to these adverse events, the Alzheimer brain appears to deploy a highly conserved biological response to tissue stress. Oxidative metabolism is turned down, the expression of antioxidative enzymes is increased and intermediary metabolism is shifted in the direction of the pentose phosphate shunt to promote reductive detoxification, repair and biosynthesis. Gathering evidence suggests that the release of beta-amyloid and the formation of neurofibrillary tangles, the two hallmarks of Alzheimer's disease, are components of this protective response. Gammahydroxybutyrate (GHB), an endogenous short chain fatty acid, may be able to buttress this response. GHB can reduce glucose utilization, shift intermediary metabolism in the direction the pentose phosphate shunt and generate NADPH, a key cofactor in the activity of many antioxidative and reductive enzymes. GHB has been shown to spare cerebral energy utilization, block excitotoxicity and maintain vascular integrity in the face of impaired perfusion. Most important, GHB has repeatedly been shown to prevent the tissue damaging effects of oxidative stress. It may therefore be possible to utilize GHB to strengthen the brain's innate defences against the pathological processes operating in the Alzheimer brain and, in this way, stem the advance of Alzheimer's disease.
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Burbaeva GS, Boksha IS, Tereshkina EB, Savushkina OK, Starodubtseva LI, Turishcheva MS. Glutamate metabolizing enzymes in prefrontal cortex of Alzheimer's disease patients. Neurochem Res 2006; 30:1443-51. [PMID: 16341942 DOI: 10.1007/s11064-005-8654-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/22/2005] [Indexed: 10/25/2022]
Abstract
Amounts of glutamate metabolizing enzymes such as glutamate dehydrogenase (GDH), glutamine synthetase (GS), GS-like protein (GSLP), and phosphate-activated glutaminase (PAG) were compared in prefrontal cortex of control subjects and patients with Alzheimer disease (AD). The target proteins were quantified by ECL-Western immunoblotting in extracts from brain tissue prepared by two different techniques separating enzymes preferentially associated with cytoplasm (GDH I and II isoenzymes, GS, and partially GSLP) and membrane (GDH III, PAG, and partially GSLP) fractions. Amounts of all listed enzymes were found significantly increased in the patient group compared with controls. Some links between the measured values were observed in the control, but not in the AD patient group. The results may suggest for the pathological interruption of regulatory relations between distinct enzymes of glutamate metabolism in brain of AD patients.
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Affiliation(s)
- Gulnur Sh Burbaeva
- Laboratory of Neurochemistry, Mental Health Research Center, Russian Academy of Medical Sciences, Moscow, Russia.
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Zhou J, Neale JH, Pomper MG, Kozikowski AP. NAAG peptidase inhibitors and their potential for diagnosis and therapy. Nat Rev Drug Discov 2005; 4:1015-26. [PMID: 16341066 DOI: 10.1038/nrd1903] [Citation(s) in RCA: 175] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Modulation of N-acetyl-L-aspartyl-L-glutamate peptidase activity with small-molecule inhibitors holds promise for a wide variety of diseases that involve glutamatergic transmission, and has implications for the diagnosis and therapy of cancer. This new class of compounds, of which at least one has entered clinical trials and proven to be well tolerated, has demonstrated efficacy in experimental models of pain, schizophrenia, amyotrophic lateral sclerosis, traumatic brain injury and, when appropriately functionalized, can image prostate cancer. Further investigation of these promising drug candidates will be needed to bring them to the marketplace. The recent publication of the X-ray crystal structure for the enzymatic target of these compounds should facilitate the development of other new agents with enhanced activity that could improve both the diagnosis and treatment of neurological disorders.
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Affiliation(s)
- Jia Zhou
- Acenta Discovery, Inc., 9030 South Rita Road, Suite 300, Tucson, Arizona 85747, USA.
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Schmitt HP. Pouring oil into the fire? On the conundrum of the beneficial effects of NMDA receptor antagonists in Alzheimer disease. Psychopharmacology (Berl) 2005; 179:151-3. [PMID: 15619111 DOI: 10.1007/s00213-004-2110-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Accepted: 11/11/2004] [Indexed: 10/26/2022]
Affiliation(s)
- H Peter Schmitt
- Institute of Pathology, Department for Neuropathology, University of Heidelberg, Im Neuernheimer Feld 220-221, 69120 Heidelberg, Germany.
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Spinelli S, Ballard T, Gatti-McArthur S, Richards GJ, Kapps M, Woltering T, Wichmann J, Stadler H, Feldon J, Pryce CR. Effects of the mGluR2/3 agonist LY354740 on computerized tasks of attention and working memory in marmoset monkeys. Psychopharmacology (Berl) 2005; 179:292-302. [PMID: 15678362 DOI: 10.1007/s00213-004-2126-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2004] [Accepted: 11/19/2004] [Indexed: 11/25/2022]
Abstract
RATIONALE LY354740 is a recently developed metabotropic glutamatergic receptor 2 and 3 (mGluR2/3) agonist. A high density of mGluR2 has been reported in terminal fields of the perforant path in rodents and humans, suggesting its involvement in cognitive functions mediated by the temporal lobe, including memory. A small number of in vivo studies in rodents have assessed the effects of LY354740 on memory tasks, reporting the induction of impaired memory for spatial orientation in a water maze task and for delayed match and non-match to position in an operant version of these tasks. OBJECTIVE In the present primate study, we used radioautography to describe the distribution and intensity of (3)H-LY354740 binding in the hippocampal formation of the common marmoset monkey (Callithrix jacchus) relative to the rat. In the major, in vivo part of the study, the effects of systemic LY354740 on computerized tasks of attention and memory were investigated. METHODS Adult common marmosets were trained to perform a five-choice serial reaction time (5-CSRT) task and a concurrent delayed match-to-position (CDMP) task from the Cambridge Neuropsychological Automated test Battery (CANTAB). Filter tests of LY354740 effects on motor dexterity and motivation for reward revealed high inter-individual variation in sensitivity; therefore, on the 5-CSRT, subjects were tested at a dose range of 3--10 mg/kg, and on the CDMP, subjects were tested at 1--3 or 3--10 mg/kg. RESULTS Radioautography revealed a relatively low level of (3)H-LY354740 binding in the marmoset hippocampal formation compared to the rat. Despite low binding, LY354740 reduced sustained-attention accuracy in the 5-CSRT, and reduced accuracy in two stages of the CDMP. CONCLUSIONS The current study provides novel evidence for the importance of mGluR2/3 in the regulation of primate cognitive functioning.
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Affiliation(s)
- Simona Spinelli
- Behavioural Neurobiology Laboratory, Swiss Federal Institute of Technology Zurich, Schorenstrasse 16, 8603 Schwerzenbach, Switzerland
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Schmitt HP. On the paradox of ion channel blockade and its benefits in the treatment of Alzheimer disease. Med Hypotheses 2005; 65:259-65. [PMID: 15922097 DOI: 10.1016/j.mehy.2005.03.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2005] [Accepted: 03/07/2005] [Indexed: 12/12/2022]
Abstract
The surprisingly beneficial effects in Alzheimer disease (AD) of ion channel blockers (ICB) like memantine that act on NMDA- and other aminergic transmitter receptors are yet poorly understood. NMDA receptor levels and binding were shown to be significantly decreased in AD, in which highly NMDA receptor and Ca(2+) dependent synaptic plasticity and re-modelling are severely compromised. Thus, how could one expect to improve AD by further suppressing NMDA channels with antagonists. Nevertheless, clinical trials with NMDA blockers revealed in moderate to advanced AD surprisingly positive effects. The present paper tries to provides a hypothetical explanation of that paradoxical success of ICBs. Based on evidence from current data, emphasis is put on a profound impairment in the AD brain of the inhibition-excitation balance in the neuronal circuitry to the advantage of excitation. This imbalance is conceived to result from a degeneration of four modulatory aminiergic transmitter systems (serotonin, noradrenalin, acetylcholine, histamine) and related peptidergic systems, the decline of which causes a profound loss of inhibitory impact in the forebrain neuronal circuitry leading to disinhibition of principal neurones ("aminergic disinhibition"). Subsequent Ca(2+) excito-toxicity and its sequelae are suggested to be the basic promotors of the neuro-degeneration and the related mental decline in AD. Re-adjustment of the inhibition-excitation imbalance by decreasing excitation is conceived to be the mechanism that renders ion channel blockade therapeutically successful. Putatively, attempts to increase inhibition, e.g., by application of GABA mimetics that stimulate the production GABA from preserved but "lazy" GABA neurones lacking aminergic facilitation, might be an even better way to achieve the re-balance.
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Affiliation(s)
- H Peter Schmitt
- Institute of Pathology, Department for Neuropathology, University of Heidelberg, Im Neuenheimer Feld 220-221, 69120 Heildelberg, Germany.
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