1
|
Richter K, Asci N, Singh VK, Yakoob SH, Meixner M, Zakrzewicz A, Liese J, Hecker A, Wilker S, Stumpf S, Schlüter KD, Rohde M, Gödecke A, Padberg W, Manzini I, Schmalzing G, Grau V. Activation of endothelial NO synthase and P2X7 receptor modification mediates the cholinergic control of ATP-induced interleukin-1β release by mononuclear phagocytes. Front Immunol 2023; 14:1140592. [PMID: 36969210 PMCID: PMC10034071 DOI: 10.3389/fimmu.2023.1140592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 02/27/2023] [Indexed: 03/12/2023] Open
Abstract
ObjectiveThe pro-inflammatory cytokine interleukin-1β (IL-1β) plays a central role in host defense against infections. High systemic IL-1β levels, however, promote the pathogenesis of inflammatory disorders. Therefore, mechanisms controlling IL-1β release are of substantial clinical interest. Recently, we identified a cholinergic mechanism inhibiting the ATP-mediated IL-1β release by human monocytes via nicotinic acetylcholine receptor (nAChR) subunits α7, α9 and/or α10. We also discovered novel nAChR agonists that trigger this inhibitory function in monocytic cells without eliciting ionotropic functions at conventional nAChRs. Here, we investigate the ion flux-independent signaling pathway that links nAChR activation to the inhibition of the ATP-sensitive P2X7 receptor (P2X7R).MethodsDifferent human and murine mononuclear phagocytes were primed with lipopolysaccharide and stimulated with the P2X7R agonist BzATP in the presence or absence of nAChR agonists, endothelial NO synthase (eNOS) inhibitors, and NO donors. IL-1β was measured in cell culture supernatants. Patch-clamp and intracellular Ca2+ imaging experiments were performed on HEK cells overexpressing human P2X7R or P2X7R with point mutations at cysteine residues in the cytoplasmic C-terminal domain.ResultsThe inhibitory effect of nAChR agonists on the BzATP-induced IL-1β release was reversed in the presence of eNOS inhibitors (L-NIO, L-NAME) as well as in U937 cells after silencing of eNOS expression. In peripheral blood mononuclear leukocytes from eNOS gene-deficient mice, the inhibitory effect of nAChR agonists was absent, suggesting that nAChRs signal via eNOS to inhibit the BzATP-induced IL-1β release. Moreover, NO donors (SNAP, S-nitroso-N-acetyl-DL-penicillamine; SIN-1) inhibited the BzATP-induced IL-1β release by mononuclear phagocytes. The BzATP-induced ionotropic activity of the P2X7R was abolished in the presence of SIN-1 in both, Xenopus laevis oocytes and HEK cells over-expressing the human P2X7R. This inhibitory effect of SIN-1 was absent in HEK cells expressing P2X7R, in which C377 was mutated to alanine, indicating the importance of C377 for the regulation of the P2X7R function by protein modification.ConclusionWe provide first evidence that ion flux-independent, metabotropic signaling of monocytic nAChRs involves eNOS activation and P2X7R modification, resulting in an inhibition of ATP signaling and ATP-mediated IL-1β release. This signaling pathway might be an interesting target for the treatment of inflammatory disorders.
Collapse
Affiliation(s)
- Katrin Richter
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University Giessen, German Centre for Lung Research (DZL), Cardio Pulmonary Institute (CPI), Giessen, Germany
- *Correspondence: Katrin Richter,
| | - Nilay Asci
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University Giessen, German Centre for Lung Research (DZL), Cardio Pulmonary Institute (CPI), Giessen, Germany
| | - Vijay K. Singh
- Department of Paediatric Haematology and Oncology, Justus-Liebig-University, Giessen, Germany
| | | | - Marion Meixner
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University Giessen, German Centre for Lung Research (DZL), Cardio Pulmonary Institute (CPI), Giessen, Germany
| | - Anna Zakrzewicz
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University Giessen, German Centre for Lung Research (DZL), Cardio Pulmonary Institute (CPI), Giessen, Germany
| | - Juliane Liese
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University Giessen, German Centre for Lung Research (DZL), Cardio Pulmonary Institute (CPI), Giessen, Germany
| | - Andreas Hecker
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University Giessen, German Centre for Lung Research (DZL), Cardio Pulmonary Institute (CPI), Giessen, Germany
| | - Sigrid Wilker
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University Giessen, German Centre for Lung Research (DZL), Cardio Pulmonary Institute (CPI), Giessen, Germany
| | - Sabine Stumpf
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University Giessen, German Centre for Lung Research (DZL), Cardio Pulmonary Institute (CPI), Giessen, Germany
| | | | - Marius Rohde
- Department of Paediatric Haematology and Oncology, Justus-Liebig-University, Giessen, Germany
| | - Axel Gödecke
- Institute of Cardiovascular Physiology, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Winfried Padberg
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University Giessen, German Centre for Lung Research (DZL), Cardio Pulmonary Institute (CPI), Giessen, Germany
| | - Ivan Manzini
- Department of Animal Physiology and Molecular Biomedicine, Justus-Liebig-University Giessen, Giessen, Germany
| | - Günther Schmalzing
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
| | - Veronika Grau
- Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, Justus-Liebig-University Giessen, German Centre for Lung Research (DZL), Cardio Pulmonary Institute (CPI), Giessen, Germany
| |
Collapse
|
2
|
Ruan J, Hu X, Liu Y, Han Z, Ruan Q. Vulnerability to chronic stress and the phenotypic heterogeneity of presbycusis with subjective tinnitus. Front Neurosci 2022; 16:1046095. [PMID: 36620444 PMCID: PMC9812577 DOI: 10.3389/fnins.2022.1046095] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 12/02/2022] [Indexed: 12/24/2022] Open
Abstract
Age-related functional reserve decline and vulnerability of multiple physiological systems and organs, as well as at the cellular and molecular levels, result in different frailty phenotypes, such as physical, cognitive, and psychosocial frailty, and multiple comorbidities, including age-related hearing loss (ARHL) and/or tinnitus due to the decline in auditory reserve. However, the contributions of chronic non-audiogenic cumulative exposure, and chronic audiogenic stress to phenotypic heterogeneity of presbycusis and/or tinnitus remain elusive. Because of the cumulative environmental stressors throughout life, allostasis systems, the hypothalamus-pituitary-adrenal (HPA) and the sympathetic adrenal-medullary (SAM) axes become dysregulated and less able to maintain homeostasis, which leads to allostatic load and maladaptation. Brain-body communication via the neuroendocrine system promotes systemic chronic inflammation, overmobilization of energetic substances (glucose and lipids), and neuroplastic changes via the non-genomic and genomic actions of glucocorticoids, catecholamines, and their receptors. These systemic maladaptive alterations might lead to different frailty phenotypes and physical, cognitive, and psychological comorbidities, which, in turn, cause and exacerbate ARHL and/or tinnitus with phenotypic heterogeneity. Chronic audiogenic stressors, including aging accompanying ontological diseases, cumulative noise exposure, and ototoxic drugs as well as tinnitus, activate the HPA axis and SAM directly and indirectly by the amygdala, promoting allostatic load and maladaptive neuroplasticity in the auditory system and other vulnerable brain regions, such as the hippocampus, amygdala, and medial prefrontal cortex (mPFC). In the auditory system, peripheral deafferentation, central disinhibition, and tonotopic map reorganization may trigger tinnitus. Cross-modal maladaptive neuroplasticity between the auditory and other sensory systems is involved in tinnitus modulation. Persistent dendritic growth and formation, reduction in GABAergic inhibitory synaptic inputs induced by chronic audiogenic stresses in the amygdala, and increased dendritic atrophy in the hippocampus and mPFC, might involve the enhancement of attentional processing and long-term memory storage of chronic subjective tinnitus, accompanied by cognitive impairments and emotional comorbidities. Therefore, presbycusis and tinnitus are multisystem disorders with phenotypic heterogeneity. Stressors play a critical role in the phenotypic heterogeneity of presbycusis. Differential diagnosis based on biomarkers of metabonomics study, and interventions tailored to different ARHL phenotypes and/or tinnitus will contribute to healthy aging and improvement in the quality of life.
Collapse
Affiliation(s)
- Jian Ruan
- Department of Otolaryngology, Huadong Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xiuhua Hu
- Laboratory of Aging, Anti-aging & Cognitive Performance, Shanghai Institute of Geriatrics and Gerontology, Huadong Hospital, Fudan University, Shanghai, China,Shanghai Key Laboratory of Clinical Geriatrics, Research Center of Aging and Medicine, Huadong Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yuehong Liu
- Department of Otolaryngology, Huadong Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zhao Han
- Department of Otolaryngology, Huadong Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Qingwei Ruan
- Laboratory of Aging, Anti-aging & Cognitive Performance, Shanghai Institute of Geriatrics and Gerontology, Huadong Hospital, Fudan University, Shanghai, China,Shanghai Key Laboratory of Clinical Geriatrics, Research Center of Aging and Medicine, Huadong Hospital, Shanghai Medical College, Fudan University, Shanghai, China,*Correspondence: Qingwei Ruan,
| |
Collapse
|
3
|
Kem WR, Olincy A, Johnson L, Harris J, Wagner BD, Buchanan RW, Christians U, Freedman R. Pharmacokinetic Limitations on Effects of an Alpha7-Nicotinic Receptor Agonist in Schizophrenia: Randomized Trial with an Extended-Release Formulation. Neuropsychopharmacology 2018; 43:583-589. [PMID: 28825423 PMCID: PMC5770760 DOI: 10.1038/npp.2017.182] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 08/10/2017] [Accepted: 08/14/2017] [Indexed: 11/09/2022]
Abstract
The aim of the trial was to assess whether extending plasma levels of the alpha7-nicotinic acetylcholine receptor (nAChR) agonist 3-(2,4-dimethoxybenzylidene)-anabaseine (DMXB-A) over time enhances its cognitive effects in schizophrenia. Both smoking and non-smoking patients were studied, to determine whether effects differ between these two groups. Forty-three smokers and thirty-seven non-smokers who met DSM-IV criteria for schizophrenia were enrolled in a double-blind, randomized, placebo-controlled 1 month trial. DMXB-A 150 mg was formulated with hypromellose to produce extended release over 4 h and administered four times daily. The primary outcome (the Neurocognitive Composite of the MATRICS Consensus Cognitive Battery) and secondary outcomes (the MATRICS Attention-Vigilance Domain and P50 gating), showed no significant effect. Plasma levels were obtained 2.5 h post administration. In non-smokers, levels were similar to those reached transiently with 75-150 mg DMXB-A immediate-release formulations twice daily, which were earlier shown to be effective doses. However, the extended-release formulation produced no cognitive or clinical effect either in non-smokers or smokers. The 10-fold lower DMXB-A plasma levels in smokers suggest that chronic smoking enhances DMXB-A metabolism. Pro-cognitive effects of DMXB-A may result from transient increases in cell signaling that are limited by receptor tachyphylaxis. Future efforts to improve cognition in schizophrenia by enhancing alpha7 nAChR function may require consideration of these pharmacokinetic limitations.
Collapse
Affiliation(s)
- William R Kem
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, FL, USA
| | - Ann Olincy
- Department of Psychiatry F-546, University of Colorado School of Medicine, Aurora, CO, USA
| | - Lynn Johnson
- Department of Psychiatry F-546, University of Colorado School of Medicine, Aurora, CO, USA
| | - Josette Harris
- Department of Psychiatry F-546, University of Colorado School of Medicine, Aurora, CO, USA
| | - Brandie D Wagner
- Department of Biostatistics and Informatics, Colorado School of Public Health, Aurora, CO, USA
| | - Robert W Buchanan
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Uwe Christians
- Department of Anesthesiology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Robert Freedman
- Department of Psychiatry F-546, University of Colorado School of Medicine, Aurora, CO, USA,Department of Psychiatry F-546, University of Colorado School of Medicine Anschutz Medical Campus, Box C-268-71, Aurora, CO 80045, USA, Tel: +720 224 4638, Fax: +303 724 4956, E-mail:
| |
Collapse
|
4
|
Bertrand D, Lee CHL, Flood D, Marger F, Donnelly-Roberts D. Therapeutic Potential of α7 Nicotinic Acetylcholine Receptors. Pharmacol Rev 2015; 67:1025-73. [DOI: 10.1124/pr.113.008581] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
|
5
|
Featherstone RE, Siegel SJ. The Role of Nicotine in Schizophrenia. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2015; 124:23-78. [PMID: 26472525 DOI: 10.1016/bs.irn.2015.07.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Schizophrenia is associated with by severe disruptions in thought, cognition, emotion, and behavior. Patients show a marked increase in rates of smoking and nicotine dependence relative to nonaffected individuals, a finding commonly ascribed to the potential ameliorative effects of nicotine on symptom severity and cognitive impairment. Indeed, many studies have demonstrated improvement in patients following the administration of nicotine. Such findings have led to an increased emphasis on the development of therapeutic agents to target the nicotinic system as well as increasing the impetus to understand the genetic basis for nicotinic dysfunction in schizophrenia. The goal of this review article is to provide a critical summary of evidence for the role of the nicotinic system in schizophrenia. The first part will review the role of nicotine in normalization of primary dysfunctions and endophenotypical changes found in schizophrenia. The second part will provide a summary of genetic evidence linking polymorphisms in nicotinic receptor genes to smoking and schizophrenia. The third part will summarize attempts to treat schizophrenia using agents specifically targeting nicotinic and nicotinic receptor subtypes. Although currently available antipsychotic treatments are generally able to manage some aspects of schizophrenia (e.g., positive symptoms) they fail to address several other critically effected aspects of the disease. As such, the search for novel mechanisms to treat this disease is necessary.
Collapse
Affiliation(s)
- Robert E Featherstone
- Translational Neuroscience Program, Department of Psychiatry, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| | - Steven J Siegel
- Translational Neuroscience Program, Department of Psychiatry, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| |
Collapse
|
6
|
Knott V, Smith D, de la Salle S, Impey D, Choueiry J, Beaudry E, Smith M, Saghir S, Ilivitsky V, Labelle A. CDP-choline: effects of the procholine supplement on sensory gating and executive function in healthy volunteers stratified for low, medium and high P50 suppression. J Psychopharmacol 2014; 28:1095-108. [PMID: 25315828 DOI: 10.1177/0269881114553254] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Diminished auditory sensory gating and associated neurocognitive deficits in schizophrenia have been linked to altered expression and function of the alpha-7 nicotinic acetycholinergic receptor (α7 nAChR), the targeting of which may have treatment potential. Choline is a selective α7 nAChR agonist and the aim of this study was to determine whether cytidine 5'-diphosphocholine (CDP-choline), or citicoline, a dietary source of choline, increases sensory gating and cognition in healthy volunteers stratified for gating level. In a randomized, placebo-controlled, double-blind design involving acute administration of low, moderate doses (500 mg, 1000 mg) of CDP-choline, 24 healthy volunteers were assessed for auditory gating as indexed by suppression of the P50 event-related potential (ERP) in a paired-stimulus (S1, S2) paradigm, and for executive function as measured by the Groton Maze Learning Task (GMLT) of the CogState Schizophrenia Battery. CDP-choline improved gating (1000 mg) and suppression of the S2 P50 response (500 mg, 1000 mg), with the effects being selective for individuals with low gating (suppression) levels. Tentative support was also shown for increased GMLT performance (500 mg) in low suppressors. These preliminary findings with CDP-choline in a healthy, schizophrenia-like surrogate sample are consistent with a α7 nAChR mechanism and support further trials with choline as a pro-cognitive strategy.
Collapse
Affiliation(s)
- Verner Knott
- Institute of Mental Health Research, University of Ottawa, Ottawa, ON, Canada Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada School of Psychology, University of Ottawa, Ottawa, ON, Canada Department of Psychiatry, University of Ottawa, Ottawa, ON, Canada
| | - Dylan Smith
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | | | - Danielle Impey
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
| | - Joelle Choueiry
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Elise Beaudry
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
| | - Meaghan Smith
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
| | - Salman Saghir
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
| | - Vadim Ilivitsky
- Department of Psychiatry, University of Ottawa, Ottawa, ON, Canada
| | - Alain Labelle
- Department of Psychiatry, University of Ottawa, Ottawa, ON, Canada
| |
Collapse
|
7
|
Freedman R. α7-Nicotinic Acetylcholine Receptor Agonists for Cognitive Enhancement in Schizophrenia. Annu Rev Med 2014; 65:245-61. [DOI: 10.1146/annurev-med-092112-142937] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Robert Freedman
- Department of Psychiatry, University of Colorado Denver School of Medicine, Aurora, Colorado 80045;
| |
Collapse
|
8
|
Effects of L-arginine and N(ω)-nitro-L-arginine methylester on learning and memory and α7 nAChR expression in the prefrontal cortex and hippocampus of rats. Neurosci Bull 2013; 29:303-10. [PMID: 23575895 DOI: 10.1007/s12264-013-1331-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 10/23/2012] [Indexed: 12/22/2022] Open
Abstract
Nitric oxide (NO) is a novel type of neurotransmitter that is closely associated with synaptic plasticity, learning and memory. In the present study, we assessed the effects of L-arginine and N(ω)-nitro-L-arginine methylester (L-NAME, a nitric oxide synthase inhibitor) on learning and memory. Rats were assigned to three groups receiving intracerebroventricular injections of L-Arg (the NO precursor), L-NAME, or 0.9% NaCl (control), once daily for seven consecutive days. Twelve hours after the last injection, they underwent an electric shock-paired Y maze test. Twenty-four hours later, the rats' memory of the safe illuminated arm was tested. After that, the levels of NO and α7 nicotinic acetylcholine receptor (α7 nAChR) in the prefrontal cortex and hippocampus were assessed using an NO assay kit, and immunohistochemistry and Western blots, respectively. We found that, compared to controls, L-Arg-treated rats received fewer foot shocks and made fewer errors to reach the learning criterion, and made fewer errors during the memory-testing session. In contrast, L-NAME-treated rats received more foot shocks and made more errors than controls to reach the learning criterion, and made more errors during the memory-testing session. In parallel, NO content in the prefrontal cortex and hippocampus was higher in L-Arg-treated rats and lower in L-NAME rats, compared to controls. Similarly, α7 nAChR immunoreactivity and protein expression in the prefrontal cortex and hippocampus were higher in L-Arg-treated rats and lower in L-NAME rats, compared to controls. These results suggest that the modulation of NO content in the brain correlates with α7 nAChR distribution and expression in the prefrontal cortex and hippocampus, as well as with learning and memory performance in the Y-maze.
Collapse
|
9
|
Respiratory related evoked potential measures of cerebral cortical respiratory information processing. Biol Psychol 2010; 84:4-12. [DOI: 10.1016/j.biopsycho.2010.02.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 01/28/2010] [Accepted: 02/10/2010] [Indexed: 11/22/2022]
|
10
|
Abstract
Central sensory filtering processes can be demonstrated using a paired stimulus paradigm. Normal humans show a diminished, vertex-recorded mid-latency (50 ms) of auditory evoked potential to the second of paired clicks (0.5 s apart), a phenomenon termed as auditory gating. A loss of 50 ms in auditory gating is strongly related to psychosis. The N40 auditory evoked potential (EP) in rats has been used to develop an animal model for the study of sensory gating mechanisms. Previous animal studies of auditory gating have used psychotomimetic drug administration to induce sensory gating. However, a nonpharmacologic model of deficient gating would be advantageous. In the present study we investigated the effect of immobilization stress on sensory gating in twelve adult male mice. Evoked responses to the paired auditory click stimuli from vertex location of scalp were recorded using a silver needle electrode, a bioelectric amplifier, and an analog-digital converter. The mice were exposed to immobilization stress (IS) for 3 h. Data showed that the N40 potential was depressed in response to the second of the paired stimuli before application immobilization stress. At the end of the 3-h immobilization, the depression of the second N40 response was not observed. It was concluded that sensory gating is present in the mice and acutely disrupted by stressful stimuli, as shown in human subjects and rats.
Collapse
Affiliation(s)
- Cem Süer
- University of Erciyes, Faculty of Medicine, Department of Physiology, 38039 Kayseri, Turkey
| | | | | |
Collapse
|
11
|
Rőszer T, Józsa T, Szentmiklósi AJ, Bánfalvi G. Acetylcholine inhibits nitric oxide (NO) synthesis in the gastropod nervous system. Cell Tissue Res 2009; 336:325-35. [DOI: 10.1007/s00441-009-0764-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Accepted: 01/13/2009] [Indexed: 12/16/2022]
|
12
|
Martin LF, Freedman R. Schizophrenia and the alpha7 nicotinic acetylcholine receptor. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2007; 78:225-46. [PMID: 17349863 DOI: 10.1016/s0074-7742(06)78008-4] [Citation(s) in RCA: 167] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
In addition to the devastating symptoms of psychosis, many people with schizophrenia also suffer from cognitive impairment. These cognitive symptoms lead to marked dysfunction and can impact employability, treatment adherence, and social skills. Deficits in P50 auditory gating are associated with attentional impairment and may contribute to cognitive symptoms and perceptual disturbances. This nicotinic cholinergic-mediated inhibitory process represents a potential new target for therapeutic intervention in schizophrenia. This chapter will review evidence implicating the nicotinic cholinergic, and specifically, the alpha7 nicotinic receptor system in the pathology of schizophrenia. Impaired auditory sensory gating has been linked to the alpha7 nicotinic receptor gene on the chromosome 15q14 locus. A majority of persons with schizophrenia are heavy smokers. Although nicotine can acutely reverse diminished auditory sensory gating in people with schizophrenia, this effect is lost on a chronic basis due to receptor desensitization. The alpha7 nicotinic agonist 3-(2,4 dimethoxy)benzylidene-anabaseine (DMXBA) can also enhance auditory sensory gating in animal models. DMXBA is well tolerated in humans and a new study in persons with schizophrenia has found that DMXBA enhances both P50 auditory gating and cognition. alpha7 Nicotinic acetylcholine receptor agonists appear to be viable candidates for the treatment of cognitive disturbances in schizophrenia.
Collapse
Affiliation(s)
- Laura F Martin
- Research Service, VA Eastern Colorado Health Care System, Denver, Colorado 80220, USA
| | | |
Collapse
|
13
|
Hogg RC, Bertrand D. Partial agonists as therapeutic agents at neuronal nicotinic acetylcholine receptors. Biochem Pharmacol 2006; 73:459-68. [PMID: 16979139 DOI: 10.1016/j.bcp.2006.08.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2006] [Revised: 08/04/2006] [Accepted: 08/10/2006] [Indexed: 11/30/2022]
Abstract
Improved understanding of how brain function is altered in neurodegenerative disease states, pain and conditions, such as schizophrenia and attention deficit disorder, has highlighted the role of nicotinic acetylcholine receptors (nAChRs) in these conditions and identified them as promising therapeutic targets. nAChRs are widely expressed throughout the peripheral and central nervous system, and this widespread nature underlines the need for new ligands with different selectivities and pharmacological profiles if we are to avoid the adverse side effects associated with many of the nAChR modulators currently identified. Partial agonists have the unique property of being able to act both as agonists or antagonists depending on the concentration of endogenous neurotransmitter. Moreover, the agonist action of partial agonists has a 'ceiling' effect, giving them a large safety margin and making them an attractive proposition for therapeutic molecules. Partial agonists of nAChRs are currently being developed as a nicotine replacement therapy for smoking cessation and for the treatment of a number of neurological diseases associated with a loss of cholinergic function. This commentary will discuss the pharmacological properties of partial agonists and review recent research developments in the field of partial agonists acting at nicotinic receptors.
Collapse
Affiliation(s)
- Ron C Hogg
- Department of Neurosciences, Medical Faculty, CMU, 1 rue Michel Servet, CH-1211 Geneva 4, Switzerland.
| | | |
Collapse
|
14
|
Gauthier M, Dacher M, Thany SH, Niggebrügge C, Déglise P, Kljucevic P, Armengaud C, Grünewald B. Involvement of α-bungarotoxin-sensitive nicotinic receptors in long-term memory formation in the honeybee (Apis mellifera). Neurobiol Learn Mem 2006; 86:164-74. [PMID: 16616529 DOI: 10.1016/j.nlm.2006.02.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Revised: 02/16/2006] [Accepted: 02/22/2006] [Indexed: 11/18/2022]
Abstract
In the honeybee Apis mellifera, multiple-trial olfactory conditioning of the proboscis extension response specifically leads to long-term memory (LTM) which can be retrieved more than 24 h after learning. We studied the involvement of nicotinic acetylcholine receptors in the establishment of LTM by injecting the nicotinic antagonists mecamylamine (1 mM), alpha-bungarotoxin (alpha-BGT, 0.1 mM) or methyllycaconitine (MLA, 0.1 mM) into the brain through the median ocellus 20 min before or 20 min after multiple-trial learning. The retention tests were performed 1, 3, and 24 h after learning. Pre-training injections of mecamylamine induced a lower performance during conditioning but had no effect on LTM formation. Post-training injections of mecamylamine did not affect honeybees' performances. Pre-training injections of MLA or post-training injection of alpha-BGT specifically induced LTM impairment whereas acquisition as well as memory retrieval tested 1 or 3 h after learning was normal. This indicates that brain injections of alpha-BGT and MLA did not interfere with learning or medium-term memory. Rather, these blockers affect the LTM. To explain these results, we advance the hypothesis that honeybee alpha-BGT-sensitive acetylcholine receptors are also sensitive to MLA. These receptors could be essential for triggering intracellular mechanisms involved in LTM. By contrast, medium-term memory is not dependent upon these receptors but is affected by mecamylamine.
Collapse
Affiliation(s)
- Monique Gauthier
- Centre de Recherches sur la Cognition Animale, CNRS/Université Paul Sabatier Toulouse III, 4R3, 118 route de Narbonne, 31062 Toulouse Cedex 09, France.
| | | | | | | | | | | | | | | |
Collapse
|
15
|
The Nemertine Toxin Anabaseine and Its Derivative DMXBA (GTS-21): Chemical and Pharmacological Properties. Mar Drugs 2006. [DOI: 10.3390/md403255] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
16
|
Freedman R, Ross R, Leonard S, Myles-Worsley M, Adams CE, Waldo M, Tregellas J, Martin L, Olincy A, Tanabe J, Kisley MA, Hunter S, Stevens KE. Early biomarkers of psychosis. DIALOGUES IN CLINICAL NEUROSCIENCE 2006. [PMID: 16060593 PMCID: PMC3181722 DOI: 10.31887/dcns.2005.7.1/frreedman] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Biological traits that are predictive of the later development of psychosis have not yet been identified. The complex, multidetermined nature of schizophrenia and other psychoses makes it unlikely that any single biomarker will be both sensitive and specific enough to unambiguously identify individuals who will later become psychotic. However, current genetic research has begun to identify genes associated with schizophrenia, some of which have phenotypes that appear early in life. While these phenotypes have low predictive power for identifying individuals who will become psychotic, they do serve as biomarkers for pathophysiological processes that can become the targets of prevention strategies. Examples are given from work on the role of the alpha(T)nicotinic receptor and its gene CHRNA7 on chromosome 15 in the neurobiology and genetic transmission of schizophrenia.
Collapse
Affiliation(s)
- Robert Freedman
- Department of Psychiatry C-268-71, University of Colorado Health Sciences Center, Denver, CO 80262, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
|
18
|
Martin LF, Kem WR, Freedman R. Alpha-7 nicotinic receptor agonists: potential new candidates for the treatment of schizophrenia. Psychopharmacology (Berl) 2004; 174:54-64. [PMID: 15205879 DOI: 10.1007/s00213-003-1750-1] [Citation(s) in RCA: 266] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2003] [Accepted: 11/28/2003] [Indexed: 01/16/2023]
Abstract
RATIONALE AND OBJECTIVE Auditory sensory gating, a biological measurement of the ability to suppress the evoked response to the second of two auditory stimuli, is diminished in people with schizophrenia. Deficits in sensory gating are associated with attentional impairment, and may contribute to cognitive symptoms and perceptual disturbances. This inhibitory process, which involves the alpha(7) nicotinic receptor mediated release of gamma-aminobutyric acid (GABA) by hippocampal interneurons, represents a potential new target for therapeutic intervention in schizophrenia. METHOD This paper will review several lines of evidence implicating the nicotinic-cholinergic, and specifically, the alpha(7) nicotinic receptor system in the pathology of schizophrenia and the evidence that alpha(7) nicotinic receptor agonists may ameliorate some of these deficits. RESULTS Impaired auditory sensory gating has been linked to the alpha(7) nicotinic receptor gene on the chromosome 15q14 locus. Single nucleotide polymorphisms of the promoter region of this gene are more frequent in people with schizophrenia. Although nicotine can acutely reverse diminished auditory sensory gating in people with schizophrenia, this effect is lost on a chronic basis due to receptor desensitization. Clozapine is able to reverse auditory sensory gating impairment, probably through an alpha(7) nicotinic receptor mechanism, in both humans and animal models with repeated dosing. The alpha(7) nicotinic agonist 3-2,4 dimethoxybenzylidene anabaseine (DMXBA) can also enhance auditory sensory gating in animal models. DMXBA is well tolerated in humans and improves several cognitive measures. CONCLUSION Alpha-7 nicotinic receptor agonists appear to be reasonable candidates for the treatment of cognitive and perceptual disturbances in schizophrenia.
Collapse
Affiliation(s)
- Laura F Martin
- Department of Psychiatry, Department of Veterans Affairs and University of Colorado Health Sciences Center, 4200 East Ninth Avenue, C268-71, Denver, CO 80262, USA.
| | | | | |
Collapse
|
19
|
Schilström B, Mameli-Engvall M, Rawal N, Grillner P, Jardemark K, Svensson TH. Nitric oxide is involved in nicotine-induced burst firing of rat ventral tegmental area dopamine neurons. Neuroscience 2004; 125:957-64. [PMID: 15120855 DOI: 10.1016/j.neuroscience.2003.12.021] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2003] [Indexed: 11/15/2022]
Abstract
In the present study, using single cell recordings in vivo and intracellular recordings in vitro from midbrain slices, the role of N-methyl-d-aspartate (NMDA) receptor signaling on firing activity in ventral tegmental area dopamine neurons elicited by nicotine was investigated in the rat. In accordance with previous studies, systemic nicotine (0.5 mg/kg s.c.) increased both firing rate and burst firing of dopamine neurons in vivo, and bath-applied nicotine (10 microM) increased firing rate in vitro. The competitive NMDA receptor antagonist CGP39551 (2.5 mg/kg i.p.) inhibited nicotine's effects on burst firing and also attenuated the nicotine-induced increase in firing rate. Moreover, although the nitric oxide (NO)-synthase inhibitor N-nitro-l-arginine-methyl-ester (l-NAME; 5.0 mg/kg i.p.) had no effect on cell firing by itself, it prevented the response to nicotine in vivo. In contrast, l-NAME (100 microM) did not influence nicotine's effect on dopamine cell firing in vitro, suggesting that the effect of l-NAME seen in vivo is dependent on presynaptic afferent input. The present study confirms previous results suggesting that the effect of systemically administered nicotine is in part presynaptic and mediated via NMDA receptors. The data also indicate that NO plays an important role in the previously demonstrated, indirect, glutamate-mediated excitation of these neurons by nicotine. By inference, our results provide additional support for the involvement of NO in nicotine dependence.
Collapse
Affiliation(s)
- B Schilström
- Karolinska Institutet, Department of Physiology and Pharmacology, Section of Neuropsychopharmacology, Nanna Svartz väg 2, S-171 77 Stockholm, Sweden
| | | | | | | | | | | |
Collapse
|
20
|
Weruaga E, Balkan B, Koylu EO, Pogun S, Alonso JR. Effects of chronic nicotine administration on nitric oxide synthase expression and activity in rat brain. J Neurosci Res 2002; 67:689-97. [PMID: 11891781 DOI: 10.1002/jnr.10158] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although there is substantial evidence concerning the influence of nicotine on nitric oxide (NO) synthesis in the vascular system, there are fewer studies concerning the central nervous system. Although NO metabolites (nitrates/nitrites) increase in several rat brain regions after chronic injection of nicotine, the cellular origin of this rise in NO levels is not known. The aim of the present work was to assess the effects of repetitive nicotine administration on nitric oxide synthase (NOS) expression and activity in male and female rat brains. To determine levels of nitrate/nitrite, the Griess reaction was carried out in tissue micropunched from the frontal cortex, striatum, and accumbens of both male and female rats untreated (naïve) or injected with saline or nicotine (0.4 mg/kg for 15 days). In parallel, coronal sections of fixed brains from equally treated animals were immunostained for neuronal NOS or histochemically labelled for NADPH-diaphorase activity. Nicotine treatment increased NO metabolites significantly in all brain regions compared with naïve or saline-treated rats. By contrast, analysis of the planimetric counting of NOS/NADPH-diaphorase-positive neurons failed to demonstrate any significant effect of the nicotine treatment. A significant decrease was observed with both techniques employed in saline-injected female rats compared with naïve animals, suggesting a stress response. The mismatch between the biochemical and the histological data after chronic nicotine treatment is discussed. The up-regulation of NO sources other than neurons is proposed.
Collapse
Affiliation(s)
- Eduardo Weruaga
- Department of Cell Biology and Pathology and Institute for Neuroscience of Castilla y León, University of Salamanca, Salamanca, Spain
| | | | | | | | | |
Collapse
|
21
|
Azuma R, Komuro M, Kawaguchi Y, Okudaira K, Hayashi M, Kiwada H. Comparative Analysis of In Vitro and In Vivo Pharmacokinetic Parameters Related to Individual Variability of GTS-21 in Canine. Drug Metab Pharmacokinet 2002; 17:75-82. [PMID: 15618655 DOI: 10.2133/dmpk.17.75] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To clarify the cause of the canine individual variability in plasma concentration after oral administration of GTS-21, we evaluated in vitro the metabolism to 4-OH-GTS-21 in liver microsomes of the same individuals from in vivo pharmacokinetic study. First, we applied to the Michaelis-Menten kinetic parameters to a dispersion model, and compared hepatic availability (F(H)) and hepatic clearance (CL(H)) values from in vitro with bioavailability (F), hepatic plasma flow (Q(PH)), and plasma clearance (CL(P)) values from in vivo. The ratios of CL(H) to Q(PH) were ranged 0.74 to 0.94, suggesting that GTS-21 is a hepatic plasma flow-limiting drug. A significant correlation of F(H) and F in the four dogs (r=0.995, p=0.005) indicates that the variability is predominantly caused by GTS-21 O4-demethylase activity. Second, we specified the cytochrome P450 (CYP) enzymes that are involved with the metabolism by chemical inhibition. alpha-Naphthoflavone, furafylline, quinidine, quinine, and troleandomycin significantly inhibited GTS-21 O4-demethylase activity. Thus CYP1A, CYP2D15, and CYP3A12 were involved with O4-demethylation. The variability in control activity decreased on addition of alpha-naphthoflavone and furafylline. Third, we quantified the contents of CYP1A and CYP3A12 by enzyme-linked immunosorbent assay. The content of CYP1A was consistent with GTS-21 O4-demethylase activity. We concluded that canine liver CYP1A causes the individual variability in GTS-21 plasma concentration after oral administration.
Collapse
Affiliation(s)
- Ryotaro Azuma
- Pharmacokinetics Research Lab, Taiho Pharmaceutical Co., Ltd., Tokushima, Japan.
| | | | | | | | | | | |
Collapse
|
22
|
Azuma R, Hirota T, Manabe H, Komuro M, Kiwada H. First-pass of GTS-21 on canine gut wall and liver determined by portal-systemic concentration difference. Eur J Pharm Sci 2001; 14:159-65. [PMID: 11500261 DOI: 10.1016/s0928-0987(01)00166-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To clarify the cause of the canine individual variability of plasma concentration after oral administration of GTS-21 [(E)-3-(2,4-dimethoxybenzylidene)-3,4,5,6-tetra-hydro-2,3'-bipyridine dihydrochloride], we evaluated the absorption ratio (F(A)), intestinal availability (F(G)), and hepatic availability (F(H)). The bioavailability (F) was evaluated from the ratio of the area under the plasma concentration versus time curves after oral and intravenous administration. Three isoflurane anaesthetised dogs were fitted with an electromagnetic flow probe attached to the portal vein and cannulated through the portal and the femoral veins. After intraduodenal administration of GTS-21, both plasma concentrations were determined simultaneously. F(A) x F(G) was calculated from the portal-systemic concentration difference taking into consideration the blood-plasma partition ratio. F(A) was calculated from the residual drug contents of the small intestine. F(H) was calculated by dividing F by F(A) x F(G). The F values were 0.072, 0.021, and 0.037, indicating an individual variability of ca. threefold. The F(A) values were close to 1, and the F(G) values ranged from 0.449 to 0.461. Accordingly, the F(H) values were estimated at 0.170, 0.047, and 0.083. GTS-21 was completely absorbed but lost by first-pass effects of passage through the gut wall and liver. The first-pass effect of liver is larger than that of the gut wall, and dominates the individual variability in plasma concentration.
Collapse
Affiliation(s)
- R Azuma
- Pharmacokinetics Research Laboratory, Taiho Pharmaceutical Co., Ltd., 224-2, Ebisuno, Hiraishi, Kawauchi-cho, Tokushima 771-0194, Japan.
| | | | | | | | | |
Collapse
|