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Okkels N, Grothe MJ, Taylor JP, Hasselbalch SG, Fedorova TD, Knudsen K, van der Zee S, van Laar T, Bohnen NI, Borghammer P, Horsager J. Cholinergic changes in Lewy body disease: implications for presentation, progression and subtypes. Brain 2024; 147:2308-2324. [PMID: 38437860 DOI: 10.1093/brain/awae069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 02/05/2024] [Accepted: 02/13/2024] [Indexed: 03/06/2024] Open
Abstract
Cholinergic degeneration is significant in Lewy body disease, including Parkinson's disease, dementia with Lewy bodies, and isolated REM sleep behaviour disorder. Extensive research has demonstrated cholinergic alterations in the CNS of these disorders. More recently, studies have revealed cholinergic denervation in organs that receive parasympathetic denervation. This enables a comprehensive review of cholinergic changes in Lewy body disease, encompassing both central and peripheral regions, various disease stages and diagnostic categories. Across studies, brain regions affected in Lewy body dementia show equal or greater levels of cholinergic impairment compared to the brain regions affected in Lewy body disease without dementia. This observation suggests a continuum of cholinergic alterations between these disorders. Patients without dementia exhibit relative sparing of limbic regions, whereas occipital and superior temporal regions appear to be affected to a similar extent in patients with and without dementia. This implies that posterior cholinergic cell groups in the basal forebrain are affected in the early stages of Lewy body disorders, while more anterior regions are typically affected later in the disease progression. The topographical changes observed in patients affected by comorbid Alzheimer pathology may reflect a combination of changes seen in pure forms of Lewy body disease and those seen in Alzheimer's disease. This suggests that Alzheimer co-pathology is important to understand cholinergic degeneration in Lewy body disease. Thalamic cholinergic innervation is more affected in Lewy body patients with dementia compared to those without dementia, and this may contribute to the distinct clinical presentations observed in these groups. In patients with Alzheimer's disease, the thalamus is variably affected, suggesting a different sequential involvement of cholinergic cell groups in Alzheimer's disease compared to Lewy body disease. Patients with isolated REM sleep behaviour disorder demonstrate cholinergic denervation in abdominal organs that receive parasympathetic innervation from the dorsal motor nucleus of the vagus, similar to patients who experienced this sleep disorder in their prodrome. This implies that REM sleep behaviour disorder is important for understanding peripheral cholinergic changes in both prodromal and manifest phases of Lewy body disease. In conclusion, cholinergic changes in Lewy body disease carry implications for understanding phenotypes and the influence of Alzheimer co-pathology, delineating subtypes and pathological spreading routes, and for developing tailored treatments targeting the cholinergic system.
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Affiliation(s)
- Niels Okkels
- Department of Neurology, Aarhus University Hospital, 8200 Aarhus N, Denmark
- Department of Nuclear Medicine and PET, Aarhus University Hospital, 8200 Aarhus N, Denmark
| | - Michel J Grothe
- Unidad de Trastornos del Movimiento, Servicio de Neurología y Neurofisiología Clínica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Seville, Spain
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Reina Sofia Alzheimer's Centre, CIEN Foundation-ISCIII, 28031 Madrid, Spain
| | - John-Paul Taylor
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Steen Gregers Hasselbalch
- Danish Dementia Research Center, Department of Neurology, Copenhagen University Hospital, 2100 Copenhagen Ø, Denmark
- Department of Clinical Medicine, University of Copenhagen, 2100 Copenhagen Ø, Denmark
| | - Tatyana D Fedorova
- Department of Nuclear Medicine and PET, Aarhus University Hospital, 8200 Aarhus N, Denmark
| | - Karoline Knudsen
- Department of Nuclear Medicine and PET, Aarhus University Hospital, 8200 Aarhus N, Denmark
| | - Sygrid van der Zee
- Department of Neurology, University of Groningen, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Teus van Laar
- Department of Neurology, University of Groningen, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Nicolaas I Bohnen
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Radiology, University of Michigan, Ann Arbor, MI 48109, USA
- Neurology Service and GRECC, VA Ann Arbor Healthcare System, Ann Arbor, MI 48105, USA
- Morris K. Udall Center of Excellence for Parkinson's Disease Research, University of Michigan, Ann Arbor, MI 48109, USA
- Parkinson's Foundation Research Center of Excellence, University of Michigan, Ann Arbor, MI 48109, USA
| | - Per Borghammer
- Department of Nuclear Medicine and PET, Aarhus University Hospital, 8200 Aarhus N, Denmark
- Department of Clinical Medicine, Aarhus University, 8200 Aarhus N, Denmark
| | - Jacob Horsager
- Department of Nuclear Medicine and PET, Aarhus University Hospital, 8200 Aarhus N, Denmark
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Phukan BC, Roy R, Paul R, Mazumder MK, Nath J, Bhattacharya P, Borah A. Traversing through the cell signaling pathways of neuroprotection by betanin: therapeutic relevance to Alzheimer's Disease and Parkinson's Disease. Metab Brain Dis 2023; 38:805-817. [PMID: 36745251 DOI: 10.1007/s11011-023-01177-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 01/23/2023] [Indexed: 02/07/2023]
Abstract
Modulation of cell signaling pathways is the key area of research towards the treatment of neurodegenerative disorders. Altered Nrf2-Keap1-ARE (Nuclear factor erythroid-2-related factor 2-Kelch-like ECH-associated protein 1-Antioxidant responsive element) and SIRT1 (Sirtuin 1) cell signaling pathways are considered to play major role in the etiology and pathogenesis of Alzheimer's disease (AD) and Parkinson's disease (PD). Strikingly, betanin, a betanidin 5-O-β-D-glucoside compound is reported to show commendable anti-oxidative, anti-inflammatory and anti-apoptotic effects in several disease studies including AD and PD. The present review discusses the pre-clinical studies demonstrating the neuroprotective effects of betanin by virtue of its potential to ameliorate oxidative stress, neuroinflammation, abnormal protein aggregation and cell death. It highlights the direct linkage between the neuroprotective abilities of betanin and upregulation of the Nrf2-Keap1-ARE and SIRT1 signaling pathways. The review further hypothesizes the involvement of the betanin-Nrf2-ARE route in the inhibition of beta-amyloid aggregation through beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), one of the pivotal hallmarks of AD. The present review hereby for the first time elaborately discusses the reported neuroprotective abilities of betanin and decodes the Nrf2 and SIRT1 modulating potential of betanin as a primary mechanism of action behind, hence highlighting it as a novel drug candidate for the treatment of neurodegenerative diseases in the near future.
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Affiliation(s)
- Banashree Chetia Phukan
- Cellular and Molecular Neurobiology Laboratory, Department of Life Science and Bioinformatics, Assam University, Silchar, Assam, India, 788011
| | - Rubina Roy
- Cellular and Molecular Neurobiology Laboratory, Department of Life Science and Bioinformatics, Assam University, Silchar, Assam, India, 788011
| | - Rajib Paul
- Department of Zoology, Pandit Deendayal Upadhyaya Adarsha Mahavidyalaya (PDUAM), Eraligool, Karimganj, Assam, India, 788723
| | | | - Joyobrato Nath
- Department of Zoology, Cachar College, Silchar, Assam, India, 788001
| | - Pallab Bhattacharya
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, 382355, Gandhinagar, Gujarat, India
| | - Anupom Borah
- Cellular and Molecular Neurobiology Laboratory, Department of Life Science and Bioinformatics, Assam University, Silchar, Assam, India, 788011.
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Roy R, Bhattacharya P, Borah A. Targeting the Pathological Hallmarks of Alzheimer's Disease Through Nanovesicleaided Drug Delivery Approach. Curr Drug Metab 2022; 23:693-707. [PMID: 35619248 DOI: 10.2174/1389200223666220526094802] [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: 01/23/2022] [Revised: 02/23/2022] [Accepted: 03/02/2022] [Indexed: 01/05/2023]
Abstract
INTRODUCTION Nanovesicle technology is making a huge contribution to the progress of treatment studies for various diseases, including Alzheimer's disease (AD). AD is the leading neurodegenerative disorder characterized by severe cognitive impairment. Despite the prevalence of several forms of anti-AD drugs, the accelerating pace of AD incidence cannot becurbed, and for rescue, nanovesicle technology has grabbed much attention. METHODOLOGY Comprehensive literature search was carried out using relevant keywords and online database platforms. The main concepts that have been covered included a complex pathomechanism underlying increased acetylcholinesterase (AchE) activity, β-amyloid aggregation, and tau-hyperphosphorylation forming neurofibrillary tangles (NFTs) in the brain, which are amongst the major hallmarks of AD pathology. Therapeutic recommendations exist in the form of AchE inhibitors, along with anti-amyloid and anti-tau therapeutics, which are being explored at a high pace. The degree of the therapeutic outcome, however, gets restricted by the pharmacological limitations. Susceptibility to peripheral metabolism and rapid elimination, inefficiency to cross the blood-brain barrier (BBB) and reach the target brain site are the factors that lower the biostability and bioavailability of anti-AD drugs. The nanovesicle technology has emerged as a route to preserve the therapeutic efficiency of the anti-AD drugs and promote AD treatment. The review hereby aims to summarize the developments made by the nanovesicle technology in aiding the delivery of synthetic and plant-based therapeutics targeting the molecular mechanism of AD pathology. CONCLUSION Nanovesicles appear to efficiently aid in target-specific delivery of anti-AD therapeutics and nullify the drawbacks posed by free drugs, besides reducing the dosage requirement and the adversities associated. In addition, the nanovesicle technology also appears to uplift the therapeutic potential of several phyto-compounds with immense anti-AD properties. Furthermore, the review also sheds light on future perspectives to mend the gaps that prevail in the nanovesicle-mediated drug delivery in AD treatment strategies.
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Affiliation(s)
- Rubina Roy
- Department of Life Science and Bioinformatics, Cellular and Molecular Neurobiology Laboratory, Assam University, Silchar- 788011, Assam, India
| | - Pallab Bhattacharya
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad - 382355, Gandhinagar, Gujarat, India
| | - Anupom Borah
- Department of Life Science and Bioinformatics, Cellular and Molecular Neurobiology Laboratory, Assam University, Silchar- 788011, Assam, India
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Chiang NN, Lin TH, Teng YS, Sun YC, Chang KH, Lin CY, Hsieh-Li HM, Su MT, Chen CM, Lee-Chen GJ. Flavones 7,8-DHF, Quercetin, and Apigenin Against Tau Toxicity via Activation of TRKB Signaling in ΔK280 Tau RD-DsRed SH-SY5Y Cells. Front Aging Neurosci 2022; 13:758895. [PMID: 34975454 PMCID: PMC8714935 DOI: 10.3389/fnagi.2021.758895] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Accepted: 11/17/2021] [Indexed: 12/28/2022] Open
Abstract
Alzheimer’s disease (AD) is a progressive neurodegenerative disease with memory loss and cognitive decline. Neurofibrillary tangles (NFTs) formed by hyperphosphorylated Tau protein are one of the pathological hallmarks of several neurodegenerative diseases including AD. Heat shock protein family B (small) member 1 (HSPB1) is a molecular chaperone that promotes the correct folding of other proteins in response to environmental stress. Nuclear factor erythroid 2-like 2 (NRF2), a redox-regulated transcription factor, is the master regulator of the cellular response to excess reactive oxygen species. Tropomyosin-related kinase B (TRKB) is a membrane-bound receptor that, upon binding brain-derived neurotrophic factor (BDNF), phosphorylates itself to initiate downstream signaling for neuronal survival and axonal growth. In this study, four natural flavones such as 7,8-dihydroxyflavone (7,8-DHF), wogonin, quercetin, and apigenin were evaluated for Tau aggregation inhibitory activity and neuroprotection in SH-SY5Y neuroblastoma. Among the tested flavones, 7,8-DHF, quercetin, and apigenin reduced Tau aggregation, oxidative stress, and caspase-1 activity as well as improved neurite outgrowth in SH-SY5Y cells expressing ΔK280 TauRD-DsRed folding reporter. Treatments with 7,8-DHF, quercetin, and apigenin rescued the reduced HSPB1 and NRF2 and activated TRKB-mediated extracellular signal-regulated kinase (ERK) signaling to upregulate cAMP-response element binding protein (CREB) and its downstream antiapoptotic BCL2 apoptosis regulator (BCL2). Knockdown of TRKB attenuated the neuroprotective effects of these three flavones. Our results suggest 7,8-DHF, quercetin, and apigenin targeting HSPB1, NRF2, and TRKB to reduce Tau aggregation and protect cells against Tau neurotoxicity and may provide new treatment strategies for AD.
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Affiliation(s)
- Ni-Ni Chiang
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Te-Hsien Lin
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Yu-Shan Teng
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Ying-Chieh Sun
- Department of Chemistry, National Taiwan Normal University, Taipei, Taiwan
| | - Kuo-Hsuan Chang
- Department of Neurology, Chang Gung Memorial Hospital, Chang Gung University School of Medicine, Taoyuan, Taiwan
| | - Chung-Yin Lin
- Medical Imaging Research Center, Institute for Radiological Research, Chang Gung Memorial Hospital, Chang Gung University, Taoyuan, Taiwan
| | - Hsiu Mei Hsieh-Li
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Ming-Tsan Su
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Chiung-Mei Chen
- Department of Neurology, Chang Gung Memorial Hospital, Chang Gung University School of Medicine, Taoyuan, Taiwan
| | - Guey-Jen Lee-Chen
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
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Richter N, Nellessen N, Dronse J, Dillen K, Jacobs HIL, Langen KJ, Dietlein M, Kracht L, Neumaier B, Fink GR, Kukolja J, Onur OA. Spatial distributions of cholinergic impairment and neuronal hypometabolism differ in MCI due to AD. NEUROIMAGE-CLINICAL 2019; 24:101978. [PMID: 31422337 PMCID: PMC6706587 DOI: 10.1016/j.nicl.2019.101978] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 07/24/2019] [Accepted: 08/08/2019] [Indexed: 12/31/2022]
Abstract
Elucidating the relationship between neuronal metabolism and the integrity of the cholinergic system is prerequisite for a profound understanding of cholinergic dysfunction in Alzheimer's disease. The cholinergic system can be investigated specifically using positron emission tomography (PET) with [11C]N-methyl-4-piperidyl-acetate (MP4A), while neuronal metabolism is often assessed with 2-deoxy-2-[18F]fluoro-d-glucose-(FDG) PET. We hypothesised a close correlation between MP4A-perfusion and FDG-uptake, permitting inferences about metabolism from MP4A-perfusion, and investigated the patterns of neuronal hypometabolism and cholinergic impairment in non-demented AD patients. MP4A-PET was performed in 18 cognitively normal adults and 19 patients with mild cognitive impairment (MCI) and positive AD biomarkers. In nine patients with additional FDG-PET, the sum images of every combination of consecutive early MP4A-frames were correlated with FDG-scans to determine the optimal time window for assessing MP4A-perfusion. Acetylcholinesterase (AChE) activity was estimated using a 3-compartmental model. Group comparisons of MP4A-perfusion and AChE-activity were performed using the entire sample. The highest correlation between MP4A-perfusion and FDG-uptake across the cerebral cortex was observed 60-450 s after injection (r = 0.867). The patterns of hypometabolism (FDG-PET) and hypoperfusion (MP4A-PET) in MCI covered areas known to be hypometabolic early in AD, while AChE activity was mainly reduced in the lateral temporal cortex and the occipital lobe, sparing posterior midline structures. Data indicate that patterns of cholinergic impairment and neuronal hypometabolism differ significantly at the stage of MCI in AD, implying distinct underlying pathologies, and suggesting potential predictors of the response to cholinergic pharmacotherapy.
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Affiliation(s)
- Nils Richter
- Department of Neurology, University Hospital Cologne, 50937 Cologne, Germany; Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Center Jülich, 52425 Jülich, Germany; Max-Planck-Institute for Metabolism Research, 50937 Cologne, Germany.
| | - Nils Nellessen
- Department of Neurology, University Hospital Cologne, 50937 Cologne, Germany; Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Center Jülich, 52425 Jülich, Germany
| | - Julian Dronse
- Department of Neurology, University Hospital Cologne, 50937 Cologne, Germany; Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Center Jülich, 52425 Jülich, Germany
| | - Kim Dillen
- Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Center Jülich, 52425 Jülich, Germany
| | - Heidi I L Jacobs
- Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Center Jülich, 52425 Jülich, Germany; Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, Boston, MA, United States of America; The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, Boston, MA, United States of America; Faculty of Health, Medicine and Life Sciences, School for Mental Health and Neuroscience, Alzheimer Centre Limburg, Maastricht University, Maastricht, the Netherlands
| | - Karl-Josef Langen
- Medical Imaging Physics (INM-4), Institute of Neuroscience and Medicine (INM-4), Research Center Jülich, 52425 Jülich, Germany
| | - Markus Dietlein
- Department of Nuclear Medicine, University Hospital Cologne, 50937 Cologne, Germany
| | - Lutz Kracht
- Max-Planck-Institute for Metabolism Research, 50937 Cologne, Germany; Department of Nuclear Medicine, University Hospital Cologne, 50937 Cologne, Germany
| | - Bernd Neumaier
- Institute for Radiochemistry and Experimental Molecular Imaging, University Hospital Cologne, 50937 Cologne, Germany; Nuclear Chemistry, Institute of Neuroscience and Medicine (INM-5), Research Center Jülich, 52425 Jülich, Germany
| | - Gereon R Fink
- Department of Neurology, University Hospital Cologne, 50937 Cologne, Germany; Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Center Jülich, 52425 Jülich, Germany
| | - Juraj Kukolja
- Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Center Jülich, 52425 Jülich, Germany; Department of Neurology and Neurophysiology, Helios University Hospital Wuppertal, 42283 Wuppertal, Germany
| | - Oezguer A Onur
- Department of Neurology, University Hospital Cologne, 50937 Cologne, Germany; Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Center Jülich, 52425 Jülich, Germany
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Meng D, Li X, Bauer M, Taylor JP, Auer DP. Altered Nucleus Basalis Connectivity Predicts Treatment Response in Mild Cognitive Impairment. Radiology 2018; 289:775-785. [PMID: 30204076 PMCID: PMC6283326 DOI: 10.1148/radiol.2018180092] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 07/03/2018] [Accepted: 07/18/2018] [Indexed: 11/11/2022]
Abstract
Purpose To determine whether functional connectivity (FC) mapping of nucleus basalis of Meynert (NBM) cholinergic network (hereafter, NBM FC) could provide a biomarker of central cholinergic deficits with predictive potential for response to cholinesterase inhibitor (ChEI) treatment. Materials and Methods The Alzheimer's Disease Neuroimaging Initiative (ADNI) was approved by the institutional review boards of all participating sites. All participants and their representatives gave written informed consent prior to data collection. NBM FC was examined in 33 healthy control participants, 102 patients with mild cognitive impairment (MCI), and 33 patients with AD by using resting-state functional MRI data from the ADNI database. NBM FC was compared between groups before and after 6 months of ChEI treatment in MCI. Associations between baseline NBM FC and baseline cognitive performance as well as cognitive outcomes after treatment were investigated. Results Compared with the healthy control group, NBM FC was decreased in patients with untreated MCI and increased in patients with AD treated with ChEI (corrected P ˂ .05). Global cognition (Alzheimer's Disease Assessment Scale-Cognitive subscale score) was associated with NBM FC (r = -0.349; P ˂ .001). NBM FC was higher 6 months after ChEI compared with before ChEI in treated MCI (corrected P ˂ .05), but did not change at 6 months in patients with untreated MCI (corrected P ˂ .05). Baseline NBM FC in MCI strongly predicted cognitive outcomes 6 months after ChEI (R2 = 0.458; P = .001). Conclusion Functional dissociation of the nucleus basalis of Meynert from a cortical network may explain the cognitive deficits in dementia and allow for the selection of individuals who are more likely to respond to cholinesterase inhibitors at early disease stages. © RSNA, 2018 Online supplemental material is available for this article.
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Affiliation(s)
- Dewen Meng
- From the Sir Peter Mansfield Imaging Centre, School of Medicine
(D.M., X.L., D.P.A.), and School of Psychology (M.B.), University of Nottingham,
Nottingham, England; NIHR Nottingham Biomedical Research Centre, Queen’s
Medical Centre, University of Nottingham, Derby Rd, Nottingham NG7 2UH, England
(D.M., X.L., D.P.A.); and Institute of Neuroscience, Newcastle University,
Campus for Ageing and Vitality, Newcastle upon Tyne, England (J.P.T.)
| | - Xingfeng Li
- From the Sir Peter Mansfield Imaging Centre, School of Medicine
(D.M., X.L., D.P.A.), and School of Psychology (M.B.), University of Nottingham,
Nottingham, England; NIHR Nottingham Biomedical Research Centre, Queen’s
Medical Centre, University of Nottingham, Derby Rd, Nottingham NG7 2UH, England
(D.M., X.L., D.P.A.); and Institute of Neuroscience, Newcastle University,
Campus for Ageing and Vitality, Newcastle upon Tyne, England (J.P.T.)
| | - Markus Bauer
- From the Sir Peter Mansfield Imaging Centre, School of Medicine
(D.M., X.L., D.P.A.), and School of Psychology (M.B.), University of Nottingham,
Nottingham, England; NIHR Nottingham Biomedical Research Centre, Queen’s
Medical Centre, University of Nottingham, Derby Rd, Nottingham NG7 2UH, England
(D.M., X.L., D.P.A.); and Institute of Neuroscience, Newcastle University,
Campus for Ageing and Vitality, Newcastle upon Tyne, England (J.P.T.)
| | - John-Paul Taylor
- From the Sir Peter Mansfield Imaging Centre, School of Medicine
(D.M., X.L., D.P.A.), and School of Psychology (M.B.), University of Nottingham,
Nottingham, England; NIHR Nottingham Biomedical Research Centre, Queen’s
Medical Centre, University of Nottingham, Derby Rd, Nottingham NG7 2UH, England
(D.M., X.L., D.P.A.); and Institute of Neuroscience, Newcastle University,
Campus for Ageing and Vitality, Newcastle upon Tyne, England (J.P.T.)
| | - Dorothee P. Auer
- From the Sir Peter Mansfield Imaging Centre, School of Medicine
(D.M., X.L., D.P.A.), and School of Psychology (M.B.), University of Nottingham,
Nottingham, England; NIHR Nottingham Biomedical Research Centre, Queen’s
Medical Centre, University of Nottingham, Derby Rd, Nottingham NG7 2UH, England
(D.M., X.L., D.P.A.); and Institute of Neuroscience, Newcastle University,
Campus for Ageing and Vitality, Newcastle upon Tyne, England (J.P.T.)
| | - For the Alzheimer's Disease Neuroimaging Initiative
- From the Sir Peter Mansfield Imaging Centre, School of Medicine
(D.M., X.L., D.P.A.), and School of Psychology (M.B.), University of Nottingham,
Nottingham, England; NIHR Nottingham Biomedical Research Centre, Queen’s
Medical Centre, University of Nottingham, Derby Rd, Nottingham NG7 2UH, England
(D.M., X.L., D.P.A.); and Institute of Neuroscience, Newcastle University,
Campus for Ageing and Vitality, Newcastle upon Tyne, England (J.P.T.)
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Kikuchi T, Okamura T, Zhang MR, Irie T. PET probes for imaging brain acetylcholinesterase. J Labelled Comp Radiopharm 2013; 56:172-9. [DOI: 10.1002/jlcr.3002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 11/08/2012] [Accepted: 11/08/2012] [Indexed: 12/31/2022]
Affiliation(s)
- Tatsuya Kikuchi
- Probe Research Team, Molecular Probe Program, Molecular Imaging Center; National Institute of Radiological Sciences; Chiba; 263-8555; Japan
| | - Toshimitsu Okamura
- Probe Research Team, Molecular Probe Program, Molecular Imaging Center; National Institute of Radiological Sciences; Chiba; 263-8555; Japan
| | - Ming-Rong Zhang
- Probe Research Team, Molecular Probe Program, Molecular Imaging Center; National Institute of Radiological Sciences; Chiba; 263-8555; Japan
| | - Toshiaki Irie
- Probe Research Team, Molecular Probe Program, Molecular Imaging Center; National Institute of Radiological Sciences; Chiba; 263-8555; Japan
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Foster PS, Branch KK, Witt JC, Giovannetti T, Libon D, Heilman KM, Drago V. Acetylcholinesterase inhibitors reduce spreading activation in dementia. Neuropsychologia 2012; 50:2093-9. [DOI: 10.1016/j.neuropsychologia.2012.05.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Revised: 04/09/2012] [Accepted: 05/08/2012] [Indexed: 11/28/2022]
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Carvajal FJ, Inestrosa NC. Interactions of AChE with Aβ Aggregates in Alzheimer's Brain: Therapeutic Relevance of IDN 5706. Front Mol Neurosci 2011; 4:19. [PMID: 21949501 PMCID: PMC3172730 DOI: 10.3389/fnmol.2011.00019] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Accepted: 08/21/2011] [Indexed: 12/20/2022] Open
Abstract
Acetylcholinesterase (AChE; EC 3.1.1.7) plays a crucial role in the rapid hydrolysis of the neurotransmitter acetylcholine, in the central and peripheral nervous system and might also participate in non-cholinergic mechanism related to neurodegenerative diseases. Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by a progressive deterioration of cognitive abilities, amyloid-β (Aβ) peptide accumulation and synaptic alterations. We have previously shown that AChE is able to accelerate the Aβ peptide assembly into Alzheimer-type aggregates increasing its neurotoxicity. Furthermore, AChE activity is altered in brain and blood of Alzheimer’s patients. The enzyme associated to amyloid plaques changes its enzymatic and pharmacological properties, as well as, increases its resistant to low pH, inhibitors and excess of substrate. Here, we reviewed the effects of IDN 5706, a hyperforin derivative that has potential preventive effects on the development of AD. Our results show that treatment with IDN 5706 for 10 weeks increases brain AChE activity in 7-month-old double transgenic mice (APPSWE–PS1) and decreases the content of AChE associated with different types of amyloid plaques in this Alzheimer’s model. We concluded that early treatment with IDN 5706 decreases AChE–Aβ interaction and this effect might be of therapeutic interest in the treatment of AD.
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Affiliation(s)
- Francisco J Carvajal
- Centro de Envejecimiento y Regeneración (CARE), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile Santiago, Chile
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In vivo imaging of synaptic function in the central nervous system. Behav Brain Res 2009; 204:1-31. [DOI: 10.1016/j.bbr.2009.06.008] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2009] [Revised: 05/27/2009] [Accepted: 06/02/2009] [Indexed: 01/07/2023]
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Dome P, Lazary J, Kalapos MP, Rihmer Z. Smoking, nicotine and neuropsychiatric disorders. Neurosci Biobehav Rev 2009; 34:295-342. [PMID: 19665479 DOI: 10.1016/j.neubiorev.2009.07.013] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 07/23/2009] [Accepted: 07/30/2009] [Indexed: 12/20/2022]
Abstract
Tobacco smoking is an extremely addictive and harmful form of nicotine (NIC) consumption, but unfortunately also the most prevalent. Although disproportionately high frequencies of smoking and its health consequences among psychiatric patients are widely known, the neurobiological background of this epidemiological association is still obscure. The diverse neuroactive effects of NIC and some other major tobacco smoke constituents in the central nervous system may underlie this association. This present paper summarizes the pharmacology of NIC and its receptors (nAChR) based on a systematic review of the literature. The role of the brain's reward system(s) in NIC addiction and the results of functional and structural neuroimaging studies on smoking-related states and behaviors (i.e. dependence, craving, withdrawal) are also discussed. In addition, the epidemiological, neurobiological, and genetic aspects of smoking in several specific neuropsychiatric disorders are reviewed and the clinical relevance of smoking in these disease states addressed.
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Affiliation(s)
- Peter Dome
- Department of Clinical and Theoretical Mental Health, Kutvolgyi Clinical Center, Semmelweis University, Faculty of Medicine, Kutvolgyi ut 4, 1125 Budapest, Hungary.
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13
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Kim JS, Oh SJ, Moon DH. Molecular Imaging in Neurodegenerative Diseases. JOURNAL OF THE KOREAN MEDICAL ASSOCIATION 2009. [DOI: 10.5124/jkma.2009.52.2.151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Jae Seung Kim
- Department of Nuclear Medicine, University of Ulsan College of Medicine, Korea. , ,
| | - Seung Jun Oh
- Department of Nuclear Medicine, University of Ulsan College of Medicine, Korea. , ,
| | - Dae Hyuk Moon
- Department of Nuclear Medicine, University of Ulsan College of Medicine, Korea. , ,
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14
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Herholz K. Acetylcholine esterase activity in mild cognitive impairment and Alzheimer's disease. Eur J Nucl Med Mol Imaging 2008; 35 Suppl 1:S25-9. [PMID: 18196237 DOI: 10.1007/s00259-007-0699-4] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
PURPOSE Impairment of cholinergic neurotransmission is a well-established fact in Alzheimer's disease (AD), but there is controversy about its relevance at the early stages of the disease and in mild cognitive impairment (MCI). METHODS In vivo positron emission tomography imaging of cortical acetylcholine esterase (AChE) activity as a marker of cholinergic innervation that is expressed by cholinergic axons and cholinoceptive neurons has demonstrated a reduction of this enzyme activity in manifest AD. The technique is also useful to measure the inhibition of cerebral AChE induced by cholinesterase inhibitors for treatment of dementia symptoms. RESULTS A reduction of cortical AchE activity was found consistently in all studies of AD and in few cases of MCI who later concerted to AD. CONCLUSION The in vivo findings in MCI and very mild AD are still preliminary, and studies seem to suggest that cholinergic innervation and AChE as the main degrading enzyme are both reduced, which might result in partial compensation of their effect.
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Affiliation(s)
- Karl Herholz
- Wolfson Molecular Imaging Centre, Clinical Neuroscience, University of Manchester, 27 Palatine Road, Manchester, UK.
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15
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Cohen RM. The application of positron-emitting molecular imaging tracers in Alzheimer's disease. Mol Imaging Biol 2007; 9:204-16. [PMID: 17354042 DOI: 10.1007/s11307-007-0094-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The symptomatology and known pathology of Alzheimer's disease are restricted to the central nervous system. This review details studies of PET tracers aimed at interrogating cholinergic, serotonergic, opiate, benzodiazepine, and inflammatory pathways as well as PET tracers that illuminate amyloid plaques and neurofibrillary tangles in AD. Progress has been remarkable. Together with studies of brain structure with MRI and of functional regional brain activity, e.g., through measures of blood flow and glucose metabolic rate, molecular imaging promises to dramatically alter our understanding of the structural and physiological abnormalities underlying AD symptomatology. A more immediate impact on the diagnosis and treatment evaluation of AD patients in clinical trials is predicted while the possibility of personalized treatment or prevention of AD may not be that far away.
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Affiliation(s)
- Robert M Cohen
- Department of Psychiatry and Behavioral Neurosciences, Cedars-Sinai Medical Center, Thalians E-135, Los Angeles, CA 90048, USA.
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16
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Eggers C, Herholz K, Kalbe E, Heiss WD. Cortical acetylcholine esterase activity and ApoE4-genotype in Alzheimer disease. Neurosci Lett 2006; 408:46-50. [PMID: 16996687 DOI: 10.1016/j.neulet.2006.08.061] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 08/12/2006] [Accepted: 08/14/2006] [Indexed: 10/24/2022]
Abstract
Positron emission tomography (PET) studies have demonstrated reduced acetylcholine esterase (AChE) activity as an indicator of cholinergic impairment, which is a main pathogenic process in Alzheimer's disease (AD). The E4 allele of apolipoprotein epsilon (ApoE4) is a major risk factor for AD. We examined the relation between ApoE-genotype and cortical AChE activity. In 19 patients (mean age 64) with mild to moderate AD (mean MMSE 22) PET with C-11-labeled N-methyl-4-piperidyl-acetate (MP4A) was performed and the ApoE4-genotype was determined. Parametric images of AChE hydrolysis were generated using a non-invasive technique and analysed globally and regionally. A neuropsychological battery testing memory, attention, executive functions, visuoconstruction, and language was administered. The mean cortical AChE activity was reduced significantly in both groups compared to reference values. The ApoE4 positive subjects (two homozygotes, nine heterozygotes) had significantly higher (p<0.05) AChE levels (MP4A hydrolysis rate 0.0753+/-0.0088min(-1)) than the ApoE4 negative subjects (n=8, 0.0654+/-0.0090min(-1)). Both groups were comparable with regard to age (63 versus 65) and dementia severity (MMSE 20 versus MMSE 22). AChE-impairment correlated significantly with the word fluency task (r=0.041, p<0.05) in the ApoE4 negative group only. These results indicate that cortical AChE activity is relatively well preserved in ApoE4 carriers, either by preservation of its cellular expression or as AChE activity in amyloid plaques.
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17
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Babiloni C, Cassetta E, Dal Forno G, Del Percio C, Ferreri F, Ferri R, Lanuzza B, Miniussi C, Moretti DV, Nobili F, Pascual-Marqui RD, Rodriguez G, Luca Romani G, Salinari S, Zanetti O, Rossini PM. Donepezil effects on sources of cortical rhythms in mild Alzheimer's disease: Responders vs. Non-Responders. Neuroimage 2006; 31:1650-65. [PMID: 16600641 DOI: 10.1016/j.neuroimage.2006.02.015] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2005] [Revised: 02/01/2006] [Accepted: 02/03/2006] [Indexed: 11/20/2022] Open
Abstract
Acetylcholinesterase inhibitors (AChEI) such as donepezil act in mild Alzheimer's disease (AD) by increasing cholinergic tone. Differences in the clinical response in patients who do or do not benefit from therapy may be due to different functional features of the central neural systems. We tested this hypothesis using cortical electroencephalographic (EEG) rhythmicity. Resting eyes-closed EEG data were recorded in 58 mild AD patients (Mini Mental State Examination [MMSE] range 17-24) before and approximately 1 year after standard donepezil treatment. Based on changes of MMSE scores between baseline and follow-up, 28 patients were classified as "Responders" (MMSEvar >or=0) and 30 patients as "Non-Responders" (MMSEvar <0). EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). Cortical EEG sources were studied with low-resolution brain electromagnetic tomography (LORETA). Before treatment, posterior sources of delta, alpha 1 and alpha 2 frequencies were greater in amplitude in Non-Responders. After treatment, a lesser magnitude reduction of occipital and temporal alpha 1 sources characterized Responders. These results suggest that Responders and Non-Responders had different EEG cortical rhythms. Donepezil could act by reactivating existing yet functionally silent cortical synapses in Responders, restoring temporal and occipital alpha rhythms.
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Affiliation(s)
- Claudio Babiloni
- Dip. Fisiologia Umana e Farmacologia, Univ. La Sapienza, Rome, Italy.
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18
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Abstract
PURPOSE OF REVIEW Mild cognitive impairment often represents the earliest clinical phase of Alzheimer's disease and is thought to involve synaptic dysfunction. Functional neuroimaging methods may be sensitive to these early physiologic changes and may be useful in early detection, therapeutic monitoring, and prediction of treatment response and other clinical outcomes. This review will focus on functional magnetic resonance imaging and its use in measuring the effects of cholinergic modulation in mild cognitive impairment. RECENT FINDINGS Functional magnetic resonance imaging has begun to be applied to measure changes in regional brain activation during cognitive task performance after pharmacologic manipulation. In mild cognitive impairment, recent reports have appeared demonstrating alterations in neocortical activation after acute and prolonged administration of acetylcholinesterase inhibitors. These functional changes may relate to both behavioral performance and measures of brain structure (e.g., hippocampal volume). SUMMARY Pharmacologic functional magnetic resonance imaging is a rapidly emerging field, with applications in both basic human neuroscience and clinical psychiatry and neurology. Its use in mild cognitive impairment and Alzheimer's disease may provide novel insights into the cholinergic system, memory, and neurodegenerative disease.
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Affiliation(s)
- Bradford C Dickerson
- Gerontology Research Unit, Department of Neurology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA 02129, USA.
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Shao X, Koeppe RA, Butch ER, Kilbourn MR, Snyder SE. Evaluation of 18F-labeled acetylcholinesterase substrates as PET radiotracers. Bioorg Med Chem 2005; 13:869-75. [PMID: 15653352 DOI: 10.1016/j.bmc.2004.10.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2004] [Revised: 10/14/2004] [Accepted: 10/14/2004] [Indexed: 11/24/2022]
Abstract
Four 18F-labeled acetylcholinesterase (AChE) substrates, (S)-N-[18F]fluoroethyl-2-piperidinemethyl acetate (1), (R)-N-[18F]fluoroethyl-3-pyrrolidinyl acetate (2), N-[18F]fluoroethyl-4-piperidinyl acetate (3), and (R)-N-[18F]fluoroethyl-3-piperidinyl acetate (4), were evaluated for in vivo blood and brain metabolism in mice, brain pharmacokinetics in rats monkeys (M. nemistrina) using PET imaging. All 18F-labeled compounds were compared to N-[11C]methyl-4-piperidinyl propionate (PMP). Compound 1 was completely metabolized within 1 min in mouse blood and brain. This compound had relatively fast regional brain pharmacokinetics and poor discrimination between brain regions with different AChE concentration. Compound 4 showed relatively slower blood metabolism and slower pharmacokinetics than compound 1 but again poor discrimination between brain regions. Both compounds 1 and 4 showed different kinetic profiles than PMP in PET studies. Compound 3 had the slowest blood metabolism and slower pharmacokinetics than PMP. Compound 2 showed highly encouraging characteristics with an in vivo metabolism rate, primate brain uptake, and regional brain pharmacokinetics similar to [11C]PMP. The apparent hydrolysis rate constant k3 in primate cortex was very close to that of [11C]PMP. This compound has potential to be a good PET radiotracer for measuring brain AChE activity. The longer lifetime of 18F would permit longer imaging times and allows preparation of radiotracer batches for multiple patients and delivery of the tracer to other facilities, making the technique more widely available to clinical investigators.
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Affiliation(s)
- Xia Shao
- Division of Nuclear Medicine, Department of Radiology, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
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20
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Newberg AB, Alavi A. The role of PET imaging in the management of patients with central nervous system disorders. Radiol Clin North Am 2005; 43:49-65. [PMID: 15693647 DOI: 10.1016/j.rcl.2004.09.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PET will continue to play a critical role in both clinical and research applications with regard to CNS disorders. PET is useful in the initial diagnosis of patients presenting with CNS symptoms and can help clinicians determine the best course of therapy. PET studies can also be useful for studying the response to therapy. From the research perspective, the various neurotransmitter and other molecular tracers currently available or in development will provide substantial information about pathophysiologic process in the brain. As such applications become more widely tested, their introduction into the clinical arena will further advance the use of PET imaging in the evaluation and management of CNS disorders.
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Affiliation(s)
- Andrew B Newberg
- Division of Nuclear Medicine, Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, 110 Donner Building, Philadelphia, PA 19104, USA.
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21
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Rodriguez G, Vitali P, Canfora M, Calvini P, Girtler N, De Leo C, Piccardo A, Nobili F. Quantitative EEG and perfusional single photon emission computed tomography correlation during long-term donepezil therapy in Alzheimer's disease. Clin Neurophysiol 2004; 115:39-49. [PMID: 14706467 DOI: 10.1016/s1388-2457(03)00321-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE There is an increasing interest in the effects of the acetylcholinesterase inhibitors (AChEIs) in Alzheimer's disease (AD), as investigated by means of objective, neurophysiological tools. In an open-label study, we evaluated the neurophysiological effects of chronic administration of donepezil to AD patients, by means of a correlative approach between quantitative EEG (qEEG) and perfusional brain single photon emission computed tomography (SPECT). METHODS Sixteen patients (mean age: 74.8+/-7.9 years) with mild to moderate AD (MMSE score >13, mean: 20.7+/-4.6) underwent qEEG and SPECT examinations at the time of diagnosis (t0) and after approximately 1 year of donepezil therapy (t1). The brain SPECT (99mTc-hexamethylpropyleneamine oxime) was performed by means of a high-resolution SPECT camera; the qEEG was recorded from 19 scalp electrodes by average reference and digitized at 512 Hz. The mean frequency (MF) value of the mean power spectrum (fast Fourier transform) from 4 brain regions (one frontal and one temporal-parietal in each hemisphere) was chosen for statistical analysis. Changes in MMSE score and qEEG-MF values between t0 and t1 were assessed by analysis of variance. SPECT differences between t0 and t1, as well as the relationships between SPECT and qEEG changes, were assessed by statistical parametric mapping (SPM 99; height threshold: P=0.001 at cluster level). RESULTS Between t0 and t1, the MMSE score significantly (P<0.05) decreased (from 20.7+/-4.64 to 19.1+/-5.09; 95% confidence interval: 1.14) and qEEG was unchanged. There was no regional perfusion decrease; a small area of relative perfusion increase was observed, including the right occipital cuneus and the left lingual gyrus. A positive correlation was found between the right frontal MF and brain perfusion in the left superior parietal lobule. A post hoc SPM analysis (height threshold: P=0.01) showed a positive correlation between brain perfusion and each of the 4 qEEG MF values in the left parietal lobe, including the precuneus, the superior parietal lobule, and the post-central gyrus. CONCLUSIONS The posterior parietal region, which is involved in memory and attention, is often affected by hypoperfusion in AD, as a likely consequence of disconnection from the atrophic mesial temporal cortex. Metabolic activation induced by AChEIs may especially influence this disconnected but still not grossly impaired area, which could be one of the pathophysiological substrates of the cognitive effects of AChEIs. The modest topographical sensitivity of qEEG, reflecting the rather diffuse changes in AD, is further confirmed.
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Affiliation(s)
- Guido Rodriguez
- Clinical Neurophysiology, Department of Internal Medicine, University of Genoa, Viale Benedetto XV 6, 16132 Genoa, Italy.
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22
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Cohen RM, Podruchny TA, Bokde ALW, Carson RE, Herscovitch P, Kiesewetter DO, Eckelman WC, Sunderland T. Higher in vivo muscarinic-2 receptor distribution volumes in aging subjects with an apolipoprotein E-epsilon4 allele. Synapse 2003; 49:150-6. [PMID: 12774299 DOI: 10.1002/syn.10225] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The apolipoprotein E-epsilon4 allele confers an increased susceptibility to age-related memory problems and Alzheimer's disease. Abnormalities in the cholinergic system are also likely contributors to memory deficits associated with aging and AD. To determine the effect of the APOE-epsilon4 allele on the muscarinic component of the cholinergic system of aging subjects, 10 healthy subjects with APOE-epsilon4 alleles (APOE-epsilon4+) and 10 without (APOE-epsilon4-), ranging in age from 52 to 75 years, were tomographically scanned with the F-18-labeled muscarinic-2 (M2) selective agonist, 3-(3-(3-[(18)F]Flouropropyl)thio)-1,2,5-thiadiazol-4-yl)-1,2,5,6-tetrahydro-1-methylpyridine ([(18)F]FP-TZTP). The distribution volumes (V(T)) of [(18)F]FP-TZTP were determined by compartmental modeling of partial volume and free fraction corrected PET scans. Regional cerebral blood flow (rCBF) measurements with H(2) (15)O were also performed. Global Gray V(T) (840 +/- 155 ml plasma/ml tissue) was greater in APOE-epsilon4+ subjects than APOE-epsilon4- subjects (660 +/- 113 ml plasma/ml tissue, P = 0.01), and previously studied younger subjects. There were no significant differences between the groups with respect to rCBF, but within the APOE-epsilon4+ group there was a trend for subjects with the higher Global Gray V(T)s to have lower Global Gray CBFs (r = -0.65, P < 0.06). A lower concentration of acetylcholine in the synapse of APOE-epsilon4+ older individuals is a likely explanation for the greater [(18)F]FP-TZTP distribution volumes.
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Affiliation(s)
- Robert M Cohen
- Geriatric Psychiatry Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, USA
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23
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Shao X, Butch ER, Kilbourn MR, Snyder SE. N-[(18)F]Fluoroethylpiperidinyl, N-[(18)F]fluoroethylpiperidinemethyl and N-[(18)F]fluoroethylpyrrolidinyl esters as radiotracers for acetylcholinesterase. Nucl Med Biol 2003; 30:491-500. [PMID: 12831986 DOI: 10.1016/s0969-8051(03)00031-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A series of N-fluoroethylpiperidinyl (1), N-fluoroethylpiperidinemethyl (2) and N-fluoroethylpyrrolidinyl (3) esters were synthesized and examined as new (18)F-labeled radiotracers for measuring brain cholinesterase activity. The fluoroethyl group, instead of methyl group, results in slower in vitro enzymatic cleavage rates and higher selectivity for AChE. Based on metabolism in mouse blood and PET time-activity curves in rats, two radiotracers were identified as potential candidates for further in vivo evaluation in higher species.
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Affiliation(s)
- Xia Shao
- Division of Nuclear Medicine, Department of Radiology, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
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24
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Shao X, Lisi JM, Butch ER, Kilbourn MR, Snyder SE. N-methylpiperidinemethyl, N-methylpyrrolidyl and N-methylpyrrolidinemethyl esters as PET radiotracers for acetylcholinesterase activity. Nucl Med Biol 2003; 30:293-302. [PMID: 12745021 DOI: 10.1016/s0969-8051(02)00438-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The N-[(11)C]methylpiperidinyl esters are used as radiopharmaceuticals for measuring brain cholinesterase activity. We have synthesized a series of N-methylpiperidinemethyl (1), N-methylpyrrolidinyl (2) and N-methylpyrrolidinemethyl (3) esters and examined the effects of sterric constraint and stereochemistry on cholinesterase-mediated cleavage. Acetylcholinesterase exhibited a preference for primary esters 1 and for the R-isomers of both 1 and 2. Biological data for (S)-N-[(11)C]methyl-2-piperidinemethyl acetate (1a) were similar to [(11)C]AMP. These data better define the structure-activity relationships for cholinesterase radiotracers and provide lead compounds for (18)F- labeling.
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Affiliation(s)
- Xia Shao
- Division of Nuclear Medicine, Department of Radiology, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
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25
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Tayebati SK, Amenta F, Amici S, El-Assouad D, Gallai V, Ricci A, Parnetti L. Peripheral blood lymphocytes muscarinic cholinergic receptor subtypes in Alzheimer's disease: a marker of cholinergic dysfunction? J Neuroimmunol 2001; 121:126-31. [PMID: 11730949 DOI: 10.1016/s0165-5728(01)00435-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Muscarinic M2-M5 muscarinic cholinergic receptors were investigated in peripheral blood lymphocytes of patients with mild cognitive impairment of the Alzheimer's type (MCIAT), probable Alzheimer's disease (AD) and probable vascular dementia (VaD). [3H]-N-methyl scopolamine (NMS) in the presence of muscarinic antagonists and Mamba venom to occlude different receptor subtypes was used as radioligand. Analysis of [3H]-NMS binding curves without receptor subtype assessment resulted in a slight decrease of receptor density in AD patients. Evaluation of receptor subtypes in MCIAT and AD patients revealed a decrease of M3 receptor by more than 50%, an increase of M4 receptor expression by about 20% and no changes of M2 or M5 receptors. The expression of M2-M5 receptors was unaltered in VaD patients. Strong positive and negative correlations respectively were found between the density of lymphocyte M3 and M4 receptors and MMSE score in both MCIAT (0.78 for M3 receptor and 0.80 for M4 receptor) and AD (0.82 for M3 receptor and 0.83 for M4 receptor) patients. These findings suggest that changes in the expression of peripheral blood lymphocyte M3 and M4 receptors in AD are related to the degree of cognitive impairment. Assessment of lymphocyte muscarinic receptor subtypes may contribute to characterization of cholinergic impairment in AD.
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Affiliation(s)
- S K Tayebati
- Sezione di Anatomia Umana, Dipartimento di Scienze Farmacologiche e Medicina Sperimentale, Università di Camerino, Via Scalzino, 3, 62032 Camerino, Italy.
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26
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Chu Y, Cochran EJ, Bennett DA, Mufson EJ, Kordower JH. Down-regulation of trkA mRNA within nucleus basalis neurons in individuals with mild cognitive impairment and Alzheimer's disease. J Comp Neurol 2001; 437:296-307. [PMID: 11494257 DOI: 10.1002/cne.1284] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Recent studies indicate that trkA expression is reduced in end-stage Alzheimer's disease (AD). However, understanding the neuropathologic correlates of early cognitive decline, as well as the changes that underlie the transition from nondemented mild cognitive impairment (MCI) to AD, are more critical neurobiological challenges. In these regards, the present study examined the expression of trkA mRNA in individuals diagnosed with MCI and AD from a cohort of people enrolled in a Religious Orders Study. Individuals with MCI and AD displayed significant reductions in trkA mRNA relative to aged-matched controls, indicating that alterations in trkA gene expression occur early in the disease process. The magnitude of change was similar in MCI and AD cases, suggesting that further loss of trkA mRNA is not necessarily associated with the transition of individuals from nondemented MCI to AD. The loss of trkA mRNA was not associated with education, apolipoprotein E allele status, gender, Braak score, global cognitive score or Mini-Mental Status Examination. In contrast, the loss of trkA mRNA in MCI and AD was significantly correlated with function on a variety of episodic memory tests.
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Affiliation(s)
- Y Chu
- Department of Neurological Sciences and Rush Alzheimer's Disease Center, Rush Presbyterian-St. Luke's Medical Center, Chicago, Illinois 60612, USA
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27
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Abstract
Neuroimaging methodologies have shown some of their greatest promise in studies of Alzheimer's disease (AD). Imaging outcome measures are now entering the arena of investigational trials for AD, to elucidate treatment mechanisms, optimize drug dosing, and perhaps serve as surrogate efficacy measures. Drugs that enhance central cholinergic neurotransmission have been extensively examined for their effects on regional cerebral blood flow, regional cerebral glucose metabolism, or levels of N-acetyl-aspartate in AD patients. Putative disease-modifying agents will be studied by structural magnetic resonance imaging for their ability to reduce rates of hippocampal or whole brain atrophy. When anti-amyloid therapies reach widespread clinical testing, their effects may be monitored by specific imaging probes for amyloid-beta peptide-containing senile plaques. Neuroimaging studies of AD patients and asymptomatic subjects who carry the apolipoprotein E e4 allele suggest that these individuals may be particularly suitable for testing candidate prevention therapies for AD.
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Affiliation(s)
- C H van Dyck
- Alzheimer's Disease Research Unit, CB 2041, Yale University School of Medicine, 1 Church Street, Suite 600, New Haven, CT 06510, USA.
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28
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Snyder SE, Gunupudi N, Sherman PS, Butch ER, Skaddan MB, Kilbourn MR, Koeppe RA, Kuhl DE. Radiolabeled cholinesterase substrates: in vitro methods for determining structure-activity relationships and identification of a positron emission tomography radiopharmaceutical for in vivo measurement of butyrylcholinesterase activity. J Cereb Blood Flow Metab 2001; 21:132-43. [PMID: 11176278 DOI: 10.1097/00004647-200102000-00004] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
There is currently great interest in developing radiolabeled substrates for acetylcholinesterase and butyrylcholinesterase that would be useful in the in vivo imaging of patients with Alzheimer's disease. Using a simple in vitro spectrophotometric assay for determination of enzymatic cleavage rates, the structure-activity relationship for a short series of 1-methyl-4-piperidinyl esters was investigated. Relative enzymatic hydrolysis rates for the well-characterized 1-methyl-4-piperidinyl acetate, propionate, and i-butyrate esters were in agreement with literature values. The 4 and 5 carbon esters of 1-methyl-4-piperidinol were specific for butyrylcholinesterase and cleaved in the rank order n-valerate > n-butyrate >> 2-methylbutyrate, iso-valerate. These spectrophotometric results were also in agreement with in vitro hydrolysis rates in mouse blood and with in vivo regional retention of radioactivity in mouse brain of 11C-labeled analogs. Brain uptake and apparent enzymatic rate constants for 1-[11C]methyl-4-piperidinyl n-butyrate and n-valerate were calculated from in vivo measurements in M. nemistrina using positron emission tomography. Based on higher brain uptake of radioactivity and superior pharmacokinetics, 1-[11C]methyl-4-piperidinyl n-butyrate was identified as a new radiopharmaceutical for the in vivo measurement of butyrylcholinesterase activity.
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Affiliation(s)
- S E Snyder
- Department of Radiology, University of Michigan Medical Center, Ann Arbor 48109-0028, USA
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