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Mahmoudi R, Novella JL, Laurent-Badr S, Boulahrouz S, Tran D, Morrone I, Jaïdi Y. Cholinergic Antagonists and Behavioral Disturbances in Neurodegenerative Diseases. Int J Mol Sci 2023; 24:ijms24086921. [PMID: 37108085 PMCID: PMC10138684 DOI: 10.3390/ijms24086921] [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: 02/14/2023] [Revised: 03/26/2023] [Accepted: 04/04/2023] [Indexed: 04/29/2023] Open
Abstract
Cholinergic antagonists interfere with synaptic transmission in the central nervous system and are involved in pathological processes in patients with neurocognitive disorders (NCD), such as behavioral and psychological symptoms of dementia (BPSD). In this commentary, we will briefly review the current knowledge on the impact of cholinergic burden on BPSD in persons with NCD, including the main pathophysiological mechanisms. Given the lack of clear consensus regarding symptomatic management of BPSD, special attention must be paid to this preventable, iatrogenic condition in patients with NCD, and de-prescription of cholinergic antagonists should be considered in patients with BPSD.
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Affiliation(s)
- Rachid Mahmoudi
- Department of Geriatric and Internal Medicine, Reims University Hospitals, Maison Blanche Hospital, 51092 Reims, France
- UR 3797 Vieillissement, Fragilité (VieFra), Faculty of Medicine, University of Reims Champagne-Ardenne, 51687 Reims, France
| | - Jean Luc Novella
- Department of Geriatric and Internal Medicine, Reims University Hospitals, Maison Blanche Hospital, 51092 Reims, France
- UR 3797 Vieillissement, Fragilité (VieFra), Faculty of Medicine, University of Reims Champagne-Ardenne, 51687 Reims, France
| | - Sarah Laurent-Badr
- Department of Geriatric and Internal Medicine, Reims University Hospitals, Maison Blanche Hospital, 51092 Reims, France
| | - Sarah Boulahrouz
- Department of Geriatric and Internal Medicine, Reims University Hospitals, Maison Blanche Hospital, 51092 Reims, France
- UR 3797 Vieillissement, Fragilité (VieFra), Faculty of Medicine, University of Reims Champagne-Ardenne, 51687 Reims, France
| | - David Tran
- Department of Geriatric and Internal Medicine, Reims University Hospitals, Maison Blanche Hospital, 51092 Reims, France
| | - Isabella Morrone
- Department of Geriatric and Internal Medicine, Reims University Hospitals, Maison Blanche Hospital, 51092 Reims, France
- Cognition Health and Society Laboratory (C2S-EA 6291), Faculty of Medicine, University of Reims Champagne-Ardenne, 51687 Reims, France
| | - Yacine Jaïdi
- Department of Geriatric and Internal Medicine, Reims University Hospitals, Maison Blanche Hospital, 51092 Reims, France
- UR 3797 Vieillissement, Fragilité (VieFra), Faculty of Medicine, University of Reims Champagne-Ardenne, 51687 Reims, France
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Reale M, Carrarini C, Russo M, Dono F, Ferri L, Pietro MD, Costantini E, Porreca A, Nicola MD, Onofrj M, Bonanni L. Muscarinic Receptors Expression in the Peripheral Blood Cells Differentiate Dementia with Lewy Bodies from Alzheimer's Disease. J Alzheimers Dis 2021; 85:323-330. [PMID: 34806612 DOI: 10.3233/jad-215285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Central nervous system disruption of cholinergic (ACh) signaling, which plays a major role in cognitive processes, is well documented in dementia with Lewy bodies (DLB) and Alzheimer's disease (AD). The expression of muscarinic ACh receptors type 1 and 4 (CHRM1 and CHRM4) has been reported to be altered in the brain of DLB patients. OBJECTIVE We aim to assess the peripheral gene expression of CHRM1 and 4 in DLB as a possible marker as compared to AD and healthy control (HC) subjects. METHODS Peripheral blood mononuclear cells were collected from 21 DLB, 13 AD, and 8 HC matched subjects. RT-PCR was performed to estimate gene expression of CHRM1 and CHRM4. RESULTS Peripheral CHRM1 expression was higher and CHRM4 was lower in DLB and AD compared to HC, whereas both CHRM1 and CHRM4 levels were higher in AD compared to DLB patients. Receiver operating characteristics curves, with logistic regression analysis, showed that combining peripheral CHRM1 and CHRM4 levels, DLB and AD subjects were classified with an accuracy of 76.0%. CONCLUSION Alterations of peripheral CHRM1 and CHRM4 was found in both AD and DLB patients as compared to HC. CHRM1 and CHRM4 gene expression resulted to be lower in DLB patients compared to AD. In the future, peripheral CHRM expression could be studied as a possible marker of neurodegenerative conditions associated with cholinergic deficit and a possible marker of response to acetylcholinesterase inhibitors.
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Affiliation(s)
- Marcella Reale
- Department of Innovative Technologies in Medicine and Dentistry, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Claudia Carrarini
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Mirella Russo
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Fedele Dono
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Laura Ferri
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Martina Di Pietro
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Erica Costantini
- Department of Medicine and Aging Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Annamaria Porreca
- Department of Medical, Oral and Biotechnological Sciences, "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Marta Di Nicola
- Department of Medical, Oral and Biotechnological Sciences, "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Marco Onofrj
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Laura Bonanni
- Department of Medicine and Aging Sciences, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
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Yu L, Zhang H, Niu X, Wu L, Zhang Y, Wang B. Fate of chlorpyrifos, omethoate, cypermethrin, and deltamethrin during wheat milling and Chinese steamed bread processing. Food Sci Nutr 2021; 9:2791-2800. [PMID: 34136147 PMCID: PMC8194911 DOI: 10.1002/fsn3.1523] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 06/01/2019] [Accepted: 06/04/2019] [Indexed: 11/09/2022] Open
Abstract
To investigate the fractioning of chlorpyrifos, omethoate, cypermethrin, and deltamethrin during wheat milling and the fate of four pesticides during Chinese steamed bread (CSB) processing, wheat samples, which were sprayed twice with chlorpyrifos, omethoate, cypermethrin, and deltamethrin at three levels of concentrations during the grain-filling stage, were milled, and wheat flour was processed to CSB. The residues of four pesticides in the milling products, kneaded dough, fermented dough, and CSB were determined with GC-MS/MS. The concentrations of chlorpyrifos, omethoate, cypermethrin, and deltamethrin in bran were 1.46-1.57, 1.85-2.13, 1.27-1.86, and 1.63-2.33 times higher than those in wheat, respectively, while the residues of the four pesticides in shorts decreased approximately 27.97% to 57.02% for chlorpyrifos, 6.22% to 44.77% for cypermethrin, and 13.13% to 61.15% for deltamethrin compared with the residues in wheat (p < .05); however, omethoate levels approximately doubled in the ten-fold treatment group in shorts compared with those in wheat (p < .05). The residues of the four pesticides in flour were significantly lower than those in wheat, ranging from 38.68% to 98.04%. Chlorpyrifos and omethoate levels showed a slight decrease during the kneading and fermentation process, and further decreases of 2.46%-29.51% for chlorpyrifos and 14.22%-71.11% for omethoate were found in CSB; however, most of the groups of cypermethrin and deltamethrin showed various degrees of increases in kneaded and fermented dough and steamed bread compared with flour. The mechanism of this increase is unknown and needs further research.
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Affiliation(s)
- Lili Yu
- Chinese Academy of Agricultural Sciences / Laboratory of Quality and Safety Risk Assessment for Cereal Products (Beijing)Institute of Crop SciencesMinistry of AgricultureBeijingChina
| | - Huijie Zhang
- Chinese Academy of Agricultural Sciences / Laboratory of Quality and Safety Risk Assessment for Cereal Products (Beijing)Institute of Crop SciencesMinistry of AgricultureBeijingChina
| | - Xinning Niu
- Chinese Academy of Agricultural Sciences / Laboratory of Quality and Safety Risk Assessment for Cereal Products (Beijing)Institute of Crop SciencesMinistry of AgricultureBeijingChina
| | - Li Wu
- Chinese Academy of Agricultural Sciences / Laboratory of Quality and Safety Risk Assessment for Cereal Products (Beijing)Institute of Crop SciencesMinistry of AgricultureBeijingChina
| | - Yan Zhang
- Chinese Academy of Agricultural Sciences / Laboratory of Quality and Safety Risk Assessment for Cereal Products (Beijing)Institute of Crop SciencesMinistry of AgricultureBeijingChina
| | - Bujun Wang
- Chinese Academy of Agricultural Sciences / Laboratory of Quality and Safety Risk Assessment for Cereal Products (Beijing)Institute of Crop SciencesMinistry of AgricultureBeijingChina
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Bakker C, Prins S, Liptrot J, Hart EP, Klaassen ES, Brown GA, Brown A, Congreve M, Weir M, Marshall FH, Stevens J, Cross DM, Tasker T, Nathan PJ, Groeneveld GJ. Safety, pharmacokinetics and pharmacodynamics of HTL0009936, a selective muscarinic M 1 -acetylcholine receptor agonist: A randomized cross-over trial. Br J Clin Pharmacol 2021; 87:4439-4449. [PMID: 33891333 PMCID: PMC8596821 DOI: 10.1111/bcp.14872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 03/10/2021] [Accepted: 03/16/2021] [Indexed: 12/01/2022] Open
Abstract
AIMS HTL0009936 is a selective M1 muscarinic receptor agonist in development for cognitive dysfunction in Alzheimer's disease. Safety, tolerability and pharmacokinetics and exploratory pharmacodynamic effects of HTL0009936 administered by continuous IV infusion at steady state were investigated in elderly subjects with below average cognitive functioning (BACF). METHODS Part A was a four-treatment open label sequential study in healthy elderly investigating 10-83 mg HTL0009936 (IV) and a 24 mg HTL0009936 single oral dose. Part B was a five-treatment randomized, double-blind, placebo and physostigmine controlled cross-over study with IV HTL0009936 in elderly subjects with BACF. Pharmacodynamic assessments were performed using neurocognitive and electrophysiological tests. RESULTS Pharmacokinetics of HTL0009936 showed dose-proportional increases in exposure with a mean half-life of 2.4 hours. HTL0009936 was well-tolerated with transient dose-related adverse events (AEs). Small increases in mean systolic blood pressure of 7.12 mmHg (95% CI [3.99-10.24]) and in diastolic of 5.32 mmHg (95% CI [3.18-7.47]) were noted at the highest dose in part B. Overall, there was suggestive, but no definitive, positive or negative pharmacodynamic effects. Statistically significant effects were observed on P300 with HTL0009936 and adaptive tracking with physostigmine. CONCLUSIONS HTL0009936 showed well-characterized pharmacokinetics and single doses were safe and generally well-tolerated in healthy elderly subjects. Due to physostigmine tolerability issues and subject burden, the study design was changed and some pharmacodynamic assessments (neurocognitive) were performed at suboptimal drug exposures. Therefore no clear conclusions can be made on pharmacodynamic effects of HTL0009936, although an effect on P300 is suggestive of central target engagement.
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Affiliation(s)
- Charlotte Bakker
- Centre for Human Drug Research, Leiden, The Netherlands.,Leiden University Medical Center, Leiden, The Netherlands
| | - Samantha Prins
- Centre for Human Drug Research, Leiden, The Netherlands.,Leiden University Medical Center, Leiden, The Netherlands
| | | | - Ellen P Hart
- Centre for Human Drug Research, Leiden, The Netherlands
| | | | | | | | | | | | - Fiona H Marshall
- Sosei Heptares, Cambridge, UK.,MSD Research Laboratories (Merck & Co), Kenilworth, New Jersey, USA
| | - Jasper Stevens
- Centre for Human Drug Research, Leiden, The Netherlands.,University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | | | | | - Pradeep J Nathan
- Sosei Heptares, Cambridge, UK.,Department of Psychiatry, University of Cambridge, Cambridge, UK.,School of Psychological Sciences, Monash University, Australia
| | - Geert Jan Groeneveld
- Centre for Human Drug Research, Leiden, The Netherlands.,Leiden University Medical Center, Leiden, The Netherlands
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5
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Colloby SJ, Nathan PJ, McKeith IG, Bakker G, O'Brien JT, Taylor JP. Cholinergic muscarinic M 1/M 4 receptor networks in dementia with Lewy bodies. Brain Commun 2020; 2:fcaa098. [PMID: 32954342 PMCID: PMC7475694 DOI: 10.1093/braincomms/fcaa098] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 06/16/2020] [Accepted: 06/19/2020] [Indexed: 12/13/2022] Open
Abstract
Cholinergic dysfunction is central in dementia with Lewy bodies, possibly contributing to the cognitive and psychiatric phenotypes of this condition. We investigated baseline muscarinic M1/M4 receptor spatial covariance patterns in dementia with Lewy bodies and their association with changes in cognition and neuropsychiatric symptoms after 12 weeks of treatment with the cholinesterase inhibitor donepezil. Thirty-eight participants (14 cholinesterase inhibitor naive patients, 24 healthy older individuals) underwent 123I-iodo-quinuclidinyl-benzilate (M1/M4 receptor assessment) and 99mTc-exametazime (perfusion) single-photon emission computed tomography scanning. We implemented voxel principal components analysis, producing a series of images representing patterns of inter-correlated voxels across individuals. Linear regression analyses derived specific M1/M4 and perfusion spatial covariance patterns associated with patients. A discreet M1/M4 pattern that distinguished patients from controls (W1,19.7 = 16.7, P = 0.001), showed relative decreased binding in right lateral temporal and insula, as well as relative preserved/increased binding in frontal, precuneus, lingual and cuneal regions, implicating nodes within attention and dorsal visual networks. We then derived from patients an M1/M4 pattern that correlated with a positive change in mini-mental state examination (r = 0.52, P = 0.05), showing relative preserved/increased uptake in prefrontal, temporal pole and anterior cingulate, elements of attention-related networks. We also generated from patients an M1/M4 pattern that correlated with a positive change in neuropsychiatric inventory score (r = 0.77, P = 0.002), revealing relative preserved/increased uptake within a bilateral temporal-precuneal-striatal system. Although in a small sample and therefore tentative, we posit that optimal response of donepezil on cognitive and neuropsychiatric signs in patients with dementia with Lewy bodies were associated with a maintenance of muscarinic M1/M4 receptor expression within attentional/executive and ventral visual network hubs, respectively.
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Affiliation(s)
- Sean J Colloby
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK
| | - Pradeep J Nathan
- Experimental Medicine, Neuroscience Therapeutic Area, Sosei Heptares, Steinmetz Building, Granta Park, Cambridge CB21 6DG, UK.,Department of Psychiatry, University of Cambridge, Cambridge CB2 0QC, UK
| | - Ian G McKeith
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK
| | - Geor Bakker
- Experimental Medicine, Neuroscience Therapeutic Area, Sosei Heptares, Steinmetz Building, Granta Park, Cambridge CB21 6DG, UK
| | - John T O'Brien
- Department of Psychiatry, University of Cambridge, Cambridge CB2 0QC, UK
| | - John-Paul Taylor
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK
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Deng X, Zhang Y, Rong J, Kumata K, Shao T, Wang G, Hatori A, Mori W, Yu Q, Hu K, Fujinaga M, Shao Y, Josephson L, Sun S, Zhang MR, Liang S. Synthesis and preliminary evaluation of 18F-labeled 1-(6,7-dimethyl-4-(methylamino)-1,3-dihydro-2H-pyrrolo[3,4-c]pyridin-2-yl)-2-(trans-2-(6-fluoropyridin-3-yl)cyclopropyl)ethan-1-one for imaging muscarinic acetylcholine receptor subtype 4. Tetrahedron Lett 2020. [DOI: 10.1016/j.tetlet.2020.152060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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7
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Mandai T, Sako Y, Kurimoto E, Shimizu Y, Nakamura M, Fushimi M, Maeda R, Miyamoto M, Kimura H. T-495, a novel low cooperative M 1 receptor positive allosteric modulator, improves memory deficits associated with cholinergic dysfunction and is characterized by low gastrointestinal side effect risk. Pharmacol Res Perspect 2020; 8:e00560. [PMID: 31990455 PMCID: PMC6986443 DOI: 10.1002/prp2.560] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 12/20/2019] [Indexed: 12/20/2022] Open
Abstract
M1 muscarinic acetylcholine receptor (M1 R) activation can be a new therapeutic approach for the treatment of cognitive deficits associated with cholinergic hypofunction. However, M1 R activation causes gastrointestinal (GI) side effects in animals. We previously found that an M1 R positive allosteric modulator (PAM) with lower cooperativity (α-value) has a limited impact on ileum contraction and can produce a wider margin between cognitive improvement and GI side effects. In fact, TAK-071, a novel M1 R PAM with low cooperativity (α-value of 199), improved scopolamine-induced cognitive deficits with a wider margin against GI side effects than a high cooperative M1 R PAM, T-662 (α-value of 1786), in rats. Here, we describe the pharmacological characteristics of a novel low cooperative M1 R PAM T-495 (α-value of 170), using the clinically tested higher cooperative M1 R PAM MK-7622 (α-value of 511) as a control. In rats, T-495 caused diarrhea at a 100-fold higher dose than that required for the improvement of scopolamine-induced memory deficits. Contrastingly, MK-7622 showed memory improvement and induction of diarrhea at an equal dose. Combination of T-495, but not of MK-7622, and donepezil at each sub-effective dose improved scopolamine-induced memory deficits. Additionally, in mice with reduced acetylcholine levels in the forebrain via overexpression of A53T α-synuclein (ie, a mouse model of dementia with Lewy bodies and Parkinson's disease with dementia), T-495, like donepezil, reversed the memory deficits in the contextual fear conditioning test and Y-maze task. Thus, low cooperative M1 R PAMs are promising agents for the treatment of memory deficits associated with cholinergic dysfunction.
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Affiliation(s)
- Takao Mandai
- Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Yuu Sako
- Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Emi Kurimoto
- Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Yuji Shimizu
- Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan.,Biomolecular Research Laboratories, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Minoru Nakamura
- Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Makoto Fushimi
- Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Ryouta Maeda
- Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Maki Miyamoto
- Drug Metabolism and Pharmacokinetics Research Laboratories, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Haruhide Kimura
- Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
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Effects of obesity induced by high-calorie diet and its treatment with exenatide on muscarinic acetylcholine receptors in rat hippocampus. Biochem Pharmacol 2019; 169:113630. [DOI: 10.1016/j.bcp.2019.113630] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 08/30/2019] [Indexed: 12/17/2022]
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Erskine D, Taylor JP, Bakker G, Brown AJH, Tasker T, Nathan PJ. Cholinergic muscarinic M 1 and M 4 receptors as therapeutic targets for cognitive, behavioural, and psychological symptoms in psychiatric and neurological disorders. Drug Discov Today 2019; 24:2307-2314. [PMID: 31499186 DOI: 10.1016/j.drudis.2019.08.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 08/08/2019] [Accepted: 08/28/2019] [Indexed: 12/13/2022]
Abstract
Cholinergic dysfunction is involved in a range of neurological and psychiatric disorders, including schizophrenia, dementia and Lewy body disease (LBD), leading to widespread use of cholinergic therapies. However, such drugs have focused on increasing the availability of acetylcholine (ACh) generally, with relatively little work done on the muscarinic system and specific muscarinic receptor subtypes. In this review, we provide an overview of the major cholinergic pathways and cholinergic muscarinic receptors in the human brain and evidence for their dysfunction in several neurological and psychiatric disorders. We discuss how the selectivity of cholinergic system dysfunction suggests that targeted cholinergic therapeutics to the muscarinic receptor subtypes will be vital in treating several disorders associated with cognitive dysfunction and behavioural and psychological symptoms.
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Affiliation(s)
- Daniel Erskine
- Institute of Neuroscience, Newcastle University, Newcastle, UK.
| | | | | | | | | | - Pradeep J Nathan
- Sosei Heptares, Cambridge, UK; Department of Psychiatry, University of Cambridge, Cambridge, UK; School of Psychological Sciences, Monash University, Melbourne, VIC, Australia.
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10
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Deng X, Hatori A, Chen Z, Kumata K, Shao T, Zhang X, Yamasaki T, Hu K, Yu Q, Ma L, Wang G, Wang L, Shao Y, Josephson L, Sun S, Zhang MR, Liang S. Synthesis and Preliminary Evaluation of 11 C-Labeled VU0467485/AZ13713945 and Its Analogues for Imaging Muscarinic Acetylcholine Receptor Subtype 4. ChemMedChem 2018; 14:303-309. [PMID: 30589226 DOI: 10.1002/cmdc.201800710] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Indexed: 12/16/2022]
Abstract
Muscarinic acetylcholine receptors (mAChRs) have five distinct subunits (M1 -M5 ) and are involved in the action of the neurotransmitter acetylcholine in the central and peripheral nervous system. Attributed to the promising clinical efficacy of xanomeline, an M1 /M4 -preferring agonist, in patients of schizophrenia and Alzheimer's disease, M1 - or M4 -selective mAChR modulators have been developed that target the topographically distinct allosteric sites. Herein we report the synthesis and preliminary evaluation of 11 C-labeled positron emission tomography (PET) ligands based on a validated M4 R positive allosteric modulator VU0467485 (AZ13713945) to facilitate drug discovery. [11 C]VU0467485 and two other ligands were prepared in high radiochemical yields (>30 %, decay-corrected) with high radiochemical purity (>99 %) and high molar activity (>74 GBq μmol-1 ). In vitro autoradiography studies indicated that these three ligands possess moderate-to-high in vitro specific binding to M4 R. Nevertheless, further physiochemical property optimization is necessary to overcome the challenges associated with limited brain permeability.
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Affiliation(s)
- Xiaoyun Deng
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA
| | - Akiko Hatori
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Zhen Chen
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA
| | - Katsushi Kumata
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Tuo Shao
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA
| | - Xiaofei Zhang
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA
| | - Tomoteru Yamasaki
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Kuan Hu
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Qingzhen Yu
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA
| | - Longle Ma
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA
| | - Gangqiang Wang
- Hubei Collaborative Innovation Centre for Non-power Nuclear Technology, College of Nuclear Technology & Chemistry and Biology, Hubei University of Science and Technology, Xianning, China
| | - Lu Wang
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA.,Department of Nuclear Medicine and PET/CT-MRI Center, the First Affiliated Hospital of Jinan University & Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, 510630, China
| | - Yihan Shao
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Lee Josephson
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA
| | - Shaofa Sun
- Hubei Collaborative Innovation Centre for Non-power Nuclear Technology, College of Nuclear Technology & Chemistry and Biology, Hubei University of Science and Technology, Xianning, China
| | - Ming-Rong Zhang
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Steven Liang
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA
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Abstract
Purpose of Review To review the current status of positron emission tomography (PET) molecular imaging research of levodopa-induced dyskinesias (LIDs) in Parkinson’s disease (PD). Recent Findings Recent PET studies have provided robust evidence that LIDs in PD are associated with elevated and fluctuating striatal dopamine synaptic levels, which is a consequence of the imbalance between dopaminergic and serotonergic terminals, with the latter playing a key role in mishandling presynaptic dopamine release. Long-term exposure to levodopa is no longer believed to solely induce LIDs, as studies have highlighted that PD patients who go on to develop LIDs exhibit elevated putaminal dopamine release before the initiation of levodopa treatment, suggesting the involvement of other mechanisms, including altered neuronal firing and abnormal levels of phosphodiesterase 10A. Summary Dopaminergic, serotonergic, glutamatergic, adenosinergic and opioid systems and phosphodiesterase 10A levels have been shown to be implicated in the development of LIDs in PD. However, no system may be considered sufficient on its own for the development of LIDs, and the mechanisms underlying LIDs in PD may have a multisystem origin. In line with this notion, future studies should use multimodal PET molecular imaging in the same individuals to shed further light on the different mechanisms underlying the development of LIDs in PD.
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Murphy B, Ibrahim JE, Bugeja L, Pilgrim J, Cicuttini F. The Use of Deceased Controls in Epidemiologic Research: A Systematic Review. Am J Epidemiol 2017; 186:367-384. [PMID: 28460057 DOI: 10.1093/aje/kwx052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 08/25/2016] [Indexed: 12/13/2022] Open
Abstract
Scholarly debate on the use of deceased controls in epidemiologic research continues. This systematic review examined published epidemiologic research using deceased persons as a control group. A systematic search of 5 major biomedical literature databases (MEDLINE, CINAHL, PsycINFO, Scopus, and EMBASE) was conducted, using variations of the search terms "deceased" and "controls" to identify relevant peer-reviewed journal articles. Information was sought on study design, rationale for using deceased controls, application of theoretical principles of control selection, and discussion of the use of deceased controls. The review identified 134 studies using deceased controls published in English between 1978 and 2015. Common health outcomes under investigation included cancer (n = 31; 23.1%), nervous system diseases (n = 26; 19.4%), and injury and other external causes (n = 22; 16.4%). The majority of studies used deceased controls for comparison with deceased cases (n = 95; 70.9%). Investigators rarely presented their rationale for control selection (n = 25/134; 18.7%); however, common reasons included comparability of information on exposures, lack of appropriate controls from other sources, and counteracting bias associated with living controls. Comparable accuracy was the most frequently observed principle of control selection (n = 92; 68.7%). This review highlights the breadth of research using deceased controls and indicates their appropriateness in studies using deceased cases.
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Ahmed T, Zahid S, Mahboob A, Farhat SM. Cholinergic System and Post-translational Modifications: An Insight on the Role in Alzheimer's Disease. Curr Neuropharmacol 2017; 15:480-494. [PMID: 27012953 PMCID: PMC5543671 DOI: 10.2174/1570159x14666160325121145] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 12/02/2015] [Accepted: 03/03/2016] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is the most common form of old age dementia. The formation of amyloid plaques (Aβ), neurofibrillary tangles and loss of basal forebrain cholinergic neurons are the hallmark events in the pathology of AD. LITERATURE REVIEW Cholinergic system is one of the most important neurotransmitter system involved in learning and memory which preferentially degenerates in the initial stages of AD. Activation of cholinergic receptors (muscarinic and nicotinic) activates multiple pathways which result in post translational modifications (PTMs) in multiple proteins which bring changes in nervous system. Cholinergic receptors-mediated PTMs "in-part" substantially affect the biosynthesis, proteolysis, degradation and expression of many proteins and in particular, amyloid precursor protein (APP). APP is subjected to several PTMs (proteolytic processing, glycosylation, sulfation, and phosphorylation) during its course of processing, resulting in Aβ deposition, leading to AD. Aβ also alters the PTMs of tau which is a microtubule associated protein. Therefore, post-translationally modified tau and Aβ collectively aggravate the neuronal loss that leads to cholinergic hypofunction. CONCLUSION Despite the accumulating evidences, the interaction between cholinergic neurotransmission and the physiological significance of PTM events remain speculative and still needs further exploration. This review focuses on the role of cholinergic system and discusses the significance of PTMs in pathological progression of AD and highlights some important future directions.
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Affiliation(s)
- Touqeer Ahmed
- Neurobiology Laboratory, Department of Healthcare Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Sector H-12, Islamabad, 44000, Pakistan
| | - Saadia Zahid
- Neurobiology Laboratory, Department of Healthcare Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Sector H-12, Islamabad, 44000, Pakistan
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Politis M, Pagano G, Niccolini F. Imaging in Parkinson's Disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2017; 132:233-274. [DOI: 10.1016/bs.irn.2017.02.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Guerram M, Zhang LY, Jiang ZZ. G-protein coupled receptors as therapeutic targets for neurodegenerative and cerebrovascular diseases. Neurochem Int 2016; 101:1-14. [PMID: 27620813 DOI: 10.1016/j.neuint.2016.09.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 09/01/2016] [Accepted: 09/06/2016] [Indexed: 12/24/2022]
Abstract
Neurodegenerative and cerebrovascular diseases are frequent in elderly populations and comprise primarily of dementia (mainly Alzheimer's disease) Parkinson's disease and stroke. These neurological disorders (NDs) occur as a result of neurodegenerative processes and represent one of the most frequent causes of death and disability worldwide with a significant clinical and socio-economic impact. Although NDs have been characterized for many years, the exact molecular mechanisms that govern these pathologies or why they target specific individuals and specific neuronal populations remain unclear. As research progresses, many similarities appear which relate these diseases to one another on a subcellular level. Discovering these similarities offers hope for therapeutic advances that could ameliorate the conditions of many diseases simultaneously. G-protein coupled receptors (GPCRs) are the most abundant receptor type in the central nervous system and are linked to complex downstream pathways, manipulation of which may have therapeutic application in many NDs. This review will highlight the potential use of neurotransmitter GPCRs as emerging therapeutic targets for neurodegenerative and cerebrovascular diseases.
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Affiliation(s)
- Mounia Guerram
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing 210009, China; Faculty of Exact Sciences and Nature and Life Sciences, Department of Biology, Larbi Ben M'hidi University, Oum El Bouaghi 04000, Algeria
| | - Lu-Yong Zhang
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing 210009, China; State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
| | - Zhen-Zhou Jiang
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing 210009, China; Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing 210009, China.
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16
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The distribution of muscarinic M1 receptors in the human hippocampus. J Chem Neuroanat 2016; 77:187-192. [PMID: 27435807 DOI: 10.1016/j.jchemneu.2016.07.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 07/13/2016] [Accepted: 07/15/2016] [Indexed: 11/21/2022]
Abstract
The muscarinic M1 receptor plays a significant role in cognition, probably by modulating information processing in key regions such as the hippocampus. To understand how the muscarinic M1 receptor achieves these functions in the hippocampus, it is critical to know the distribution of the receptor within this complex brain region. To date, there are limited data on the distribution of muscarinic M1 receptors in the human hippocampus which may also be confounded because some anti-muscarinic receptor antibodies have been shown to lack specificity. Initially, using Western blotting and immunohistochemistry, we showed the anti-muscarinic M1 receptor antibody to be used in our study bound to a single 62kDa protein that was absent in mice lacking the muscarinic M1 receptor gene. Then, using immunohistochemistry, we determined the distribution of muscarinic M1 receptors in human hippocampus from 10 subjects with no discernible history of a neurological or psychiatric disorder. Our data shows the muscarinic M1 receptor to be predominantly on pyramidal cells in the hippocampus. Muscarinic M1 receptor positive cells were most apparent in the deep polymorphic layer of the dentate gyrus, the pyramidal cell layer of cornu ammonis region 3, the cellular layers of the subiculum, layer II of the presubiculum and layer III and V of the parahippocampal gyrus. Positive cells were less numerous and less intensely stained in the pyramidal layer of cornu ammonis region 2 and were sparse in the molecular layer of the dentate gyrus as well as cornu ammonis region 1. Although immunoreactivity was present in the granular layer of the dentate gyrus, it was difficult to identity individual immunopositive cells, possibly due to the density of cells. This distribution of the muscarinic M1 receptors in human hippocampus, and its localisation on glutamatergic cells, would suggest the receptor has a significant role in modulating excitatory hippocampal neurotransmission.
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Roy R, Niccolini F, Pagano G, Politis M. Cholinergic imaging in dementia spectrum disorders. Eur J Nucl Med Mol Imaging 2016; 43:1376-86. [PMID: 26984612 PMCID: PMC4865532 DOI: 10.1007/s00259-016-3349-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 02/18/2016] [Indexed: 12/31/2022]
Abstract
The multifaceted nature of the pathology of dementia spectrum disorders has complicated their management and the development of effective treatments. This is despite the fact that they are far from uncommon, with Alzheimer's disease (AD) alone affecting 35 million people worldwide. The cholinergic system has been found to be crucially involved in cognitive function, with cholinergic dysfunction playing a pivotal role in the pathophysiology of dementia. The use of molecular imaging such as SPECT and PET for tagging targets within the cholinergic system has shown promise for elucidating key aspects of underlying pathology in dementia spectrum disorders, including AD or parkinsonian dementias. SPECT and PET studies using selective radioligands for cholinergic markers, such as [(11)C]MP4A and [(11)C]PMP PET for acetylcholinesterase (AChE), [(123)I]5IA SPECT for the α4β2 nicotinic acetylcholine receptor and [(123)I]IBVM SPECT for the vesicular acetylcholine transporter, have been developed in an attempt to clarify those aspects of the diseases that remain unclear. This has led to a variety of findings, such as cortical AChE being significantly reduced in Parkinson's disease (PD), PD with dementia (PDD) and AD, as well as correlating with certain aspects of cognitive function such as attention and working memory. Thalamic AChE is significantly reduced in progressive supranuclear palsy (PSP) and multiple system atrophy, whilst it is not affected in PD. Some of these findings have brought about suggestions for the improvement of clinical practice, such as the use of a thalamic/cortical AChE ratio to differentiate between PD and PSP, two diseases that could overlap in terms of initial clinical presentation. Here, we review the findings from molecular imaging studies that have investigated the role of the cholinergic system in dementia spectrum disorders.
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Affiliation(s)
- Roman Roy
- Neurodegeneration Imaging Group, Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Flavia Niccolini
- Neurodegeneration Imaging Group, Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Gennaro Pagano
- Neurodegeneration Imaging Group, Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Marios Politis
- Neurodegeneration Imaging Group, Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
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Kitajima Y, Hori K, Konishi K, Tani M, Tomioka H, Akashi N, Hosoi M, Inamoto A, Hasegawa S, Kikuchi N, Takahashi A, Hachisu M. A Review of the Role of Anticholinergic Activity in Lewy Body Disease and Delirium. NEURODEGENER DIS 2015; 15:162-7. [PMID: 26138494 DOI: 10.1159/000381522] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We have previously proposed a hypothesis in which we argue that anticholinergic activity (AA) appears endogenously in Alzheimer's disease (AD). Acetylcholine (ACh) controls both cognitive function and inflammation. Consequently, when the downregulation of ACh reaches critical levels, the inflammatory system is upregulated and proinflammatory cytokines with AA appear. However, factors other than downregulation of ACh can produce AA; even if ACh downregulation does not reach critical levels, AA can still appear if one of these other AA-producing factors is added. These factors can include neurocognitive disorders other than AD, such as delirium and Lewy body disease (LBD). In delirium, ACh downregulation fails to reach critical levels, but AA appears due to the use of medicines, physical illnesses or mental stress (termed 'AA inserts'). In LBD, we speculate that AA appears endogenously, even in the absence of severe cognitive dysfunction, for 2 reasons. One reason is that patterns of ACh deterioration are different in LBD from those in AD, with synergistic actions between amyloid and α-synuclein thought to cause additional or severe symptoms that accelerate the disease course. The second reason is that AA occurs through disinhibition by reduced cortisol levels that result from severe autonomic parasympathetic dysfunction in LBD.
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Affiliation(s)
- Yuka Kitajima
- Department of Anesthesiology, School of Medicine, Juntendo University, Tokyo, Japan
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Colloby SJ, McKeith IG, Wyper DJ, O'Brien JT, Taylor JP. Regional covariance of muscarinic acetylcholine receptors in Alzheimer's disease using (R, R) [(123)I]-QNB SPECT. J Neurol 2015; 262:2144-53. [PMID: 26122542 DOI: 10.1007/s00415-015-7827-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 06/11/2015] [Accepted: 06/13/2015] [Indexed: 10/23/2022]
Abstract
Alzheimer's disease (AD) is characterised by deficits in cholinergic neurotransmission and subsequent receptor changes. We investigated (123)I-iodo-quinuclidinyl-benzilate (QNB) SPECT images using spatial covariance analysis (SCA), to detect an M1/M4 receptor spatial covariance pattern (SCP) that distinguished AD from controls. Furthermore, a corresponding regional cerebral blood flow (rCBF) SCP was also derived. Thirty-nine subjects (15 AD and 24 healthy elderly controls) underwent (123)I-QNB and (99m)Tc-exametazime SPECT. Voxel SCA was simultaneously applied to the set of smoothed/registered scans, generating a series of eigenimages representing common intercorrelated voxels across subjects. Linear regression identified individual M1/M4 and rCBF SCPs that discriminated AD from controls. The M1/M4 SCP showed concomitant decreased uptake in medial temporal, inferior frontal, basal forebrain and cingulate relative to concomitant increased uptake in frontal poles, occipital, pre-post central and precuneus/superior parietal regions (F1,37 = 85.7, p < 0.001). A largely different perfusion SCP was obtained showing concomitant decreased rCBF in medial and superior temporal, precuneus, inferior parietal and cingulate relative to concomitant increased rCBF in cerebellum, pre-post central, putamen, fusiform and brain stem/midbrain regions (F1,37 = 77.5, p < 0.001). The M1/M4 SCP expression correlated with the duration of cognitive symptoms (r = 0.90, p < 0.001), whereas the rCBF SCP expression negatively correlated with MMSE, CAMCOG and CAMCOGmemory (r ≥ |0.63|, p ≤ 0.006). (123)I-QNB SPECT revealed an M1/M4 basocortical covariance pattern, distinct from rCBF, reflecting the duration of disease rather than current clinical symptoms. This approach could be more sensitive than univariate methods in characterising the cholinergic/rCBF changes that underpin the clinical phenotype of AD.
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Affiliation(s)
- Sean J Colloby
- Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, NE4 5PL, UK.
| | - Ian G McKeith
- Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, NE4 5PL, UK
| | - David J Wyper
- SINAPSE, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, G12 8QB, UK
| | - John T O'Brien
- Department of Psychiatry, University of Cambridge, Level E4, Box 189, Cambridge, CB2 0QC, UK
| | - John-Paul Taylor
- Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, NE4 5PL, UK
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20
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Takahashi T, Ohnishi H, Sugiura Y, Honda K, Suematsu M, Kawasaki T, Deguchi T, Fujii T, Orihashi K, Hippo Y, Watanabe T, Yamagaki T, Yuba S. Non‐neuronal acetylcholine as an endogenous regulator of proliferation and differentiation of Lgr5‐positive stem cells in mice. FEBS J 2014; 281:4672-90. [DOI: 10.1111/febs.12974] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 07/22/2014] [Accepted: 08/14/2014] [Indexed: 12/13/2022]
Affiliation(s)
- Toshio Takahashi
- Suntory Foundation for Life Sciences Bioorganic Research Institute Osaka Japan
| | - Hiroe Ohnishi
- National Institute of Advanced Industrial Science and Technology Hyogo Japan
| | - Yuki Sugiura
- Department of Biochemistry School of Medicine Keio University Tokyo Japan
- Precursory Research for Embryonic Science and Technology Tokyo Japan
| | - Kurara Honda
- Department of Biochemistry School of Medicine Keio University Tokyo Japan
- Precursory Research for Embryonic Science and Technology Tokyo Japan
| | - Makoto Suematsu
- Department of Biochemistry School of Medicine Keio University Tokyo Japan
- Japan Science Technology Agency Exploratory Research for Advanced Technology Suematsu Gas Biology Project Tokyo Japan
| | - Takashi Kawasaki
- National Institute of Advanced Industrial Science and Technology Hyogo Japan
| | - Tomonori Deguchi
- National Institute of Advanced Industrial Science and Technology Hyogo Japan
| | - Takeshi Fujii
- Department of Pharmacology Faculty of Pharmaceutical Sciences Doshisha Women's College of Liberal Arts Kyoto Japan
| | - Kaoru Orihashi
- Division of Cancer Development System National Cancer Research Institute Tokyo Japan
| | - Yoshitaka Hippo
- Division of Cancer Development System National Cancer Research Institute Tokyo Japan
| | - Takehiro Watanabe
- Suntory Foundation for Life Sciences Bioorganic Research Institute Osaka Japan
| | - Tohru Yamagaki
- Suntory Foundation for Life Sciences Bioorganic Research Institute Osaka Japan
| | - Shunsuke Yuba
- National Institute of Advanced Industrial Science and Technology Hyogo Japan
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21
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Ballard C, Aarsland D, Francis P, Corbett A. Neuropsychiatric symptoms in patients with dementias associated with cortical Lewy bodies: pathophysiology, clinical features, and pharmacological management. Drugs Aging 2013; 30:603-11. [PMID: 23681401 DOI: 10.1007/s40266-013-0092-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD) are synucleinopathies that lead to neurodegeneration and dementia. Although they result in symptoms common to Alzheimer's disease, they are associated with early emergence of parkinsonism and high frequency of neuropsychiatric symptoms, most commonly hallucinations and delusions. This review summarizes the current understanding of the underlying biology of neuropsychiatric symptoms in DLB and PDD and the evidence base for treatment to address them. Disruption to cholinergic and serotonergic neurotransmission and synapse activity are highlighted as primary pathological factors in neuropsychiatric symptoms, particularly loss of key neurotransmitter functions, alterations to neuronal receptors in the serotonergic pathway, and regionally specific structural changes that are linked to specific symptoms. Review of options for pharmacological treatment of neuropsychiatric symptoms suggests that the best evidence for the value of treatment is for cholinesterase inhibitors, with an indication that people with visual hallucinations are particularly likely to benefit. Evidence for the benefits of antipsychotics other than clozapine is limited, and there are serious safety concerns about the use of antipsychotics in these patients. Evidence to support other pharmacological interventions is very preliminary. Nonpharmacological approaches based on person-centered care and cholinesterase inhibitors should be considered as the first-line treatment for neuropsychiatric symptoms except in extreme cases.
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Affiliation(s)
- Clive Ballard
- Wolfson Centre for Age-Related Diseases, King's College London, Wolfson Building, Guy's Campus, London, SE1 1UL, UK.
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22
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Jellinger KA. Neurobiology of cognitive impairment in Parkinson’s disease. Expert Rev Neurother 2012; 12:1451-1466. [DOI: 10.1586/ern.12.131] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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23
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Burghaus L, Eggers C, Timmermann L, Fink GR, Diederich NJ. Hallucinations in neurodegenerative diseases. CNS Neurosci Ther 2012; 18:149-59. [PMID: 21592320 DOI: 10.1111/j.1755-5949.2011.00247.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Patients with neurodegenerative disease frequently experience hallucinations and illusionary perceptions. As early symptoms, hallucinations may even have diagnostic relevance (i.e., for the diagnosis of Lewy Body Dementia). In the later course of the disease, hallucinations may appear as characteristic symptoms and often constitute a particular challenge for therapeutic endeavors. Here, the distinction of disease-inherent hallucinations from medication-associated perceptual disturbances is particularly relevant. Synucleinopathies and tauopathies have different risk profiles for hallucinations. In synucleinopathies hallucinations are much more frequent and phenomenology is characterized by visual, short-lived hallucinations, with insight preserved for a long time. A “double hit” theory proposes that dysfunctionality of both associative visual areas and changes of limbic areas or the ventral striatum are required. In contrast, in tauopathies the hallucinations are more rare and mostly embedded in confusional states with agitation and with poorly defined or rapidly changing paranoia. The occurrence of hallucinations has even been proposed as an exclusion criterion for tauopathies with Parkinsonian features such as progressive supranuclear palsy. To date, treatment remains largely empirical, except the use of clozapine and cholinesterase inhibitors in synucleinopathies, which is evidence-based. The risk of increased neuroleptic sensitivity further restricts the treatment options in patients with Lewy Body Dementia. Coping Strategies and improvement of visual acuity and sleep quality may be useful therapeutic complements.
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Affiliation(s)
- Lothar Burghaus
- Department of Neurology, University of Cologne, Cologne, Germany.
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Scarr E. Muscarinic receptors: their roles in disorders of the central nervous system and potential as therapeutic targets. CNS Neurosci Ther 2011; 18:369-79. [PMID: 22070219 DOI: 10.1111/j.1755-5949.2011.00249.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Phylogenetically, acetylcholine is an ancient neurochemical. Therefore, it is not surprising that cholinergic neurons project extensively throughout the central nervous system, innervating a wide range of structures within the brain. In fact, acetylcholine is involved in processes that underpin some of our most basic central functions. Both muscarinic and nicotinic receptor families, which mediate cholinergic transmission, have been implicated in the pathophysiology of psychiatric and neurological disorders. The question that remains to be definitively answered is whether or not these receptors are viable targets for the development of future therapeutic agents.
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Affiliation(s)
- Elizabeth Scarr
- Department of Psychiatry, University of Melbourne, Victoria, Australia.
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25
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Cardoso CC, Ricardo VP, Frussa-Filho R, Porto CS, Abdalla FMF. Effects of 17β-estradiol on expression of muscarinic acetylcholine receptor subtypes and estrogen receptor α in rat hippocampus. Eur J Pharmacol 2010; 634:192-200. [DOI: 10.1016/j.ejphar.2010.02.032] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 02/01/2010] [Accepted: 02/15/2010] [Indexed: 12/01/2022]
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Cortical M1 receptor concentration increases without a concomitant change in function in Alzheimer's disease. J Chem Neuroanat 2010; 40:63-70. [PMID: 20347961 DOI: 10.1016/j.jchemneu.2010.03.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 03/17/2010] [Accepted: 03/17/2010] [Indexed: 01/08/2023]
Abstract
Although the M(1) muscarinic receptor is a potential therapeutic target for Alzheimer's disease (AD) based on its wide spread distribution in brain and its association with learning and memory processes, whether its receptor response is altered during the onset of AD remains unclear. A novel [(35)S]GTPgammaS binding/immunocapture assay was employed to evaluated changes in M(1) receptor function in cortical tissue samples harvested from people who had no cognitive impairment (NCI), mild cognitive impairment (MCI), or AD. M(1) function was stable across clinical groups. However, [(3)H]-oxotremorine-M radioligand binding studies revealed that the concentration of M(1) cortical receptors increased significantly between the NCI and AD groups. Although M(1) receptor function did not correlate with cognitive function based upon mini-mental status examination (MMSE) or global cognitive score (GCS), functional activity was negatively correlated with the severity of neuropathology determined by Braak staging and NIA-Reagan criteria for AD. Since M(1) agonists have the potential to modify the pathologic hallmarks of AD, as well as deficits in cognitive function in animal models of this disease, the present findings provide additional support for targeting the M(1) receptor as a potential therapeutic for AD.
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Localisation of pre- and postsynaptic cholinergic markers in the human brain. Behav Brain Res 2010; 221:341-55. [PMID: 20170687 DOI: 10.1016/j.bbr.2010.02.025] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Accepted: 02/10/2010] [Indexed: 12/20/2022]
Abstract
The cholinergic neurotransmission in the central nervous system plays an important role in modulating cognitive processes such as learning, memory, arousal and sleep as well as in modulating locomotor activity. Dysfunction of the central cholinergic system is involved in numerous neuropsychiatric diseases. This review will provide a synopsis on the regional localisation of cholinergic and cholinoceptive structures within the adult human brain. On the cholinergic site data based on the distribution of choline acetyltransferase-immunoreactive structures are in the focus, complemented by data from acetylcholinesterase and vesicular acetylcholine transporter studies. On the cholinoceptive site, the distribution and localisation of receptors that transduce the acetylcholine message, i.e. the muscarinic and the nicotinic acetylcholine receptors is summarized. In addition to these data obtained on post mortem brain an overview of markers which allow for the in vivo monitoring of the cholinergic system in the brain is given. The detailed knowledge on the distribution and localisation of cholinergic markers in human brain will provide further information on the cholinergic circuits of neurotransmission - a prerequisite for the interpretation of in vivo imaging data and the development of selective diagnostic and therapeutic compounds.
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Francis PT. Biochemical and pathological correlates of cognitive and behavioural change in DLB/PDD. J Neurol 2009; 256 Suppl 3:280-5. [PMID: 19711117 DOI: 10.1007/s00415-009-5247-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD) are second only to Alzheimer's disease (AD) in frequency. In particular it is evident that up to 80% of people with PD will develop dementia towards the end of their life. While the neurobiology of movement disorder has been well studied in PD, much less attention has been given to mechanisms underlying the cognitive and behavioural symptoms associated with DLB and PDD. To date, the best correlate of cognitive impairment appears to be cortical Lewy bodies; however, new emphasis has been placed on small aggregates of synuclein. Furthermore, very few studies have attempted to investigate the neurochemical correlates of behavioural disorders in DLB/PDD and whether these are similar or distinct from AD. Aggregated alpha-synuclein forms the core component of Lewy bodies, a major pathological feature of Parkinson's-related conditions. The 26S proteasome is an ATP-dependent protease that catalyses the breakdown of alpha-synuclein. Previous studies have implicated alterations in the proteasome in PD. Furthermore, proteasome inhibitors have been reported to induce alpha-synuclein aggregation and Lewy body-like inclusions, resulting in neuronal loss both in vitro and in vivo. Our preliminary results indicate that selective alterations in the expression of proteosome sub-units are a feature of both DLB and PDD, while changes in activity are restricted to PDD. Depression is a common symptom in DLB/PDD, yet the evidence base for standard treatment with SSRIs is limited. In contrast to previous studies of AD, our results indicate that there is no association between depression and the 5-HT transporter, while there was a significant increase in the number of 5-HT1A receptors in those DLB/PDD patients with depression. These data may provide an insight into the lack of success of current treatments and suggest alternative approaches.
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Affiliation(s)
- Paul T Francis
- King's College London, Wolfson Centre for Age-Related Diseases, Guy's Campus, St Thomas Street, London, SE1 1UL, UK.
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Warren NM, Piggott MA, Lees AJ, Perry EK, Burn DJ. Intact coupling of M1 receptors and preserved M2 and M4 receptors in the cortex in progressive supranuclear palsy: Contrast with other dementias. J Chem Neuroanat 2008; 35:268-74. [DOI: 10.1016/j.jchemneu.2008.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2007] [Revised: 01/08/2008] [Accepted: 01/08/2008] [Indexed: 12/16/2022]
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Abstract
Dementia with Lewy Bodies (DLB) is the second most common form of dementia in the elderly. Core features of the DLB are fluctuating cognitive symptoms, visual hallucinations and spontaneous parkinsonism. The clinical diagnostic criteria are very useful in the differentiation between DLB and Alzheimer's disease. The deficits in cholinergic neurotransmission are pronounced and associated with cognitive and psychotic symptoms. An 83 years old patient with DLB showed well formed recurrent visual hallucinations and fluctuating cognition and attention. There was no response to treatment with atypical neuroleptics. The patient responded within few days to treatment with Donepezil. Both cognitive and behavioural symptoms were improved significantly.
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Affiliation(s)
- M Omerovic
- Klinik und Poliklinik für Psychiatrie und Psychotherapie der Ludwig-Maximilians-Universität München, Nussbaumstrasse 7, 80336, München
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Pakrasi S, Colloby SJ, Firbank MJ, Perry EK, Wyper DJ, Owens J, McKeith IG, Williams ED, O'Brien JT. Muscarinic acetylcholine receptor status in Alzheimer’s disease assessed using (R, R) 123I-QNB SPECT. J Neurol 2007; 254:907-13. [PMID: 17361343 DOI: 10.1007/s00415-006-0473-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2006] [Revised: 09/14/2006] [Accepted: 10/03/2006] [Indexed: 10/23/2022]
Abstract
BACKGROUND One of the most characteristic changes in Alzheimer's disease (AD) is a deficit in cortical cholinergic neurotransmission and associated receptor changes. OBJECTIVE To investigate differences in the distribution of M1/M4 receptors using (R, R) (123)I-iodo-quinuclidinyl-benzilate (QNB) and single photon emission computed tomography (SPECT) in patients with mild/moderate AD and age-matched controls. Also, to compare (123)I-QNB uptake to the corresponding changes in regional cerebral blood flow (rCBF) in the same subjects. METHODS Forty two subjects (18 AD and 24 healthy elderly controls) underwent (123)IQNB and perfusion (99m)Tc-exametazime SPECT scanning. Image analysis was performed using statistical parametric mapping (SPM99) following intensity normalisation of each image to its corresponding mean whole brain uptake. Group differences and correlations were assessed using two sample t-tests and linear regression respectively. RESULTS Significant reductions in (123)I-QNB uptake were observed in regions of the frontal rectal gyrus, right parahippocampal gyrus, left hippocampus and areas of the left temporal lobe in AD compared to controls (height threshold of p < or = 0.001 uncorrected). Such regions were also associated with marked deficits in rCBF. No significant correlations were identified between imaging data and clinical variables. CONCLUSION Functional impairment as measured by rCBF is more widespread than changes in M1/M4 receptor density in mild/moderate AD, where there was little or no selective loss of M1/M4 receptors in these patients that was greater than the general functional deficits shown on rCBF scans.
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Affiliation(s)
- Sanjeet Pakrasi
- Institute for Ageing and Health, Newcastle University, Wolfson Research Centre, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne, NE4 6BE, UK
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Francis PT, Perry EK. Cholinergic and other neurotransmitter mechanisms in Parkinson's disease, Parkinson's disease dementia, and dementia with Lewy bodies. Mov Disord 2007; 22 Suppl 17:S351-7. [DOI: 10.1002/mds.21683] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Nardone R, Bratti A, Tezzon F. Motor cortex inhibitory circuits in dementia with Lewy bodies and in Alzheimer's disease. J Neural Transm (Vienna) 2006; 113:1679-84. [PMID: 17024328 DOI: 10.1007/s00702-006-0551-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2006] [Accepted: 08/27/2006] [Indexed: 11/24/2022]
Abstract
To determine whether a peculiar neurophysiological profile may contribute to characterize dementia with Lewy bodies (DLB) vs. Alzheimer disease (AD), we used transcranial magnetic stimulation to examine the excitability of two different inhibitory systems of the motor cortex, short latency intracortical inhibition (SICI) and short latency afferent inhibition (SAI) in 10 patients with DLB, in 13 patients with AD and in 15 healthy subjects. SICI and SAI were significantly reduced in AD patients, while both were not significantly different from the controls in DLB patients. The differential pattern of SICI and SAI exhibited by AD vs. DLB may have diagnostic significance in discriminating DLB from AD. Furthermore, this technique may help to clarify the pathophysiological entity of DLB; since SAI is a cortical phenomenon that depends on central cholinergic activity, our findings suggest that the mechanisms of cholinergic depletion in DLB may be different from that in AD, while normal SICI may reflect a less pronounced dysregulation of the intracortical GABAergic inhibitory circuitries in DLB.
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Affiliation(s)
- R Nardone
- Department of Neurology, F. Tappeiner Hospital, Meran/o, Italy.
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34
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Colloby SJ, Pakrasi S, Firbank MJ, Perry EK, Piggott MA, Owens J, Wyper DJ, McKeith IG, Burn DJ, Williams ED, O'Brien JT. In vivo SPECT imaging of muscarinic acetylcholine receptors using (R,R) 123I-QNB in dementia with Lewy bodies and Parkinson's disease dementia. Neuroimage 2006; 33:423-9. [PMID: 16959499 DOI: 10.1016/j.neuroimage.2006.07.026] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 06/22/2006] [Accepted: 07/11/2006] [Indexed: 10/24/2022] Open
Abstract
INTRODUCTION Alterations in cholinergic function have been reported to be associated with dementia. The aim of this study was to investigate differences in the distribution of muscarinic acetylcholine receptors (mAChRs) using (R,R) 123I-iodo-quinuclidinyl-benzilate (QNB) and single photon emission computed tomography (SPECT) in dementia with Lewy bodies (DLB), Parkinson's disease dementia (PDD) and age-matched controls. 123I-QNB binding was also compared to the corresponding cerebral perfusion changes in the same subjects. METHODS 63 subjects (24 controls, 14 DLB, 25 PDD) underwent 123I-QNB and perfusion 99mTc-exametazine SPECT scanning. Image analysis, using statistical parametric mapping (SPM99), involved spatial normalisation of each image to a customised template, followed by smoothing and intensity normalisation of each image to its corresponding mean whole brain uptake. Group effects and correlations were assessed using two sample t tests and linear regression respectively. RESULTS Relative to controls, significant elevation of 123I-QNB binding was apparent in the right occipital lobe in DLB and right and left occipital lobes in PDD (height threshold p<or=0.001 uncorrected). PDD also showed significant loss in uptake in frontal regions and temporal lobes bilaterally that was not present in DLB. These patterns appeared to be independent of any corresponding rCBF changes. CONCLUSION Significant elevation of mAChRs in the occipital lobe was associated with DLB and PDD. This may relate to the visual disturbances that are prevalent in these disorders. Further studies are required in order to establish the role of mAChRs in visual function.
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Affiliation(s)
- Sean J Colloby
- Institute for Ageing and Health, Newcastle University, Wolfson Research Centre, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne NE4 6BE, UK.
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Kai T, Asai Y, Sakuma K, Koeda T, Nakashima K. Quantitative electroencephalogram analysis in dementia with Lewy bodies and Alzheimer's disease. J Neurol Sci 2005; 237:89-95. [PMID: 16019033 DOI: 10.1016/j.jns.2005.05.017] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2005] [Accepted: 05/28/2005] [Indexed: 11/18/2022]
Abstract
Clinicopathophysiological differences between dementia with Lewy bodies (DLB) and Alzheimer's disease (AD) remain obscure. Our goals were to determine whether characteristic findings of electroencephalogram (EEG) power and coherence in DLB and a differential pathophysiological mechanism of quantitative EEG existed between DLB and AD. The group consisted of 15 patients with AD or DLB and 12 age-matched controls. Original EEG signals were recorded from 14 scalp electrodes positioned according to the International 10-20 System, using digitally linked earlobes as a reference. Although EEG power spectral analysis showed increasing EEG power density in patients with DLB in the delta and theta bands, such a difference did not exist in patients with AD. Compared with AD, the delta and theta band intrahemispheric coherence values in the fronto-temporo-central regions were higher in DLB. In the beta band, AD was lower than DLB in almost all temporo-centro-parieto-occipital regions. Comparing the mean power value between patients with/without donepezil treatment, there was a significantly lower EEG power density in the delta and theta bands in DLB subjects taking donepezil than in subjects not taking donepezil, whereas there was no significant difference in AD patients. These results suggest that cholinergic dysfunction is stronger in DLB than AD.
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Affiliation(s)
- Toru Kai
- Division of Neurology, Institute of Neurological Sciences, Faculty of Medicine, Tottori University, 36-1 Nishimachi, Yonago 683-8504, Japan
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Liu HC, Hong CJ, Liu TY, Chi CW, Tsai SJ. Association analysis for the muscarinic M1 receptor genetic polymorphisms and Alzheimer's disease. Dement Geriatr Cogn Disord 2005; 19:42-5. [PMID: 15383745 DOI: 10.1159/000080970] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/03/2004] [Indexed: 11/19/2022] Open
Abstract
In the ongoing search to reveal the pathophysiology of Alzheimer's disease (AD), the cholinergic system is important due to its role in cognitive function and its significance with respect to the results of postmortem pathology and animal model studies. For this investigation, we tested the hypothesis that the allelic variant (C267A) of the cholinergic receptor muscarinic 1 (CHRM1) confers susceptibility to AD or is related to its age of onset, in a sample population of 232 AD patients and 169 normal controls. The distribution of the CHRM1 genotypes (p = 0.919) and alleles (p = 0.327) did not differ significantly comparing AD patients and controls, even after stratification according to apolipoprotein E genotype. The onset age was not significantly different comparing the CHRM1 genotype groups. Our negative findings suggest that it is unlikely that the CHRM1 C267A polymorphism plays a substantial role in conferring susceptibility to AD. We propose that other genetic variations of CHRM1, relating either to AD or to the therapeutic response for AD, may need further investigation.
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Affiliation(s)
- Hsiu-Chih Liu
- Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
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37
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Teaktong T, Piggott MA, Mckeith IG, Perry RH, Ballard CG, Perry EK. Muscarinic M2 and M4 receptors in anterior cingulate cortex: relation to neuropsychiatric symptoms in dementia with Lewy bodies. Behav Brain Res 2005; 161:299-305. [PMID: 15922057 DOI: 10.1016/j.bbr.2005.02.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2005] [Accepted: 02/18/2005] [Indexed: 10/25/2022]
Abstract
Alterations in cholinergic functions have been reported to be associated with neuropsychiatric symptoms in dementia. Increased M1 muscarinic receptor binding in temporal cortex is associated with delusions in dementia with Lewy bodies (DLB) patients and increased M2/M4 receptor binding with psychosis in Alzheimer's disease. However, the relation between M2 and M4 muscarinic receptor and psychotic symptoms in DLB is unknown. The aim of this study was to measure M2 and M4 receptors in the anterior cingulate cortex in DLB and to correlate the neurochemical findings with neuropsychiatric symptoms. Muscarinic M2 and M4 receptor levels in the anterior cingulate cortex and adjacent cortex (Brodmann's area [BA] 32) were measured separately by using a radioligand binding protocol based on binding of [(3)H]AF-DX 384 in the presence and absence of dicyclomine, a potent M4 receptor antagonist. M2 receptor binding was significantly increased, while M4 receptor binding was unchanged in the cingulate cortex and BA32 of DLB patients compared with age-matched controls. Impaired consciousness was significantly associated with increased M4 binding and delusions were significantly associated with increased M2 binding. Increased M2 and M4 receptor binding in DLB was also associated with visual hallucinations. Upregulation of M2 and M4 muscarinic receptors in cingulate and adjacent cortex may thus contribute to the development of psychosis in DLB, with potential implications for treatments with drugs acting on these receptors.
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Affiliation(s)
- Thanasak Teaktong
- Institute for Ageing and Health, MRC Building, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne NE46BE, UK
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Shiozaki K, Iseki E. Decrease in GTP-sensitive high affinity agonist binding of muscarinic acetylcholine receptors in autopsied brains of dementia with Lewy bodies and Alzheimer's disease. J Neurol Sci 2004; 223:145-8. [PMID: 15337615 DOI: 10.1016/j.jns.2004.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2004] [Revised: 05/05/2004] [Accepted: 05/06/2004] [Indexed: 11/20/2022]
Abstract
To determine changes in signal transduction from the muscarinic acetylcholine receptor (mAChR) to G protein in brain tissue of dementia with Lewy bodies (DLB) and Alzheimer's disease (AD), we investigated GTP-sensitive agonist high affinity binding, which is considered an index of the formation of the mAChR-G protein complex. Brain tissue was obtained at necropsy from eight patients with DLB, nine patients with Alzheimer's disease and seven patients as controls. Membrane fractions were prepared from frontal and temporal cerebral tissues. Displacement curves of [(3)H]l-quinuclidinyl benzilate (QNB) binding by carbamylcholine were analyzed by the nonlinear least-squares methods. The proportion of and affinity for the agonist in GTP-sensitive agonist high affinity binding were estimated. The percentages GTP-sensitive agonist high affinity bindings were significantly decreased in DLB (P<0.01) and Alzheimer's disease (P<0.05) only in the frontal lobe. There were no significant differences in the temporal lobe. The ratio of agonist affinity (Kd value of low affinity component/Kd value of high affinity component) did not significantly differ among groups in either the frontal lobe or temporal lobe. The concentration of mAChR-G protein complex is considered reduced in the frontal lobe of brains with DLB and Alzheimer's disease. Therefore, signal transduction from mAChR to G protein was disturbed in the frontal lobe in these diseases.
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Affiliation(s)
- Kazumasa Shiozaki
- Department of Psychiatry, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa, Yokohama 236-0004, Japan.
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39
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Español AJ, de la Torre E, Sales ME. Parasympathetic modulation of local acute inflammation in murine submandibular glands. Inflammation 2003; 27:97-105. [PMID: 12797549 DOI: 10.1023/a:1023230717435] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The parasympathetic nervous system controls submandibular glands (SMG) functions in physiological and pathological conditions via muscarinic acetylcholine receptors (mAchR). We had previously demonstrated that IFNgamma and carbachol stimulate amylase secretion in normal murine SMG by mAchR activation. While the cytokine action depended on nitric oxide synthase activation, the effect of the agonist was mediated by prostaglandin E2 (PGE2) production. Both IFNgamma and carbachol triggered IFNgamma secretion in SMG. We here show that during local acute inflammation (LAI) induced by intraglandular injection of bacterial endotoxin, lypopolisaccharide (LPS), amylase secretion is decreased in comparison to control glands. We also observed that the muscarinic agonist carbachol stimulates in a dose-dependent manner amylase activity by M2 and M3 mAchR activation. Moreover, cyclooxygenase-2 (COX-2) activation and subsequent PGE2 liberation, in a nitric oxide independent manner, seem to be involved in M3 and M2 receptor activation by carbachol. In contrast, the addition of exogenous IFNgamma or carbachol inhibits the cytokine liberation in LAI glands.
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Affiliation(s)
- Alejandro J Español
- Departamento de Inmunobiología, Area Investigación, Instituto de Oncología Angel H. Roffo, Universidad de Buenos Aires, Buenos Aires, Argentina
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Piggott MA, Owens J, O'Brien J, Colloby S, Fenwick J, Wyper D, Jaros E, Johnson M, Perry RH, Perry EK. Muscarinic receptors in basal ganglia in dementia with Lewy bodies, Parkinson's disease and Alzheimer's disease. J Chem Neuroanat 2003; 25:161-73. [PMID: 12706204 DOI: 10.1016/s0891-0618(03)00002-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Derivatives of the muscarinic antagonist 3-quinuclidinyl-4-iodobenzilate (QNB), particularly [123I]-(R,R)-I-QNB, are currently being assessed as in vivo ligands to monitor muscarinic receptors in Alzheimer's disease (AD) and dementia with Lewy bodies (DLB), relating changes to disease symptoms and to treatment response with cholinergic medication. To assist in the evaluation of in vivo binding, muscarinic receptor density in post-mortem human brain was measured by autoradiography with [125I]-(R,R)-I-QNB and [125I]-(R,S)-I-QNB and compared to M1 ([3H]pirenzepine) and M2 and M4 ([3H]AF-DX 384) receptor binding. Binding was calculated in tissue containing striatum, globus pallidus (GPe), claustrum, and cingulate and insula cortex, in cases of AD, DLB, Parkinson's disease (PD) and normal elderly controls. Pirenzepine, AF-DX 384 and (R,S)-I-QNB binding in the striatum correlated positively with increased Alzheimer-type pathology, and AF-DX 384 and (R,R)-I-QNB cortical binding correlated positively with increased Lewy body (LB) pathology; however, striatal pirenzepine binding correlated negatively with cortical LB pathology. M1 receptors were significantly reduced in striatum in DLB compared to AD, PD, and controls and there was a significant correlation between M1 and dopamine D2 receptor densities. [3H]AF-DX 384 binding was higher in the striatum and GPe in AD. Binding of [125I]-(R,R)-I-QNB, which may reflect increased muscarinic M4 receptors, was higher in cortex and claustrum in DLB and AD. [125I]-(R,S)-I-QNB binding was higher in the GPe in AD. Low M1 and D2 receptors in DLB imply altered regulation of the striatal projection neurons which express these receptors. Low density of striatal M1 receptors may relate to the extent of movement disorder in DLB, and to a reduced risk of parkinsonism with acetylcholinesterase inhibition.
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Affiliation(s)
- Margaret A Piggott
- MRC/University of Newcastle Centre in Clinical Brain Ageing, MRC Building, Newcastle General Hospital, Westgate Road, NE4 6BE, Newcastle-upon-Tyne, UK.
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Misane I, Ogren SO. Selective 5-HT1A antagonists WAY 100635 and NAD-299 attenuate the impairment of passive avoidance caused by scopolamine in the rat. Neuropsychopharmacology 2003; 28:253-64. [PMID: 12589378 DOI: 10.1038/sj.npp.1300024] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Systemic administration of the muscarinic-receptor antagonists atropine and scopolamine produces cognitive deficits in humans, nonhuman primates and rodents. In humans, these deficits resemble symptoms of dementia seen in Alzheimer's disease. The passive avoidance (PA) task has been one of the most frequently used animal models for studying cholinergic mechanisms in learning and memory. The present study examined the ability of two selective 5-HT(1A) receptor antagonists WAY 100635 and NAD-299 (robalzotan) and two acetylcholinesterase (AChE) inhibitors tacrine and donepezil to attenuate the impairment of PA retention caused by the nonselective muscarinic receptor antagonist scopolamine in the rat. Although demonstrating differences in their temporal kinetics, both WAY 100635 and NAD-299 attenuated the impairment of PA caused by scopolamine (0.3 mg/kg s.c.). Donepezil did not block the PA deficit caused by the 0.3 mg/kg dose of scopolamine, but it prevented the inhibitory effects of the 0.2 mg/kg dose of scopolamine. In contrast, tacrine was effective vs both the 0.2 and 0.3 mg/kg doses of scopolamine. These results indicate that (1). a functional 5-HT(1A) receptor antagonism can attenuate the anterograde amnesia produced by muscarinic-receptor blockade, and (2). the AChE inhibitors tacrine and donepezil differ in their ability to modify muscarinic-receptor-mediated function in vivo. These results suggest that 5-HT(1A) receptor antagonists may have a potential in the treatment of cognitive symptoms in psychopathologies characterized by reduced ACh transmission such as Alzheimer's disease.
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Affiliation(s)
- Ilga Misane
- Deparment of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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Abstract
Dementia with Lewy bodies (DLB) is a relatively recently characterised syndrome with clinical and pathological features that distinguish it from classical Alzheimer's disease. These characteristics include more rapid decline, spontaneous features of parkinsonism, visual hallucinations and fluctuating cognition. This article reviews the clinical syndrome of DLB and the agents used to treat its cognitive, motor and behavioural manifestations. Benefit-risk issues regarding the treatment of DLB are discussed based upon limited randomised, controlled clinical trials with some speculative conclusions being drawn from case reports and case series. We conclude that patients with DLB may respond better to cholinesterase inhibitors than patients with Alzheimer's disease on both cognitive and behavioural measures. Cholinesterase inhibitor therapy may result in reduced caregiver burden and less time institutionalised. These agents are well tolerated with the majority of adverse effects being gastrointestinal in nature. Although neuropsychiatric manifestations are numerous in patients with DLB, antipsychotics should be used infrequently and with caution, although atypical antipsychotics are better tolerated than conventional antipsychotics. Physicians should exhibit caution when prescribing these agents because of the increased risk of extrapyramidal adverse effects. Limited data suggest that the use of levodopa or other dopaminergic agents may be of benefit for the treatment of the parkinsonism that is associated with DLB. However, the increased risk of hallucinations and neuropsychiatric symptoms may negate the potential benefits of increased mobility. There is insufficient evidence to draw conclusions about the use of antidepressants; however, selective serotonin reuptake inhibitors may be of benefit.
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Affiliation(s)
- Margaret M Swanberg
- Department of Neurology, UCLA School of Medicine, Los Angeles, California 90095-1769, USA
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Piggott M, Owens J, O'Brien J, Paling S, Wyper D, Fenwick J, Johnson M, Perry R, Perry E. Comparative distribution of binding of the muscarinic receptor ligands pirenzepine, AF-DX 384, (R,R)-I-QNB and (R,S)-I-QNB to human brain. J Chem Neuroanat 2002; 24:211-23. [PMID: 12297267 DOI: 10.1016/s0891-0618(02)00066-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Quinuclidinyl benzilate (QNB) and its derivatives are being developed to investigate muscarinic receptor changes in vivo in Alzheimer's disease and dementia with Lewy bodies. This is the first study of [125I]-(R,R)-I-QNB and [125I]-(R,S)-I-QNB binding in vitro in human brain. We have compared the in vitro binding of the muscarinic ligands [3H]pirenzepine and [3H]AF-DX 384, which have selectivity for the M1 and M2/M4 receptor subtypes, respectively, to the binding of [125I]-(R,R)-I-QNB and [125I]-(R,S)-I-QNB. This will provide a guide to the interpretation of in vivo SPET images generated with [123I]-(R,R)-I-QNB and [123I]-(R,S)-I-QNB. Binding was investigated in striatum, globus pallidus, thalamus and cerebellum, and cingulate, insula, temporal and occipital cortical areas, which show different proportions of muscarinic receptor subtypes, in post-mortem brain from normal individuals. M1 receptors are of high density in cortex and striatum and are relatively low in the thalamus and cerebellum, while M4 receptors are mainly expressed in the striatum, and M2 receptors are most evident in the cerebellum and thalamus. [125I]-(R,R)-I-QNB and [125I]-(R,S)-I-QNB density distribution patterns were consistent with binding to both M1 and M4 receptors, with [125I]-(R,R)-I-QNB additionally binding to a non-cholinergic site not displaceable by atropine. This distribution can be exploited by in vivo imaging, developing ligands for both SPET and PET, to reveal muscarinic receptor changes in Alzheimer's disease and dementia with Lewy bodies during the disease process and following cholinergic therapy.
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Affiliation(s)
- Margaret Piggott
- Newcastle General Hospital, MRC/University of Newcastle Centre Development in Clinical Brain Ageing, MRC Building, Westgate Road, NE4 6BE, Newcastle-upon-Tyne, UK.
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Abstract
DLB is a complex disorder with important associations with PD and AD. As clinicians, it is important for us to identify these patients because of their unique responses to medical interventions and to help patients and caregivers more fully understand this disease process and its implications. Further research is needed to improve our understanding of the pathophysiology of this important dementing disorder, with the ultimate goal of improving clinical management of this disease.
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Affiliation(s)
- James B Leverenz
- Department of Veterans Affairs, Northwest Network Mental Illness and Parkinson's Disease Research, Education and Clinical Centers, Seattle, WA, 98108 USA.
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Tayebati SK, Amenta F, El-Assouad D, Zaccheo D. Muscarinic cholinergic receptor subtypes in the hippocampus of aged rats. Mech Ageing Dev 2002; 123:521-8. [PMID: 11796137 DOI: 10.1016/s0047-6374(01)00353-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In spite of the suggestion of impaired muscarinic function in adult-onset cognitive disorders, data on the expression of muscarinic receptors in the hippocampus as a function of age are inconsistent. One reason may be that the majority of investigations were unable to differentiate the five brain muscarinic receptors subtypes. In this study, using a protocol based on a combination of both kinetic and equilibrium binding approaches, we have assessed the expression and the density of M1-M5 muscarinic cholinergic receptors in the hippocampus of Fisher 344 rats aged 6, 15 and 22 months. An age-related decrease of the density of M1 receptor was found in pyramidal neurons of the CA1 subfield. In this area, other subtypes of muscarinic receptors were unchanged with the exception of a loss of M2 receptor in the radial layer. In the CA3 subfield, receptor changes involved M2, M3 and M5 subtypes, whereas in the dentate gyrus, the main changes affected M1 and M2 receptors of the granular layer and M2 and M3 receptors of the molecular layer. The above findings indicate that analysis of age-related changes of different muscarinic cholinergic receptors might represent a useful contribution to identifying the basis of cholinergic neurotransmission impairment in adult-onset cognitive dysfunction.
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Affiliation(s)
- Seyed Khosrow 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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Shiozaki K, Iseki E, Hino H, Kosaka K. Distribution of m1 muscarinic acetylcholine receptors in the hippocampus of patients with Alzheimer's disease and dementia with Lewy bodies-an immunohistochemical study. J Neurol Sci 2001; 193:23-8. [PMID: 11718746 DOI: 10.1016/s0022-510x(01)00638-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Of the five subtypes (m1-m5) of muscarinic acetylcholine receptors (mAChR), the m1 subtype is the most abundant in the human cerebral cortex and hippocampus. Impairment of the muscarinic cholinergic system in the brain may cause cognitive dysfunction in patients with Alzheimer's disease (AD), and choline esterase inhibitors (ChE-I) are used to improve cognitive dysfunction. Severe impairment of the cholinergic system has also been reported in the brains of subjects with dementia with Lewy bodies (DLB). There have been a few reports about the distribution of mAChR subtypes in the human brain. In the present study, we investigated the distribution of m1 mAChR in the human hippocampus using an antibody against the m1 subtype. In the control brains, m1 immunoreactivity was observed in the apical dendrites and cell bodies of granular neurons of the dentate gyrus and pyramidal neurons of CA1-3 and the subiculum. The dendrites and the cell bodies of the pyramidal neurons in layers III and V of the parahippocampal cortex and other temporal cortices were also positive for m1 immunoreactivity. This m1 immunoreactivity was markedly reduced in AD and DLB brains.
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Affiliation(s)
- K Shiozaki
- Department of Psychiatry, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa-ku, 236-0004, Yokohama, Japan.
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Abstract
Diffuse Lewy body disease (DLB) is a neurodegenerative disorder characterized by dementia, fluctuations in mental status, hallucinations, and parkinsonism. Diffuse Lewy body disease is the second most common cause of dementia, following Alzheimer's disease. The treatment of DLB includes cholinergic therapy for cognitive impairment, atypical neuroleptics to alleviate hallucinations, and levodopa/carbidopa to improve parkinsonism. The recognition and diagnosis of DLB has critical treatment implications. Centrally acting cholinesterase inhibitors, such as rivastigmine, donepezil, and galantamine partially reverse decreased cortical cholinergic activity and may improve cognition and neuropsychiatric symptoms in DLB. Rivastigmine has been demonstrated to improve cognition and neuropsychiatric symptoms in patients with DLB without worsening parkinsonian features. Due to the potential adverse events associated with neuroleptics in this population, treatment with cholinesterase inhibitors is currently considered first-line therapy in the treatment of hallucinations and mental status fluctuations in DLB. Exquisite sensitivity to neuroleptic medications is a hallmark of DLB and life-threatening complications have been reported. Caution should be exercised when implementing antipsychotic therapy for the treatment of behavioral disturbances of DLB. When required, atypical neuroleptics with the least extrapyramdial side effects, such as quetiapine, should be used. The parkinsonian features of DLB may respond to dopaminergic therapy with levodopa. If parkinsonian symptoms result in clinical disability, a trial of levodopa is warranted. Unfortunately, dopaminergic medications may worsen hallucinations. Because dopamine agonists have a greater tendency to induce hallucinations and somnolence, levodopa is the treatment of choice for parkinsonism in DLB. Rapid eye movement (REM) sleep behavior disorder (RBD) is now recognized as a feature of DLB. Awareness of the presence of this symptom in patients with DLB is important and treatment with low dose clonazepam may help. Cholinergic aumentation may also improve these symptoms in patients with DLB.
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Affiliation(s)
- Theresa A. Zesiewicz
- *Parkinson's Disease and Movement Disorders Center, University of South Florida, 4 Columbus Drive, South, Suite 410, Tampa, FL 33606, USA.
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Rho JM, Storey TW. Molecular ontogeny of major neurotransmitter receptor systems in the mammalian central nervous system: norepinephrine, dopamine, serotonin, acetylcholine, and glycine. J Child Neurol 2001; 16:271-280; discussion 281. [PMID: 11332462 DOI: 10.1177/088307380101600407] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Neurotransmitter receptors are critical elements in intercellular signaling within the central nervous system and are divided into two major types based on their molecular structure and biophysical properties. The first are ionotropic receptors--ligand-gated ion channels that directly affect the membrane potential via passage of permeant ions (such as sodium and calcium) and mediate fast synaptic transmission. The second type are slower metabotropic receptors that are also ligand gated but depend on an interaction with guanine nucleotide-binding proteins and mediate signal transduction by activating second-messenger systems within the cell. In the past two decades, a wealth of information has emerged regarding the molecular biology and pharmacology of classic neurotransmitter receptors (including adrenergic, dopaminergic, serotonergic, cholinergic, glycine, gamma-aminobutyric acid [GABA(A)], and glutamate receptors). Further, the distribution of subunits comprising these receptors has been extensively studied. This review focuses on the molecular ontogeny of several of the major neurotransmitter receptor systems in the mammalian central nervous system, highlighting the role that some of these may play during brain development and in certain pathologic states.
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Affiliation(s)
- J M Rho
- Department of Pediatrics, University of California at Irvine College of Medicine, USA
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Jellinger KA. Morphological substrates of mental dysfunction in Lewy body disease: an update. JOURNAL OF NEURAL TRANSMISSION. SUPPLEMENTUM 2001; 59:185-212. [PMID: 10961431 DOI: 10.1007/978-3-7091-6781-6_21] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Mental dysfunction including cognitive, behavioural changes, mood disorders, and psychosis are increasingly recognized in patients with Parkinson's disease (PD) and related disorders. Their morphological correlates are complex due to multiple system degeneration. CNS changes contributing to cognitive changes in PD include 1. Dysfunction of subcorticocortical networks with neuron losses in a) the dopaminergic nigrostriatal loop, causing striato-(pre)frontal deafferentation and mesocortico-limbic system (medial substantia nigra, ventral tegmentum); b) noradrenergic (locus coeruleus), and serotonergic systems (dorsal raphe nuclei), c) cholinergic forebrain system (nucleus basalis of Meynert, etc), and d) specific nuclei of amygdala and limbic system (thalamic nuclei, hippocampus); 2. Limbic and/or cortical Lewy body and Alzheimer type pathologies with loss of neurons and synapses, 3. Combination of subcortical, cortical, and other pathologies. In general, degeneration of subcortical and striato-frontal networks causes cognitive, executive, behavioural, and mood disorders but less severe dementia than cortical changes which, when present in sufficient numbers, are important factors for overt dementia. In PD, cortical tau pathology with similar or differential patterns than in Alzheimer disease (AD) shows significant linear correlation with cognitive decline. In dementia with Lewy bodies (DLB), the second most frequent cause of dementia in the elderly, cortical Lewy bodies (LB) may or may not be associated with amyloid plaques and neuritic AD lesions. They predominantly affect the limbic system with less frequent isocortical Braak stages, whereas the cholinergic forebrain system is more severely affected than in AD. Both neuritic degeneration in limbic system in PD and DLB and the density of cortical synapse markers correlate with neuritic AD pathology and less with cortical LB counts. Apolipoprotein E epsilon4 allele frequency may represent a common genetic background for both AD and LB pathologies but there are different proportions of plaques between DLB (less Abeta1-40) and AD (more frequent Abeta1-40). Familial parkinsonism with dementia, linked to chromosome 17 (frontotemporal dementia with Parkinsonism (FTDP-17), and other tauopathies pathologically resembling PD plus AD, are often related to mutations of the tau gene, whereas familial PD with alpha-synuclein and Parkin mutations usually show no cognitive impairment. Mood disorders, in particular depression, and psychotic complications in both PD and DLB are related to complex involvement of noradrenergic and serotonergic systems, not confirmed in AD with depression, and both the prefrontal and limbic dopaminergic systems. The specific contributions of cortical and subcortical pathologies to mental dysfunction in PD and related disorders, their relationship to AD, and their genetic and aetiological backgrounds await further elucidation.
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Affiliation(s)
- K A Jellinger
- Ludwig Boltzmann Institute of Clinical Neurobiology, Vienna, Austria.
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Abstract
Diffuse Lewy body disease (DLBD) has been studied from various viewpoints and, although clinical diagnostic criteria for DLBD have been proposed, diagnosis remains difficult. DLBD has been reported to be the second most common form of dementia in the aged, following Alzheimer-type dementia. It has, however, been clinically under-diagnosed. Therefore, the search for diagnostic markers for DLBD must continue. Very recently, 'dementia with Lewy bodies' (DLB) was proposed as a generic term for various forms of dementia with Lewy bodies, including DLBD and similar disorders. Cortical Lewy bodies are the most important pathologic marker for diagnosis of DLBD. At present, however, the mechanism responsible for cortical Lewy body formation has yet to be disclosed.
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Affiliation(s)
- K Kosaka
- Department of Psychiatry, Yokohama City University, Yokohama, Japan.
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