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Acker BA, Badescu VO, Berkenpas MB, Groppi VE, Hajós M, Higdon NR, Hurst RS, Jon Jacobsen E, Margolis BJ, McWhorter WW, Myers JK, Piotrowski DW, Rogers BN, Sarapa D, Vetman TN, Walker DP, Wall TM, Wilhite DM, Wishka DG, Xu W, Yates KM. Positive allosteric modulators of the α7 nicotinic acetylcholine receptor: SAR investigation around PNU-120596. Bioorg Med Chem Lett 2023; 93:129433. [PMID: 37557923 DOI: 10.1016/j.bmcl.2023.129433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 06/17/2023] [Accepted: 08/03/2023] [Indexed: 08/11/2023]
Abstract
The α7 nicotinic acetylcholine receptor is a calcium permeable, ligand-gated ion channel that modulates synaptic transmission in the hippocampus, thalamus, and cerebral cortex. Previously disclosed work described PNU-120596 that acts as a powerful positive allosteric modulator of the α7 nicotinic acetylcholine receptor. The initial structure-activity relationships around PNU-120596 were gleaned from screening a large thiazole library. Independent systematic examination of the aryl and heteroaryl groups resulted in compounds with enhanced potency and improved physico-chemical properties culminating in the identification of 16 (PHA-758454). In the presence of acetylcholine, 16 enhanced evoked currents in rat hippocampal neurons. In a rat model of impaired sensory gating, treatment with 16 led to a reversal of the gating deficit in a dose-dependent manner. These results demonstrate that aryl heteroaryl ureas, like compound 16, may be useful tools for continued exploration of the unique biology of the α7 nicotinic acetylcholine receptor.
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Affiliation(s)
- Brad A Acker
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | | | | | | | - Mihaly Hajós
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | - Nicole R Higdon
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | - Raymond S Hurst
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | - E Jon Jacobsen
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | | | | | - Jason K Myers
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | | | - Bruce N Rogers
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | - Dusan Sarapa
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | | | - Daniel P Walker
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | - Theron M Wall
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | - David M Wilhite
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | - Donn G Wishka
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | - Wenjian Xu
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
| | - Karen M Yates
- Pfizer Worldwide Research & Development, Groton, CT 06340, USA
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2
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Sanders VR, Millar NS. Potentiation and allosteric agonist activation of α7 nicotinic acetylcholine receptors: binding sites and hypotheses. Pharmacol Res 2023; 191:106759. [PMID: 37023990 DOI: 10.1016/j.phrs.2023.106759] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/27/2023] [Accepted: 03/30/2023] [Indexed: 04/07/2023]
Abstract
Considerable progress has been made in recent years towards the identification and characterisation of novel subtype-selective modulators of nicotinic acetylcholine receptors (nAChRs). In particular, this has focussed on modulators of α7 nAChRs, a nAChR subtype that has been identified as a target for drug discovery in connection with a range of potential therapeutic applications. This review focusses upon α7-selective modulators that bind to receptor sites other than the extracellular 'orthosteric' agonist binding site for the endogenous agonist acetylcholine (ACh). Such compounds include those that are able to potentiate responses evoked by orthosteric agonists such as ACh (positive allosteric modulators; PAMs) and those that are able to activate α7 nAChRs by direct allosteric activation in the absence of an orthosteric agonist (allosteric agonists or 'ago-PAMs'). There has been considerable debate about the mechanism of action of α7-selective PAMs and allosteric agonists, much of which has centred around identifying the location of their binding sites on α7 nAChRs. Based on a variety of experimental evidence, including recent structural data, there is now clear evidence indicating that at least some α7-selective PAMs bind to an inter-subunit site located in the transmembrane domain. In contrast, there are differing hypotheses about the site or sites at which allosteric agonists bind to α7 nAChRs. It will be argued that the available evidence supports the conclusion that direct allosteric activation by allosteric agonists/ago-PAMs occurs via the same inter-subunit transmembrane site that has been identified for several α7-selective PAMs.
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Affiliation(s)
- Victoria R Sanders
- Division of Biosciences, University College London, London WC1E 6BT, United Kingdom
| | - Neil S Millar
- Division of Biosciences, University College London, London WC1E 6BT, United Kingdom.
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3
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Alpha7 nicotinic acetylcholine receptor agonist PHA-543613 improves memory deficits in presenilin 1 and presenilin 2 conditional double knockout mice. Exp Neurol 2023; 359:114271. [PMID: 36370840 DOI: 10.1016/j.expneurol.2022.114271] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 10/18/2022] [Accepted: 11/06/2022] [Indexed: 11/11/2022]
Abstract
Cholinergic system dysfunction has been considered as a critical feature of neurodegenerative progression in Alzheimer's disease (AD). The α7 nicotinic acetylcholine receptors (α7-nAChRs) are widely expressed in the hippocampus cortex and play an important role in memory formation, considered as potential therapeutic agents targets. However, underlying mechanisms have not been fully elucidated. Here, we combine behavioral, molecular biological methods with in vitro slice and in vivo multichannel electrophysiological recording techniques to investigate the molecular, cellular synaptic and neuronal mechanisms of activating α7-nAChR by PHA-543613 (a selective α7-nAChR agonist), which influences the impaired cognitive function using presenilin 1 (PS1) and presenilin 2 (PS2) conditional double knockout (cDKO) mice. Our results demonstrated that PHA-543613 treatment significantly improved the impaired hippocampus-related memory via recovering the reduced the hippocampal synaptic protein levels of α7-nAChR, NMADAR and AMPAR, thereby restoring the impaired post-tetanic potentiation (PTP), long-term potentiation (LTP), activation of molecular signaling pathway for neuronal protection, theta power and strength of theta-gamma phase-amplitude coupling (PAC) at hippocampus in 6-month-old cDKO mice. For the first time, we systematically reveal the mechanisms by which PHA-543613 improves memory deficits at different levels. Therefore, our findings may be significant for the development of therapeutic strategies for AD.
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Choudhary S, Abongwa M, Kashyap SS, Verma S, Mair GR, Kulke D, Martin RJ, Robertson AP. Nodulisporic acid produces direct activation and positive allosteric modulation of AVR-14B, a glutamate-gated chloride channel from adult Brugia malayi. Proc Natl Acad Sci U S A 2022; 119:e2111932119. [PMID: 35969762 PMCID: PMC9407656 DOI: 10.1073/pnas.2111932119] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 06/13/2022] [Indexed: 11/18/2022] Open
Abstract
Glutamate-gated chloride channels (GluCls) are unique to invertebrates and are targeted by macrocyclic lactones. In this study, we cloned an AVR-14B GluCl subunit from adult Brugia malayi, a causative agent of lymphatic filariasis in humans. To elucidate this channel's pharmacological properties, we used Xenopus laevis oocytes for expression and performed two-electrode voltage-clamp electrophysiology. The receptor was gated by the natural ligand L-glutamate (effective concentration, 50% [EC50] = 0.4 mM) and ivermectin (IVM; EC50 = 1.8 nM). We also characterized the effects of nodulisporic acid (NA) on Bma-AVR-14B and NA-produced dual effects on the receptor as an agonist and a type II positive allosteric modulator. Here we report characterization of the complex activity of NA on a nematode GluCl. Bma-AVR-14B demonstrated some unique pharmacological characteristics. IVM did not produce potentiation of L-glutamate-mediated responses but instead, reduced the channel's sensitivity for the ligand. Further electrophysiological exploration showed that IVM (at a moderate concentration of 0.1 nM) functioned as an inhibitor of both agonist and positive allosteric modulatory effects of NA. This suggests that IVM and NA share a complex interaction. The pharmacological properties of Bma-AVR-14B indicate that the channel is an important target of IVM and NA. In addition, the unique electrophysiological characteristics of Bma-AVR-14B could explain the observed variation in drug sensitivities of various nematode parasites. We have also shown the inhibitory effects of IVM and NA on adult worm motility using Worminator. RNA interference (RNAi) knockdown suggests that AVR-14 plays a role in influencing locomotion in B. malayi.
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Affiliation(s)
- Shivani Choudhary
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011
| | - Melanie Abongwa
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011
| | - Sudhanva S. Kashyap
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011
| | - Saurabh Verma
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011
| | - Gunnar R. Mair
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011
| | - Daniel Kulke
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011
| | - Richard J. Martin
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011
| | - Alan P. Robertson
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011
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Abstract
The α7-type nicotinic acetylcholine receptor is one of the most unique and interesting of all the members of the cys-loop superfamily of ligand-gated ion channels. Since it was first identified initially as a binding site for α-bungarotoxin in mammalian brain and later as a functional homomeric receptor with relatively high calcium permeability, it has been pursued as a potential therapeutic target for numerous indications, from Alzheimer disease to asthma. In this review, we discuss the history and state of the art for targeting α7 receptors, beginning with subtype-selective agonists and the basic pharmacophore for the selective activation of α7 receptors. A key feature of α7 receptors is their rapid desensitization by standard "orthosteric" agonist, and we discuss insights into the conformational landscape of α7 receptors that has been gained by the development of ligands binding to allosteric sites. Some of these sites are targeted by positive allosteric modulators that have a wide range of effects on the activation profile of the receptors. Other sites are targeted by direct allosteric agonist or antagonists. We include a perspective on the potential importance of α7 receptors for metabotropic as well as ionotropic signaling. We outline the challenges that exist for future development of drugs to target this important receptor and approaches that may be considered to address those challenges. SIGNIFICANCE STATEMENT: The α7-type nicotinic acetylcholine receptor (nAChR) is acknowledged as a potentially important therapeutic target with functional properties associated with both ionotropic and metabotropic signaling. The functional properties of α7 nAChR can be regulated in diverse ways with the variety of orthosteric and allosteric ligands described in this review.
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Affiliation(s)
- Roger L Papke
- Departments of Pharmacology and Therapeutics (R.L.P) and Chemistry (N.A.H.), University of Florida, Gainesville, FL
| | - Nicole A Horenstein
- Departments of Pharmacology and Therapeutics (R.L.P) and Chemistry (N.A.H.), University of Florida, Gainesville, FL
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Potasiewicz A, Faron-Gorecka A, Popik P, Nikiforuk A. Repeated treatment with alpha 7 nicotinic acetylcholine receptor ligands enhances cognitive processes and stimulates Erk1/2 and Arc genes in rats. Behav Brain Res 2021; 409:113338. [PMID: 33940049 DOI: 10.1016/j.bbr.2021.113338] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/02/2021] [Accepted: 04/28/2021] [Indexed: 10/21/2022]
Abstract
The α7 nicotinic acetylcholine receptor (α7 nAChR) is a potential target for the treatment of cognitive decline in patients with schizophrenia, Alzheimer's disease, and attention-deficit/hyperactivity disorder. Here we examined the promnesic activity of the α7 nAChR agonist (A582941), the type I (CCMI), and the type II (PNU120596) positive allosteric modulators (PAMs) in rats following single and repeated (once daily for seven days) treatment. To determine the neuronal mechanisms underlying the procognitive activity of the tested compounds, levels of the extracellular signal-regulated kinases (Erk1/2) and the activity-regulated cytoskeleton-associated protein (Arc) mRNAs were assessed in the frontal cortical and hippocampal brain regions. Using the novel object recognition test, we demonstrate that the lower doses of A582941 (0.1 mg/kg), CCMI (1 mg/kg), and PNU120596 (0.3 mg/kg) improved recognition memory after repeated but not single administration, suggesting a cumulative effect of repeated dosing. In contrast, the higher doses of A582941 (0.3 mg/kg), CCMI (3 mg/kg) and PNU120596 (1 mg/kg) demonstrated promnesic efficacy following both single and repeated administration. Subsequent in situ hybridization revealed that repeated treatment with A582941 and CCMI, but not PNU120596 enhanced mRNA expression of the Erk1/2 and Arc in the frontal cortex and hippocampus. Present data suggest that both the α7 nAChR agonist and PAMs exhibit procognitive effects after single and repeated administration. The increased level of the Erk1/2 and Arc genes is likely to be at least partially involved in this effect.
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Affiliation(s)
- Agnieszka Potasiewicz
- Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Behavioral Neuroscience and Drug Development, Krakow, Poland.
| | - Agata Faron-Gorecka
- Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Pharmacology, Krakow, Poland
| | - Piotr Popik
- Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Behavioral Neuroscience and Drug Development, Krakow, Poland
| | - Agnieszka Nikiforuk
- Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Behavioral Neuroscience and Drug Development, Krakow, Poland
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7
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Field M, Dorovykh V, Thomas P, Smart TG. Physiological role for GABA A receptor desensitization in the induction of long-term potentiation at inhibitory synapses. Nat Commun 2021; 12:2112. [PMID: 33837214 PMCID: PMC8035410 DOI: 10.1038/s41467-021-22420-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 03/03/2021] [Indexed: 01/03/2023] Open
Abstract
GABAA receptors (GABAARs) are pentameric ligand-gated ion channels distributed throughout the brain where they mediate synaptic and tonic inhibition. Following activation, these receptors undergo desensitization which involves entry into long-lived agonist-bound closed states. Although the kinetic effects of this state are recognised and its structural basis has been uncovered, the physiological impact of desensitization on inhibitory neurotransmission remains unknown. Here we describe an enduring form of long-term potentiation at inhibitory synapses that elevates synaptic current amplitude for 24 h following desensitization of GABAARs in response to agonist exposure or allosteric modulation. Using receptor mutants and allosteric modulators we demonstrate that desensitization of GABAARs facilitates their phosphorylation by PKC, which increases the number of receptors at inhibitory synapses. These observations provide a physiological relevance to the desensitized state of GABAARs, acting as a signal to regulate the efficacy of inhibitory synapses during prolonged periods of inhibitory neurotransmission.
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Affiliation(s)
- Martin Field
- Department of Neuroscience, Physiology and Pharmacology, UCL, London, UK
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Valentina Dorovykh
- Department of Neuroscience, Physiology and Pharmacology, UCL, London, UK
| | - Philip Thomas
- Department of Neuroscience, Physiology and Pharmacology, UCL, London, UK
| | - Trevor G Smart
- Department of Neuroscience, Physiology and Pharmacology, UCL, London, UK.
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8
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Verma MK, Goel RN, Bokare AM, Dandekar MP, Koul S, Desai S, Tota S, Singh N, Nigade PB, Patil VB, Modi D, Mehta M, Gundu J, Walunj SS, Karche NP, Sinha N, Kamboj RK, Palle VP. LL-00066471, a novel positive allosteric modulator of α7 nicotinic acetylcholine receptor ameliorates cognitive and sensorimotor gating deficits in animal models: Discovery and preclinical characterization. Eur J Pharmacol 2021; 891:173685. [PMID: 33127363 DOI: 10.1016/j.ejphar.2020.173685] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 10/21/2020] [Accepted: 10/26/2020] [Indexed: 01/20/2023]
Abstract
α7 nicotinic acetylcholine receptor (α7 nAChR) is an extensively validated target for several neurological and psychiatric conditions namely, dementia and schizophrenia, owing to its vital roles in cognition and sensorimotor gating. Positive allosteric modulation (PAM) of α7 nAChR represents an innovative approach to amplify endogenous cholinergic signaling in a temporally restricted manner in learning and memory centers of brain. α7 nAChR PAMs are anticipated to side-step burgeoning issues observed with several clinical-stage orthosteric α7 nAChR agonists, related to selectivity, tolerance/tachyphylaxis, thus providing a novel dimension in therapeutic strategy and pharmacology of α7 nAChR ion-channel. Here we describe a novel α7 nAChR PAM, LL-00066471, which potently amplified agonist-induced Ca2+ fluxes in neuronal IMR-32 neuroblastoma cells in a α-bungarotoxin (α-BTX) sensitive manner. LL-00066471 showed excellent oral bioavailability across species (mouse, rat and dog), low clearance and good brain penetration (B/P ratio > 1). In vivo, LL-00066471 robustly attenuated cognitive deficits in both procognitive and antiamnesic paradigms of short-term episodic and recognition memory in novel object recognition task (NORT) and social recognition task (SRT), respectively. Additionally, LL-00066471 mitigated apomorphine-induced sensorimotor gating deficits in acoustic startle reflex (ASR) and enhanced antipsychotic efficacy of olanzapine in conditioned avoidance response (CAR) task. Further, LL-00066471 corrected redox-imbalances and reduced cortico-striatal infarcts in stroke model. These finding together suggest that LL-00066471 has potential to symptomatically alleviate cognitive deficits associated with dementias, attenuate sensorimotor gating deficits in schizophrenia and correct redox-imbalances in cerebrovascular disorders. Therefore, LL-00066471 presents potential for management of cognitive impairments associated with neurological and psychiatric conditions.
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MESH Headings
- Animals
- Behavior, Animal/drug effects
- Brain/drug effects
- Brain/metabolism
- Brain/physiopathology
- Cell Line, Tumor
- Cholinergic Agents/pharmacokinetics
- Cholinergic Agents/pharmacology
- Cognition/drug effects
- Cognitive Dysfunction/metabolism
- Cognitive Dysfunction/physiopathology
- Cognitive Dysfunction/prevention & control
- Cognitive Dysfunction/psychology
- Disease Models, Animal
- Dogs
- Exploratory Behavior/drug effects
- Gait Disorders, Neurologic/metabolism
- Gait Disorders, Neurologic/physiopathology
- Gait Disorders, Neurologic/prevention & control
- Gait Disorders, Neurologic/psychology
- Ischemic Stroke/drug therapy
- Ischemic Stroke/metabolism
- Ischemic Stroke/physiopathology
- Male
- Mice, Inbred BALB C
- Open Field Test/drug effects
- Oxidative Stress/drug effects
- Rats, Sprague-Dawley
- Rats, Wistar
- Reflex, Startle/drug effects
- Sensory Gating/drug effects
- Signal Transduction
- Social Behavior
- alpha7 Nicotinic Acetylcholine Receptor/drug effects
- alpha7 Nicotinic Acetylcholine Receptor/metabolism
- Mice
- Rats
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Affiliation(s)
- Mahip K Verma
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India.
| | - Rajan N Goel
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Anand M Bokare
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Manoj P Dandekar
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Sarita Koul
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Sagar Desai
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Santoshkumar Tota
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Nilendra Singh
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Prashant B Nigade
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Vinod B Patil
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Dipak Modi
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Maneesh Mehta
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Jayasagar Gundu
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Sameer S Walunj
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Navnath P Karche
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Neelima Sinha
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Rajender K Kamboj
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
| | - Venkata P Palle
- Department of Pharmacology, Novel Drug Discovery and Development, Lupin Limited, Lupin Research Park, Pune, Maharashtra, 412115, India
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9
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Moerke MJ, McMahon LR, Wilkerson JL. More than Smoke and Patches: The Quest for Pharmacotherapies to Treat Tobacco Use Disorder. Pharmacol Rev 2020; 72:527-557. [PMID: 32205338 DOI: 10.1124/pr.119.018028] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Tobacco use is a persistent public health issue. It kills up to half its users and is the cause of nearly 90% of all lung cancers. The main psychoactive component of tobacco is nicotine, primarily responsible for its abuse-related effects. Accordingly, most pharmacotherapies for smoking cessation target nicotinic acetylcholine receptors (nAChRs), nicotine's major site of action in the brain. The goal of the current review is twofold: first, to provide a brief overview of the most commonly used behavioral procedures for evaluating smoking cessation pharmacotherapies and an introduction to pharmacokinetic and pharmacodynamic properties of nicotine important for consideration in the development of new pharmacotherapies; and second, to discuss current and potential future pharmacological interventions aimed at decreasing tobacco use. Attention will focus on the potential for allosteric modulators of nAChRs to offer an improvement over currently approved pharmacotherapies. Additionally, given increasing public concern for the potential health consequences of using electronic nicotine delivery systems, which allow users to inhale aerosolized solutions as an alternative to smoking tobacco, an effort will be made throughout this review to address the implications of this relatively new form of nicotine delivery, specifically as it relates to smoking cessation. SIGNIFICANCE STATEMENT: Despite decades of research that have vastly improved our understanding of nicotine and its effects on the body, only a handful of pharmacotherapies have been successfully developed for use in smoking cessation. Thus, investigation of alternative pharmacological strategies for treating tobacco use disorder remains active; allosteric modulators of nicotinic acetylcholine receptors represent one class of compounds currently under development for this purpose.
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Affiliation(s)
- M J Moerke
- Division of Preclinical Pharmacology, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland (M.J.M.) and Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida (L.R.M., J.L.W.)
| | - L R McMahon
- Division of Preclinical Pharmacology, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland (M.J.M.) and Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida (L.R.M., J.L.W.)
| | - J L Wilkerson
- Division of Preclinical Pharmacology, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland (M.J.M.) and Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida (L.R.M., J.L.W.)
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10
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Allosterism of Nicotinic Acetylcholine Receptors: Therapeutic Potential for Neuroinflammation Underlying Brain Trauma and Degenerative Disorders. Int J Mol Sci 2020; 21:ijms21144918. [PMID: 32664647 PMCID: PMC7404387 DOI: 10.3390/ijms21144918] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/06/2020] [Accepted: 07/10/2020] [Indexed: 12/21/2022] Open
Abstract
Inflammation is a key physiological phenomenon that can be pervasive when dysregulated. Persistent chronic inflammation precedes several pathophysiological conditions forming one of the critical cellular homeostatic checkpoints. With a steady global surge in inflammatory diseases, it is imperative to delineate underlying mechanisms and design suitable drug molecules targeting the cellular partners that mediate and regulate inflammation. Nicotinic acetylcholine receptors have a confirmed role in influencing inflammatory pathways and have been a subject of scientific scrutiny underlying drug development in recent years. Drugs designed to target allosteric sites on the nicotinic acetylcholine receptors present a unique opportunity to unravel the role of the cholinergic system in regulating and restoring inflammatory homeostasis. Such a therapeutic approach holds promise in treating several inflammatory conditions and diseases with inflammation as an underlying pathology. Here, we briefly describe the potential of cholinergic allosterism and some allosteric modulators as a promising therapeutic option for the treatment of neuroinflammation.
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11
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Antonio-Tolentino K, Hopkins CR. Selective α7 nicotinic receptor agonists and positive allosteric modulators for the treatment of schizophrenia - a review. Expert Opin Investig Drugs 2020; 29:603-610. [PMID: 32396418 DOI: 10.1080/13543784.2020.1764938] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
INTRODUCTION Alpha 7 nicotinic acetylcholine receptor (α7 nAChR) partial agonists, agonists, and positive allosteric modulators (PAMs) have been in development for over a decade. The initial candidates were in clinical trials for a wide variety of diseases including schizophrenia, but there has yet to be a successful compound to make it to the market for any disorder. Although difficult to assess the cause of all the clinical failures, the lack of efficacy played a major role. The development of more selective compounds, may bring a successful compound to long-suffering schizophrenia patients. AREAS COVERED This article examines investigational agonists and positive allosteric modulators of the α7 nicotinic receptor in preclinical studies as well as clinical trials. Our search included the use of SciFinder, Google, and clinicaltrials.gov with search dates of 2015 to the present. EXPERT OPINION Researchers must rethink their approach should look more closely at the selectivity of new compounds and how to tackle the translational gap. Perhaps new positive allosteric modulators that can help minimize receptor desensitization and selectivity profiles can be a path forward for α7 nAChRs in schizophrenia.
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Affiliation(s)
- Kirsten Antonio-Tolentino
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center , Omaha, NE, USA
| | - Corey R Hopkins
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center , Omaha, NE, USA
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12
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Unal G, Bekci H, Cumaoglu A, Yerer MB, Aricioglu F. Alpha 7 nicotinic receptor agonist and positive allosteric modulators improved social and molecular deficits of MK-801 model of schizophrenia in rats. Pharmacol Biochem Behav 2020; 193:172916. [PMID: 32220620 DOI: 10.1016/j.pbb.2020.172916] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/20/2020] [Accepted: 03/23/2020] [Indexed: 01/28/2023]
Abstract
Schizophrenia is a common psychiatric disease that cannot be fully treated with current antipsychotic drugs. It has shown that glutamatergic NMDA receptor antagonists such as MK-801 cause schizophrenia-like phenotype in rodents. Recent studies indicated that α7 nicotinic acetylcholine receptor (nAChR) deficits contribute to schizophrenia. Enhancing its activity with agonist or positive allosteric modulators (PAMs) may be a valuable approach for treatment. The certain intracellular pathways such as Akt/Glycogen synthase kinase 3 beta (GSK-3β) and phosphodiesterase-4 (PDE-4)/cAMP are associated with the pathogenesis of schizophrenia. In this study, we examined the effect of α7 nAChR agonists and PAMs on the behavioral and molecular phenotype of schizophrenia in the subchronic MK-801 administered rats. Social interaction, the levels of α7 nAChR, and related intracellular pathways (cAMP, PDE4A, PDE4D, p-Akt/Akt, p-GSK-3β/GSK-3β) were measured by behavioral or ELISA and western blot tests. Subchronic MK-801 administration decreased the following behaviors and increased the avoiding behaviors. However, only α7 nAChR agonist (A-582941) increased the following behavior while α7 nAChR agonist, PAMs (CCMI and PNU-120596), and clozapine decreased the avoiding behavior compared to MK-801. For molecular parameters, MK-801 administration decreased the α7 nAChR, p-Akt/Akt, p-GSK-3β/GSK-3β expressions, and cAMP levels while it increased PDE4A, PDE4D expressions in the prefrontal cortex. Besides, MK-801 decreased the α7 nAChR, p-GSK-3β/GSK-3β expressions in the hippocampus. We found clozapine, α7 nAChR agonists, and PAMs reversed the molecular deficits induced by MK-801. Herein, we showed that prefrontal cortex is more sensitive to the devastating effects of subchronic MK-801 administration, especially for PDE4, in rats. In addition to clozapine, α7 nAChR agonists and PAMs found to be beneficial on both social and molecular deficits induced by MK-801 in rats. We suggested that α7 nAChR agonists and PAMs might be valuable approaches to treat negative symptoms of schizophrenia when unmet needs and current limitations considered in this pathology.
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Affiliation(s)
- G Unal
- Erciyes University, Faculty of Pharmacy, Department of Pharmacology, Kayseri, Turkey
| | - H Bekci
- Kayseri University, Yahyalı Vocational School, Kayseri, Turkey
| | - A Cumaoglu
- Erciyes University, Faculty of Pharmacy, Department of Biochemistry, Kayseri, Turkey
| | - M B Yerer
- Erciyes University, Faculty of Pharmacy, Department of Pharmacology, Kayseri, Turkey
| | - F Aricioglu
- Marmara University, Faculty of Pharmacy, Department of Pharmacology and Psychopharmacology Research Unit, Istanbul, Turkey.
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13
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Jackson A, Alkhlaif Y, Papke RL, Brunzell DH, Damaj MI. Impact of modulation of the α7 nicotinic acetylcholine receptor on nicotine reward in the mouse conditioned place preference test. Psychopharmacology (Berl) 2019; 236:3593-3599. [PMID: 31302720 PMCID: PMC6895411 DOI: 10.1007/s00213-019-05331-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 07/08/2019] [Indexed: 12/26/2022]
Abstract
RATIONALE The α7 nicotinic acetylcholine receptor (nAChR) has been implicated as a target in modulating nicotine reward. However, the effect of pharmacological agents that have been shown to alter the channel properties of the α7 nAChR is not well understood in nicotine reward. OBJECTIVES This study aimed to investigate the impact of α7 nAChR pharmacological modulation on nicotine conditioned place preference (CPP) in mice by using positive allosteric modulators (PAMs) and a silent agonist. METHODS The effect of the orthosteric α7 nAChR full agonist PNU282987 (1.3 and 9 mg/kg, s.c.), Type I α7 PAM NS1738 (1 and 10 mg/kg; i.p.), the Type II α7 PAM PNU120596 (0.3, 1, and 3 mg/kg, i.p.), and the α7 silent agonist NS6740 (1 and 3 mg/kg, i.p) on nicotine CPP was measured in mice. Mice were conditioned with either saline or nicotine (0.5 mg/kg) for 3 days in the CPP paradigm. RESULTS The α7 full orthosteric agonist PNU282987 and the Type II α7 nAChR PAM PNU120596 reduced nicotine CPP, while the silent agonist NS6740 and Type I PAM NS1738 had no effect. The effects of PNU282987 and PNU120596 did not have an effect on morphine CPP. CONCLUSIONS Taken together, our results suggest that modulation of the α7 nAChR can play important roles in nicotine CPP in mice. In addition, the Type II α7 nAChR PAM PNU120596 attenuated nicotine reward suggesting that endogenous acetylcholine/choline tone is sufficient to reduce nicotine CPP. These findings highlight a beneficial effect of using α7 nAChR PAMs in nicotine reward.
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Affiliation(s)
- Asti Jackson
- Department of Psychiatry, Yale School of Medicine, 34 Park St., New Haven, CT, 06519, USA.
| | - Y. Alkhlaif
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298-0613, USA
| | - R. L. Papke
- Department of Pharmacology and Therapeutics, University of Florida, PO Box 100267, Gainesville, FL 32610-0267, USA
| | - D. H. Brunzell
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298-0613, USA
| | - M. I. Damaj
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298-0613, USA
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14
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Li HJ, Sun ZL, Pan YB, Xu MH, Feng DF. Effect of α7nAChR on learning and memory dysfunction in a rat model of diffuse axonal injury. Exp Cell Res 2019; 383:111546. [PMID: 31398352 DOI: 10.1016/j.yexcr.2019.111546] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 08/02/2019] [Accepted: 08/03/2019] [Indexed: 11/30/2022]
Abstract
Diffuse axonal injury (DAI) is the predominant effect of severe traumatic brain injury and significantly contributes to cognitive deficits. The mechanisms that underlie these cognitive deficits are often associated with complex molecular alterations. α7nAChR, one of the abundant and widespread nicotinic acetylcholine receptors (nAChRs) in the brain, plays important physiological functions in the central nervous system. However, the relationship between temporospatial alterations in the α7nAChR and DAI-related learning and memory dysfunction are not completely understood. Our study detected temporospatial alterations of α7nAChR in vulnerable areas (hippocampus, internal capsule, corpus callosum and brain stem) of DAI rats and evaluated the development and progression of learning and memory dysfunction via the Morris water maze (MWM). We determined that α7nAChR expression in vulnerable areas was mainly reduced at the recovery of DAI in rats. Moreover, the escape latency of the injured group increased significantly and the percentages of the distance travelled and time spent in the target quadrant were significantly decreased after DAI. Furthermore, α7nAChR expression in the vulnerable area was significantly positively correlated with MWM performance after DAI according to regression analysis. In addition, we determined that a selective α7nAChR agonist significantly improved learning and memory dysfunction. Rats in the α7nAChR agonist group showed better learning and memory performance than those in the antagonist group. These results demonstrate that microstructural injury-induced alterations of α7nAChR in the vulnerable area are significantly correlated with learning and memory dysfunctions after DAI and that augmentation of the α7nAChR level by its agonist contributes to the improvement of learning and memory function.
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Affiliation(s)
- Hong-Jiang Li
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, 201999, China; Institute of Traumatic Medicine, Shanghai JiaoTong University School of Medicine, Shanghai, 201999, China
| | - Zhao-Liang Sun
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, 201999, China; Institute of Traumatic Medicine, Shanghai JiaoTong University School of Medicine, Shanghai, 201999, China
| | - Yuan-Bo Pan
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, 201999, China
| | - Mang-Hua Xu
- Institute of Traumatic Medicine, Shanghai JiaoTong University School of Medicine, Shanghai, 201999, China
| | - Dong-Fu Feng
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, 201999, China; Institute of Traumatic Medicine, Shanghai JiaoTong University School of Medicine, Shanghai, 201999, China.
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15
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Pesti K, Lukacs P, Mike A. Type I-like behavior of the type II α7 nicotinic acetylcholine receptor positive allosteric modulator A-867744. PeerJ 2019; 7:e7542. [PMID: 31534841 PMCID: PMC6727837 DOI: 10.7717/peerj.7542] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 07/24/2019] [Indexed: 11/24/2022] Open
Abstract
Cognitive impairment often involves the decreased expression or hypofunction of alpha 7-type nicotinic acetylcholine receptors (α7 nAChRs). Agonists or positive allosteric modulators (PAMs) of α7 nAChRs are known to be potential treatments for dementias, different neurodegenerative disorders, pain syndromes and conditions involving inflammation. In some of these conditions, it is desirable to maintain the temporal precision of fast cholinergic events, while in others, this temporal precision is unnecessary. For this reason, the optimal therapeutic effect for distinct indications may require PAMs with different mechanisms of action. The two major mechanisms are called “type I”, which are compounds that augment α7 nAChR-mediated currents but maintain their characteristic fast kinetics; and “type II”, which are compounds that produce augmented and prolonged currents. In this study, we performed a kinetic analysis of two type II PAMs of the α7 nAChR: PNU-120596 and A-867744, using a fast perfusion method that allowed high temporal resolution. We characterized the type of modulation produced by the two compounds, the state-dependence of the modulatory action, and the interaction between the two compounds. We found fundamental differences between the modulation mechanisms by PNU-120596 and A-867744. Most importantly, during brief agonist pulses, A-867744 caused a strikingly type I-like modulation, while PNU-120596 caused a type II-like prolonged activation. Our results demonstrate that specific compounds, even though all labeled as type II PAMs, can behave in completely different ways, including their onset and offset kinetics, state preference, and single channel open time. Our results emphasize that subtle details of the mechanism of action may be significant in assessing the therapeutic applicability of α7 nAChR PAM compounds.
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Affiliation(s)
- Krisztina Pesti
- MTA-ELTE NAP B Opto-Neuropharmacology Group, Eötvös Loránd University, Budapest, Hungary.,Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary.,School of PhD Studies, Semmelweis University, Budapest, Hungary
| | - Peter Lukacs
- Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Martonvásár, Hungary
| | - Arpad Mike
- MTA-ELTE NAP B Opto-Neuropharmacology Group, Eötvös Loránd University, Budapest, Hungary.,Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Martonvásár, Hungary
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16
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Fowler CD, Turner JR, Imad Damaj M. Molecular Mechanisms Associated with Nicotine Pharmacology and Dependence. Handb Exp Pharmacol 2019; 258:373-393. [PMID: 31267166 DOI: 10.1007/164_2019_252] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Tobacco dependence is a leading cause of preventable disease and death worldwide. Nicotine, the main psychoactive component in tobacco cigarettes, has also been garnering increased popularity in its vaporized form, as derived from e-cigarette devices. Thus, an understanding of the molecular mechanisms underlying nicotine pharmacology and dependence is required to ascertain novel approaches to treat drug dependence. In this chapter, we review the field's current understanding of nicotine's actions in the brain, the neurocircuitry underlying drug dependence, factors that modulate the function of nicotinic acetylcholine receptors, and the role of specific genes in mitigating the vulnerability to develop nicotine dependence. In addition to nicotine's direct actions in the brain, other constituents in nicotine and tobacco products have also been found to alter drug use, and thus, evidence is provided to highlight this issue. Finally, currently available pharmacotherapeutic strategies are discussed, along with an outlook for future therapeutic directions to achieve to the goal of long-term nicotine cessation.
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Affiliation(s)
- Christie D Fowler
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA, USA
| | - Jill R Turner
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, USA
| | - M Imad Damaj
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA. .,Translational Research Initiative for Pain and Neuropathy at VCU, Richmond, VA, USA.
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17
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Liu W, Li MD. Insights Into Nicotinic Receptor Signaling in Nicotine Addiction: Implications for Prevention and Treatment. Curr Neuropharmacol 2018; 16:350-370. [PMID: 28762314 PMCID: PMC6018190 DOI: 10.2174/1570159x15666170801103009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 06/18/2017] [Accepted: 07/28/2017] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Nicotinic acetylcholine receptors (nAChRs) belong to the Cys-loop ligandgated ion-channel (LGIC) superfamily, which also includes the GABA, glycine, and serotonin receptors. Many nAChR subunits have been identified and shown to be involved in signal transduction on binding to them of either the neurotransmitter acetylcholine or exogenous ligands such as nicotine. The nAChRs are pentameric assemblies of homologous subunits surrounding a central pore that gates cation flux, and they are expressed at neuromuscular junctions throughout the nervous system. METHODS AND RESULTS Because different nAChR subunits assemble into a variety of pharmacologically distinct receptor subtypes, and different nAChRs are implicated in various physiological functions and pathophysiological conditions, nAChRs represent potential molecular targets for drug addiction and medical therapeutic research. This review intends to provide insights into recent advances in nAChR signaling, considering the subtypes and subunits of nAChRs and their roles in nicotinic cholinergic systems, including structure, diversity, functional allosteric modulation, targeted knockout mutations, and rare variations of specific subunits, and the potency and functional effects of mutations by focusing on their effects on nicotine addiction (NA) and smoking cessation (SC). Furthermore, we review the possible mechanisms of action of nAChRs in NA and SC based on our current knowledge. CONCLUSION Understanding these cellular and molecular mechanisms will lead to better translational and therapeutic operations and outcomes for the prevention and treatment of NA and other drug addictions, as well as chronic diseases, such as Alzheimer's and Parkinson's. Finally, we put forward some suggestions and recommendations for therapy and treatment of NA and other chronic diseases.
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Affiliation(s)
- Wuyi Liu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University School of Medicine, Hangzhou, China.,School of Biological Sciences and Food Engineering, Fuyang Normal University, Fuyang, Anuhi 236041, China
| | - Ming D Li
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University School of Medicine, Hangzhou, China.,Research Center for Air Pollution and Health, Zhejiang University, Hangzhou, China.,Institute of NeuroImmune Pharmacology, Seton Hall University, South Orange, NJ, United States
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18
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Budzynska B, Wnorowski A, Kaszubska K, Biala G, Kruk-Słomka M, Kurzepa J, Boguszewska-Czubara A. Acute MDMA and Nicotine Co-administration: Behavioral Effects and Oxidative Stress Processes in Mice. Front Behav Neurosci 2018; 12:149. [PMID: 30116179 PMCID: PMC6082960 DOI: 10.3389/fnbeh.2018.00149] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Accepted: 06/28/2018] [Indexed: 11/13/2022] Open
Abstract
3,4-Methylenedioxy-methylamphetamine (MDMA), a synthetic substance commonly known as ecstasy, is a worldwide recreational drug of abuse. As MDMA and nicotine activate the same neuronal pathways, we examined the influence of co-administration of nicotine (0.05 mg/kg) and MDMA (1 mg/kg) on cognitive processes, nicotine-induced behavioral sensitization and on processes linked with oxidative stress and α7 nicotinic acetylcholine receptors (nAChRs) expression in the brain of male Swiss mice. For behavioral study the passive avoidance (PA) test and locomotor sensitization paradigm were used. Also, the oxidative stress parameters as well as expression levels of α7 nAChRs in prefrontal cortex and hippocampus of mice treated with MDMA alone or in combination with nicotine were assessed. The results revealed that MDMA injections as well as co-administrations of MDMA and nicotine improved memory consolidation in male Swiss mice tested in PA task. Furthermore, one of the main findings of the present study is that MDMA increased locomotor activity in nicotine-sensitized mice. Our study showed for the first time strong behavioral and biochemical interactions between nicotine and MDMA. Both drugs are very often used in combination, especially by young people, thus these results may help explaining why psychoactive substances are being co-abused and why this polydrug administration is still a social problem.
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Affiliation(s)
- Barbara Budzynska
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Lublin, Poland
| | - Artur Wnorowski
- Department of Biopharmacy, Medical University of Lublin, Lublin, Poland
| | - Katarzyna Kaszubska
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Lublin, Poland
| | - Grazyna Biala
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Lublin, Poland
| | - Marta Kruk-Słomka
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Lublin, Poland
| | - Jacek Kurzepa
- Department of Medical Chemistry, Medical University of Lublin, Lublin, Poland
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19
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Mendoza C, Barreto GE, Iarkov A, Tarasov VV, Aliev G, Echeverria V. Cotinine: A Therapy for Memory Extinction in Post-traumatic Stress Disorder. Mol Neurobiol 2018; 55:6700-6711. [PMID: 29335846 DOI: 10.1007/s12035-018-0869-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 01/07/2018] [Indexed: 12/14/2022]
Abstract
Post-traumatic stress disorder (PTSD) is a mental disorder that may develop after exposure to exceptionally threatening or unescapable horrifying events. Actual therapies fail to alleviate the emotional suffering and cognitive impairment associated with this disorder, mostly because they are ineffective in treating the failure to extinguish trauma memories in a great percentage of those affected. In this review, current behavioral, cellular, and molecular evidence supporting the use of cotinine for treating PTSD are reviewed. The role of the positive modulation by cotinine of the nicotinic acetylcholine receptors (nAChRs) and their downstream effectors, the protection of astroglia, and the inhibition of microglia in the PTSD brain are also discussed.
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Affiliation(s)
- Cristhian Mendoza
- Facultad de Ciencias de la Salud, Universidad San Sebastián, Lientur 1457, 4030000, Concepción, Chile
| | - George E Barreto
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia.,Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Alexandre Iarkov
- Facultad de Ciencias de la Salud, Universidad San Sebastián, Lientur 1457, 4030000, Concepción, Chile
| | - Vadim V Tarasov
- Institute of Pharmacy and Translational Medicine, Sechenov First Moscow State Medical University, 119991, Moscow, Russia
| | - Gjumrakch Aliev
- Institute of Physiologically Active Compounds of the Russian Academy of Sciences, Severniy Proezd, Chernogolovka, Moscow Region, 1142432, Russia. .,"GALLY" International Biomedical Research Consulting LLC, San Antonio, TX, 78229, USA. .,School of Health Sciences and Healthcare Administration, University of Atlanta, Johns Creek, GA, 30097, USA.
| | - Valentina Echeverria
- Facultad de Ciencias de la Salud, Universidad San Sebastián, Lientur 1457, 4030000, Concepción, Chile. .,Bay Pines VA Healthcare System, Research and Development, Bay Pines, FL, 33744, USA.
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20
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Unal G, Aricioglu F. A-582941, cholinergic alpha 7 nicotinic receptor agonist, improved cognitive and negative symptoms of the sub-chronic MK-801 model of schizophrenia in rats. PSYCHIAT CLIN PSYCH 2017. [DOI: 10.1080/24750573.2017.1379716] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Affiliation(s)
- Gokhan Unal
- Faculty of Pharmacy, Department of Pharmacology and Psychopharmacology Research Unit, Marmara University, Istanbul, Turkey
| | - Feyza Aricioglu
- Faculty of Pharmacy, Department of Pharmacology and Psychopharmacology Research Unit, Marmara University, Istanbul, Turkey
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21
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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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22
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Wichern F, Jensen MM, Christensen DZ, Mikkelsen JD, Gondré-Lewis MC, Thomsen MS. Perinatal nicotine treatment induces transient increases in NACHO protein levels in the rat frontal cortex. Neuroscience 2017; 346:278-283. [PMID: 28131622 DOI: 10.1016/j.neuroscience.2017.01.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 01/13/2017] [Accepted: 01/16/2017] [Indexed: 12/16/2022]
Abstract
The nicotinic acetylcholine receptor (nAChR) regulator chaperone (NACHO) was recently identified as an important regulator of nAChR maturation and surface expression. Here we show that NACHO levels decrease during early postnatal development in rats. This decrease occurs earlier and to a greater degree in the frontal cortex (FC) compared with the hippocampus (HIP). We further show that rats exposed to nicotine during pre- and postnatal development exhibit significantly higher NACHO levels in the FC at postnatal day (PND) 21, but not at PND60. Repeated exposure to nicotine selectively during early (PND8-14) or late (PND54-60) postnatal stages did not affect NACHO protein levels in the FC or HIP, neither did exposure to high doses of the selective α7 nAChR agonists SSR180711, A-582941, or PNU-282987. However, we found significantly increased NACHO protein levels in the FC of PND36 rats after a single exposure to a combination of nicotine and the type II α7 nAChR positive allosteric modulator (PAM) PNU-120596, but not the type I PAM AVL-3288. These findings suggest that exposure to nAChR agonism affects NACHO protein levels, and that this effect is more pronounced during pre- or early postnatal development. The effect of PNU-120596 further suggests that the increase in NACHO expression is caused by activation rather than desensitization of nAChRs.
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Affiliation(s)
- Franziska Wichern
- Department of Drug Design & Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Majbrit M Jensen
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Ditte Z Christensen
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Jens D Mikkelsen
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Marjorie C Gondré-Lewis
- Laboratory for Neurodevelopment, Department of Anatomy, Howard University College of Medicine, Washington D.C., USA; Neuropsychopharmacology Laboratory, Dept. of Psychiatry and Behavioral Sciences, Howard University College of Medicine, Washington D.C., USA
| | - Morten S Thomsen
- Department of Drug Design & Pharmacology, University of Copenhagen, Copenhagen, Denmark.
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23
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Corradi J, Bouzat C. Understanding the Bases of Function and Modulation of α7 Nicotinic Receptors: Implications for Drug Discovery. Mol Pharmacol 2016; 90:288-99. [PMID: 27190210 DOI: 10.1124/mol.116.104240] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 05/05/2016] [Indexed: 01/01/2023] Open
Abstract
The nicotinic acetylcholine receptor (nAChR) belongs to a superfamily of pentameric ligand-gated ion channels involved in many physiologic and pathologic processes. Among nAChRs, receptors comprising the α7 subunit are unique because of their high Ca(2+) permeability and fast desensitization. nAChR agonists elicit a transient ion flux response that is further sustained by the release of calcium from intracellular sources. Owing to the dual ionotropic/metabotropic nature of α7 receptors, signaling pathways are activated. The α7 subunit is highly expressed in the nervous system, mostly in regions implicated in cognition and memory and has therefore attracted attention as a novel drug target. Additionally, its dysfunction is associated with several neuropsychiatric and neurologic disorders, such as schizophrenia and Alzheimer's disease. α7 is also expressed in non-neuronal cells, particularly immune cells, where it plays a role in immunity, inflammation, and neuroprotection. Thus, α7 potentiation has emerged as a therapeutic strategy for several neurologic and inflammatory disorders. With unique activation properties, the receptor is a sensitive drug target carrying different potential binding sites for chemical modulators, particularly agonists and positive allosteric modulators. Although macroscopic and single-channel recordings have provided significant information about the underlying molecular mechanisms and binding sites of modulatory compounds, we know just the tip of the iceberg. Further concerted efforts are necessary to effectively exploit α7 as a drug target for each pathologic situation. In this article, we focus mainly on the molecular basis of activation and drug modulation of α7, key pillars for rational drug design.
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Affiliation(s)
- Jeremías Corradi
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Universidad Nacional del Sur, CONICET/UNS, Bahía Blanca, Argentina
| | - Cecilia Bouzat
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Universidad Nacional del Sur, CONICET/UNS, Bahía Blanca, Argentina
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Targowska-Duda KM, Wnorowski A, Budzynska B, Jozwiak K, Biala G, Arias HR. The positive allosteric modulator of α7 nicotinic acetylcholine receptors, 3-furan-2-yl-N-p-tolyl-acrylamide, enhances memory processes and stimulates ERK1/2 phosphorylation in mice. Behav Brain Res 2016; 302:142-51. [DOI: 10.1016/j.bbr.2016.01.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 12/31/2015] [Accepted: 01/04/2016] [Indexed: 02/06/2023]
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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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Sadigh-Eteghad S, Talebi M, Mahmoudi J, Babri S, Shanehbandi D. Selective activation of α7 nicotinic acetylcholine receptor by PHA-543613 improves Aβ25–35-mediated cognitive deficits in mice. Neuroscience 2015; 298:81-93. [DOI: 10.1016/j.neuroscience.2015.04.017] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 04/07/2015] [Accepted: 04/08/2015] [Indexed: 12/22/2022]
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Chalcones as positive allosteric modulators of α7 nicotinic acetylcholine receptors: A new target for a privileged structure. Eur J Med Chem 2014; 86:724-39. [DOI: 10.1016/j.ejmech.2014.09.039] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 09/09/2014] [Accepted: 09/11/2014] [Indexed: 12/26/2022]
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Grizzell JA, Echeverria V. New Insights into the Mechanisms of Action of Cotinine and its Distinctive Effects from Nicotine. Neurochem Res 2014; 40:2032-46. [PMID: 24970109 DOI: 10.1007/s11064-014-1359-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 06/10/2014] [Indexed: 12/20/2022]
Abstract
Tobacco consumption is far higher among a number of psychiatric and neurological diseases, supporting the notion that some component(s) of tobacco may underlie the oft-reported reduction in associated symptoms during tobacco use. Popular dogma holds that this component is nicotine. However, increasing evidence support theories that cotinine, the main metabolite of nicotine, may underlie at least some of nicotine's actions in the nervous system, apart from its adverse cardiovascular and habit forming effects. Though similarities exist, disparate and even antagonizing actions between cotinine and nicotine have been described both in terms of behavior and physiology, underscoring the need to further characterize this potentially therapeutic compound. Cotinine has been shown to be psychoactive in humans and animals, facilitating memory, cognition, executive function, and emotional responding. Furthermore, recent research shows that cotinine acts as an antidepressant and reduces cognitive-impairment associated with disease and stress-induced dysfunction. Despite these promising findings, continued focus on this potentially safe alternative to tobacco and nicotine use is lacking. Here, we review the effects of cotinine, including comparisons with nicotine, and discuss potential mechanisms of cotinine-specific actions in the central nervous system which are, to date, still being elucidated.
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Affiliation(s)
- J Alex Grizzell
- Department of Psychiatry and Behavioral Neurosciences, Morsani College of Medicine, University of South Florida, Tampa, FL, 33611, USA.,Department of Research and Development, Bay Pines VA Healthcare System, 10,000 Bay Pines Blvd., Bldg. 23, Rm. 123, Bay Pines, FL, 33744, USA
| | - Valentina Echeverria
- Department of Research and Development, Bay Pines VA Healthcare System, 10,000 Bay Pines Blvd., Bldg. 23, Rm. 123, Bay Pines, FL, 33744, USA. .,Universidad Autónoma de Chile, Carlos Antúnez 1920, Providencia, Santiago, Chile. .,Department of Molecular Medicine, University of South Florida, Tampa, FL, 33647, USA.
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Involvement of α7 nAChR subtype in rat oxaliplatin-induced neuropathy: Effects of selective activation. Neuropharmacology 2014; 79:37-48. [DOI: 10.1016/j.neuropharm.2013.10.034] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 10/14/2013] [Accepted: 10/28/2013] [Indexed: 12/12/2022]
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Perinatal hypoxia-ischemia reduces α 7 nicotinic receptor expression and selective α 7 nicotinic receptor stimulation suppresses inflammation and promotes microglial Mox phenotype. BIOMED RESEARCH INTERNATIONAL 2014; 2014:718769. [PMID: 24757672 PMCID: PMC3976804 DOI: 10.1155/2014/718769] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 01/30/2014] [Accepted: 01/30/2014] [Indexed: 11/17/2022]
Abstract
Inflammation plays a central role in neonatal brain injury. During brain inflammation the resident macrophages of the brain, the microglia cells, are rapidly activated. In the periphery, α7 nicotinic acetylcholine receptors (α7R) present on macrophages can regulate inflammation by suppressing cytokine release. In the current study we investigated α7R expression in neonatal mice after hypoxia-ischemia (HI). We further examined possible anti-inflammatory role of α7R stimulation in vitro and microglia polarization after α7R agonist treatment. Real-time PCR analysis showed a 33% reduction in α7R expression 72 h after HI. Stimulation of primary microglial cells with LPS in combination with increasing doses of the selective α7R agonist AR-R 17779 significantly attenuated TNFα release and increased α7R transcript in microglial cells. Gene expression of M1 markers CD86 and iNOS, as well as M2 marker CD206 was not influenced by LPS and/or α7R agonist treatment. Further, Mox markers heme oxygenase (Hmox1) and sulforedoxin-1 (Srx1) were significantly increased, suggesting a polarization towards the Mox phenotype after α7R stimulation. Thus, our data suggest a role for the α7R also in the neonatal brain and support the anti-inflammatory role of α7R in microglia, suggesting that α7R stimulation could enhance the polarization towards a reparative Mox phenotype.
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Young JW, Geyer MA. Evaluating the role of the alpha-7 nicotinic acetylcholine receptor in the pathophysiology and treatment of schizophrenia. Biochem Pharmacol 2013; 86:1122-32. [PMID: 23856289 DOI: 10.1016/j.bcp.2013.06.031] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 06/27/2013] [Accepted: 06/28/2013] [Indexed: 12/16/2022]
Abstract
The group of schizophrenia disorders affects approximately 1% of the population and has both genetic and environmental etiologies. Sufferers report various behavioral abnormalities including hallucinations and delusions (positive symptoms), reduced joy and amotivation (negative symptoms), plus inattention and poor learning (cognitive deficits). Despite the heterogeneous symptoms experienced, most patients smoke. The self-medication hypothesis posits that patients smoke to alleviate symptoms, consistent with evidence for nicotine-induced enhancement of cognition. While nicotine acts on multiple nicotinic acetylcholine receptors (nAChRs), the primary target of research is often the homomeric α7 nAChR. Given genetic linkages between schizophrenia and this receptor, its association with P50 sensory gating deficits, and its reduced expression in post-mortem brains, many have attempted to develop α7 nAChR ligands for treating schizophrenia. Recent evidence that ligands can be orthosteric agonists or positive allosteric modulators (PAMs) has revitalized the hope for treatment discovery. Herein, we present evidence regarding: (1) pathophysiological alterations of α7 nAChRs that might occur in patients; (2) mechanistic evidence for the normal action of α7 nAChRs; (3) preclinical studies using α7 nAChR orthosteric agonists and type I/II PAMs; and (4) where successful translational testing has occurred for particular compounds, detailing what is still required. We report that the accumulating evidence is positive, but that greater work is required using positron emission tomography to understand current alterations in α7 nAChR expression and their relationship to symptoms. Finally, cross-species behavioral tasks should be used more regularly to determine the predictive efficacy of treatments.
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Affiliation(s)
- Jared W Young
- Department of Psychiatry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0804, United States; Research Service, San Diego Veteran's Affairs Hospital, 3350 La Jolla Drive, San Diego, CA 92037, United States.
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Yakel JL. Cholinergic receptors: functional role of nicotinic ACh receptors in brain circuits and disease. Pflugers Arch 2013; 465:441-50. [PMID: 23307081 PMCID: PMC3633680 DOI: 10.1007/s00424-012-1200-1] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 12/03/2012] [Accepted: 12/03/2012] [Indexed: 12/13/2022]
Abstract
The neurotransmitter acetylcholine (ACh) can regulate neuronal excitability throughout the nervous system by acting on both the cys-loop ligand-gated nicotinic ACh receptor channels (nAChRs) and the G protein-coupled muscarinic ACh receptors (mAChRs). The hippocampus is an important area in the brain for learning and memory, where both nAChRs and mAChRs are expressed. The primary cholinergic input to the hippocampus arises from the medial septum and diagonal band of Broca, the activation of which can activate both nAChRs and mAChRs in the hippocampus and regulate synaptic communication and induce oscillations that are thought to be important for cognitive function. Dysfunction in the hippocampal cholinergic system has been linked with cognitive deficits and a variety of neurological disorders and diseases, including Alzheimer's disease and schizophrenia. My lab has focused on the role of the nAChRs in regulating hippocampal function, from understanding the expression and functional properties of the various subtypes of nAChRs, and what role these receptors may be playing in regulating synaptic plasticity. Here, I will briefly review this work, and where we are going in our attempts to further understand the role of these receptors in learning and memory, as well as in disease and neuroprotection.
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Affiliation(s)
- Jerrel L Yakel
- Laboratory of Neurobiology, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, P.O. Box 12233, Mail Drop F2-08, Research Triangle Park, NC 27709, USA.
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