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González LM, Bourissai A, Lessard-Beaudoin M, Lebel R, Tremblay L, Lepage M, Graham RK. Amelioration of Cognitive and Olfactory System Deficits in APOE4 Transgenic Mice with DHA Treatment. Mol Neurobiol 2023; 60:5624-5641. [PMID: 37329383 DOI: 10.1007/s12035-023-03401-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 05/24/2023] [Indexed: 06/19/2023]
Abstract
Olfactory dysfunction and atrophy of olfactory brain regions are observed early in mild cognitive impairment and Alzheimer disease. Despite substantial evidence showing neuroprotective effects in MCI/AD with treatment of docosahexaenoic acid (DHA), an omega-3 fatty acid, few studies have assessed DHA and its effects on the olfactory system deficits. We therefore performed structural (MRI), functional (olfactory behavior, novel object recognition), and molecular (markers of apoptosis and inflammation) assessments of APOE4 and wild-type mice ± DHA treatment at 3, 6, and 12 months of age. Our results demonstrate that APOE4 mice treated with the control diet show recognition memory deficits, abnormal olfactory habituation, and discrimination abilities and an increase in IBA-1 immunoreactivity in the olfactory bulb. These phenotypes were not present in APOE4 mice treated with a DHA diet. Alterations in some brain regions' weights and/or volumes were observed in the APOPE4 mice and may be due to caspase activation and/or neuroinflammatory events. These results suggest that the consumption of a diet rich in DHA may provide some benefit to E4 carriers but may not alleviate all symptoms.
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Affiliation(s)
- Laura Martínez González
- Research Centre on Aging CIUSSS de l'Estrie-CHUS, Sherbrooke, Quebec, Canada
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 3001 12e Avenue Nord, QC, J1H 5N4, Sherbrooke, Canada
| | - Adam Bourissai
- Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, Faculty of Medicine and Health Sciences, Sherbrooke, Quebec, J1H 5N4, Canada
| | - Mélissa Lessard-Beaudoin
- Research Centre on Aging CIUSSS de l'Estrie-CHUS, Sherbrooke, Quebec, Canada
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 3001 12e Avenue Nord, QC, J1H 5N4, Sherbrooke, Canada
| | - Réjean Lebel
- Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, Faculty of Medicine and Health Sciences, Sherbrooke, Quebec, J1H 5N4, Canada
| | - Luc Tremblay
- Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, Faculty of Medicine and Health Sciences, Sherbrooke, Quebec, J1H 5N4, Canada
| | - Martin Lepage
- Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, Faculty of Medicine and Health Sciences, Sherbrooke, Quebec, J1H 5N4, Canada
| | - Rona K Graham
- Research Centre on Aging CIUSSS de l'Estrie-CHUS, Sherbrooke, Quebec, Canada.
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 3001 12e Avenue Nord, QC, J1H 5N4, Sherbrooke, Canada.
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2
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Wang J, Chen P, Hu B, Cai F, Xu Q, Pan S, Wu Y, Song W. Distinct effects of SDC3 and FGFRL1 on selective neurodegeneration in AD and PD. FASEB J 2023; 37:e22773. [PMID: 36629784 DOI: 10.1096/fj.202201359r] [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: 08/18/2022] [Revised: 12/05/2022] [Accepted: 01/03/2023] [Indexed: 01/12/2023]
Abstract
Alzheimer's disease (AD) and Parkinson's disease (PD) are age-dependent neurodegenerative disorders. There is a profound neuronal loss in the basal forebrain cholinergic system in AD and severe dopaminergic deficiency within the nigrostriatal pathway in PD. Swedish APP (APPSWE ) and SNCAA53T mutations promote Aβ generation and α-synuclein aggregation, respectively, and have been linked to the pathogenesis of AD and PD. However, the mechanisms underlying selective cholinergic and dopaminergic neurodegeneration in AD and PD are still unknown. We demonstrated that APPSWE mutation enhanced Aβ generation and increased cell susceptibility to Aβ oligomer in cholinergic SN56 cells, whereas SNCAA53T mutations promoted aggregates formation and potentiated mutant α-synuclein oligomer-induced cytotoxicity in MN9D cells. Furthermore, syndecan-3 (SDC3) and fibroblast growth factor receptor-like 1 (FGFRL1) genes were differentially expressed in SN56 and MN9D cells carrying APPSWE or SNCAA53T mutation. SDC3 and FGFRL1 proteins were preferentially expressed in the cholinergic nucleus and dopaminergic neurons of APPSWE and SNCAA53T mouse models, respectively. Finally, the knockdown of SDC3 and FGFRL1 attenuated oxidative stress-induced cell death in SN56-APPSWE and MN9D-SNCAA53T cells. The results demonstrate that SDC3 and FGFRL1 mediated the specific effects of APPSWE and SNCAA53T on cholinergic and dopaminergic neurodegeneration in AD and PD, respectively. Our study suggests that SDC3 and FGFRL1 could be potential targets to alleviate the selective neurodegeneration in AD and PD.
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Affiliation(s)
- Juelu Wang
- Townsend Family Laboratories, Department of Psychiatry, Graduate Program in Neuroscience, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Peiye Chen
- Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, Zhejiang Provincial Clinical Research Center for Mental Disorders, School of Mental Health and the Affiliated Wenzhou Kangning Hospital, Wenzhou Medical University, Wenzhou, China.,Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, China
| | - Bolang Hu
- Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, Zhejiang Provincial Clinical Research Center for Mental Disorders, School of Mental Health and the Affiliated Wenzhou Kangning Hospital, Wenzhou Medical University, Wenzhou, China.,Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, China
| | - Fang Cai
- Townsend Family Laboratories, Department of Psychiatry, Graduate Program in Neuroscience, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Qin Xu
- Townsend Family Laboratories, Department of Psychiatry, Graduate Program in Neuroscience, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Sipei Pan
- Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, Zhejiang Provincial Clinical Research Center for Mental Disorders, School of Mental Health and the Affiliated Wenzhou Kangning Hospital, Wenzhou Medical University, Wenzhou, China.,Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, China
| | - Yili Wu
- Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, Zhejiang Provincial Clinical Research Center for Mental Disorders, School of Mental Health and the Affiliated Wenzhou Kangning Hospital, Wenzhou Medical University, Wenzhou, China.,Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, China
| | - Weihong Song
- Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, Zhejiang Provincial Clinical Research Center for Mental Disorders, School of Mental Health and the Affiliated Wenzhou Kangning Hospital, Wenzhou Medical University, Wenzhou, China.,Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, China
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3
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Solid-phase synthesis and pathological evaluation of pyroglutamate amyloid-β 3-42 peptide. Sci Rep 2023; 13:505. [PMID: 36627316 PMCID: PMC9831997 DOI: 10.1038/s41598-022-26616-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 12/16/2022] [Indexed: 01/11/2023] Open
Abstract
Pyroglutamate amyloid-β3-42 (AβpE3-42) is an N-terminally truncated and pyroglutamate-modified Aβ peptide retaining highly hydrophobic, amyloidogenic, and neurotoxic properties. In Alzheimer's disease (AD) patients, AβpE3-42 peptides accumulate into oligomers and induce cellular toxicity and synaptic dysfunction. AβpE3-42 aggregates further seed the formation of amyloid plaques, which are the pathological hallmarks of AD. Given that AβpE3-42 peptides play critical roles in the development of neurodegeneration, a reliable and reproducible synthetic access to these peptides may support pathological and medicinal studies of AD. Here, we synthesized AβpE3-42 peptides through the microwave-assisted solid-phase peptide synthesis (SPPS). Utilizing thioflavin T fluorescence assay and dot blotting analysis with anti-amyloid oligomer antibody, the amyloidogenic activity of synthesized AβpE3-42 peptides was confirmed. We further observed the cytotoxicity of AβpE3-42 aggregates in cell viability test. To examine the cognitive deficits induced by synthetic AβpE3-42 peptides, AβpE3-42 oligomers were intracerebroventricularly injected into imprinting control region mice and Y-maze and Morris water maze tests were performed. We found that AβpE3-42 aggregates altered the expression level of postsynaptic density protein 95 in cortical lysates. Collectively, we produced AβpE3-42 peptides in the microwave-assisted SPPS and evaluated the amyloidogenic and pathological function of the synthesized peptides.
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4
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Pyroglutamate Aβ cascade as drug target in Alzheimer's disease. Mol Psychiatry 2022; 27:1880-1885. [PMID: 34880449 PMCID: PMC9126800 DOI: 10.1038/s41380-021-01409-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/19/2021] [Accepted: 11/25/2021] [Indexed: 02/07/2023]
Abstract
One of the central aims in Alzheimer's disease (AD) research is the identification of clinically relevant drug targets. A plethora of potential molecular targets work very well in preclinical model systems both in vitro and in vivo in AD mouse models. However, the lack of translation into clinical settings in the AD field is a challenging endeavor. Although it is long known that N-terminally truncated and pyroglutamate-modified Abeta (AβpE3) peptides are abundantly present in the brain of AD patients, form stable and soluble low-molecular weight oligomers, and induce neurodegeneration in AD mouse models, their potential as drug target has not been generally accepted in the past. This situation has dramatically changed with the report that passive immunization with donanemab, an AβpE3-specific antibody, cleared aymloid plaques and stabilized cognitive deficits in a group of patients with mild AD in a phase II trial. This review summarizes the current knowledge on the molecular mechanisms of generation of AβpE, its biochemical properties, and the intervention points as a drug target in AD.
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Sompol P, Gollihue JL, Kraner SD, Artiushin IA, Cloyd RA, Chishti EA, Koren SA, Nation GK, Abisambra JF, Huzian O, Nagy LI, Santha M, Hackler L, Puskas LG, Norris CM. Q134R: Small chemical compound with NFAT inhibitory properties improves behavioral performance and synapse function in mouse models of amyloid pathology. Aging Cell 2021; 20:e13416. [PMID: 34117818 PMCID: PMC8282246 DOI: 10.1111/acel.13416] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 03/30/2021] [Accepted: 05/19/2021] [Indexed: 12/27/2022] Open
Abstract
Inhibition of the protein phosphatase calcineurin (CN) ameliorates pathophysiologic and cognitive changes in aging rodents and mice with aging-related Alzheimer's disease (AD)-like pathology. However, concerns over adverse effects have slowed the transition of common CN-inhibiting drugs to the clinic for the treatment of AD and AD-related disorders. Targeting substrates of CN, like the nuclear factor of activated T cells (NFATs), has been suggested as an alternative, safer approach to CN inhibitors. However, small chemical inhibitors of NFATs have only rarely been described. Here, we investigate a newly developed neuroprotective hydroxyquinoline derivative (Q134R) that suppresses NFAT signaling, without inhibiting CN activity. Q134R partially inhibited NFAT activity in primary rat astrocytes, but did not prevent CN-mediated dephosphorylation of a non-NFAT target, either in vivo, or in vitro. Acute (≤1 week) oral delivery of Q134R to APP/PS1 (12 months old) or wild-type mice (3-4 months old) infused with oligomeric Aβ peptides led to improved Y maze performance. Chronic (≥3 months) oral delivery of Q134R appeared to be safe, and, in fact, promoted survival in wild-type (WT) mice when given for many months beyond middle age. Finally, chronic delivery of Q134R to APP/PS1 mice during the early stages of amyloid pathology (i.e., between 6 and 9 months) tended to reduce signs of glial reactivity, prevented the upregulation of astrocytic NFAT4, and ameliorated deficits in synaptic strength and plasticity, without noticeably altering parenchymal Aβ plaque pathology. The results suggest that Q134R is a promising drug for treating AD and aging-related disorders.
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Affiliation(s)
- Pradoldej Sompol
- Sanders‐Brown Center on Aging University of Kentucky College of Medicine Lexington KY USA
| | - Jenna L. Gollihue
- Sanders‐Brown Center on Aging University of Kentucky College of Medicine Lexington KY USA
| | - Susan D. Kraner
- Sanders‐Brown Center on Aging University of Kentucky College of Medicine Lexington KY USA
| | - Irina A. Artiushin
- Sanders‐Brown Center on Aging University of Kentucky College of Medicine Lexington KY USA
| | - Ryan A. Cloyd
- Sanders‐Brown Center on Aging University of Kentucky College of Medicine Lexington KY USA
| | - Emad A. Chishti
- Sanders‐Brown Center on Aging University of Kentucky College of Medicine Lexington KY USA
| | - Shon A. Koren
- Sanders‐Brown Center on Aging University of Kentucky College of Medicine Lexington KY USA
| | - Grant K. Nation
- Sanders‐Brown Center on Aging University of Kentucky College of Medicine Lexington KY USA
| | - Jose F. Abisambra
- Center for Translational Research in Neurodegenerative Disease University of Florida Gainesville FL USA
| | | | | | | | | | | | - Christopher M. Norris
- Sanders‐Brown Center on Aging University of Kentucky College of Medicine Lexington KY USA
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6
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Rochais C, Lecoutey C, Hamidouche K, Giannoni P, Gaven F, Cem E, Mignani S, Baranger K, Freret T, Bockaert J, Rivera S, Boulouard M, Dallemagne P, Claeysen S. Donecopride, a Swiss army knife with potential against Alzheimer's disease. Br J Pharmacol 2020; 177:1988-2005. [PMID: 31881553 DOI: 10.1111/bph.14964] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 10/21/2019] [Accepted: 11/28/2019] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND AND PURPOSE We recently identified donecopride as a pleiotropic compound able to inhibit AChE and to activate 5-HT4 receptors. Here, we have assessed the potential therapeutic effects of donecopride in treating Alzheimer's disease (AD). EXPERIMENTAL APPROACH We used two in vivo animal models of AD, transgenic 5XFAD mice and mice exposed to soluble amyloid-β peptides and, in vitro, primary cultures of rat hippocampal neurons. Pro-cognitive and anti-amnesic effects were evaluated with novel object recognition, Y-maze, and Morris water maze tests. Amyloid load in mouse brain was measured ex vivo and effects of soluble amyloid-β peptides on neuronal survival and neurite formation determined in vitro. KEY RESULTS In vivo, chronic (3 months) administration of donecopride displayed potent anti-amnesic properties in the two mouse models of AD, preserving learning capacities, including working and long-term spatial memories. These behavioural effects were accompanied by decreased amyloid aggregation in the brain of 5XFAD mice and, in cultures of rat hippocampal neurons, reduced tau hyperphosphorylation. In vitro, donecopride increased survival in neuronal cultures exposed to soluble amyloid-β peptides, improved the neurite network and provided neurotrophic benefits, expressed as the formation of new synapses. CONCLUSIONS AND IMPLICATIONS Donecopride acts like a Swiss army knife, exhibiting a range of sustainable symptomatic therapeutic effects and potential disease-modifying effects in models of AD. Clinical trials with this promising drug candidate will soon be undertaken to confirm its therapeutic potential in humans.
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Affiliation(s)
- Christophe Rochais
- Normandie Univ, Caen, France.,UNICAEN, CERMN (Centre d'Etudes et de Recherche sur le Médicament de Normandie), Caen, France
| | - Cédric Lecoutey
- Normandie Univ, Caen, France.,UNICAEN, CERMN (Centre d'Etudes et de Recherche sur le Médicament de Normandie), Caen, France
| | - Katia Hamidouche
- Normandie Univ, Caen, France.,UNICAEN, INSERM U1075 COMETE, Caen, France
| | - Patrizia Giannoni
- IGF, Univ Montpellier, CNRS, INSERM, Montpellier, France.,Equipe Chrome, EA7352, Université de Nîmes, Nîmes, France
| | - Florence Gaven
- IGF, Univ Montpellier, CNRS, INSERM, Montpellier, France.,CRBM, CNRS UMR5237, Montpellier, France
| | - Eleazere Cem
- IGF, Univ Montpellier, CNRS, INSERM, Montpellier, France
| | - Serge Mignani
- Normandie Univ, Caen, France.,UNICAEN, CERMN (Centre d'Etudes et de Recherche sur le Médicament de Normandie), Caen, France
| | - Kevin Baranger
- Aix-Marseille Univ, CNRS, INP, Inst Neurophysiopathol, Marseille, France
| | - Thomas Freret
- Normandie Univ, Caen, France.,UNICAEN, INSERM U1075 COMETE, Caen, France
| | - Joël Bockaert
- IGF, Univ Montpellier, CNRS, INSERM, Montpellier, France
| | - Santiago Rivera
- Aix-Marseille Univ, CNRS, INP, Inst Neurophysiopathol, Marseille, France
| | - Michel Boulouard
- Normandie Univ, Caen, France.,UNICAEN, INSERM U1075 COMETE, Caen, France
| | - Patrick Dallemagne
- Normandie Univ, Caen, France.,UNICAEN, CERMN (Centre d'Etudes et de Recherche sur le Médicament de Normandie), Caen, France
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Wang LS, Tao X, Liu XM, Zhou YF, Zhang MD, Liao YH, Pan RL, Chang Q. Cajaninstilbene Acid Ameliorates Cognitive Impairment Induced by Intrahippocampal Injection of Amyloid-β 1-42 Oligomers. Front Pharmacol 2019; 10:1084. [PMID: 31680939 PMCID: PMC6798059 DOI: 10.3389/fphar.2019.01084] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 08/26/2019] [Indexed: 12/18/2022] Open
Abstract
Amyloid-β1-42 (Aβ1-42) oligomers play an important role at the early stage of Alzheimer's disease (AD) and have been a vital target in the development of therapeutic drugs for AD. Cajaninstilbene acid (CSA), a major bioactive stilbene isolated from pigeon pea (Cajanus cajan) leaves, exerted the neuroprotective property in our previous studies. The present study utilized a validated mouse model of early-stage AD induced by bilateral injection of Aβ1-42 oligomers into hippocampal CA1 regions (100 pmol/mouse) to investigate the cognitive enhancing effects of CSA and the underlying mechanism, by a combination of animal behavioral tests, immunohistochemistry, liquid chromatography-tandem mass spectrometry analysis, and Western blot methods. Intragastric administration of CSA (7.5, 15, and 30 mg/kg) attenuated the impairment of learning and memory induced by Aβ1-42 oligomers. CSA stimulated Aβ clearance and prevented microglial activation and astrocyte reactivity in the hippocampus of model mice. It also decreased the high levels of Glu but increased the low levels of GABA. In addition, CSA inhibited excessive expression of GluN2B-containing NMDARs and upregulated the downstream PKA/CREB/BDNF/TrkB signaling pathway. These results suggest that CSA could be a potential therapeutic agent at the early stage of AD.
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Affiliation(s)
- Li-Sha Wang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xue Tao
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xin-Min Liu
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,National Key Laboratory of Human Factors Engineering and the State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Yun-Feng Zhou
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Meng-Di Zhang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yong-Hong Liao
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Rui-Le Pan
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Qi Chang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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8
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Olfactory bulb atrophy and caspase activation observed in the BACHD rat models of Huntington disease. Neurobiol Dis 2019; 125:219-231. [DOI: 10.1016/j.nbd.2019.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 12/14/2018] [Accepted: 02/04/2019] [Indexed: 01/08/2023] Open
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9
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Watremez W, Jackson J, Almari B, McLean SL, Grayson B, Neill JC, Fischer N, Allouche A, Koziel V, Pillot T, Harte MK. Stabilized Low-n Amyloid-β Oligomers Induce Robust Novel Object Recognition Deficits Associated with Inflammatory, Synaptic, and GABAergic Dysfunction in the Rat. J Alzheimers Dis 2019; 62:213-226. [PMID: 29439327 DOI: 10.3233/jad-170489] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND With current treatments for Alzheimer's disease (AD) only providing temporary symptomatic benefits, disease modifying drugs are urgently required. This approach relies on improved understanding of the early pathophysiology of AD. A new hypothesis has emerged, in which early memory loss is considered a synapse failure caused by soluble amyloid-β oligomers (Aβo). These small soluble Aβo, which precede the formation of larger fibrillar assemblies, may be the main cause of early AD pathologies. OBJECTIVE The aim of the current study was to investigate the effect of acute administration of stabilized low-n amyloid-β1-42 oligomers (Aβo1-42) on cognitive, inflammatory, synaptic, and neuronal markers in the rat. METHODS Female and male Lister Hooded rats received acute intracerebroventricular (ICV) administration of either vehicle or 5 nmol of Aβo1-42 (10μL). Cognition was assessed in the novel object recognition (NOR) paradigm at different time points. Levels of inflammatory (IL-1β, IL-6, TNF-α), synaptic (PSD-95, SNAP-25), and neuronal (n-acetylaspartate, parvalbumin-positive cells) markers were investigated in different brain regions (prefrontal and frontal cortex, striatum, dorsal and ventral hippocampus). RESULTS Acute ICV administration of Aβo1-42 induced robust and enduring NOR deficits. These deficits were reversed by acute administration of donepezil and rolipram but not risperidone. Postmortem analysis revealed an increase in inflammatory markers, a decrease in synaptic markers and parvalbumin containing interneurons in the frontal cortex, with no evidence of widespread neuronal loss. CONCLUSION Taken together the results suggest that acute administration of soluble low-n Aβo may be a useful model to study the early mechanisms involved in AD and provide us with a platform for testing novel therapeutic approaches that target the early underlying synaptic pathology.
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Affiliation(s)
- William Watremez
- Division of Pharmacy and Optometry, University of Manchester, Manchester, UK
| | - Joshua Jackson
- Division of Pharmacy and Optometry, University of Manchester, Manchester, UK
| | - Bushra Almari
- Division of Pharmacy and Optometry, University of Manchester, Manchester, UK
| | - Samantha L McLean
- School of Pharmacy and Medical Sciences, University of Bradford, Bradford, UK
| | - Ben Grayson
- Division of Pharmacy and Optometry, University of Manchester, Manchester, UK
| | - Joanna C Neill
- Division of Pharmacy and Optometry, University of Manchester, Manchester, UK
| | - Nicolas Fischer
- SynAging, Institut Polytechnique National de Lorraine, Vandoeuvre-lès-Nancy, France
| | - Ahmad Allouche
- SynAging, Institut Polytechnique National de Lorraine, Vandoeuvre-lès-Nancy, France
| | - Violette Koziel
- SynAging, Institut Polytechnique National de Lorraine, Vandoeuvre-lès-Nancy, France
| | - Thierry Pillot
- SynAging, Institut Polytechnique National de Lorraine, Vandoeuvre-lès-Nancy, France
| | - Michael K Harte
- Division of Pharmacy and Optometry, University of Manchester, Manchester, UK
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10
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Roher AE, Kokjohn TA, Clarke SG, Sierks MR, Maarouf CL, Serrano GE, Sabbagh MS, Beach TG. APP/Aβ structural diversity and Alzheimer's disease pathogenesis. Neurochem Int 2017; 110:1-13. [PMID: 28811267 PMCID: PMC5688956 DOI: 10.1016/j.neuint.2017.08.007] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/25/2017] [Accepted: 08/11/2017] [Indexed: 02/01/2023]
Abstract
The amyloid cascade hypothesis of Alzheimer's disease (AD) proposes amyloid- β (Aβ) is a chief pathological element of dementia. AD therapies have targeted monomeric and oligomeric Aβ 1-40 and 1-42 peptides. However, alternative APP proteolytic processing produces a complex roster of Aβ species. In addition, Aβ peptides are subject to extensive posttranslational modification (PTM). We propose that amplified production of some APP/Aβ species, perhaps exacerbated by differential gene expression and reduced peptide degradation, creates a diverse spectrum of modified species which disrupt brain homeostasis and accelerate AD neurodegeneration. We surveyed the literature to catalog Aβ PTM including species with isoAsp at positions 7 and 23 which may phenocopy the Tottori and Iowa Aβ mutations that result in early onset AD. We speculate that accumulation of these alterations induce changes in secondary and tertiary structure of Aβ that favor increased toxicity, and seeding and propagation in sporadic AD. Additionally, amyloid-β peptides with a pyroglutamate modification at position 3 and oxidation of Met35 make up a substantial portion of sporadic AD amyloid deposits. The intrinsic physical properties of these species, including resistance to degradation, an enhanced aggregation rate, increased neurotoxicity, and association with behavioral deficits, suggest their emergence is linked to dementia. The generation of specific 3D-molecular conformations of Aβ impart unique biophysical properties and a capacity to seed the prion-like global transmission of amyloid through the brain. The accumulation of rogue Aβ ultimately contributes to the destruction of vascular walls, neurons and glial cells culminating in dementia. A systematic examination of Aβ PTM and the analysis of the toxicity that they induced may help create essential biomarkers to more precisely stage AD pathology, design countermeasures and gauge the impacts of interventions.
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Affiliation(s)
- Alex E Roher
- Division of Neurobiology, Barrow Neurological Institute, Phoenix, AZ 85013, USA; Division of Clinical Education, Midwestern University, Glendale, AZ 85308, USA.
| | - Tyler A Kokjohn
- Department of Microbiology, Midwestern University, Glendale, AZ 85308, USA
| | - Steven G Clarke
- Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California, Los Angeles, Los Angeles CA 90095-1569, USA
| | - Michael R Sierks
- Department of Chemical Engineering, Arizona State University, Tempe, AZ 85287-6106, USA
| | - Chera L Maarouf
- Laboratory of Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA
| | - Geidy E Serrano
- Laboratory of Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA
| | - Marwan S Sabbagh
- Alzheimer's and Memory Disorders Division, Barrow Neurological Institute, Phoenix, AZ 85013, USA
| | - Thomas G Beach
- Laboratory of Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA
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11
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Thomas MH, Paris C, Magnien M, Colin J, Pelleïeux S, Coste F, Escanyé MC, Pillot T, Olivier JL. Dietary arachidonic acid increases deleterious effects of amyloid-β oligomers on learning abilities and expression of AMPA receptors: putative role of the ACSL4-cPLA 2 balance. ALZHEIMERS RESEARCH & THERAPY 2017; 9:69. [PMID: 28851448 PMCID: PMC5576249 DOI: 10.1186/s13195-017-0295-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 08/03/2017] [Indexed: 01/14/2023]
Abstract
Background Polyunsaturated fatty acids play a crucial role in neuronal function, and the modification of these compounds in the brain could have an impact on neurodegenerative diseases such as Alzheimer’s disease. Despite the fact that arachidonic acid is the second foremost polyunsaturated fatty acid besides docosahexaenoic acid, its role and the regulation of its transfer and mobilization in the brain are poorly known. Methods Two groups of 39 adult male BALB/c mice were fed with an arachidonic acid-enriched diet or an oleic acid-enriched diet, respectively, for 12 weeks. After 10 weeks on the diet, mice received intracerebroventricular injections of either NaCl solution or amyloid-β peptide (Aβ) oligomers. Y-maze and Morris water maze tests were used to evaluate short- and long-term memory. At 12 weeks on the diet, mice were killed, and blood, liver, and brain samples were collected for lipid and protein analyses. Results We found that the administration of an arachidonic acid-enriched diet for 12 weeks induced short-term memory impairment and increased deleterious effects of Aβ oligomers on learning abilities. These cognitive alterations were associated with modifications of expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors, postsynaptic density protein 95, and glial fibrillary acidic protein in mouse cortex or hippocampus by the arachidonic acid-enriched diet and Aβ oligomer administration. This diet also led to an imbalance between the main ω-6 fatty acids and the ω-3 fatty acids in favor of the first one in erythrocytes and the liver as well as in the hippocampal and cortical brain structures. In the cortex, the dietary arachidonic acid also induced an increase of arachidonic acid-containing phospholipid species in phosphatidylserine class, whereas intracerebroventricular injections modified several arachidonic acid- and docosahexaenoic acid-containing species in the four phospholipid classes. Finally, we observed that dietary arachidonic acid decreased the expression of the neuronal form of acyl-coenzyme A synthetase 4 in the hippocampus and increased the cytosolic phospholipase A2 activation level in the cortices of the mice. Conclusions Dietary arachidonic acid could amplify Aβ oligomer neurotoxicity. Its consumption could constitute a risk factor for Alzheimer’s disease in humans and should be taken into account in future preventive strategies. Its deleterious effect on cognitive capacity could be linked to the balance between arachidonic acid-mobilizing enzymes. Electronic supplementary material The online version of this article (doi:10.1186/s13195-017-0295-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mélanie H Thomas
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France
| | - Cédric Paris
- Laboratory of Biomolecules Engineering (LIBio), Lorraine University, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France
| | - Mylène Magnien
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France
| | - Julie Colin
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France
| | - Sandra Pelleïeux
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France.,Biochemistry Department, Central Hospital, University Hospitals of Nancy, 24, avenue du Mal de Lattre de Tassigny, CO n°34, F-54018, Nancy, France
| | - Florence Coste
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France
| | - Marie-Christine Escanyé
- Biochemistry Department, Central Hospital, University Hospitals of Nancy, 24, avenue du Mal de Lattre de Tassigny, CO n°34, F-54018, Nancy, France
| | - Thierry Pillot
- Synaging SAS, 2, rue du Doyen Marcel Roubault, 54518, Vandoeuvre-les-Nancy, France
| | - Jean-Luc Olivier
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France. .,Biochemistry Department, Central Hospital, University Hospitals of Nancy, 24, avenue du Mal de Lattre de Tassigny, CO n°34, F-54018, Nancy, France.
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12
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Piechotta A, Parthier C, Kleinschmidt M, Gnoth K, Pillot T, Lues I, Demuth HU, Schilling S, Rahfeld JU, Stubbs MT. Structural and functional analyses of pyroglutamate-amyloid-β-specific antibodies as a basis for Alzheimer immunotherapy. J Biol Chem 2017; 292:12713-12724. [PMID: 28623233 PMCID: PMC5535044 DOI: 10.1074/jbc.m117.777839] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 06/07/2017] [Indexed: 12/22/2022] Open
Abstract
Alzheimer disease is associated with deposition of the amyloidogenic peptide Aβ in the brain. Passive immunization using Aβ-specific antibodies has been demonstrated to reduce amyloid deposition both in vitro and in vivo Because N-terminally truncated pyroglutamate (pE)-modified Aβ species (AβpE3) exhibit enhanced aggregation potential and propensity to form toxic oligomers, they represent particularly attractive targets for antibody therapy. Here we present three separate monoclonal antibodies that specifically recognize AβpE3 with affinities of 1-10 nm and inhibit AβpE3 fibril formation in vitro. In vivo application of one of these resulted in improved memory in AβpE3 oligomer-treated mice. Crystal structures of Fab-AβpE3 complexes revealed two distinct binding modes for the peptide. Juxtaposition of pyroglutamate pE3 and the F4 side chain (the "pEF head") confers a pronounced bulky hydrophobic nature to the AβpE3 N terminus that might explain the enhanced aggregation properties of the modified peptide. The deep burial of the pEF head by two of the antibodies explains their high target specificity and low cross-reactivity, making them promising candidates for the development of clinical antibodies.
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Affiliation(s)
- Anke Piechotta
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Institute of Biotechnology, Martin Luther University, 06108 Halle-Wittenberg, Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany
| | - Christoph Parthier
- Institute of Biotechnology, Martin Luther University, 06108 Halle-Wittenberg, Germany
| | - Martin Kleinschmidt
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany
| | - Kathrin Gnoth
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany
| | | | - Inge Lues
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany
| | - Hans-Ulrich Demuth
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany
| | - Stephan Schilling
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany
| | - Jens-Ulrich Rahfeld
- Probiodrug AG, Weinbergweg 22, 06120 Halle (Saale), Germany; Department of Molecular Drug Biochemistry and Therapy, Fraunhofer Institute for Cell Therapy and Immunology, Weinbergweg 22, 06120 Halle, Germany.
| | - Milton T Stubbs
- Institute of Biotechnology, Martin Luther University, 06108 Halle-Wittenberg, Germany.
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13
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Colin J, Allouche A, Chauveau F, Corbier C, Pauron-Gregory L, Lanhers MC, Claudepierre T, Yen FT, Oster T, Malaplate-Armand C. Improved Neuroprotection Provided by Drug Combination in Neurons Exposed to Cell-Derived Soluble Amyloid-β Peptide. J Alzheimers Dis 2017; 52:975-87. [PMID: 27163806 DOI: 10.3233/jad-151110] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Oligomeric amyloid-β (Aβ) peptide contributes to impaired synaptic connections and neurodegenerative processes, and as such, represents a primary therapeutic target for Alzheimer's disease (AD)-modifying approaches. However, the lack of efficacy of drugs that inhibit production of Aβ demonstrates the need for a better characterization of its toxic effects, both on synaptic and neuronal function. Here, we used conditioned medium obtained from recombinant HEK-AβPP cells expressing the human amyloid-β protein precursor (Aβ-CM), to investigate Aβ-induced neurotoxic and synaptotoxic effects. Characterization of Aβ-CM revealed that it contained picomolar amounts of cell-secreted Aβ in its soluble form. Incubation of primary cortical neurons with Aβ-CM led to significant decreases in synaptic protein levels as compared to controls. This effect was no longer observed in neurons incubated with conditioned medium obtained from HEK-AβPP cells grown in presence of the γ-secretase inhibitor, Semagacestat or LY450139 (LY-CM). However, neurotoxic and pro-apoptotic effects of Aβ-CM were only partially prevented using LY-CM, which could be explained by other deleterious compounds related to chronic oxidative stress that were released by HEK-AβPP cells. Indeed, full neuroprotection was observed in cells exposed to LY-CM by additional treatment with the antioxidant resveratrol, or with the pluripotent n-3 polyunsaturated fatty acid docosahexaenoic acid. Inhibition of Aβ production appeared necessary but insufficient to prevent neurodegenerative effects associated with AD due to other neurotoxic compounds that could exert additional deleterious effects on neuronal function and survival. Therefore, association of various types of protective agents needs to be considered when developing strategies for AD treatment.
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Affiliation(s)
- Julie Colin
- Université de Lorraine, ENSAIA, UR AFPA, EA 3998, USC INRA 0340, Nancy, France
| | - Ahmad Allouche
- Université de Lorraine, ENSAIA, UR AFPA, EA 3998, USC INRA 0340, Nancy, France
| | - Fabien Chauveau
- Université de Lyon 1, Lyon Neuroscience Research Center; CNRS UMR5292; INSERM U1028; Lyon, France
| | - Catherine Corbier
- Université de Lorraine, ENSAIA, UR AFPA, EA 3998, USC INRA 0340, Nancy, France
| | - Lynn Pauron-Gregory
- Université de Lorraine, ENSAIA, UR AFPA, EA 3998, USC INRA 0340, Nancy, France
| | | | - Thomas Claudepierre
- Université de Lorraine, ENSAIA, UR AFPA, EA 3998, USC INRA 0340, Nancy, France
| | - Frances T Yen
- Université de Lorraine, ENSAIA, UR AFPA, EA 3998, USC INRA 0340, Nancy, France
| | - Thierry Oster
- Université de Lorraine, ENSAIA, UR AFPA, EA 3998, USC INRA 0340, Nancy, France
| | - Catherine Malaplate-Armand
- Université de Lorraine, ENSAIA, UR AFPA, EA 3998, USC INRA 0340, Nancy, France.,Laboratoire de Biochimie, Hôpital Central, CHU de Nancy, CO n°34, Nancy, France
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14
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Goldblatt G, Cilenti L, Matos JO, Lee B, Ciaffone N, Wang QX, Tetard L, Teter K, Tatulian SA. Unmodified and pyroglutamylated amyloid β peptides form hypertoxic hetero-oligomers of unique secondary structure. FEBS J 2017; 284:1355-1369. [PMID: 28294556 DOI: 10.1111/febs.14058] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 03/07/2017] [Accepted: 03/08/2017] [Indexed: 11/29/2022]
Abstract
Amyloid β (Aβ) peptide plays a major role in Alzheimer's disease (AD) and occurs in multiple forms, including pyroglutamylated Aβ (AβpE). Identification and characterization of the most cytotoxic Aβ species is necessary for advancement in AD diagnostics and therapeutics. While in brain tissue multiple Aβ species act in combination, structure/toxicity studies and immunotherapy trials have been focused on individual forms of Aβ. As a result, the molecular composition and the structural features of "toxic Aβ oligomers" have remained unresolved. Here, we have used a novel approach, hydration from gas phase coupled with isotope-edited Fourier transform infrared (FTIR) spectroscopy, to identify the prefibrillar assemblies formed by Aβ and AβpE and to resolve the structures of both peptides in combination. The peptides form unusual β-sheet oligomers stabilized by intramolecular H-bonding as opposed to intermolecular H-bonding in the fibrils. Time-dependent morphological changes in peptide assemblies have been visualized by atomic force microscopy. Aβ/AβpE hetero-oligomers exert unsurpassed cytotoxic effect on PC12 cells as compared to oligomers of individual peptides or fibrils. These findings lead to a novel concept that Aβ/AβpE hetero-oligomers, not just Aβ or AβpE oligomers, constitute the main neurotoxic conformation. The hetero-oligomers thus present a new biomarker that may be targeted for development of more efficient diagnostic and immunotherapeutic strategies to combat AD.
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Affiliation(s)
- Greg Goldblatt
- Biomedical Sciences Graduate Program, University of Central Florida, Orlando, FL, USA
| | - Lucia Cilenti
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Jason O Matos
- Biotechnology Graduate Program, University of Central Florida, Orlando, FL, USA
| | - Briana Lee
- Nanotechnology Graduate Program, NanoScience Technology Center, University of Central Florida, Orlando, FL, USA
| | - Nicholas Ciaffone
- Nanotechnology Graduate Program, NanoScience Technology Center, University of Central Florida, Orlando, FL, USA
| | - Qing X Wang
- Physics Graduate Program, College of Sciences, University of Central Florida, Orlando, FL, USA
| | - Laurene Tetard
- NanoScience Technology Center, University of Central Florida, Orlando, FL, USA.,Department of Physics, College of Sciences, University of Central Florida, Orlando, FL, USA
| | - Ken Teter
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Suren A Tatulian
- Department of Physics, College of Sciences, University of Central Florida, Orlando, FL, USA
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15
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Nie J, Tian Y, Zhang Y, Lu YL, Li LS, Shi JS. Dendrobium alkaloids prevent Aβ 25-35-induced neuronal and synaptic loss via promoting neurotrophic factors expression in mice. PeerJ 2016; 4:e2739. [PMID: 27994964 PMCID: PMC5157189 DOI: 10.7717/peerj.2739] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 10/25/2016] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Neuronal and synaptic loss is the most important risk factor for cognitive impairment. Inhibiting neuronal apoptosis and preventing synaptic loss are promising therapeutic approaches for Alzheimer's disease (AD). In this study, we investigate the protective effects of Dendrobium alkaloids (DNLA), a Chinese medicinal herb extract, on β-amyloid peptide segment 25-35 (Aβ25-35)-induced neuron and synaptic loss in mice. METHOD Aβ25-35(10 µg) was injected into the bilateral ventricles of male mice followed by an oral administration of DNLA (40 mg/kg) for 19 days. The Morris water maze was used for evaluating the ability of spatial learning and memory function of mice. The morphological changes were examined via H&E staining and Nissl staining. TUNEL staining was used to check the neuronal apoptosis. The ultrastructure changes of neurons were observed under electron microscope. Western blot was used to evaluate the protein expression levels of ciliary neurotrophic factor (CNTF), glial cell line-derived neurotrophic factor (GDNF), and brain-derived neurotrophic factor (BDNF) in the hippocampus and cortex. RESULTS DNLA significantly attenuated Aβ25-35-induced spatial learning and memory impairments in mice. DNLA prevented Aβ25-35-induced neuronal loss in the hippocampus and cortex, increased the number of Nissl bodies, improved the ultrastructural injury of neurons and increased the number of synapses in neurons. Furthermore, DNLA increased the protein expression of neurotrophic factors BDNF, CNTF and GDNF in the hippocampus and cortex. CONCLUSIONS DNLA can prevent neuronal apoptosis and synaptic loss. This effect is mediated at least in part via increasing the expression of BDNF, GDNF and CNTF in the hippocampus and cortex; improving Aβ-induced spatial learning and memory impairment in mice.
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Affiliation(s)
- Jing Nie
- Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Pharmacology and the Key Laboratory of Basic Pharmacology of Guizhou Province, Zunyi Medical College, Zunyi, Guizhou Province, China
| | - Yong Tian
- Department of Pharmacology and the Key Laboratory of Basic Pharmacology of Guizhou Province, Zunyi Medical College , Zunyi , Guizhou Province , China
| | - Yu Zhang
- Department of Pharmacology and the Key Laboratory of Basic Pharmacology of Guizhou Province, Zunyi Medical College , Zunyi , Guizhou Province , China
| | - Yan-Liu Lu
- Department of Pharmacology and the Key Laboratory of Basic Pharmacology of Guizhou Province, Zunyi Medical College , Zunyi , Guizhou Province , China
| | - Li-Sheng Li
- Department of Pharmacology and the Key Laboratory of Basic Pharmacology of Guizhou Province, Zunyi Medical College , Zunyi , Guizhou Province , China
| | - Jing-Shan Shi
- Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Pharmacology and the Key Laboratory of Basic Pharmacology of Guizhou Province, Zunyi Medical College, Zunyi, Guizhou Province, China
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16
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Daniels MJD, Rivers-Auty J, Schilling T, Spencer NG, Watremez W, Fasolino V, Booth SJ, White CS, Baldwin AG, Freeman S, Wong R, Latta C, Yu S, Jackson J, Fischer N, Koziel V, Pillot T, Bagnall J, Allan SM, Paszek P, Galea J, Harte MK, Eder C, Lawrence CB, Brough D. Fenamate NSAIDs inhibit the NLRP3 inflammasome and protect against Alzheimer's disease in rodent models. Nat Commun 2016; 7:12504. [PMID: 27509875 PMCID: PMC4987536 DOI: 10.1038/ncomms12504] [Citation(s) in RCA: 309] [Impact Index Per Article: 38.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 07/06/2016] [Indexed: 12/13/2022] Open
Abstract
Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit cyclooxygenase-1 (COX-1) and COX-2 enzymes. The NLRP3 inflammasome is a multi-protein complex responsible for the processing of the proinflammatory cytokine interleukin-1β and is implicated in many inflammatory diseases. Here we show that several clinically approved and widely used NSAIDs of the fenamate class are effective and selective inhibitors of the NLRP3 inflammasome via inhibition of the volume-regulated anion channel in macrophages, independently of COX enzymes. Flufenamic acid and mefenamic acid are efficacious in NLRP3-dependent rodent models of inflammation in air pouch and peritoneum. We also show therapeutic effects of fenamates using a model of amyloid beta induced memory loss and a transgenic mouse model of Alzheimer's disease. These data suggest that fenamate NSAIDs could be repurposed as NLRP3 inflammasome inhibitors and Alzheimer's disease therapeutics.
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Affiliation(s)
- Michael J. D. Daniels
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - Jack Rivers-Auty
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - Tom Schilling
- St. George's University of London, Institute for Infection and Immunity, Cranmer Terrace, London SW17 0RE, UK
| | - Nicholas G. Spencer
- St. George's University of London, Institute for Infection and Immunity, Cranmer Terrace, London SW17 0RE, UK
| | - William Watremez
- Manchester Pharmacy School, University of Manchester, Manchester M13 9PT, UK
| | - Victoria Fasolino
- Manchester Pharmacy School, University of Manchester, Manchester M13 9PT, UK
| | - Sophie J. Booth
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - Claire S. White
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - Alex G. Baldwin
- Manchester Pharmacy School, University of Manchester, Manchester M13 9PT, UK
| | - Sally Freeman
- Manchester Pharmacy School, University of Manchester, Manchester M13 9PT, UK
| | - Raymond Wong
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - Clare Latta
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - Shi Yu
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - Joshua Jackson
- Manchester Pharmacy School, University of Manchester, Manchester M13 9PT, UK
| | | | | | | | - James Bagnall
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - Stuart M. Allan
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - Pawel Paszek
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - James Galea
- Division of Neuroscience, Ninewells Medical School, University of Dundee, Dundee DD1 9SY, UK
| | - Michael K. Harte
- Manchester Pharmacy School, University of Manchester, Manchester M13 9PT, UK
| | - Claudia Eder
- St. George's University of London, Institute for Infection and Immunity, Cranmer Terrace, London SW17 0RE, UK
| | - Catherine B. Lawrence
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
| | - David Brough
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Oxford Road, Manchester M13 9PT, UK
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Piromelatine ameliorates memory deficits associated with chronic mild stress-induced anhedonia in rats. Psychopharmacology (Berl) 2016; 233:2229-39. [PMID: 27007604 DOI: 10.1007/s00213-016-4272-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Accepted: 03/08/2016] [Indexed: 12/15/2022]
Abstract
RATIONALE Previous studies have demonstrated that piromelatine (a melatonin and serotonin 5-HT1A and 5-HT1D agonist) exerts an antidepressant activity in rodent models of acute stress and improves cognitive impairments in a rat model of Alzheimer's disease (AD). However, the role of piromelatine in chronic stress-induced memory dysfunction remains unclear. OBJECTIVE The aim of this study was to determine whether piromelatine ameliorates chronic mild stress (CMS)-induced memory deficits and explore the underlying mechanisms. METHODS Rats were exposed randomly to chronic mild stressors for 7 weeks to induce anhedonia (reflected by a significant decrease in sucrose intake), which was used to select rats vulnerable (CMS-anhedonic, CMSA) or resistant (CMS-resistant, CMSR) to stress. Piromelatine (50 mg/kg) was administered daily during the last 2 weeks of CMS. The tail suspension and forced swimming tests were adopted to further characterize vulnerable and resilient rats. The Y-maze and novel object recognition (NOR) tests were used to evaluate memory performance. Brain-derived neurotrophic factor (BDNF), cAMP response element-binding protein (CREB), phosphorylated CREB (pCREB), and cytogenesis were measured in the hippocampus. RESULTS We found that only CMSA rats displayed significant increases in immobility time in the tail suspension and forced swimming tests; memory deficits in the Y-maze and NOR tests; significant decreases in hippocampal BDNF, CREB, and pCREB expression; and cytogenesis. All these anhedonia-associated effects were reversed by piromelatine. CONCLUSIONS Piromelatine ameliorates memory deficits associated with CMS-induced anhedonia in rats and this effect may be mediated by restoring hippocampal BDNF, CREB, and cytogenesis deficits.
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18
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Nagel-Steger L, Owen MC, Strodel B. An Account of Amyloid Oligomers: Facts and Figures Obtained from Experiments and Simulations. Chembiochem 2016; 17:657-76. [PMID: 26910367 DOI: 10.1002/cbic.201500623] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Indexed: 12/27/2022]
Abstract
The deposition of amyloid in brain tissue in the context of neurodegenerative diseases involves the formation of intermediate species-termed oligomers-of lower molecular mass and with structures that deviate from those of mature amyloid fibrils. Because these oligomers are thought to be primarily responsible for the subsequent disease pathogenesis, the elucidation of their structure is of enormous interest. Nevertheless, because of the high aggregation propensity and the polydispersity of oligomeric species formed by the proteins or peptides in question, the preparation of appropriate samples for high-resolution structural methods has proven to be rather difficult. This is why theoretical approaches have been of particular importance in gaining insights into possible oligomeric structures for some time. Only recently has it been possible to achieve some progress with regard to the experimentally based structural characterization of defined oligomeric species. Here we discuss how theory and experiment are used to determine oligomer structures and what can be done to improve the integration of the two disciplines.
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Affiliation(s)
- Luitgard Nagel-Steger
- Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany.,Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätstrasse 1, 40225, Düsseldorf, Germany
| | - Michael C Owen
- Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Birgit Strodel
- Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany. .,Institute of Theoretical and Computational Chemistry, Heinrich Heine University Düsseldorf, Universitätstrasse 1, 40225, Düsseldorf, Germany.
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The antineoplastic drug flavopiridol reverses memory impairment induced by Amyloid-ß1-42 oligomers in mice. Pharmacol Res 2016; 106:10-20. [PMID: 26875816 DOI: 10.1016/j.phrs.2016.02.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Revised: 02/03/2016] [Accepted: 02/05/2016] [Indexed: 01/06/2023]
Abstract
The ectopic re-activation of cell cycle in neurons is an early event in the pathogenesis of Alzheimer's disease (AD), which could lead to synaptic failure and ensuing cognitive deficits before frank neuronal death. Cytostatic drugs that act as cyclin-dependent kinase (CDK) inhibitors have been poorly investigated in animal models of AD. In the present study, we examined the effects of flavopiridol, an inhibitor of CDKs currently used as antineoplastic drug, against cell cycle reactivation and memory loss induced by intracerebroventricular injection of Aß1-42 oligomers in CD1 mice. Cycling neurons, scored as NeuN-positive cells expressing cyclin A, were found both in the frontal cortex and in the hippocampus of Aβ-injected mice, paralleling memory deficits. Starting from three days after Aβ injection, flavopiridol (0.5, 1 and 3mg/kg) was intraperitoneally injected daily, for eleven days. Here we show that a treatment with flavopiridol (0.5 and 1mg/kg) was able to rescue the loss of memory induced by Aβ1-42, and to prevent the occurrence of ectopic cell-cycle events in the mouse frontal cortex and hippocampus. This is the first evidence that a cytostatic drug can prevent cognitive deficits in a non-transgenic animal model of AD.
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Immunotherapy Against N-Truncated Amyloid-β Oligomers. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2016. [DOI: 10.1007/978-1-4939-3560-4_3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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21
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Gunn AP, Wong BX, Johanssen T, Griffith JC, Masters CL, Bush AI, Barnham KJ, Duce JA, Cherny RA. Amyloid-β Peptide Aβ3pE-42 Induces Lipid Peroxidation, Membrane Permeabilization, and Calcium Influx in Neurons. J Biol Chem 2015; 291:6134-45. [PMID: 26697885 DOI: 10.1074/jbc.m115.655183] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Indexed: 12/19/2022] Open
Abstract
Pyroglutamate-modified amyloid-β (pE-Aβ) is a highly neurotoxic amyloid-β (Aβ) isoform and is enriched in the brains of individuals with Alzheimer disease compared with healthy aged controls. Pyroglutamate formation increases the rate of Aβ oligomerization and alters the interactions of Aβ with Cu(2+) and lipids; however, a link between these properties and the toxicity of pE-Aβ peptides has not been established. We report here that Aβ3pE-42 has an enhanced capacity to cause lipid peroxidation in primary cortical mouse neurons compared with the full-length isoform (Aβ(1-42)). In contrast, Aβ(1-42) caused a significant elevation in cytosolic reactive oxygen species, whereas Aβ3pE-42 did not. We also report that Aβ3pE-42 preferentially associates with neuronal membranes and triggers Ca(2+) influx that can be partially blocked by the N-methyl-d-aspartate receptor antagonist MK-801. Aβ3pE-42 further caused a loss of plasma membrane integrity and remained bound to neurons at significantly higher levels than Aβ(1-42) over extended incubations. Pyroglutamate formation was additionally found to increase the relative efficiency of Aβ-dityrosine oligomer formation mediated by copper-redox cycling.
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Affiliation(s)
- Adam P Gunn
- From the Florey Institute of Neuroscience and Mental Health
| | - Bruce X Wong
- From the Florey Institute of Neuroscience and Mental Health
| | | | - James C Griffith
- Materials Characterisation and Fabrication Platform, University of Melbourne, Parkville, Melbourne 3010, Australia and
| | | | - Ashley I Bush
- From the Florey Institute of Neuroscience and Mental Health, Departments of Pathology and
| | - Kevin J Barnham
- From the Florey Institute of Neuroscience and Mental Health, Pharmacology and Therapeutics, and
| | - James A Duce
- From the Florey Institute of Neuroscience and Mental Health, Departments of Pathology and the School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire LS2 9JT, United Kingdom
| | - Robert A Cherny
- From the Florey Institute of Neuroscience and Mental Health,
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22
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Alzheimer therapy with an antibody against N-terminal Abeta 4-X and pyroglutamate Abeta 3-X. Sci Rep 2015; 5:17338. [PMID: 26626428 PMCID: PMC4667289 DOI: 10.1038/srep17338] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/28/2015] [Indexed: 11/28/2022] Open
Abstract
Full-length Aβ1-42 and Aβ1-40, N-truncated pyroglutamate Aβ3-42 and Aβ4-42 are major variants in the Alzheimer brain. Aβ4-42 has not been considered as a therapeutic target yet. We demonstrate that the antibody NT4X and its Fab fragment reacting with both the free N-terminus of Aβ4-x and pyroglutamate Aβ3-X mitigated neuron loss in Tg4-42 mice expressing Aβ4-42 and completely rescued spatial reference memory deficits after passive immunization. NT4X and its Fab fragment also rescued working memory deficits in wild type mice induced by intraventricular injection of Aβ4-42. NT4X reduced pyroglutamate Aβ3-x, Aβx-40 and Thioflavin-S positive plaque load after passive immunization of 5XFAD mice. Aβ1-x and Aβx-42 plaque deposits were unchanged. Importantly, for the first time, we demonstrate that passive immunization using the antibody NT4X is therapeutically beneficial in Alzheimer mouse models showing that N-truncated Aβ starting with position four in addition to pyroglutamate Aβ3-x is a relevant target to fight Alzheimer’s disease.
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23
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Elnar AA, Allouche A, Desor F, Yen FT, Soulimani R, Oster T. Lactational exposure of mice to low levels of non-dioxin-like polychlorinated biphenyls increases susceptibility to neuronal stress at a mature age. Neurotoxicology 2015; 53:314-320. [PMID: 26480858 DOI: 10.1016/j.neuro.2015.10.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Accepted: 10/05/2015] [Indexed: 11/27/2022]
Abstract
Lactational exposure to low levels of the sum of the six indicator polychlorinated biphenyls (Σ6 NDL-PCBs, 10ng/kg/day) is known to lead to persistent anxious behavior in young and adult offspring mice at postnatal days 40 and 160, respectively. At more advanced life stages, we evaluated the effects on the mouse brain of neuronal stress induced by the synaptotoxic amyloid-beta (Aβ) peptide. Perinatal exposure of lactating mice to Σ6 NDL-PCBs did not affect short-term memory performances of their offspring male mice aged 14 months as compared to control PCB-naive mice. However, following intracerebroventricular injection of soluble Aβ oligomers, significant impairments in long-term memory were detected in the mice that had been lactationally treated with Σ6 NDL-PCBs. In addition, immunoblot analyses of the synaptosomal fraction of hippocampal tissues from treated mice revealed a lower expression of the synaptic proteins synaptophysin and PSD-95. Though preliminary, our findings suggest for the first time that early exposure to low levels of NDL-PCBs induce late neuronal vulnerability to amyloid stress. Additional experiments are needed to confirm whether early environmental influences are involved in the etiology of brain aging and cognitive decline.
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Affiliation(s)
- Arpiné Ardzivian Elnar
- Neurotoxicologie Alimentaire et Bioactivité, MRCA, BP 4102, 57040 Metz, France; Université de Lorraine, Unité de Recherche Animal et Fonctionnalités des Produits Animaux (UR AFPA), EA3998, INRA USC 0340, France.
| | - Ahmad Allouche
- Biodisponibilité et Fonctionnalités des Lipides Alimentaires, BFLA, ENSAIA, Avenue de la forêt de Haye, 54500 Vandœuvre-lès-Nancy, France; Université de Lorraine, Unité de Recherche Animal et Fonctionnalités des Produits Animaux (UR AFPA), EA3998, INRA USC 0340, France
| | - Frédéric Desor
- Neurotoxicologie Alimentaire et Bioactivité, MRCA, BP 4102, 57040 Metz, France; Université de Lorraine, Unité de Recherche Animal et Fonctionnalités des Produits Animaux (UR AFPA), EA3998, INRA USC 0340, France
| | - Frances T Yen
- Biodisponibilité et Fonctionnalités des Lipides Alimentaires, BFLA, ENSAIA, Avenue de la forêt de Haye, 54500 Vandœuvre-lès-Nancy, France; Université de Lorraine, Unité de Recherche Animal et Fonctionnalités des Produits Animaux (UR AFPA), EA3998, INRA USC 0340, France
| | - Rachid Soulimani
- Neurotoxicologie Alimentaire et Bioactivité, MRCA, BP 4102, 57040 Metz, France; Université de Lorraine, Unité de Recherche Animal et Fonctionnalités des Produits Animaux (UR AFPA), EA3998, INRA USC 0340, France
| | - Thierry Oster
- Biodisponibilité et Fonctionnalités des Lipides Alimentaires, BFLA, ENSAIA, Avenue de la forêt de Haye, 54500 Vandœuvre-lès-Nancy, France; Université de Lorraine, Unité de Recherche Animal et Fonctionnalités des Produits Animaux (UR AFPA), EA3998, INRA USC 0340, France
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24
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Acute amnestic encephalopathy in amyloid-β oligomer-injected mice is due to their widespread diffusion in vivo. Neurobiol Aging 2015; 36:2043-52. [PMID: 25862419 DOI: 10.1016/j.neurobiolaging.2015.03.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 02/17/2015] [Accepted: 03/08/2015] [Indexed: 12/13/2022]
Abstract
Amyloid-β (Aβ) oligomers are the suspected culprit as initiators of Alzheimer's disease (AD). However, their diffusion in the brain remains unknown. Here, we studied Aβ oligomers' dissemination and evaluated their in vivo toxicity. Wild-type mice were injected with 50 pmol of synthetic Aβ oligomers (of different size) in the hippocampus. Oligomers diffused largely in the brain as soon as 1 hour and up to 7 days after injection. A transient encephalopathy with memory impairment was induced by this unique injection. The immunoreactivity of the postsynaptic marker PSD95 was diffusely decreased. Similar results (both on memory and PSD95 immunoreactivity) were obtained with delipidated and high molecular weight oligomers (>50 kDa) but not with smaller assemblies. Tau hyperphosphorylation was observed in the oligomer-injected brains. Finally, fos immunostaining was increased in Aβ-derived diffusible ligands-injected mice, suggesting neuronal hyperactivity. Rapid and widespread diffusion of Aβ oligomers was demonstrated in vivo and associated with decreased synaptic markers and memory deficits which gives new insight to the pathogenicity of Aβ.
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25
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Pivtoraiko VN, Abrahamson EE, Leurgans SE, DeKosky ST, Mufson EJ, Ikonomovic MD. Cortical pyroglutamate amyloid-β levels and cognitive decline in Alzheimer's disease. Neurobiol Aging 2015; 36:12-9. [PMID: 25048160 PMCID: PMC4268150 DOI: 10.1016/j.neurobiolaging.2014.06.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 06/12/2014] [Accepted: 06/19/2014] [Indexed: 02/02/2023]
Abstract
Posterior cingulate cortex (PCC) accumulates amyloid-β (Aβ) early in Alzheimer's disease (AD). The relative concentrations of full-length Aβ and truncated, pyroglutamate-modified Aβ (NpE3) forms, and their correlations to cognitive dysfunction in AD, are unknown. We quantified AβNpE3-42, AβNpE3-40, Aβ1-42, and Aβ1-40 concentrations in soluble (nonfibrillar) and insoluble (fibrillar) pools in PCC from subjects with an antemortem clinical diagnosis of no cognitive impairment, mild cognitive impairment, or mild-moderate AD. In clinical AD, increased PCC concentrations of Aβ were observed for all Aβ forms in the insoluble pool but only for Aβ1-42 in the soluble pool. Lower Mini-Mental State Exam and episodic memory scores correlated most strongly with higher concentrations of soluble and insoluble Aβ1-42. Greater neuropathology severity by Consortium to Establish a Registry for Alzheimer's Disease and National Institute on Aging-Reagan pathologic criteria was associated with higher concentrations of all measured Aβ forms, except soluble AβNpE3-40. Low concentrations of soluble pyroglutamate Aβ across clinical groups likely reflect its rapid sequestration into plaques, thus, the conversion to fibrillar Aβ may be a therapeutic target.
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Affiliation(s)
| | - Eric E Abrahamson
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, USA; Geriatric Research Education and Clinical Center, VA Pittsburgh Healthcare System, Pittsburgh, PA, USA
| | - Sue E Leurgans
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL
| | - Steven T DeKosky
- Department of Neurology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Elliott J Mufson
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Milos D Ikonomovic
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, USA; Geriatric Research Education and Clinical Center, VA Pittsburgh Healthcare System, Pittsburgh, PA, USA; Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA.
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26
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Kummer MP, Heneka MT. Truncated and modified amyloid-beta species. ALZHEIMERS RESEARCH & THERAPY 2014; 6:28. [PMID: 25031638 PMCID: PMC4055046 DOI: 10.1186/alzrt258] [Citation(s) in RCA: 214] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Alzheimer’s disease pathology is closely connected to the processing of the amyloid precursor protein (APP) resulting in the formation of a variety of amyloid-beta (Aβ) peptides. They are found as insoluble aggregates in senile plaques, the histopathological hallmark of the disease. These peptides are also found in soluble, mostly monomeric and dimeric, forms in the interstitial and cerebrospinal fluid. Due to the combination of several enzymatic activities during APP processing, Aβ peptides exist in multiple isoforms possessing different N-termini and C-termini. These peptides include, to a certain extent, part of the juxtamembrane and transmembrane domain of APP. Besides differences in size, post-translational modifications of Aβ – including oxidation, phosphorylation, nitration, racemization, isomerization, pyroglutamylation, and glycosylation – generate a plethora of peptides with different physiological and pathological properties that may modulate disease progression.
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Affiliation(s)
- Markus P Kummer
- Department of Neurology, University Hospital Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany
| | - Michael T Heneka
- Department of Neurology, University Hospital Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany ; German Center for Neurodegenerative Diseases (DZNE), Holbeinstrasse 15, 53117 Bonn, Germany
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27
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Kroker KS, Mathis C, Marti A, Cassel JC, Rosenbrock H, Dorner-Ciossek C. PDE9A inhibition rescues amyloid beta-induced deficits in synaptic plasticity and cognition. Neurobiol Aging 2014; 35:2072-8. [PMID: 24746365 DOI: 10.1016/j.neurobiolaging.2014.03.023] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 03/14/2014] [Accepted: 03/20/2014] [Indexed: 02/02/2023]
Abstract
The cyclic nucleotide cGMP is an important intracellular messenger for synaptic plasticity and memory function in rodents. Therefore, inhibition of cGMP degrading phosphodiesterases, like PDE9A, has gained interest as potential target for treatment of cognition deficits in indications like Alzheimer's disease (AD). In fact, PDE9A inhibition results in increased hippocampal long-term potentiation and exhibits procognitive effects in rodents. To date, however, no evidence has been published linking PDE9A inhibition to the pathologic hallmarks of AD such as amyloid beta (Aβ) deposition. Therefore, we investigated the role of PDE9A inhibition in an AD relevant context by testing its effects on Aβ-related deficits in synaptic plasticity and cognition. The PDE9A inhibitor BAY 73-6691 was found to restore long-term potentiation impaired by Aβ42 oligomers. Furthermore, we demonstrated that BAY 73-6691 enhanced cGMP levels in the hippocampus of APP transgenic tg2576 mice and improved memory performance of these mice. Altogether, our results support the hypothesis that inhibition of PDE9A could be a beneficial approach for the treatment of memory impairment in AD patients.
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Affiliation(s)
- Katja S Kroker
- Department of CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany.
| | - Chantal Mathis
- Laboratoire de Neurosciences Cognitives et Adaptatives, CNRS, Université de Strasbourg UMR 7364, GDR CNRS 2905, Strasbourg, France
| | - Anelise Marti
- Department of CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany
| | - Jean-Christophe Cassel
- Laboratoire de Neurosciences Cognitives et Adaptatives, CNRS, Université de Strasbourg UMR 7364, GDR CNRS 2905, Strasbourg, France
| | - Holger Rosenbrock
- Department of CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany
| | - Cornelia Dorner-Ciossek
- Department of CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany
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28
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Amyloid beta-derived diffusible ligands (ADDLs) induce abnormal expression of insulin receptors in rat hippocampal neurons. J Mol Neurosci 2014; 52:124-30. [PMID: 24402880 DOI: 10.1007/s12031-013-0216-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Accepted: 12/18/2013] [Indexed: 01/12/2023]
Abstract
Amyloid beta (Aβ) is an important pathogenic factor in Alzheimer's disease (AD). In this study, we investigated the hypothesis that administration of amyloid-derived diffusible ligands (ADDLs) prepared from a synthetic Aβ(1-42) amyloid peptide can cause defective expression of insulin receptors (IRs). To this end, primary rat hippocampal neurons were treated with various concentrations of ADDLs and expression levels of IRs were measured using real-time PCR and western blots. In these experiments, the expression of IRs significantly increased following treatment with low concentrations of Aβ(1-42). In contrast, when higher concentrations of Aβ(1-42) were applied, the number of apoptotic cells present increased, and expression of IRs significantly decreased. In combination, these results suggest that ADDLs is able to induce abnormal expression of IRs and interrupt normal insulin signaling, thereby potentially contributing to central insulin resistance that can occur during progression of AD.
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29
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Perez-Garmendia R, Gevorkian G. Pyroglutamate-Modified Amyloid Beta Peptides: Emerging Targets for Alzheimer´s Disease Immunotherapy. Curr Neuropharmacol 2014; 11:491-8. [PMID: 24403873 PMCID: PMC3763757 DOI: 10.2174/1570159x11311050004] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 03/16/2013] [Accepted: 03/28/2013] [Indexed: 12/25/2022] Open
Abstract
Extracellular and intraneuronal accumulation of amyloid-beta (Aβ) peptide aggregates in the brain has been hypothesized to play an important role in the neuropathology of Alzheimer’s Disease (AD). The main Aβ variants detected in the human brain are Aβ1-40 and Aβ1-42, however a significant proportion of AD brain Aβ consists also of N-terminal truncated species. Pyroglutamate-modified Aβ peptides have been demonstrated to be the predominant components among all N-terminal truncated Aβ species in AD brains and represent highly desirable and abundant therapeutic targets. The current review describes the properties and localization of two pyroglutamate-modified Aβ peptides, AβN3(pE) and AβN11(pE), in the brain. The role of glutaminyl cyclase (QC) in the formation of these peptides is also addressed. In addition, two potential therapeutic strategies, the inhibition of QC and immunotherapy approaches, and clinical trials aimed to target these important pathological Aβ species are reviewed.
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Affiliation(s)
- Roxanna Perez-Garmendia
- Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico (UNAM), Mexico DF, Mexico
| | - Goar Gevorkian
- Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico (UNAM), Mexico DF, Mexico
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30
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N-truncated Abeta starting with position four: early intraneuronal accumulation and rescue of toxicity using NT4X-167, a novel monoclonal antibody. Acta Neuropathol Commun 2013; 1:56. [PMID: 24252153 PMCID: PMC3893517 DOI: 10.1186/2051-5960-1-56] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 08/10/2013] [Indexed: 12/27/2022] Open
Abstract
Background The amyloid hypothesis in Alzheimer disease (AD) considers amyloid β peptide (Aβ) deposition causative in triggering down-stream events like neurofibrillary tangles, cell loss, vascular damage and memory decline. In the past years N-truncated Aβ peptides especially N-truncated pyroglutamate AβpE3-42 have been extensively studied. Together with full-length Aβ1–42 and Aβ1–40, N-truncated AβpE3-42 and Aβ4–42 are major variants in AD brain. Although Aβ4–42 has been known for a much longer time, there is a lack of studies addressing the question whether AβpE3-42 or Aβ4–42 may precede the other in Alzheimer’s disease pathology. Results Using different Aβ antibodies specific for the different N-termini of N-truncated Aβ, we discovered that Aβ4-x preceded AβpE3-x intraneuronal accumulation in a transgenic mouse model for AD prior to plaque formation. The novel Aβ4-x immunoreactive antibody NT4X-167 detected high molecular weight aggregates derived from N-truncated Aβ species. While NT4X-167 significantly rescued Aβ4–42 toxicity in vitro no beneficial effect was observed against Aβ1–42 or AβpE3-42 toxicity. Phenylalanine at position four of Aβ was imperative for antibody binding, because its replacement with alanine or proline completely prevented binding. Although amyloid plaques were observed using NT4X-167 in 5XFAD transgenic mice, it barely reacted with plaques in the brain of sporadic AD patients and familial cases with the Arctic, Swedish and the presenilin-1 PS1Δ9 mutation. A consistent staining was observed in blood vessels in all AD cases with cerebral amyloid angiopathy. There was no cross-reactivity with other aggregates typical for other common neurodegenerative diseases showing that NT4X-167 staining is specific for AD. Conclusions Aβ4-x precedes AβpE3-x in the well accepted 5XFAD AD mouse model underlining the significance of N-truncated species in AD pathology. NT4X-167 therefore is the first antibody reacting with Aβ4-x and represents a novel tool in Alzheimer research.
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31
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Bouter Y, Dietrich K, Wittnam JL, Rezaei-Ghaleh N, Pillot T, Papot-Couturier S, Lefebvre T, Sprenger F, Wirths O, Zweckstetter M, Bayer TA. N-truncated amyloid β (Aβ) 4-42 forms stable aggregates and induces acute and long-lasting behavioral deficits. Acta Neuropathol 2013; 126:189-205. [PMID: 23685882 PMCID: PMC3722453 DOI: 10.1007/s00401-013-1129-2] [Citation(s) in RCA: 134] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 05/08/2013] [Accepted: 05/09/2013] [Indexed: 12/30/2022]
Abstract
N-truncated Aβ4-42 is highly abundant in Alzheimer disease (AD) brain and was the first Aβ peptide discovered in AD plaques. However, a possible role in AD aetiology has largely been neglected. In the present report, we demonstrate that Aβ4-42 rapidly forms aggregates possessing a high aggregation propensity in terms of monomer consumption and oligomer formation. Short-term treatment of primary cortical neurons indicated that Aβ4-42 is as toxic as pyroglutamate Aβ3-42 and Aβ1-42. In line with these findings, treatment of wildtype mice using intraventricular Aβ injection induced significant working memory deficits with Aβ4-42, pyroglutamate Aβ3-42 and Aβ1-42. Transgenic mice expressing Aβ4-42 (Tg4-42 transgenic line) developed a massive CA1 pyramidal neuron loss in the hippocampus. The hippocampus-specific expression of Aβ4-42 correlates well with age-dependent spatial reference memory deficits assessed by the Morris water maze test. Our findings indicate that N-truncated Aβ4-42 triggers acute and long-lasting behavioral deficits comparable to AD typical memory dysfunction.
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Affiliation(s)
- Yvonne Bouter
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
| | - Katharina Dietrich
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
| | - Jessica L. Wittnam
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
| | - Nasrollah Rezaei-Ghaleh
- Department for NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Germany
| | | | | | | | - Frederick Sprenger
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
| | - Oliver Wirths
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), 37077 Göttingen, Germany
- Department for NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Germany
| | - Thomas A. Bayer
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
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32
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Kroker KS, Moreth J, Kussmaul L, Rast G, Rosenbrock H. Restoring long-term potentiation impaired by amyloid-beta oligomers: Comparison of an acetylcholinesterase inhibitior and selective neuronal nicotinic receptor agonists. Brain Res Bull 2013; 96:28-38. [DOI: 10.1016/j.brainresbull.2013.04.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 04/12/2013] [Accepted: 04/15/2013] [Indexed: 12/25/2022]
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33
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Meral D, Urbanc B. Discrete molecular dynamics study of oligomer formation by N-terminally truncated amyloid β-protein. J Mol Biol 2013; 425:2260-75. [PMID: 23500806 PMCID: PMC3665754 DOI: 10.1016/j.jmb.2013.03.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Accepted: 03/05/2013] [Indexed: 01/09/2023]
Abstract
In Alzheimer's disease (AD), amyloid β-protein (Aβ) self-assembles into toxic oligomers. Of the two predominant Aβ alloforms, Aβ1-40 and Aβ1-42, the latter is particularly strongly linked to AD. N-terminally truncated and pyroglutamated Aβ peptides were recently shown to seed Aβ aggregation and contribute significantly to Aβ-mediated toxicity, yet their folding and assembly were not explored computationally. Discrete molecular dynamics approach previously captured in vitro-derived distinct Aβ1-40 and Aβ1-42 oligomer size distributions and predicted that the more toxic Aβ1-42 oligomers had more flexible and solvent-exposed N-termini than Aβ1-40 oligomers. Here, we examined oligomer formation of Aβ3-40, Aβ3-42, Aβ11-40, and Aβ11-42 by the discrete molecular dynamics approach. The four N-terminally truncated peptides showed increased oligomerization propensity relative to the full-length peptides, consistent with in vitro findings. Conformations formed by Aβ3-40/42 had significantly more flexible and solvent-exposed N-termini than Aβ1-40/42 conformations. In contrast, in Aβ11-40/42 conformations, the N-termini formed more contacts and were less accessible to the solvent. The compactness of the Aβ11-40/42 conformations was in part facilitated by Val12. Two single amino acid substitutions that reduced and abolished hydrophobicity at position 12, respectively, resulted in a proportionally increased structural variability. Our results suggest that Aβ11-40 and Aβ11-42 oligomers might be less toxic than Aβ1-40 and Aβ1-42 oligomers and offer a plausible explanation for the experimentally observed increased toxicity of Aβ3-40 and Aβ3-42 and their pyroglutamated forms.
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Affiliation(s)
- Derya Meral
- Department of Physics, Drexel University, Philadelphia, PA 19104, USA
| | - Brigita Urbanc
- Department of Physics, Drexel University, Philadelphia, PA 19104, USA
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34
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De Kimpe L, van Haastert ES, Kaminari A, Zwart R, Rutjes H, Hoozemans JJM, Scheper W. Intracellular accumulation of aggregated pyroglutamate amyloid beta: convergence of aging and Aβ pathology at the lysosome. AGE (DORDRECHT, NETHERLANDS) 2013; 35:673-687. [PMID: 22477259 PMCID: PMC3636379 DOI: 10.1007/s11357-012-9403-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 03/09/2012] [Indexed: 05/27/2023]
Abstract
Deposition of aggregated amyloid beta (Aβ) is a major hallmark of Alzheimer's disease (AD)-a common age-related neurodegenerative disorder. Typically, Aβ is generated as a peptide of varying lengths. However, a major fraction of Aβ peptides in the brains of AD patients has undergone posttranslational modifications, which often radically change the properties of the peptides. Aβ3(pE)-42 is an N-truncated, pyroglutamate-modified variant that is abundantly present in AD brain and was suggested to play a role early in the pathogenesis. Here we show that intracellular accumulation of oligomeric aggregates of Aβ3(pE)-42 results in loss of lysosomal integrity. Using a novel antibody specific for aggregates of AβpE3, we show that in postmortem human brain tissue, aggregated AβpE3 is predominantly found in the lysosomes of both neurons and glial cells. Our data further demonstrate that AβpE3 is relatively resistant to lysosomal degradation, which may explain its accumulation in the lysosomes. The intracellular AβpE3 aggregates increase in an age-dependent manner. The results presented in this study support a model where Aβ pathology and aging converge, leading to accumulation of the degradation-resistant pE-modified Aβ in the lysosomes, lysosomal dysfunction, and neurodegeneration.
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Affiliation(s)
- Line De Kimpe
- Department of Genome Analysis, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Elise S. van Haastert
- Department of Pathology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Archontia Kaminari
- Department of Genome Analysis, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Rob Zwart
- Department of Genome Analysis, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Helma Rutjes
- Hycult Biotech, Frontstraat 2a, 5405 PB Uden, The Netherlands
| | - Jeroen J. M. Hoozemans
- Department of Pathology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Wiep Scheper
- Department of Genome Analysis, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
- Department of Neurology, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
- Department of Genome Analysis, Academic Medical Center, P.O. Box 22660, 1100 DE Amsterdam, The Netherlands
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Gabelle A, Richard F, Gutierrez LA, Schraen S, Delva F, Rouaud O, Buée L, Dartigues JF, Touchon J, Lambert JC, Berr C. Plasma amyloid-β levels and prognosis in incident dementia cases of the 3-City Study. J Alzheimers Dis 2013; 33:381-91. [PMID: 22976074 DOI: 10.3233/jad-2012-121147] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Studies of plasma amyloid-β (Aβ) levels as potential biomarkers for incident Alzheimer's disease (AD) have yielded contradictory results. We explored the associations between plasma Aβ(40), Aβ(42), and truncated Aβ levels, and prognosis of dementia in participants of the prospective 3-City Study. 120 aged individuals diagnosed with 2-year incident dementia were followed up for seven years. The associations between Aβ plasma levels and baseline cognitive score, cognitive decline, and death were examined. A higher level of baseline plasma Aβ was associated with worse cognitive status two years prior to incident dementia diagnosis. In incident AD patients, the association was only significant for Aβ(40) and Aβ(n-42). In the fast cognitive decliners group, especially in AD cases, a higher level of 5 pg/ml of baseline Aβ(42), Aβ(n-42), Aβ(n-42)/Aβ(n-40), and Aβ(42)/Aβ(40) ratios were associated with a lower risk of fast cognitive decline based on the Isaacs Set Test score. There was no association between peptide levels and mortality in demented subjects. When assayed at prodromal stage, plasma Aβ levels may be potentially useful markers of fast cognitive decline in individuals who subsequently become demented.
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Affiliation(s)
- Audrey Gabelle
- Department of Neurology, Centre Mémoire Ressources Recherche Languedoc-Roussillon, CHRU Gui de Chauliac Hospital, Montpellier, France.
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36
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Alzheimer's disease Aβ assemblies mediating rapid disruption of synaptic plasticity and memory. Mol Brain 2012; 5:25. [PMID: 22805374 PMCID: PMC3502131 DOI: 10.1186/1756-6606-5-25] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 06/22/2012] [Indexed: 01/24/2023] Open
Abstract
Alzheimer’s disease (AD) is characterized by episodic memory impairment that often precedes clinical diagnosis by many years. Probing the mechanisms of such impairment may provide much needed means of diagnosis and therapeutic intervention at an early, pre-dementia, stage. Prior to the onset of significant neurodegeneration, the structural and functional integrity of synapses in mnemonic circuitry is severely compromised in the presence of amyloidosis. This review examines recent evidence evaluating the role of amyloid-ß protein (Aβ) in causing rapid disruption of synaptic plasticity and memory impairment. We evaluate the relative importance of different sizes and conformations of Aβ, including monomer, oligomer, protofibril and fibril. We pay particular attention to recent controversies over the relevance to the pathophysiology of AD of different water soluble Aβ aggregates and the importance of cellular prion protein in mediating their effects. Current data are consistent with the view that both low-n oligomers and larger soluble assemblies present in AD brain, some of them via a direct interaction with cellular prion protein, cause synaptic memory failure. At the two extremes of aggregation, monomers and fibrils appear to act in vivo both as sources and sinks of certain metastable conformations of soluble aggregates that powerfully disrupt synaptic plasticity. The same principle appears to apply to other synaptotoxic amyloidogenic proteins including tau, α-synuclein and prion protein.
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37
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Han X, Ma Y, Liu X, Wang L, Qi S, Zhang Q, Du Y. Changes in insulin-signaling transduction pathway underlie learning/memory deficits in an Alzheimer’s disease rat model. J Neural Transm (Vienna) 2012; 119:1407-16. [DOI: 10.1007/s00702-012-0803-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 03/29/2012] [Indexed: 12/20/2022]
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38
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Kumar V, Gupta MK, Singh G, Prabhakar YS. CP-MLR/PLS directed QSAR study on the glutaminyl cyclase inhibitory activity of imidazoles: rationales to advance the understanding of activity profile. J Enzyme Inhib Med Chem 2012; 28:515-22. [DOI: 10.3109/14756366.2011.654111] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Viney Kumar
- Molecular Modelling and Pharmacoinformatics Lab, Department of Pharmaceutical Chemistry, ISF College of Pharmacy,
Moga, India
| | - Manish K. Gupta
- Molecular Modelling and Pharmacoinformatics Lab, Department of Pharmaceutical Chemistry, ISF College of Pharmacy,
Moga, India
| | - Gagandip Singh
- Molecular Modelling and Pharmacoinformatics Lab, Department of Pharmaceutical Chemistry, ISF College of Pharmacy,
Moga, India
| | - Yenamandra S. Prabhakar
- Medicinal and Process Chemistry Division, Central Drug Research Institute,
CSIR, Lucknow, India
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39
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Desbène C, Malaplate-Armand C, Youssef I, Garcia P, Stenger C, Sauvée M, Fischer N, Rimet D, Koziel V, Escanyé MC, Oster T, Kriem B, Yen FT, Pillot T, Olivier JL. Critical role of cPLA2 in Aβ oligomer-induced neurodegeneration and memory deficit. Neurobiol Aging 2011; 33:1123.e17-29. [PMID: 22188721 DOI: 10.1016/j.neurobiolaging.2011.11.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 11/03/2011] [Accepted: 11/04/2011] [Indexed: 12/23/2022]
Abstract
Soluble beta-amyloid (Aβ) oligomers are considered to putatively play a critical role in the early synapse loss and cognitive impairment observed in Alzheimer's disease. We previously demonstrated that Aβ oligomers activate cytosolic phospholipase A(2) (cPLA(2)), which specifically releases arachidonic acid from membrane phospholipids. We here observed that cPLA(2) gene inactivation prevented the alterations of cognitive abilities and the reduction of hippocampal synaptic markers levels noticed upon a single intracerebroventricular injection of Aβ oligomers in wild type mice. We further demonstrated that the Aβ oligomer-induced sphingomyelinase activation was suppressed and that phosphorylation of Akt/protein kinase B (PKB) was preserved in neuronal cells isolated from cPLA(2)(-/-) mice. Interestingly, expression of the Aβ precursor protein (APP) was reduced in hippocampus homogenates and neuronal cells from cPLA(2)(-/-) mice, but the relationship with the resistance of these mice to the Aβ oligomer toxicity requires further investigation. These results therefore show that cPLA(2) plays a key role in the Aβ oligomer-associated neurodegeneration, and as such represents a potential therapeutic target for the treatment of Alzheimer's disease.
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Affiliation(s)
- Cédric Desbène
- Lipidomix (EA 4422), INPL-ENSAIA, Université de Lorraine, Vandœuvre-lès-Nancy, France
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40
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Drew SC, Barnham KJ. The heterogeneous nature of Cu2+ interactions with Alzheimer's amyloid-β peptide. Acc Chem Res 2011; 44:1146-55. [PMID: 21714485 DOI: 10.1021/ar200014u] [Citation(s) in RCA: 144] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive cognitive and memory impairment. Within the brain, senile plaques, which comprise extracellular deposits of the amyloid-β peptide (Aβ), are the most common pathological feature of AD. A high concentration of Cu(2+) is found within these plaques, which are also areas under oxidative stress. Laboratory work has shown that in vitro Aβ will react with Cu(2+) to induce peptide aggregation and the production of reactive oxygen species. As such, this interaction offers a possible explanation for two of the defining pathological features observed in the AD brain: the presence of amyloid plaques, which consist largely of insoluble Aβ aggregates, and the abundant oxidative stress therein. Researchers have accordingly put forth the "metals hypothesis" of AD, which postulates that compounds designed to inhibit Cu(2+)/Aβ interactions and redistribute Cu(2+) may offer therapeutic potential for treating AD. Characterization of the pH-dependent Cu(2+) coordination of Aβ is fundamental to understanding the neurological relevance of Cu(2+)/Aβ interactions and aiding the design of new therapeutic agents. In an effort to shed light on the problem, many experimental and theoretical techniques, using a variety of model systems, have been undertaken. The preceding decade has seen numerous conflicting spectroscopic reports concerning the nature of the Cu(2+)/Aβ coordination. As the number of studies has grown, the nature of the pH-dependent ligand environment surrounding the Cu(2+) cation has remained a point of contention. In large part, the difficulties can be attributed to inappropriate choices of the model system or to methods that are incapable of quantitatively delineating the presence and identity of multiple Cu(2+) coordination modes. Electron paramagnetic resonance (EPR) is the method of choice for studying paramagnetic metal-protein interactions. With the introduction of site-specific (15)N, (17)O, and (13)C isotopic labels and the application of advanced techniques, EPR is capable of eliminating much of the ambiguity. Recent EPR studies have produced the most definitive picture of the pH-dependent Cu(2+) coordination modes of Aβ and enabled researchers to address the inconsistencies present in the literature. In this Account, we begin by briefly introducing the evidence for a role of Cu(2+) in AD as well as the potential physiological and therapeutic implications of that role. We then outline the EPR methodology used to resolve the molecular details of the Cu(2+)/Aβ interactions. No drugs are currently available for altering the course of AD, and existing therapies only offer short-term symptomatic relief. This focused picture of the role of Cu(2+) in AD-related plaques offers welcome potential for the development of new methods to combat this devastating disease.
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Affiliation(s)
- Simon C. Drew
- Max Planck Institute for Bioinorganic Chemistry, 45470 Mülheim an der Ruhr, Germany
| | - Kevin J. Barnham
- Department of Pathology, The Bio21 Molecular Science and Biotechnology Institute, and the Mental Health Research Institute, The University of Melbourne, Victoria 3010, Australia
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41
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A peptide that binds specifically to the β-amyloid of Alzheimer's disease: selection and assessment of anti-β-amyloid neurotoxic effects. PLoS One 2011; 6:e27649. [PMID: 22102917 PMCID: PMC3213187 DOI: 10.1371/journal.pone.0027649] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 10/21/2011] [Indexed: 11/24/2022] Open
Abstract
The accumulation of the amyloid-β peptide (Aβ) into amyloid plaques, an essential event in Alzheimer's disease (AD) pathogenesis, has caused researchers to seek compounds that physiologically bind Aβ and modulate its aggregation and neurotoxicity. In order to develop new Aβ-specific peptides for AD, a randomized 12-mer peptide library with Aβ1-10 as the target was used to identify peptides in the present study. After three rounds of selection, specific phages were screened, and their binding affinities to Aβ1-10 were found to be highly specific. Finally, a special peptide was synthesized according to the sequences of the selected phages. In addition, the effects of the special peptide on Aβ aggregation and Aβ-mediated neurotoxicity in vitro and in vivo were assessed. The results show that the special peptide not only inhibited the aggregation of Aβ into plaques, but it also alleviated Aβ-induced PC12 cell viability and apoptosis at appropriate concentrations as assessed by the cell counting kit-8 assay and propidium iodide staining. Moreover, the special peptide exhibited a protective effect against Aβ-induced learning and memory deficits in rats, as determined by the Morris water maze task. In conclusion, we selected a peptide that specifically binds Aβ1-10 and can modulate Aβ aggregation and Aβ-induced neuronal damage. This opens up possibilities for the development of a novel therapeutic approach for the treatment of AD.
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Abstract
The treatment of moderate to severe Alzheimer's disease is reviewed with regard to mechanisms of action, pharmacokinetics, metabolism, safety/tolerability, and efficacy in reducing cognitive, behavioral/psychiatric, functional and global symptoms. The cholinesterase inhibitors donepezil, rivastigmine and galantamine and the N-methyl-d-aspartate receptor channel blocker memantine are moderately beneficial. Small improvements over a few months are followed by slowed mental decline. Concerning cognitive, functional and global functions, these drugs are similarly effective. Cholinesterase inhibitors also reduce apathy, memantine counteracts agitation and aggression. Serious adverse effects are rare with all four drugs. Cholinesterase inhibitors bear a risk for patients with cardiac diseases. Adverse emetic events are typical for oral formulations of these drugs, but less for rivastigmine transdermal patches. Other routes of administration and use of a galantamine prodrug are currently investigated. The superiority of combination therapies over monotherapies requires further support. Promising investigational drugs include the copper/zinc ionophore PBT2 and multifunctional hybrid molecules.
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Affiliation(s)
- Rüdiger Hardeland
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, University of Göttingen, Berliner Str. 28, D-37073 Göttingen, Germany
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43
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Jawhar S, Wirths O, Bayer TA. Pyroglutamate amyloid-β (Aβ): a hatchet man in Alzheimer disease. J Biol Chem 2011; 286:38825-32. [PMID: 21965666 DOI: 10.1074/jbc.r111.288308] [Citation(s) in RCA: 165] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Pyroglutamate-modified amyloid-β (Aβ(pE3)) peptides are gaining considerable attention as potential key participants in the pathology of Alzheimer disease (AD) due to their abundance in AD brain, high aggregation propensity, stability, and cellular toxicity. Transgenic mice that produce high levels of Aβ(pE3-42) show severe neuron loss. Recent in vitro and in vivo experiments have proven that the enzyme glutaminyl cyclase catalyzes the formation of Aβ(pE3). In this minireview, we summarize the current knowledge on Aβ(pE3), discussing its discovery, biochemical properties, molecular events determining formation, prevalence in the brains of AD patients, Alzheimer mouse models, and potential as a target for therapy and as a diagnostic marker.
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Affiliation(s)
- Sadim Jawhar
- Department of Molecular Psychiatry, Georg-August-University Göttingen, University Medicine Göttingen, 37075 Göttingen, Germany
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44
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Drew SC, Masters CL, Barnham KJ. Alzheimer's Aβ peptides with disease-associated N-terminal modifications: influence of isomerisation, truncation and mutation on Cu2+ coordination. PLoS One 2010; 5:e15875. [PMID: 21209855 PMCID: PMC3012727 DOI: 10.1371/journal.pone.0015875] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Accepted: 11/29/2010] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND The amyloid-β (Aβ) peptide is the primary component of the extracellular senile plaques characteristic of Alzheimer's disease (AD). The metals hypothesis implicates redox-active copper ions in the pathogenesis of AD and the Cu(2+) coordination of various Aβ peptides has been widely studied. A number of disease-associated modifications involving the first 3 residues are known, including isomerisation, mutation, truncation and cyclisation, but are yet to be characterised in detail. In particular, Aβ in plaques contain a significant amount of truncated pyroglutamate species, which appear to correlate with disease progression. METHODOLOGY/PRINCIPAL FINDINGS We previously characterised three Cu(2+)/Aβ1-16 coordination modes in the physiological pH range that involve the first two residues. Based upon our finding that the carbonyl of Ala2 is a Cu(2+) ligand, here we speculate on a hypothetical Cu(2+)-mediated intramolecular cleavage mechanism as a source of truncations beginning at residue 3. Using EPR spectroscopy and site-specific isotopic labelling, we have also examined four Aβ peptides with biologically relevant N-terminal modifications, Aβ1[isoAsp]-16, Aβ1-16(A2V), Aβ3-16 and Aβ3[pE]-16. The recessive A2V mutation preserved the first coordination sphere of Cu(2+)/Aβ, but altered the outer coordination sphere. Isomerisation of Asp1 produced a single dominant species involving a stable 5-membered Cu(2+) chelate at the amino terminus. The Aβ3-16 and Aβ3[pE]-16 peptides both exhibited an equilibrium between two Cu(2+) coordination modes between pH 6-9 with nominally the same first coordination sphere, but with a dramatically different pH dependence arising from differences in H-bonding interactions at the N-terminus. CONCLUSIONS/SIGNIFICANCE N-terminal modifications significantly influence the Cu(2+) coordination of Aβ, which may be critical for alterations in aggregation propensity, redox-activity, resistance to degradation and the generation of the Aβ3-× (× = 40/42) precursor of disease-associated Aβ3[pE]-x species.
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Affiliation(s)
- Simon C Drew
- Department of Pathology, The University of Melbourne, Melbourne, Victoria, Australia.
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45
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Anti-11[E]-pyroglutamate-modified amyloid β antibodies cross-react with other pathological Aβ species: relevance for immunotherapy. J Neuroimmunol 2010; 229:248-55. [PMID: 20864186 DOI: 10.1016/j.jneuroim.2010.08.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 08/24/2010] [Accepted: 08/26/2010] [Indexed: 12/15/2022]
Abstract
N-truncated/modified forms of amyloid beta (Aß) peptide are found in diffused and dense core plaques in Alzheimer's disease (AD) and Down's syndrome patients as well as animal models of AD, and represent highly desirable therapeutic targets. In the present study we have focused on N-truncated/modified Aβ peptide bearing amino-terminal pyroglutamate at position 11 (AβN11(pE)). We identified two B-cell epitopes recognized by rabbit anti-AβN11(pE) polyclonal antibodies. Interestingly, rabbit anti-AβN11(pE) polyclonal antibodies bound also to full-length Aβ1-42 and N-truncated/modified AβN3(pE), suggesting that the three peptides may share a common B-cell epitope. Importantly, rabbit anti-AβN11(pE) antibodies bound to naturally occurring Aβ aggregates present in brain samples from AD patients. These results are potentially important for developing novel immunogens for targeting N-truncated/modified Aβ aggregates as well, since the most commonly used immunogens in the majority of vaccine studies have been shown to induce antibodies that recognize the N-terminal immunodominant epitope (EFRH) of the full length Aβ, which is absent in N-amino truncated peptides.
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46
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Gunn AP, Masters CL, Cherny RA. Pyroglutamate-Aβ: role in the natural history of Alzheimer's disease. Int J Biochem Cell Biol 2010; 42:1915-8. [PMID: 20833262 DOI: 10.1016/j.biocel.2010.08.015] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Revised: 08/26/2010] [Accepted: 08/26/2010] [Indexed: 01/22/2023]
Abstract
The accumulation of amyloid-beta (Aβ) peptides is believed to be a central contributor to the neurodegeneration typically seen in Alzheimer's disease (AD) brain. Aβ extracted from AD brains invariably possesses extensive truncations, yielding peptides of differing N- and C-terminal composition. Whilst Aβ is often abundant in the brains of cognitively normal elderly people, the brains of AD patients are highly enriched for N-terminally truncated Aβ bearing the pyroglutamate modification. Pyroglutamate-Aβ (pE-Aβ) has a higher propensity for oligomerisation and aggregation than full-length Aβ, potentially seeding the accumulation of neurotoxic Aβ oligomers and amyloid deposits. In addition, pE-Aβ has increased resistance to clearance by peptidases, causing these peptides to persist in biological fluids and tissues. The extensive deposition of pE-Aβ in human AD brain is under-represented in many transgenic mouse models of AD, reflecting major differences in the production and processing of Aβ peptides in these models compared to the human disease state.
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Affiliation(s)
- Adam P Gunn
- The Mental Health Research Institute, Parkville, VIC, Australia
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47
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Abstract
At present it is estimated that 25% of the population older than 85 years have significant cognitive impairment. The global prevalence of cognitive impairment and dementia including Alzheimer's disease is expected to rise significantly in proportion to increased life expectancy. Deterioration of memory function and ultimately establishment of Alzheimer's disease (AD) severely debilitates the affected individual, uncompromisingly decreasing the quality of life of both affected patients and their care givers. Moreover, the cost of providing adequate care to patients with AD is a significant burden to both family and the health care providers. Therefore, various attempts have been made to identify means of either delaying the onset of cognitive impairment or improving memory function in patients affected by AD. Among a number of participants, importance of dietary fatty acids in particular omega-3 based fatty acids have gained significant momentum. This article aims to review published evidences for the role of omega-3 in memory function.
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Affiliation(s)
- Imose Itua
- Department of Health and Applied Social Sciences, Liverpool Hope University, Hope Park, Liverpool, UK,
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48
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Ciliary neurotrophic factor cell-based delivery prevents synaptic impairment and improves memory in mouse models of Alzheimer's disease. J Neurosci 2010; 30:7516-27. [PMID: 20519526 DOI: 10.1523/jneurosci.4182-09.2010] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The development of novel therapeutic strategies for Alzheimer's disease (AD) represents one of the biggest unmet medical needs today. Application of neurotrophic factors able to modulate neuronal survival and synaptic connectivity is a promising therapeutic approach for AD. We aimed to determine whether the loco-regional delivery of ciliary neurotrophic factor (CNTF) could prevent amyloid-beta (Abeta) oligomer-induced synaptic damages and associated cognitive impairments that typify AD. To ensure long-term administration of CNTF in the brain, we used recombinant cells secreting CNTF encapsulated in alginate polymers. The implantation of these bioreactors in the brain of Abeta oligomer-infused mice led to a continuous secretion of recombinant CNTF and was associated with the robust improvement of cognitive performances. Most importantly, CNTF led to full recovery of cognitive functions associated with the stabilization of synaptic protein levels in the Tg2576 AD mouse model. In vitro as well as in vivo, CNTF activated a Janus kinase/signal transducer and activator of transcription-mediated survival pathway that prevented synaptic and neuronal degeneration. These preclinical studies suggest that CNTF and/or CNTF receptor-associated pathways may have AD-modifying activity through protection against progressive Abeta-related memory deficits. Our data also encourage additional exploration of ex vivo gene transfer for the prevention and/or treatment of AD.
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49
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Buchholz M, Hamann A, Aust S, Brandt W, Böhme L, Hoffmann T, Schilling S, Demuth HU, Heiser U. Inhibitors for Human Glutaminyl Cyclase by Structure Based Design and Bioisosteric Replacement. J Med Chem 2009; 52:7069-80. [DOI: 10.1021/jm900969p] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | - Wolfgang Brandt
- Department of Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry, Weinberg 3, D-06120 Halle, Germany
| | | | | | | | - Hans-Ulrich Demuth
- Department of Medicinal Chemistry
- Department of Enzymology
- Department of Preclinical Pharmacology
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50
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Acero G, Manoutcharian K, Vasilevko V, Munguia ME, Govezensky T, Coronas G, Luz-Madrigal A, Cribbs DH, Gevorkian G. Immunodominant epitope and properties of pyroglutamate-modified Abeta-specific antibodies produced in rabbits. J Neuroimmunol 2009; 213:39-46. [PMID: 19545911 PMCID: PMC2725226 DOI: 10.1016/j.jneuroim.2009.06.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Revised: 05/29/2009] [Accepted: 06/02/2009] [Indexed: 02/06/2023]
Abstract
N-truncated and N-modified forms of amyloid beta (Abeta) peptide are found in diffused and dense core plaques in Alzheimer's disease (AD) and Down's syndrome patients as well as transgenic mouse models of AD. Although the pathological significance of these shortened forms Abeta is not completely understood, previous studies have demonstrated that these peptides are significantly more resistant to degradation, aggregate more rapidly in vitro and exhibit similar or, in some cases, increased toxicity in hippocampal neuronal cultures compared to the full length peptides. In the present study we further investigated the mechanisms of toxicity of one of the most abundant N-truncated/modified Abeta peptide bearing amino-terminal pyroglutamate at position 3 (AbetaN3(pE)). We demonstrated that AbetaN3(pE) oligomers induce phosphatidyl serine externalization and membrane damage in SH-SY5Y cells. Also, we produced AbetaN3(pE)-specific polyclonal antibodies in rabbit and identified an immunodominant epitope recognized by anti-AbetaN3(pE) antibodies. Our results are important for developing new immunotherapeutic compounds specifically targeting AbetaN3(pE) aggregates since the most commonly used immunogens in the majority of vaccines for AD have been shown to induce antibodies that recognize the N-terminal immunodominant epitope (EFRH) of the full length Abeta, which is absent in N-amino truncated peptides.
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Affiliation(s)
- G Acero
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), AP 70228, Cuidad Universitaria, México DF, 04510, Mexico
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