1
|
Schmidt SD, Zinn CG, Behling JAK, Furian AF, Furini CRG, de Carvalho Myskiw J, Izquierdo I. Inhibition of PACAP/PAC1/VPAC2 signaling impairs the consolidation of social recognition memory and nitric oxide prevents this deficit. Neurobiol Learn Mem 2021; 180:107423. [PMID: 33705861 DOI: 10.1016/j.nlm.2021.107423] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 02/18/2021] [Accepted: 03/03/2021] [Indexed: 11/17/2022]
Abstract
Social recognition memory (SRM) forms the basis of social relationships of animals. It is essential for social interaction and adaptive behavior, reproduction and species survival. Evidence demonstrates that social deficits of psychiatric disorders such as autism and schizophrenia are caused by alterations in SRM processing by the hippocampus and amygdala. Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) and its receptors PAC1, VPAC1 and VPAC2 are highly expressed in these regions. PACAP is a pleiotropic neuropeptide that modulates synaptic function and plasticity and is thought to be involved in social behavior. PACAP signaling also stimulates the nitric oxide (NO) production and targets outcomes to synapses. In the present work, we investigate the effect of the infusion of PACAP-38 (endogenous neuropeptide and potent stimulator of adenylyl cyclase), PACAP 6-38 (PAC1/VPAC2 receptors antagonist) and S-Nitroso-N-acetyl-DL-penicillamine (SNAP, NO donor) in the CA1 region of the hippocampus and in the basolateral amygdala (BLA) on the consolidation of SRM. For this, male Wistar rats with cannulae implanted in CA1 or in BLA were subjected to a social discrimination paradigm, which is based on the natural ability of rodents to investigate unfamiliar conspecifics more than familiar one. In the sample phase (acquisition), animals were exposed to a juvenile conspecific for 1 h. Immediately, 60 or 150 min after, animals received one of different pharmacological treatments. Twenty-four hours later, they were submitted to a 5 min retention test in the presence of the previously presented juvenile (familiar) and a novel juvenile. Animals that received infusions of PACAP 6-38 (40 pg/side) into CA1 immediately after the sample phase or into BLA immediately or 60 min after the sample phase were unable to recognize the familiar juvenile during the retention test. This impairment was abolished by the coinfusion of PACAP 6-38 plus SNAP (5 μg/side). These results show that the blockade of PACAP/PAC1/VPAC2 signaling in the CA1 and BLA during a restricted post-acquisition time window impairs the consolidation of SRM and that the SNAP is able to abolish this deficit. Findings like this could potentially be used in the future to influence studies of psychiatric disorders involving social behavior.
Collapse
Affiliation(s)
- Scheila Daiane Schmidt
- Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690-2nd Floor, 90610-000 Porto Alegre, RS, Brazil.
| | - Carolina Garrido Zinn
- Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690-2nd Floor, 90610-000 Porto Alegre, RS, Brazil
| | - Jonny Anderson Kielbovicz Behling
- Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690-2nd Floor, 90610-000 Porto Alegre, RS, Brazil
| | - Ana Flávia Furian
- Laboratory of Neurotoxicity, Federal University of Santa Maria (UFSM), Av. Roraima, 1000, 97105-900 Santa Maria, RS, Brazil
| | - Cristiane Regina Guerino Furini
- Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690-2nd Floor, 90610-000 Porto Alegre, RS, Brazil; National Institute of Translational Neuroscience (INNT), National Research Council of Brazil, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Jociane de Carvalho Myskiw
- Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690-2nd Floor, 90610-000 Porto Alegre, RS, Brazil; National Institute of Translational Neuroscience (INNT), National Research Council of Brazil, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil.
| | - Ivan Izquierdo
- Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690-2nd Floor, 90610-000 Porto Alegre, RS, Brazil; National Institute of Translational Neuroscience (INNT), National Research Council of Brazil, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil.
| |
Collapse
|
2
|
Oxidative-Antioxidant Imbalance and Impaired Glucose Metabolism in Schizophrenia. Biomolecules 2020; 10:biom10030384. [PMID: 32121669 PMCID: PMC7175146 DOI: 10.3390/biom10030384] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/24/2020] [Accepted: 02/26/2020] [Indexed: 02/07/2023] Open
Abstract
Schizophrenia is a neurodevelopmental disorder featuring chronic, complex neuropsychiatric features. The etiology and pathogenesis of schizophrenia are not fully understood. Oxidative-antioxidant imbalance is a potential determinant of schizophrenia. Oxidative, nitrosative, or sulfuric damage to enzymes of glycolysis and tricarboxylic acid cycle, as well as calcium transport and ATP biosynthesis might cause impaired bioenergetics function in the brain. This could explain the initial symptoms, such as the first psychotic episode and mild cognitive impairment. Another concept of the etiopathogenesis of schizophrenia is associated with impaired glucose metabolism and insulin resistance with the activation of the mTOR mitochondrial pathway, which may contribute to impaired neuronal development. Consequently, cognitive processes requiring ATP are compromised and dysfunctions in synaptic transmission lead to neuronal death, preceding changes in key brain areas. This review summarizes the role and mutual interactions of oxidative damage and impaired glucose metabolism as key factors affecting metabolic complications in schizophrenia. These observations may be a premise for novel potential therapeutic targets that will delay not only the onset of first symptoms but also the progression of schizophrenia and its complications.
Collapse
|
3
|
Knox LT, Jing Y, Bawazier-Edgecombe J, Collie ND, Zhang H, Liu P. Effects of withdrawal from repeated phencyclidine administration on behavioural function and brain arginine metabolism in rats. Pharmacol Biochem Behav 2016; 153:45-59. [PMID: 27986516 DOI: 10.1016/j.pbb.2016.12.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 07/20/2016] [Accepted: 12/12/2016] [Indexed: 12/13/2022]
Abstract
Phencyclidine (PCP) induces behavioural changes in humans and laboratory animals that resemble positive and negative symptoms, and cognitive impairments in schizophrenia. It has been shown repeated treatment of PCP leading to persistent symptoms even after the drug discontinuation, and there is a growing body of evidence implicating altered arginine metabolism in the pathogenesis of schizophrenia. The present study investigated the effects of withdrawal from repeated daily injection of PCP (2mg/kg) for 12 consecutive days on animals'behavioural performance and arginine metabolism in the hippocampus and prefrontal cortex in male young adult rats. Repeated PCP treatment reduced spontaneous alternations in the Y-maze and exploratory and locomotor activities in the open field under the condition of a washout period of 24h, but not 4days. Interestingly, the PCP treated rats also displayed spatial working memory deficits when tested 8-10days after withdrawal from PCP and showed altered levels of arginase activities and eight out of ten l-arginine metabolites in neurochemical- and region-specific manner. Cluster analyses showed altered relationships among l-arginine and its three main metabolites as a function of withdrawal from repeated PCP treatment in a duration-specific manner. Multiple regression analysis revealed significant neurochemical-behavioural correlations. Collectively, the results suggest both the residual and long-term effects of withdrawal from repeated PCP treatment on behavioural function and brain arginine metabolism. These findings demonstrate, for the first time, the influence of the withdrawal duration on animals' behaviour and brain arginine metabolism.
Collapse
Affiliation(s)
- Logan T Knox
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Yu Jing
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Jamal Bawazier-Edgecombe
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Nicola D Collie
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Hu Zhang
- School of Pharmacy, University of Otago, Dunedin, New Zealand; Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Ping Liu
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; Brain Health Research Centre, University of Otago, Dunedin, New Zealand.
| |
Collapse
|
4
|
Lafioniatis A, Orfanidou MA, Papadopoulou ES, Pitsikas N. Effects of the inducible nitric oxide synthase inhibitor aminoguanidine in two different rat models of schizophrenia. Behav Brain Res 2016; 309:14-21. [PMID: 27132765 DOI: 10.1016/j.bbr.2016.04.043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 04/22/2016] [Accepted: 04/26/2016] [Indexed: 10/21/2022]
Abstract
Several lines evidence indicate that the non-competitive N-methyl-d-aspartate (NMDA) receptor antagonist ketamine and the mixed dopamine (DA) D1/D2 receptor agonist apomorphine induce schizophrenia-like symptoms in rodents, including memory impairments and social withdrawal. Nitric oxide (NO) has been proposed to act as an intracellular messenger in the brain and its overproduction is associated with schizophrenia. The current study was designed to investigate the ability of the inducible NO synthase (iNOS) inhibitor aminoguanidine (AG) to counteract schizophrenia-like behavioural deficits produced by ketamine and apomorphine in rats. The efficacy of AG to antagonize extinction of recognition memory, ketamine and apomorphine-induced recognition memory impairments was tested utilizing the novel object recognition task (NORT). Further, the efficacy of AG to attenuate ketamine-induced social withdrawal was examined in the social interaction test. AG (25 and 50mg/kg) antagonized extinction of recognition memory and reversed ketamine (3mg/kg) and apomorphine (1mg/kg)-induced recognition memory deficits. In contrast, AG (50 and 100mg/kg) did not counteract the ketamine (8mg/kg)-induced social isolation. The present data show that the iNOS inhibitor AG counteracted extinction of recognition memory and reversed recognition memory deficits produced by dysfunction of the glutamatergic and the dopaminergic (DAergic) system in rats. Therefore, AG may be efficacious in attenuating memory impairments often observed in schizophrenia patients.
Collapse
Affiliation(s)
- Anastasios Lafioniatis
- Department of Pharmacology, School of Medicine, Faculty of Health Sciences, University of Thessaly, Larissa, Greece
| | - Martha A Orfanidou
- Department of Pharmacology, School of Medicine, Faculty of Health Sciences, University of Thessaly, Larissa, Greece
| | - Evangelia S Papadopoulou
- Department of Pharmacology, School of Medicine, Faculty of Health Sciences, University of Thessaly, Larissa, Greece
| | - Nikolaos Pitsikas
- Department of Pharmacology, School of Medicine, Faculty of Health Sciences, University of Thessaly, Larissa, Greece.
| |
Collapse
|
5
|
Karlsson SA, Studer E, Kettunen P, Westberg L. Neural Androgen Receptors Modulate Gene Expression and Social Recognition But Not Social Investigation. Front Behav Neurosci 2016; 10:41. [PMID: 27014003 PMCID: PMC4792870 DOI: 10.3389/fnbeh.2016.00041] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 02/22/2016] [Indexed: 12/02/2022] Open
Abstract
The role of sex and androgen receptors (ARs) for social preference and social memory is rather unknown. In this study of mice we compared males, females and males lacking ARs specifically in the nervous system, ARNesDel, with respect to social preference, assessed with the three-chambered apparatus test, and social recognition, assessed with the social discrimination procedure. In the social discrimination test we also evaluated the tentative importance of the sex of the stimulus animal. Novel object recognition and olfaction were investigated to complement the results from the social tests. Gene expression analysis was performed to reveal molecules involved in the effects of sex and androgens on social behaviors. All three test groups showed social preference in the three-chambered apparatus test. In both social tests an AR-independent sexual dimorphism was seen in the persistence of social investigation of female conspecifics, whereas the social interest toward male stimuli mice was similar in all groups. Male and female controls recognized conspecifics independent of their sex, whereas ARNesDel males recognized female but not male stimuli mice. Moreover, the non-social behaviors were not affected by AR deficiency. The gene expression analyses of hypothalamus and amygdala indicated that Oxtr, Cd38, Esr1, Cyp19a1, Ucn3, Crh, and Gtf2i were differentially expressed between the three groups. In conclusion, our results suggest that ARs are required for recognition of male but not female conspecifics, while being dispensable for social investigation toward both sexes. In addition, the AR seems to regulate genes related to oxytocin, estrogen and William’s syndrome.
Collapse
Affiliation(s)
- Sara A Karlsson
- Department of Pharmacology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg Gothenburg, Sweden
| | - Erik Studer
- Department of Pharmacology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg Gothenburg, Sweden
| | - Petronella Kettunen
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg Gothenburg, Sweden
| | - Lars Westberg
- Department of Pharmacology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg Gothenburg, Sweden
| |
Collapse
|
6
|
Bernardinelli Y, Nikonenko I, Muller D. Structural plasticity: mechanisms and contribution to developmental psychiatric disorders. Front Neuroanat 2014; 8:123. [PMID: 25404897 PMCID: PMC4217507 DOI: 10.3389/fnana.2014.00123] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 10/14/2014] [Indexed: 01/31/2023] Open
Abstract
Synaptic plasticity mechanisms are usually discussed in terms of changes in synaptic strength. The capacity of excitatory synapses to rapidly modify the membrane expression of glutamate receptors in an activity-dependent manner plays a critical role in learning and memory processes by re-distributing activity within neuronal networks. Recent work has however also shown that functional plasticity properties are associated with a rewiring of synaptic connections and a selective stabilization of activated synapses. These structural aspects of plasticity have the potential to continuously modify the organization of synaptic networks and thereby introduce specificity in the wiring diagram of cortical circuits. Recent work has started to unravel some of the molecular mechanisms that underlie these properties of structural plasticity, highlighting an important role of signaling pathways that are also major candidates for contributing to developmental psychiatric disorders. We review here some of these recent advances and discuss the hypothesis that alterations of structural plasticity could represent a common mechanism contributing to the cognitive and functional defects observed in diseases such as intellectual disability, autism spectrum disorders and schizophrenia.
Collapse
Affiliation(s)
- Yann Bernardinelli
- Department of Basic Neurosciences, University of Geneva Medical School Geneva, Switzerland
| | - Irina Nikonenko
- Department of Basic Neurosciences, University of Geneva Medical School Geneva, Switzerland
| | - Dominique Muller
- Department of Basic Neurosciences, University of Geneva Medical School Geneva, Switzerland
| |
Collapse
|
7
|
Effects of acute phencyclidine administration on arginine metabolism in the hippocampus and prefrontal cortex in rats. Neuropharmacology 2014; 81:195-205. [DOI: 10.1016/j.neuropharm.2014.02.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 01/03/2014] [Accepted: 02/05/2014] [Indexed: 12/19/2022]
|
8
|
Nitric oxide mediates local activity-dependent excitatory synapse development. Proc Natl Acad Sci U S A 2013; 110:E4142-51. [PMID: 24127602 DOI: 10.1073/pnas.1311927110] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Learning related paradigms play an important role in shaping the development and specificity of synaptic networks, notably by regulating mechanisms of spine growth and pruning. The molecular events underlying these synaptic rearrangements remain poorly understood. Here we identify NO signaling as a key mediator of activity-dependent excitatory synapse development. We find that chronic blockade of NO production in vitro and in vivo interferes with the development of hippocampal and cortical excitatory spine synapses. The effect results from a selective loss of activity-mediated spine growth mechanisms and is associated with morphological and functional alterations of remaining synapses. These effects of NO are mediated by a cGMP cascade and can be reproduced or prevented by postsynaptic expression of vasodilator-stimulated phosphoprotein phospho-mimetic or phospho-resistant mutants. In vivo analyses show that absence of NO prevents the increase in excitatory synapse density induced by environmental enrichment and interferes with the formation of local clusters of excitatory synapses. We conclude that NO plays an important role in regulating the development of excitatory synapses by promoting local activity-dependent spine-growth mechanisms.
Collapse
|
9
|
Minutolo G, Petralia A, Dipasquale S, Aguglia E. Nitric oxide in patients with schizophrenia: the relationship with the severity of illness and the antipsychotic treatment. Expert Opin Pharmacother 2012; 13:1989-97. [DOI: 10.1517/14656566.2012.713346] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
10
|
Okochi T, Kishi T, Ikeda M, Kitajima T, Kinoshita Y, Kawashima K, Okumura T, Tsunoka T, Fukuo Y, Inada T, Yamada M, Uchimura N, Iyo M, Sora I, Ozaki N, Ujike H, Iwata N. Genetic Association Analysis of NOS3 and Methamphetamine-Induced Psychosis Among Japanese. Curr Neuropharmacol 2011; 9:151-4. [PMID: 21886581 PMCID: PMC3137171 DOI: 10.2174/157015911795017119] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 04/17/2010] [Accepted: 05/26/2010] [Indexed: 11/28/2022] Open
Abstract
Endothelial nitric oxide synthase (NOS3) is one of the enzymes influencing nitric oxide (NO) function in the human brain. NO is a gaseous neurotransmitter that is involved in a variety of mechanisms in the central nervous system, such as N-methyl-D-aspartate receptor activation and oxidative stress. The evidence from animal pharmacological studies and postmortem studies supports an association between NO and psychotic disorders. Methamphetamine (METH) use disorder is a known psychotic disorder, and we therefore conducted a gene-based case-control study between tagging single nucleotide polymorphisms (SNPs) (rs2070744, rs1799983) in NOS3 and METH-induced psychosis in Japanese subjects (183 with METH-induced psychosis and 267 controls). Written informed consent was obtained from each subject. No significant association was found between any tagging SNP in NOS3 and METH-induced psychosis in the allele/genotype-wise or haplotype-wise analyses. In conclusion, we suggest that NOS3 might not contribute to the risk of METH-induced psychosis in the Japanese population.
Collapse
Affiliation(s)
- T Okochi
- Department of Psychiatry, Fujita Health University School of Medicine, Toyoake, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Crespi BJ, Thiselton DL. Comparative immunogenetics of autism and schizophrenia. GENES BRAIN AND BEHAVIOR 2011; 10:689-701. [DOI: 10.1111/j.1601-183x.2011.00710.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
12
|
Wass C, Klamer D, Katsarogiannis E, Pålsson E, Svensson L, Fejgin K, Bogren IB, Engel JA, Rembeck B. L-lysine as adjunctive treatment in patients with schizophrenia: a single-blinded, randomized, cross-over pilot study. BMC Med 2011; 9:40. [PMID: 21501494 PMCID: PMC3094237 DOI: 10.1186/1741-7015-9-40] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Accepted: 04/18/2011] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Accumulating evidence suggests that the brain's nitric oxide (NO) signalling system may be involved in the pathophysiology of schizophrenia and could thus constitute a novel treatment target. The study was designed to investigate the benefit of L-lysine, an amino acid that interferes with NO production, as an add-on treatment for schizophrenia. METHODS L-lysine, 6 g/day, was administered to 10 patients with schizophrenia as an adjunctive to their conventional antipsychotic medication. The study was designed as a single-blinded, cross-over study where patients were randomly assigned to initial treatment with either L-lysine or placebo and screened at baseline, after four weeks when treatment was crossed over, and after eight weeks. RESULTS L-lysine treatment caused a significant increase in blood concentration of L-lysine and was well tolerated. A significant decrease in positive symptom severity, measured by the Positive And Negative Syndrome Scale (PANSS), was detected. A certain decrease in score was also observed during placebo treatment and the effects on PANSS could not unequivocally be assigned to the L-lysine treatment. Furthermore, performance on the Wisconsin Card Sorting Test was significantly improved compared to baseline, an effect probably biased by training. Subjective reports from three of the patients indicated decreased symptom severity and enhanced cognitive functioning. CONCLUSIONS Four-week L-lysine treatment of 6 g/day caused a significant increase in blood concentration of L-lysine that was well tolerated. Patients showed a significant decrease in positive symptoms as assessed by PANSS in addition to self-reported symptom improvement by three patients. The NO-signalling pathway is an interesting, potentially new treatment target for schizophrenia; however, the effects of L-lysine need further evaluation to decide the amino acid's potentially beneficial effects on symptom severity in schizophrenia.
Collapse
Affiliation(s)
- Caroline Wass
- Schizophrenia Program, Centre for Addiction and Mental Health, Toronto, Canada.
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Information processing deficits and nitric oxide signalling in the phencyclidine model of schizophrenia. Psychopharmacology (Berl) 2010; 212:643-51. [PMID: 20802999 DOI: 10.1007/s00213-010-1992-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Accepted: 08/04/2010] [Indexed: 12/22/2022]
Abstract
RATIONALE Schizophrenia-like cognitive deficits induced by phencyclidine (PCP), a drug commonly used to model schizophrenia in experimental animals, are attenuated by nitric oxide (NO) synthase inhibitors. Furthermore, PCP increases NO levels and sGC/cGMP signalling in the prefrontal cortex in rodents. Hence, a cortical NO/sGC/cGMP signalling pathway may constitute a target for novel pharmacological therapies in schizophrenia. OBJECTIVES The objective of this study was to further investigate the role of NO signalling for a PCP-induced deficit in pre-attentive information processing. MATERIALS AND METHODS Male Sprague-Dawley rats were surgically implanted with NO-selective amperometric microsensors aimed at the prefrontal cortex, ventral hippocampus or nucleus accumbens, and NO levels and prepulse inhibition (PPI) were simultaneously assessed. RESULTS PCP treatment increased NO levels in the prefrontal cortex and ventral hippocampus, but not in the nucleus accumbens. The increase in NO levels was not temporally correlated to the deficit in PPI induced by PCP. Furthermore, pretreatment with the neuronal NO synthase inhibitor N-propyl-L-arginine dose-dependently attenuated both the increase in prefrontal cortex NO levels and the deficit in PPI. CONCLUSIONS These findings support a demonstrated role of NO in the behavioural and neurochemical effects of PCP. Furthermore, this effect is brain region-specific and mainly involves the neuronal isoform of NOS. However, a temporal correlation between a PCP-induced disruption of PPI and an increase in prefrontal cortex NO levels was not demonstrated, suggesting that the interaction between PCP and the NO system is more complex than previously thought.
Collapse
|
14
|
Bitanihirwe BKY, Woo TUW. Oxidative stress in schizophrenia: an integrated approach. Neurosci Biobehav Rev 2010; 35:878-93. [PMID: 20974172 DOI: 10.1016/j.neubiorev.2010.10.008] [Citation(s) in RCA: 317] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2010] [Revised: 09/18/2010] [Accepted: 10/17/2010] [Indexed: 01/17/2023]
Abstract
Oxidative stress has been suggested to contribute to the pathophysiology of schizophrenia. In particular, oxidative damage to lipids, proteins, and DNA as observed in schizophrenia is known to impair cell viability and function, which may subsequently account for the deteriorating course of the illness. Currently available evidence points towards an alteration in the activities of enzymatic and nonenzymatic antioxidant systems in schizophrenia. In fact, experimental models have demonstrated that oxidative stress induces behavioral and molecular anomalies strikingly similar to those observed in schizophrenia. These findings suggest that oxidative stress is intimately linked to a variety of pathophysiological processes, such as inflammation, oligodendrocyte abnormalities, mitochondrial dysfunction, hypoactive N-methyl-d-aspartate receptors and the impairment of fast-spiking gamma-aminobutyric acid interneurons. Such self-sustaining mechanisms may progressively worsen producing the functional and structural consequences associated with schizophrenia. Recent clinical studies have shown antioxidant treatment to be effective in ameliorating schizophrenic symptoms. Hence, identifying viable therapeutic strategies to tackle oxidative stress and the resulting physiological disturbances provide an exciting opportunity for the treatment and ultimately prevention of schizophrenia.
Collapse
Affiliation(s)
- Byron K Y Bitanihirwe
- Laboratory of Behavioural Neurobiology, Swiss Federal Institute of Technology, Zurich, Schorenstrasse 16, Schwerzenbach CH 8603, Switzerland.
| | | |
Collapse
|
15
|
A putative cis-acting polymorphism in the NOS1 gene is associated with schizophrenia and NOS1 immunoreactivity in the postmortem brain. Schizophr Res 2010; 121:172-8. [PMID: 20605417 DOI: 10.1016/j.schres.2010.05.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Revised: 03/16/2010] [Accepted: 05/07/2010] [Indexed: 11/23/2022]
Abstract
Schizophrenia is a devastating neurodevelopmental disorder whose genetic influences remain elusive. Recent genome-wide scans revealed that rare structural variants disrupted multiple genes in neurodevelopmental pathways, which strongly implicate nitric oxide (NO) signaling in schizophrenia. NO acts as a second messenger of N-methyl-D aspartate receptor activation, which further interacts with both dopaminergic and serotonergic pathways. NO is mainly synthesized by neuronal nitric oxide synthase (NOS1) in the brain, and its gene locus, 12q24.2, has attracted much attention as a major linkage region for schizophrenia. Genetic variations of NOS1 have also been associated with schizophrenia, and differential expression of NOS1 was observed in the postmortem brain of schizophrenic patients. Here, we explored the hypothesis that a putative cis-acting G-84A single nucleotide polymorphism (SNP; rs41279104) in the exon 1c promoter region of the NOS1 gene is associated with the levels of NOS1 immunoreactivity in postmortem prefrontal cortex specimens regardless of disease phenotype. Individuals with the A-allele of this SNP showed significantly lower levels of NOS1 immunoreactivity than did GG homozygotes (p=0.002). Furthermore, a case-control study using 720 individuals in a Japanese population revealed a significant association between the SNP and schizophrenia (genotypic p=0.0013 and allelic p=0.0011). Additionally, the average of onset age in schizophrenic patients with the A-allele was significantly earlier than GG homozygotes (p=0.018). When the analyses took gender into account, this significance was more significant for female. These findings provide further evidences that NOS1 is associated with a biological susceptibility gene to schizophrenia.
Collapse
|
16
|
O'Tuathaigh CMP, Kirby BP, Moran PM, Waddington JL. Mutant mouse models: genotype-phenotype relationships to negative symptoms in schizophrenia. Schizophr Bull 2010; 36:271-88. [PMID: 19934211 PMCID: PMC2833123 DOI: 10.1093/schbul/sbp125] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Negative symptoms encompass diminution in emotional expression and motivation, some of which relate to human attributes that may not be accessible readily in animals. Additionally, their refractoriness to treatment precludes therapeutic validation of putative models. This review considers critically the application of mutant mouse models to the study of the pathobiology of negative symptoms. It focuses on 4 main approaches: genes related to the pathobiology of schizophrenia, genes associated with risk for schizophrenia, neurodevelopmental-synaptic genes, and variant approaches from other areas of neurobiology. Despite rapid advances over the past several years, it is clear that we continue to face substantive challenges in applying mutant models to better understand the pathobiology of negative symptoms: the majority of evidence relates to impairments in social behavior, with only limited data relating to anhedonia and negligible data concerning avolition and other features; even for the most widely examined feature, social behavior, studies have used diverse assessments thereof; modelling must proceed in cognizance of increasing evidence that genes and pathobiologies implicated in schizophrenia overlap with other psychotic disorders, particularly bipolar disorder. Despite the caveats and challenges, several mutant lines evidence a phenotype for at least one index of social behavior. Though this may suggest superficially some shared relationship to negative symptoms, it is not yet possible to specify either the scope or the pathobiology of that relationship for any given gene. The breadth and depth of ongoing studies in mutants hold the prospect of addressing these shortcomings.
Collapse
Affiliation(s)
- Colm M. P. O'Tuathaigh
- Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, St Stephen's Green, Dublin 2, Ireland,To whom correspondence should be addressed; tel: +353-1-402-2377, fax: +353-1-402-2453, e-mail:
| | - Brian P. Kirby
- School of Pharmacy, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Paula M. Moran
- School of Psychology, University of Nottingham, Nottingham, UK
| | - John L. Waddington
- Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, St Stephen's Green, Dublin 2, Ireland
| |
Collapse
|
17
|
No Association Between Polymorphisms of Neuronal Oxide Synthase 1 Gene (NOS1) and Schizophrenia in a Japanese Population. Neuromolecular Med 2009; 11:123-7. [DOI: 10.1007/s12017-009-8068-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Accepted: 05/21/2009] [Indexed: 02/04/2023]
|