1
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Tan X, Neslund EM, Fentis K, Ding ZM. Fluorocitrate inhibition of astrocytes reduces nicotine self-administration and alters extracellular levels of glutamate and dopamine within the nucleus accumbens in male wistar rats. Neuropharmacology 2024; 255:110001. [PMID: 38750804 PMCID: PMC11156530 DOI: 10.1016/j.neuropharm.2024.110001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 05/10/2024] [Accepted: 05/11/2024] [Indexed: 05/25/2024]
Abstract
Emerging evidence suggests an important role of astrocytes in mediating behavioral and molecular effects of commonly misused drugs. Passive exposure to nicotine alters molecular, morphological, and functional properties of astrocytes. However, a potential involvement of astrocytes in nicotine reinforcement remains largely unexplored. The overall hypothesis tested in the current study is that astrocytes play a critical role in nicotine reinforcement. Protein levels of the astrocyte marker glial fibrillary acidic protein (GFAP) were examined in key mesocorticolimbic regions following chronic nicotine intravenous self-administration. Fluorocitrate, a metabolic inhibitor of astrocytes, was tested for its effects on behaviors related to nicotine reinforcement and relapse. Effects of fluorocitrate on extracellular neurotransmitter levels, including glutamate, GABA, and dopamine, were determined with microdialysis. Chronic nicotine intravenous self-administration increased GFAP expression in the nucleus accumbens core (NACcr), but not other key mesocorticolimbic regions, compared to saline intravenous self-administration. Both intra-ventricular and intra-NACcr microinjection of fluorocitrate decreased nicotine self-administration. Intra-NACcr fluorocitrate microinjection also inhibited cue-induced reinstatement of nicotine seeking. Local perfusion of fluorocitrate decreased extracellular glutamate levels, elevated extracellular dopamine levels, but did not alter extracellular GABA levels in the NACcr. Fluorocitrate did not alter basal locomotor activity. These results indicate that nicotine reinforcement upregulates the astrocyte marker GFAP expression in the NACcr, metabolic inhibition of astrocytes attenuates nicotine reinforcement and relapse, and metabolic inhibition of astrocytes disrupts extracellular dopamine and glutamate transmission. Overall, these findings suggest that astrocytes play an important role in nicotine reinforcement and relapse, potentially through regulation of extracellular glutamate and dopamine neurotransmission.
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Affiliation(s)
- Xiaoying Tan
- Department of Anesthesiology & Perioperative Medicine, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Elizabeth M Neslund
- Department of Anesthesiology & Perioperative Medicine, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Khawla Fentis
- Department of Anesthesiology & Perioperative Medicine, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Zheng-Ming Ding
- Department of Anesthesiology & Perioperative Medicine, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA; Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA.
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2
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Chen SH, Damborsky JC, Wilson BC, Fannin RD, Ward JM, Gerrish KE, He B, Martin NP, Yakel JL. α7 nicotinic receptor activation mitigates herpes simplex virus type 1 infection in microglia cells. Antiviral Res 2024; 228:105934. [PMID: 38880195 PMCID: PMC11250235 DOI: 10.1016/j.antiviral.2024.105934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 05/20/2024] [Accepted: 06/13/2024] [Indexed: 06/18/2024]
Abstract
Herpes simplex virus type 1 (HSV-1), a neurotropic DNA virus, establishes latency in neural tissues, with reactivation causing severe consequences like encephalitis. Emerging evidence links HSV-1 infection to chronic neuroinflammation and neurodegenerative diseases. Microglia, the central nervous system's (CNS) immune sentinels, express diverse receptors, including α7 nicotinic acetylcholine receptors (α7 nAChRs), critical for immune regulation. Recent studies suggest α7 nAChR activation protects against viral infections. Here, we show that α7 nAChR agonists, choline and PNU-282987, significantly inhibit HSV-1 replication in microglial BV2 cells. Notably, this inhibition is independent of the traditional ionotropic nAChR signaling pathway. mRNA profiling revealed that choline stimulates the expression of antiviral factors, IL-1β and Nos2, and down-regulates the apoptosis genes and type A Lamins in BV2 cells. These findings suggest a novel mechanism by which microglial α7 nAChRs restrict viral infections by regulating innate immune responses.
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Affiliation(s)
- Shih-Heng Chen
- Viral Vector Core Facility, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA; Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Joanne C Damborsky
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Belinda C Wilson
- Viral Vector Core Facility, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA; Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Rick D Fannin
- Molecular Genomics Core Facility, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, USA
| | - James M Ward
- Bioinformatics Support Group, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, USA
| | - Kevin E Gerrish
- Molecular Genomics Core Facility, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, USA
| | - Bo He
- Viral Vector Core Facility, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA; Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Negin P Martin
- Viral Vector Core Facility, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA; Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Jerrel L Yakel
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA.
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3
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Abbondanza A, Urushadze A, Alves-Barboza AR, Janickova H. Expression and function of nicotinic acetylcholine receptors in specific neuronal populations: Focus on striatal and prefrontal circuits. Pharmacol Res 2024; 204:107190. [PMID: 38704107 DOI: 10.1016/j.phrs.2024.107190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 04/19/2024] [Accepted: 04/20/2024] [Indexed: 05/06/2024]
Abstract
Nicotinic acetylcholine receptors (nAChRs) are widely expressed in the central nervous system and play an important role in the control of neural functions including neuronal activity, transmitter release and synaptic plasticity. Although the common subtypes of nAChRs are abundantly expressed throughout the brain, their expression in different brain regions and by individual neuronal types is not homogeneous or incidental. In recent years, several studies have emerged showing that particular subtypes of nAChRs are expressed by specific neuronal populations in which they have major influence on the activity of local circuits and behavior. It has been demonstrated that even nAChRs expressed by relatively rare neuronal types can induce significant changes in behavior and contribute to pathological processes. Depending on the identity and connectivity of the particular nAChRs-expressing neuronal populations, the activation of nAChRs can have distinct or even opposing effects on local neuronal signaling. In this review, we will summarize the available literature describing the expression of individual nicotinic subunits by different neuronal types in two crucial brain regions, the striatum and the prefrontal cortex. The review will also briefly discuss nicotinic expression in non-neuronal, glial cells, as they cannot be ignored as potential targets of nAChRs-modulating drugs. The final section will discuss options that could allow us to target nAChRs in a neuronal-type-specific manner, not only in the experimental field, but also eventually in clinical practice.
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Affiliation(s)
- Alice Abbondanza
- Laboratory of Neurochemistry, Institute of Physiology of the Czech Academy of Sciences, Prague 14200, Czech Republic
| | - Anna Urushadze
- Laboratory of Neurochemistry, Institute of Physiology of the Czech Academy of Sciences, Prague 14200, Czech Republic
| | - Amanda Rosanna Alves-Barboza
- Laboratory of Neurochemistry, Institute of Physiology of the Czech Academy of Sciences, Prague 14200, Czech Republic
| | - Helena Janickova
- Laboratory of Neurochemistry, Institute of Physiology of the Czech Academy of Sciences, Prague 14200, Czech Republic.
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4
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Caban KM, Seßenhausen P, Stöckl JB, Popper B, Mayerhofer A, Fröhlich T. Proteome profile of the cerebellum from α7 nicotinic acetylcholine receptor deficient mice. Proteomics 2024; 24:e2300384. [PMID: 38185761 DOI: 10.1002/pmic.202300384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/09/2024]
Abstract
The alpha7 nicotinic acetylcholine receptor (α7 nAChR; CHRNA7) is expressed in the nervous system and in non-neuronal tissues. Within the central nervous system, it is involved in various cognitive and sensory processes such as learning, attention, and memory. It is also expressed in the cerebellum, where its roles are; however, not as well understood as in the other brain regions. To investigate the consequences of absence of CHRNA7 on the cerebellum proteome, we performed a quantitative nano-LC-MS/MS analysis of samples from CHRNA7 knockout (KO) mice and corresponding wild type (WT) controls. Liver, an organ which does not express this receptor, was analyzed, in comparison. While the liver proteome remained relatively unaltered (three proteins more abundant in KOs), 90 more and 20 less abundant proteins were detected in the cerebellum proteome of the KO mice. The gene ontology analysis of the differentially abundant proteins indicates that the absence of CHRNA7 leads to alterations in the glutamatergic system and myelin sheath in the cerebellum. In conclusion, our dataset provides new insights in the role of CHRNA7 in the cerebellum, which may serve as a basis for future in depth-investigations.
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Affiliation(s)
| | - Pia Seßenhausen
- Biomedical Center Munich (BMC), Cell Biology, Anatomy III, Faculty of Medicine, Ludwig Maximilian University of Munich, Planegg-Martinsried, Germany
| | - Jan Bernard Stöckl
- Laboratory for Functional Genome Analysis LAFUGA, Gene Center, LMU München, München, Germany
| | - Bastian Popper
- Biomedical Center (BMC), Core Facility Animal Models, Faculty of Medicine, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
| | - Artur Mayerhofer
- Biomedical Center Munich (BMC), Cell Biology, Anatomy III, Faculty of Medicine, Ludwig Maximilian University of Munich, Planegg-Martinsried, Germany
| | - Thomas Fröhlich
- Laboratory for Functional Genome Analysis LAFUGA, Gene Center, LMU München, München, Germany
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5
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Ihnatovych I, Saddler RA, Sule N, Szigeti K. Translational implications of CHRFAM7A, an elusive human-restricted fusion gene. Mol Psychiatry 2024; 29:1020-1032. [PMID: 38200291 PMCID: PMC11176066 DOI: 10.1038/s41380-023-02389-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 12/08/2023] [Accepted: 12/15/2023] [Indexed: 01/12/2024]
Abstract
Genes restricted to humans may contribute to human-specific traits and provide a different context for diseases. CHRFAM7A is a uniquely human fusion gene and a negative regulator of the α7 nicotinic acetylcholine receptor (α7 nAChR). The α7 nAChR has been a promising target for diseases affecting cognition and higher cortical functions, however, the treatment effect observed in animal models failed to translate into human clinical trials. As CHRFAM7A was not accounted for in preclinical drug screens it may have contributed to the translational gap. Understanding the complex genetic architecture of the locus, deciphering the functional impact of CHRFAM7A on α7 nAChR neurobiology and utilizing human-relevant models may offer novel approaches to explore α7 nAChR as a drug target.
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Affiliation(s)
- Ivanna Ihnatovych
- Department of Neurology, State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Ruth-Ann Saddler
- Department of Neurology, State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Norbert Sule
- Roswell Park Comprehensive Cancer Center, 665 Elm St, Buffalo, NY, 14203, USA
| | - Kinga Szigeti
- Department of Neurology, State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA.
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6
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Burke SM, Avstrikova M, Noviello CM, Mukhtasimova N, Changeux JP, Thakur GA, Sine SM, Cecchini M, Hibbs RE. Structural mechanisms of α7 nicotinic receptor allosteric modulation and activation. Cell 2024; 187:1160-1176.e21. [PMID: 38382524 PMCID: PMC10950261 DOI: 10.1016/j.cell.2024.01.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 12/05/2023] [Accepted: 01/22/2024] [Indexed: 02/23/2024]
Abstract
The α7 nicotinic acetylcholine receptor is a pentameric ligand-gated ion channel that plays an important role in cholinergic signaling throughout the nervous system. Its unique physiological characteristics and implications in neurological disorders and inflammation make it a promising but challenging therapeutic target. Positive allosteric modulators overcome limitations of traditional α7 agonists, but their potentiation mechanisms remain unclear. Here, we present high-resolution structures of α7-modulator complexes, revealing partially overlapping binding sites but varying conformational states. Structure-guided functional and computational tests suggest that differences in modulator activity arise from the stable rotation of a channel gating residue out of the pore. We extend the study using a time-resolved cryoelectron microscopy (cryo-EM) approach to reveal asymmetric state transitions for this homomeric channel and also find that a modulator with allosteric agonist activity exploits a distinct channel-gating mechanism. These results define mechanisms of α7 allosteric modulation and activation with implications across the pentameric receptor superfamily.
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Affiliation(s)
- Sean M Burke
- Molecular Biophysics Graduate Program, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Mariia Avstrikova
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, 67081 Strasbourg Cedex, France
| | - Colleen M Noviello
- Department of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Nuriya Mukhtasimova
- Receptor Biology Laboratory, Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, MN 55902, USA; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN 55902, USA
| | - Jean-Pierre Changeux
- Neuroscience Department, Institut Pasteur, Collège de France, 75015 Paris, France
| | - Ganesh A Thakur
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA
| | - Steven M Sine
- Receptor Biology Laboratory, Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, MN 55902, USA; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN 55902, USA; Department of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55902, USA.
| | - Marco Cecchini
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, 67081 Strasbourg Cedex, France.
| | - Ryan E Hibbs
- Department of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA; Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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7
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Lopes PKF, Costa SDO, Simino LADP, Chaves WF, Silva FA, Costa CL, Milanski M, Ignacio-Souza LM, Torsoni AS, Torsoni MA. Hypothalamic inflammation and the development of an obese phenotype induced by high-fat diet consumption is exacerbated in alpha7 nicotinic cholinergic receptor knockout mice. Food Res Int 2024; 176:113808. [PMID: 38163714 DOI: 10.1016/j.foodres.2023.113808] [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: 09/14/2023] [Revised: 11/27/2023] [Accepted: 12/02/2023] [Indexed: 01/03/2024]
Abstract
Hypothalamic inflammation and metabolic changes resulting from the consumption of high-fat diets have been linked to low grade inflammation and obesity. Inflammation impairs the hypothalamic expression of α7 nicotinic acetylcholine receptor (α7nAChR). The α7nAChR is described as the main component of the anti-inflammatory cholinergic pathway in different inflammation models. To assess whether the reduction in α7nAChR expression exacerbates hypothalamic inflammation induced by a high-fat diet (HFD), were used male and female global α7nAChR knockout mouse line in normal or high-fat diet for 4 weeks. Body weight gain, adiposity, glucose homeostasis, hypothalamic inflammation, food intake, and energy expenditure were evaluated. Insulin sensitivity was evaluated in neuronal cell culture. Consumption of an HFD for 4 weeks resulted in body weight gain and adiposity in male Chrna7-/- mice and the hypothalamus of male Chrna7-/- mice showed neuroinflammatory markers, with increased gene expression of pro-inflammatory cytokines and dysregulation in the nuclear factor kappa B pathway. Moreover, male Chrna7-/- mice consuming an HFD showed alterations in glucose homeostasis and serum of Chrna7-/- mice that consumed an HFD impaired insulin signalling in neuronal cell culture experiments. In general, female Chrna7-/- mice that consumed an HFD did not show the phenotypic and molecular changes found in male mice, indicating that there is sexual dimorphism in the analysed parameters. Thus, receptor deletion resulted in increased susceptibility to hypothalamic inflammation and metabolic damage associated with HFD consumption in male mice.
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Affiliation(s)
| | - Suleyma de Oliveira Costa
- Laboratory of Metabolic Disorders (Labdime), School of Applied Sciences, University of Campinas (UNICAMP), Brazil
| | - Laís A de Paula Simino
- Laboratory of Metabolic Disorders (Labdime), School of Applied Sciences, University of Campinas (UNICAMP), Brazil
| | - Wenicios Ferreira Chaves
- Laboratory of Metabolic Disorders (Labdime), School of Applied Sciences, University of Campinas (UNICAMP), Brazil
| | - Franciely Alves Silva
- Laboratory of Metabolic Disorders (Labdime), School of Applied Sciences, University of Campinas (UNICAMP), Brazil
| | - Caroline Lobo Costa
- Laboratory of Metabolic Disorders (Labdime), School of Applied Sciences, University of Campinas (UNICAMP), Brazil
| | - Marciane Milanski
- Laboratory of Metabolic Disorders (Labdime), School of Applied Sciences, University of Campinas (UNICAMP), Brazil; Obesity and Comorbidities Research Center, University of Campinas (UNICAMP), Brazil
| | - Leticia Martins Ignacio-Souza
- Laboratory of Metabolic Disorders (Labdime), School of Applied Sciences, University of Campinas (UNICAMP), Brazil; Obesity and Comorbidities Research Center, University of Campinas (UNICAMP), Brazil
| | - Adriana Souza Torsoni
- Laboratory of Metabolic Disorders (Labdime), School of Applied Sciences, University of Campinas (UNICAMP), Brazil; Obesity and Comorbidities Research Center, University of Campinas (UNICAMP), Brazil
| | - Marcio Alberto Torsoni
- Laboratory of Metabolic Disorders (Labdime), School of Applied Sciences, University of Campinas (UNICAMP), Brazil; Obesity and Comorbidities Research Center, University of Campinas (UNICAMP), Brazil.
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8
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Sinclair P, Kabbani N. Ionotropic and metabotropic responses by alpha 7 nicotinic acetylcholine receptors. Pharmacol Res 2023; 197:106975. [PMID: 38032294 DOI: 10.1016/j.phrs.2023.106975] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/12/2023] [Accepted: 10/26/2023] [Indexed: 12/01/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) belong to a superfamily of cys-loop receptors characterized by the assembly of five subunits into a multi-protein channel complex. Ligand binding to nAChRs activates rapid allosteric transitions of the receptor leading to channel opening and ion flux in neuronal and non-neuronal cell. Thus, while ionotropic properties of nAChRs are well recognized, less is known about ligand-mediated intracellular metabotropic signaling responses. Studies in neural and non-neural cells confirm ionotropic and metabotropic channel responses following ligand binding. In this review we summarize evidence on the existence of ionotropic and metabotropic signaling responses by homopentameric α7 nAChRs in various cell types. We explore how coordinated calcium entry through the ion channel and calcium release from nearby stores gives rise to signaling important for the modulation of cytoskeletal motility and cell growth. Amino acid residues for intracellular protein binding within the α7 nAChR support engagement in metabotropic responses including signaling through heterotrimeric G proteins in neural and immune cells. Understanding the dual properties of ionotropic and metabotropic nAChR responses is essential in advancing drug development for the treatment of various human disease.
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Affiliation(s)
| | - Nadine Kabbani
- Interdisciplinary Program in Neuroscience, Fairfax, VA, USA; School of Systems Biology, George Mason University, Fairfax, VA, USA.
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9
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Lia A, Di Spiezio A, Vitalini L, Tore M, Puja G, Losi G. Ion Channels and Ionotropic Receptors in Astrocytes: Physiological Functions and Alterations in Alzheimer's Disease and Glioblastoma. Life (Basel) 2023; 13:2038. [PMID: 37895420 PMCID: PMC10608464 DOI: 10.3390/life13102038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/03/2023] [Accepted: 10/07/2023] [Indexed: 10/29/2023] Open
Abstract
The human brain is composed of nearly one hundred billion neurons and an equal number of glial cells, including macroglia, i.e., astrocytes and oligodendrocytes, and microglia, the resident immune cells of the brain. In the last few decades, compelling evidence has revealed that glial cells are far more active and complex than previously thought. In particular, astrocytes, the most abundant glial cell population, not only take part in brain development, metabolism, and defense against pathogens and insults, but they also affect sensory, motor, and cognitive functions by constantly modulating synaptic activity. Not surprisingly, astrocytes are actively involved in neurodegenerative diseases (NDs) and other neurological disorders like brain tumors, in which they rapidly become reactive and mediate neuroinflammation. Reactive astrocytes acquire or lose specific functions that differently modulate disease progression and symptoms, including cognitive impairments. Astrocytes express several types of ion channels, including K+, Na+, and Ca2+ channels, transient receptor potential channels (TRP), aquaporins, mechanoreceptors, and anion channels, whose properties and functions are only partially understood, particularly in small processes that contact synapses. In addition, astrocytes express ionotropic receptors for several neurotransmitters. Here, we provide an extensive and up-to-date review of the roles of ion channels and ionotropic receptors in astrocyte physiology and pathology. As examples of two different brain pathologies, we focus on Alzheimer's disease (AD), one of the most diffuse neurodegenerative disorders, and glioblastoma (GBM), the most common brain tumor. Understanding how ion channels and ionotropic receptors in astrocytes participate in NDs and tumors is necessary for developing new therapeutic tools for these increasingly common neurological conditions.
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Affiliation(s)
- Annamaria Lia
- Department Biomedical Science, University of Padova, 35131 Padova, Italy; (A.L.); (A.D.S.)
| | - Alessandro Di Spiezio
- Department Biomedical Science, University of Padova, 35131 Padova, Italy; (A.L.); (A.D.S.)
- Neuroscience Institute (CNR-IN), Padova Section, 35131 Padova, Italy
| | - Lorenzo Vitalini
- Department Life Science, University of Modena and Reggio Emilia, 41125 Modena, Italy; (L.V.); (G.P.)
| | - Manuela Tore
- Institute of Nanoscience (CNR-NANO), Modena Section, 41125 Modena, Italy;
- Department Biomedical Science, Metabolic and Neuroscience, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Giulia Puja
- Department Life Science, University of Modena and Reggio Emilia, 41125 Modena, Italy; (L.V.); (G.P.)
| | - Gabriele Losi
- Institute of Nanoscience (CNR-NANO), Modena Section, 41125 Modena, Italy;
- Department Biomedical Science, Metabolic and Neuroscience, University of Modena and Reggio Emilia, 41125 Modena, Italy
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10
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Yoshikawa M, Okubo M, Shirose K, Kan T, Kawaguchi M. d-Serine Increases Release of Acetylcholine in Rat Submandibular Glands. BIOLOGY 2023; 12:1227. [PMID: 37759626 PMCID: PMC10526048 DOI: 10.3390/biology12091227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/10/2023] [Accepted: 09/07/2023] [Indexed: 09/29/2023]
Abstract
d-serine has been observed in submandibular gland tissue in rats, but its functions remain to be clarified. Oral administration of d-serine, but not l-serine, increased its concentrations in the submandibular gland and pilocarpine-induced salivary secretion. In vivo microdialysis was used to collect the d- and l-enantiomers of amino acids from local interstitial fluid in the rat submandibular gland. The proportion of the d-form of serine in interstitial fluid was higher than that in plasma or saliva. Perfusion of the rat submandibular gland with d-serine and l-glutamic acid via the submandibular gland artery resulted in a significant increase in salivary secretion after stimulation of muscarinic receptors with carbachol. In vivo microdialysis applied to the submandibular glands of rats showed that infusion of d-serine along with l-glutamate through the microdialysis probe significantly elevated acetylcholine levels in local interstitial fluids in the submandibular glands of anesthetized rats as compared to that with l-glutamate alone in an N-methyl-d-aspartate receptor glycine site antagonist-sensitive manner. These results indicate that d-serine augments salivary secretion by increasing acetylcholine release in the salivary glands.
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Affiliation(s)
- Masanobu Yoshikawa
- Department of Clinical Pharmacology, School of Medicine, Tokai University, Isehara 259-1193, Japan
| | - Migiwa Okubo
- Kawano Dental Clinic, Yachimata 289-1101, Japan;
| | - Kosuke Shirose
- Department of Anesthesiology, School of Medicine, Tokai University, Isehara 259-1193, Japan; (K.S.); (T.K.)
| | - Takugi Kan
- Department of Anesthesiology, School of Medicine, Tokai University, Isehara 259-1193, Japan; (K.S.); (T.K.)
| | - Mitsuru Kawaguchi
- Tokyo Dental College, Misaki-cho, Chiyoda-ku, Tokyo 101-0061, Japan;
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11
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Choi JW, Seo M, Kim K, Kim AR, Lee H, Kim HS, Park CG, Cho SW, Kang JH, Joo J, Park TE. Aptamer Nanoconstructs Crossing Human Blood-Brain Barrier Discovered via Microphysiological System-Based SELEX Technology. ACS NANO 2023; 17:8153-8166. [PMID: 37068137 DOI: 10.1021/acsnano.2c11675] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Blood-brain barrier (BBB) remains one of the critical challenges in developing neurological therapeutics. Short single-stranded DNA/RNA nucleotides forming a three-dimensional structure, called aptamers, have received increasing attention as BBB shuttles for efficient brain drug delivery owing to their practical advantages over Trojan horse antibodies or peptides. Aptamers are typically obtained by combinatorial chemical technology, termed Systemic Evolution of Ligands by EXponential Enrichment (SELEX), against purified targets, living cells, or animal models. However, identifying reliable BBB-penetrating aptamers that perform efficiently under human physiological conditions has been challenging because of the poor physiological relevance in the conventional SELEX process. Here, we report a human BBB shuttle aptamer (hBS) identified using a human microphysiological system (MPS)-based SELEX (MPS-SELEX) method. A two-channel MPS lined with human brain microvascular endothelial cells (BMECs) interfaced with astrocytes and pericytes, recapitulating high-level barrier function of in vivo BBB, was exploited as a screening platform. The MPS-SELEX procedure enabled robust function-based screening of the hBS candidates, which was not achievable in traditional in vitro BBB models. The identified aptamer (hBS01) through five-round of MPS-SELEX exhibited high capability to transport protein cargoes across the human BBB via clathrin-mediated endocytosis and enhanced uptake efficiency in BMECs and brain cells. The enhanced targeting specificity of hBS01 was further validated both in vitro and in vivo, confirming its powerful brain accumulation efficiency. These findings demonstrate that MPS-SELEX has potential in the discovery of aptamers with high target specificity that can be widely utilized to boost the development of drug delivery strategies.
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Affiliation(s)
- Jeong-Won Choi
- Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea 44919
| | - Minwook Seo
- Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea 44919
| | - Kyunghwan Kim
- Department of Chemistry, College of Natural Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea 44919
| | - A-Ru Kim
- Nexmos, Inc., Yongin-si, Gyeonggi-do, Republic of Korea 16827
| | - Hakmin Lee
- Nexmos, Inc., Yongin-si, Gyeonggi-do, Republic of Korea 16827
| | - Hyung-Seok Kim
- Department of Forensic Medicine, Chonnam National University, Gwangju, Republic of Korea 61186
| | - Chun Gwon Park
- Department of Biomedical Engineering, SKKU Institute for Convergence, Sungkyunkwan University (SKKU), Suwon, Gyeonggi, Republic of Korea 16419
- Department of Intelligent Precision Healthcare Convergence, SKKU Institute for Convergence, Sungkyunkwan University (SKKU), Suwon, Gyeonggi, Republic of Korea 16419
| | - Seung Woo Cho
- Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea 44919
| | - Joo H Kang
- Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea 44919
| | - Jinmyoung Joo
- Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea 44919
| | - Tae-Eun Park
- Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea 44919
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12
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Marmouzi I, Myers S, Buck DJ, Davis RL, Arias HR. α7 Nicotinic acetylcholine receptor potentiation downregulates chemotherapy-induced inflammatory overactivation by overlapping intracellular mechanisms. Int J Biochem Cell Biol 2023; 158:106405. [PMID: 36966906 DOI: 10.1016/j.biocel.2023.106405] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 03/30/2023]
Abstract
We studied, using a combination of animal and cellular models, the glial mechanisms underlying the anti-neuropathic and anti-inflammatory properties of PAM-2 [(E)-3-furan-2-yl-N-p-tolyl-acrylamide], a positive allosteric modulator of α7 nicotinic acetylcholine receptors (nAChRs). In mice, PAM-2 decreased the inflammatory process induced by the combination of oxaliplatin (OXA), a chemotherapeutic agent, and interleukin-1β (IL-1β), a pro-inflammatory molecule. In the brain and spinal cord of treated animals, PAM-2 reduced pro-inflammatory cytokines/chemokines by mechanisms involving mRNA downregulation of factors in the toll-like receptor 4 (TLR4)/nuclear factor (NF)-κB pathway, and increased the precursor of brain-derived neurotrophic factor (proBDNF). To determine the molecular mechanisms underlying the anti-inflammatory activity of PAM-2, both human C20 microglia and normal human astrocytes (NHA) were used. The results showed that PAM-2-induced potentiation of glial α7 nAChRs decreases OXA/IL-1β-induced overexpression of inflammatory molecules by different mechanisms, including mRNA downregulation of factors in the NF-κB pathway (in microglia and astrocyte) and ERK (only in microglia). The OXA/IL-1β-mediated reduction in proBDNF was prevented by PAM-2 in microglia, but not in astrocytes. Our findings also indicate that OXA/IL-1β-induced organic cation transporter 1 (OCT1) expression is decreased by PAM-2, suggesting that decreased OXA influx may be involved in the protective effects of PAM-2. The α7-selective antagonist methyllycaconitine blocked the most important effects mediated by PAM-2 at both animal and cellular levels, supporting a mechanism involving α7 nAChRs. In conclusion, glial α7 nAChR stimulation/potentiation downregulates neuroinflammatory targets, and thereby remains a promising therapeutic option for cancer chemotherapy-induced neuroinflammation and neuropathic pain.
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Affiliation(s)
- Ilias Marmouzi
- Department of Pharmacology and Physiology, Oklahoma State University Center for Health Sciences, Tulsa, OK, USA
| | - Stephanie Myers
- Department of Pharmacology and Physiology, Oklahoma State University Center for Health Sciences, Tulsa, OK, USA
| | - Daniel J Buck
- Department of Pharmacology and Physiology, Oklahoma State University Center for Health Sciences, Tulsa, OK, USA
| | - Randall L Davis
- Department of Pharmacology and Physiology, Oklahoma State University Center for Health Sciences, Tulsa, OK, USA.
| | - Hugo R Arias
- Department of Pharmacology and Physiology, Oklahoma State University Center for Health Sciences, Tulsa, OK, USA; Department of Pharmacology and Physiology, Oklahoma State University College of Osteopathic Medicine at Cherokee Nation, Tahlequah, OK, USA
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13
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Fontana IC, Kumar A, Nordberg A. The role of astrocytic α7 nicotinic acetylcholine receptors in Alzheimer disease. Nat Rev Neurol 2023; 19:278-288. [PMID: 36977843 DOI: 10.1038/s41582-023-00792-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2023] [Indexed: 03/30/2023]
Abstract
The ongoing search for therapeutic interventions in Alzheimer disease (AD) has highlighted the complexity of this condition and the need for additional biomarkers, beyond amyloid-β (Aβ) and tau, to improve clinical assessment. Astrocytes are brain cells that control metabolic and redox homeostasis, among other functions, and are emerging as an important focus of AD research owing to their swift response to brain pathology in the initial stages of the disease. Reactive astrogliosis - the morphological, molecular and functional transformation of astrocytes during disease - has been implicated in AD progression, and the definition of new astrocytic biomarkers could help to deepen our understanding of reactive astrogliosis along the AD continuum. As we highlight in this Review, one promising biomarker candidate is the astrocytic α7 nicotinic acetylcholine receptor (α7nAChR), upregulation of which correlates with Aβ pathology in the brain of individuals with AD. We revisit the past two decades of research into astrocytic α7nAChRs to shed light on their roles in the context of AD pathology and biomarkers. We discuss the involvement of astrocytic α7nAChRs in the instigation and potentiation of early Aβ pathology and explore their potential as a target for future reactive astrocyte-based therapeutics and imaging biomarkers in AD.
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Affiliation(s)
- Igor C Fontana
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Amit Kumar
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Agneta Nordberg
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
- Theme Inflammation and Aging, Karolinska University Hospital, Stockholm, Sweden.
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14
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Lun J, Li Y, Gao X, Gong Z, Chen X, Zou J, Zhou C, Huang Y, Zhou B, Huang P, Cao H. Kynurenic acid blunts A1 astrocyte activation against neurodegeneration in HIV-associated neurocognitive disorders. J Neuroinflammation 2023; 20:87. [PMID: 36997969 PMCID: PMC10061717 DOI: 10.1186/s12974-023-02771-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 03/23/2023] [Indexed: 04/01/2023] Open
Abstract
Despite extensive astrocyte activation in patients suffering from HIV-associated neurocognitive disorders (HAND), little is known about the contribution of astrocytes to HAND neuropathology. Here, we report that the robust activation of neurotoxic astrocytes (A1 astrocytes) in the CNS promotes neuron damage and cognitive deficits in HIV-1 gp120 transgenic mice. Notably, knockout of α7 nicotinic acetylcholine receptors (α7nAChR) blunted A1 astrocyte responses, ultimately facilitating neuronal and cognitive improvement in the gp120tg mice. Furthermore, we provide evidence that Kynurenic acid (KYNA), a tryptophan metabolite with α7nAChR inhibitory properties, attenuates gp120-induced A1 astrocyte formation through the blockade of α7nAChR/JAK2/STAT3 signaling activation. Meanwhile, compared with gp120tg mice, mice fed with tryptophan showed dramatic improvement in cognitive performance, which was related to the inhibition of A1 astrocyte responses. These initial and determinant findings mark a turning point in our understanding of the role of α7nAChR in gp120-mediated A1 astrocyte activation, opening up new opportunities to control neurotoxic astrocyte generation through KYNA and tryptophan administration.
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Affiliation(s)
- Jingxian Lun
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
| | - Yubin Li
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
| | - Xuefeng Gao
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
| | - Zelong Gong
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
| | - Xiaoliang Chen
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
| | - Jinhu Zou
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
| | - Chengxing Zhou
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
| | - Yuanyuan Huang
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
| | - Bingliang Zhou
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
| | - Pengwei Huang
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
| | - Hong Cao
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515 Guangdong China
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15
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Li WP, Su XH, Hu NY, Hu J, Li XW, Yang JM, Gao TM. Astrocytes Mediate Cholinergic Regulation of Adult Hippocampal Neurogenesis and Memory Through M 1 Muscarinic Receptor. Biol Psychiatry 2022; 92:984-998. [PMID: 35787318 DOI: 10.1016/j.biopsych.2022.04.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 04/02/2022] [Accepted: 04/27/2022] [Indexed: 11/02/2022]
Abstract
BACKGROUND In the neurogenic niches of the adult hippocampus, new functional neurons are continuously generated throughout life, and generation of these neurons has been implicated in learning and memory. Astrocytes, as components of the neurogenic niches, are critical in the regulation of adult hippocampal neurogenesis (AHN). However, little is known about how astrocytes receive and respond to extrinsic cues to regulate AHN. METHODS By using a transgenic strategy to conditionally delete astrocytic CRHM1 in mice and AAV (adeno-associated virus)-mediated overexpression of astrocytic CHRM1 specifically in the hippocampal dentate gyrus, we systematically investigated the role of astrocytic CHRM1 in the regulation of AHN and the underlying mechanisms using the combined approaches of immunohistochemistry, retrovirus labeling, electrophysiology, primary astrocyte cultures, immunoblotting, and behavioral assays. RESULTS We report that genetic ablation of CHRM1 in astrocytes led to defects in neural stem cell survival, neuronal differentiation, and maturation and integration of newborn neurons in the dentate gyrus. Astrocytic CHRM1-mediated modulation of AHN was mediated by BDNF (brain-derived neurotrophic factor) signaling. Furthermore, CHRM1 ablation in astrocytes impaired contextual fear memory. These impairments in both AHN and memory were rescued by overexpression of astrocytic CHRM1 in the dentate gyrus. CONCLUSIONS Our findings reveal a critical role for astrocytes in mediating cholinergic regulation of AHN and memory through CHRM1.
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Affiliation(s)
- Wei-Peng Li
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Xiao-Hong Su
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Neng-Yuan Hu
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Jian Hu
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Xiao-Wen Li
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Jian-Ming Yang
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China.
| | - Tian-Ming Gao
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China.
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16
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McCamy KM, Rees KA, Winzer-Serhan UH. Peripheral immune challenges elicit differential up-regulation of hippocampal cytokine and chemokine mRNA expression in a mouse model of the 15q13.3 microdeletion syndrome. Cytokine 2022; 159:156005. [PMID: 36084604 DOI: 10.1016/j.cyto.2022.156005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 04/06/2022] [Accepted: 08/05/2022] [Indexed: 11/03/2022]
Abstract
The human heterozygous 15q13.3 microdeletion is associated with neuropathological disorders, most prominently with epilepsy and intellectual disability. The 1.5 Mb deletion encompasses six genes (FAN1 [MTMR15], MTMR10, TRPM1, KLF13, OTUD7A, and CHRNA7); all but one (TRPM1) are expressed in the brain. The 15q13.3 microdeletion causes highly variable neurological symptoms, and confounding factors may contribute to a more severe phenotype. CHRNA7 and KLF13 are involved in immune system regulation and altered immune responses may contribute to neurological deficits. We used the Df[h15q13]/+ transgenic mouse model with a heterozygous deletion of the orthologous region (Het) to test the hypothesis that the microdeletion increases innate immune responses compared to wild type (WT). Male and female mice were acutely challenged with the bacteriomimetic lipopolysaccharide (LPS, 0.1 mg/kg, i.p.) or the viral mimetic polyinosinic:polycytidylic acid (Poly(I:C), 5 mg/kg). Hippocampal mRNA expression of pro-inflammatory cytokines and chemokines were determined three hours after injection using quantitative PCR analysis. In controls, expression was not affected by sex or genotype. LPS and Poly(I:C) resulted in significantly increased hippocampal expression of cytokines, chemokines, and interferon-γ (IFNγ), with more robust increases for TNF-α, IL-6, IL-1β, CXCL1, and CCL2 by LPS, higher induction of IFNγ by Poly(I:C), and similar increases of CCL4 and CCL5 by both agents. Generally, Hets exhibited stronger responses than WT mice, and significant effects of genotype or genotype × treatment interactions were detected for CXCL1 and CCL5, and IL-6, IL-1β, and CCL4, respectively, after LPS. Sex differences were detected for some targets. LPS but not Poly(I:C), reduced overnight burrowing independent of sex or genotype, suggesting that LPS induced sickness behavior. Thus, mice carrying the microdeletion have an increased innate immune response following a LPS challenge, but further studies will have to determine the extent and mechanisms of altered immune activation and subsequent contributions to 15q13.3 microdeletion associated deficits.
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Affiliation(s)
- Kristin M McCamy
- Department of Neuroscience & Experimental Therapeutics, College of Medicine, Texas A&M Health Science Center, Bryan, TX 77807, United States
| | - Katherine A Rees
- Department of Neuroscience & Experimental Therapeutics, College of Medicine, Texas A&M Health Science Center, Bryan, TX 77807, United States
| | - Ursula H Winzer-Serhan
- Department of Neuroscience & Experimental Therapeutics, College of Medicine, Texas A&M Health Science Center, Bryan, TX 77807, United States.
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17
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Henn RE, Noureldein MH, Elzinga SE, Kim B, Savelieff MG, Feldman EL. Glial-neuron crosstalk in health and disease: A focus on metabolism, obesity, and cognitive impairment. Neurobiol Dis 2022; 170:105766. [PMID: 35584728 PMCID: PMC10071699 DOI: 10.1016/j.nbd.2022.105766] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/28/2022] [Accepted: 05/11/2022] [Indexed: 12/12/2022] Open
Abstract
Dementia is a complex set of disorders affecting normal cognitive function. Recently, several clinical studies have shown that diabetes, obesity, and components of the metabolic syndrome (MetS) are associated with cognitive impairment, including dementias such as Alzheimer's disease. Maintaining normal cognitive function is an intricate process involving coordination of neuron function with multiple brain glia. Well-orchestrated bioenergetics is a central requirement of neurons, which need large amounts of energy but lack significant energy storage capacity. Thus, one of the most important glial functions is to provide metabolic support and ensure an adequate energy supply for neurons. Obesity and metabolic disease dysregulate glial function, leading to a failure to respond to neuron energy demands, which results in neuronal damage. In this review, we outline evidence for links between diabetes, obesity, and MetS components to cognitive impairment. Next, we focus on the metabolic crosstalk between the three major glial cell types, oligodendrocytes, astrocytes, and microglia, with neurons under physiological conditions. Finally, we outline how diabetes, obesity, and MetS components can disrupt glial function, and how this disruption might impair glia-neuron metabolic crosstalk and ultimately promote cognitive impairment.
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Affiliation(s)
- Rosemary E Henn
- NeuroNetwork for Emerging Therapies, University of Michigan, Ann Arbor, MI, United States of America; Department of Neurology, University of Michigan, Ann Arbor, MI, United States of America.
| | - Mohamed H Noureldein
- NeuroNetwork for Emerging Therapies, University of Michigan, Ann Arbor, MI, United States of America; Department of Neurology, University of Michigan, Ann Arbor, MI, United States of America.
| | - Sarah E Elzinga
- NeuroNetwork for Emerging Therapies, University of Michigan, Ann Arbor, MI, United States of America; Department of Neurology, University of Michigan, Ann Arbor, MI, United States of America.
| | - Bhumsoo Kim
- NeuroNetwork for Emerging Therapies, University of Michigan, Ann Arbor, MI, United States of America; Department of Neurology, University of Michigan, Ann Arbor, MI, United States of America.
| | - Masha G Savelieff
- NeuroNetwork for Emerging Therapies, University of Michigan, Ann Arbor, MI, United States of America.
| | - Eva L Feldman
- NeuroNetwork for Emerging Therapies, University of Michigan, Ann Arbor, MI, United States of America; Department of Neurology, University of Michigan, Ann Arbor, MI, United States of America.
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18
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Huang Q, Liao C, Ge F, Ao J, Liu T. Acetylcholine bidirectionally regulates learning and memory. JOURNAL OF NEURORESTORATOLOGY 2022. [DOI: 10.1016/j.jnrt.2022.100002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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19
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Delijewski M, Radad K, Krewenka C, Kranner B, Moldzio R. The Reassessed Impact of Nicotine against Neurotoxicity in Mesencephalic Dopaminergic Cell Cultures and Neuroblastoma N18TG2 Cells. PLANTA MEDICA 2022; 88:548-558. [PMID: 34229355 DOI: 10.1055/a-1527-1390] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Neuroprotective effects of nicotine are still under debate, so further studies on its effectiveness against Parkinson's disease are required. In our present study, we used primary dopaminergic cell cultures and N18TG2 neuroblastoma cells to investigate the effect of nicotine and its neuroprotective potential against rotenone toxicity. Nicotine protected dopaminergic (tyrosine hydroxylase immunoreactive) neurons against rotenone. This effect was not nAChR receptor-dependent. Moreover, the alkaloid at a concentration of 5 µM caused an increase in neurite length, and at a concentration of 500 µM, it caused an increase in neurite count in dopaminergic cells exposed to rotenone. Nicotine alone was not toxic in either cell culture model, while the highest tested concentration of nicotine (500 µM) caused growth inhibition of N18TG2 neuroblastoma cells. Nicotine alone increased the level of glutathione in both cell cultures and also in rotenone-treated neuroblastoma cells. The obtained results may be helpful to explain the potential neuroprotective action of nicotine on neural cell cultures.
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Affiliation(s)
- Marcin Delijewski
- Department of Pharmacology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Katowice, Poland
| | - Khaled Radad
- Department of Pathology, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt
| | - Christopher Krewenka
- Institute of Medical Biochemistry, Department of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria
| | - Barbara Kranner
- Institute of Medical Biochemistry, Department of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria
| | - Rudolf Moldzio
- Institute of Medical Biochemistry, Department of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria
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20
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Shaykhutdinova ER, Kondrakhina AE, Ivanov IA, Kudryavtsev DS, Dyachenko IA, Murashev AN, Tsetlin VI, Utkin YN. Synthetic Analogs of 6-Bromohypaphorine, a Natural Agonist of Nicotinic Acetylcholine Receptors, Reduce Cardiac Reperfusion Injury in a Rat Model of Myocardial Ischemia. DOKL BIOCHEM BIOPHYS 2022; 503:47-51. [PMID: 35538277 DOI: 10.1134/s1607672922020132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 11/25/2021] [Accepted: 11/25/2021] [Indexed: 11/23/2022]
Abstract
The data available to date indicate that the activation of nicotinic acetylcholine receptors (nAChR) of α7 type can reduce heart damage resulting from ischemia and subsequent reperfusion. We have studied two new synthetic D-analogs of 6-bromohypaphorine, which are selective agonists of α7 nAChR, in a rat model of myocardial ischemia. Acute myocardial infarction in animals was induced by occlusion of the left coronary artery with its subsequent reperfusion under mechanical lung ventilation. It was found that one of the analogs was more active, and treatment with it at the onset of reperfusion statistically reduced infarct size. This analog also prevented changes in the concentration of potassium and sodium ions in the blood, occurring during occlusion/reperfusion injury. The data obtained indicate that hypaphorine analogs are promising for the development of drugs that reduce the adverse effects of myocardial infarction.
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Affiliation(s)
- E R Shaykhutdinova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Pushchino Branch, Russian Academy of Sciences, Pushchino, Russia
| | - A E Kondrakhina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Pushchino Branch, Russian Academy of Sciences, Pushchino, Russia
| | - I A Ivanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - D S Kudryavtsev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - I A Dyachenko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Pushchino Branch, Russian Academy of Sciences, Pushchino, Russia
| | - A N Murashev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Pushchino Branch, Russian Academy of Sciences, Pushchino, Russia
| | - V I Tsetlin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Yu N Utkin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.
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21
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Pattanaik B, Hammarlund M, Mjörnstedt F, Ulleryd MA, Zhong W, Uhlén M, Gummesson A, Bergström G, Johansson ME. Polymorphisms in alpha 7 nicotinic acetylcholine receptor gene, CHRNA7, and its partially duplicated gene, CHRFAM7A, associate with increased inflammatory response in human peripheral mononuclear cells. FASEB J 2022; 36:e22271. [PMID: 35344211 DOI: 10.1096/fj.202101898r] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 02/14/2022] [Accepted: 03/11/2022] [Indexed: 01/16/2023]
Abstract
The vagus nerve can, via the alpha 7 nicotinic acetylcholine receptor (α7nAChR), regulate inflammation. The gene coding for the α7nAChR, CHRNA7, can be partially duplicated, that is, CHRFAM7A, which is reported to impair the anti-inflammatory effect mediated via the α7nAChR. Several single nucleotide polymorphisms (SNPs) have been described in both CHRNA7 and CHRFAM7A, however, the functional role of these SNPs for immune responses remains to be investigated. In the current study, we set out to investigate whether genetic variants of CHRNA7 and CHRFAM7A can influence immune responses. By investigating data available from the Swedish SciLifeLab SCAPIS Wellness Profiling (S3WP) study, in combination with droplet digital PCR and freshly isolated PBMCs from the S3WP participants, challenged with lipopolysaccharide (LPS), we show that CHRNA7 and CHRFAM7A are expressed in human PBMCs, with approximately four times higher expression of CHRFAM7A compared with CHRNA7. One SNP in CHRFAM7A, rs34007223, is positively associated with hsCRP in healthy individuals. Furthermore, gene ontology (GO)-terms analysis of plasma proteins associated with gene expression of CHRNA7 and CHRFAM7A demonstrated an involvement for these genes in immune responses. This was further supported by in vitro data showing that several SNPs in both CHRNA7 and CHRFAM7A are significantly associated with cytokine response. In conclusion, genetic variants of CHRNA7 and CHRFAM7A alters cytokine responses. Furthermore, given that CHRFAM7A SNP rs34007223 is associated with inflammatory marker hsCRP in healthy individuals suggests that CHRFAM7A may have a more pronounced role in regulating inflammatory processes in humans than previously been recognized.
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Affiliation(s)
- Bagmi Pattanaik
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Maria Hammarlund
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Filip Mjörnstedt
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Marcus A Ulleryd
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Wen Zhong
- Science for Life Laboratory, Department of Protein Science, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Mathias Uhlén
- Science for Life Laboratory, Department of Protein Science, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Anders Gummesson
- Department of Molecular and Clinical Medicine, Wallenberg Laboratory for Cardiovascular and Metabolic Research, University of Gothenburg, Gothenburg, Sweden
| | - Göran Bergström
- Department of Molecular and Clinical Medicine, Wallenberg Laboratory for Cardiovascular and Metabolic Research, University of Gothenburg, Gothenburg, Sweden
| | - Maria E Johansson
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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22
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Manturthi S, Bhattacharya D, Sakhare KR, Narayan KP, Patri SV. Nicotinic acid-based cationic vectors for efficient gene delivery to glioblastoma cells. NEW J CHEM 2022. [DOI: 10.1039/d2nj03207d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A tocopherol-conjugated nicotinic acid-based lipid (NGT) was used for liposomal formation with the co-lipid DOPE and exhibited enhanced transfection of glioblastoma cells for eGFP and β-galactosidase protein expression.
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Affiliation(s)
- Shireesha Manturthi
- Department of Chemistry, National Institute of Technology Warangal, Hanamkonda, Telangana-506004, India
| | - Dwaipayan Bhattacharya
- Department of Biological Science, Bits pilani-hyderabad, Hyderabad, Telangana-500078, India
| | - Kalyani Rajesh Sakhare
- Department of Biological Science, Bits pilani-hyderabad, Hyderabad, Telangana-500078, India
| | - Kumar Pranav Narayan
- Department of Biological Science, Bits pilani-hyderabad, Hyderabad, Telangana-500078, India
| | - Srilakshmi V. Patri
- Department of Chemistry, National Institute of Technology Warangal, Hanamkonda, Telangana-506004, India
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23
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Ahmadpour N, Kantroo M, Stobart JL. Extracellular Calcium Influx Pathways in Astrocyte Calcium Microdomain Physiology. Biomolecules 2021; 11:1467. [PMID: 34680100 PMCID: PMC8533159 DOI: 10.3390/biom11101467] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 09/25/2021] [Accepted: 10/01/2021] [Indexed: 02/08/2023] Open
Abstract
Astrocytes are complex glial cells that play many essential roles in the brain, including the fine-tuning of synaptic activity and blood flow. These roles are linked to fluctuations in intracellular Ca2+ within astrocytes. Recent advances in imaging techniques have identified localized Ca2+ transients within the fine processes of the astrocytic structure, which we term microdomain Ca2+ events. These Ca2+ transients are very diverse and occur under different conditions, including in the presence or absence of surrounding circuit activity. This complexity suggests that different signalling mechanisms mediate microdomain events which may then encode specific astrocyte functions from the modulation of synapses up to brain circuits and behaviour. Several recent studies have shown that a subset of astrocyte microdomain Ca2+ events occur rapidly following local neuronal circuit activity. In this review, we consider the physiological relevance of microdomain astrocyte Ca2+ signalling within brain circuits and outline possible pathways of extracellular Ca2+ influx through ionotropic receptors and other Ca2+ ion channels, which may contribute to astrocyte microdomain events with potentially fast dynamics.
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Affiliation(s)
| | | | - Jillian L. Stobart
- College of Pharmacy, Rady Faculty of Health Sciences, University of Manitoba, 750 McDermot Avenue, Winnipeg, MG R3E 0T5, Canada; (N.A.); (M.K.)
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24
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Akther S, Hirase H. Assessment of astrocytes as a mediator of memory and learning in rodents. Glia 2021; 70:1484-1505. [PMID: 34582594 DOI: 10.1002/glia.24099] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 12/26/2022]
Abstract
The classical view of astrocytes is that they provide supportive functions for neurons, transporting metabolites and maintaining the homeostasis of the extracellular milieu. This view is gradually changing with the advent of molecular genetics and optical methods allowing interrogation of selected cell types in live experimental animals. An emerging view that astrocytes additionally act as a mediator of synaptic plasticity and contribute to learning processes has gained in vitro and in vivo experimental support. Here we focus on the literature published in the past two decades to review the roles of astrocytes in brain plasticity in rodents, whereby the roles of neurotransmitters and neuromodulators are considered to be comparable to those in humans. We outline established inputs and outputs of astrocytes and discuss how manipulations of astrocytes have impacted the behavior in various learning paradigms. Multiple studies suggest that the contribution of astrocytes has a considerably longer time course than neuronal activation, indicating metabolic roles of astrocytes. We advocate that exploring upstream and downstream mechanisms of astrocytic activation will further provide insight into brain plasticity and memory/learning impairment.
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Affiliation(s)
- Sonam Akther
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hajime Hirase
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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25
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Glial glucose fuels the neuronal pentose phosphate pathway for long-term memory. Cell Rep 2021; 36:109620. [PMID: 34433052 PMCID: PMC8411112 DOI: 10.1016/j.celrep.2021.109620] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 07/22/2021] [Accepted: 08/05/2021] [Indexed: 01/10/2023] Open
Abstract
Brain function relies almost solely on glucose as an energy substrate. The main model of brain metabolism proposes that glucose is taken up and converted into lactate by astrocytes to fuel the energy-demanding neuronal activity underlying plasticity and memory. Whether direct neuronal glucose uptake is required for memory formation remains elusive. We uncover, in Drosophila, a mechanism of glucose shuttling to neurons from cortex glia, an exclusively perisomatic glial subtype, upon formation of olfactory long-term memory (LTM). In vivo imaging reveals that, downstream of cholinergic activation of cortex glia, autocrine insulin signaling increases glucose concentration in glia. Glucose is then transferred from glia to the neuronal somata in the olfactory memory center to fuel the pentose phosphate pathway and allow LTM formation. In contrast, our results indicate that the increase in neuronal glucose metabolism, although crucial for LTM formation, is not routed to glycolysis. Neuronal glucose metabolism is increased upon long-term memory formation Glial cells shuttle glucose to neurons following insulin signaling activation Glucose fuels the neuronal pentose phosphate pathway
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26
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Zheng JJ, Zhang TY, Liu HT, Huang ZX, Teng JM, Deng JX, Zhong JG, Qian X, Sheng XW, Ding JQ, He SQ, Zhao X, Ji WD, Qi DF, Li W, Zhang M. Cytisine Exerts an Anti-Epileptic Effect via α7nAChRs in a Rat Model of Temporal Lobe Epilepsy. Front Pharmacol 2021; 12:706225. [PMID: 34248648 PMCID: PMC8263902 DOI: 10.3389/fphar.2021.706225] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 06/09/2021] [Indexed: 11/13/2022] Open
Abstract
Background and Purpose: Temporal lobe epilepsy (TLE) is a common chronic neurological disease that is often invulnerable to anti-epileptic drugs. Increasing data have demonstrated that acetylcholine (ACh) and cholinergic neurotransmission are involved in the pathophysiology of epilepsy. Cytisine, a full agonist of α7 nicotinic acetylcholine receptors (α7nAChRs) and a partial agonist of α4β2nAChRs, has been widely applied for smoking cessation and has shown neuroprotection in neurological diseases. However, whether cytisine plays a role in treating TLE has not yet been determined. Experimental Approach: In this study, cytisine was injected intraperitoneally into pilocarpine-induced epileptic rats for three weeks. Alpha-bungarotoxin (α-bgt), a specific α7nAChR antagonist, was used to evaluate the mechanism of action of cytisine. Rats were assayed for the occurrence of seizures and cognitive function by video surveillance and Morris water maze. Hippocampal injuries and synaptic structure were assessed by Nissl staining and Golgi staining. Furthermore, levels of glutamate, γ-aminobutyric acid (GABA), ACh, and α7nAChRs were measured. Results: Cytisine significantly reduced seizures and hippocampal damage while improving cognition and inhibiting synaptic remodeling in TLE rats. Additionally, cytisine decreased glutamate levels without altering GABA levels, and increased ACh levels and α7nAChR expression in the hippocampi of TLE rats. α-bgt antagonized the above-mentioned effects of cytisine treatment. Conclusion and Implications: Taken together, these findings indicate that cytisine exerted an anti-epileptic and neuroprotective effect in TLE rats via activation of α7nAChRs, which was associated with a decrease in glutamate levels, inhibition of synaptic remodeling, and improvement of cholinergic transmission in the hippocampus. Hence, our findings not only suggest that cytisine represents a promising anti-epileptic drug, but provides evidence of α7nAChRs as a novel therapeutic target for TLE.
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Affiliation(s)
- Jing-Jun Zheng
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China.,Department of Pharmacy, Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen, China
| | - Teng-Yue Zhang
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Hong-Tao Liu
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Ze-Xin Huang
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Jing-Mei Teng
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Jing-Xian Deng
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Jia-Gui Zhong
- Department of Neurosurgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Xu Qian
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Xin-Wen Sheng
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Ji-Qiang Ding
- Department of Neurosurgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Shu-Qiao He
- Department of Pharmacy, Maoming People's Hospital, Maoming, China
| | - Xin Zhao
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Wei-Dong Ji
- Center for Translational Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - De-Feng Qi
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hop-ital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou, China
| | - Wei Li
- Department of Neurosurgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Mei Zhang
- Key Laboratory of Molecular Target and Clinical Pharmacology, Department of Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
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27
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Aryal SP, Fu X, Sandin JN, Neupane KR, Lakes JE, Grady ME, Richards CI. Nicotine induces morphological and functional changes in astrocytes via nicotinic receptor activity. Glia 2021; 69:2037-2053. [PMID: 33851731 DOI: 10.1002/glia.24011] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 03/26/2021] [Accepted: 04/08/2021] [Indexed: 01/16/2023]
Abstract
Nicotine is a highly addictive compound present in tobacco, which causes the release of dopamine in different regions of the brain. Recent studies have shown that astrocytes express nicotinic acetylcholine receptors (nAChRs) and mediate calcium signaling. In this study, we examine the morphological and functional adaptations of astrocytes due to nicotine exposure. Utilizing a combination of fluorescence and atomic force microscopy, we show that nicotine-treated astrocytes exhibit time-dependent remodeling in the number and length of both proximal and fine processes. Blocking nAChR activity with an antagonist completely abolishes nicotine's influence on astrocyte morphology indicating that nicotine's action is mediated by these receptors. Functional studies show that 24-hr nicotine treatment induces higher levels of calcium activity in both the cell soma and the processes with a more substantial change observed in the processes. Nicotine does not induce reactive astrocytosis even at high concentrations (10 μM) as determined by cytokine release and glial fibrillary acidic protein expression. We designed tissue clearing experiments to test whether morphological changes occur in vivo using astrocyte specific Aldh1l1-tdTomato knock in mice. We find that nicotine induces a change in the volume of astrocytes in the prefrontal cortex, CA1 of the hippocampus, and the substantia nigra. These results indicate that nicotine directly alters the functional and morphological properties of astrocytes potentially contributing to the underlying mechanism of nicotine abuse.
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Affiliation(s)
- Surya P Aryal
- Department of Chemistry, University of Kentucky, Lexington, Kentucky, USA
| | - Xu Fu
- Department of Chemistry, University of Kentucky, Lexington, Kentucky, USA
| | - Joree N Sandin
- Department of Mechanical Engineering, University of Kentucky, Lexington, Kentucky, USA
| | - Khaga R Neupane
- Department of Chemistry, University of Kentucky, Lexington, Kentucky, USA
| | - Jourdan E Lakes
- Department of Chemistry, University of Kentucky, Lexington, Kentucky, USA
| | - Martha E Grady
- Department of Mechanical Engineering, University of Kentucky, Lexington, Kentucky, USA
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28
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Gaidhani N, Tucci FC, Kem WR, Beaton G, Uteshev VV. Therapeutic efficacy of α7 ligands after acute ischaemic stroke is linked to conductive states of α7 nicotinic ACh receptors. Br J Pharmacol 2021; 178:1684-1704. [PMID: 33496352 DOI: 10.1111/bph.15392] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 12/22/2020] [Accepted: 01/21/2021] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND AND PURPOSE Targeting α7 nicotinic ACh receptors (nAChRs) in neuroinflammatory disorders including acute ischaemic stroke holds significant therapeutic promise. However, therapeutically relevant signalling mechanisms remain unidentified. Activation of neuronal α7 nAChRs triggers ionotropic signalling, but there is limited evidence for it in immunoglial tissues. The α7 ligands which are effective in reducing acute ischaemic stroke damage promote α7 ionotropic activity, suggesting a link between their therapeutic effects for treating acute ischaemic stroke and activation of α7 conductive states. EXPERIMENTAL APPROACH This hypothesis was tested using a transient middle cerebral artery occlusion (MCAO) model of acute ischaemic stroke, NS6740, a known selective non-ionotropic agonist of α7 nAChRs and 4OH-GTS-21, a partial α7 agonist. NS6740-like ligands exhibiting low efficacy/potency for ionotropic activity will be referred to as non-ionotropic agonists or "metagonists". KEY RESULTS 4OH-GTS-21, used as a positive control, significantly reduced neurological deficits and brain injury after MCAO as compared to vehicle and NS6740. By contrast, NS6740 was ineffective in identical assays and reversed the effects of 4OH-GTS-21 when these compounds were co-applied. Electrophysiological recordings from acute hippocampal slices obtained from NS6740-injected animals demonstrated its remarkable brain availability and protracted effects on α7 nAChRs as evidenced by sustained (>8 h) alterations in α7 ionotropic responsiveness. CONCLUSION AND IMPLICATIONS These results suggest that α7 ionotropic activity may be obligatory for therapeutic efficacy of α7 ligands after acute ischaemic stroke yet, highlight the potential for selective application of α7 ligands to disease states based on their mode of receptor activation.
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Affiliation(s)
- Nikhil Gaidhani
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Fabio C Tucci
- Epigen Biosciences, Inc., San Diego, California, USA
| | - William R Kem
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Graham Beaton
- Epigen Biosciences, Inc., San Diego, California, USA
| | - Victor V Uteshev
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, USA
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29
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Al-Absi AR, Qvist P, Glerup S, Sanchez C, Nyengaard JR. Df(h15q13)/+ Mouse Model Reveals Loss of Astrocytes and Synaptic-Related Changes of the Excitatory and Inhibitory Circuits in the Medial Prefrontal Cortex. Cereb Cortex 2021; 31:1609-1621. [PMID: 33123721 DOI: 10.1093/cercor/bhaa313] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 08/19/2020] [Accepted: 09/20/2020] [Indexed: 11/13/2022] Open
Abstract
The 15q13.3 deletion is associated with multiple neurodevelopmental disorders including epilepsy, schizophrenia, and autism. The Df(h15q13)/+ mouse model was recently generated that recapitulates several phenotypic features of the human 15q13.3 deletion syndrome (DS). However, the biological substrates underlying these phenotypes in Df(h15q13)/+ mice have not yet been fully characterized. RNA sequencing followed by real-time quantitative PCR, western blotting, liquid chromatography-mass spectrometry, and stereological analysis were employed to dissect the molecular, structural, and neurochemical phenotypes of the medial prefrontal cortex (mPFC) circuits in Df(h15q13)/+ mouse model. Transcriptomic profiling revealed enrichment for astrocyte-specific genes among differentially expressed genes, translated by a decrease in the number of glial fibrillary acidic protein positive cells in mPFC of Df(h15q13)/+ mice compared with wild-type mice. mPFC in Df(h15q13)/+ mice also showed a deficit of the inhibitory presynaptic marker GAD65, in addition to a reduction in dendritic arborization and spine density of pyramidal neurons from layers II/III. mPFC levels of GABA and glutamate neurotransmitters were not different between genotypes. Our results suggest that the 15q13.3 deletion modulates nonneuronal circuits in mPFC and confers molecular and morphometric alterations in the inhibitory and excitatory neurocircuits, respectively. These alterations potentially contribute to the phenotypes accompanied with the 15q13.3DS.
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Affiliation(s)
- Abdel-Rahman Al-Absi
- Center for Molecular Morphology, Section for Stereology and Microscopy, Center for Stochastic Geometry and Advanced Bioimaging, Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark
| | - Per Qvist
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark.,The Lundbeck Foundation Initiative for Integrative Psychiatric Research, iPSYCH, 8210 Aarhus, Denmark.,Centre for Integrative Sequencing, iSEQ, Aarhus University, 8000 Aarhus, Denmark.,Center for Genomics and Personalized Medicine, CGPM, Aarhus University, 8000 Aarhus, Denmark
| | - Simon Glerup
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Connie Sanchez
- Translational Neuropsychiatry Unit, Aarhus University, 8000 Aarhus, Denmark
| | - Jens R Nyengaard
- Center for Molecular Morphology, Section for Stereology and Microscopy, Center for Stochastic Geometry and Advanced Bioimaging, Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark
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30
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Pucci S, Fasoli F, Moretti M, Benfante R, Di Lascio S, Viani P, Daga A, Gordon TJ, McIntosh M, Zoli M, Clementi F, Gotti C. Choline and nicotine increase glioblastoma cell proliferation by binding and activating α7- and α9- containing nicotinic receptors. Pharmacol Res 2020; 163:105336. [PMID: 33276105 DOI: 10.1016/j.phrs.2020.105336] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 11/12/2020] [Accepted: 11/25/2020] [Indexed: 12/30/2022]
Abstract
Glioblastomas (GBMs), the most frequent and aggressive human primary brain tumours, have altered cell metabolism, and one of the strongest indicators of malignancy is an increase in choline compounds. Choline is also a selective agonist of some neuronal nicotinic acetylcholine receptor (nAChR) subtypes. As little is known concerning the expression of nAChR in glioblastoma cells, we analysed in U87MG human grade-IV astrocytoma cell line and GBM5 temozolomide-resistant glioblastoma cells selected from a cancer stem cell-enriched culture, molecularly, pharmacologically and functionally which nAChR subtypes are expressed and,whether choline and nicotine can affect GBM cell proliferation. We found that U87MG and GBM5 cells express similar nAChR subtypes, and choline and nicotine increase their proliferation rate and activate the anti-apoptotic AKT and pro-proliferative ERK pathways. These effects are blocked by the presence of non-cell-permeable peptide antagonists selective for α7- and α9-containing nicotinic receptors. siRNA-mediated silencing of α7 or α9 subunit expression also selectively prevents the effects of nicotine and choline on GBM cell proliferation. Our findings indicate that nicotine and choline activate the signalling pathways involved in the proliferation of GBM cells, and that these effects are mediated by α7 and α9-containing nAChRs. This suggests that these nicotinic receptors may contribute to the aggressive behaviour of this tumor and may indicate new therapeutic strategies against high-grade human brain tumours.
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Affiliation(s)
- Susanna Pucci
- CNR, Institute of Neuroscience, Milan, Italy; NeuroMi Milan Center for Neuroscience, University of Milano-Bicocca, Italy; Hunimed University, Via Rita Levi-Montalcini 4, 20090 Pieve Emanuele (MI), Italy
| | - Francesca Fasoli
- CNR, Institute of Neuroscience, Milan, Italy; NeuroMi Milan Center for Neuroscience, University of Milano-Bicocca, Italy
| | - Milena Moretti
- CNR, Institute of Neuroscience, Milan, Italy; Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Roberta Benfante
- CNR, Institute of Neuroscience, Milan, Italy; NeuroMi Milan Center for Neuroscience, University of Milano-Bicocca, Italy; Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Simona Di Lascio
- Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Paola Viani
- Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Antonio Daga
- Cellular Oncology, IRCCS Ospedale Policlinico San Martino, Genova, Italy
| | - Thomas J Gordon
- Department of Biology, University of Utah, Salt Lake City, UT, USA
| | - Michael McIntosh
- Department of Biology, University of Utah, Salt Lake City, UT, USA; George E. Wahlen Veterans Affairs Medical Center, Salt Lake City, UT, USA; Department of Psychiatry, University of Utah, Salt Lake City, UT, USA
| | - Michele Zoli
- Department of Biomedical, Metabolic and Neural Sciences, Center for Neuroscience and Neurotechnology (CfNN), University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Francesco Clementi
- CNR, Institute of Neuroscience, Milan, Italy; Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Cecilia Gotti
- CNR, Institute of Neuroscience, Milan, Italy; NeuroMi Milan Center for Neuroscience, University of Milano-Bicocca, Italy; Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy.
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31
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Dashniani MG, Burjanadze MA, Chkhikvishvili NC, Solomonia RO, Kandashvili M, Naneishvili TL, Beselia GV, Kruashvili LB, Chighladze MR. Modulation of spatial memory and expression of hippocampal neurotransmitter receptors by selective lesion of medial septal cholinergic and GABAergic neurons. Exp Brain Res 2020; 238:2385-2397. [PMID: 32770352 DOI: 10.1007/s00221-020-05889-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 07/20/2020] [Indexed: 11/30/2022]
Abstract
The medial septum (MS) is an important modulator of hippocampal function. The degree of damage in which the particular set of septo-hippocampal projections contributes to the deficits of spatial memory with concomitant changes of hippocampal receptors expression has not been studied till present. Therefore, we investigated spatial memory and the expression level of cholinergic (α7 nACh and M1), GABAergic (α1 subunit of GABAA) and glutamatergic (NR2B subunit of NMDA and GluR 1 subunit of AMPA) receptors in the hippocampus following selective lesions of cholinergic and GABAergic septo-hippocampal projection. Learning process and long-term spatial memory were assessed using a Morris water maze. The obtained results revealed that in contrast to cholinergic lesions, rats with MS GABAergic lesions exhibit a retention deficit in 3 days after training. Western blot analyses revealed the MS cholinergic lesions have significant effect on the expression level of the M1 mACh receptors, while MS GABAergic lesions induce dramatic modulations of hippocampal glutamatergic, cholinergic and GABAergic receptors expression. These results for the first time demonstrated that selective lesions of MS cholinergic and GABAergic neurons differentially affect long-term spatial memory and the memory deficit after MS GABAergic lesion is paralleled with significant changes of hippocampal glutamate, GABA and acetylcholine receptors expression.
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Affiliation(s)
- Manana G Dashniani
- Department of Behavior and Cognitive Function, I. Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia.
| | - Maia A Burjanadze
- Department of Behavior and Cognitive Function, I. Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
| | - Nino C Chkhikvishvili
- Department of Behavior and Cognitive Function, I. Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
| | - Revaz O Solomonia
- Department of Behavior and Cognitive Function, I. Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
- Institute of Chemical Biology, Ilia State University, 0162, Tbilisi, Georgia
| | - Manana Kandashvili
- Institute of Chemical Biology, Ilia State University, 0162, Tbilisi, Georgia
| | - Temur L Naneishvili
- Department of Behavior and Cognitive Function, I. Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
| | - Gela V Beselia
- Department of Behavior and Cognitive Function, I. Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
- Department of Physiology and Pharmacology, Petre Shotadze Tbilisi Medical Academy, 0144, Tbilisi, Georgia
| | - Lali B Kruashvili
- Department of Behavior and Cognitive Function, I. Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
| | - Mariam R Chighladze
- Department of Behavior and Cognitive Function, I. Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
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32
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Felix L, Stephan J, Rose CR. Astrocytes of the early postnatal brain. Eur J Neurosci 2020; 54:5649-5672. [PMID: 32406559 DOI: 10.1111/ejn.14780] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 04/30/2020] [Accepted: 05/06/2020] [Indexed: 12/21/2022]
Abstract
In the rodent forebrain, the majority of astrocytes are generated during the early postnatal phase. Following differentiation, astrocytes undergo maturation which accompanies the development of the neuronal network. Neonate astrocytes exhibit a distinct morphology and domain size which differs to their mature counterparts. Moreover, many of the plasma membrane proteins prototypical for fully developed astrocytes are only expressed at low levels at neonatal stages. These include connexins and Kir4.1, which define the low membrane resistance and highly negative membrane potential of mature astrocytes. Newborn astrocytes moreover express only low amounts of GLT-1, a glutamate transporter critical later in development. Furthermore, they show specific differences in the properties and spatio-temporal pattern of intracellular calcium signals, resulting from differences in their repertoire of receptors and signalling pathways. Therefore, roles fulfilled by mature astrocytes, including ion and transmitter homeostasis, are underdeveloped in the young brain. Similarly, astrocytic ion signalling in response to neuronal activity, a process central to neuron-glia interaction, differs between the neonate and mature brain. This review describes the unique functional properties of astrocytes in the first weeks after birth and compares them to later stages of development. We conclude that with an immature neuronal network and wider extracellular space, astrocytic support might not be as demanding and critical compared to the mature brain. The delayed differentiation and maturation of astrocytes in the first postnatal weeks might thus reflect a reduced need for active, energy-consuming regulation of the extracellular space and a less tight control of glial feedback onto synaptic transmission.
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Affiliation(s)
- Lisa Felix
- Institute of Neurobiology, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Duesseldorf, Duesseldorf, Germany
| | - Jonathan Stephan
- Institute of Neurobiology, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Duesseldorf, Duesseldorf, Germany
| | - Christine R Rose
- Institute of Neurobiology, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Duesseldorf, Duesseldorf, Germany
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Vulfius CA, Lebedev DS, Kryukova EV, Kudryavtsev DS, Kolbaev SN, Utkin YN, Tsetlin VI. PNU-120596, a positive allosteric modulator of mammalian α7 nicotinic acetylcholine receptor, is a negative modulator of ligand-gated chloride-selective channels of the gastropod Lymnaea stagnalis. J Neurochem 2020; 155:274-284. [PMID: 32248535 DOI: 10.1111/jnc.15020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/27/2020] [Accepted: 03/24/2020] [Indexed: 12/25/2022]
Abstract
Excitatory α7 neuronal nicotinic receptors (nAChR) are widely expressed in the central and peripheral nervous and immune systems and are important for learning, memory, and immune response regulation. Specific α7 nAChR ligands, including positive allosteric modulators are promising to treat cognitive disorders, inflammatory processes, and pain. One of them, PNU-120596, highly increased the neuron response to α7 agonists and retarded desensitization, showing selectivity for α7 as compared to heteromeric nAChRs, but was not examined at the inhibitory ligand-gated channels. We studied PNU-120596 action on anion-conducting channels using voltage-clamp techniques: it slightly potentiated the response of human glycine receptors expressed in PC12 cells, of rat GABAA receptors in cerebellar Purkinje cells and mouse GABAA Rs heterologously expressed in Xenopus oocytes. On the contrary, PNU-120596 exerted an inhibitory effect on the receptors mediating anion currents in Lymnaea stagnalis neurons: two nAChR subtypes, GABA and glutamate receptors. Acceleration of the current decay, contrary to slowing down desensitization in mammalian α7 nAChR, was observed in L. stagnalis neurons predominantly expressing one of the two nAChR subtypes. Thus, PNU-120596 effect on these anion-selective nAChRs was just opposite to the action on the mammalian cation-selective α7 nAChRs. A comparison of PNU-120596 molecule docked to the models of transmembrane domains of the human α7 AChR and two subunits of L. stagnalis nAChR demonstrated some differences in contacts with the amino acid residues important for PNU-120596 action on the α7 nAChR. Thus, our results show that PNU-120596 action depends on a particular subtype of these Cys-loop receptors.
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Affiliation(s)
- Catherine A Vulfius
- Laboratory of Cellular Neurobilogy, Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino Moscow region, Russia
| | - Dmitrii S Lebedev
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Elena V Kryukova
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Denis S Kudryavtsev
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | | | - Yuri N Utkin
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Victor I Tsetlin
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
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Nicotinic Receptors Underlying Nicotine Dependence: Evidence from Transgenic Mouse Models. Curr Top Behav Neurosci 2020; 45:101-121. [PMID: 32468493 DOI: 10.1007/7854_2020_134] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Nicotine underlies the reinforcing properties of tobacco cigarettes and e-cigarettes. After inhalation and absorption, nicotine binds to various nicotinic acetylcholine receptor (nAChR) subtypes localized on the pre- and postsynaptic membranes of cells, which subsequently leads to the modulation of cellular function and neurotransmitter signaling. In this chapter, we begin by briefly reviewing the current understanding of nicotine's actions on nAChRs and highlight considerations regarding nAChR subtype localization and pharmacodynamics. Thereafter, we discuss the seminal discoveries derived from genetically modified mouse models, which have greatly contributed to our understanding of nicotine's effects on the reward-related mesolimbic pathway and the aversion-related habenulo-interpeduncular pathway. Thereafter, emerging areas of research focusing on modulation of nAChR expression and/or function are considered. Taken together, these discoveries have provided a foundational understanding of various genetic, neurobiological, and behavioral factors underlying the motivation to use nicotine and related dependence processes, which are thereby advancing drug discovery efforts to promote long-term abstinence.
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Xue R, Wan Y, Sun X, Zhang X, Gao W, Wu W. Nicotinic Mitigation of Neuroinflammation and Oxidative Stress After Chronic Sleep Deprivation. Front Immunol 2019; 10:2546. [PMID: 31736967 PMCID: PMC6828928 DOI: 10.3389/fimmu.2019.02546] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 10/14/2019] [Indexed: 12/12/2022] Open
Abstract
Sleep deprivation negatively influences all aspects of health. Oxidative stress and inflammatory responses induced by sleep deprivation participate in its adverse effects but the regulatory mechanisms to counteract them remain poorly understood. In mice subjected to sleep deprivation for 7 days, we found activation of microglia and astrocyte accompanied by down-regulation of α7 nicotinic acetylcholine receptor (α7-nAChR) and reduced activation of downstream PI3K/AKT/GSK-3β. These changes occurred with an increase of pro-inflammatory factors, together with reduced levels of anti-inflammatory factors, transcriptor Nrf-2, and anti-oxidant enzyme HO-1. Administration of an α7-nAChR agonist PHA-543613 induced activation of PI3K/AKT/GSK-3β, and reversed changes in pro-inflammatory and anti-inflammatory factors, Nrf-2 and HO-1. These results suggest that stimulation of α7-nAChR reduce neuroinflammation and oxidative stress after chronic sleep deprivation.
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Affiliation(s)
- Rong Xue
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China
| | - Yahui Wan
- Department of Neurology, Tianjin Medical University General Hospital Airport Hospital, Tianjin, China
| | - Xiaoqian Sun
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China
| | - Xuan Zhang
- Department of Neurology, Tianjin Medical University General Hospital Airport Hospital, Tianjin, China
| | - Wei Gao
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China
| | - Wei Wu
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China
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Kynurenines and the Endocannabinoid System in Schizophrenia: Common Points and Potential Interactions. Molecules 2019; 24:molecules24203709. [PMID: 31619006 PMCID: PMC6832375 DOI: 10.3390/molecules24203709] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/09/2019] [Accepted: 10/14/2019] [Indexed: 12/15/2022] Open
Abstract
Schizophrenia, which affects around 1% of the world’s population, has been described as a complex set of symptoms triggered by multiple factors. However, the exact background mechanisms remain to be explored, whereas therapeutic agents with excellent effectivity and safety profiles have yet to be developed. Kynurenines and the endocannabinoid system (ECS) play significant roles in both the development and manifestation of schizophrenia, which have been extensively studied and reviewed previously. Accordingly, kynurenines and the ECS share multiple features and mechanisms in schizophrenia, which have yet to be reviewed. Thus, the present study focuses on the main common points and potential interactions between kynurenines and the ECS in schizophrenia, which include (i) the regulation of glutamatergic/dopaminergic/γ-aminobutyric acidergic neurotransmission, (ii) their presence in astrocytes, and (iii) their role in inflammatory mechanisms. Additionally, promising pharmaceutical approaches involving the kynurenine pathway and the ECS will be reviewed herein.
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Nielsen BE, Bermudez I, Bouzat C. Flavonoids as positive allosteric modulators of α7 nicotinic receptors. Neuropharmacology 2019; 160:107794. [PMID: 31560909 DOI: 10.1016/j.neuropharm.2019.107794] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 08/09/2019] [Accepted: 09/23/2019] [Indexed: 12/11/2022]
Abstract
The use of positive allosteric modulators (PAM) of α7 nicotinic receptors is a promising therapy for neurodegenerative, inflammatory and cognitive disorders. Flavonoids are polyphenolic compounds showing neuroprotective, anti-inflammatory and pro-cognitive actions. Besides their well-known antioxidant activity, flavonoids trigger intracellular pathways and interact with receptors, including α7. To reveal how the beneficial actions of flavonoids are linked to α7 function, we evaluated the effects of three representative flavonoids -genistein, quercetin and the neoflavonoid 5,7-dihydroxy-4-phenylcoumarin- on whole-cell and single-channel currents. All flavonoids increase the maximal currents elicited by acetylcholine with minimal effects on desensitization and do not reactivate desensitized receptors, a behaviour consistent with type I PAMs. At the single-channel level, they increase the duration of the open state and produce activation in long-duration episodes with a rank order of efficacy of genistein > quercetin ≥ neoflavonoid. By using mutant and chimeric α7 receptors, we demonstrated that flavonoids share transmembrane structural determinants with other PAMs. The α7-PAM activity of flavonoids results in decreased cell levels of reactive oxygen species. Thus, allosteric potentiation of α7 may be an additional mechanism underlying neuroprotective actions of flavonoids, which may be used as scaffolds for designing new therapeutic agents.
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Affiliation(s)
- Beatriz Elizabeth Nielsen
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bahía Blanca 8000, Argentina
| | - Isabel Bermudez
- Department of Medical and Biological Sciences, Oxford Brookes University, Oxford, OX3 0BP, United Kingdom
| | - Cecilia Bouzat
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bahía Blanca 8000, Argentina.
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α7 nicotinic acetylcholine receptor upregulation by anti-apoptotic Bcl-2 proteins. Nat Commun 2019; 10:2746. [PMID: 31227712 PMCID: PMC6588605 DOI: 10.1038/s41467-019-10723-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 05/24/2019] [Indexed: 01/07/2023] Open
Abstract
Nicotinic acetylcholine receptors (nAChRs) mediate and modulate synaptic transmission throughout the brain, and contribute to learning, memory, and behavior. Dysregulation of α7-type nAChRs in neuropsychiatric as well as immunological and oncological diseases makes them attractive targets for pharmaceutical development. Recently, we identified NACHO as an essential chaperone for α7 nAChRs. Leveraging the robust recombinant expression of α7 nAChRs with NACHO, we utilized genome-wide cDNA library screening and discovered that several anti-apoptotic Bcl-2 family proteins further upregulate receptor assembly and cell surface expression. These effects are mediated by an intracellular motif on α7 that resembles the BH3 binding domain of pro-apoptotic Bcl-2 proteins, and can be blocked by BH3 mimetic Bcl-2 inhibitors. Overexpression of Bcl-2 member Mcl-1 in neurons enhanced surface expression of endogenous α7 nAChRs, while a combination of chemotherapeutic Bcl2-inhibitors suppressed neuronal α7 receptor assembly. These results demonstrate that Bcl-2 proteins link α7 nAChR assembly to cell survival pathways. The α7 nicotinic acetylcholine receptor (nAChR) plays a major role in shaping the activity of neuronal circuits and contributes to the pathophysiology of several neurological disorders. Following cDNA library screening, the authors identify anti-apoptotic, Bcl-2 family proteins as enhancers of α7 nAChR assembly, acting through an intracellular BH3-like domain during receptor biogenesis in the endoplasmic reticulum.
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Lottig L, Bader S, Jimenez M, Diener M. Evidence for metabotropic function of epithelial nicotinic cholinergic receptors in rat colon. Br J Pharmacol 2019; 176:1328-1340. [PMID: 30807644 DOI: 10.1111/bph.14638] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 01/08/2019] [Accepted: 02/03/2019] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND AND PURPOSE ACh exerts its actions via nicotinic (nAChR) and muscarinic receptors. In the peripheral nervous system, ionotropic nAChR mediate responses in excitable cells. However, recent studies demonstrate the expression of nAChR in the colonic epithelium, which are coupled to an induction of Cl- secretion via activation of the Na+ -K+ -pump. EXPERIMENTAL APPROACH In order to find out whether these epithelial nAChR function as ionotropic receptors, intracellular microelectrode and imaging experiments were performed in isolated crypts from rat colon. Apically permeabilized epithelia were used to measure pump current across the basolateral membrane. KEY RESULTS Imaging experiments with the Na+ -sensitive dye SBFI revealed that nicotine induced a decrease in the cytosolic Na+ concentration concomitant with a fall in the cytosolic Ca2+ concentration in about 50% of the cells. as shown in fura-2 experiments. Nicotine hyperpolarized the membrane by 6.4 ± 2.1 mV. These observations contradict the assumption that epithelial nAChR function as ligand-gated non-selective cation channels. The decrease in the cytosolic Na+ concentration was strongly delayed, when the Na+ -K+ -pump was inhibited by scilliroside. Ussing chamber experiments revealed a strong dependence of the nicotine-induced pump current on the presence of Ca2+ , and chelation of cytosolic Ca2+ with BAPTA prevented the fall in the cytosolic Na+ concentration in SBFI-loaded crypts. Inhibition of PKC with GF 109203X or Goe 6983 significantly reduced the nicotine-induced pump current. CONCLUSIONS AND IMPLICATIONS These results suggest that epithelial nAChR activate the Na+ -K+ -pump via a PKC dependent on a sufficient cytosolic Ca2+ concentration.
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Affiliation(s)
- Lena Lottig
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-University Giessen, Giessen, Germany
| | - Sandra Bader
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-University Giessen, Giessen, Germany
| | - Marcel Jimenez
- Department of Cell Biology, Physiology and Immunology, Veterinary Faculty, Universitat Autonoma de Barcelona, Barcelona, Spain
| | - Martin Diener
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-University Giessen, Giessen, Germany
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Hassan M, Shahzadi S, Raza H, Abbasi MA, Alashwal H, Zaki N, Moustafa AA, Seo SY. Computational investigation of mechanistic insights of Aβ42 interactions against extracellular domain of nAChRα7 in Alzheimer's disease. Int J Neurosci 2019; 129:666-680. [PMID: 30422726 DOI: 10.1080/00207454.2018.1543670] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
AIM Amyloid beta (Aβ) 1-42, which is a basic constituent of amyloid plaques, binds with extracellular transmembrane receptor nicotine acetylcholine receptor α7 (nAChRα7) in Alzheimer's disease. MATERIALS AND METHODS In the current study, a computational approach was employed to explore the active binding sites of nAChRα7 through Aβ 1-42 interactions and their involvement in the activation of downstream signalling pathways. Sequential and structural analyses were performed on the extracellular part of nAChRα7 to identify its core active binding site. RESULTS Results showed that a conserved residual pattern and well superimposed structures were observed in all nAChRs proteins. Molecular docking servers were used to predict the common interactive residues in nAChRα7 and Aβ1-42 proteins. The docking profile results showed some common interactive residues such as Glu22, Ala42 and Trp171 may consider as the active key player in the activation of downstream signalling pathways. Moreover, the signal communication and receiving efficacy of best-docked complexes was checked through DynOmic online server. Furthermore, the results from molecular dynamic simulation experiment showed the stability of nAChRα7. The generated root mean square deviations and fluctuations (RMSD/F), solvent accessible surface area (SASA) and radius of gyration (Rg) graphs of nAChRα7 also showed its backbone stability and compactness, respectively. CONCLUSION Taken together, our predicted results intimated the structural insight on the molecular interactions of beta amyloid protein involved in the activation of nAChRα7 receptor. In future, a better understanding of nAChRα7 and their interconnected proteins signalling cascade may be consider as target to cure Alzheimer's disease.
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Affiliation(s)
- Mubashir Hassan
- a Department of Biological Sciences, College of Natural Sciences , Kongju National University , Gongju , Chungnam-do 32588 , Republic of Korea
| | - Saba Shahzadi
- b Institute of Molecular Science and Bioinformatics , Lahore , Pakistan.,c Department of Bioinformatics , Virtual University of Pakistan , Lahore , Pakistan
| | - Hussain Raza
- a Department of Biological Sciences, College of Natural Sciences , Kongju National University , Gongju , Chungnam-do 32588 , Republic of Korea
| | - Muhammad Athar Abbasi
- a Department of Biological Sciences, College of Natural Sciences , Kongju National University , Gongju , Chungnam-do 32588 , Republic of Korea.,d Department of Chemistry , Government College University , Lahore , Pakistan
| | - Hany Alashwal
- e Department of Computer Science and Software Engineering, College of Information Technology , United Arab Emirates University , Al-Ain , United Arab Emirates
| | - Nazar Zaki
- e Department of Computer Science and Software Engineering, College of Information Technology , United Arab Emirates University , Al-Ain , United Arab Emirates
| | - Ahmed A Moustafa
- f School of Social Sciences and Psychology.,g MARCS Institute for Brain and Behaviour , Western Sydney University , Sydney , New South Wales , Australia.,h Department of Social Sciences, College of Arts and Sciences , Qatar University , Doha , Qatar'
| | - Sung-Yum Seo
- a Department of Biological Sciences, College of Natural Sciences , Kongju National University , Gongju , Chungnam-do 32588 , Republic of Korea
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Otto SL, Yakel JL. The α7 nicotinic acetylcholine receptors regulate hippocampal adult-neurogenesis in a sexually dimorphic fashion. Brain Struct Funct 2018; 224:829-846. [PMID: 30515567 DOI: 10.1007/s00429-018-1799-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 11/16/2018] [Indexed: 12/17/2022]
Abstract
Disruption in cholinergic signaling has been linked to many environmental and/or pathological conditions known to modify adult neurogenesis. The α7 nAChRs are in the family of cys-loop receptor channels which have been shown to be neuroprotective in adult neurons and are thought to be critical for survival and integration of immature neurons. However, in developing neurons, poor calcium buffering may cause α7 nAChR activation to be neurotoxic. To investigate whether the α7 nAChR regulates neurogenesis in the hippocampus, we used a combination of mouse genetics and imaging to quantify neural stem cell (NSC) densities located in the dentate gyrus of adult mice. In addition, we considered whether the loss of α7 nAChRs had functional consequences on a spatial discrimination task that is thought to rely on pattern separation mechanisms. We found that the loss of α7 nAChRs resulted in increased neurogenesis in male mice only, while female mice showed increased cell divisions and intermediate progenitors but no change in neurogenesis. Knocking out the α7 nAChR from nestin+ NSCs and their progeny showed signaling in these cells contributes to regulating neurogenesis. In addition, male, but not female, mice lacking α7 nAChRs performed significantly worse in the spatial discrimination task. This task was sexually dimorphic in wild-type mice, but not in the absence of α7 nAChRs. We conclude that α7 nAChRs regulate adult neurogenesis and impact spatial discrimination function in male, but not female mice, via a mechanism involving nestin+ NSCs and their progeny.
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Affiliation(s)
- Simone L Otto
- Neurobiology Laboratory, 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
| | - Jerrel L Yakel
- Neurobiology Laboratory, 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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Linker KE, Cross SJ, Leslie FM. Glial mechanisms underlying substance use disorders. Eur J Neurosci 2018; 50:2574-2589. [PMID: 30240518 DOI: 10.1111/ejn.14163] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 08/23/2018] [Accepted: 08/28/2018] [Indexed: 12/28/2022]
Abstract
Addiction is a devastating disorder that produces persistent maladaptive changes to the central nervous system, including glial cells. Although there is an extensive body of literature examining the neuronal mechanisms of substance use disorders, effective therapies remain elusive. Glia, particularly microglia and astrocytes, have an emerging and meaningful role in a variety of processes beyond inflammation and immune surveillance, and may represent a promising therapeutic target. Indeed, glia actively modulate neurotransmission, synaptic connectivity and neural circuit function, and are critically poised to contribute to addictive-like brain states and behaviors. In this review, we argue that glia influence the cellular, molecular, and synaptic changes that occur in neurons following drug exposure, and that this cellular relationship is critically modified following drug exposure. We discuss direct actions of abused drugs on glial function through immune receptors, such as Toll-like receptor 4, as well as other mechanisms. We highlight how drugs of abuse affect glia-neural communication, and the profound effects that glial-derived factors have on neuronal excitability, structure, and function. Recent research demonstrates that glia have brain region-specific functions, and glia in different brain regions have distinct contributions to drug-associated behaviors. We will also evaluate the evidence demonstrating that glial activation is essential for drug reward and drug-induced dopamine release, and highlight clinical evidence showing that glial mechanisms contribute to drug abuse liability. In this review, we synthesize the extensive evidence that glia have a unique, pivotal, and underappreciated role in the development and maintenance of addiction.
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Affiliation(s)
- K E Linker
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - S J Cross
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - F M Leslie
- Department of Pharmacology, University of California Irvine, Irvine, CA, USA
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Dark C, Homman-Ludiye J, Bryson-Richardson RJ. The role of ADHD associated genes in neurodevelopment. Dev Biol 2018; 438:69-83. [DOI: 10.1016/j.ydbio.2018.03.023] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 03/04/2018] [Accepted: 03/27/2018] [Indexed: 12/19/2022]
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Calarco CA, Li Z, Taylor SR, Lee S, Zhou W, Friedman JM, Mineur YS, Gotti C, Picciotto MR. Molecular and cellular characterization of nicotinic acetylcholine receptor subtypes in the arcuate nucleus of the mouse hypothalamus. Eur J Neurosci 2018; 48:10.1111/ejn.13966. [PMID: 29791746 PMCID: PMC6251769 DOI: 10.1111/ejn.13966] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 04/26/2018] [Accepted: 05/09/2018] [Indexed: 12/22/2022]
Abstract
Nicotine, acting through nicotinic acetylcholine receptors (nAChRs), increases the firing rate of both orexigenic agouti-related peptide (AgRP) and anorexigenic pro-opiomelanocortin (POMC) neurons in the arcuate nucleus of the hypothalamus (ARC), yet nicotine and other nAChR agonists decrease food intake in mice. Viral-mediated knockdown of the β4 nAChR subunit in all neuronal cell types in the ARC prevents the nicotinic agonist cytisine from decreasing food intake, but it is not known whether the β4 subunit is selectively expressed in anorexigenic neurons or how other nAChR subtypes are distributed in this nucleus. Using translating ribosome affinity purification (TRAP) on ARC tissue from mice with ribosomes tagged in either AgRP or POMC cells, we examined nAChR subunit mRNA levels using real-time PCR. Both AgRP and POMC cells express a comparable panel of nAChR subunits with differences in α7 mRNA levels and a trend for difference in α4 levels, but no differences in β4 expression. Immunoprecipitation of assembled nAChRs revealed that the β4 subunit forms assembled channels with α3, β2 and α4, but not other subunits found in the ARC. Finally, using cell type-selective, virally delivered small hairpin RNAs targeting either the β4 or α7 subunit, we examined the contribution of each subunit in either AgRP or POMC cells to the behavioural response to nicotine, refining the understanding of nicotinic regulation of this feeding circuit. These experiments identify a more complex set of nAChRs expressed in ARC than in other hypothalamic regions. Thus, the ARC appears to be a particular target of nicotinic modulation.
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Affiliation(s)
- Cali A. Calarco
- Department of Psychiatry and Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06508, USA
| | | | - Seth R. Taylor
- Department of Psychiatry and Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06508, USA
| | - Somin Lee
- Department of Psychiatry and Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06508, USA
| | - Wenliang Zhou
- Department of Psychiatry and Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06508, USA
| | | | - Yann S. Mineur
- Department of Psychiatry and Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06508, USA
| | | | - Marina R. Picciotto
- Department of Psychiatry and Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06508, USA
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Pacheco SM, Azambuja JH, de Carvalho TR, Soares MSP, Oliveira PS, da Silveira EF, Stefanello FM, Braganhol E, Gutierres JM, Spanevello RM. Glioprotective Effects of Lingonberry Extract Against Altered Cellular Viability, Acetylcholinesterase Activity, and Oxidative Stress in Lipopolysaccharide-Treated Astrocytes. Cell Mol Neurobiol 2018; 38:1107-1121. [PMID: 29556871 DOI: 10.1007/s10571-018-0581-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 03/05/2018] [Indexed: 01/24/2023]
Abstract
Altered astrocytic function is a contributing factor to the development of neurological diseases and neurodegeneration. Berry fruits exert neuroprotective effects by modulating pathways involved in inflammation, neurotransmission, and oxidative stress. The aim of this study was to examine the effects of the lingonberry extract on cellular viability and oxidative stress in astrocytes exposed to lipopolysaccharide (LPS). In the reversal protocol, primary astrocytic cultures were first exposed to 1 µg/mL LPS for 3 h and subsequently treated with lingonberry extract (10, 30, 50, and 100 μg/mL) for 24 and 48 h. In the prevention protocol, exposure to the lingonberry extract was performed before treatment with LPS. In both reversal and prevention protocols, the lingonberry extracts, from 10 to 100 μg/mL, attenuated LPS-induced increase in reactive oxygen species (around 55 and 45%, respectively, P < 0.01), nitrite levels (around 50 and 45%, respectively, P < 0.05), and acetylcholinesterase activity (around 45 and 60%, respectively, P < 0.05) in astrocytic cultures at 24 and 48 h. Also, in both reversal and prevention protocols, the lingonberry extract also prevented and reversed the LPS-induced decreased cellular viability (around 45 and 90%, respectively, P < 0.05), thiol content (around 55 and 70%, respectively, P < 0.05), and superoxide dismutase activity (around 50 and 145%, respectively, P < 0.05), in astrocytes at both 24 and 48 h. Our findings suggested that the lingonberry extract exerted a glioprotective effect through an anti-oxidative mechanism against LPS-induced astrocytic damage.
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Affiliation(s)
- Simone Muniz Pacheco
- Programa de Pós-Graduação em Bioquímica e Bioprospecção, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Caixa Postal 354, Campus Capão do Leão, s/n, Pelotas, 96010-900, RS, Brazil
| | - Juliana Hofstätter Azambuja
- Programa de Pós-Graduação em Biociências, Departamento de Ciências Básicas da Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, 90050-170, RS, Brazil
| | - Taíse Rosa de Carvalho
- Programa de Pós-Graduação em Bioquímica e Bioprospecção, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Caixa Postal 354, Campus Capão do Leão, s/n, Pelotas, 96010-900, RS, Brazil
| | - Mayara Sandrielly Pereira Soares
- Programa de Pós-Graduação em Bioquímica e Bioprospecção, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Caixa Postal 354, Campus Capão do Leão, s/n, Pelotas, 96010-900, RS, Brazil
| | - Pathise Souto Oliveira
- Programa de Pós-Graduação em Bioquímica e Bioprospecção, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Caixa Postal 354, Campus Capão do Leão, s/n, Pelotas, 96010-900, RS, Brazil
| | - Elita Ferreira da Silveira
- Programa de Pós-Graduação em Ciências Fisiológicas, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, CEP 96201-900, RS, Brazil
| | - Francieli Moro Stefanello
- Programa de Pós-Graduação em Bioquímica e Bioprospecção, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Caixa Postal 354, Campus Capão do Leão, s/n, Pelotas, 96010-900, RS, Brazil
| | - Elizandra Braganhol
- Programa de Pós-Graduação em Biociências, Departamento de Ciências Básicas da Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, 90050-170, RS, Brazil
| | - Jessié Martins Gutierres
- Programa de Pós-Graduação em Bioquímica e Bioprospecção, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Caixa Postal 354, Campus Capão do Leão, s/n, Pelotas, 96010-900, RS, Brazil
| | - Roselia Maria Spanevello
- Programa de Pós-Graduação em Bioquímica e Bioprospecção, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Caixa Postal 354, Campus Capão do Leão, s/n, Pelotas, 96010-900, RS, Brazil.
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Mei YY, Wu DC, Zhou N. Astrocytic Regulation of Glutamate Transmission in Schizophrenia. Front Psychiatry 2018; 9:544. [PMID: 30459650 PMCID: PMC6232167 DOI: 10.3389/fpsyt.2018.00544] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 10/12/2018] [Indexed: 01/19/2023] Open
Abstract
According to the glutamate hypothesis of schizophrenia, the abnormality of glutamate transmission induced by hypofunction of NMDA receptors (NMDARs) is causally associated with the positive and negative symptoms of schizophrenia. However, the underlying mechanisms responsible for the changes in glutamate transmission in schizophrenia are not fully understood. Astrocytes, the major regulatory glia in the brain, modulate not only glutamate metabolism but also glutamate transmission. Here we review the recent progress in understanding the role of astrocytes in schizophrenia. We focus on the astrocytic mechanisms of (i) glutamate synthesis via the glutamate-glutamine cycle, (ii) glutamate clearance by excitatory amino acid transporters (EAATs), (iii) D-serine release to activate NMDARs, and (iv) glutamatergic target engagement biomarkers. Abnormality in these processes is highly correlated with schizophrenia phenotypes. These findings will shed light upon further investigation of pathogenesis as well as improvement of biomarkers and therapies for schizophrenia.
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Affiliation(s)
- Yu-Ying Mei
- Translational Medicine Research Center, China Medical University Hospital, Taichung, Taiwan.,Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan
| | - Dong Chuan Wu
- Translational Medicine Research Center, China Medical University Hospital, Taichung, Taiwan.,Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan
| | - Ning Zhou
- Translational Medicine Research Center, China Medical University Hospital, Taichung, Taiwan.,Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan
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Happ DF, Tasker RA. Effects of α7 Nicotinic Receptor Activation on Cell Survival in Rat Organotypic Hippocampal Slice Cultures. Neurotox Res 2017; 33:887-895. [DOI: 10.1007/s12640-017-9854-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 12/04/2017] [Accepted: 12/13/2017] [Indexed: 11/28/2022]
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Dannenberg H, Young K, Hasselmo M. Modulation of Hippocampal Circuits by Muscarinic and Nicotinic Receptors. Front Neural Circuits 2017; 11:102. [PMID: 29321728 PMCID: PMC5733553 DOI: 10.3389/fncir.2017.00102] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Accepted: 11/27/2017] [Indexed: 01/02/2023] Open
Abstract
This article provides a review of the effects of activation of muscarinic and nicotinic receptors on the physiological properties of circuits in the hippocampal formation. Previous articles have described detailed computational hypotheses about the role of cholinergic neuromodulation in enhancing the dynamics for encoding in cortical structures and the role of reduced cholinergic modulation in allowing consolidation of previously encoded information. This article will focus on addressing the broad scope of different modulatory effects observed within hippocampal circuits, highlighting the heterogeneity of cholinergic modulation in terms of the physiological effects of activation of muscarinic and nicotinic receptors and the heterogeneity of effects on different subclasses of neurons.
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Affiliation(s)
- Holger Dannenberg
- Center for Systems Neuroscience, Department of Psychological and Brain Sciences, Boston University, Boston, MA, United States
| | - Kimberly Young
- Center for Systems Neuroscience, Department of Psychological and Brain Sciences, Boston University, Boston, MA, United States
| | - Michael Hasselmo
- Center for Systems Neuroscience, Department of Psychological and Brain Sciences, Boston University, Boston, MA, United States
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49
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Maurer SV, Williams CL. The Cholinergic System Modulates Memory and Hippocampal Plasticity via Its Interactions with Non-Neuronal Cells. Front Immunol 2017; 8:1489. [PMID: 29167670 PMCID: PMC5682336 DOI: 10.3389/fimmu.2017.01489] [Citation(s) in RCA: 149] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/23/2017] [Indexed: 01/12/2023] Open
Abstract
Degeneration of central cholinergic neurons impairs memory, and enhancement of cholinergic synapses improves cognitive processes. Cholinergic signaling is also anti-inflammatory, and neuroinflammation is increasingly linked to adverse memory, especially in Alzheimer's disease. Much of the evidence surrounding cholinergic impacts on the neuroimmune system focuses on the α7 nicotinic acetylcholine (ACh) receptor, as stimulation of this receptor prevents many of the effects of immune activation. Microglia and astrocytes both express this receptor, so it is possible that some cholinergic effects may be via these non-neuronal cells. Though the presence of microglia is required for memory, overactivated microglia due to an immune challenge overproduce inflammatory cytokines, which is adverse for memory. Blocking these exaggerated effects, specifically by decreasing the release of tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and interleukin 6 (IL-6), has been shown to prevent inflammation-induced memory impairment. While there is considerable evidence that cholinergic signaling improves memory, fewer studies have linked the "cholinergic anti-inflammatory pathway" to memory processes. This review will summarize the current understanding of the cholinergic anti-inflammatory pathway as it relates to memory and will argue that one mechanism by which the cholinergic system modulates hippocampal memory processes is its influence on neuroimmune function via the α7 nicotinic ACh receptor.
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Affiliation(s)
- Sara V. Maurer
- Department of Psychology and Neuroscience, Duke University, Durham, NC, United States
| | - Christina L. Williams
- Department of Psychology and Neuroscience, Duke University, Durham, NC, United States
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The current agonists and positive allosteric modulators of α7 nAChR for CNS indications in clinical trials. Acta Pharm Sin B 2017; 7:611-622. [PMID: 29159020 PMCID: PMC5687317 DOI: 10.1016/j.apsb.2017.09.001] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 08/02/2017] [Accepted: 08/25/2017] [Indexed: 01/06/2023] Open
Abstract
The alpha-7 nicotinic acetylcholine receptor (α7 nAChR), consisting of homomeric α7 subunits, is a ligand-gated Ca2+-permeable ion channel implicated in cognition and neuropsychiatric disorders. Enhancement of α7 nAChR function is considered to be a potential therapeutic strategy aiming at ameliorating cognitive deficits of neuropsychiatric disorders such as Alzheimer's disease (AD) and schizophrenia. Currently, a number of α7 nAChR modulators have been reported and several of them have advanced into clinical trials. In this brief review, we outline recent progress made in understanding the role of the α7 nAChR in multiple neuropsychiatric disorders and the pharmacological effects of α7 nAChR modulators used in clinical trials.
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Key Words
- 5-CSRTT, five-choice serial reaction time task
- 5-HT, serotonin
- ACh, acetylcholine
- AD, Alzheimer's disease
- ADHD, attention deficit hyperactivity disorder
- Acetylcholine
- Alpha7
- Alzheimer's disease
- Aβ, amyloid-β peptide
- CNS, central nervous system
- DMTS, delayed matching-to-sample
- ECD, extracellular domain
- GABA, γ-aminobutyric acid
- Ion channel
- MLA, methyllycaconitine
- NOR, novel object recognition
- PAMs, positive allosteric modulators
- PCP, neonatal phencyclidine
- PD, Parkinson's disease
- PPI, prepulse inhibition
- Positive allosteric modulators
- SAR, structure–activity relationship
- Schizophrenia
- TMD, transmembrane domains
- nAChR
- nAChR, nicotinic acetylcholine receptor
- α-Btx, α-bungarotoxin
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