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Donat CK, Hansen HH, Hansen HD, Mease RC, Horti AG, Pomper MG, L’Estrade ET, Herth MM, Peters D, Knudsen GM, Mikkelsen JD. In Vitro and In Vivo Characterization of Dibenzothiophene Derivatives [ 125I]Iodo-ASEM and [ 18F]ASEM as Radiotracers of Homo- and Heteromeric α7 Nicotinic Acetylcholine Receptors. Molecules 2020; 25:molecules25061425. [PMID: 32245032 PMCID: PMC7144377 DOI: 10.3390/molecules25061425] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/25/2020] [Accepted: 02/27/2020] [Indexed: 12/18/2022] Open
Abstract
The α7 nicotinic acetylcholine receptor (α7 nAChR) is involved in several cognitive and physiologic processes; its expression levels and patterns change in neurologic and psychiatric diseases, such as schizophrenia and Alzheimer’s disease, which makes it a relevant drug target. Development of selective radioligands is important for defining binding properties and occupancy of novel molecules targeting the receptor. We tested the in vitro binding properties of [125I]Iodo-ASEM [(3-(1,4-diazabycyclo[3.2.2]nonan-4-yl)-6-(125I-iododibenzo[b,d]thiopentene 5,5-dioxide)] in the mouse, rat and pig brain using autoradiography. The in vivo binding properties of [18F]ASEM were investigated using positron emission tomography (PET) in the pig brain. [125I]Iodo-ASEM showed specific and displaceable high affinity (~1 nM) binding in mouse, rat, and pig brain. Binding pattern overlapped with [125I]α-bungarotoxin, specific binding was absent in α7 nAChR gene-deficient mice and binding was blocked by a range of α7 nAChR orthosteric modulators in an affinity-dependent order in the pig brain. Interestingly, relative to the wild-type, binding in β2 nAChR gene-deficient mice was lower for [125I]Iodo-ASEM (58% ± 2.7%) than [125I]α-bungarotoxin (23% ± 0.2%), potentially indicating different binding properties to heteromeric α7β2 nAChR. [18F]ASEM PET in the pig showed high brain uptake and reversible tracer kinetics with a similar spatial distribution as previously reported for α7 nAChR. Blocking with SSR-180,711 resulted in a significant decrease in [18F]ASEM binding. Our findings indicate that [125I]Iodo-ASEM allows sensitive and selective imaging of α7 nAChR in vitro, with better signal-to-noise ratio than previous tracers. Preliminary data of [18F]ASEM in the pig brain demonstrated principal suitable kinetic properties for in vivo quantification of α7 nAChR, comparable to previously published data.
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Affiliation(s)
- Cornelius K. Donat
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
- Department of Brain Sciences, Imperial College London, London W12 0 LS, UK
- Correspondence: (C.K.D.); (J.D.M.); Tel.: +45-40205378 (J.D.M)
| | - Henrik H. Hansen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
| | - Hanne D. Hansen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
| | - Ronnie C. Mease
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (R.C.M.); (A.G.H.); (M.G.P.)
| | - Andrew G. Horti
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (R.C.M.); (A.G.H.); (M.G.P.)
| | - Martin G. Pomper
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (R.C.M.); (A.G.H.); (M.G.P.)
| | - Elina T. L’Estrade
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 162, 2100 Copenhagen, Denmark;
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Matthias M. Herth
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 162, 2100 Copenhagen, Denmark;
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | | | - Gitte M. Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
| | - Jens D. Mikkelsen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
- Correspondence: (C.K.D.); (J.D.M.); Tel.: +45-40205378 (J.D.M)
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Hirano T, Minagawa S, Furusawa Y, Yunoki T, Ikenaka Y, Yokoyama T, Hoshi N, Tabuchi Y. Growth and neurite stimulating effects of the neonicotinoid pesticide clothianidin on human neuroblastoma SH-SY5Y cells. Toxicol Appl Pharmacol 2019; 383:114777. [PMID: 31626844 DOI: 10.1016/j.taap.2019.114777] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 10/03/2019] [Accepted: 10/05/2019] [Indexed: 10/25/2022]
Abstract
Neonicotinoids are one of most widely used pesticides targeting nicotinic acetylcholine receptors (nAChRs) of insects. Recent epidemiological evidence revealed increasing amounts of neonicotinoids detected in human samples, raising the critical question of whether neonicotinoids affect human health. We investigated the effects of a neonicotinoid pesticide clothianidin (CTD) on human neuroblastoma SH-SY5Y cells as in vitro models of human neuronal cells. Cellular and functional effects of micromolar doses of CTD were evaluated by changes in cell growth, intracellular signaling activities and gene expression profiles. We examined further the effects of CTD on neuronal differentiation by measuring neurite outgrowth. Exposure to CTD (1-100 μM) significantly increased the number of cells within 24 h of culture. The nAChRs antagonists, mecamylamine and SR16584, inhibited this effect, suggesting human α3β4 nAChRs could be targets of neonicotinoids. We observed a transient intracellular calcium influx and increased phosphorylation of extracellular signal-regulated kinase 1/2 shortly after exposure to CTD. Transcriptome analysis revealed that CTD down-regulated genes involved in neuronal function (e.g., formation of filopodia and calcium ion influx) and morphology (e.g., axon guidance signaling and cytoskeleton signaling); these changes were reflected by a finding of increased neurite length during neuronal differentiation. These findings provide novel insight into the potential risks of neonicotinoids to the human nervous system.
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Affiliation(s)
- Tetsushi Hirano
- Life Science Research Center, University of Toyama, Toyama, Japan.
| | - Satsuki Minagawa
- Life Science Research Center, University of Toyama, Toyama, Japan
| | - Yukihiro Furusawa
- Department of Liberal Arts and Sciences, Toyama Prefectural University, Toyama, Japan
| | - Tatsuya Yunoki
- Department of Ophthalmology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Yoshinori Ikenaka
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, Japan; Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Toshifumi Yokoyama
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Nobuhiko Hoshi
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Yoshiaki Tabuchi
- Life Science Research Center, University of Toyama, Toyama, Japan
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Britvin SN, Rumyantsev AM. Crystal structure of (1 S,4 S)-2,5-diazo-niabi-cyclo[2.2.1]heptane dibromide. Acta Crystallogr E Crystallogr Commun 2017; 73:1861-1865. [PMID: 29250403 PMCID: PMC5730240 DOI: 10.1107/s2056989017015870] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 10/31/2017] [Indexed: 11/10/2022]
Abstract
The cage of 2,5-di-aza-bicyclo-[2.2.1]heptane is frequently employed in synthetic chemistry as a rigid bicyclic counterpart of the piperazine ring. The 2,5-di-azabicyclo-[2.2.1]heptane scaffold is incorporated into a variety of compounds having pharmacological and catalytic applications. The unsubstituted parent ring of the system, 2,5-di-aza-bicyclo-[2.2.1]heptane itself, has not been structurally characterized. We herein report on the mol-ecular structure of the parent ring in (1S,4S)-2,5-diazo-niabi-cyclo-[2.2.1]heptane dibromide, C5H12N22+·2Br-. The asymmetric unit contains two crystallographically independent cages of 2,5-di-aza-bicyclo-[2.2.1]heptane. Each cage is protonated at the two nitro-gen sites. The overall charge balance is maintained by four crystallographically independent bromide ions. In the crystal, the components of the structure are linked via a complex three-dimensional network of N-H⋯Br hydrogen bonds.
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Affiliation(s)
- Sergey N. Britvin
- Department of Crystallography, Saint-Petersburg State University, Universitetskaya Nab. 7/9, 199034 St. Petersburg, Russian Federation
| | - Andrey M. Rumyantsev
- Department of Genetics and Biotechnology, Saint-Petersburg State University, Universitetskaya Nab. 7/9, 199034 St. Petersburg, Russian Federation
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Newcombe J, Chatzidaki A, Sheppard TD, Topf M, Millar NS. Diversity of Nicotinic Acetylcholine Receptor Positive Allosteric Modulators Revealed by Mutagenesis and a Revised Structural Model. Mol Pharmacol 2017; 93:128-140. [PMID: 29196491 PMCID: PMC5767682 DOI: 10.1124/mol.117.110551] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 11/30/2017] [Indexed: 01/26/2023] Open
Abstract
By combining electrophysiological and computational approaches we have examined a series of positive allosteric modulators (PAMs) acting on the human α7 nicotinic acetylcholine receptor (nAChR). Electrophysiological studies have focused on three α7-selective PAMs (A-867744, TBS-516, and TQS) that display similar effects on wild-type α7 nAChRs. In addition to potentiating agonist-evoked responses, all three compounds reduce receptor desensitization and, consequently, are classed as type II PAMs. Despite having similar effects on wild-type receptors, A-867744 was found to have profoundly differing effects on mutated receptors compared with TBS-516 and TQS, a finding that is consistent with previous studies indicating that A-867744 may have a different mechanism of action compare with other α7-selective type II PAMs. Due to evidence that these PAMs bind within the α7 nAChR transmembrane region, we generated and validated new structural models of α7. Importantly, we have corrected a previously identified error in the transmembrane region of the original cryo–electron microscopy Torpedo model; the only pentameric ligand-gated ion channel imaged in a native lipid membrane. Real-space refinement was used to generate closed and open conformations on which the α7 models were based. Consensus docking with an extended series of PAMs with chemical similarity to A-867744, TBS-516, and TQS suggests that all bind to a broadly similar intersubunit transmembrane site. However, differences in the predicted binding of A-867744, compared with TBS-516 and TQS, may help to explain the distinct functional effects of A-867744. Thus, our revised structural models may provide a useful tool for interpreting functional effects of PAMs.
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Affiliation(s)
- Joseph Newcombe
- Departments of Chemistry (J.N., T.D.S.) and Neuroscience, Physiology and Pharmacology (A.C., N.S.M.), University College London, London, United Kingdom; and Institute of Structural and Molecular Biology, Birkbeck, University of London, London, United Kingdom (J.N., M.T.)
| | - Anna Chatzidaki
- Departments of Chemistry (J.N., T.D.S.) and Neuroscience, Physiology and Pharmacology (A.C., N.S.M.), University College London, London, United Kingdom; and Institute of Structural and Molecular Biology, Birkbeck, University of London, London, United Kingdom (J.N., M.T.)
| | - Tom D Sheppard
- Departments of Chemistry (J.N., T.D.S.) and Neuroscience, Physiology and Pharmacology (A.C., N.S.M.), University College London, London, United Kingdom; and Institute of Structural and Molecular Biology, Birkbeck, University of London, London, United Kingdom (J.N., M.T.)
| | - Maya Topf
- Departments of Chemistry (J.N., T.D.S.) and Neuroscience, Physiology and Pharmacology (A.C., N.S.M.), University College London, London, United Kingdom; and Institute of Structural and Molecular Biology, Birkbeck, University of London, London, United Kingdom (J.N., M.T.)
| | - Neil S Millar
- Departments of Chemistry (J.N., T.D.S.) and Neuroscience, Physiology and Pharmacology (A.C., N.S.M.), University College London, London, United Kingdom; and Institute of Structural and Molecular Biology, Birkbeck, University of London, London, United Kingdom (J.N., M.T.)
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Pieschl RL, Miller R, Jones KM, Post-Munson DJ, Chen P, Newberry K, Benitex Y, Molski T, Morgan D, McDonald IM, Macor JE, Olson RE, Asaka Y, Digavalli S, Easton A, Herrington J, Westphal RS, Lodge NJ, Zaczek R, Bristow LJ, Li YW. Effects of BMS-902483, an α7 nicotinic acetylcholine receptor partial agonist, on cognition and sensory gating in relation to receptor occupancy in rodents. Eur J Pharmacol 2017; 807:1-11. [PMID: 28438647 DOI: 10.1016/j.ejphar.2017.04.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Revised: 04/13/2017] [Accepted: 04/19/2017] [Indexed: 10/19/2022]
Abstract
The α7 nicotinic acetylcholine receptor is thought to play an important role in human cognition. Here we describe the in vivo effects of BMS-902483, a selective potent α7 nicotinic acetylcholine receptor partial agonist, in relationship to α7 nicotinic acetylcholine receptor occupancy. BMS-902483 has low nanomolar affinity for rat and human α7 nicotinic acetylcholine receptors and elicits currents in cells expressing human or rat α7 nicotinic acetylcholine receptors that are about 60% of the maximal acetylcholine response. BMS-902483 improved 24h novel object recognition memory in mice with a minimal effective dose (MED) of 0.1mg/kg and reversed MK-801-induced deficits in a rat attentional set-shifting model of executive function with an MED of 3mg/kg. Enhancement of novel object recognition was blocked by the silent α7 nicotinic acetylcholine receptor agonist, NS6740, demonstrating that activity of BMS-902483 was mediated by α7 nicotinic acetylcholine receptors. BMS-902483 also reversed ketamine-induced deficits in auditory gating in rats, and enhanced ex vivo hippocampal long-term potentiation examined 24h after dosing in mice. Results from an ex vivo brain homogenate binding assay showed that α7 receptor occupancy ranged from 64% (novel object recognition) to ~90% (set shift and gating) at the MED for behavioral and sensory processing effects of BMS-902483.
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Affiliation(s)
- Rick L Pieschl
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Regina Miller
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Kelli M Jones
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Debra J Post-Munson
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Ping Chen
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Kimberly Newberry
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Yulia Benitex
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Thaddeus Molski
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Daniel Morgan
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Ivar M McDonald
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - John E Macor
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Richard E Olson
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Yukiko Asaka
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Siva Digavalli
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Amy Easton
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - James Herrington
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Ryan S Westphal
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Nicholas J Lodge
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Robert Zaczek
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Linda J Bristow
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA
| | - Yu-Wen Li
- Bristol-Myers Squibb Company, Department of Neuroscience, 5 Research Parkway, Wallingford, CT 06492, USA.
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Potasiewicz A, Nikiforuk A, Hołuj M, Popik P. Stimulation of nicotinic acetylcholine alpha7 receptors rescue schizophrenia-like cognitive impairments in rats. J Psychopharmacol 2017; 31:260-271. [PMID: 28168926 DOI: 10.1177/0269881116675509] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Alpha7 nicotinic acetylcholine receptor (α7 nAChR) dysfunction plays an important role in schizophrenia. Positive allosteric modulators of α7 nAChR have emerged as a promising therapeutic approach to manage cognitive deficits that are inadequately treated in schizophrenic patients. The aim of the present study was to evaluate the ability of type I (CCMI) and type II (PNU120596) α7 nAChR positive allosteric modulators to counteract MK-801-induced cognitive and sensorimotor gating deficits. The activity of these compounds was compared with the action of the α7 nAChR agonist A582941. CCMI, PNU120596 and A582941 reversed the sensorimotor gating impairment evoked by MK-801 based on the prepulse inhibition of the startle response. Additionally, no MK-801-evoked working memory deficits were observed with α7 nAChR ligand pretreatment as assessed in a discrete paired-trial delayed alternation task. However, these compounds did not affect the rats' attentional performances in the five-choice serial reaction time test. The α7 nAChR agents demonstrated a beneficial effect on sensorimotor gating and some aspects of cognition tested in a rat model of schizophrenia. Therefore, these results support the use of α7 nAChR positive allosteric modulators as a potential treatment strategy in schizophrenia.
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Affiliation(s)
- Agnieszka Potasiewicz
- 1 Department of Behavioural Neuroscience and Drug Development, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Agnieszka Nikiforuk
- 1 Department of Behavioural Neuroscience and Drug Development, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Małgorzata Hołuj
- 1 Department of Behavioural Neuroscience and Drug Development, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Piotr Popik
- 1 Department of Behavioural Neuroscience and Drug Development, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland.,2 Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
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Post-Munson DJ, Pieschl RL, Molski TF, Graef JD, Hendricson AW, Knox RJ, McDonald IM, Olson RE, Macor JE, Weed MR, Bristow LJ, Kiss L, Ahlijanian MK, Herrington J. B-973, a novel piperazine positive allosteric modulator of the α7 nicotinic acetylcholine receptor. Eur J Pharmacol 2017; 799:16-25. [PMID: 28132910 DOI: 10.1016/j.ejphar.2017.01.037] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 01/23/2017] [Accepted: 01/25/2017] [Indexed: 11/18/2022]
Abstract
The alpha7 (α7) nicotinic acetylcholine receptor is a therapeutic target for cognitive disorders. Here we describe 3-(3,4-difluorophenyl)-N-(1-(6-(4-(pyridin-2-yl)piperazin-1-yl)pyrazin-2-yl)ethyl)propanamide (B-973), a novel piperazine-containing molecule that acts as a positive allosteric modulator of the α7 receptor. We characterize the action of B-973 on the α7 receptor using electrophysiology and radioligand binding. At 0.1mM acetylcholine, 1μM B-973 potentiated peak acetylcholine-induced currents 6-fold relative to maximal acetylcholine (3mM) and slowed channel desensitization, resulting in a 6900-fold increase in charge transfer. The EC50 of B-973 was approximately 0.3μM at acetylcholine concentrations ranging from 0.03 to 3mM. At a concentration of 1μM, B-973 shifted the acetylcholine EC50 of peak currents from 0.30mM in control to 0.007mM. B-973 slowed channel deactivation upon acetylcholine removal (τ=50s) and increased the affinity of the α7 agonist [3H]A-585539. In the absence of exogenously added acetylcholine, application of B-973 at concentrations >1μM induced large methyllycaconitine-sensitive currents, suggesting B-973 can function as an Ago-PAM at high concentrations. B-973 will be a useful probe for investigating the biological consequences of increasing α7 receptor activity through allosteric modulation.
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Affiliation(s)
- Debra J Post-Munson
- Discovery Biology, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - Rick L Pieschl
- Discovery Biology, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - Thaddeus F Molski
- Discovery Biology, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - John D Graef
- Discovery Biology, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - Adam W Hendricson
- Lead Discovery and Optimization, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - Ronald J Knox
- Lead Discovery and Optimization, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - Ivar M McDonald
- Discovery Chemistry, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - Richard E Olson
- Discovery Chemistry, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - John E Macor
- Discovery Chemistry, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - Michael R Weed
- Discovery Biology, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - Linda J Bristow
- Discovery Biology, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - Laszlo Kiss
- Lead Discovery and Optimization, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - Michael K Ahlijanian
- Discovery Biology, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA
| | - James Herrington
- Discovery Biology, Bristol-Myers Squibb, Inc., 5 Research Parkway, Wallingford, CT 06492 USA.
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PET imaging of α 7 nicotinic acetylcholine receptors: a comparative study of [ 18F]ASEM and [ 18F]DBT-10 in nonhuman primates, and further evaluation of [ 18F]ASEM in humans. Eur J Nucl Med Mol Imaging 2017; 44:1042-1050. [PMID: 28120003 DOI: 10.1007/s00259-017-3621-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 12/20/2016] [Indexed: 10/20/2022]
Abstract
PURPOSE The α7 nicotinic acetylcholine receptor (nAChR) is implicated in many neuropsychiatric disorders, making it an important target for positron emission tomography (PET) imaging. The first aim of this work was to compare two α7 nAChRs PET radioligands, [18F]ASEM (3-(1,4-diazabicyclo[3.2.2]nonan-4-yl)-6-([18F]fluorodibenzo[b,d]thiophene 5,5-dioxide) and [18F]DBT-10 (7-(1,4-diazabicyclo[3.2.2]nonan-4-yl)-2-([18F]fluorodibenzo[b,d]thiophene 5,5-dioxide), in nonhuman primates. The second aim was to assess further the quantification and test-retest variability of [18F]ASEM in humans. METHODS PET scans with high specific activity [18F]ASEM or [18F]DBT-10 were acquired in three rhesus monkeys (one male, two female), and the kinetic properties of these radiotracers were compared. Additional [18F]ASEM PET scans with blocking doses of nicotine, varenicline, and cold ASEM were acquired separately in two animals. Next, six human subjects (five male, one female) were imaged with [18F]ASEM PET for 180 min, and arterial sampling was used to measure the parent input function. Different modeling approaches were compared to identify the optimal analysis method and scan duration for quantification of [18F]ASEM distribution volume (V T). In addition, retest scans were acquired in four subjects (three male, one female), and the test-retest variability of V T was assessed. RESULTS In the rhesus monkey brain [18F]ASEM and [18F]DBT-10 exhibited highly similar kinetic profiles. Dose-dependent blockade of [18F]ASEM binding was observed, while administration of either nicotine or varenicline did not change [18F]ASEM V T. [18F]ASEM was selected for further validation because it has been used in humans. Accurate quantification of [18F]ASEM V T in humans was achieved using multilinear analysis with at least 90 min of data acquisition, resulting in V T values ranging from 19.6 ± 2.5 mL/cm3 in cerebellum to 25.9 ± 2.9 mL/cm3 in thalamus. Test-retest variability of V T was 11.7 ± 9.8%. CONCLUSIONS These results confirm [18F]ASEM as a suitable radiotracer for the imaging and quantification of α7 nAChRs in humans.
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The Novel, Nicotinic Alpha7 Receptor Partial Agonist, BMS-933043, Improves Cognition and Sensory Processing in Preclinical Models of Schizophrenia. PLoS One 2016; 11:e0159996. [PMID: 27467081 PMCID: PMC4965148 DOI: 10.1371/journal.pone.0159996] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 07/12/2016] [Indexed: 01/01/2023] Open
Abstract
The development of alpha7 nicotinic acetylcholine receptor agonists is considered a promising approach for the treatment of cognitive symptoms in schizophrenia patients. In the present studies we characterized the novel agent, (2R)-N-(6-(1H-imidazol-1-yl)-4-pyrimidinyl)-4'H-spiro[4-azabicyclo[2.2.2]octane-2,5'-[1,3]oxazol]-2'-amine (BMS-933043), in vitro and in rodent models of schizophrenia-like deficits in cognition and sensory processing. BMS-933043 showed potent binding affinity to native rat (Ki = 3.3 nM) and recombinant human alpha7 nicotinic acetylcholine receptors (Ki = 8.1 nM) and agonist activity in a calcium fluorescence assay (EC50 = 23.4 nM) and whole cell voltage clamp electrophysiology (EC50 = 0.14 micromolar (rat) and 0.29 micromolar (human)). BMS-933043 exhibited a partial agonist profile relative to acetylcholine; the relative efficacy for net charge crossing the cell membrane was 67% and 78% at rat and human alpha7 nicotinic acetylcholine receptors respectively. BMS-933043 showed no agonist or antagonist activity at other nicotinic acetylcholine receptor subtypes and was at least 300 fold weaker at binding to and antagonizing human 5-HT3A receptors (Ki = 2,451 nM; IC50 = 8,066 nM). BMS-933043 treatment i) improved 24 hour novel object recognition memory in mice (0.1-10 mg/kg, sc), ii) reversed MK-801-induced deficits in Y maze performance in mice (1-10 mg/kg, sc) and set shift performance in rats (1-10 mg/kg, po) and iii) reduced the number of trials required to complete the extradimensional shift discrimination in neonatal PCP treated rats performing the intra-dimensional/extradimensional set shifting task (0.1-3 mg/kg, po). BMS-933043 also improved auditory gating (0.56-3 mg/kg, sc) and mismatch negativity (0.03-3 mg/kg, sc) in rats treated with S(+)ketamine or neonatal phencyclidine respectively. Given this favorable preclinical profile BMS-933043 was selected for further development to support clinical evaluation in humans.
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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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Wallace TL, Bertrand D. Neuronal α7 Nicotinic Receptors as a Target for the Treatment of Schizophrenia. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2015; 124:79-111. [PMID: 26472526 DOI: 10.1016/bs.irn.2015.08.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Schizophrenia is a lifelong disease, the burden of which is often underestimated. Characterized by positive (e.g., hallucinations) and negative (e.g., avolition, amotivation) symptoms, schizophrenia is also accompanied with profound impairments in cognitive function that progress throughout the development of the disease. Although treatment with antipsychotic medications can effectively dampen some of the positive symptoms, these medications largely fail to reverse cognitive deficits or to mitigate negative symptoms. With a worldwide prevalence of approximately 1%, schizophrenia remains a large unmet medical need that stands to benefit greatly from (1) continued research to better understand the biological underpinnings of the disease and (2) the targeted development of novel therapeutics to improve the lives of those affected individuals. Improvements in our understanding of the neuronal networks associated with schizophrenia as well as progress in identifying genetic risk factors and environmental conditions that may predispose individuals to developing the disease are advancing new strategies to study and treat it. Herein, we review the evidence that supports the role of α7 nicotinic acetylcholine receptors in the central nervous system and why these receptors constitute a promising target to treat some of the prominent symptoms of schizophrenia.
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Tang JS, Xie BX, Bian XL, Xue Y, Wei NN, Zhou JH, Hao YC, Li G, Zhang LR, Wang KW. Identification and in vitro pharmacological characterization of a novel and selective α7 nicotinic acetylcholine receptor agonist, Br-IQ17B. Acta Pharmacol Sin 2015; 36:800-12. [PMID: 25948478 PMCID: PMC4648113 DOI: 10.1038/aps.2015.9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 03/03/2015] [Indexed: 12/14/2022] Open
Abstract
Aim: Alpha7-nicotinic acetylcholine receptor (α7 nAChR) is a ligand-gated Ca2+-permeable ion channel implicated in cognition and neuropsychiatric disorders. Activation of α7 nAChR improves learning, memory, and sensory gating in animal models. To identify novel α7 nAChR agonists, we synthesized a series of small molecules and characterized a representative compound, Br-IQ17B, N-[(3R)-1-azabicyclo[2,2,2]oct-3-yl]-5-bromoindolizine-2-carboxamide, which specifically activates α7 nAChR. Methods: Two-electrode voltage clamp (TEVC) recordings were primarily used for screening in Xenopus oocytes expressing human α7 nAChR. Assays, including radioisotope ligand binding, Western blots, whole-cell recordings of hippocampal culture neurons, and spontaneous IPSC recordings of brain slices, were also utilized to evaluate and confirm the specific activation of α7 nAChR by Br-IQ17B. Results: Br-IQ17B potently activates α7 nAChR with an EC50 of 1.8±0.2 μmol/L. Br-IQ17B is selective over other subtypes such as α4β2 and α3β4, but it blocks 5-HT3A receptors. Br-IQ17B displaced binding of the α7 blocker [3H]-MLA to hippocampal crude membranes with a Ki of 14.9±3.2 nmol/L. In hippocampal neurons, Br-IQ17B evoked α7-like currents that were inhibited by MLA and enhanced in the presence of the α7 PAM PNU-120596. In brain slice recordings, Br-IQ17B enhanced GABAergic synaptic transmission in CA1 neurons. Mechanistically, Br-IQ17B increased ERK1/2 phosphorylation that was MLA-sensitive. Conclusion: We identified the novel, potent, and selective α7 agonist Br-IQ17B, which enhances synaptic transmission. Br-IQ17B may be a helpful tool to understand new aspects of α7 nAChR function, and it also has potential for being developed as therapy for schizophrenia and cognitive deficits.
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Beinat C, Banister SD, Herrera M, Law V, Kassiou M. The therapeutic potential of α7 nicotinic acetylcholine receptor (α7 nAChR) agonists for the treatment of the cognitive deficits associated with schizophrenia. CNS Drugs 2015; 29:529-42. [PMID: 26242477 DOI: 10.1007/s40263-015-0260-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Homomeric α7 nicotinic acetylcholine receptors (α7 nAChRs) have implications in the regulation of cognitive processes such as memory and attention, and have shown promise as a therapeutic target for the treatment of the cognitive deficits associated with schizophrenia. Multiple α7 nAChR agonists have entered human trials; however, unfavorable side effects and pharmacokinetic issues have hindered the development of a clinical α7 nAChR agonist. Currently, EVP-6124 is in phase III clinical trials, and several other α7 nAChR agonists (GTS-21 and AQW051) are in earlier stages of development. This review will summarize the recent advances and failures of α7 nAChR agonists in clinical trials for the treatment of the aforementioned pathology.
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Affiliation(s)
- Corinne Beinat
- Department of Radiology, Stanford University School of Medicine, Stanford, CA, 94305, USA
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Wu A, Li X, Xue Q, Liu Y, Lu X, Yan X, Zhang H. Radio synthesis and in vivo evaluation of two α7 nAChRs radioligands: [125I]CAIPE and [125I]IPPU. J Radioanal Nucl Chem 2015. [DOI: 10.1007/s10967-015-4235-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Magnussen JH, Ettrup A, Donat CK, Peters D, Pedersen MHF, Knudsen GM, Mikkelsen JD. Radiosynthesis and in vitro validation of (3)H-NS14492 as a novel high affinity alpha7 nicotinic receptor radioligand. Eur J Pharmacol 2015; 762:35-41. [PMID: 25941084 DOI: 10.1016/j.ejphar.2015.04.036] [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: 09/17/2014] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 11/30/2022]
Abstract
The neuronal α7 nicotinic acetylcholine receptor is a homo-pentameric ligand-gated ion channel that is a promising drug target for cognitive deficits in Alzheimer׳s disease and schizophrenia. We have previously described (11)C-NS14492 as a suitable agonist radioligand for in vivo positron emission tomography (PET) occupancy studies of the α7 nicotinic receptor in the pig brain. In order to investigate the utility of the same compound for in vitro studies, (3)H-NS14492 was synthesized and its binding properties were characterized using in vitro autoradiography and homogenate binding assays in pig frontal cortex. (3)H-NS14492 showed specific binding to α7 nicotinic receptors in autoradiography, revealing a dissociation constant (Kd) of 2.1±0.7nM and a maximum number of binding sites (Bmax) of 15.7±2.0fmol/mg tissue equivalent. Binding distribution was similar to that of another selective ligand (125)I-α-bungarotoxin ((125)I-BTX) in autoradiography, and unlabeled NS14492 displaced (125)I-BTX with an inhibition constant (Ki) of 23nM. (3)H-NS14492 bound to α7 nicotinic receptors in homogenized pig frontal cortex with a Kd of 0.8±0.3nM and a Bmax of 30.2±11.6fmol/mg protein. This binding assay further revealed the Ki rank order for a number of α7 nicotinic receptor agonists, and positive allosteric modulators (PAMs). Further, we saw increased binding of (3)H-NS14492 to pig frontal cortex membranes when co-incubated with PNU-120596, a type II PAM. Taken together, these findings show that (3)H-NS14492 is a useful new in vitro radioligand for the pig α7 nicotinic receptor.
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Affiliation(s)
- Janus H Magnussen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Anders Ettrup
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Cornelius K Donat
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | | | - Martin H F Pedersen
- The Hevesy Laboratory, DTU Nutech, The Technical University of Denmark, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Jens D Mikkelsen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
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Fan H, Gu R, Wei D. The α7 nAChR selective agonists as drug candidates for Alzheimer's disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 827:353-65. [PMID: 25387975 DOI: 10.1007/978-94-017-9245-5_21] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The nicotinic acetylcholine receptors (nAChRs) are ion channels distribute in the central or peripheral nervous system. They are receptors of the neurotransmitter acetylcholine and activation of them by agonists mediates synaptic transmission in the neuron and muscle contraction in the neuromuscular junction. Current studies reveal relationship between the nAChRs and the learning and memory as well as cognation deficit in various neurological disorders such as Alzheimer's disease, Parkinson's disease, schizophrenia and drug addiction. There are various subtypes in the nAChR family and the α7 nAChR is one of the most abundant subtypes in the brain. The α7 nAChR is significantly reduced in the patients of Alzheimer's disease and is believed to interact with the Aβ amyloid. Aβ amyloid is co-localized with α7 nAChR in the senile plaque and interaction between them induces neuron apoptosis and reduction of the α7 nAChR expression. Treatment with α7 agonist in vivo shows its neuron protective and procognation properties and significantly improves the learning and memory ability of the animal models. Therefore, the α7 nAChR agonists are excellent drug candidates for Alzheimer's disease and we summarized here the current agonists that have selectivity of the α7 nAChR over the other nAChR, introduced recent molecular modeling works trying to explain the molecular mechanism of their selectivity and described the design of novel allosteric modulators in our lab.
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Affiliation(s)
- Huaimeng Fan
- State Key Laboratory of Microbial Metabolism, College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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Alexander SPH, Benson HE, Faccenda E, Pawson AJ, Sharman JL, Spedding M, Peters JA, Harmar AJ. The Concise Guide to PHARMACOLOGY 2013/14: ligand-gated ion channels. Br J Pharmacol 2014; 170:1582-606. [PMID: 24528238 PMCID: PMC3892288 DOI: 10.1111/bph.12446] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The Concise Guide to PHARMACOLOGY 2013/14 provides concise overviews of the key properties of over 2000 human drug targets with their pharmacology, plus links to an open access knowledgebase of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. The full contents can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.12444/full. Ligand-gated ion channels are one of the seven major pharmacological targets into which the Guide is divided, with the others being G protein-coupled receptors, ion channels, catalytic receptors, nuclear hormone receptors, transporters and enzymes. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. A new landscape format has easy to use tables comparing related targets. It is a condensed version of material contemporary to late 2013, which is presented in greater detail and constantly updated on the website www.guidetopharmacology.org, superseding data presented in previous Guides to Receptors and Channels. It is produced in conjunction with NC-IUPHAR and provides the official IUPHAR classification and nomenclature for human drug targets, where appropriate. It consolidates information previously curated and displayed separately in IUPHAR-DB and the Guide to Receptors and Channels, providing a permanent, citable, point-in-time record that will survive database updates.
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Affiliation(s)
- Stephen P H Alexander
- School of Life Sciences, University of Nottingham Medical School, Nottingham, NG7 2UH, UK
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Gao Y, Kellar KJ, Yasuda RP, Tran T, Xiao Y, Dannals RF, Horti AG. Derivatives of dibenzothiophene for positron emission tomography imaging of α7-nicotinic acetylcholine receptors. J Med Chem 2013; 56:7574-89. [PMID: 24050653 DOI: 10.1021/jm401184f] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A new series of derivatives of 3-(1,4-diazabicyclo[3.2.2]nonan-4-yl)dibenzo[b,d]thiophene 5,5-dioxide with high binding affinities and selectivity for α7-nicotinic acetylcholine receptors (α7-nAChRs) (Ki = 0.4-20 nM) has been synthesized for positron emission tomography (PET) imaging of α7-nAChRs. Two radiolabeled members of the series [(18)F]7a (Ki = 0.4 nM) and [(18)F]7c (Ki = 1.3 nM) were synthesized. [(18)F]7a and [(18)F]7c readily entered the mouse brain and specifically labeled α7-nAChRs. The α7-nAChR selective ligand 1 (SSR180711) blocked the binding of [(18)F]7a in the mouse brain in a dose-dependent manner. The mouse blocking studies with non-α7-nAChR central nervous system drugs demonstrated that [(18)F]7a is highly α7-nAChR selective. In agreement with its binding affinity the binding potential of [(18)F]7a (BPND = 5.3-8.0) in control mice is superior to previous α7-nAChR PET radioligands. Thus, [(18)F]7a displays excellent imaging properties in mice and has been chosen for further evaluation as a potential PET radioligand for imaging of α7-nAChR in non-human primates.
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Affiliation(s)
- Yongjun Gao
- Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Nuclear Medicine, The Johns Hopkins University School of Medicine , 600 North Wolfe Street, Baltimore, Maryland 21287-0816, United States
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Virtual screening for alpha7 nicotinic acetylcholine receptor for treatment of Alzheimer's disease. J Mol Graph Model 2013; 39:98-107. [DOI: 10.1016/j.jmgm.2012.11.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 11/19/2012] [Accepted: 11/20/2012] [Indexed: 11/18/2022]
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21
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Nicotinic acetylcholine receptors: From basic science to therapeutics. Pharmacol Ther 2013; 137:22-54. [DOI: 10.1016/j.pharmthera.2012.08.012] [Citation(s) in RCA: 382] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Accepted: 08/20/2012] [Indexed: 12/14/2022]
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Ortiz NC, O'Neill HC, Marks MJ, Grady SR. Varenicline blocks β2*-nAChR-mediated response and activates β4*-nAChR-mediated responses in mice in vivo. Nicotine Tob Res 2012; 14:711-9. [PMID: 22241831 DOI: 10.1093/ntr/ntr284] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
INTRODUCTION The smoking cessation aid, varenicline, has higher affinity for the alpha4beta2-subtype of the nicotinic acetylcholine receptor (α4β2*-nAChR) than for other subtypes of nAChRs by in vitro assays. The mechanism of action of acute varenicline was studied in vivo to determine (a) subtype activation associated with physiological effects and (b) dose relationship as an antagonist of nicotine. METHODS Acute doses of saline, nicotine, and varenicline were given to mice, and locomotor depression and hypothermia were measured. Subunit null mutant mice as well as selective antagonists were used to study mode of action of varenicline as an agonist. Varenicline as an antagonist of nicotine was also investigated. RESULTS Varenicline evokes locomotor depression and hypothermia at higher doses than necessary for nicotine. Null mutation of the α7- or β2-nAChR subunit did not decrease the effectiveness of varenicline; however, null mutation of the β4 subunit significantly decreased the magnitude of the varenicline effect. Effects of the highest dose studied were blocked by mecamylamine (general nAChR antagonist) and partially antagonized by hexamethonium (largely peripheral nAChR antagonist). No significant block was seen with ondansetron antagonist of 5-hydroxytryptamine 3 receptor. Using a dose of nicotine selective for β2*-nAChR subtype effects with these tests, dose-dependent antagonism by varenicline was seen. Effective inhibitory doses were determined and appear to be in a range consistent with binding affinity or desensitization of β2*-nAChRs. CONCLUSIONS Varenicline acts as a functional antagonist of β2*-nAChRs, blocking certain effects of nicotine. At higher doses, varenicline is an agonist of β4*-nAChRs producing physiological changes in mice.
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Affiliation(s)
- Nick C Ortiz
- Institute for Behavioral Genetics, University of Colorado, Boulder, CO 80309, USA
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Scanio MJC, Shi L, Bunnelle WH, Anderson DJ, Helfrich RJ, Malysz J, Thorin-Hagene KK, Van Handel CE, Marsh KC, Lee CH, Gopalakrishnan M. Structure–Activity Studies of Diazabicyclo[3.3.0]octane-Substituted Pyrazines and Pyridines as Potent α4β2 Nicotinic Acetylcholine Receptor Ligands. J Med Chem 2011; 54:7678-92. [DOI: 10.1021/jm201045m] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marc J. C. Scanio
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
| | - Lei Shi
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
| | - William H. Bunnelle
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
| | - David J. Anderson
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
| | - Rosalind J. Helfrich
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
| | - John Malysz
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
| | - Kirsten K. Thorin-Hagene
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
| | - Ceclia E. Van Handel
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
| | - Kennan C. Marsh
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
| | - Chih-Hung Lee
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
| | - Murali Gopalakrishnan
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6117, United States
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Mazurov AA, Speake JD, Yohannes D. Discovery and development of α7 nicotinic acetylcholine receptor modulators. J Med Chem 2011; 54:7943-61. [PMID: 21919481 DOI: 10.1021/jm2007672] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anatoly A Mazurov
- Targacept, Inc, Winston-Salem, North Carolina 27101-4165, United States.
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Li J, Mathieu SL, Harris R, Ji J, Anderson DJ, Malysz J, Bunnelle WH, Waring JF, Marsh KC, Murtaza A, Olson LM, Gopalakrishnan M. Role of α7 nicotinic acetylcholine receptors in regulating tumor necrosis factor-α (TNF-α) as revealed by subtype selective agonists. J Neuroimmunol 2011; 239:37-43. [PMID: 21911260 DOI: 10.1016/j.jneuroim.2011.08.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2011] [Revised: 06/25/2011] [Accepted: 08/10/2011] [Indexed: 12/28/2022]
Abstract
Immunological responses to protect against excessive inflammation can be regulated by the central nervous system through the cholinergic anti-inflammatory pathway wherein acetylcholine released from vagus nerves can inhibit inflammatory cytokines. Although a role for the α7 nicotinic acetylcholine receptor (α7 nAChR) in mediating this pathway has been suggested, pharmacological modulation of the pathway by selective agonists remains to be further elucidated. In this study, the role of α7 nAChRs in the regulation of TNF-α release was investigated using high affinity and selective α7 nAChR agonists in mouse peritoneal macrophage and human whole blood in vitro, and in mouse serum in vivo. In mouse peritoneal macrophages, LPS-induced TNF-α release in vitro was inhibited by a selective α7 nAChR agonist, A-833834 (5-[6-(5-Methyl-hexahydro-pyrrolo[3,4-c]pyrrol-2-yl)-pyridazin-3-yl]-1H-indole), and that effect was attenuated by α7 nAChR antagonist methyllycaconitine. The inhibitory effect of A-833834 on LPS-induced TNF-α release was also observed in human whole blood in vitro. I.v. LPS-induced TNF-α release in mouse serum was attenuated following i.p. administration of A-833834. Similarly, i.v. LPS-induced TNF-α release in mouse serum was also attenuated following i.p. administration of A-585539, another α7 nAChR agonist with limited brain penetration, suggesting that these effects are mediated by peripheral α7 nAChRs. A-833834 was also efficacious in suppressing TNF-α release in mouse serum following oral administration in zymosan-induced peritonitis. These studies collectively demonstrate that selectively targeting α7 nAChRs could offer a novel therapeutic modality to treat acute and chronic inflammatory disease states.
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Affiliation(s)
- Jinhe Li
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, IL 60064, United States
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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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Gopalakrishnan SM, Philip BM, Gronlien JH, Malysz J, Anderson DJ, Gopalakrishnan M, Warrior U, Burns DJ. Functional characterization and high-throughput screening of positive allosteric modulators of α7 nicotinic acetylcholine receptors in IMR-32 neuroblastoma cells. Assay Drug Dev Technol 2011; 9:635-45. [PMID: 21309712 DOI: 10.1089/adt.2010.0319] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
α7 nicotinic acetylcholine receptors (nAChRs) are characterized by relatively low ACh sensitivity, rapid activation, and fast desensitization kinetics. ACh/agonist evoked currents at the α7 nAChR are transient, and, typically, calcium flux responses are difficult to detect using conventional fluorometric assay techniques. One approach to study interactions of agonists with the α7 nAChR is by utilizing positive allosteric modulators (PAMs). In this study, we demonstrate that inclusion of type II PAMs such as PNU-120596, but not type I, can enable detection of endogenous α7 nAChR-mediated calcium responses in human neuroblastoma (IMR-32) cells. Using this approach, we characterized the pharmacological profile of nicotine, epibatidine, choline, and other nAChR agonists such as PNU-282987, SSR-180711, GTS-21, OH-GTS21, tropisetron, NS6784, and A-582941. The rank order potency of agonists well correlated with α7 nAChR binding affinities measured in brain membranes. Inhibition of calcium response by methyllycaconitine in the presence of increasing concentrations of PNU-282987 or PNU-120596 revealed that the IC(50) value of methyllycaconitine was sensitive to varying concentrations of the agonist, but not that of the PAM. This format demonstrated the feasibility of this approach for high-throughput screening to identify small molecule, PAMs, which were further confirmed in electrophysiological assays of human α7 nAChR expressed in oocytes.
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Affiliation(s)
- Sujatha M Gopalakrishnan
- Advanced Technology, Global Pharmaceutical Research & Development, Abbott Laboratories, Abbott Park, Illinois 60064, USA.
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Dinklo T, Shaban H, Thuring JW, Lavreysen H, Stevens KE, Zheng L, Mackie C, Grantham C, Vandenberk I, Meulders G, Peeters L, Verachtert H, De Prins E, Lesage ASJ. Characterization of 2-[[4-fluoro-3-(trifluoromethyl)phenyl]amino]-4-(4-pyridinyl)-5-thiazolemethanol (JNJ-1930942), a novel positive allosteric modulator of the {alpha}7 nicotinic acetylcholine receptor. J Pharmacol Exp Ther 2010; 336:560-74. [PMID: 21084390 DOI: 10.1124/jpet.110.173245] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The α(7) nicotinic acetylcholine receptor (nAChR) is a potential therapeutic target for the treatment of cognitive deficits associated with schizophrenia, Alzheimer's disease, Parkinson's disease, and attention-deficit/hyperactivity disorder. Activation of α(7) nAChRs improved sensory gating and cognitive function in animal models and in early clinical trials. Here we describe the novel highly selective α(7) nAChR positive allosteric modulator, 2-[[4-fluoro-3-(trifluoromethyl)phenyl]amino]-4-(4-pyridinyl)-5-thiazolemethanol (JNJ-1930942). This compound enhances the choline-evoked rise in intracellular Ca(2+) levels in the GH4C1 cell line expressing the cloned human α(7) nAChR. JNJ-1930942 does not act on α4β2, α3β4 nAChRs or on the related 5-HT3A channel. Electrophysiological assessment in the GH4C1 cell line shows that JNJ-1930942 increases the peak and net charge response to choline, acetylcholine, and N-[(3R)-1-azabicyclo[2.2.2]oct-3-yl]-4-chlorobenzamide (PNU-282987). The potentiation is obtained mainly by affecting the receptor desensitization characteristics, leaving activation and deactivation kinetics as well as recovery from desensitization relatively unchanged. Choline efficacy is increased over its full concentration response range, and choline potency is increased more than 10-fold. The potentiating effect is α(7) channel-dependent, because it is blocked by the α(7) antagonist methyllycaconitine. Moreover, in hippocampal slices, JNJ-1930942 enhances neurotransmission at hippocampal dentate gyrus synapses and facilitates the induction of long-term potentiation of electrically evoked synaptic responses in the dentate gyrus. In vivo, JNJ-1930942 reverses a genetically based auditory gating deficit in DBA/2 mice. JNJ-1930942 will be a useful tool to study the therapeutic potential of α(7) nAChR potentiation in central nervous system disorders in which a deficit in α(7) nAChR neurotransmission is hypothesized to be involved.
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Affiliation(s)
- Theo Dinklo
- Johnson & Johnson Pharmaceutical Research and Development, Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
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Wu J, Toyohara J, Tanibuchi Y, Fujita Y, Zhang J, Chen H, Matsuo M, Wang RF, Hashimoto K. Pharmacological characterization of [125I]CHIBA-1006 binding, a new radioligand for α7 nicotinic acetylcholine receptors, to rat brain membranes. Brain Res 2010; 1360:130-7. [DOI: 10.1016/j.brainres.2010.08.095] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Revised: 08/27/2010] [Accepted: 08/27/2010] [Indexed: 11/26/2022]
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Importance of M2-M3 loop in governing properties of genistein at the α7 nicotinic acetylcholine receptor inferred from α7/5-HT3A chimera. Eur J Pharmacol 2010; 647:37-47. [PMID: 20816816 DOI: 10.1016/j.ejphar.2010.08.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 07/04/2010] [Accepted: 08/21/2010] [Indexed: 11/20/2022]
Abstract
Genistein and 5-hydroxyindole (5-HI) potentiate the α7 nicotinic acetylcholine receptor current by primarily increasing peak amplitude, a property of type I α7 positive allosteric modulation. In this study, the effects of these two compounds were investigated at two different α7/5-HT(3) chimeras (chimera 1, comprising of extracellular α7 N-terminus fused to the remainder of 5-HT(3A), and chimera 2 containing an additional α7 encoded M2-M3 loop), and wild-type α7 and 5-HT(3A) receptors. Agonist-evoked responses, examined by expression of the chimeras in Xenopus laevis oocytes or HEK-293 cells, revealed that currents decayed slower and compounds {rank order: N-[(3R)-1-azabicyclo[2.2.2]oct-3-yl]-4-chlorobenzamide hydrochloride (PNU-282987)~2-(1,4-diazabicyclo[3.2.2]nonan-4-yl)-5-phenyl-1,3,4-oxadiazole (NS6784)>acetylcholine>choline} were more potent in chimera 2 than chimera 1 or α7 receptors. In chimera 2, genistein and 5-HI potentiated agonist-evoked responses (EC(50): 4-5 μM for genistein and 300-500 μM for 5-HI) and at higher concentrations evoked current directly consistent with ago-allosteric modulation. At chimera 1 and 5-HT(3A) receptors, neither compound directly evoked any current and 5-HI, only at chimera 1, was able to potentiate agonist-evoked responses. Genistein and 5-HI did not inhibit the binding of the α7 agonist [(3)H](1S,4S)-2,2-dimethyl-5-(6-phenylpyridazin-3-yl)-5-aza-2-azoniabicyclo[2.2.1] heptane ([(3)H]A-585539) to rat brain or chimera 2. In summary, this study supports the role of the M2-M3 loop being critical for the positive allosteric effect of genistein, but not 5-HI, and in agonist-evoked response fine-tuning. The identification of distinct α7 receptor modulatory sites offers unique opportunities for developing CNS therapeutics and understanding its pharmacology.
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Tanibuchi Y, Wu J, Toyohara J, Fujita Y, Iyo M, Hashimoto K. Characterization of [3H]CHIBA-1001 binding to α7 nicotinic acetylcholine receptors in the brain from rat, monkey, and human. Brain Res 2010; 1348:200-8. [DOI: 10.1016/j.brainres.2010.06.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Revised: 05/31/2010] [Accepted: 06/01/2010] [Indexed: 11/29/2022]
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In vitro binding characteristics of [3H]AZ11637326, a novel alpha7-selective neuronal nicotinic receptor agonist radioligand. Eur J Pharmacol 2010; 645:63-9. [PMID: 20674564 DOI: 10.1016/j.ejphar.2010.07.035] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 06/09/2010] [Accepted: 07/15/2010] [Indexed: 11/23/2022]
Abstract
AZ11637326 (5'-(2-fluoro[3,4,5(-3)H3]phenyl)-spiro[1-azabicyclo [2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine) is a potent partial agonist at the human alpha7 neuronal nicotinic receptor with sub-nanomolar affinity for the human and rat alpha7 [(125)I]alpha-bungarotoxin binding sites. In a search for novel agonist radioligands and imaging ligands for the alpha7 nicotinic receptor, [(3)H]AZ11637326 was synthesized and its in vitro membrane binding properties were characterized. [(3)H]AZ11637326 bound to halpha7-HEK membranes with high specificity (>95%), high affinity (230 pM) and a B(max) of 460 fmol/mg. The rank order of affinity of nicotinic standards determined with [(3)H]AZ11637326 strongly correlated with those determined using the classical alpha7 antagonist [(125)I]alpha-bungarotoxin, indicating that [(3)H]AZ11637326 bound to halpha7-HEK membranes with an alpha7 nicotinic-like pharmacology. The K(i) values for the standards were on average 2.3-fold lower affinity than determined using the prototypical alpha7 nicotinic antagonist [(125)I]alpha-bungarotoxin. Because [(3)H]AZ11637326 specific binding is rapid and reversible, the K(i) values determined using this ligand are more accurate estimates of affinity than those determined using the kinetically sluggish [(125)I]alpha-bungarotoxin. [(3)H]AZ11637326 also bound to a high affinity (510 pM), nicotine-sensitive site on rat hippocampal membranes with an average B(max) of 55 fmol/mg. With rat hippocampal membranes, the nicotine-sensitive fraction of total binding was sub-optimal for a radioligand (~50%), yet the potencies and rank order of the K(i) values for standards were consistent with an alpha7 nicotinic pharmacology. Overall, these studies indicate that [(3)H]AZ11637326 is a useful new in vitro probe of the alpha7 nicotinic receptor agonist site and support its potential utility for in vivo receptor occupancy studies.
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Li T, Bunnelle WH, Ryther KB, Anderson DJ, Malysz J, Helfrich R, Grønlien JH, Håkerud M, Peters D, Schrimpf MR, Gopalakrishnan M, Ji J. Syntheses and structure–activity relationship (SAR) studies of 2,5-diazabicyclo[2.2.1]heptanes as novel α7 neuronal nicotinic receptor (NNR) ligands. Bioorg Med Chem Lett 2010; 20:3636-9. [DOI: 10.1016/j.bmcl.2010.04.105] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Revised: 04/22/2010] [Accepted: 04/23/2010] [Indexed: 10/19/2022]
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Toyohara J, Hashimoto K. α7 Nicotinic Receptor Agonists: Potential Therapeutic Drugs for Treatment of Cognitive Impairments in Schizophrenia and Alzheimer's Disease. THE OPEN MEDICINAL CHEMISTRY JOURNAL 2010; 4:37-56. [PMID: 21249164 PMCID: PMC3023065 DOI: 10.2174/1874104501004010037] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Revised: 10/23/2009] [Accepted: 10/30/2009] [Indexed: 01/19/2023]
Abstract
Accumulating evidence suggests that α7 nicotinic receptors (α7 nAChRs), a subtype of nAChRs, play a role in the pathophysiology of neuropsychiatric diseases, including schizophrenia and Alzheimer's disease (AD). A number of psychopharmacological and genetic studies shown that α7 nAChRs play an important role in the deficits of P50 auditory evoked potential in patients with schizophrenia, and that (α nAChR agonists would be potential therapeutic drugs for cognitive impairments associated with P50 deficits in schizophrenia. Furthermore, some studies have demonstrated that α7 nAChRs might play a key role in the amyloid-β (Aβ)-mediated pathology of AD, and that α7 nAChR agonists would be potential therapeutic drugs for Aβ deposition in the brains of patients with AD. Interestingly, the altered expression of α7 nAChRs in the postmortem brain tissues from patients with schizophrenia and AD has been reported. Based on all these findings, selective α7 nAChR agonists can be considered potential therapeutic drugs for cognitive impairments in both schizophrenia and AD. In this article, we review the recent research into the role of α7 nAChRs in the pathophysiology of these diseases and into the potential use of novel α7 nAChR agonists as therapeutic drugs.
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Affiliation(s)
- Jun Toyohara
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan
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Malysz J, Anderson DJ, Grønlien JH, Ji J, Bunnelle WH, Håkerud M, Thorin-Hagene K, Ween H, Helfrich R, Hu M, Gubbins E, Gopalakrishnan S, Puttfarcken PS, Briggs CA, Li J, Meyer MD, Dyhring T, Ahring PK, Nielsen EØ, Peters D, Timmermann DB, Gopalakrishnan M. In vitro pharmacological characterization of a novel selective alpha7 neuronal nicotinic acetylcholine receptor agonist ABT-107. J Pharmacol Exp Ther 2010; 334:863-74. [PMID: 20504915 DOI: 10.1124/jpet.110.167072] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Enhancement of alpha7 nicotinic acetylcholine receptor (nAChR) activity is considered a therapeutic approach for ameliorating cognitive deficits present in Alzheimer's disease and schizophrenia. In this study, we describe the in vitro profile of a novel selective alpha7 nAChR agonist, 5-(6-[(3R)-1-azabicyclo[2,2,2]oct-3-yloxy]pyridazin-3-yl)-1H-indole (ABT-107). ABT-107 displayed high affinity binding to alpha7 nAChRs [rat or human cortex, [(3)H](1S,4S)-2,2-dimethyl-5-(6-phenylpyridazin-3-yl)-5-aza-2-azoniabicyclo[2.2.1]heptane (A-585539), K(i) = 0.2-0.6 nM or [(3)H]methyllycaconitine (MLA), 7 nM] that was at least 100-fold selective versus non-alpha7 nAChRs and other receptors. Functionally, ABT-107 did not evoke detectible currents in Xenopus oocytes expressing human or nonhuman alpha3beta4, chimeric (alpha6/alpha3)beta4, or 5-HT(3A) receptors, and weak or negligible Ca(2+) responses in human neuroblastoma IMR-32 cells (alpha3* function) and human alpha4beta2 and alpha4beta4 nAChRs expressed in human embryonic kidney 293 cells. ABT-107 potently evoked human and rat alpha7 nAChR current responses in oocytes (EC(50), 50-90 nM total charge, approximately 80% normalized to acetylcholine) that were enhanced by the positive allosteric modulator (PAM) 4-[5-(4-chloro-phenyl)-2-methyl-3-propionyl-pyrrol-1-yl]-benzenesulfonamide (A-867744). In rat hippocampus, ABT-107 alone evoked alpha7-like currents, which were inhibited by the alpha7 antagonist MLA. In dentate gyrus granule cells, ABT-107 enhanced spontaneous inhibitory postsynaptic current activity when coapplied with A-867744. In the presence of an alpha7 PAM [A-867744 or N-[(3R)-1-azabicyclo[2.2.2]oct-3-yl]-4-chlorobenzamide hydrochloride (PNU-120596)], the addition of ABT-107 elicited MLA-sensitive alpha7 nAChR-mediated Ca(2+) signals in IMR-32 cells and rat cortical cultures and enhanced extracellular signal-regulated kinase phosphorylation in differentiated PC-12 cells. ABT-107 was also effective in protecting rat cortical cultures against glutamate-induced toxicity. In summary, ABT-107 is a selective high affinity alpha7 nAChR agonist suitable for characterizing the roles of this subtype in pharmacological studies.
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Affiliation(s)
- John Malysz
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott, Abbott Park, Illinois 60064-6125, USA.
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Bitner RS, Bunnelle WH, Decker MW, Drescher KU, Kohlhaas KL, Markosyan S, Marsh KC, Nikkel AL, Browman K, Radek R, Anderson DJ, Buccafusco J, Gopalakrishnan M. In Vivo Pharmacological Characterization of a Novel Selective α7 Neuronal Nicotinic Acetylcholine Receptor Agonist ABT-107: Preclinical Considerations in Alzheimer's Disease. J Pharmacol Exp Ther 2010; 334:875-86. [DOI: 10.1124/jpet.110.167213] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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Hu M, Gopalakrishnan M, Li J. Positive allosteric modulation of alpha7 neuronal nicotinic acetylcholine receptors: lack of cytotoxicity in PC12 cells and rat primary cortical neurons. Br J Pharmacol 2010; 158:1857-64. [PMID: 20050184 DOI: 10.1111/j.1476-5381.2009.00474.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND AND PURPOSE alpha7-Nicotinic acetylcholine receptors (alpha7 nAChRs) play an important role in cognitive function. Positive allosteric modulators (PAMs) amplify effects of alpha7 nAChR agonist and could provide an approach for treatment of cognitive deficits in neuropsychiatric diseases. PAMs can either predominantly affect the apparent peak current response (type I) or increase both the apparent peak current response and duration of channel opening, due to prolonged desensitization (type II). The delay of receptor desensitization by type II PAMs raises the possibility of Ca2+-induced toxicity through prolonged activation of alpha7 nAChRs. The present study addresses whether type I and II PAMs exhibit different cytotoxicity profiles. EXPERIMENTAL APPROACH The present studies evaluated cytotoxic effects of type I PAM [N-(4-chlorophenyl)]-alpha-[(4-chlorophenyl)-aminomethylene]-3-methyl-5-isoxazoleacet-amide (CCMI) and type II PAM 1-[5-chloro-2,4-dimethoxy-phenyl]-3-[5-methyl-isoxazol-3-yl]-urea (PNU-120596), or 4-[5-(4chloro-phenyl)-2-methyl-3-propionyl-pyrrol-1-yl]-benzenesulphonamide (A-867744). The studies used cultures of PC12 cells and primary cultures of rat cortical neuronal cells. KEY RESULTS Our results showed that neither type I nor type II PAMs had any detrimental effect on cell integrity or cell viability. In particular, type II PAMs did not affect neuron number and neurite outgrowth under conditions when alpha7 nAChR activity was measured by Ca2+ influx and extracellular signal-regulated kinases 1 and 2 phosphorylation, following exposure to alpha7 nAChR agonists. CONCLUSIONS AND IMPLICATIONS This study demonstrated that both type I and type II alpha7 nAChR selective PAMs, although exhibiting differential electrophysiological profiles, did not exert cytotoxic effects in cells endogenously expressing alpha7 nAChRs.
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Affiliation(s)
- Min Hu
- Neuroscience Research, Global Pharmaceutical Research & Development, Abbott Laboratories, Abbott Park, Illinois 60064-6125, USA
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In vivo evaluation of alpha7 nicotinic acetylcholine receptor agonists [11C]A-582941 and [11C]A-844606 in mice and conscious monkeys. PLoS One 2010; 5:e8961. [PMID: 20126539 PMCID: PMC2813863 DOI: 10.1371/journal.pone.0008961] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Accepted: 01/12/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The alpha7 nicotinic acetylcholine receptors (nAChRs) play an important role in the pathophysiology of neuropsychiatric diseases such as schizophrenia and Alzheimer's disease. The goal of this study was to evaluate the two carbon-11-labeled alpha7 nAChR agonists [(11)C]A-582941 and [(11)C]A-844606 for their potential as novel positron emission tomography (PET) tracers. METHODOLOGY/PRINCIPAL FINDINGS The two tracers were synthesized by methylation of the corresponding desmethyl precursors using [(11)C]methyl triflate. Effects of receptor blockade in mice were determined by coinjection of either tracer along with a carrier or an excess amount of a selective alpha7 nAChR agonist (SSR180711). Metabolic stability was investigated using radio-HPLC. Dynamic PET scans were performed in conscious monkeys with/without SSR180711-treatment. [(11)C]A-582941 and [(11)C]A-844606 showed high uptake in the mouse brain. Most radioactive compounds in the brain were detected as an unchanged form. However, regional selectivity and selective receptor blockade were not clearly observed for either compound in the mouse brain. On the other hand, the total distribution volume of [(11)C]A-582941 and [(11)C]A-844606 was high in the hippocampus and thalamus but low in the cerebellum in the conscious monkey brain, and reduced by pretreatment with SSR180711. CONCLUSIONS/SIGNIFICANCE A nonhuman primate study suggests that [(11)C]A-582941 and [(11)C]A-844606 would be potential PET ligands for imaging alpha7 nAChRs in the human brain.
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Structure–activity relationships of N-substituted ligands for the α7 nicotinic acetylcholine receptor. Bioorg Med Chem Lett 2010; 20:104-7. [DOI: 10.1016/j.bmcl.2009.11.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Accepted: 11/09/2009] [Indexed: 11/18/2022]
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40
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LGIC. Br J Pharmacol 2009. [DOI: 10.1111/j.1476-5381.2009.00502.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Acetylcholine (nicotinic). Br J Pharmacol 2009. [DOI: 10.1111/j.1476-5381.2009.00502_3.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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Briggs CA, Grønlien JH, Curzon P, Timmermann DB, Ween H, Thorin-Hagene K, Kerr P, Anderson DJ, Malysz J, Dyhring T, Olsen GM, Peters D, Bunnelle WH, Gopalakrishnan M. Role of channel activation in cognitive enhancement mediated by alpha7 nicotinic acetylcholine receptors. Br J Pharmacol 2009; 158:1486-94. [PMID: 19845675 DOI: 10.1111/j.1476-5381.2009.00426.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND AND PURPOSE Several agonists of the alpha7 nicotinic acetylcholine receptor (nAChR) have been developed for treatment of cognitive deficits. However, agonist efficacy in vivo is difficult to reconcile with rapid alpha7 nAChR desensitization in vitro; and furthermore, the correlation between in vitro receptor efficacy and in vivo behavioural efficacy is not well delineated. The possibility that agonists of this receptor actually function in vivo as inhibitors via desensitization has not been finally resolved. EXPERIMENTAL APPROACH Two structurally related alpha7 nAChR agonists were characterized and used to assess the degree of efficacy required in a behavioural paradigm. KEY RESULTS NS6784 activated human and rat alpha7 nAChR with EC(50)s of 0.72 and 0.88 microM, and apparent efficacies of 77 and 97% respectively. NS6740, in contrast, displayed little efficacy at alpha7 nAChR (<2% in oocytes, < or =8% in GH4C1 cells), although its agonist-like properties were revealed by adding a positive allosteric modulator of alpha7 nAChRs or using the slowly desensitizing alpha7V274T receptor. In mouse inhibitory avoidance (IA) memory retention, NS6784 enhanced performance as did the 60% partial agonist A-582941. In contrast, NS6740 did not enhance performance, but blocked effects of A-582941. CONCLUSIONS AND IMPLICATIONS Collectively, these findings suggest that a degree of alpha7 nAChR agonist efficacy is required for behavioural effects in the IA paradigm, and that such behavioural efficacy is not due to alpha7 nAChR desensitization. Also, a partial agonist of very low efficacy for this receptor could be used as an inhibitor, in the absence of alpha7 nAChR antagonists with favourable CNS penetration.
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Affiliation(s)
- Clark A Briggs
- Neuroscience Research, Abbott Laboratories, Abbott Park, IL, USA.
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Malysz J, Grønlien JH, Timmermann DB, Håkerud M, Thorin-Hagene K, Ween H, Trumbull JD, Xiong Y, Briggs CA, Ahring PK, Dyhring T, Gopalakrishnan M. Evaluation of α7 Nicotinic Acetylcholine Receptor Agonists and Positive Allosteric Modulators Using the Parallel Oocyte Electrophysiology Test Station. Assay Drug Dev Technol 2009; 7:374-90. [DOI: 10.1089/adt.2009.0194] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- John Malysz
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott, Abbott Park, Illinois
| | - Jens H. Grønlien
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott, Oslo, Norway
| | | | - Monika Håkerud
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott, Oslo, Norway
| | - Kirsten Thorin-Hagene
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott, Oslo, Norway
| | - Hilde Ween
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott, Oslo, Norway
| | - Jonathan D. Trumbull
- Advanced Technology, Global Pharmaceutical Research and Development, Abbott, Abbott Park, Illinois
| | | | - Clark A. Briggs
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott, Abbott Park, Illinois
| | | | - Tino Dyhring
- Drug Discovery, NeuroSearch A/S, Ballerup, Denmark
| | - Murali Gopalakrishnan
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott, Abbott Park, Illinois
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Malysz J, Grønlien JH, Anderson DJ, Håkerud M, Thorin-Hagene K, Ween H, Wetterstrand C, Briggs CA, Faghih R, Bunnelle WH, Gopalakrishnan M. In vitro pharmacological characterization of a novel allosteric modulator of alpha 7 neuronal acetylcholine receptor, 4-(5-(4-chlorophenyl)-2-methyl-3-propionyl-1H-pyrrol-1-yl)benzenesulfonamide (A-867744), exhibiting unique pharmacological profile. J Pharmacol Exp Ther 2009; 330:257-67. [PMID: 19389923 DOI: 10.1124/jpet.109.151886] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Targeting alpha7 neuronal acetylcholine receptors (nAChRs) with selective agonists and positive allosteric modulators (PAMs) is considered a therapeutic approach for managing cognitive deficits in schizophrenia and Alzheimer's disease. In this study, we describe a novel type II alpha7 PAM, 4-(5-(4-chlorophenyl)-2-methyl-3-propionyl-1H-pyrrol-1-yl)benzenesulfonamide (A-867744), that exhibits a unique pharmacological profile. In oocytes expressing alpha7 nAChRs, A-867744 potentiated acetylcholine (ACh)-evoked currents, with an EC(50) value of approximately 1 microM. At highest concentrations of A-867744 tested, ACh-evoked currents were essentially nondecaying. At lower concentrations, no evidence of a distinct secondary component was evident in contrast to 4-naphthalen-1-yl-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-sulfonic acid amide (TQS), another type II alpha7 PAM. In the presence of A-867744, ACh concentration responses were potentiated by increases in potency, Hill slope, and maximal efficacy. When examined in rat hippocampus CA1 stratum radiatum interneurons or dentate gyrus granule cells, A-867744 (10 microM) increased choline-evoked alpha7 currents and recovery from inhibition/desensitization, and enhanced spontaneous inhibitory postsynaptic current activity. A-867744, like other alpha7 PAMs tested [1-(5-chloro-2-hydroxyphenyl)-3-(2-chloro-5-trifluoromethyl-phenyl)urea (NS1738), TQS, and 1-(5-chloro-2,4-dimethoxy-phenyl)-3-(5-methyl-isoxazol-3-yl)-urea (PNU-120596)], did not displace the binding of [(3)H]methyllycaconitine to rat cortex alpha7(*) nAChRs. However, unlike these PAMs, A-867744 displaced the binding of the agonist [(3)H](1S,4S)-2,2-dimethyl-5-(6-phenylpyridazin-3-yl)-5-aza-2-azoniabicyclo[2.2.1]heptane (A-585539) in rat cortex, with a K(i) value of 23 nM. A-867744 neither increased agonist-evoked responses nor displaced the binding of [(3)H]A-585539 in an alpha7/5-hydroxytryptamine(3) (alpha7/5-HT(3)) chimera, suggesting an interaction distinct from the alpha7 N terminus or M2-3 loop. In addition, A-867744 failed to potentiate responses mediated by 5-HT(3A) or alpha3beta4 and alpha4beta2 nAChRs. In summary, this study identifies a novel and selective alpha7 PAM showing activity at recombinant and native alpha7 nAChRs exhibiting a unique pharmacological interaction with the receptor.
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Affiliation(s)
- John Malysz
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Rd., Abbott Park, IL 60064-6125, USA.
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Bunnelle WH, Tietje KR, Frost JM, Peters D, Ji J, Li T, Scanio MJC, Shi L, Anderson DJ, Dyhring T, Grønlien JH, Ween H, Thorin-Hagene K, Meyer MD. Octahydropyrrolo[3,4-c]pyrrole: A Diamine Scaffold for Construction of Either α4β2 or α7-Selective Nicotinic Acetylcholine Receptor (nAChR) Ligands. Substitutions that Switch Subtype Selectivity. J Med Chem 2009; 52:4126-41. [DOI: 10.1021/jm900249k] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- William H. Bunnelle
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Karin R. Tietje
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Jennifer M. Frost
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Dan Peters
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Jianguo Ji
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Tao Li
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Marc J. C. Scanio
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Lei Shi
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - David J. Anderson
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Tino Dyhring
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Jens H. Grønlien
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Hilde Ween
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Kirsten Thorin-Hagene
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
| | - Michael D. Meyer
- Neuroscience Research, Abbott Laboratories, Department R47W, Building AP9A, Abbott Park, Illinois 60064-6117
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
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El Kouhen R, Hu M, Anderson DJ, Li J, Gopalakrishnan M. Pharmacology of alpha7 nicotinic acetylcholine receptor mediated extracellular signal-regulated kinase signalling in PC12 cells. Br J Pharmacol 2009; 156:638-48. [PMID: 19226255 DOI: 10.1111/j.1476-5381.2008.00069.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND AND PURPOSE Neuronal nicotinic acetylcholine receptors (nAChR) can modulate cell survival and memory processing. The involvement of specific nAChR subtypes in downstream signalling events has been ill defined thus far, because of a lack of subtype-selective ligands. In this study, we investigated activation and modulation of alpha7 nAChR-mediated phosphorylation of extracellular signal-regulated kinases (ERK1/2) in PC12 cells, using selective agonists and positive allosteric modulators. EXPERIMENTAL APPROACH We used undifferentiated PC12 cells endogenously expressing alpha7 nAChR for both biochemical and functional studies. ERK phosphorylation changes were measured by using a novel In-Cell Western procedure. alpha7 nAChR-mediated Ca(2+) signalling was determined by using the fluorometric imaging plate reader assay. KEY RESULTS Robust induction of ERK phosphorylation followed exposure of PC12 cells to the selective agonist PNU-282987 in the presence of the alpha7 nAChR modulator PNU-120596. ERK phosphorylation was transient and was attenuated by the selective antagonist methyllycaconitine. Consistent with allosteric modulation of alpha7 nAChRs, PNU-120596 enhanced both the agonist potency and efficacy in activating ERK. Moreover, alpha7 nAChR agonists could be quantitatively differentiated based on their potency in activating ERK signalling. The rank order of potencies correlated fairly well with the corresponding binding K(i) values of these alpha7 nAChR agonists. CONCLUSIONS AND IMPLICATIONS The present work extends previous observations demonstrating the involvement of alpha7 nAChRs in ERK1/2 phosphorylation in PC12 cells. The In-Cell Western procedure allowed a detailed investigation of alpha7 nAChR function and downstream ERK signalling in response to agonist and allosteric modulators.
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Affiliation(s)
- R El Kouhen
- Neuroscience Research, Abbott Laboratories, Department R47W, Abbott Park, IL 60064-6125, USA. E-mail:
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Anderson DJ. Radioligand binding characterization of neuronal nicotinic acetylcholine receptors. CURRENT PROTOCOLS IN PHARMACOLOGY 2008; Chapter 1:Unit1.8. [PMID: 22294217 DOI: 10.1002/0471141755.ph0108s43] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Described in this unit are radioligand binding protocols for three neuronal nicotinic acetylcholine receptor (nAChR) subtypes. Detailed descriptions of binding protocols are presented for the two predominant CNS subtypes of nAChRs, α4β2 and α7, as well as the ganglionic α3β4 nAChR. [(3)H]Cytisine is utilized for α4β2 nAChRs, while [(3)H]methyllycaconitine is utilized for α7 nAChRs, both in rat brain. α3β4 nAChRs in IMR-32 cells are labeled with [(3)H]epibatidine. Reference data are presented, as well as commentary on the current state of neuronal nicotinic receptor research.
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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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Tietje KR, Anderson DJ, Bitner RS, Blomme EA, Brackemeyer PJ, Briggs CA, Browman KE, Bury D, Curzon P, Drescher KU, Frost JM, Fryer RM, Fox GB, Gronlien JH, Håkerud M, Gubbins EJ, Halm S, Harris R, Helfrich RJ, Kohlhaas KL, Law D, Malysz J, Marsh KC, Martin RL, Meyer MD, Molesky AL, Nikkel AL, Otte S, Pan L, Puttfarcken PS, Radek RJ, Robb HM, Spies E, Thorin-Hagene K, Waring JF, Ween H, Xu H, Gopalakrishnan M, Bunnelle WH. Preclinical Characterization of A-582941: A Novel α7 Neuronal Nicotinic Receptor Agonist with Broad Spectrum Cognition-Enhancing Properties. CNS Neurosci Ther 2008. [DOI: 10.1111/j.1755-5949.2008.00037.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Tietje KR, Anderson DJ, Bitner RS, Blomme EA, Brackemeyer PJ, Briggs CA, Browman KE, Bury D, Curzon P, Drescher KU, Frost JM, Fryer RM, Fox GB, Gronlien JH, Håkerud M, Gubbins EJ, Halm S, Harris R, Helfrich RJ, Kohlhaas KL, Law D, Malysz J, Marsh KC, Martin RL, Meyer MD, Molesky AL, Nikkel AL, Otte S, Pan L, Puttfarcken PS, Radek RJ, Robb HM, Spies E, Thorin‐Hagene K, Waring JF, Ween H, Xu H, Gopalakrishnan M, Bunnelle WH. Preclinical characterization of A-582941: a novel alpha7 neuronal nicotinic receptor agonist with broad spectrum cognition-enhancing properties. CNS Neurosci Ther 2008; 14:65-82. [PMID: 18482100 PMCID: PMC6494002 DOI: 10.1111/j.1527-3458.2008.00037.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Among the diverse sets of nicotinic acetylcholine receptors (nAChRs), the alpha7 subtype is highly expressed in the hippocampus and cortex and is thought to play important roles in a variety of cognitive processes. In this review, we describe the properties of a novel biaryl diamine alpha7 nAChR agonist, A-582941. A-582941 was found to exhibit high-affinity binding and partial agonism at alpha7 nAChRs, with acceptable pharmacokinetic properties and excellent distribution to the central nervous system (CNS). In vitro and in vivo studies indicated that A-582941 activates signaling pathways known to be involved in cognitive function such as ERK1/2 and CREB phosphorylation. A-582941 enhanced cognitive performance in behavioral models that capture domains of working memory, short-term recognition memory, memory consolidation, and sensory gating deficit. A-582941 exhibited a benign secondary pharmacodynamic and tolerability profile as assessed in a battery of assays of cardiovascular, gastrointestinal, and CNS function. The studies summarized in this review collectively provide preclinical validation that alpha7 nAChR agonism offers a mechanism with potential to improve cognitive deficits associated with various neurodegenerative and psychiatric disorders.
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Affiliation(s)
- Karin R. Tietje
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - David J. Anderson
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - R. Scott Bitner
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Eric A. Blomme
- Department of Cellular and Molecular Toxicology, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Paul J. Brackemeyer
- Manufacturing Science and Technology, Global Pharmaceutical Operations, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Clark A. Briggs
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Kaitlin E. Browman
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Dagmar Bury
- Toxicology & Pathology, Global Pharmaceutical Research and Development, Abbott Laboratories, Ludwigshafen, Germany
| | - Peter Curzon
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Karla U. Drescher
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Ludwigshafen, Germany
| | - Jennifer M. Frost
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Ryan M. Fryer
- Department of Integrative Pharmacology, Global Pharmaceutical Research & Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Gerard B. Fox
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Jens Halvard Gronlien
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Monika Håkerud
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Earl J. Gubbins
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Sabine Halm
- Toxicology & Pathology, Global Pharmaceutical Research and Development, Abbott Laboratories, Ludwigshafen, Germany
| | - Richard Harris
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Rosalind J. Helfrich
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Kathy L. Kohlhaas
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Devalina Law
- Manufacturing Science and Technology, Global Pharmaceutical Operations, Abbott Laboratories, Abbott Park, Illinois, USA
| | - John Malysz
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Kennan C. Marsh
- Pharmacokinetics and Metabolism, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Ilinois, USA
| | - Ruth L. Martin
- Department of Integrative Pharmacology, Global Pharmaceutical Research & Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Michael D. Meyer
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Angela L. Molesky
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Arthur L. Nikkel
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Stephani Otte
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Liping Pan
- Pharmacokinetics and Metabolism, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Ilinois, USA
| | - Pamela S. Puttfarcken
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Richard J. Radek
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Holly M. Robb
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Eva Spies
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Ludwigshafen, Germany
| | - Kirsten Thorin‐Hagene
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Jeffrey F. Waring
- Department of Cellular and Molecular Toxicology, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Hilde Ween
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - Hongyu Xu
- Pharmacokinetics and Metabolism, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Ilinois, USA
| | - Murali Gopalakrishnan
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
| | - William H. Bunnelle
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois, USA
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