51
|
Otvos RA, Mladic M, Arias-Alpizar G, Niessen WMA, Somsen GW, Smit AB, Kool J. At-Line Cellular Screening Methodology for Bioactives in Mixtures Targeting the α7-Nicotinic Acetylcholine Receptor. ACTA ACUST UNITED AC 2016; 21:459-67. [DOI: 10.1177/1087057115625307] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/11/2015] [Indexed: 01/03/2023]
Abstract
The α7-nicotinic acetylcholine receptor (α7-nAChR) is a ligand-gated ion channel expressed in different regions of the central nervous system (CNS). The α7-nAChR has been associated with Alzheimer’s disease, epilepsy, and schizophrenia, and therefore is extensively studied as a drug target for the treatment of these diseases. Important sources for new compounds in drug discovery are natural extracts. Since natural extracts are complex mixtures, identification of the bioactives demands the use of analytical techniques to separate a bioactive from inactive compounds. This study describes screening methodology for identifying bioactive compounds in mixtures acting on the α7-nAChR. The methodology developed combines liquid chromatography (LC) coupled via a split with both an at-line calcium (Ca2+)-flux assay and high-resolution mass spectrometry (MS). This allows evaluation of α7-nAChR responses after LC separation, while parallel MS enables compound identification. The methodology was optimized for analysis of agonists and positive allosteric modulators, and was successfully applied to screening of the hallucinogen mushroom Psilocybe Mckennaii. The crude mushroom extract was analyzed using both reversed-phase and hydrophilic interaction liquid chromatography. Matching retention times and peak shapes of bioactives found with data from the parallel MS measurements allowed rapid pinpointing of accurate masses corresponding to the bioactives.
Collapse
Affiliation(s)
- Reka A. Otvos
- AIMMS Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Department of Molecular and Cellular Neurobiology, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Marija Mladic
- AIMMS Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Gabriela Arias-Alpizar
- AIMMS Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Wilfried M. A. Niessen
- AIMMS Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- hyphen MassSpec, Warmond, the Netherlands
| | - Govert W. Somsen
- AIMMS Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - August B. Smit
- Department of Molecular and Cellular Neurobiology, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Jeroen Kool
- AIMMS Division of BioAnalytical Chemistry, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| |
Collapse
|
52
|
Besson M, Forget B. Cognitive Dysfunction, Affective States, and Vulnerability to Nicotine Addiction: A Multifactorial Perspective. Front Psychiatry 2016; 7:160. [PMID: 27708591 PMCID: PMC5030478 DOI: 10.3389/fpsyt.2016.00160] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 09/06/2016] [Indexed: 11/17/2022] Open
Abstract
Although smoking prevalence has declined in recent years, certain subpopulations continue to smoke at disproportionately high rates and show resistance to cessation treatments. Individuals showing cognitive and affective impairments, including emotional distress and deficits in attention, memory, and inhibitory control, particularly in the context of psychiatric conditions, such as attention-deficit hyperactivity disorder, schizophrenia, and mood disorders, are at higher risk for tobacco addiction. Nicotine has been shown to improve cognitive and emotional processing in some conditions, including during tobacco abstinence. Self-medication of cognitive deficits or negative affect has been proposed to underlie high rates of tobacco smoking among people with psychiatric disorders. However, pre-existing cognitive and mood disorders may also influence the development and maintenance of nicotine dependence, by biasing nicotine-induced alterations in information processing and associative learning, decision-making, and inhibitory control. Here, we discuss the potential forms of contribution of cognitive and affective deficits to nicotine addiction-related processes, by reviewing major clinical and preclinical studies investigating either the procognitive and therapeutic action of nicotine or the putative primary role of cognitive and emotional impairments in addiction-like features.
Collapse
Affiliation(s)
- Morgane Besson
- Unité de Neurobiologie Intégrative des Systèmes Cholinergiques, Department of Neuroscience, CNRS UMR 3571, Institut Pasteur , Paris , France
| | - Benoît Forget
- Unité de Neurobiologie Intégrative des Systèmes Cholinergiques, Department of Neuroscience, CNRS UMR 3571, Institut Pasteur , Paris , France
| |
Collapse
|
53
|
Brunelin J, Hasan A, Haesebaert F, Nitsche MA, Poulet E. Nicotine Smoking Prevents the Effects of Frontotemporal Transcranial Direct Current Stimulation (tDCS) in Hallucinating Patients With Schizophrenia. Brain Stimul 2015; 8:1225-7. [DOI: 10.1016/j.brs.2015.08.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 08/05/2015] [Indexed: 12/27/2022] Open
|
54
|
Abstract
Recent neuroimaging studies have demonstrated that cigarette smoking is associated with changed brain structure and function. However, little is known about alterations of the topological organization of brain functional networks in heavy smokers. Thirty-one heavy smokers and 33 non-smokers underwent a resting-state functional magnetic resonance imaging scan. The whole-brain functional networks were constructed by thresholding the correlation matrices of 90 brain regions and their topological properties were analyzed using graph network analysis. Non-parametric permutation tests were performed to investigate group differences in network topological measures and multiple regression analysis was conducted to determine the relationships between the network metrics and smoking-related variables. Both heavy smokers and non-smokers exhibited small-world architecture in their brain functional networks. Compared with non-smokers, however, heavy smokers showed altered topological measurements characterized by lower global efficiency, higher local efficiency and clustering coefficients and greater path length. Furthermore, heavy smokers demonstrated decreased nodal global efficiency mainly in brain regions within the default mode network, whereas increased nodal local efficiency predominated in the visual-related regions. In addition, heavy smokers exhibited an association between the altered network metrics and the duration of cigarette use or the severity of nicotine dependence. Our results suggest that heavy smokers may have less efficient network architecture in the brain, and chronic cigarette smoking is associated with disruptions in the topological organization of brain networks. Our findings may further the understanding of the effects of chronic cigarette smoking on the brain and the pathophysiological mechanisms underlying nicotine dependence.
Collapse
Affiliation(s)
- Fuchun Lin
- Wuhan Center for Magnetic Resonance; State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics; Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences; China
| | - Guangyao Wu
- Department of Magnetic Resonance Imaging; Zhongnan Hospital, Wuhan University; China
| | - Ling Zhu
- Department of Magnetic Resonance Imaging; Zhongnan Hospital, Wuhan University; China
| | - Hao Lei
- Wuhan Center for Magnetic Resonance; State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics; Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences; China
| |
Collapse
|
55
|
Jørgensen KN, Psychol C, Skjærvø I, Mørch-Johnsen L, Haukvik UK, Lange EH, Melle I, Andreassen OA, Agartz I. Cigarette smoking is associated with thinner cingulate and insular cortices in patients with severe mental illness. J Psychiatry Neurosci 2015; 40:241-9. [PMID: 25672482 PMCID: PMC4478057 DOI: 10.1503/jpn.140163] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 10/07/2014] [Accepted: 11/28/2014] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Magnetic resonance imaging (MRI) studies show reduced cortical thickness in patients with schizophrenia and bipolar disorder. These subtle brain abnormalities may provide insight into illness mechanisms. However, environmental and lifestyle-related factors, such as cigarette smoking, may contribute to brain structure changes. Cigarette smoking is highly prevalent in patients with severe mental illness. In nonpsychiatric samples, smoking has been associated with reduced thickness in the anterior (ACC) and posterior cingulate cortices, the insular cortex (INS), the dorsolateral prefrontal cortex and the orbitofrontal cortex. METHODS We examined MRI scans from patients with schizophrenia, other psychotic disorders or bipolar disorder and healthy controls using FreeSurfer. RESULTS We included 506 patients (49% smokers) and 237 controls (20% smokers) in our study. We found reduced cortical thickness in the left rostral ACC and the left INS in smoking patients compared with nonsmoking patients, but this difference was not found among healthy controls. No dose-response relationship was found between amount of smoking and cortical thickness in these regions. Among patients, maps of thickness along the whole cortical surface revealed reduced insular thickness but no effects in other regions. Among healthy controls, similar analyses revealed increased age-related cortical thinning in the left occipital lobe among smokers compared with nonsmokers. LIMITATIONS The causal direction could not be determined owing to the cross-sectional design and lack of detailed data on smoking addiction and smoking history. CONCLUSION The effect of cigarette smoking should be considered in MRI studies of patients with severe mental illness.
Collapse
Affiliation(s)
- Kjetil Nordbø Jørgensen
- Department of Psychiatric Research, Diakonhjemmet Hospital, (Jørgensen, Skjærvø, Mørch-Johnsen, Haukvik, Lange, Agartz); NORMENT and K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo (Jørgensen, Mørch-Johnsen, Haukvik, Lange, Melle, Andreassen, Agartz); the Norwegian Centre for Addiction Research (SERAF), Institute of Clinical Medicine, University of Oslo (Skjærvø); and the Division of Mental Health and Addiction, Oslo University Hospital (Melle, Andreassen), Oslo, Norway
| | | | | | - Lynn Mørch-Johnsen
- Department of Psychiatric Research, Diakonhjemmet Hospital, (Jørgensen, Skjærvø, Mørch-Johnsen, Haukvik, Lange, Agartz); NORMENT and K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo (Jørgensen, Mørch-Johnsen, Haukvik, Lange, Melle, Andreassen, Agartz); the Norwegian Centre for Addiction Research (SERAF), Institute of Clinical Medicine, University of Oslo (Skjærvø); and the Division of Mental Health and Addiction, Oslo University Hospital (Melle, Andreassen), Oslo, Norway
| | - Unn Kristin Haukvik
- Department of Psychiatric Research, Diakonhjemmet Hospital, (Jørgensen, Skjærvø, Mørch-Johnsen, Haukvik, Lange, Agartz); NORMENT and K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo (Jørgensen, Mørch-Johnsen, Haukvik, Lange, Melle, Andreassen, Agartz); the Norwegian Centre for Addiction Research (SERAF), Institute of Clinical Medicine, University of Oslo (Skjærvø); and the Division of Mental Health and Addiction, Oslo University Hospital (Melle, Andreassen), Oslo, Norway
| | - Elisabeth Heffermehl Lange
- Department of Psychiatric Research, Diakonhjemmet Hospital, (Jørgensen, Skjærvø, Mørch-Johnsen, Haukvik, Lange, Agartz); NORMENT and K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo (Jørgensen, Mørch-Johnsen, Haukvik, Lange, Melle, Andreassen, Agartz); the Norwegian Centre for Addiction Research (SERAF), Institute of Clinical Medicine, University of Oslo (Skjærvø); and the Division of Mental Health and Addiction, Oslo University Hospital (Melle, Andreassen), Oslo, Norway
| | - Ingrid Melle
- Department of Psychiatric Research, Diakonhjemmet Hospital, (Jørgensen, Skjærvø, Mørch-Johnsen, Haukvik, Lange, Agartz); NORMENT and K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo (Jørgensen, Mørch-Johnsen, Haukvik, Lange, Melle, Andreassen, Agartz); the Norwegian Centre for Addiction Research (SERAF), Institute of Clinical Medicine, University of Oslo (Skjærvø); and the Division of Mental Health and Addiction, Oslo University Hospital (Melle, Andreassen), Oslo, Norway
| | - Ole Andreas Andreassen
- Department of Psychiatric Research, Diakonhjemmet Hospital, (Jørgensen, Skjærvø, Mørch-Johnsen, Haukvik, Lange, Agartz); NORMENT and K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo (Jørgensen, Mørch-Johnsen, Haukvik, Lange, Melle, Andreassen, Agartz); the Norwegian Centre for Addiction Research (SERAF), Institute of Clinical Medicine, University of Oslo (Skjærvø); and the Division of Mental Health and Addiction, Oslo University Hospital (Melle, Andreassen), Oslo, Norway
| | - Ingrid Agartz
- Department of Psychiatric Research, Diakonhjemmet Hospital, (Jørgensen, Skjærvø, Mørch-Johnsen, Haukvik, Lange, Agartz); NORMENT and K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo (Jørgensen, Mørch-Johnsen, Haukvik, Lange, Melle, Andreassen, Agartz); the Norwegian Centre for Addiction Research (SERAF), Institute of Clinical Medicine, University of Oslo (Skjærvø); and the Division of Mental Health and Addiction, Oslo University Hospital (Melle, Andreassen), Oslo, Norway
| |
Collapse
|
56
|
Bowers H, Smith D, de la Salle S, Choueiry J, Impey D, Philippe T, Dort H, Millar A, Daigle M, Albert PR, Beaudoin A, Knott V. COMT polymorphism modulates the resting-state EEG alpha oscillatory response to acute nicotine in male non-smokers. GENES, BRAIN, AND BEHAVIOR 2015; 14:466-76. [PMID: 26096691 PMCID: PMC4514526 DOI: 10.1111/gbb.12226] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 06/15/2015] [Accepted: 06/15/2015] [Indexed: 11/28/2022]
Abstract
Performance improvements in cognitive tasks requiring executive functions are evident with nicotinic acetylcholine receptor (nAChR) agonists, and activation of the underlying neural circuitry supporting these cognitive effects is thought to involve dopamine neurotransmission. As individual difference in response to nicotine may be related to a functional polymorphism in the gene encoding catechol-O-methyltransferase (COMT), an enzyme that strongly influences cortical dopamine metabolism, this study examined the modulatory effects of the COMT Val158Met polymorphism on the neural response to acute nicotine as measured with resting-state electroencephalographic (EEG) oscillations. In a sample of 62 healthy non-smoking adult males, a single dose (6 mg) of nicotine gum administered in a randomized, double-blind, placebo-controlled design was shown to affect α oscillatory activity, increasing power of upper α oscillations in frontocentral regions of Met/Met homozygotes and in parietal/occipital regions of Val/Met heterozygotes. Peak α frequency was also found to be faster with nicotine (vs. placebo) treatment in Val/Met heterozygotes, who exhibited a slower α frequency compared to Val/Val homozygotes. The data tentatively suggest that interindividual differences in brain α oscillations and their response to nicotinic agonist treatment are influenced by genetic mechanisms involving COMT.
Collapse
Affiliation(s)
- H. Bowers
- Department of Psychology, University of Guelph, Guelph, ON, Canada
| | - D. Smith
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - S. de la Salle
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
| | - J. Choueiry
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - D. Impey
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
| | - T. Philippe
- University of Ottawa Institute of Mental Health Research, Royal Ottawa Mental Health Care Centre, Ottawa, ON, Canada
| | - H. Dort
- University of Ottawa Institute of Mental Health Research, Royal Ottawa Mental Health Care Centre, Ottawa, ON, Canada
| | - A. Millar
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
- Ottawa Hospital Research Institute, University of Ottawa, Ottawa, ON, Canada
| | - M. Daigle
- Ottawa Hospital Research Institute, University of Ottawa, Ottawa, ON, Canada
| | - P. R. Albert
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
- Ottawa Hospital Research Institute, University of Ottawa, Ottawa, ON, Canada
| | - A. Beaudoin
- University of Ottawa Institute of Mental Health Research, Royal Ottawa Mental Health Care Centre, Ottawa, ON, Canada
| | - V. Knott
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
- University of Ottawa Institute of Mental Health Research, Royal Ottawa Mental Health Care Centre, Ottawa, ON, Canada
| |
Collapse
|
57
|
Vreeker A, van Bergen AH, Kahn RS. Cognitive enhancing agents in schizophrenia and bipolar disorder. Eur Neuropsychopharmacol 2015; 25:969-1002. [PMID: 25957798 DOI: 10.1016/j.euroneuro.2015.04.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Accepted: 04/10/2015] [Indexed: 12/20/2022]
Abstract
Cognitive dysfunction is a core feature of schizophrenia and is also present in bipolar disorder (BD). Whereas decreased intelligence precedes the onset of psychosis in schizophrenia and remains relatively stable thereafter; high intelligence is a risk factor for bipolar illness but cognitive function decreases after onset of symptoms. While in schizophrenia, many studies have been conducted on the development of cognitive enhancing agents; in BD such studies are almost non-existent. This review focuses on the pharmacological agents with putative effects on cognition in both schizophrenia and bipolar illness; specifically agents targeting the dopaminergic, cholinergic and glutamatergic neurotransmitter pathways in schizophrenia and the cognitive effects of lithium, anticonvulsants and antipsychotics in BD. In the final analysis we conclude that cognitive enhancing agents have not yet been produced convincingly for schizophrenia and have hardly been studied in BD. Importantly, studies should focus on other phases of the illness. To be able to treat cognitive deficits effectively in schizophrenia, patients in the very early stages of the illness, or even before - in the ultra-high risk stages - should be targeted. In contrast, cognitive deficits occur later in BD, and therefore drugs should be tested in BD after the onset of illness. Hopefully, we will then find effective drugs for the incapacitating effects of cognitive deficits in these patients.
Collapse
Affiliation(s)
- Annabel Vreeker
- University Medical Center Utrecht, Department of Psychiatry, Brain Center Rudolf Magnus, The Netherlands
| | - Annet H van Bergen
- University Medical Center Utrecht, Department of Psychiatry, Brain Center Rudolf Magnus, The Netherlands
| | - René S Kahn
- University Medical Center Utrecht, Department of Psychiatry, Brain Center Rudolf Magnus, The Netherlands.
| |
Collapse
|
58
|
Hall FS, Der-Avakian A, Gould TJ, Markou A, Shoaib M, Young JW. Negative affective states and cognitive impairments in nicotine dependence. Neurosci Biobehav Rev 2015; 58:168-85. [PMID: 26054790 DOI: 10.1016/j.neubiorev.2015.06.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 02/13/2015] [Accepted: 06/03/2015] [Indexed: 10/23/2022]
Abstract
Smokers have substantial individual differences in quit success in response to current treatments for nicotine dependence. This observation may suggest that different underlying motivations for continued tobacco use across individuals and nicotine cessation may require different treatments in different individuals. Although most animal models of nicotine dependence emphasize the positive reinforcing effects of nicotine as the major motivational force behind nicotine use, smokers generally report that other consequences of nicotine use, including the ability of nicotine to alleviate negative affective states or cognitive impairments, as reasons for continued smoking. These states could result from nicotine withdrawal, but also may be associated with premorbid differences in affective and/or cognitive function. Effects of nicotine on cognition and affect may alleviate these impairments regardless of their premorbid or postmorbid origin (e.g., before or after the development of nicotine dependence). The ability of nicotine to alleviate these symptoms would thus negatively reinforce behavior, and thus maintain subsequent nicotine use, contributing to the initiation of smoking, the progression to dependence and relapse during quit attempts. The human and animal studies reviewed here support the idea that self-medication for pre-morbid and withdrawal-induced impairments may be more important factors in nicotine addiction and relapse than has been previously appreciated in preclinical research into nicotine dependence. Given the diverse beneficial effects of nicotine under these conditions, individuals might smoke for quite different reasons. This review suggests that inter-individual differences in the diverse effects of nicotine associated with self-medication and negative reinforcement are an important consideration in studies attempting to understand the causes of nicotine addiction, as well as in the development of effective, individualized nicotine cessation treatments.
Collapse
Affiliation(s)
- F Scott Hall
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, USA.
| | - Andre Der-Avakian
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
| | - Thomas J Gould
- Department of Psychology, Temple University, Philadelphia, PA, USA
| | - Athina Markou
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
| | - Mohammed Shoaib
- Institute of Neuroscience, Newcastle University, Newcastle, UK
| | - Jared W Young
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA; Research Service, VA San Diego Healthcare System, San Diego, CA, USA
| |
Collapse
|
59
|
Knott V, Impey D, Choueiry J, Smith D, de la Salle S, Saghir S, Smith M, Beaudry E, Ilivitsky V, Labelle A. An acute dose, randomized trial of the effects of CDP-Choline on Mismatch Negativity (MMN) in healthy volunteers stratified by deviance detection level. ACTA ACUST UNITED AC 2015. [DOI: 10.1186/s40810-014-0002-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
60
|
Ivanova SA, Toshchakova VA, Filipenko ML, Fedorenko OY, Boyarko EG, Boiko AS, Semke AV, Bokhan NA, Aftanas LI, Loonen AJM. Cytochrome P450 1A2 co-determines neuroleptic load and may diminish tardive dyskinesia by increased inducibility. World J Biol Psychiatry 2015; 16:200-5. [PMID: 25602162 DOI: 10.3109/15622975.2014.995222] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES The aim of this study was to investigate a possible association between tardive dyskinesia (TD) and CYP1A2 (*1F, -163C>А, rs762551) polymorphism in Russian psychiatric inpatients. METHODS TD was assessed cross-sectionally using the Abnormal Involuntary Movement Scale (AIMS). Orofacial and limb-truncal dyskinesia were assessed with AIMS 1-4 and 5-7, respectively. Standard protocols were applied for genotyping. Analysis of covariance (ANCOVA) was used to compare the mean AIMS scores for each of the genotypic classes. RESULTS A total of 319 Caucasian patients from West Siberia with schizophrenia and 117 healthy volunteers were investigated. No significant differences between the patients and the controls in genotype frequencies were found. Analysis of covariance (ANCOVA) with age, sex, duration of disease, chlorpromazine equivalent (CPZEQ) incorporated as covariates showed that limb-truncal, but not orofacial TD, is associated with CYP1A2 (-163C>, rs762551) polymorphism (F = 3.27, P = 0.039). Patients with the C/C genotype had a higher mean AIMS 5-7 score than those with the A/C or the A/A genotype. CONCLUSIONS Our results support the hypothesis that not only with clozapine, but also with other classical and atypical antipsychotics, smoking may decrease plasma levels; this is most extensively expressed in carriers of the CYP1A2*1F (-163C> A) polymorphism.
Collapse
Affiliation(s)
- Svetlana A Ivanova
- Mental Health Research Institute, Siberian Branch of RAMSc, Tomsk, Russian Federation
| | | | | | | | | | | | | | | | | | | |
Collapse
|
61
|
Hasan A, Falkai P, Wobrock T, Lieberman J, Glenthøj B, Gattaz WF, Thibaut F, Möller HJ. World Federation of Societies of Biological Psychiatry (WFSBP) Guidelines for Biological Treatment of Schizophrenia. Part 3: Update 2015 Management of special circumstances: Depression, Suicidality, substance use disorders and pregnancy and lactation. World J Biol Psychiatry 2015; 16:142-70. [PMID: 25822804 DOI: 10.3109/15622975.2015.1009163] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
These updated guidelines are based on the first edition of the World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for biological treatment of schizophrenia published in the years 2005 and 2006. For this 2015 revision, all available publications pertaining to the biological treatment of schizophrenia were reviewed systematically to allow for an evidence-based update. These guidelines provide evidence-based practice recommendations which are clinically and scientifically relevant. They are intended to be used by all physicians diagnosing and treating patients with schizophrenia. Based on the first version of these guidelines a systematic review, as well as a data extraction from national guidelines have been performed for this update. The identified literature was evaluated with respect to the strength of evidence for its efficacy and subsequently categorised into six levels of evidence (A-F) and five levels of recommendation (1-5). This third part of the updated guidelines covers the management of the following specific treatment circumstances: comorbid depression, suicidality, various comorbid substance use disorders (legal and illegal drugs), and pregnancy and lactation. These guidelines are primarily concerned with the biological treatment (including antipsychotic medication and other pharmacological treatment options) of patients with schizophrenia.
Collapse
Affiliation(s)
- Alkomiet Hasan
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University , Munich , Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
62
|
Smoking restores impaired LTD-like plasticity in schizophrenia: a transcranial direct current stimulation study. Neuropsychopharmacology 2015; 40:822-30. [PMID: 25308351 PMCID: PMC4330512 DOI: 10.1038/npp.2014.275] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Revised: 09/24/2014] [Accepted: 10/05/2014] [Indexed: 01/26/2023]
Abstract
Impaired neuroplastic responses following noninvasive brain stimulation have been reported repeatedly in schizophrenia patients. These findings have been associated with deficits in GABAergic, glutamatergic, and cholinergic neurotransmission. Although various neurophysiological studies have indicated a relationship between nicotine and neuroplasticity in healthy individuals, the present study is the first investigation into the impact of nicotine on LTD-like plasticity in patients with schizophrenia. Cortical excitability and cortical plasticity were explored in 30 schizophrenia patients (17 smoker, 13 nonsmoker) and 45 healthy controls (13 smoker, 32 nonsmoker) by using single-pulse transcranial magnetic stimulation (TMS) before and following cathodal transcranial direct current stimulation (tDCS) applied to the left primary motor cortex. Our analysis revealed abolished LTD-like plasticity in nonsmoking schizophrenia patients. However, these plasticity deficits were not present in smoking schizophrenia patients. In healthy controls, significant MEP reductions following cathodal tDCS were observed in nonsmoking individuals, but only trend-level reductions in smokers. In smoking schizophrenia patients, the severity of negative symptoms correlated positively with reduced neuroplasticity, whereas nonsmoking patients displayed the opposite effect. Taken together, the data of our study support the notion of an association between chronic smoking and the restitution of impaired LTD-like plasticity in schizophrenia patients. Although replication and further research are needed to better understand this relationship, our findings indicate that nicotine intake might stabilize the impaired inhibition-facilitation balance in the schizophrenic brain through a complex interaction between cortical plasticity, and GABAergic and cholinergic neurotransmission, and might explain the reduced prevalence of negative symptoms in this population.
Collapse
|
63
|
Picciotto MR, Lewis AS, van Schalkwyk GI, Mineur YS. Mood and anxiety regulation by nicotinic acetylcholine receptors: A potential pathway to modulate aggression and related behavioral states. Neuropharmacology 2015; 96:235-43. [PMID: 25582289 DOI: 10.1016/j.neuropharm.2014.12.028] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 12/02/2014] [Accepted: 12/16/2014] [Indexed: 12/22/2022]
Abstract
The co-morbidity between smoking and mood disorders is striking. Preclinical and clinical studies of nicotinic effects on mood, anxiety, aggression, and related behaviors, such as irritability and agitation, suggest that smokers may use the nicotine in tobacco products as an attempt to self-medicate symptoms of affective disorders. The role of nicotinic acetylcholine receptors (nAChRs) in circuits regulating mood and anxiety is beginning to be elucidated in animal models, but the mechanisms underlying the effects of nicotine on aggression-related behavioral states (ARBS) are still not understood. Clinical trials of nicotine or nicotinic medications for neurological and psychiatric disorders have often found effects of nicotinic medications on ARBS, but few trials have studied these outcomes systematically. Similarly, the increase in ARBS resulting from smoking cessation can be resolved by nicotinic agents, but the effects of nicotinic medications on these types of mental states and behaviors in non-smokers are less well understood. Here we review the literature on the role of nAChRs in regulating mood and anxiety, and subsequently on the closely related construct of ARBS. We suggest avenues for future study to identify how nAChRs and nicotinic agents may play a role in these clinically important areas. This article is part of the Special Issue entitled 'The Nicotinic Acetylcholine Receptor: From Molecular Biology to Cognition'.
Collapse
Affiliation(s)
| | - Alan S Lewis
- Department of Psychiatry, Yale University, New Haven, CT 06508, USA
| | | | - Yann S Mineur
- Department of Psychiatry, Yale University, New Haven, CT 06508, USA
| |
Collapse
|
64
|
Knott V, Impey D, Philippe T, Smith D, Choueiry J, de la Salle S, Dort H. Modulation of auditory deviance detection by acute nicotine is baseline and deviant dependent in healthy nonsmokers: a mismatch negativity study. Hum Psychopharmacol 2014; 29:446-58. [PMID: 25196041 DOI: 10.1002/hup.2418] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 03/19/2014] [Accepted: 05/19/2014] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Cognitive enhancement resulting from nicotinic acetylcholine receptor stimulation may be evidenced by increased efficiency of the auditory-frontal cortex network of auditory discrimination, which is impaired in schizophrenia, a cognitive disorder associated with excessive tobacco use. Investigating automatic (preattentive) detection of acoustic change with the mismatch negativity (MMN) brain event-related potential in response to nicotine in individuals with varying baseline levels of auditory discrimination may provide useful insight into the cholinergic regulation of this neural network and its potential amelioration with novel nicotinic agents. METHODS Sixty healthy, non-smoking male volunteers were presented with an 'optimal' multi-feature MMN paradigm in a randomized, placebo controlled double-blind design with 6 mg of nicotine gum. RESULTS Participants with low, medium, and high baseline amplitudes responded differently to nicotine (vs. placebo), and nicotine response was feature specific. Whereas MMN in individuals with high amplitudes was diminished by nicotine, MMN increased in those with low amplitudes. Nicotine effects were not shown in medium amplitude participants. CONCLUSIONS These findings provide preliminary support for the role of nicotinic neurotransmission in sensory memory processing of auditory change and suggest that nicotinic receptor modulation can both enhance and diminish change detection, depending on baseline MMN and its eliciting stimulus feature.
Collapse
Affiliation(s)
- Verner Knott
- University of Ottawa Institute of Mental Health Research, Ottawa, Ontario, Canada; School of Psychology, University of Ottawa, Ottawa, Ontario, Canada; Neuroscience Program, Department of Cellular and Molecular Medicine, University of Ottawa, Ontario, Canada
| | | | | | | | | | | | | |
Collapse
|
65
|
Jasinska AJ, Zorick T, Brody AL, Stein EA. Dual role of nicotine in addiction and cognition: a review of neuroimaging studies in humans. Neuropharmacology 2014; 84:111-22. [PMID: 23474015 PMCID: PMC3710300 DOI: 10.1016/j.neuropharm.2013.02.015] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 12/28/2012] [Accepted: 02/19/2013] [Indexed: 12/11/2022]
Abstract
Substantial evidence demonstrates both nicotine's addiction liability and its cognition-enhancing effects. However, the neurobiological mechanisms underlying nicotine's impact on brain function and behavior remain incompletely understood. Elucidation of these mechanisms is of high clinical importance and may lead to improved therapeutics for smoking cessation as well as for a number of cognitive disorders such as schizophrenia. Neuroimaging techniques such as positron emission tomography (PET), single photon emission computed tomography (SPECT), and functional magnetic resonance imaging (fMRI), which make it possible to study the actions of nicotine in the human brain in vivo, play an increasingly important role in identifying these dual mechanisms of action. In this review, we summarize the current state of knowledge and discuss outstanding questions and future directions in human neuroimaging research on nicotine and tobacco. This research spans from receptor-level PET and SPECT studies demonstrating nicotine occupancy at nicotinic acetylcholine receptors (nAChRs) and upregulation of nAChRs induced by chronic smoking; through nicotine's interactions with the mesocorticolimbic dopamine system believed to mediate nicotine's reinforcing effects leading to dependence; to functional activity and connectivity fMRI studies documenting nicotine's complex behavioral and cognitive effects manifest by its actions on large-scale brain networks engaged both during task performance and at rest. This article is part of the Special Issue Section entitled 'Neuroimaging in Neuropharmacology'.
Collapse
Affiliation(s)
- Agnes J Jasinska
- National Institute on Drug Abuse, Intramural Research Program, 251 Bayview Blvd, Baltimore, MD 21224, United States.
| | - Todd Zorick
- University of California at Los Angeles, Department of Psychiatry, 300 UCLA Medical Plaza, Los Angeles, CA 90095, United States; VA Greater Los Angeles Healthcare System, United States
| | - Arthur L Brody
- University of California at Los Angeles, Department of Psychiatry, 300 UCLA Medical Plaza, Los Angeles, CA 90095, United States; VA Greater Los Angeles Healthcare System, United States.
| | - Elliot A Stein
- National Institute on Drug Abuse, Intramural Research Program, 251 Bayview Blvd, Baltimore, MD 21224, United States.
| |
Collapse
|
66
|
Higley MJ, Picciotto MR. Neuromodulation by acetylcholine: examples from schizophrenia and depression. Curr Opin Neurobiol 2014; 29:88-95. [PMID: 24983212 DOI: 10.1016/j.conb.2014.06.004] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 06/02/2014] [Accepted: 06/05/2014] [Indexed: 02/06/2023]
Abstract
The contribution of acetylcholine to psychiatric illnesses remains an area of active research. For example, increased understanding of mechanisms underlying cholinergic modulation of cortical function has provided insight into attentional dysfunction in schizophrenia. Acetylcholine normally enhances cortical sensitivity to external stimuli and decreases corticocortical communication, increasing focused attention; however, increases in ACh signaling can lead to symptoms related to anxiety and depression. For example, while stress-induced ACh release can result in adaptive responses to environmental stimuli, chronic elevations in cholinergic signaling may produce maladaptive behaviors. Here, we review several innovations in human imaging, molecular genetics and physiological control of circuits that have begun to identify mechanisms linking altered cholinergic neuromodulation to schizophrenia and depression.
Collapse
Affiliation(s)
- Michael J Higley
- Dept. of Neurobiology, Yale University School of Medicine, New Haven, CT 06511, United States; Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT 06511, United States.
| | - Marina R Picciotto
- Dept. of Neurobiology, Yale University School of Medicine, New Haven, CT 06511, United States; Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT 06511, United States; Dept. of Psychiatry, Yale University School of Medicine, New Haven, CT 06511, United States.
| |
Collapse
|
67
|
Grizzell JA, Echeverria V. New Insights into the Mechanisms of Action of Cotinine and its Distinctive Effects from Nicotine. Neurochem Res 2014; 40:2032-46. [PMID: 24970109 DOI: 10.1007/s11064-014-1359-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 06/10/2014] [Indexed: 12/20/2022]
Abstract
Tobacco consumption is far higher among a number of psychiatric and neurological diseases, supporting the notion that some component(s) of tobacco may underlie the oft-reported reduction in associated symptoms during tobacco use. Popular dogma holds that this component is nicotine. However, increasing evidence support theories that cotinine, the main metabolite of nicotine, may underlie at least some of nicotine's actions in the nervous system, apart from its adverse cardiovascular and habit forming effects. Though similarities exist, disparate and even antagonizing actions between cotinine and nicotine have been described both in terms of behavior and physiology, underscoring the need to further characterize this potentially therapeutic compound. Cotinine has been shown to be psychoactive in humans and animals, facilitating memory, cognition, executive function, and emotional responding. Furthermore, recent research shows that cotinine acts as an antidepressant and reduces cognitive-impairment associated with disease and stress-induced dysfunction. Despite these promising findings, continued focus on this potentially safe alternative to tobacco and nicotine use is lacking. Here, we review the effects of cotinine, including comparisons with nicotine, and discuss potential mechanisms of cotinine-specific actions in the central nervous system which are, to date, still being elucidated.
Collapse
Affiliation(s)
- J Alex Grizzell
- Department of Psychiatry and Behavioral Neurosciences, Morsani College of Medicine, University of South Florida, Tampa, FL, 33611, USA.,Department of Research and Development, Bay Pines VA Healthcare System, 10,000 Bay Pines Blvd., Bldg. 23, Rm. 123, Bay Pines, FL, 33744, USA
| | - Valentina Echeverria
- Department of Research and Development, Bay Pines VA Healthcare System, 10,000 Bay Pines Blvd., Bldg. 23, Rm. 123, Bay Pines, FL, 33744, USA. .,Universidad Autónoma de Chile, Carlos Antúnez 1920, Providencia, Santiago, Chile. .,Department of Molecular Medicine, University of South Florida, Tampa, FL, 33647, USA.
| |
Collapse
|
68
|
Uslu G, Savci V, Buyukuysal LR, Goktalay G. CDP-choline attenuates scopolamine induced disruption of prepulse inhibition in rats: involvement of central nicotinic mechanism. Neurosci Lett 2014; 569:153-7. [PMID: 24708927 DOI: 10.1016/j.neulet.2014.03.070] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 03/24/2014] [Accepted: 03/27/2014] [Indexed: 12/27/2022]
Abstract
It has been shown that cholinergic system plays an important role in schizophrenia-associated cognitive deficits, therefore cholinergic drugs are novel targets for the treatment of cognitive deficits seen in schizophrenia. We aimed to test the effects of CDP-choline on sensorimotor gating functioning, which is an important function for the integration of sensory and cognitive information processing and the execution of appropriate motor responses. In this study, prepulse inhibition (PPI) of the acoustic startle reflex was used to test the sensorimotor gating functioning, and the effects of CDP-choline on scopolamine induced PPI disruption were evaluated in rats. Furthermore, the contribution of the cholinergic mechanism in these effects was determined. CDP-choline (75, 250, 500mg/kg) by itself had no effect on the PPI in naïve animals. Scopolamine (0.4mg/kg; s.c.) significantly decreased the PPI levels and intraperitoneal administration of CDP-choline (250mg/kg) attenuated the effects of scopolamine. A non-specific nicotinic receptor antagonist, mecamylamine and an alpha 7 nicotinic receptor (α7-nAChR) antagonist, methyllycaconitine were used to investigate the mechanism underlying the effects of CDP-choline. Mecamylamine (3mg/kg; s.c.), and methyllycaconitine (10μg; i.c.v.) completely blocked the reversal effects of CDP-choline on scopolamine induced disruption of PPI. These results demonstrate that exogenous administration of CDP-choline attenuates scopolamine induced PPI disruption and show that the activation of central α7-nAChR may play a critical role in this effect.
Collapse
Affiliation(s)
- Gulsah Uslu
- Department of Medical Pharmacology, Uludag University Faculty of Medicine, Bursa, Turkey
| | - Vahide Savci
- Department of Medical Pharmacology, Uludag University Faculty of Medicine, Bursa, Turkey
| | - Levent R Buyukuysal
- Department of Medical Pharmacology, Uludag University Faculty of Medicine, Bursa, Turkey
| | - Gokhan Goktalay
- Department of Medical Pharmacology, Uludag University Faculty of Medicine, Bursa, Turkey.
| |
Collapse
|
69
|
Romano E, De Angelis F, Ulbrich L, De Jaco A, Fuso A, Laviola G. Nicotine exposure during adolescence: cognitive performance and brain gene expression in adult heterozygous reeler mice. Psychopharmacology (Berl) 2014; 231:1775-87. [PMID: 24337025 DOI: 10.1007/s00213-013-3388-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 11/30/2013] [Indexed: 12/11/2022]
Abstract
RATIONALE We have recently reported nicotine-induced stimulation of reelin and glutamic acid decarboxylase 67 (GAD67) mRNA expression levels in the brain of heterozygous reeler mice (HRM), a putative animal model for the study of symptoms relevant to major behavioral disorders. OBJECTIVES We aimed to evaluate long-term behavioral effects and brain molecular changes as a result of adaptations to nicotine exposure in the developing HRM males. METHODS Adolescent mice (pnd 37-42) were exposed to oral nicotine (10 mg/l) in a 6-day free-choice drinking schedule. As expected, no differences in total nicotine intake between WT (wild-type) mice and HRM were found. RESULTS Long-term behavioral effects and brain molecular changes, as a consequence of nicotine exposure during adolescence, were only evidenced in HRM. Indeed, HRM perseverative exploratory behavior and poor cognitive performance were modulated to WT levels by subchronic exposure to nicotine during development. Furthermore, the expected reduction in the expression of mRNA of reelin and GAD67 in behaviorally relevant brain areas of HRM appeared persistently restored by nicotine. For brain-derived neurotrophic factor (BDNF) mRNA expression, no genotype-dependent changes appeared. However, expression levels were increased by previous nicotine in brains from both genotypes. The mRNA encoding for nicotine receptor subunits (α7, β2 and α4) did not differ between genotypes and as a result of previous nicotine exposure. CONCLUSION These findings support the hypothesis of pre-existing vulnerability (based on haploinsufficiency of reelin) to brain and behavioral disorders and regulative short- and long-term effects associated with nicotine modulation.
Collapse
Affiliation(s)
- Emilia Romano
- Section of Behavioural Neuroscience, Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | | | | | | | | | | |
Collapse
|
70
|
Bloem B, Poorthuis RB, Mansvelder HD. Cholinergic modulation of the medial prefrontal cortex: the role of nicotinic receptors in attention and regulation of neuronal activity. Front Neural Circuits 2014; 8:17. [PMID: 24653678 PMCID: PMC3949318 DOI: 10.3389/fncir.2014.00017] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 02/20/2014] [Indexed: 11/27/2022] Open
Abstract
Acetylcholine (ACh) release in the medial prefrontal cortex (mPFC) is crucial for normal cognitive performance. Despite the fact that many have studied how ACh affects neuronal processing in the mPFC and thereby influences attention behavior, there is still a lot unknown about how this occurs. Here we will review the evidence that cholinergic modulation of the mPFC plays a role in attention and we will summarize the current knowledge about the role between ACh receptors (AChRs) and behavior and how ACh receptor activation changes processing in the cortical microcircuitry. Recent evidence implicates fast phasic release of ACh in cue detection and attention. This review will focus mainly on the fast ionotropic nicotinic receptors and less on the metabotropic muscarinic receptors. Finally, we will review limitations of the existing studies and address how innovative technologies might push the field forward in order to gain understanding into the relation between ACh, neuronal activity and behavior.
Collapse
Affiliation(s)
- Bernard Bloem
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, Vrije UniversiteitAmsterdam, Netherlands
- McGovern Institute for Brain Research, Massachusetts Institute of TechnologyCambridge, MA, USA
| | | | - Huibert D. Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, Vrije UniversiteitAmsterdam, Netherlands
| |
Collapse
|
71
|
Roh S, Hoeppner SS, Schoenfeld D, Fullerton CA, Stoeckel LE, Evins AE. Acute effects of mecamylamine and varenicline on cognitive performance in non-smokers with and without schizophrenia. Psychopharmacology (Berl) 2014; 231:765-75. [PMID: 24114425 PMCID: PMC4060791 DOI: 10.1007/s00213-013-3286-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 09/12/2013] [Indexed: 01/10/2023]
Abstract
RATIONALE Nicotinic acetylcholine receptors (nAChRs) have been implicated in the pathophysiology of cognitive deficits in the domains of attention and memory in schizophrenia. While nicotinic agonists and antagonists have been proposed as smoking cessation aids, few comparisons have been made of these agents on cognitive performance in individuals with schizophrenia. OBJECTIVES This study investigated the acute effects of a nAChR antagonist, mecamylamine, and partial agonist, varenicline, on cognitive function in non-smokers with and without schizophrenia. METHODS Single oral doses of mecamylamine 10 mg, varenicline 1 mg, and placebo were administered 1 week apart in random order to adults with schizophrenia (n = 30) and to healthy volunteers (n = 41) in a double-blind, crossover design. The primary outcome of interest was sustained attention as assessed with hit reaction time variability (HRT-SD) on the identical pairs continuous performance test (CPT-IP). RESULTS Mecamylamine worsened performance on CPT-IP HRT-SD, a measure of attention, compared to varenicline in both groups. Performance on mecamylamine was worse than performance on both placebo and varenicline on several additional measures of attention, including CPT-IP hit reaction time (HRT) and random errors at various levels of task difficulty. There was a treatment by diagnosis interaction, such that mecamylamine worsened performance on CPT-IP 2-digit HRT, 3-digit random errors, and 4-digit hit rate compared to placebo and varenicline in participants with schizophrenia; effects not observed in controls. CONCLUSIONS These findings support a role for nAChRs in attention and suggest that those with schizophrenia may be particularly sensitive to nAChR blockade.
Collapse
Affiliation(s)
- Sungwon Roh
- Center for Addiction Medicine, Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, 60 Staniford Street, Boston, MA, 02114, USA
| | | | | | | | | | | |
Collapse
|
72
|
Quisenaerts C, Morrens M, Hulstijn W, de Bruijn E, Timmers M, Streffer J, De la Asuncion J, Dumont G, Sabbe B. The nicotinergic receptor as a target for cognitive enhancement in schizophrenia: barking up the wrong tree? Psychopharmacology (Berl) 2014; 231:543-50. [PMID: 24022237 DOI: 10.1007/s00213-013-3264-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/22/2013] [Indexed: 12/29/2022]
Abstract
RATIONALE Cognitive symptoms have increasingly been recognized as an important target in the development of future treatment strategies in schizophrenia. The nicotinergic neurotransmission system has been suggested as a potentially interesting treatment target for these cognitive deficits. However, previous research yielded conflicting results, which may be explained by several methodological limitations, such as the failure to include both a group of smoking and non-smoking schizophrenic patients, the use of only a single nicotine dose, and the inclusion of a very limited cognitive battery. OBJECTIVES The present study aims at investigating the cognitive effects of nicotine in schizophrenia while addressing these methodological issues. METHODS In a double-blind placebo-controlled randomized crossover design, cognitive effects are assessed in smoking (n =16) and non-smoking (n =16) schizophrenic patients after receiving active (1 or 2 mg) or placebo oromucosal nicotine spray. RESULTS A modest improving effect of nicotine on attention in the smoking but not the non-smoking group was found. No enhancing effects were found on measures of visual memory, working memory, processing speed, psychomotor speed, or social cognitive functioning in either patient group. CONCLUSIONS These findings suggest that the nicotinic receptor only has limited value as a cognitive treatment target in schizophrenia.
Collapse
|
73
|
Kayir H, Semenova S, Markou A. Baseline impulsive choice predicts the effects of nicotine and nicotine withdrawal on impulsivity in rats. Prog Neuropsychopharmacol Biol Psychiatry 2014; 48:6-13. [PMID: 24060391 PMCID: PMC3858513 DOI: 10.1016/j.pnpbp.2013.09.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 08/26/2013] [Accepted: 09/12/2013] [Indexed: 10/26/2022]
Abstract
Impulsive choice, a form of impulsivity, is associated with tobacco smoking in humans. Trait impulsivity may be a vulnerability factor for smoking, or smoking may lead to impulsive behaviors. We investigated the effects of 14-day nicotine exposure (6.32mg/kg/day base, subcutaneous minipumps) and spontaneous nicotine withdrawal on impulsive choice in low impulsive (LI) and high impulsive (HI) rats. Impulsive choice was measured in the delayed reward task in which rats choose between a small immediate reward and a large delayed reward. HI and LI rats were selected from the highest and lowest quartiles of the group before exposure to nicotine. In non-selected rats, nicotine or nicotine withdrawal had no effect on impulsive choice. In LI rats, chronic nicotine exposure decreased preference for the large reward with larger effects at longer delays, indicating increased impulsive choice. Impulsive choices for the smaller immediate rewards continued to increase during nicotine withdrawal in LI rats. In HI rats, nicotine exposure and nicotine withdrawal had no effect on impulsive choice, although there was a tendency for decreased preference for the large reward at short delays. These results indicate that nicotine- and nicotine withdrawal-induced increases in impulsive choice depend on trait impulsivity with more pronounced increases in impulsive choice in LI compared to HI subjects. Increased impulsivity during nicotine exposure may strengthen the addictive properties of nicotine and contribute to compulsive nicotine use.
Collapse
Affiliation(s)
- Hakan Kayir
- Department of Psychiatry, School of Medicine, University of California San Diego, La Jolla, CA, USA,Department of Medical Pharmacology, Psychopharmacology Research Unit, Gulhane Military Medical Academy, Ankara, Turkey
| | - Svetlana Semenova
- Department of Psychiatry, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Athina Markou
- Department of Psychiatry, School of Medicine, University of California San Diego, La Jolla, CA, USA,Corresponding author: Athina Markou, Ph.D., Department of Psychiatry, Mail Code 0603, School of Medicine, University of California San Diego, 9500 Gilman Drive, La Jolla, California 92093-0603, USA; tel: (858) 534-1572; fax: (858) 534-9917;
| |
Collapse
|
74
|
Boyer L, Richieri R, Dassa D, Boucekine M, Fernandez J, Vaillant F, Padovani R, Auquier P, Lancon C. Association of metabolic syndrome and inflammation with neurocognition in patients with schizophrenia. Psychiatry Res 2013; 210:381-6. [PMID: 23850204 DOI: 10.1016/j.psychres.2013.06.020] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 05/13/2013] [Accepted: 06/14/2013] [Indexed: 12/17/2022]
Abstract
The aim of this study is to assess the relationships of metabolic syndrome (MetS) and inflammation with neurocognition in schizophrenia. In this cross-sectional study, we included patients with diagnosis of schizophrenia according to the DSM-IV-TR criteria. We collected socio-demographic information, clinical characteristics, anthropometric measurements, blood tests, and neurocognition measures. A multivariate analysis using multiple linear regressions was performed to determine variables that are potentially associated with neurocognition. The analyses were repeated using MetS as a dichotomised variable (< and ≥ 3 MetS criteria), a continuous variable (number of MetS criteria present), and for each component of MetS. One hundred and sixty-eight outpatients participated in our study. The prevalence of MetS was 27.4%. An association was found between the number of MetS criteria present and cognitive impairment. Among the different components of MetS, hypertriglycerides and abdominal obesity were the only factors associated with cognitive impairment. Other factors, such as smoking and alcohol dependence or abuse, also revealed a significant relationship, whereas inflammation was not associated with cognitive impairment. In conclusion, our findings suggest that MetS, alcohol use and non-smoking status are associated with cognitive impairment. These findings may support complementary therapeutic approaches in cognitive remediation that lessen the severity of cognitive impairment in schizophrenia.
Collapse
Affiliation(s)
- Laurent Boyer
- Aix-Marseille University, EA 3279 - Public Health, Chronic Diseases and Quality of Life - Research Unit, 13005 Marseille, France.
| | | | | | | | | | | | | | | | | |
Collapse
|
75
|
Boggs DL, Ranganathan M, Sewell RA, Madonick S, D'Souza DC. Pilot study of intravenous nicotine effects on cognitive performance in schizophrenia. Schizophr Res 2013; 150:323-4. [PMID: 23953216 DOI: 10.1016/j.schres.2013.07.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 07/15/2013] [Accepted: 07/24/2013] [Indexed: 01/03/2023]
Affiliation(s)
- Douglas L Boggs
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA; Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, New Haven, CT, USA.
| | | | | | | | | |
Collapse
|
76
|
Hahn B, Harvey AN, Concheiro-Guisan M, Huestis MA, Holcomb HH, Gold JM. A test of the cognitive self-medication hypothesis of tobacco smoking in schizophrenia. Biol Psychiatry 2013; 74:436-43. [PMID: 23660272 PMCID: PMC3755590 DOI: 10.1016/j.biopsych.2013.03.017] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Revised: 02/22/2013] [Accepted: 03/15/2013] [Indexed: 12/15/2022]
Abstract
BACKGROUND Heavier tobacco smoking among people with schizophrenia (SCZ) has been suggested to reflect self-medication of cognitive deficits. The idea that cognitive-enhancing effects of nicotine are a primary motivator of tobacco consumption in SCZ and that abstinence would deprive SCZ of such beneficial effects might explain hesitation among providers to pursue smoking cessation in SCZ. This study tested predictions of the cognitive self-medication hypothesis. METHODS In three counterbalanced sessions, 17 SCZ and 17 healthy control subjects (HCS), all smokers, were tested under ad libitum smoking or 3.5 hours after abstaining and receiving a nicotine (14 mg/24 hours) or placebo patch. RESULTS Attention task performance was improved by transdermal nicotine relative to placebo, with intermediate performance by ad libitum smoking. These effects were of similar size in SCZ and HCS and did not reflect remediation of functions disproportionately impaired in SCZ. Although more SCZ reported that the need to concentrate influenced their smoking, this was not reflected by the actual behavior of these patients. Self-reported ability to concentrate changed with nicotine status in HCS but not SCZ, suggesting insensitivity of SCZ to nicotine-derived performance benefits. Nicotine plasma concentrations after ad libitum smoking were not associated with performance benefits but instead with the propensity to experience nicotine withdrawal upon abstinence. This association was seen selectively in SCZ, suggesting a possible reason for heavier smoking. CONCLUSIONS These findings suggest that subjective or objective attentional benefits are unlikely the primary driving force of tobacco consumption in SCZ and should not discourage providers from supporting quit attempts.
Collapse
Affiliation(s)
- Britta Hahn
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD 21228, USA.
| | | | | | | | | | | |
Collapse
|
77
|
Roth M, Hong LE, McMahon RP, Fuller RL. Comparison of the effectiveness of Conners' CPT and the CPT-identical pairs at distinguishing between smokers and nonsmokers with schizophrenia. Schizophr Res 2013; 148:29-33. [PMID: 23791390 PMCID: PMC3732498 DOI: 10.1016/j.schres.2013.06.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 05/24/2013] [Accepted: 06/02/2013] [Indexed: 12/31/2022]
Abstract
Sustained attention deficits and high rates of smoking are often observed in patients with schizophrenia. This has led to the hypothesis that patients may smoke as an attempt to ameliorate cognitive deficits related to abnormal nicotinic structure and function. Continuous performance tasks (CPT) are often used to index sustained attention deficits in patients with schizophrenia, however, there are important differences between tasks that may impact performance in smokers and nonsmokers with schizophrenia differently. The Conners' CPT (C-CPT) has a high signal-to-noise ratio and is commonly used to assess impulsivity. The CPT-Identical Pairs (CPT-IP) has a low signal-to-noise ratio and is commonly used to assess negative symptoms in patients with schizophrenia. We sought to determine whether there were differences of sustained attention between patient smokers vs. nonsmokers, and if one CPT would provide a better separation of sustained attention between groups. Results revealed that both instruments detect more impaired sustained attention deficits in patient smokers compared to nonsmokers. Patient smokers performed significantly worse on the majority of the CPT-IP composite scores compared to the C-CPT composite scores. These results do not support the self-medication theory, as patient smokers performed worse than patient nonsmokers. Researchers studying sustained attention in schizophrenia may wish to consider the CPT-IP over the C-CPT, as well as control for smoking status.
Collapse
Affiliation(s)
- Michelle Roth
- Department of Psychology, The Catholic University of America, 620 Michigan Avenue, NE, Washington, DC 20064 USA.
| | - L. Elliot Hong
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, Maryland, 21228 USA,
| | - Robert P. McMahon
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, PO Box 21247, Baltimore, Maryland, 21228 USA,
| | - Rebecca L. Fuller
- Department of Psychology, The Catholic University of America, 620 Michigan Avenue, NE, Washington, DC, 20064 USA,
| |
Collapse
|
78
|
Young JW, Geyer MA. Evaluating the role of the alpha-7 nicotinic acetylcholine receptor in the pathophysiology and treatment of schizophrenia. Biochem Pharmacol 2013; 86:1122-32. [PMID: 23856289 DOI: 10.1016/j.bcp.2013.06.031] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 06/27/2013] [Accepted: 06/28/2013] [Indexed: 12/16/2022]
Abstract
The group of schizophrenia disorders affects approximately 1% of the population and has both genetic and environmental etiologies. Sufferers report various behavioral abnormalities including hallucinations and delusions (positive symptoms), reduced joy and amotivation (negative symptoms), plus inattention and poor learning (cognitive deficits). Despite the heterogeneous symptoms experienced, most patients smoke. The self-medication hypothesis posits that patients smoke to alleviate symptoms, consistent with evidence for nicotine-induced enhancement of cognition. While nicotine acts on multiple nicotinic acetylcholine receptors (nAChRs), the primary target of research is often the homomeric α7 nAChR. Given genetic linkages between schizophrenia and this receptor, its association with P50 sensory gating deficits, and its reduced expression in post-mortem brains, many have attempted to develop α7 nAChR ligands for treating schizophrenia. Recent evidence that ligands can be orthosteric agonists or positive allosteric modulators (PAMs) has revitalized the hope for treatment discovery. Herein, we present evidence regarding: (1) pathophysiological alterations of α7 nAChRs that might occur in patients; (2) mechanistic evidence for the normal action of α7 nAChRs; (3) preclinical studies using α7 nAChR orthosteric agonists and type I/II PAMs; and (4) where successful translational testing has occurred for particular compounds, detailing what is still required. We report that the accumulating evidence is positive, but that greater work is required using positron emission tomography to understand current alterations in α7 nAChR expression and their relationship to symptoms. Finally, cross-species behavioral tasks should be used more regularly to determine the predictive efficacy of treatments.
Collapse
Affiliation(s)
- Jared W Young
- Department of Psychiatry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0804, United States; Research Service, San Diego Veteran's Affairs Hospital, 3350 La Jolla Drive, San Diego, CA 92037, United States.
| | | |
Collapse
|
79
|
Acheson DT, Twamley EW, Young JW. Reward learning as a potential target for pharmacological augmentation of cognitive remediation for schizophrenia: a roadmap for preclinical development. Front Neurosci 2013; 7:103. [PMID: 23785309 PMCID: PMC3684768 DOI: 10.3389/fnins.2013.00103] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 05/23/2013] [Indexed: 12/14/2022] Open
Abstract
Rationale: Impaired cognitive abilities are a key characteristic of schizophrenia. Although currently approved pharmacological treatments have demonstrated efficacy for positive symptoms, to date no pharmacological treatments successfully reverse cognitive dysfunction in these patients. Cognitively-based interventions such as cognitive remediation (CR) and other psychosocial interventions however, may improve some of the cognitive and functional deficits of schizophrenia. Given that these treatments are time-consuming and labor-intensive, maximizing their effectiveness is a priority. Augmenting psychosocial interventions with pharmacological treatments may be a viable strategy for reducing the impact of cognitive deficits in patients with schizophrenia. Objective: We propose a strategy to develop pharmacological treatments that can enhance the reward-related learning processes underlying successful skill-learning in psychosocial interventions. Specifically, we review clinical and preclinical evidence and paradigms that can be utilized to develop these pharmacological augmentation strategies. Prototypes for this approach include dopamine D1 receptor and α7 nicotinic acetylcholine receptor agonists as attractive targets to specifically enhance reward-related learning during CR. Conclusion: The approach outlined here could be used broadly to develop pharmacological augmentation strategies across a number of cognitive domains underlying successful psychosocial treatment.
Collapse
Affiliation(s)
- Dean T Acheson
- Department of Psychiatry, University of California San Diego La Jolla, San Diego, CA, USA ; Research Service, San Diego Veteran's Affairs Hospital San Diego, CA, USA
| | | | | |
Collapse
|
80
|
Zugno AI, Fraga DB, De Luca RD, Ghedim FV, Deroza PF, Cipriano AL, Oliveira MB, Heylmann ASA, Budni J, Souza RP, Quevedo J. Chronic exposure to cigarette smoke during gestation results in altered cholinesterase enzyme activity and behavioral deficits in adult rat offspring: potential relevance to schizophrenia. J Psychiatr Res 2013; 47:740-6. [PMID: 23472836 DOI: 10.1016/j.jpsychires.2013.02.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 02/06/2013] [Accepted: 02/07/2013] [Indexed: 01/18/2023]
Abstract
Prenatal cigarette smoke exposure (PCSE) has been associated with physiological and developmental changes that may be related to an increased risk for childhood and adult neuropsychiatric diseases. The present study investigated locomotor activity and cholinesterase enzyme activity in rats, following PCSE and/or ketamine treatment in adulthood. Pregnant female Wistar rats were exposed to 12 commercially filtered cigarettes per day for a period of 28 days. We evaluated motor activity and cholinesterase activity in the brain and serum of adult male offspring that were administered acute subanesthetic doses of ketamine (5, 15 and 25 mg/kg), which serves as an animal model of schizophrenia. To determine locomotor activity, we used the open field test. Cholinesterase activity was assessed by hydrolysis monitored spectrophotometrically. Our results show that both PCSE and ketamine treatment in the adult offspring induced increase of locomotor activity. Additionally, it was observed increase of acetylcholinesterase and butyrylcholinesterase activity in the brain and serum, respectively. We demonstrated that animals exposed to cigarettes in the prenatal period had increased the risk for psychotic symptoms in adulthood. This also occurs in a dose-dependent manner. These changes provoke molecular events that are not completely understood and may result in abnormal behavioral responses found in neuropsychiatric disorders, such as schizophrenia.
Collapse
Affiliation(s)
- Alexandra I Zugno
- Laboratório de Neurociências, Instituto Nacional de Ciência e Tecnologia Translacional em Medicina (INCT-TM), and Núcleo de Excelência em Neurociências Aplicadas de Santa Catarina (NENASC), Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, 88806-000 Criciúma, SC, Brazil.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
81
|
Ng E, McGirr A, Wong AHC, Roder JC. Using rodents to model schizophrenia and substance use comorbidity. Neurosci Biobehav Rev 2013; 37:896-910. [PMID: 23567519 DOI: 10.1016/j.neubiorev.2013.03.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 03/28/2013] [Accepted: 03/29/2013] [Indexed: 12/13/2022]
Abstract
Schizophrenia and substance use disorders (SUD) often occur together, yet it is unclear why this is the case or how best to manage dual diagnosis. Rodent models are well suited to study how genes and environment interact to impact neurodevelopment, brain function and behaviors relevant to dual diagnosis. Indeed a variety of rodent models for schizophrenia display behavioral and physiological features relevant to SUD including: neurodevelopmental models, models of a rare variant (Disc1), to models of common variants (neurexin, dysbindin and neuregulin), and models of various gene-drug interactions. Thus it may be worthwhile to probe models of schizophrenia for insights relevant to SUD and dual diagnosis. However, future studies on dual diagnosis should involve characterization beyond measuring locomotor responses to self-administration tasks, include drug classes other than psychostimulants, and dissect the neuroadaptations that underlie risk for dual diagnosis.
Collapse
Affiliation(s)
- Enoch Ng
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Room 860, Toronto, Ontario M5G 1X5, Canada.
| | | | | | | |
Collapse
|
82
|
Giessing C, Thiel CM, Alexander-Bloch AF, Patel AX, Bullmore ET. Human brain functional network changes associated with enhanced and impaired attentional task performance. J Neurosci 2013; 33:5903-14. [PMID: 23554472 PMCID: PMC6618923 DOI: 10.1523/jneurosci.4854-12.2013] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 01/08/2013] [Accepted: 02/03/2013] [Indexed: 12/26/2022] Open
Abstract
How is the cognitive performance of the human brain related to its topological and spatial organization as a complex network embedded in anatomical space? To address this question, we used nicotine replacement and duration of attentionally demanding task performance (time-on-task), as experimental factors expected, respectively, to enhance and impair cognitive function. We measured resting-state fMRI data, performance and brain activation on a go/no-go task demanding sustained attention, and subjective fatigue in n = 18 healthy, briefly abstinent, cigarette smokers scanned repeatedly in a placebo-controlled, crossover design. We tested the main effects of drug (placebo vs Nicorette gum) and time-on-task on behavioral performance and brain functional network metrics measured in binary graphs of 477 regional nodes (efficiency, measure of integrative topology; clustering, a measure of segregated topology; and the Euclidean physical distance between connected nodes, a proxy marker of wiring cost). Nicotine enhanced attentional task performance behaviorally and increased efficiency, decreased clustering, and increased connection distance of brain networks. Greater behavioral benefits of nicotine were correlated with stronger drug effects on integrative and distributed network configuration and with greater frequency of cigarette smoking. Greater time-on-task had opposite effects: it impaired attentional accuracy, decreased efficiency, increased clustering, and decreased connection distance of networks. These results are consistent with hypothetical predictions that superior cognitive performance should be supported by more efficient, integrated (high capacity) brain network topology at greater connection distance (high cost). They also demonstrate that brain network analysis can provide novel and theoretically principled pharmacodynamic biomarkers of pro-cognitive drug effects in humans.
Collapse
Affiliation(s)
- Carsten Giessing
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge CB2 3EB, United Kingdom.
| | | | | | | | | |
Collapse
|
83
|
Nicotine restores Wt-like levels of reelin and GAD67 gene expression in brain of heterozygous reeler mice. Neurotox Res 2013; 24:205-15. [PMID: 23385624 DOI: 10.1007/s12640-013-9378-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 01/15/2013] [Accepted: 01/21/2013] [Indexed: 12/11/2022]
Abstract
Important reduction of reelin, a neural development- and plasticity-associated protein, and glutamic acid decarboxylase (GAD67) are reported in brains of schizophrenic patients. These individuals are consistently engaged in tobacco smoking and nicotine is thought to alleviate negative behavioral symptoms or cognitive alterations. In mouse brain, nicotine has been shown to reduce GAD67 promoter methylation and increase its transcription. We assessed the effects of administration of nicotine (1 mg/kg s.c.) for 6 days, in male mice heterozygous for reelin (HRM), a putative model for symptoms related to schizophrenia. Expression of reelin, GAD67 and brain-derived neurotrophic factor (BDNF) was measured in different brain areas. RNA expression analysis evidenced genotype-related changes, with a marked reduction in reelin and GAD67 gene expression in prefrontal cortex, hippocampus, cerebellum, and striatum from HRM. Nicotine treatment selectively reversed the HRM-related phenotype in most brain areas and increased BDNF gene expression in cortex and hippocampus of both genotypes. Locomotor performance in their home cage revealed that HRM subjects were characterized by general hyperactivity; with nicotine administration restoring WT-like levels of locomotion. These findings are interpreted within the hypothesis of pre-existing vulnerability (based on haploinsufficiency of reelin) to brain and behavioral disorders and regulative effects associated with nicotine exposure.
Collapse
|
84
|
Are cardiovascular risk factors associated with verbal learning and memory impairment in patients with schizophrenia? A cross-sectional study. Cardiovasc Psychiatry Neurol 2012; 2012:204043. [PMID: 23227310 PMCID: PMC3512211 DOI: 10.1155/2012/204043] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 09/25/2012] [Accepted: 10/20/2012] [Indexed: 01/03/2023] Open
Abstract
Objective. The aim of this study is to assess the relationships of cardiovascular risk factors with verbal learning and memory in patients with schizophrenia. Methods and Design. cross-sectional study. Inclusion Criteria. Diagnosis of schizophrenia according to the DSM-IV-TR criteria. Data Collection. Sociodemographic information, clinical characteristics, anthropometric measurements, blood tests, and episodic memory using the California Verbal Learning Test (CVLT). Analysis. A multivariate analysis using multiple linear regressions was performed to determine variables that are potentially associated with verbal learning and memory. Results. One hundred and sixty-eight outpatients participated in our study. An association was found between the metabolic syndrome (MetS) and memory impairment on measures of verbal learning, and short- and long-term memory. Among the different components of MeTS, hypertriglycerides, abdominal obesity, and low HDL cholesterol were the only factors associated with memory impairment. Alcohol dependence or abuse was associated with a higher rate of forgetting. Conclusion. Our findings suggest that MetS and alcohol use may be linked with memory impairment in schizophrenia. These findings provide important insights into the interdependencies of cardiovascular risk factors and cognitive disorders and support novel strategies for treating and preventing cognitive disorders in patients with schizophrenia.
Collapse
|
85
|
Donny EC, Taylor TG, LeSage MG, Levin M, Buffalari DM, Joel D, Sved AF. Impact of tobacco regulation on animal research: new perspectives and opportunities. Nicotine Tob Res 2012; 14:1319-38. [PMID: 22949581 PMCID: PMC3611983 DOI: 10.1093/ntr/nts162] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 05/29/2012] [Indexed: 12/29/2022]
Abstract
INTRODUCTION The Family Smoking Prevention and Tobacco Control Act in the United States and the World Health Organization Framework Convention on Tobacco or Health ratified by over 170 countries render scientific investigations into the abuse liability, harm, and effects of tobacco more critical than ever. A key area to explore relates to the potential regulation of nicotine content in cigarettes. Determining the nicotine content per cigarette below which smokers reliably reduce their consumption of and dependence on cigarettes, an idea proposed almost 20 years ago (Benowitz & Henningfield, 1994), could be a powerful approach to reduce the abuse liability and consequent harm from cigarettes. However, this approach is laden with potentially complex issues. Many of these complications can be studied using animal models, but they require a particular perspective. METHODS Herein, we review several challenges for animal researchers interested in nicotine reduction as examples of how this perspective dictates new approaches to animal research. These include defining the threshold nicotine dose for maintaining self-administration, evaluating the differential impact of various implementation strategies, assessing the factors that could interact with nicotine to alter the reinforcement threshold, describing the role of cues in maintaining low dose nicotine self-administration, and examining individual differences in response to nicotine reduction. CONCLUSIONS Researchers who study tobacco using animal models have the opportunity to play a central role in the regulatory science of tobacco and conduct studies that directly inform policy decisions that could impact the lives of millions.
Collapse
Affiliation(s)
- Eric C Donny
- Department of Psychology, Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, USA.
| | | | | | | | | | | | | |
Collapse
|
86
|
D'Souza DC, Ahn K, Bhakta S, Elander J, Singh N, Nadim H, Jatlow P, Suckow RF, Pittman B, Ranganathan M. Nicotine fails to attenuate ketamine-induced cognitive deficits and negative and positive symptoms in humans: implications for schizophrenia. Biol Psychiatry 2012; 72:785-94. [PMID: 22717030 DOI: 10.1016/j.biopsych.2012.05.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 05/03/2012] [Accepted: 05/08/2012] [Indexed: 11/30/2022]
Abstract
BACKGROUND The uncompetitive N-methyl-D-aspartate receptor (NMDAR) antagonist, ketamine, induces a range of symptoms resembling those seen in schizophrenia. Enhancement of nicotinic acetylcholine receptor (nAChR) function may have potential as a treatment for the cognitive deficits and negative symptoms of schizophrenia. Accordingly, we examined the modulatory effects of brain nAChR systems on NMDAR antagonist-induced effects. METHODS The interactive effects of ketamine and nicotine were evaluated in 37 healthy subjects in a randomized, placebo-controlled, double-blind, crossover counterbalanced, 2 (intravenous ketamine or placebo) × 2 (intravenous nicotine or placebo) design. Verbal and visual memory, sustained attention, working memory, response inhibition, emotion recognition, executive function, reaction time, motor function, and speed of processing were assessed once per test day, while negative and positive symptoms, perceptual alterations, and a number of feeling states were measured several times before and after administration of drugs. RESULTS Ketamine induced cognitive deficits and negative and positive symptoms. Nicotine worsened immediate recall, auditory working memory, response inhibition, and executive function and serial processing. Nicotine decreased (improved) reaction time on the sustained attention and choice reaction time tasks. Nicotine did not reduce ketamine-induced cognitive deficits or negative and positive symptoms. CONCLUSIONS At blood levels comparable with tobacco smoking, nicotine infusion does not appear to alleviate the ketamine-induced transient cognitive and behavioral effects in healthy subjects that resemble those seen in schizophrenia. The lack of an effect of nicotine on a spectrum of ketamine effects suggests that the consequences of NMDAR antagonism are not likely under the direct influence of nAChR.
Collapse
Affiliation(s)
- Deepak Cyril D'Souza
- Psychiatry Service, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
87
|
Knott V, Shah D, Millar A, McIntosh J, Fisher D, Blais C, Ilivitsky V. Nicotine, Auditory Sensory Memory, and sustained Attention in a Human Ketamine Model of Schizophrenia: Moderating Influence of a Hallucinatory Trait. Front Pharmacol 2012; 3:172. [PMID: 23060793 PMCID: PMC3460347 DOI: 10.3389/fphar.2012.00172] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 09/04/2012] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND The procognitive actions of the nicotinic acetylcholine receptor (nAChR) agonist nicotine are believed, in part, to motivate the excessive cigarette smoking in schizophrenia, a disorder associated with deficits in multiple cognitive domains, including low-level auditory sensory processes and higher-order attention-dependent operations. OBJECTIVES As N-methyl-d-aspartate receptor (NMDAR) hypofunction has been shown to contribute to these cognitive impairments, the primary aims of this healthy volunteer study were to: (a) to shed light on the separate and interactive roles of nAChR and NMDAR systems in the modulation of auditory sensory memory (and sustained attention), as indexed by the auditory event-related brain potential - mismatch negativity (MMN), and (b) to examine how these effects are moderated by a predisposition to auditory hallucinations/delusions (HD). METHODS In a randomized, double-blind, placebo-controlled design involving a low intravenous dose of ketamine (0.04 mg/kg) and a 4 mg dose of nicotine gum, MMN, and performance on a rapid visual information processing (RVIP) task of sustained attention were examined in 24 healthy controls psychometrically stratified as being lower (L-HD, n = 12) or higher (H-HD) for HD propensity. RESULTS Ketamine significantly slowed MMN, and reduced MMN in H-HD, with amplitude attenuation being blocked by the co-administration of nicotine. Nicotine significantly enhanced response speed [reaction time (RT)] and accuracy (increased % hits and d' and reduced false alarms) on the RVIP, with improved performance accuracy being prevented when nicotine was administered with ketamine. Both % hits and d', as well as RT were poorer in H-HD (vs. L-HD) and while hit rate and d' was increased by nicotine in H-HD, RT was slowed by ketamine in L-HD. CONCLUSIONS Nicotine alleviated ketamine-induced sensory memory impairment and improved attention, particularly in individuals prone to HD.
Collapse
Affiliation(s)
- Verner Knott
- Institute of Mental Health Research, University of OttawaOttawa, ON, Canada
- Neuroscience Program, Department of Cellular and Molecular Medicine, University of OttawaOttawa, ON, Canada
- School of Psychology, University of OttawaOttawa, ON, Canada
- Institute of Cognitive Science, Carleton UniversityOttawa, ON, Canada
- Royal Ottawa Mental Health CentreOttawa, ON, Canada
| | - Dhrasti Shah
- School of Psychology, University of OttawaOttawa, ON, Canada
| | - Anne Millar
- Neuroscience Program, Department of Cellular and Molecular Medicine, University of OttawaOttawa, ON, Canada
| | - Judy McIntosh
- Institute of Mental Health Research, University of OttawaOttawa, ON, Canada
| | - Derek Fisher
- Department of Psychology, Mount Saint Vincent UniversityHalifax, NS, Canada
| | - Crystal Blais
- Institute of Cognitive Science, Carleton UniversityOttawa, ON, Canada
| | | |
Collapse
|
88
|
Brunzell DH, McIntosh JM. Alpha7 nicotinic acetylcholine receptors modulate motivation to self-administer nicotine: implications for smoking and schizophrenia. Neuropsychopharmacology 2012; 37:1134-43. [PMID: 22169946 PMCID: PMC3306875 DOI: 10.1038/npp.2011.299] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Individuals diagnosed with schizophrenia have an exceptionally high risk for tobacco dependence. Postmortem studies show that these individuals have significant reductions in α7 nicotinic acetylcholine receptors (nAChRs) in several brain areas. Decreased α7-mediated function might not only be linked to schizophrenia but also to increased tobacco consumption. The purpose of this study was to determine whether pharmacological blockade of α7 nAChRs would increase motivation of rats to intravenously self-administer nicotine (NIC) during a progressive ratio schedule of reinforcement (PR). Before PR, rats received local infusions of 0, 10, or 20 pmol of a selective α7 nAChR antagonist, α-conotoxin ArIB [V11L,V16D] (ArIB) into the nucleus accumbens (NAc) shell or the anterior cingulate cortex, brain areas that contribute to motivation for drug reward. We additionally sought to determine whether local infusion of 0, 10, or 40 nmol of a selective α7 nAChR agonist, PNU 282987, into these brain areas would decrease motivation for NIC use. Infusion of ArIB into the NAc shell and anterior cingulate cortex resulted in a significant increase in active lever pressing, breakpoints, and NIC intake, suggesting that a decrease in α7 nAChR function increases motivation to work for NIC. In contrast, PNU 282987 infusion resulted in reductions in these measures when administered into the NAc shell, but had no effect after administration into the anterior cingulate cortex. These data identify reduction of α7 nAChR function as a potential mechanism for elevated tobacco use in schizophrenia and also identify activation of α7 nAChRs as a potential strategy for tobacco cessation therapy.
Collapse
Affiliation(s)
- Darlene H Brunzell
- Department of Pharmacology and Toxicology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA.
| | - J Michael McIntosh
- Department of Psychiatry, University of Utah, Salt Lake City, UT, USA,Department of Biology, University of Utah, Salt Lake City, UT, USA
| |
Collapse
|
89
|
Hall FS, Markou A, Levin ED, Uhl GR. Mouse models for studying genetic influences on factors determining smoking cessation success in humans. Ann N Y Acad Sci 2012; 1248:39-70. [PMID: 22304675 DOI: 10.1111/j.1749-6632.2011.06415.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Humans differ in their ability to quit using addictive substances, including nicotine, the major psychoactive ingredient in tobacco. For tobacco smoking, a substantial body of evidence, largely derived from twin studies, indicates that approximately half of these individual differences in ability to quit are heritable genetic influences that likely overlap with those for other addictive substances. Both twin and molecular genetic studies support overlapping influences on nicotine addiction vulnerability and smoking cessation success, although there is little formal analysis of the twin data that support this important point. None of the current datasets provides clarity concerning which heritable factors might provide robust dimensions around which individuals differ in ability to quit smoking. One approach to this problem is to test mice with genetic variations in genes that contain human variants that alter quit success. This review considers which features of quit success should be included in a comprehensive approach to elucidate the genetics of quit success, and how those features may be modeled in mice.
Collapse
Affiliation(s)
- F Scott Hall
- Molecular Neurobiology Branch, NIH-IRP, NIDA, Baltimore, Maryland 21224, USA
| | | | | | | |
Collapse
|
90
|
The nicotine metabolite, cotinine, attenuates glutamate (NMDA) antagonist-related effects on the performance of the five choice serial reaction time task (5C-SRTT) in rats. Biochem Pharmacol 2012; 83:941-51. [PMID: 22244928 DOI: 10.1016/j.bcp.2011.12.043] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 12/29/2011] [Accepted: 12/30/2011] [Indexed: 12/11/2022]
Abstract
Cotinine, the most predominant metabolite of nicotine in mammalian species, has a pharmacological half-life that greatly exceeds its precursor. However, until recently, relatively few studies had been conducted to systematically characterize the behavioral pharmacology of cotinine. Our previous work indicated that cotinine improves prepulse inhibition of the auditory startle response in rats in pharmacological impairment models and that it improves working memory in non-human primates. Here we tested the hypothesis that cotinine improves sustained attention in rats and attenuates behavioral alterations induced by the glutamate (NMDA) antagonist MK-801. The effects of acute subcutaneous (dose range 0.03-10.0 mg/kg) and chronic oral administration (2.0 mg/kg/day in drinking water) of cotinine were evaluated in fixed and variable stimulus duration (VSD) as well as variable intertrial interval (VITI) versions of a five choice serial reaction time task (5C-SRTT). The results indicated only subtle effects of acute cotinine (administered alone) on performance of the 5C-SRTT (e.g., decreases in timeout responses). However, depending on dose, acute treatment with cotinine attenuated MK-801-related impairments in accuracy and elevations in timeout responses, and it increased the number of completed trials. Moreover, chronic cotinine attenuated MK-801-related impairments in accuracy and it reduced premature and timeout responses when the demands of the task were increased (i.e., by presenting VSDs or VITIs in addition to administering MK-801). These data suggest that cotinine may represent a prototype for compounds that have therapeutic potential for neuropsychiatric disorders (i.e., by improving sustained attention and decreasing impulsive and compulsive behaviors), especially those characterized by glutamate receptor alterations.
Collapse
|
91
|
Nerve terminal nicotinic acetylcholine receptors initiate quantal GABA release from perisomatic interneurons by activating axonal T-type (Cav3) Ca²⁺ channels and Ca²⁺ release from stores. J Neurosci 2011; 31:13546-61. [PMID: 21940446 DOI: 10.1523/jneurosci.2781-11.2011] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Release of conventional neurotransmitters is mainly controlled by calcium (Ca²⁺) influx via high-voltage-activated (HVA), Ca(v)2, channels ("N-, P/Q-, or R-types") that are opened by action potentials. Regulation of transmission by subthreshold depolarizations does occur, but there is little evidence that low-voltage-activated, Ca(v)3 ("T-type"), channels take part. GABA release from cortical perisomatic-targeting interneurons affects numerous physiological processes, and yet its underlying control mechanisms are not fully understood. We investigated whether T-type Ca²⁺ channels are involved in regulating GABA transmission from these cells in rat hippocampal CA1 using a combination of whole-cell voltage-clamp, multiple-fluorescence confocal microscopy, dual-immunolabeling electron-microscopy, and optogenetic methods. We show that Ca(v)3.1, T-type Ca²⁺ channels can be activated by α3β4 nicotinic acetylcholine receptors (nAChRs) that are located on the synaptic regions of the GABAergic perisomatic-targeting interneuronal axons, including the parvalbumin-expressing cells. Asynchronous, quantal GABA release can be triggered by Ca²⁺ influx through presynaptic T-type Ca²⁺ channels, augmented by Ca²⁺ from internal stores, following focal microiontophoretic activation of the α3β4 nAChRs. The resulting GABA release can inhibit pyramidal cells. The T-type Ca²⁺ channel-dependent mechanism is not dependent on, or accompanied by, HVA channel Ca²⁺ influx, and is insensitive to agonists of cannabinoid, μ-opioid, or GABA(B) receptors. It may therefore operate in parallel with the normal HVA-dependent processes. The results reveal new aspects of the regulation of GABA transmission and contribute to a deeper understanding of ACh and nicotine actions in CNS.
Collapse
|
92
|
Young JW, Meves JM, Tarantino IS, Caldwell S, Geyer MA. Delayed procedural learning in α7-nicotinic acetylcholine receptor knockout mice. GENES BRAIN AND BEHAVIOR 2011; 10:720-33. [PMID: 21679297 DOI: 10.1111/j.1601-183x.2011.00711.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The α7-nicotinic acetylcholine receptor (nAChR) has long been a procognitive therapeutic target to treat schizophrenia. Evidence on the role of this receptor in cognition has been lacking, however, in part due to the limited availability of suitable ligands. The behavior of α7-nAChR knockout (KO) mice has been examined previously, but cognitive assessments using tests with cross-species translatability have been limited to date. Here, we assessed the cognitive performance of α7-nAChR KO and wild-type (WT) littermate mice in the attentional set-shifting task of executive functioning, the radial arm maze test of spatial working memory span capacity and the novel object recognition test of short-term memory. The reward motivation of these mutants was assessed using the progressive ratio breakpoint test. In addition, we assessed the exploratory behavior and sensorimotor gating using the behavioral pattern monitor and prepulse inhibition, respectively. α7-nAChR KO mice exhibited normal set-shifting, but impaired procedural learning (rule acquisition) in multiple paradigms. Spatial span capacity, short-term memory, motivation for food, exploration and sensorimotor gating were all comparable to WT littermates. The data presented here support the notion that this receptor is important for such procedural learning, when patterns in the environment become clear and a rule is learned. In combination with the impaired attention observed previously in these mice, this finding suggests that agonist treatments should be examined in clinical studies of attention and procedural learning, perhaps in combination with cognitive behavioral therapy.
Collapse
Affiliation(s)
- J W Young
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093-0804, USA.
| | | | | | | | | |
Collapse
|
93
|
Aleisa AM, Alzoubi KH, Alkadhi KA. Post-learning REM sleep deprivation impairs long-term memory: reversal by acute nicotine treatment. Neurosci Lett 2011; 499:28-31. [PMID: 21624432 DOI: 10.1016/j.neulet.2011.05.025] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 04/28/2011] [Accepted: 05/13/2011] [Indexed: 01/06/2023]
Abstract
Rapid eye movement sleep deprivation (REM-SD) is associated with spatial learning and memory impairment. During REM-SD, an increase in nicotine consumption among habitual smokers and initiation of tobacco use by non-smokers have been reported. We have shown recently that nicotine treatment prevented learning and memory impairments associated with REM-SD. We now report the interactive effects of post-learning REM-SD and/or nicotine. The animals were first trained on the radial arm water maze (RAWM) task, then they were REM-sleep deprived using the modified multiple platform paradigm for 24h. During REM-SD period, the rats were injected with saline or nicotine (1mg/kg s.c. every 12h: a total of 3 injections). The animals were tested for long-term memory in the RAWM at the end of the REM-SD period. The 24h post-learning REM-SD significantly impaired long-term memory. However, nicotine treatment reversed the post-learning REM-SD-induced impairment of long-term memory. On the other hand, post-learning treatment of normal rats with nicotine for 24h enhanced long-term memory. These results indicate that post-learning acute nicotine treatment prevented the deleterious effect of REM-SD on cognitive abilities.
Collapse
Affiliation(s)
- A M Aleisa
- Department of Pharmacology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | | | | |
Collapse
|