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Lista S, Vergallo A, Teipel SJ, Lemercier P, Giorgi FS, Gabelle A, Garaci F, Mercuri NB, Babiloni C, Gaire BP, Koronyo Y, Koronyo-Hamaoui M, Hampel H, Nisticò R. Determinants of approved acetylcholinesterase inhibitor response outcomes in Alzheimer's disease: relevance for precision medicine in neurodegenerative diseases. Ageing Res Rev 2023; 84:101819. [PMID: 36526257 DOI: 10.1016/j.arr.2022.101819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 11/11/2022] [Accepted: 12/09/2022] [Indexed: 12/14/2022]
Abstract
Acetylcholinesterase inhibitors (ChEI) are the global standard of care for the symptomatic treatment of Alzheimer's disease (AD) and show significant positive effects in neurodegenerative diseases with cognitive and behavioral symptoms. Although experimental and large-scale clinical evidence indicates the potential long-term efficacy of ChEI, primary outcomes are generally heterogeneous across outpatient clinics and regional healthcare systems. Sub-optimal dosing or slow tapering, heterogeneous guidelines about the timing for therapy initiation (prodromal versus dementia stages), healthcare providers' ambivalence to treatment, lack of disease awareness, delayed medical consultation, prescription of ChEI in non-AD cognitive disorders, contribute to the negative outcomes. We present an evidence-based overview of determinants, spanning genetic, molecular, and large-scale networks, involved in the response to ChEI in patients with AD and other neurodegenerative diseases. A comprehensive understanding of cerebral and retinal cholinergic system dysfunctions along with ChEI response predictors in AD is crucial since disease-modifying therapies will frequently be prescribed in combination with ChEI. Therapeutic algorithms tailored to genetic, biological, clinical (endo)phenotypes, and disease stages will help leverage inter-drug synergy and attain optimal combined response outcomes, in line with the precision medicine model.
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Affiliation(s)
- Simone Lista
- Memory Resources and Research Center (CMRR), Neurology Department, Gui de Chauliac University Hospital, Montpellier, France; School of Pharmacy, University of Rome "Tor Vergata", Rome, Italy.
| | - Andrea Vergallo
- Sorbonne University, Alzheimer Precision Medicine (APM), AP-HP, Pitié-Salpêtrière Hospital, Paris, France
| | - Stefan J Teipel
- German Center for Neurodegenerative Diseases (DZNE) Rostock/Greifswald, Rostock, Germany; Department of Psychosomatic Medicine and Psychotherapy, University Medicine Rostock, Rostock, Germany
| | - Pablo Lemercier
- Sorbonne University, Alzheimer Precision Medicine (APM), AP-HP, Pitié-Salpêtrière Hospital, Paris, France
| | - Filippo Sean Giorgi
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, Pisa, Italy
| | - Audrey Gabelle
- Memory Resources and Research Center (CMRR), Neurology Department, Gui de Chauliac University Hospital, Montpellier, France
| | - Francesco Garaci
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy; Casa di Cura "San Raffaele Cassino", Cassino, Italy
| | - Nicola B Mercuri
- Department of Systems Medicine, University of Rome "Tor Vergata", Rome, Italy; IRCCS Santa Lucia Foundation, Rome, Italy
| | - Claudio Babiloni
- Department of Physiology and Pharmacology "Erspamer", Sapienza University of Rome, Rome, Italy; Hospital San Raffaele Cassino, Cassino, Italy
| | - Bhakta Prasad Gaire
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Yosef Koronyo
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Maya Koronyo-Hamaoui
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Department of Biomedical Sciences, Division of Applied Cell Biology and Physiology, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Harald Hampel
- Sorbonne University, Alzheimer Precision Medicine (APM), AP-HP, Pitié-Salpêtrière Hospital, Paris, France
| | - Robert Nisticò
- School of Pharmacy, University of Rome "Tor Vergata", Rome, Italy; Laboratory of Pharmacology of Synaptic Plasticity, EBRI Rita Levi-Montalcini Foundation, Rome, Italy.
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Mohammadi S, Mahmoudi J, Farajdokht F, Asadi M, Pirsarabi P, Kazeminiaei SF, Parvizpour S, Sadigh-Eteghad S. Polymorphisms of nicotinic acetylcholine receptors in Alzheimer’s disease: a systematic review and data analysis. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2022. [DOI: 10.1186/s43042-022-00357-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Objective
This study was conducted to accomplish a better insight into the impact of single nucleotide polymorphisms (SNPs) of nicotinic acetylcholine receptors (nAChR) at the risk of Alzheimer’s disease (AD) and their possible pathogenicity.
Methods
We carried out a systemic review of accessible studies. The case–control studies were assessed by an electronic search of international and local databases to identify relevant studies on SNPs relating to nAChR genes in AD. Two reviewers evaluated the inclusion/exclusion criteria, summarized, and analyzed the extracted data. We used odds ratios (ORs) with 95% confidence intervals (CIs) for reporting our data. Online databases were checked for possible pathogenicity of statistically significant SNPs. Also, online databases, including NCBI, NIH, ClinVar, RegulomeDB, and Ensemble, were used to analyze and identify structure and function, DNA features, and flank sequencing in SNPs.
Results
Among all collected SNPs, rs4779978 and rs1827294 on CHRNA7, rs1044394 on CHRNA4, and rs1127314 on CHRNB2 showed statistically significant between AD cases and controls.
Conclusions
Some SNPs from the reviewed reports show evidence supporting their possible involvement in AD pathology. However, more comprehensive studies are necessary to identify the exact correlation and their role on the pathogenicity of disease.
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Kelly MJ, Breathnach C, Tracey KJ, Donnelly SC. Manipulation of the inflammatory reflex as a therapeutic strategy. Cell Rep Med 2022; 3:100696. [PMID: 35858588 PMCID: PMC9381415 DOI: 10.1016/j.xcrm.2022.100696] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 06/20/2021] [Accepted: 06/23/2022] [Indexed: 02/07/2023]
Abstract
The cholinergic anti-inflammatory pathway is the efferent arm of the inflammatory reflex, a neural circuit through which the CNS can modulate peripheral immune responses. Signals communicated via the vagus and splenic nerves use acetylcholine, produced by Choline acetyltransferase (ChAT)+ T cells, to downregulate the inflammatory actions of macrophages expressing α7 nicotinic receptors. Pre-clinical studies using transgenic animals, cholinergic agonists, vagotomy, and vagus nerve stimulation have demonstrated this pathway's role and therapeutic potential in numerous inflammatory diseases. In this review, we summarize what is understood about the inflammatory reflex. We also demonstrate how pre-clinical findings are being translated into promising clinical trials, and we draw particular attention to innovative bioelectronic methods of harnessing the cholinergic anti-inflammatory pathway for clinical use.
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Affiliation(s)
- Mark J Kelly
- Department of Clinical Medicine, Trinity College Dublin, Dublin, Ireland; Tallaght University Hospital, Dublin, Ireland
| | | | - Kevin J Tracey
- Center for Biomedical Science and Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY 11030, USA
| | - Seamas C Donnelly
- Department of Clinical Medicine, Trinity College Dublin, Dublin, Ireland; Tallaght University Hospital, Dublin, Ireland.
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4
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Di Lascio S, Fornasari D, Benfante R. The Human-Restricted Isoform of the α7 nAChR, CHRFAM7A: A Double-Edged Sword in Neurological and Inflammatory Disorders. Int J Mol Sci 2022; 23:ijms23073463. [PMID: 35408823 PMCID: PMC8998457 DOI: 10.3390/ijms23073463] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/13/2022] [Accepted: 03/21/2022] [Indexed: 12/13/2022] Open
Abstract
CHRFAM7A is a relatively recent and exclusively human gene arising from the partial duplication of exons 5 to 10 of the α7 neuronal nicotinic acetylcholine receptor subunit (α7 nAChR) encoding gene, CHRNA7. CHRNA7 is related to several disorders that involve cognitive deficits, including neuropsychiatric, neurodegenerative, and inflammatory disorders. In extra-neuronal tissues, α7nAChR plays an important role in proliferation, differentiation, migration, adhesion, cell contact, apoptosis, angiogenesis, and tumor progression, as well as in the modulation of the inflammatory response through the “cholinergic anti-inflammatory pathway”. CHRFAM7A translates the dupα7 protein in a multitude of cell lines and heterologous systems, while maintaining processing and trafficking that are very similar to the full-length form. It does not form functional ion channel receptors alone. In the presence of CHRNA7 gene products, dupα7 can assemble and form heteromeric receptors that, in order to be functional, should include at least two α7 subunits to form the agonist binding site. When incorporated into the receptor, in vitro and in vivo data showed that dupα7 negatively modulated α7 activity, probably due to a reduction in the number of ACh binding sites. Very recent data in the literature report that the presence of the duplicated gene may be responsible for the translational gap in several human diseases. Here, we will review the studies that have been conducted on CHRFAM7A in different pathologies, with the intent of providing evidence regarding when and how the expression of this duplicated gene may be beneficial or detrimental in the pathogenesis, and eventually in the therapeutic response, to CHRNA7-related neurological and non-neurological diseases.
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Affiliation(s)
- Simona Di Lascio
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), Università degli Studi di Milano, 20129 Milan, Italy; (S.D.L.); (D.F.)
| | - Diego Fornasari
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), Università degli Studi di Milano, 20129 Milan, Italy; (S.D.L.); (D.F.)
- CNR Institute of Neuroscience, 20845 Vedano al Lambro, Italy
| | - Roberta Benfante
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), Università degli Studi di Milano, 20129 Milan, Italy; (S.D.L.); (D.F.)
- CNR Institute of Neuroscience, 20845 Vedano al Lambro, Italy
- NeuroMi, Milan Center for Neuroscience, University of Milano Bicocca, 20126 Milan, Italy
- Correspondence:
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5
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Benfante R, Di Lascio S, Cardani S, Fornasari D. Acetylcholinesterase inhibitors targeting the cholinergic anti-inflammatory pathway: a new therapeutic perspective in aging-related disorders. Aging Clin Exp Res 2021; 33:823-834. [PMID: 31583530 DOI: 10.1007/s40520-019-01359-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 09/18/2019] [Indexed: 11/26/2022]
Abstract
Neuroinflammation and cholinergic dysfunction, leading to cognitive impairment, are hallmarks of aging and neurodegenerative disorders, including Alzheimer's disease (AD). Acetylcholinesterase inhibitors (AChEI), the symptomatic therapy in AD, attenuate and delay the cognitive deficit by enhancing cholinergic synapses. The α7 nicotinic acetylcholine (ACh) receptor has shown a double-edged sword feature, as it binds with high affinity Aβ1-42, promoting intracellular accumulation and Aβ-induced tau phosphorylation, but also exerts neuroprotection by stimulating anti-apoptotic pathways. Moreover, it mediates peripheral and central anti-inflammatory response, being the effector player of the activation of the cholinergic anti-inflammatory pathway (CAIP), that, by decreasing the release of TNF-α, IL-1β, and IL-6, it may have a role in improving cognition. The finding in preclinical models that, in addition to their major function (choline esterase inhibition) AChEIs have neuroprotective properties mediated via α7nAChR and modulate innate immunity, possibly as a result of the increased availability of acetylcholine activating the CAIP, pave the way for new pharmacological intervention in AD and other neurological disorders that are characterized by neuroinflammation. CHRFAM7A is a human-specific gene acting as a dominant negative inhibitor of α7nAChR function, also suggesting a role in affecting human cognition and memory by altering α7nAChR activities in the central nervous system (CNS). This review will summarize the current knowledge on the cholinergic anti-inflammatory pathway in aging-related disorders, and will argue that the presence of the human-restricted CHRFAM7A gene might play a fundamental role in the regulation of CAIP and in the response to AChEI.
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Affiliation(s)
- Roberta Benfante
- CNR-Neuroscience Institute, Via Vanvitelli 32, 20129, Milan, Italy.
- Dept. Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Via Vanvitelli 32, 20129, Milan, Italy.
| | - Simona Di Lascio
- Dept. Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Via Vanvitelli 32, 20129, Milan, Italy
| | - Silvia Cardani
- Dept. Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Via Vanvitelli 32, 20129, Milan, Italy
| | - Diego Fornasari
- CNR-Neuroscience Institute, Via Vanvitelli 32, 20129, Milan, Italy
- Dept. Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Via Vanvitelli 32, 20129, Milan, Italy
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6
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Ganeshpurkar A, Singh R, Kumar D, Divya, Shivhare S, Kumar A, Singh SK. Computational binding study with α7 nicotinic acetylcholine receptor of Anvylic-3288: an allosteric modulator. MOLECULAR SIMULATION 2020. [DOI: 10.1080/08927022.2020.1795166] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Ankit Ganeshpurkar
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Ravi Singh
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Devendra Kumar
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Divya
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Shalini Shivhare
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Ashok Kumar
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Sushil Kumar Singh
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
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Hoskin JL, Al-Hasan Y, Sabbagh MN. Nicotinic Acetylcholine Receptor Agonists for the Treatment of Alzheimer's Dementia: An Update. Nicotine Tob Res 2019; 21:370-376. [PMID: 30137524 DOI: 10.1093/ntr/nty116] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Accepted: 08/18/2018] [Indexed: 01/08/2023]
Abstract
A significant portion of the clinical phenotype observed in Alzheimer's disease (AD) occurs through nicotinic acetylcholine receptors (nAChRs). Degeneration of cholinergic neurons, combined with aberrant nAChR expression and activation partially through amyloid-beta peptide (Aβ)-nAChR leads to upregulation of pro-inflammatory pathways and subsequently the progressive cognitive decline of AD. Interestingly, the cholinergic anti-inflammatory pathway is also mediated through nAChR particularly α7 nAChR. Thus, agonists of these receptors will likely exert pro-cognitive benefits through multiple mechanisms including stimulating the cholinergic pathway, modulating inflammation, and buffering the effects of amyloid. Despite this promising theoretical use, trials thus far have been complicated by adverse effects or minimal improvement. This review will provide an update on several pharmacological nAChR agonists tested in clinical trials and reasons that further investigation of nAChR agonists is merited. IMPLICATIONS nAChRs have consistently presented a promising theoretical use in the treatment of AD; however, trials thus far have been complicated by adverse effects or minimal improvement. This review will provide an update on several pharmacological nAChR agonists trialed and reasons that further investigation of nAChR agonists is merited.
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Affiliation(s)
| | | | - Marwan Noel Sabbagh
- Barrow Neurological Institute, Phoenix, AZ.,Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, NV
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8
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Clarelli F, Mascia E, Santangelo R, Mazzeo S, Giacalone G, Galimberti D, Fusco F, Zuffi M, Fenoglio C, Franceschi M, Scarpini E, Forloni G, Magnani G, Comi G, Albani D, Martinelli Boneschi F. CHRNA7 Gene and Response to Cholinesterase Inhibitors in an Italian Cohort of Alzheimer's Disease Patients. J Alzheimers Dis 2017; 52:1203-8. [PMID: 27104904 DOI: 10.3233/jad-160074] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Previous studies suggest that genetic variants in CHRNA7, which encodes for the major subunit of the acetylcholine receptor (α7-nAChR), are associated with the clinical response to cholinesterase inhibitors (ChEI) in Alzheimer's disease (AD) patients. We sought to replicate the association of two SNPs in the CHRNA7 gene, rs6494223 and rs8024987, with response to ChEI treatment in an Italian cohort of 169 AD patients, further extending the study to gene-level analysis. None of the tested variants was associated with clinical response. However, rs6494223 showed a consistent effect direction (OR = 1.4; p = 0.17), which after meta-analysis with previous study yielded a significant result (OR = 1.57, p = 0.02, I2 = 0%).
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Affiliation(s)
- Ferdinando Clarelli
- Laboratory of Human Genetics of Neurological Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy
| | - Elisabetta Mascia
- Laboratory of Human Genetics of Neurological Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy
| | | | | | | | - Daniela Galimberti
- Neurology Unit, Department of Pathophysiology and Transplantation, University of Milan, Fondazione Cá Granda, IRCCS Ospedale Policlinico, Milan, Italy
| | - Federica Fusco
- IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri" via La Masa, Milan, Italy
| | - Marta Zuffi
- Department of Neurology, Multimedica Hospital Castellanza (Va), Castellanza, Italy
| | - Chiara Fenoglio
- Neurology Unit, Department of Pathophysiology and Transplantation, University of Milan, Fondazione Cá Granda, IRCCS Ospedale Policlinico, Milan, Italy
| | - Massimo Franceschi
- Department of Neurology, Multimedica Hospital Castellanza (Va), Castellanza, Italy
| | - Elio Scarpini
- Neurology Unit, Department of Pathophysiology and Transplantation, University of Milan, Fondazione Cá Granda, IRCCS Ospedale Policlinico, Milan, Italy
| | - Gianluigi Forloni
- IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri" via La Masa, Milan, Italy
| | | | - Giancarlo Comi
- Laboratory of Human Genetics of Neurological Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy.,Department of Neurology, San Raffaele Hospital, Milan, Italy
| | - Diego Albani
- IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri" via La Masa, Milan, Italy
| | - Filippo Martinelli Boneschi
- Laboratory of Human Genetics of Neurological Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy.,Department of Neurology, San Raffaele Hospital, Milan, Italy
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9
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Chrna7 deficient mice manifest no consistent neuropsychiatric and behavioral phenotypes. Sci Rep 2017; 7:39941. [PMID: 28045139 PMCID: PMC5206704 DOI: 10.1038/srep39941] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 11/28/2016] [Indexed: 11/22/2022] Open
Abstract
The alpha7 nicotinic acetylcholine receptor, encoded by the CHRNA7 gene, has been implicated in various psychiatric and behavioral disorders, including schizophrenia, bipolar disorder, epilepsy, autism, Alzheimer’s disease, and Parkinson’s disease, and is considered a potential target for therapeutic intervention. 15q13.3 microdeletion syndrome is a rare genetic disorder, caused by submicroscopic deletions on chromosome 15q. CHRNA7 is the only gene in this locus that has been deleted entirely in cases involving the smallest microdeletions. Affected individuals manifest variable neurological and behavioral phenotypes, which commonly include developmental delay/intellectual disability, epilepsy, and autism spectrum disorder. Subsets of patients have short attention spans, aggressive behaviors, mood disorders, or schizophrenia. Previous behavioral studies suggested that Chrna7 deficient mice had attention deficits, but were normal in baseline behavioral responses, learning, memory, and sensorimotor gating. Given a growing interest in CHRNA7-related diseases and a better appreciation of its associated human phenotypes, an in-depth behavioral characterization of the Chrna7 deficient mouse model appeared prudent. This study was designed to investigate whether Chrna7 deficient mice manifest phenotypes related to those seen in human individuals, using an array of 12 behavioral assessments and electroencephalogram (EEG) recordings on freely-moving mice. Examined phenotypes included social interaction, compulsive behaviors, aggression, hyperactivity, anxiety, depression, and somatosensory gating. Our data suggests that mouse behavior and EEG recordings are not sensitive to decreased Chrna7 copy number.
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Weng PH, Chen JH, Chen TF, Sun Y, Wen LL, Yip PK, Chu YM, Chen YC. CHRNA7 Polymorphisms and Dementia Risk: Interactions with Apolipoprotein ε4 and Cigarette Smoking. Sci Rep 2016; 6:27231. [PMID: 27249957 PMCID: PMC4890170 DOI: 10.1038/srep27231] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 02/15/2016] [Indexed: 12/16/2022] Open
Abstract
α7 nicotinic acetylcholine receptor (α7nAChR, encoded by CHRNA7) is involved in dementia pathogenesis through cholinergic neurotransmission, neuroprotection and interactions with amyloid-β. Smoking promotes atherosclerosis and increases dementia risk, but nicotine exerts neuroprotective effect via α7nAChR in preclinical studies. No studies explored the gene-gene, gene-environment interactions between CHRNA7 polymorphism, apolipoprotein E (APOE) ε4 status and smoking on dementia risk. This case-control study recruited 254 late-onset Alzheimer’s disease (LOAD) and 115 vascular dementia (VaD) cases (age ≥65) from the neurology clinics of three teaching hospitals in Taiwan during 2007–2010. Controls (N = 435) were recruited from health checkup programs and volunteers during the same period. Nine CHRNA7 haplotype-tagging single nucleotide polymorphisms representative for Taiwanese were genotyped. Among APOE ε4 non-carriers, CHRNA7 rs7179008 variant carriers had significantly decreased LOAD risk after correction for multiple tests (GG + AG vs. AA: adjusted odds ratio = 0.29, 95% confidence interval = 0.13–0.64, P = 0.002). Similar findings were observed for carriers of GT haplotype in CHRNA7 block4. A significant interaction was found between rs7179008, GT haplotype in block4 and APOE ε4 on LOAD risk. rs7179008 variant also reduced the detrimental effect of smoking on LOAD risk. No significant association was found between CHRNA7 and VaD. These findings help to understand dementia pathogenesis.
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Affiliation(s)
- Pei-Hsuan Weng
- Department of Family Medicine, Taiwan Adventist Hospital, Taipei, Taiwan.,Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan
| | - Jen-Hau Chen
- Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.,Department of Geriatrics and Gerontology, National Taiwan University Hospital, Taipei, Taiwan
| | - Ta-Fu Chen
- Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yu Sun
- Department of Neurology, En Chu Kong Hospital, New Taipei City, Taiwan
| | - Li-Li Wen
- Department of Laboratory Medicine, En Chu Kong Hospital, New Taipei City, Taiwan
| | - Ping-Keung Yip
- School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan.,Center of Neurological Medicine, Cardinal Tien Hospital, New Taipei City, Taiwan
| | - Yi-Min Chu
- Department of Laboratory Medicine, Cardinal Tien Hospital, New Taipei City, Taiwan
| | - Yen-Ching Chen
- Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.,Department of Public Health, College of Public Health, National Taiwan University, Taipei, Taiwan.,Research Center for Genes, Environment and Human Health, College of Public Health, National Taiwan University, Taipei, Taiwan
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11
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Bertrand D, Lee CHL, Flood D, Marger F, Donnelly-Roberts D. Therapeutic Potential of α7 Nicotinic Acetylcholine Receptors. Pharmacol Rev 2015; 67:1025-73. [DOI: 10.1124/pr.113.008581] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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12
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Sinkus ML, Graw S, Freedman R, Ross RG, Lester HA, Leonard S. The human CHRNA7 and CHRFAM7A genes: A review of the genetics, regulation, and function. Neuropharmacology 2015; 96:274-88. [PMID: 25701707 PMCID: PMC4486515 DOI: 10.1016/j.neuropharm.2015.02.006] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 02/04/2015] [Accepted: 02/06/2015] [Indexed: 01/16/2023]
Abstract
The human α7 neuronal nicotinic acetylcholine receptor gene (CHRNA7) is ubiquitously expressed in both the central nervous system and in the periphery. CHRNA7 is genetically linked to multiple disorders with cognitive deficits, including schizophrenia, bipolar disorder, ADHD, epilepsy, Alzheimer's disease, and Rett syndrome. The regulation of CHRNA7 is complex; more than a dozen mechanisms are known, one of which is a partial duplication of the parent gene. Exons 5-10 of CHRNA7 on chromosome 15 were duplicated and inserted 1.6 Mb upstream of CHRNA7, interrupting an earlier partial duplication of two other genes. The chimeric CHRFAM7A gene product, dupα7, assembles with α7 subunits, resulting in a dominant negative regulation of function. The duplication is human specific, occurring neither in primates nor in rodents. The duplicated α7 sequence in exons 5-10 of CHRFAM7A is almost identical to CHRNA7, and thus is not completely queried in high throughput genetic studies (GWAS). Further, pre-clinical animal models of the α7nAChR utilized in drug development research do not have CHRFAM7A (dupα7) and cannot fully model human drug responses. The wide expression of CHRNA7, its multiple functions and modes of regulation present challenges for study of this gene in disease. This article is part of the Special Issue entitled 'The Nicotinic Acetylcholine Receptor: From Molecular Biology to Cognition'.
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Affiliation(s)
- Melissa L Sinkus
- Department of Psychiatry, University of Colorado Denver, Aurora, CO 80045, USA.
| | - Sharon Graw
- Department of Psychiatry, University of Colorado Denver, Aurora, CO 80045, USA.
| | - Robert Freedman
- Department of Psychiatry, University of Colorado Denver, Aurora, CO 80045, USA; Veterans Affairs Medical Research Center, Denver, CO 80262, USA.
| | - Randal G Ross
- Department of Psychiatry, University of Colorado Denver, Aurora, CO 80045, USA.
| | - Henry A Lester
- Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA.
| | - Sherry Leonard
- Department of Psychiatry, University of Colorado Denver, Aurora, CO 80045, USA; Veterans Affairs Medical Research Center, Denver, CO 80262, USA.
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Thomsen MS, Zwart R, Ursu D, Jensen MM, Pinborg LH, Gilmour G, Wu J, Sher E, Mikkelsen JD. α7 and β2 Nicotinic Acetylcholine Receptor Subunits Form Heteromeric Receptor Complexes that Are Expressed in the Human Cortex and Display Distinct Pharmacological Properties. PLoS One 2015; 10:e0130572. [PMID: 26086615 PMCID: PMC4472343 DOI: 10.1371/journal.pone.0130572] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 05/21/2015] [Indexed: 12/03/2022] Open
Abstract
The existence of α7β2 nicotinic acetylcholine receptors (nAChRs) has recently been demonstrated in both the rodent and human brain. Since α7-containing nAChRs are promising drug targets for schizophrenia and Alzheimer’s disease, it is critical to determine whether α7β2 nAChRs are present in the human brain, in which brain areas, and whether they differ functionally from α7 nAChR homomers. We used α-bungarotoxin to affinity purify α7-containing nAChRs from surgically excised human temporal cortex, and found that α7 subunits co-purify with β2 subunits, indicating the presence of α7β2 nAChRs in the human brain. We validated these results by demonstrating co-purification of β2 from wild-type, but not α7 or β2 knock-out mice. The pharmacology and kinetics of human α7β2 nAChRs differed significantly from that of α7 homomers in response to nAChR agonists when expressed in Xenopus oocytes and HEK293 cells. Notably, α7β2 heteromers expressed in HEK293 cells display markedly slower rise and decay phases. These results demonstrate that α7 subunits in the human brain form heteromeric complexes with β2 subunits, and that human α7β2 nAChR heteromers respond to nAChR agonists with a unique pharmacology and kinetic profile. α7β2 nAChRs thus represent an alternative mechanism for the reported clinical efficacy of α7 nAChR ligands.
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Affiliation(s)
- Morten Skøtt Thomsen
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Ruud Zwart
- Lilly Research Centre, Eli Lilly and Company Limited, Erl Wood Manor, United Kingdom
| | - Daniel Ursu
- Lilly Research Centre, Eli Lilly and Company Limited, Erl Wood Manor, United Kingdom
| | - Majbrit Myrup Jensen
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Lars Hageman Pinborg
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
- Epilepsy Clinic, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Gary Gilmour
- Lilly Research Centre, Eli Lilly and Company Limited, Erl Wood Manor, United Kingdom
| | - Jie Wu
- Divisions of Neurology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, United States of America
| | - Emanuele Sher
- Lilly Research Centre, Eli Lilly and Company Limited, Erl Wood Manor, United Kingdom
| | - Jens Damsgaard Mikkelsen
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
- * E-mail:
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Braga ILS, Silva PN, Furuya TK, Santos LC, Pires BC, Mazzotti DR, Bertolucci PH, Cendoroglo MS, Smith MC. Effect of APOE and CHRNA7 genotypes on the cognitive response to cholinesterase inhibitor treatment at different stages of Alzheimer's disease. Am J Alzheimers Dis Other Demen 2015; 30:139-44. [PMID: 24951635 PMCID: PMC10852661 DOI: 10.1177/1533317514539540] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The loss of cholinergic transmission is considered to be an important cause of Alzheimer's disease (AD). Treatment with acetyl cholinesterase inhibitors (ChEIs) shows benefits; however, great heterogeneity has been observed in patient responses. We evaluated apolipoprotein E (APOE) and α7 nicotinic receptor (CHRNA7) single-nucleotide polymorphisms (SNPs) and associated these SNPs with pharmacological responses to ChEIs in a Brazilian population with AD. We studied 177 outpatients using ChEIs, and they were classified as responders and nonresponders according to variation in Mini-Mental State Examination (MMSE) status. The analysis of APOE genotypes showed that patients with the ε4 allele had a worse response than those without the ε4 allele. We observed an association between the CHRNA7 T allele and a better response to treatment with ChEIs in patients with mild AD (MMSE ≥ 20). The SNP rs6494223 of CHRNA7 as well as APOEε4 could be useful for understanding the response to ChEI treatment in patients with AD.
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Affiliation(s)
- Ianna Lacerda Sampaio Braga
- Disciplina de Genética, Departamento de Morfologia e Genética, Universidade Federal de São Paulo (UNIFESP), São Paulo-SP, Brazil
| | - Patricia Natalia Silva
- Disciplina de Genética, Departamento de Morfologia e Genética, Universidade Federal de São Paulo (UNIFESP), São Paulo-SP, Brazil
| | - Tatiane Katsue Furuya
- Disciplina de Genética, Departamento de Morfologia e Genética, Universidade Federal de São Paulo (UNIFESP), São Paulo-SP, Brazil
| | - Leonardo Caires Santos
- Disciplina de Genética, Departamento de Morfologia e Genética, Universidade Federal de São Paulo (UNIFESP), São Paulo-SP, Brazil
| | - Belisa Caldana Pires
- Disciplina de Genética, Departamento de Morfologia e Genética, Universidade Federal de São Paulo (UNIFESP), São Paulo-SP, Brazil
| | - Diego Robles Mazzotti
- Disciplina de Genética, Departamento de Morfologia e Genética, Universidade Federal de São Paulo (UNIFESP), São Paulo-SP, Brazil
| | - Paulo Henrique Bertolucci
- Disciplina de Neurologia Clínica, Departamento de Neurologia e Neurocirurgia (UNIFESP), São Paulo-SP, Brazil
| | - Maysa Seabra Cendoroglo
- Disciplina de Geriatria e Gerontologia, Departamento de Medicina (UNIFESP), São Paulo-SP, Brazil
| | - Marília Cardoso Smith
- Disciplina de Genética, Departamento de Morfologia e Genética, Universidade Federal de São Paulo (UNIFESP), São Paulo-SP, Brazil
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Jensen MM, Arvaniti M, Mikkelsen JD, Michalski D, Pinborg LH, Härtig W, Thomsen MS. Prostate stem cell antigen interacts with nicotinic acetylcholine receptors and is affected in Alzheimer's disease. Neurobiol Aging 2015; 36:1629-1638. [PMID: 25680266 DOI: 10.1016/j.neurobiolaging.2015.01.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 12/08/2014] [Accepted: 01/03/2015] [Indexed: 01/13/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder involving impaired cholinergic neurotransmission and dysregulation of nicotinic acetylcholine receptors (nAChRs). Ly-6/neurotoxin (Lynx) proteins have been shown to modulate cognition and neural plasticity by binding to nAChR subtypes and modulating their function. Hence, changes in nAChR regulatory proteins such as Lynx proteins could underlie the dysregulation of nAChRs in AD. Using Western blotting, we detected bands corresponding to the Lynx proteins prostate stem cell antigen (PSCA) and Lypd6 in human cortex indicating that both proteins are present in the human brain. We further showed that PSCA forms stable complexes with the α4 nAChR subunit and decreases nicotine-induced extracellular-signal regulated kinase phosphorylation in PC12 cells. In addition, we analyzed protein levels of PSCA and Lypd6 in postmortem tissue of medial frontal gyrus from AD patients and found significantly increased PSCA levels (approximately 70%). In contrast, no changes in Lypd6 levels were detected. In concordance with our findings in AD patients, PSCA levels were increased in the frontal cortex of triple transgenic mice with an AD-like pathology harboring human transgenes that cause both age-dependent β-amyloidosis and tauopathy, whereas Tg2576 mice, which display β-amyloidosis only, had unchanged PSCA levels compared to wild-type animals. These findings identify PSCA as a nAChR-binding protein in the human brain that is affected in AD, suggesting that PSCA-nAChR interactions may be involved in the cognitive dysfunction observed in AD.
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Affiliation(s)
- Majbrit M Jensen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Maria Arvaniti
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Jens D Mikkelsen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | | | - Lars H Pinborg
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark; Epilepsy Clinic, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Wolfgang Härtig
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Morten S Thomsen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
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CHRNA7 polymorphisms and response to cholinesterase inhibitors in Alzheimer's disease. PLoS One 2013; 8:e84059. [PMID: 24391883 PMCID: PMC3877150 DOI: 10.1371/journal.pone.0084059] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 11/19/2013] [Indexed: 12/26/2022] Open
Abstract
Background CHRNA7 encodes the α7 nicotinic acetylcholine receptor subunit, which is important to Alzheimer's disease (AD) pathogenesis and cholinergic neurotransmission. Previously, CHRNA7 polymorphisms have not been related to cholinesterase inhibitors (ChEI) response. Methods Mild to moderate AD patients received ChEIs were recruited from the neurology clinics of three teaching hospitals from 2007 to 2010 (n = 204). Nine haplotype-tagging single nucleotide polymorphisms of CHRNA7 were genotyped. Cognitive responders were those showing improvement in the Mini-Mental State Examination score ≧2 between baseline and 6 months after ChEI treatment. Results AD women carrying rs8024987 variants [GG+GC vs. CC: adjusted odds ratio (AOR) = 3.62, 95% confidence interval (CI) = 1.47–8.89] and GG haplotype in block1 (AOR = 3.34, 95% CI = 1.38–8.06) had significantly better response to ChEIs (false discovery rate <0.05). These variant carriers using galantamine were 11 times more likely to be responders than female non-carriers using donepezil or rivastigmine. Conclusion For the first time, this study found a significant association between CHRNA7 polymorphisms and better ChEI response. If confirmed by further studies, CHRNA7 polymorphisms may aid in predicting ChEI response and refining treatment choice.
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Ravert HT, Dorff P, Foss CA, Mease RC, Fan H, Holmquist CR, Phillips E, McCarthy DJ, Heys JR, Holt DP, Wang Y, Endres CJ, Dannals RF, Pomper MG. Radiochemical synthesis and in vivo evaluation of [18F]AZ11637326: an agonist probe for the α7 nicotinic acetylcholine receptor. Nucl Med Biol 2013; 40:731-9. [PMID: 23680470 DOI: 10.1016/j.nucmedbio.2013.04.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 03/27/2013] [Accepted: 04/09/2013] [Indexed: 10/26/2022]
Abstract
INTRODUCTION The alpha-7 nicotinic acetylcholine receptor (α7 nAChR) is key in brain communication and has been implicated in the pathophysiology of diseases of the central nervous system. A positron-emitting radioligand targeting the α7 nAChR would enable better understanding of a variety of neuropsychiatric illnesses, including schizophrenia and Alzheimer's disease, and could enhance the development of new drugs for these and other conditions. We describe our attempt to synthesize an α7 nAChR-selective radiotracer for positron emission tomography (PET). METHODS We prepared the high-affinity (K(d) = 0.2 nM) α7 nAChR agonist, 5'-(2-[(18)F]fluorophenyl)spiro[1-azabicyclo-[2.2.2]octane]-3,2'-(3'H)furo[2,3-b]pyridine, [(18)F]AZ11637326, in two steps, a nucleophilic fluorination followed by decarbonylation. We studied [(18)F]AZ11637326 in rodents, including mice lacking α7 nAChR, and in non-human primates. RESULTS [(18)F]AZ11637326 was synthesized in a non-decay-corrected radiochemical yield of 3% from the end of synthesis (90 min) with a radiochemical purity >90% and average specific radioactivity of 140GBq/μmol (3,781 mCi/μmol). Modest rodent brain uptake was observed (2-5% injected dose per gram of tissue, depending on specific activity), with studies comparing CD-1 and α7 nAChR null mice indicating an element of target-specific binding. Blocking studies in non-human primates did not reveal specific binding within the brain. CONCLUSION Despite the high affinity and target selectivity of AZ11637326 for α7 nAChR in vitro and encouraging rodent studies, receptor-mediated binding could not be demonstrated in non-human primates. Further structural optimization of compounds of this class will be required for them to serve as suitable radiotracers for PET.
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Affiliation(s)
- Hayden T Ravert
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical School, Baltimore, MD 21287-0014, USA
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Maier DL, Hill G, Ding M, Tuke D, Einstein E, Gurley D, Gordon JC, Bock MJ, Smith JS, Bialecki R, Eisman M, Elmore CS, Werkheiser JL. Pre-clinical validation of a novel alpha-7 nicotinic receptor radiotracer, [3H]AZ11637326: Target localization, biodistribution and ligand occupancy in the rat brain. Neuropharmacology 2011; 61:161-71. [DOI: 10.1016/j.neuropharm.2011.03.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 03/03/2011] [Accepted: 03/30/2011] [Indexed: 11/15/2022]
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Joo EJ, Lee KY, Kim HS, Kim SH, Ahn YM, Kim YS. Genetic Association Study of the Alpha 7 Nicotinic Receptor (CHRNA7) with the Development of Schizophrenia and Bipolar Disorder in Korean Population. Psychiatry Investig 2010; 7:196-201. [PMID: 20927308 PMCID: PMC2947807 DOI: 10.4306/pi.2010.7.3.196] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 06/06/2010] [Accepted: 07/04/2010] [Indexed: 01/29/2023] Open
Abstract
OBJECTIVE CHRNA7 has been shown to be a strong candidate gene for schizophrenia and bipolar disorder. It is located on chromosome 15q13-q14, which is one of the replicated linkage spots for schizophrenia and bipolar disorder. METHODS We conducted an association study to determine whether previous positive association is replicable in the Korean population. We included 254 patients with schizophrenia, 193 patients with bipolar disorder type I, 38 patients with bipolar disorder type II, 64 schizoaffective disorder patients, and 349 controls. All subjects were ethnically Korean. A total of 898 subjects were included, and genotyping was done for three single nucleotide polymorphisms (SNPs) of CHRNA7. These three intronic SNPs were rs2337506 (A/G), rs6494223 (C/T), and rs12916879 (A/G). RESULTS There was only one marginally significant association; this association was between rs12916879 and bipolar disorder type I in the male subgroup. In both the allele and genotype distributions, we found a weak signal (Chi-squared=3.57, df=1, p=0.06 for allele, Chi-squared=7.50, df=2, p=0.02 for genotype) only. Unphased haplotype analysis could not provide additional support for this finding. No SNP was associated with schizophrenia or any other affected groups in this Korean sample. The associative finding is marginal and inconclusive. CONCLUSION We could not replicate positive association in other ethnic groups previously studied. This suggests possible heterogeneity in the genes associated with schizophrenia and bipolar disorders. Because of structural complexity of the CHRNA7 gene and the limited statistical power of this study, further genetic studies with more SNPs and larger samples covering various populations, along with more fine molecular exploration of the CHRNA7 gene structure, are required.
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Affiliation(s)
- Eun-Jeong Joo
- Department of Neuropsychiatry, Eulji University School of Medicine, Eulji General Hospital, Seoul, Korea
| | - Kyu Young Lee
- Department of Neuropsychiatry, Eulji University School of Medicine, Eulji General Hospital, Seoul, Korea
| | - Hyun Sook Kim
- College of Nursing, Eulji University, Seongnam, Korea
| | - Se Hyun Kim
- Department of Psychiatry and Behavioral Science, Seoul National University College of Medicine, Seoul, Korea
- Institute of Human Behavioral Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Yong Min Ahn
- Department of Psychiatry and Behavioral Science, Seoul National University College of Medicine, Seoul, Korea
| | - Yong Sik Kim
- Department of Psychiatry and Behavioral Science, Seoul National University College of Medicine, Seoul, Korea
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Heinzen EL, Need AC, Hayden KM, Chiba-Falek O, Roses AD, Strittmatter WJ, Burke JR, Hulette CM, Welsh-Bohmer KA, Goldstein DB. Genome-wide scan of copy number variation in late-onset Alzheimer's disease. J Alzheimers Dis 2010; 19:69-77. [PMID: 20061627 DOI: 10.3233/jad-2010-1212] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Alzheimer's disease is a complex and progressive neurodegenerative disease leading to loss of memory, cognitive impairment, and ultimately death. To date, six large-scale genome-wide association studies have been conducted to identify SNPs that influence disease predisposition. These studies have confirmed the well-known APOE epsilon4 risk allele, identified a novel variant that influences disease risk within the APOE epsilon4 population, found a SNP that modifies the age of disease onset, as well as reported the first sex-linked susceptibility variant. Here we report a genome-wide scan of Alzheimer's disease in a set of 331 cases and 368 controls, extending analyses for the first time to include assessments of copy number variation. In this analysis, no new SNPs show genome-wide significance. We also screened for effects of copy number variation, and while nothing was significant, a duplication in CHRNA7 appears interesting enough to warrant further investigation.
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Affiliation(s)
- Erin L Heinzen
- Institute for Genome Sciences & Policy, Center for Human Genome Variation, Duke University Medical Center, Durham, NC 27708, USA.
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Stereoselective binding of chiral ligands to single nucleotide polymorphisms of the human organic cation transporter-1 determined using cellular membrane affinity chromatography. Anal Biochem 2010; 401:148-53. [PMID: 20206116 DOI: 10.1016/j.ab.2010.02.034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Revised: 02/24/2010] [Accepted: 02/26/2010] [Indexed: 11/23/2022]
Abstract
Membranes from stably transfected cell lines that express two point mutations of the human organic cation transporter-1 (hOCT1), R488M and G465R, have been immobilized on the immobilized artificial membrane (IAM) liquid chromatographic stationary phase to form two cellular membrane affinity chromatography (CMAC) columns, CMAC(hOCT1(G465R)) and CMAC(hOCT1(R488M)). Columns were created using both stationary phases, and frontal displacement chromatography experiments were conducted using [(3)H] MMP(+) (1-methyl-4-phenylpyridinium) as the marker ligand and various displacers, including the single enantiomers of verapamil, fenoterol, and isoproterenol. The chromatographic data obtained were used to refine a previously developed pharmacophore for hOCT1.
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Bencherif M, Lippiello PM. Alpha7 neuronal nicotinic receptors: the missing link to understanding Alzheimer's etiopathology? Med Hypotheses 2009; 74:281-5. [PMID: 19800174 DOI: 10.1016/j.mehy.2009.09.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Accepted: 09/07/2009] [Indexed: 11/27/2022]
Abstract
Evidence supports the premise that alpha7 nicotinic acetylcholine receptors in the central nervous system, sometimes referred to as neuronal nicotinic receptors (NNRs), play a central role in the development of Alzheimer's disease (AD) pathophysiology. Moreover, these receptors may represent the key to unifying aspects of the cholinergic hypothesis of AD with many of the apparently disparate mechanisms such as beta-amyloid deposition, tau hyperphosphorylation, and ApoE4 abnormalities variously proposed to underlie the progression of the disease. We hypothesize that neuronal degeneration in incipient AD is the result of coincident events involving, at their core, deficits in alpha7 NNR function. The resulting hypocholinergic tone could potentially have serious consequences since alpha7 NNRs are known to modulate fundamental pathways involved in cell survival such as JAK2-STAT3. This hypothesis predicts that any factors that compromise alpha7 function have the potential to negatively impact neuronal viability. For example, such factors could include deficits in the primary neurotransmitter acetylcholine (ACh), underactivity of normal cognitive processes that stimulate alpha7 NNRs (i.e., use-dependency), or the reported binding of beta-amyloid and ApoE4 to alpha7 NNRs, all of which could effectively decouple the receptors from key pro-survival pathways. Since these pathways are known to negatively modulate GSK-3beta, which regulates tau phosphorylation, downstream effects such as tau hyperphosphorylation would be expected to arise. Conversely, the maintenance of normal alpha7 NNR activity by adequate levels of ACh or other NNR agonists would be expected to support normal cholinergic tone, prevent the binding of beta-amyloid and ApoE4 and preserve the integrity of the neurons. We therefore propose that decreased cholinergic tone is at the apex of AD pathophysiology, with factors such as beta-amyloid and ApoE4 playing a contributory role rather that a causal one and hyperphosphorylation of tau representing a detector of concomitant hypocholinergic tone and beta-amyloid deposition. Thus the convergence of beta-amyloid deposition and/or ApoE4 binding and co-localization with alpha7 NNRs, which are favored under conditions of low cholinergic tone, and the downstream cascade of tau hyperphosphorylation through disinhibition of GSK-3beta appear to explain and reconcile many of the discordant findings in this very active area of CNS research.
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Affiliation(s)
- Merouane Bencherif
- Preclinical Research, Targacept, Inc., Suite 300, Winston-Salem, NC 27101-4165, USA.
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Dome P, Lazary J, Kalapos MP, Rihmer Z. Smoking, nicotine and neuropsychiatric disorders. Neurosci Biobehav Rev 2009; 34:295-342. [PMID: 19665479 DOI: 10.1016/j.neubiorev.2009.07.013] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 07/23/2009] [Accepted: 07/30/2009] [Indexed: 12/20/2022]
Abstract
Tobacco smoking is an extremely addictive and harmful form of nicotine (NIC) consumption, but unfortunately also the most prevalent. Although disproportionately high frequencies of smoking and its health consequences among psychiatric patients are widely known, the neurobiological background of this epidemiological association is still obscure. The diverse neuroactive effects of NIC and some other major tobacco smoke constituents in the central nervous system may underlie this association. This present paper summarizes the pharmacology of NIC and its receptors (nAChR) based on a systematic review of the literature. The role of the brain's reward system(s) in NIC addiction and the results of functional and structural neuroimaging studies on smoking-related states and behaviors (i.e. dependence, craving, withdrawal) are also discussed. In addition, the epidemiological, neurobiological, and genetic aspects of smoking in several specific neuropsychiatric disorders are reviewed and the clinical relevance of smoking in these disease states addressed.
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Affiliation(s)
- Peter Dome
- Department of Clinical and Theoretical Mental Health, Kutvolgyi Clinical Center, Semmelweis University, Faculty of Medicine, Kutvolgyi ut 4, 1125 Budapest, Hungary.
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Wang J, Papke RL, Horenstein NA. Synthesis of H-bonding probes of alpha7 nAChR agonist selectivity. Bioorg Med Chem Lett 2009; 19:474-6. [PMID: 19081250 PMCID: PMC2639621 DOI: 10.1016/j.bmcl.2008.11.044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Revised: 11/08/2008] [Accepted: 11/12/2008] [Indexed: 01/23/2023]
Abstract
The alpha7 subtype of the nicotinic acetylcholine receptor (nAChR) is the target of studies aimed at identifying features that will lead to the development of selective therapeutics. Five arylidine anabaseines, three with pyridine rings and two with the pyrrole rings, were synthesized in 35-65% yield via aldol condensation. The compounds are homologs of benzylidine anabaseine and were chosen for synthesis because they provide either a hydrogen bond acceptor (pyridines) or hydrogen bond donor (pyrroles) that may interact with the receptor within the benzylidine selectivity motif. Initial analysis of the new compounds at 100 microM concentration reveal that the two pyrrole anabaseines are good partial agonists of the alpha7 nAChR, having 40% of the efficacy of ACh, efficacy comparable to 4OH-GTS-21, and dramatically enhanced efficacy relative to the 2- and 4-pyridinyl compounds. The pyrrole compounds were confirmed to be alpha7 selective, displaying preference for this receptor over muscle and heteromeric neuronal receptor subtypes.
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Affiliation(s)
- Jingyi Wang
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, FL 32611-7200, USA
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Abstract
Gene expression changes in neuropsychiatric and neurodegenerative disorders, and gene responses to therapeutic drugs, provide new ways to identify central nervous system (CNS) targets for drug discovery. This review summarizes gene and pathway targets replicated in expression profiling of human postmortem brain, animal models, and cell culture studies. Analysis of isolated human neurons implicates targets for Alzheimer's disease and the cognitive decline associated with normal aging and mild cognitive impairment. In addition to tau, amyloid-beta precursor protein, and amyloid-beta peptides (Abeta), these targets include all three high-affinity neurotrophin receptors and the fibroblast growth factor (FGF) system, synapse markers, glutamate receptors (GluRs) and transporters, and dopamine (DA) receptors, particularly the D2 subtype. Gene-based candidates for Parkinson's disease (PD) include the ubiquitin-proteosome system, scavengers of reactive oxygen species, brain-derived neurotrophic factor (BDNF), its receptor, TrkB, and downstream target early growth response 1, Nurr-1, and signaling through protein kinase C and RAS pathways. Increasing variability and decreases in brain mRNA production from middle age to old age suggest that cognitive impairments during normal aging may be addressed by drugs that restore antioxidant, DNA repair, and synaptic functions including those of DA to levels of younger adults. Studies in schizophrenia identify robust decreases in genes for GABA function, including glutamic acid decarboxylase, HINT1, glutamate transport and GluRs, BDNF and TrkB, numerous 14-3-3 protein family members, and decreases in genes for CNS synaptic and metabolic functions, particularly glycolysis and ATP generation. Many of these metabolic genes are increased by insulin and muscarinic agonism, both of which are therapeutic in psychosis. Differential genomic signals are relatively sparse in bipolar disorder, but include deficiencies in the expression of 14-3-3 protein members, implicating these chaperone proteins and the neurotransmitter pathways they support as possible drug targets. Brains from persons with major depressive disorder reveal decreased expression for genes in glutamate transport and metabolism, neurotrophic signaling (eg, FGF, BDNF and VGF), and MAP kinase pathways. Increases in these pathways in the brains of animals exposed to electroconvulsive shock and antidepressant treatments identify neurotrophic and angiogenic growth factors and second messenger stimulation as therapeutic approaches for the treatment of depression.
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Decker MW, Gopalakrishnan M, Meyer MD. The potential of neuronal nicotinic acetylcholine receptor agonists for treating CNS conditions. Expert Opin Drug Discov 2008; 3:1027-40. [DOI: 10.1517/17460441.3.9.1027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Todd S, McKnight AJ, Liu WW, Carson R, Heggarty S, McGuinness B, Irvine GB, Craig D, Passmore AP, Johnston JA. BACE1 Polymorphisms Do Not Influence Platelet Membrane β-secretase Activity or Genetic Susceptibility for Alzheimer’s Disease in the Northern Irish Population. Neuromolecular Med 2008; 10:368-76. [DOI: 10.1007/s12017-008-8045-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2008] [Accepted: 06/13/2008] [Indexed: 11/30/2022]
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