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Therapeutic Potential of Cannabinoids in Psychosis. Biol Psychiatry 2016; 79:604-12. [PMID: 26852073 DOI: 10.1016/j.biopsych.2015.11.018] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 11/24/2015] [Accepted: 11/24/2015] [Indexed: 11/22/2022]
Abstract
Over recent years, the interest in the endocannabinoid system (ECS) as a new target for the treatment of schizophrenia has evolved. The ECS represents one of the most relevant neurotransmitter systems in the brain and mainly fulfills a homeostatic role in terms of neurotransmission but also with respect to inflammatory processes. Two main approaches to the modulation of endocannabinoid functioning have been chosen so far. First, the selective blockade or inverse agonism of the type 1 cannabinoid receptor has been tested for the improvement of acute psychotic symptoms, as well as for the improvement of cognitive functions in schizophrenia. This was not effective in either case. Second, the modulation of endocannabinoid levels by use of the phytocannabinoid cannabidiol and selective fatty acid amide hydrolase inhibitors has been proposed, and the antipsychotic properties of cannabidiol are currently being investigated in humans. Unfortunately, for most of these trials that have focused on psychopathological and cognitive effects of cannabidiol, no published data are available. However, there is first evidence that cannabidiol may ameliorate psychotic symptoms with a superior side-effect profile compared with established antipsychotics. In conclusion, several clinical trials targeting the ECS in acute schizophrenia have either been completed or are underway. Although publicly available results are currently limited, preliminary data indicate that selected compounds modulating the ECS may be effective in acute schizophrenia. Nevertheless, so far, sample sizes of patients investigated are not sufficient to come to a final judgment, and no maintenance studies are available to ensure long-term efficacy and safety.
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Fakhoury M. Role of the Endocannabinoid System in the Pathophysiology of Schizophrenia. Mol Neurobiol 2016; 54:768-778. [DOI: 10.1007/s12035-016-9697-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 01/05/2016] [Indexed: 12/12/2022]
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53
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Lovelace JW, Corches A, Vieira PA, Hiroto AS, Mackie K, Korzus E. An animal model of female adolescent cannabinoid exposure elicits a long-lasting deficit in presynaptic long-term plasticity. Neuropharmacology 2015; 99:242-55. [PMID: 25979486 DOI: 10.1016/j.neuropharm.2015.04.034] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 04/16/2015] [Accepted: 04/29/2015] [Indexed: 11/29/2022]
Abstract
Cannabis continues to be the most accessible and popular illicit recreational drug. Whereas current data link adolescence cannabinoid exposure to increased risk for dependence on other drugs, depression, anxiety disorders and psychosis, the mechanism(s) underlying these adverse effects remains controversial. Here we show in a mouse model of female adolescent cannabinoid exposure deficient endocannabinoid (eCB)-mediated signaling and presynaptic forms of long-term depression at adult central glutamatergic synapses in the prefrontal cortex. Increasing endocannabinoid levels by blockade of monoacylglycerol lipase, the primary enzyme responsible for degrading the endocannabinoid 2-arachidonoylglycerol (2-AG), with the specific inhibitor JZL 184 ameliorates eCB-LTD deficits. The observed deficit in cortical presynaptic signaling may represent a neural maladaptation underlying network instability and abnormal cognitive functioning. Our study suggests that adolescent cannabinoid exposure may permanently impair brain functions, including the brain's intrinsic ability to appropriately adapt to external influences.
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Affiliation(s)
- Jonathan W Lovelace
- Department of Psychology & Neuroscience Program, University of California Riverside, CA 92521, USA
| | - Alex Corches
- Biomedical Sciences Program, University of California Riverside, CA 92521, USA
| | - Philip A Vieira
- Department of Psychology & Neuroscience Program, University of California Riverside, CA 92521, USA
| | - Alex S Hiroto
- Department of Psychology & Neuroscience Program, University of California Riverside, CA 92521, USA
| | - Ken Mackie
- Department of Psychological & Brain Sciences, Gill Center for Biomedical Sciences, Indiana University, Bloomington, IN 47405, USA
| | - Edward Korzus
- Department of Psychology & Neuroscience Program, University of California Riverside, CA 92521, USA; Biomedical Sciences Program, University of California Riverside, CA 92521, USA.
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Iseger TA, Bossong MG. A systematic review of the antipsychotic properties of cannabidiol in humans. Schizophr Res 2015; 162:153-61. [PMID: 25667194 DOI: 10.1016/j.schres.2015.01.033] [Citation(s) in RCA: 155] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 01/20/2015] [Accepted: 01/21/2015] [Indexed: 12/25/2022]
Abstract
Despite extensive study over the past decades, available treatments for schizophrenia are only modestly effective and cause serious metabolic and neurological side effects. Therefore, there is an urgent need for novel therapeutic targets for the treatment of schizophrenia. A highly promising new pharmacological target in the context of schizophrenia is the endocannabinoid system. Modulation of this system by the main psychoactive component in cannabis, Δ9-tetrahydrocannabinol (THC), induces acute psychotic effects and cognitive impairment. However, the non-psychotropic, plant-derived cannabinoid agent cannabidiol (CBD) may have antipsychotic properties, and thus may be a promising new agent in the treatment of schizophrenia. Here we review studies that investigated the antipsychotic properties of CBD in human subjects. Results show the ability of CBD to counteract psychotic symptoms and cognitive impairment associated with cannabis use as well as with acute THC administration. In addition, CBD may lower the risk for developing psychosis that is related to cannabis use. These effects are possibly mediated by opposite effects of CBD and THC on brain activity patterns in key regions implicated in the pathophysiology of schizophrenia, such as the striatum, hippocampus and prefrontal cortex. The first small-scale clinical studies with CBD treatment of patients with psychotic symptoms further confirm the potential of CBD as an effective, safe and well-tolerated antipsychotic compound, although large randomised clinical trials will be needed before this novel therapy can be introduced into clinical practice.
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Affiliation(s)
- Tabitha A Iseger
- Institute of Psychiatry, Department of Psychosis Studies, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom
| | - Matthijs G Bossong
- Institute of Psychiatry, Department of Psychosis Studies, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom; Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
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Functional genetic variation of the cannabinoid receptor 1 and cannabis use interact on prefrontal connectivity and related working memory behavior. Neuropsychopharmacology 2015; 40:640-9. [PMID: 25139064 PMCID: PMC4289952 DOI: 10.1038/npp.2014.213] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 06/29/2014] [Accepted: 07/14/2014] [Indexed: 02/06/2023]
Abstract
Cannabinoid signaling is involved in different brain functions and it is mediated by the cannabinoid receptor 1 (CNR1), which is encoded by the CNR1 gene. Previous evidence suggests an association between cognition and cannabis use. The logical interaction between genetically determined cannabinoid signaling and cannabis use has not been determined. Therefore, we investigated whether CNR1 variation predicts CNR1 prefrontal mRNA expression in postmortem prefrontal human tissue. Then, we studied whether functional variation in CNR1 and cannabis exposure interact in modulating prefrontal function and related behavior during working memory processing. Thus, 208 healthy subjects (113 males) were genotyped for the relevant functional SNP and were evaluated for cannabis use by the Cannabis Experience Questionnaire. All individuals performed the 2-back working memory task during functional magnetic resonance imaging. CNR1 rs1406977 was associated with prefrontal mRNA and individuals carrying a G allele had reduced CNR1 prefrontal mRNA levels compared with AA subjects. Moreover, functional connectivity MRI demonstrated that G carriers who were also cannabis users had greater functional connectivity in the left ventrolateral prefrontal cortex and reduced working memory behavioral accuracy during the 2-back task compared with the other groups. Overall, our results indicate that the deleterious effects of cannabis use are more evident on a specific genetic background related to its receptor expression.
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Nottage JF, Stone J, Murray RM, Sumich A, Bramon-Bosch E, ffytche D, Morrison PD. Delta-9-tetrahydrocannabinol, neural oscillations above 20 Hz and induced acute psychosis. Psychopharmacology (Berl) 2015; 232:519-28. [PMID: 25038870 PMCID: PMC4302232 DOI: 10.1007/s00213-014-3684-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Accepted: 07/05/2014] [Indexed: 01/05/2023]
Abstract
RATIONALE An acute challenge with delta-9-tetrahydrocannabinol (THC) can induce psychotic symptoms including delusions. High electroencephalography (EEG) frequencies, above 20 Hz, have previously been implicated in psychosis and schizophrenia. OBJECTIVES The objective of this study is to determine the effect of intravenous THC compared to placebo on high-frequency EEG. METHODS A double-blind cross-over study design was used. In the resting state, the high-beta to low-gamma magnitude (21-45 Hz) was investigated (n = 13 pairs + 4 THC only). Also, the event-related synchronisation (ERS) of motor-associated high gamma was studied using a self-paced button press task (n = 15). RESULTS In the resting state, there was a significant condition × frequency interaction (p = 0.00017), consisting of a shift towards higher frequencies under THC conditions (reduced high beta [21-27 Hz] and increased low gamma [27-45 Hz]). There was also a condition × frequency × location interaction (p = 0.006), such that the reduction in 21-27-Hz magnitude tended to be more prominent in anterior regions, whilst posterior areas tended to show greater 27-45-Hz increases. This effect was correlated with positive symptoms, as assessed on the Positive and Negative Syndrome Scale (PANSS) (r = 0.429, p = 0.042). In the motor task, there was a main effect of THC to increase 65-130-Hz ERS (p = 0.035) over contra-lateral sensorimotor areas, which was driven by increased magnitude in the higher, 85-130-Hz band (p = 0.02) and not the 65-85-Hz band. CONCLUSIONS The THC-induced shift to faster gamma oscillations may represent an over-activation of the cortex, possibly related to saliency misattribution in the delusional state.
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Affiliation(s)
- Judith F. Nottage
- Institute of Psychiatry, King’s College London, P089 DeCrespigny Park, Denmark Hill, London, SE5 8AF UK
| | - James Stone
- Institute of Psychiatry, King’s College London, P089 DeCrespigny Park, Denmark Hill, London, SE5 8AF UK
| | - Robin M. Murray
- Institute of Psychiatry, King’s College London, P089 DeCrespigny Park, Denmark Hill, London, SE5 8AF UK
| | - Alex Sumich
- Nottingham Trent University, Nottingham, NG1 4BU UK
| | | | - Dominic ffytche
- Institute of Psychiatry, King’s College London, P089 DeCrespigny Park, Denmark Hill, London, SE5 8AF UK
| | - Paul D. Morrison
- Institute of Psychiatry, King’s College London, P089 DeCrespigny Park, Denmark Hill, London, SE5 8AF UK
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Abstract
Preclinical and clinical data fully support the involvement of the endocannabinoid system in the etiopathogenesis of several mental diseases. In this review we will briefly summarize the most common alterations in the endocannabinoid system, in terms of cannabinoid receptors and endocannabinoid levels, present in mood disorders (anxiety, posttraumatic stress disorder, depression, bipolar disorder, and suicidality) as well as psychosis (schizophrenia) and autism. The arising picture for each pathology is not always straightforward; however, both animal and human studies seem to suggest that pharmacological modulation of this system might represent a novel approach for treatment.
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Affiliation(s)
- Tiziana Rubino
- Department of Theoretical and Applied Sciences and Neuroscience Centre, University of Insubria, Via Manara 7, 21052, Busto Arsizio, VA, Italy
| | - Erica Zamberletti
- Department of Theoretical and Applied Sciences and Neuroscience Centre, University of Insubria, Via Manara 7, 21052, Busto Arsizio, VA, Italy
- Fondazione Zardi Gori, Milan, Italy
| | - Daniela Parolaro
- Department of Theoretical and Applied Sciences and Neuroscience Centre, University of Insubria, Via Manara 7, 21052, Busto Arsizio, VA, Italy.
- Fondazione Zardi Gori, Milan, Italy.
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58
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Volk DW, Eggan SM, Horti AG, Wong DF, Lewis DA. Reciprocal alterations in cortical cannabinoid receptor 1 binding relative to protein immunoreactivity and transcript levels in schizophrenia. Schizophr Res 2014; 159:124-9. [PMID: 25107849 PMCID: PMC4177350 DOI: 10.1016/j.schres.2014.07.017] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 07/08/2014] [Accepted: 07/09/2014] [Indexed: 11/18/2022]
Abstract
The deleterious effects of cannabis use in schizophrenia have been linked, in part, to underlying disturbances in endogenous cannabinoid signaling in the prefrontal cortex. However, while receptor autoradiography studies of the primary cannabinoid receptor (CB1R) have consistently found higher CB1R binding in the prefrontal cortex in schizophrenia, deficits in CB1R mRNA levels and protein immunoreactivity have also been reported in the illness. To investigate this apparent discrepancy, we quantified CB1R binding using receptor autoradiography with the selective CB1R ligand [(3)H]-OMAR in the prefrontal cortex of 21 subjects with schizophrenia who were previously found to have lower levels of both CB1R mRNA using in situ hybridization and CB1R protein using radioimmunocytochemistry relative to matched healthy comparison subjects. We observed higher levels of [(3)H]-OMAR binding in the prefrontal cortex of schizophrenia subjects that did not appear to be attributable to psychotropic medications or substance abuse. The combination of lower levels of CB1R mRNA and immunoreactivity with higher CB1R receptor binding may reflect 1) altered trafficking of the receptor resulting in higher levels of membrane-bound CB1R or 2) higher CB1R affinity. In either case, greater CB1R receptor availability may contribute to the increased susceptibility of schizophrenia subjects to the deleterious effects of cannabis use.
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Affiliation(s)
- David W Volk
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15213, United States.
| | - Stephen M Eggan
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15213, United States
| | - Andrew G Horti
- Department of Radiology, Johns Hopkins University, Baltimore, MD 21287, United States
| | - Dean F Wong
- Department of Radiology, Johns Hopkins University, Baltimore, MD 21287, United States; Department of Psychiatry, Johns Hopkins University, Baltimore, MD 21287, United States; Department of Neuroscience, Johns Hopkins University, Baltimore, MD 21287, United States
| | - David A Lewis
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15213, United States; Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA 15213, United States
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59
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Draycott B, Loureiro M, Ahmad T, Tan H, Zunder J, Laviolette SR. Cannabinoid transmission in the prefrontal cortex bi-phasically controls emotional memory formation via functional interactions with the ventral tegmental area. J Neurosci 2014; 34:13096-109. [PMID: 25253856 PMCID: PMC6608340 DOI: 10.1523/jneurosci.1297-14.2014] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 08/15/2014] [Accepted: 08/15/2014] [Indexed: 01/01/2023] Open
Abstract
Disturbances in cortical cannabinoid CB1 receptor signaling are well established correlates of various neuropsychiatric disorders, including depression and schizophrenia. Importantly, the ability of cannabinoid transmission to modulate emotional processing is functionally linked to interactions with subcortical DA systems. While considerable evidence demonstrates that CB1 receptor-mediated modulation of emotional processing and related behaviors follows a biphasic functional curve, little is known regarding how CB1 signaling within cortical networks may interact with subcortical DAergic systems involved in emotional behavior regulation. Using a combination of in vivo electrophysiological recordings and behavioral pharmacology in rats, we investigated the relationship between mPFC cannabinoid transmission, fear memory formation, and subcortical DA neuron activity patterns. We report that direct intra-mPFC CB1 activation biphasically modulates spontaneous, subcortical VTA DA neuron activity in a dose-dependent fashion; while lower doses of a CB1 receptor agonist, WIN 55,212-2, significantly increased spontaneous firing and bursting rates of VTA DA neurons, higher doses strongly inhibited spontaneous DA neuron activity. Remarkably, this same dose-related functional difference was observed with the regulation of fear-related emotional memory formation. Thus, lower levels of CB1 activation potentiated the emotional salience of normally subthreshold fear memory, whereas higher levels completely blocked fear memory acquisition. Furthermore, while the potentiation of subthreshold fear memory salience was blocked by DA receptor antagonism, CB1-mediated blunting of suprathreshold fear memory was rescued by intra-VTA administration of a GABAB receptor antagonist, demonstrating that reversal of GABAergic inhibitory mechanisms in the VTA can reverse the inhibitory influence of intra-PFC CB1 transmission on mesolimbic DA activity.
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Affiliation(s)
| | - Michael Loureiro
- Addiction Research Group, Departments of Anatomy and Cell Biology
| | - Tasha Ahmad
- Addiction Research Group, Departments of Anatomy and Cell Biology
| | - Huibing Tan
- Addiction Research Group, Departments of Anatomy and Cell Biology
| | - Jordan Zunder
- Addiction Research Group, Departments of Anatomy and Cell Biology
| | - Steven R Laviolette
- Addiction Research Group, Departments of Anatomy and Cell Biology, Department of Psychiatry, and Department of Psychology, Schulich School of Medicine and Dentistry. University of Western Ontario, London, Ontario, Canada N6A 5C1
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60
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Bossong MG, Jansma JM, Bhattacharyya S, Ramsey NF. Role of the endocannabinoid system in brain functions relevant for schizophrenia: an overview of human challenge studies with cannabis or ∆9-tetrahydrocannabinol (THC). Prog Neuropsychopharmacol Biol Psychiatry 2014; 52:53-69. [PMID: 24380726 DOI: 10.1016/j.pnpbp.2013.11.017] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Revised: 10/16/2013] [Accepted: 11/25/2013] [Indexed: 12/30/2022]
Abstract
Accumulating evidence suggests involvement of the endocannabinoid system in the pathophysiology of schizophrenia, which signifies a potential application for this system in the treatment of this disorder. However, before new research can focus on potential treatments that work by manipulating the endocannabinoid system, it needs to be elucidated how this system is involved in symptoms of schizophrenia. Here we review human studies that investigated acute effects of cannabis or ∆9-tetrahydrocannabinol (THC) on brain functions that are implicated in schizophrenia. Results suggest that the impact of THC administration depends on the difficulty of the task performed. Impaired performance of cognitive paradigms is reported on more challenging tasks, which is associated with both activity deficits in temporal and prefrontal areas and a failure to deactivate regions of the default mode network. Comparable reductions in prefrontal activity and impairments in deactivation of the default mode network are seen in patients during performance of cognitive paradigms. Normal performance levels after THC administration demonstrated for less demanding tasks are shown to be related to either increased neural effort in task-specific regions ('neurophysiological inefficiency'), or recruitment of alternative brain areas, which suggests a change in strategy to meet cognitive demands. Particularly a pattern of performance and brain activity corresponding with an inefficient working memory system is consistently demonstrated in patients. These similarities in brain function between intoxicated healthy volunteers and schizophrenia patients provide an argument for a role of the endocannabinoid system in symptoms of schizophrenia, and further emphasize this system as a potential novel target for treatment of these symptoms.
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Affiliation(s)
- Matthijs G Bossong
- Institute of Psychiatry, Department of Psychosis Studies, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom.
| | - J Martijn Jansma
- Rudolf Magnus Institute of Neuroscience, Department of Neurology and Neurosurgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Sagnik Bhattacharyya
- Institute of Psychiatry, Department of Psychosis Studies, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom
| | - Nick F Ramsey
- Rudolf Magnus Institute of Neuroscience, Department of Neurology and Neurosurgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
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Ferretjans R, de Campos SM, Ribeiro-Santos R, Guimarães FC, de Oliveira K, Cardoso ACA, Araújo MS, Teixeira-Carvalho A, Martins-Filho OA, Teixeira AL, Salgado JV. Cognitive performance and peripheral endocannabinoid system receptor expression in schizophrenia. Schizophr Res 2014; 156:254-60. [PMID: 24853061 DOI: 10.1016/j.schres.2014.04.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Revised: 04/05/2014] [Accepted: 04/11/2014] [Indexed: 02/06/2023]
Abstract
Schizophrenia is a chronic psychiatric syndrome characterized by generalized cognitive deficits that are associated with functional impairment. The endocannabinoid system (ECS) modulates neurotransmission and neuronal plasticity and is important for cognitive functioning. Evidence points to the involvement of this neuromodulatory system in the pathophysiology of schizophrenia and that alteration of the ECS on peripheral lymphocytes could reflect central changes. The objective of this study was to compare levels of peripheral endocannabinoid receptor expression in patients with schizophrenia and healthy subjects and find evidence of association between peripheral expression of those receptors and cognitive performance. Patients with stabilized schizophrenia (N=53) and controls (N=22) underwent clinical and cognitive evaluation, and assessment of cannabinoid receptor expression on the surface of peripheral immune cells (lymphocytes, natural killer cells and monocytes) by flow cytometry. Patients with schizophrenia had lower levels of cannabinoid receptor expression on total T lymphocytes, but after controlling for possible confounders this difference did not remain significant. In patients, increased cannabinoid receptor expression on lymphocytes and monocytes was significantly correlated with worst cognitive performance. These data provide additional evidence of the involvement of the ECS in the pathophysiology of cognitive deficits in schizophrenia.
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Affiliation(s)
- Rodrigo Ferretjans
- Programa de Pós-graduação em Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), MG, Brazil; Hospital de Ensino Instituto Raul Soares, Fundação Hospitalar do Estado de Minas Gerais (FHEMIG), MG, Brazil.
| | - Salvina Maria de Campos
- Programa de Pós-graduação em Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), MG, Brazil; Hospital de Ensino Instituto Raul Soares, Fundação Hospitalar do Estado de Minas Gerais (FHEMIG), MG, Brazil
| | - Rafael Ribeiro-Santos
- Programa de Pós-graduação em Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), MG, Brazil; Hospital de Ensino Instituto Raul Soares, Fundação Hospitalar do Estado de Minas Gerais (FHEMIG), MG, Brazil
| | - Fernanda Carneiro Guimarães
- Programa de Pós-graduação em Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), MG, Brazil; Hospital de Ensino Instituto Raul Soares, Fundação Hospitalar do Estado de Minas Gerais (FHEMIG), MG, Brazil
| | - Keliane de Oliveira
- Programa de Pós-graduação em Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), MG, Brazil; Hospital de Ensino Instituto Raul Soares, Fundação Hospitalar do Estado de Minas Gerais (FHEMIG), MG, Brazil
| | - Ana Cecília Alves Cardoso
- Hospital de Ensino Instituto Raul Soares, Fundação Hospitalar do Estado de Minas Gerais (FHEMIG), MG, Brazil; Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), MG, Brazil
| | | | | | | | - Antonio L Teixeira
- Programa de Pós-graduação em Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), MG, Brazil; Laboratório Interdisciplinar de Investigação Médica, Faculdade de Medicina, Universidade Federal de Minas Gerais (UFMG), MG, Brazil
| | - João V Salgado
- Programa de Pós-graduação em Neurociências, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), MG, Brazil; Hospital de Ensino Instituto Raul Soares, Fundação Hospitalar do Estado de Minas Gerais (FHEMIG), MG, Brazil; Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), MG, Brazil.
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Verdurand M, Dalton VS, Nguyen V, Grégoire MC, Zahra D, Wyatt N, Burgess L, Greguric I, Zavitsanou K. Prenatal poly I:C age-dependently alters cannabinoid type 1 receptors in offspring: a longitudinal small animal PET study using [(18)F]MK-9470. Exp Neurol 2014; 257:162-9. [PMID: 24825369 DOI: 10.1016/j.expneurol.2014.05.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 04/28/2014] [Accepted: 05/05/2014] [Indexed: 01/13/2023]
Abstract
Evidence suggests that there is a link between the endocannabinoid system (ECS) and neuropsychiatric illnesses, including schizophrenia. Whilst the ECS has been shown to be involved in immune system regulation in various ways, it is known that infections during pregnancy can modulate the immune system of the mother and increase the risk for schizophrenia in offspring. In animal studies, maternal immune activation following administration of viral or bacterial mimics has been shown to reproduce many key structural, behavioural, and pharmacological abnormalities in offspring that resemble schizophrenia. In the present study, we used Positron Emission Tomography (PET) and [(18)F]MK-9470, a selective high-affinity inverse agonist radioligand for cannabinoid type 1 receptors (CB1R), to longitudinally assess CB1R expression in the progeny of female rats exposed to the viral mimic polyriboinosinic-polyribocytidilic acid (poly I:C) (4mg/kg i.v.) or vehicle at gestational day 15 (GD 15). PET scans were performed in offspring at postnatal days (PND) 32-42 (adolescence) and in the same animals again at PNDs 75-79 (adulthood). Sixteen regions of interest were assessed, encompassing the whole rat brain. At adolescence, offspring exposed prenatally to poly I:C had significantly lower CB1R relative Standard Uptake Values (rSUV) compared to controls in the globus pallidus (p=0.046). In adulthood, however, poly I:C exposed offspring had higher levels of CB1R rSUV in sensory cortex (p=0.034) and hypothalamus (p=0.032) compared to controls. Our results suggest that prenatal poly I:C leads to long term alterations in the integrity of the ECS that are age and region-specific. The increased CB1R expression in adulthood following poly I:C mirrors the increased CB1R observed in patients with schizophrenia in post-mortem and in vivo PET studies.
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Affiliation(s)
- Mathieu Verdurand
- Schizophrenia Research Institute, Sydney, Australia; ANSTO LifeSciences, ANSTO, PMB 1 Menai, NSW 2234, Australia; Neuroscience Research Center Lyon (CRNL, CNRS UMR5292, INSERM U1028), BioRaN Team, Lyon, France.
| | - Victoria S Dalton
- Schizophrenia Research Institute, Sydney, Australia; ANSTO LifeSciences, ANSTO, PMB 1 Menai, NSW 2234, Australia; Department of Psychiatry and Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.
| | - Vu Nguyen
- ANSTO LifeSciences, ANSTO, PMB 1 Menai, NSW 2234, Australia.
| | | | - David Zahra
- ANSTO LifeSciences, ANSTO, PMB 1 Menai, NSW 2234, Australia.
| | - Naomi Wyatt
- ANSTO LifeSciences, ANSTO, PMB 1 Menai, NSW 2234, Australia.
| | - Leena Burgess
- ANSTO LifeSciences, ANSTO, PMB 1 Menai, NSW 2234, Australia.
| | - Ivan Greguric
- ANSTO LifeSciences, ANSTO, PMB 1 Menai, NSW 2234, Australia.
| | - Katerina Zavitsanou
- Schizophrenia Research Institute, Sydney, Australia; ANSTO LifeSciences, ANSTO, PMB 1 Menai, NSW 2234, Australia; Neuroscience Research Australia, Randwick, NSW 2031, Australia; School of Psychiatry, Faculty of Medicine, University of New South Wales, Sydney, NSW 2052, Australia.
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Almeida V, Peres FF, Levin R, Suiama MA, Calzavara MB, Zuardi AW, Hallak JE, Crippa JA, Abílio VC. Effects of cannabinoid and vanilloid drugs on positive and negative-like symptoms on an animal model of schizophrenia: the SHR strain. Schizophr Res 2014; 153:150-9. [PMID: 24556469 DOI: 10.1016/j.schres.2014.01.039] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 01/14/2014] [Accepted: 01/16/2014] [Indexed: 02/06/2023]
Abstract
Studies have suggested that the endocannabinoid system is implicated in the pathophysiology of schizophrenia. We have recently reported that Spontaneously Hypertensive Rats (SHRs) present a deficit in social interaction that is ameliorated by atypical antipsychotics. In addition, SHRs display hyperlocomotion - reverted by atypical and typical antipsychotics. These results suggest that this strain could be useful to study negative symptoms (modeled by a decrease in social interaction) and positive symptoms (modeled by hyperlocomotion) of schizophrenia and the effects of potential drugs with an antipsychotic profile. The aim of this study was to investigate the effects of WIN55-212,2 (CB1/CB2 agonist), ACEA (CB1 agonist), rimonabant (CB1 inverse agonist), AM404 (anandamide uptake/metabolism inhibitor), capsaicin (agonist TRPV1) and capsazepine (antagonist TRPV1) on the social interaction and locomotion of control animals (Wistar rats) and SHRs. The treatment with rimonabant was not able to alter either the social interaction or the locomotion presented by Wistar rats (WR) and SHR at any dose tested. The treatment with WIN55-212,2 decreased locomotion (1mg/kg) and social interaction (0.1 and 0.3mg/kg) of WR, while the dose of 1mg/kg increased social interaction of SHR. The treatment with ACEA increased (0.3mg/kg) and decreased (1mg/kg) locomotion of both strain. The administration of AM404 increased social interaction and decreased locomotion of SHR (5mg/kg), and decreased social interaction and increased locomotion in WR (1mg/kg). The treatment with capsaicin (2.5mg/kg) increased social interaction of both strain and decreased locomotion of SHR (2.5mg/kg) and WR (0.5mg/kg and 2.5mg/kg). In addition, capsazepine (5mg/kg) decreased locomotion of both strains and increased (5mg/kg) and decreased (10mg/kg) social interaction of WR. Our results indicate that the schizophrenia-like behaviors displayed by SHR are differently altered by cannabinoid and vanilloid drugs when compared to control animals and suggest the endocannabinoid and the vanilloid systems as a potential target for the treatment of schizophrenia.
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Affiliation(s)
- Valéria Almeida
- Department of Pharmacology, Federal University of São Paulo, UNIFESP/EPM, Brazil; Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Department of Psychiatry, Federal University of São Paulo, UNIFESP/EPM, Brazil
| | - Fernanda F Peres
- Department of Pharmacology, Federal University of São Paulo, UNIFESP/EPM, Brazil; Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Department of Psychiatry, Federal University of São Paulo, UNIFESP/EPM, Brazil
| | - Raquel Levin
- Department of Pharmacology, Federal University of São Paulo, UNIFESP/EPM, Brazil; Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Department of Psychiatry, Federal University of São Paulo, UNIFESP/EPM, Brazil
| | - Mayra A Suiama
- Department of Pharmacology, Federal University of São Paulo, UNIFESP/EPM, Brazil; Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Department of Psychiatry, Federal University of São Paulo, UNIFESP/EPM, Brazil
| | - Mariana B Calzavara
- Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Department of Psychiatry, Federal University of São Paulo, UNIFESP/EPM, Brazil
| | - Antônio W Zuardi
- Department of Neuroscience and Behavior, University of São Paulo, Ribeirão Preto, Brazil; National Institute for Translational Medicine (INCT-TM, CNPq), Ribeirão Preto, Brazil
| | - Jaime E Hallak
- Department of Neuroscience and Behavior, University of São Paulo, Ribeirão Preto, Brazil; National Institute for Translational Medicine (INCT-TM, CNPq), Ribeirão Preto, Brazil
| | - José A Crippa
- Department of Neuroscience and Behavior, University of São Paulo, Ribeirão Preto, Brazil; National Institute for Translational Medicine (INCT-TM, CNPq), Ribeirão Preto, Brazil
| | - Vanessa C Abílio
- Department of Pharmacology, Federal University of São Paulo, UNIFESP/EPM, Brazil; Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Department of Psychiatry, Federal University of São Paulo, UNIFESP/EPM, Brazil.
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Levin R, Peres FF, Almeida V, Calzavara MB, Zuardi AW, Hallak JEC, Crippa JAS, Abílio VC. Effects of cannabinoid drugs on the deficit of prepulse inhibition of startle in an animal model of schizophrenia: the SHR strain. Front Pharmacol 2014; 5:10. [PMID: 24567721 PMCID: PMC3915876 DOI: 10.3389/fphar.2014.00010] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Accepted: 01/17/2014] [Indexed: 01/08/2023] Open
Abstract
Clinical and neurobiological findings suggest that the cannabinoids and the endocannabinoid system may be implicated in the pathophysiology and treatment of schizophrenia. We described that the spontaneously hypertensive rats (SHR) strain presents a schizophrenia behavioral phenotype that is specifically attenuated by antipsychotic drugs, and potentiated by proschizophrenia manipulations. Based on these findings, we have suggested this strain as an animal model of schizophrenia. The aim of this study was to evaluate the effects of cannabinoid drugs on the deficit of prepulse inhibition (PPI) of startle, the main paradigm used to study sensorimotor gating impairment related to schizophrenia, presented by the SHR strain. The following drugs were used: (1) WIN55212,2 (cannabinoid agonist), (2) rimonabant (CB1 antagonist), (3) AM404 (anandamide uptake inhibitor), and (4) cannabidiol (CBD; indirect CB1/CB2 receptor antagonist, among other effects). Wistar rats (WRs) and SHRs were treated with vehicle (VEH) or different doses of WIN55212 (0.3, 1, or 3 mg/kg), rimonabant (0.75, 1.5, or 3 mg/kg), AM404 (1, 5, or 10 mg/kg), or CBD (15, 30, or 60 mg/kg). VEH-treated SHRs showed a decreased PPI when compared to WRs. This PPI deficit was reversed by 1 mg/kg WIN and 30 mg/kg CBD. Conversely, 0.75 mg/kg rimonabant decreased PPI in SHR strain, whereas AM404 did not modify it. Our results reinforce the role of the endocannabinoid system in the sensorimotor gating impairment related to schizophrenia, and point to cannabinoid drugs as potential therapeutic strategies.
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Affiliation(s)
- Raquel Levin
- Department of Pharmacology, Federal University of São PauloSão Paulo, Brazil
- Laboratório Interdisciplinar de Neurociãncias Clínicas, Department of Psychiatry, Federal University of São PauloSão Paulo, Brazil
| | - Fernanda F. Peres
- Department of Pharmacology, Federal University of São PauloSão Paulo, Brazil
- Laboratório Interdisciplinar de Neurociãncias Clínicas, Department of Psychiatry, Federal University of São PauloSão Paulo, Brazil
| | - Valéria Almeida
- Department of Pharmacology, Federal University of São PauloSão Paulo, Brazil
- Laboratório Interdisciplinar de Neurociãncias Clínicas, Department of Psychiatry, Federal University of São PauloSão Paulo, Brazil
| | - Mariana B. Calzavara
- Laboratório Interdisciplinar de Neurociãncias Clínicas, Department of Psychiatry, Federal University of São PauloSão Paulo, Brazil
| | - Antonio W. Zuardi
- Department of Neuroscience and Behavior, University of São PauloRibeirão Preto, Brazil
- National Institute of Science and Technology in Translational Medicine, National Council for Scientific and Technological DevelopmentRibeirão Preto, Brazil
| | - Jaime E. C. Hallak
- Department of Neuroscience and Behavior, University of São PauloRibeirão Preto, Brazil
- National Institute of Science and Technology in Translational Medicine, National Council for Scientific and Technological DevelopmentRibeirão Preto, Brazil
| | - José Alexandre S. Crippa
- Department of Neuroscience and Behavior, University of São PauloRibeirão Preto, Brazil
- National Institute of Science and Technology in Translational Medicine, National Council for Scientific and Technological DevelopmentRibeirão Preto, Brazil
| | - Vanessa C. Abílio
- Department of Pharmacology, Federal University of São PauloSão Paulo, Brazil
- Laboratório Interdisciplinar de Neurociãncias Clínicas, Department of Psychiatry, Federal University of São PauloSão Paulo, Brazil
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Zuardi AW, Guimarães FS, Hallak JEC, Crippa JAS. Is the highest density of CB1 receptors in paranoid schizophrenia a correlate of endocannabinoid system functioning? Expert Rev Neurother 2014; 11:1111-4. [DOI: 10.1586/ern.11.89] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Tan H, Ahmad T, Loureiro M, Zunder J, Laviolette SR. The role of cannabinoid transmission in emotional memory formation: implications for addiction and schizophrenia. Front Psychiatry 2014; 5:73. [PMID: 25071606 PMCID: PMC4074769 DOI: 10.3389/fpsyt.2014.00073] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 06/13/2014] [Indexed: 11/26/2022] Open
Abstract
Emerging evidence from both basic and clinical research demonstrates an important role for endocannabinoid (ECB) signaling in the processing of emotionally salient information, learning, and memory. Cannabinoid transmission within neural circuits involved in emotional processing has been shown to modulate the acquisition, recall, and extinction of emotionally salient memories and importantly, can strongly modulate the emotional salience of incoming sensory information. Two neural regions in particular, the medial prefrontal cortex (PFC) and the basolateral nucleus of the amygdala (BLA), play important roles in emotional regulation and contain high levels of cannabinoid receptors. Furthermore, both regions show profound abnormalities in neuropsychiatric disorders such as addiction and schizophrenia. Considerable evidence has demonstrated that cannabinoid transmission functionally interacts with dopamine (DA), a neurotransmitter system that is of exceptional importance for both addictive behaviors and the neuropsychopathology of disorders like schizophrenia. Research in our laboratory has focused on how cannabinoid transmission both within and extrinsic to the mesolimbic DA system, including the BLA → mPFC circuitry, can modulate both rewarding and aversive emotional information. In this review, we will summarize clinical and basic neuroscience research demonstrating the importance of cannabinoid signaling within this neural circuitry. In particular, evidence will be reviewed emphasizing the importance of cannabinoid signaling within the BLA → mPFC circuitry in the context of emotional salience processing, memory formation and memory-related plasticity. We propose that aberrant states of hyper or hypoactive ECB signaling within the amygdala-prefrontal cortical circuit may lead to dysregulation of mesocorticolimbic DA transmission controlling the processing of emotionally salient information. These disturbances may in turn lead to emotional processing, learning, and memory abnormalities related to various neuropsychiatric disorders, including addiction and schizophrenia-related psychoses.
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Affiliation(s)
- Huibing Tan
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario , London, ON , Canada
| | - Tasha Ahmad
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario , London, ON , Canada
| | - Michael Loureiro
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario , London, ON , Canada
| | - Jordan Zunder
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario , London, ON , Canada
| | - Steven R Laviolette
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario , London, ON , Canada ; Department of Psychiatry, Schulich School of Medicine and Dentistry, University of Western Ontario , London, ON , Canada ; Department of Psychology, Schulich School of Medicine and Dentistry, University of Western Ontario , London, ON , Canada
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Schubart CD, Sommer IEC, Fusar-Poli P, de Witte L, Kahn RS, Boks MPM. Cannabidiol as a potential treatment for psychosis. Eur Neuropsychopharmacol 2014; 24:51-64. [PMID: 24309088 DOI: 10.1016/j.euroneuro.2013.11.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 11/05/2013] [Accepted: 11/09/2013] [Indexed: 12/18/2022]
Abstract
Although cannabis use is associated with an increased risk of developing psychosis, the cannabis constituent cannabidiol (CBD) may have antipsychotic properties. This review concisely describes the role of the endocannabinoid system in the development of psychosis and provides an overview of currently available animal, human experimental, imaging, epidemiological and clinical studies that investigated the antipsychotic properties of CBD. In this targeted literature review we performed a search for English articles using Medline and EMBASE. Studies were selected if they described experiments with psychosis models, psychotic symptoms or psychotic disorders as outcome measure and involved the use of CBD as intervention. Evidence from several research domains suggests that CBD shows potential for antipsychotic treatment.
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Affiliation(s)
- C D Schubart
- Tergooi Hospital, Department of Psychiatry, Blaricum, The Netherlands
| | - I E C Sommer
- Brain Center Rudolf Magnus, University Medical Centre Utrecht, Department of Psychiatry, The Netherlands
| | - P Fusar-Poli
- Department of Psychosis Studies, Institute of Psychiatry, King's College London, UK
| | - L de Witte
- Brain Center Rudolf Magnus, University Medical Centre Utrecht, Department of Psychiatry, The Netherlands
| | - R S Kahn
- Tergooi Hospital, Department of Psychiatry, Blaricum, The Netherlands
| | - M P M Boks
- Brain Center Rudolf Magnus, University Medical Centre Utrecht, Department of Psychiatry, The Netherlands.
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Ceccarini J, De Hert M, Van Winkel R, Peuskens J, Bormans G, Kranaster L, Enning F, Koethe D, Leweke FM, Van Laere K. Increased ventral striatal CB1 receptor binding is related to negative symptoms in drug-free patients with schizophrenia. Neuroimage 2013; 79:304-12. [DOI: 10.1016/j.neuroimage.2013.04.052] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 03/26/2013] [Accepted: 04/15/2013] [Indexed: 11/16/2022] Open
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Quantification of endocannabinoids in postmortem brain of schizophrenic subjects. Schizophr Res 2013; 148:145-50. [PMID: 23800614 DOI: 10.1016/j.schres.2013.06.013] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 05/14/2013] [Accepted: 06/02/2013] [Indexed: 11/24/2022]
Abstract
Numerous studies have implicated the endocannabinoid system in the pathophysiology of schizophrenia. Endocannabinoids have been measured in blood and cerebrospinal fluid in schizophrenic patients but, to the date, there are no published reports dealing with measurements of endocannabinoid levels in schizophrenics' brain tissue. In the present study, postmortem brain samples from 19 subjects diagnosed with schizophrenia (DSM-IV) and 19 matched controls were studied. In specific brain regions, levels of four endocannabinoids (2-arachidonoylglycerol (2-AG), arachidonoylethanolamine (anandamide, AEA), dihomo-γ-linolenoylethanolamine (LEA), and docosahexaenoylethanolamine (DHEA)) and two cannabimimetic compounds (palmitoyl-ethanolamine (PEA) and oleoyl-ethanolamine (OEA)) were measured using quantitative liquid chromatography with triple quadrupole mass spectrometric detection. Suffering from schizophrenia significantly affects the brain levels of 2-AG (p<0.001), AEA (p<0.0001), DHEA (p<0.0001), LEA (p<0.01) and PEA (p<0.05). In schizophrenic subjects, the three studied brain regions (cerebellum: 130±18%; p=0.16; hippocampus: 168±28%, p<0.01; prefrontal cortex: 237±45%, p<0.05) showed higher 2-AG levels when compared to matched controls. Conversely, AEA levels were lower in all brain regions of schizophrenic subjects (cerebellum: 66±7%, p<0.01; hippocampus: 66±7%, p<0.01; prefrontal cortex: 75±10%, p=0.07). Statistically significant lower levels of DHEA were also found in cerebellum (60±6%, p<0.001) and hippocampus (68±7%, p<0.05) of schizophrenic subjects. PEA (71±6%, p<0.05) and LEA (72±6%, p<0.05) levels were also found to be lower in cerebellum. No significant differences were found in OEA levels. Our results evidence specific alterations in the levels of some endocannabinoids in different brain regions of schizophrenic subjects. Furthermore, these data evidence the involvement of the endocannabinoid system in the pathophysiology of schizophrenia.
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Seillier A, Martinez AA, Giuffrida A. Phencyclidine-induced social withdrawal results from deficient stimulation of cannabinoid CB₁ receptors: implications for schizophrenia. Neuropsychopharmacology 2013; 38:1816-24. [PMID: 23563893 PMCID: PMC3717536 DOI: 10.1038/npp.2013.81] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 03/06/2013] [Accepted: 03/24/2013] [Indexed: 01/02/2023]
Abstract
The neuronal mechanisms underlying social withdrawal, one of the core negative symptoms of schizophrenia, are not well understood. Recent studies suggest an involvement of the endocannabinoid system in the pathophysiology of schizophrenia and, in particular, of negative symptoms. We used biochemical, pharmacological, and behavioral approaches to investigate the role played by the endocannabinoid system in social withdrawal induced by sub-chronic administration of phencyclidine (PCP). Pharmacological enhancement of endocannabinoid levels via systemic administration of URB597, an inhibitor of endocannabinoid degradation, reversed social withdrawal in PCP-treated rats via stimulation of CB1 receptors, but reduced social interaction in control animals through activation of a cannabinoid/vanilloid-sensitive receptor. In addition, the potent CB agonist CP55,940 reversed PCP-induced social withdrawal in a CB₁-dependent manner, whereas pharmacological blockade of CB₁ receptors by either AM251 or SR141716 reduced the time spent in social interaction in control animals. PCP-induced social withdrawal was accompanied by a decrease of anandamide (AEA) levels in the amygdala and prefrontal cortex, and these deficits were reversed by URB597. As CB₁ receptors are predominantly expressed on GABAergic interneurons containing the anxiogenic peptide cholecystokinin (CCK), we also examined whether the PCP-induced social withdrawal resulted from deficient CB₁-mediated modulation of CCK transmission. The selective CCK2 antagonist LY225910 blocked both PCP- and AM251-induced social withdrawal, but not URB597 effect in control rats. Taken together, these findings indicate that AEA-mediated activation of CB₁ receptors is crucial for social interaction, and that PCP-induced social withdrawal results from deficient endocannabinoid transmission.
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Affiliation(s)
- Alexandre Seillier
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA.
| | - Alex A Martinez
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX , USA
| | - Andrea Giuffrida
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX , USA
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Parakh P, Basu D. Cannabis and psychosis: have we found the missing links? Asian J Psychiatr 2013; 6:281-7. [PMID: 23810133 DOI: 10.1016/j.ajp.2013.03.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2012] [Revised: 03/10/2013] [Accepted: 03/30/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND The association between cannabis and psychosis has long been a matter of debate, with cannabis widely perceived as a harmless recreational drug. METHODS Electronic bibliographic databases like PubMed and Google Scholar were searched using the format "(psychosis or schizophrenia or synonyms) and (cannabis or synonyms)". Cross-linked searches were made taking the lead from key articles. Recent articles and those exploring the genetic factors or gene-environment interaction between cannabis use and psychosis were focussed upon. RESULTS Heavy cannabis use at a n young age, in association with genetic liability to psychosis and exposure to environmental stressors like childhood trauma and urban upbringing increases the risk of psychotic outcome in later life. CONCLUSION Cannabis acts as a component cause of psychosis, that is, it increases the risk of psychosis in people with certain genetic or environmental vulnerabilities, though by itself, it is neither a sufficient nor a necessary cause of psychosis. Although significant progress has been made over the last few years, we are yet to find all the missing links. Further work is necessary to identify all the factors that underlie individual vulnerability to cannabis-related psychosis and to elucidate the biological mechanisms underlying this risk.
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Affiliation(s)
- Preeti Parakh
- Department of Psychiatry, Postgraduate Institute of Medical Education & Research, Chandigarh 160012, India.
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Costa M, Squassina A, Congiu D, Chillotti C, Niola P, Galderisi S, Pistis M, Del Zompo M. Investigation of endocannabinoid system genes suggests association between peroxisome proliferator activator receptor-α gene (PPARA) and schizophrenia. Eur Neuropsychopharmacol 2013; 23:749-59. [PMID: 22920733 DOI: 10.1016/j.euroneuro.2012.07.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 06/18/2012] [Accepted: 07/13/2012] [Indexed: 10/28/2022]
Abstract
Schizophrenia (SZ) is a complex psychiatric disorder with a large genetic burden and an estimated hereditability of 80%. A large number of neuroanatomical and psychopharmacological studies suggest a central role of the endocannabinoid (eCB) system in the susceptibility of the disease. To further investigate this hypothesis, we performed an association study with genes codifying for key elements of the eCB system in a sample of 170 schizophrenic patients and 350 healthy controls of Italian ancestry. A total of 57 Tag SNPs (tSNPs) were selected using HapMap CEU population SNP database spanning the following genes: cannabinoid receptor 1 (CNR1), peroxisome proliferator activator receptor-α (PPARA), fatty acid amide hydrolase (FAAH) and N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD). Seven out of the 32 tSNPs within PPARA (rs4253765, rs4263776, rs6007662, rs1800206, rs4253763, rs6008197 and rs4253655) and 3 out of 12 tSNPs within CNR1 (rs1049353, rs7766029 and rs806366) were nominally associated with SZ (uncorrected p<0.05). The same pattern of association was observed in the genotype analysis, with rs4253765 showing the highest level of significance (uncorrected p=2×10(-3)). None of these associations survived after permutation test. Our findings suggest a potential role for PPARA in the susceptibility to SZ, but further studies on larger independent samples are warranted in order to clarify the involvement of this gene in the pathophysiology of SZ.
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Affiliation(s)
- Marta Costa
- Section of Neurosciences and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
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Catts VS, Fung SJ, Long LE, Joshi D, Vercammen A, Allen KM, Fillman SG, Rothmond DA, Sinclair D, Tiwari Y, Tsai SY, Weickert TW, Shannon Weickert C. Rethinking schizophrenia in the context of normal neurodevelopment. Front Cell Neurosci 2013; 7:60. [PMID: 23720610 PMCID: PMC3654207 DOI: 10.3389/fncel.2013.00060] [Citation(s) in RCA: 144] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 04/16/2013] [Indexed: 01/11/2023] Open
Abstract
The schizophrenia brain is differentiated from the normal brain by subtle changes, with significant overlap in measures between normal and disease states. For the past 25 years, schizophrenia has increasingly been considered a neurodevelopmental disorder. This frame of reference challenges biological researchers to consider how pathological changes identified in adult brain tissue can be accounted for by aberrant developmental processes occurring during fetal, childhood, or adolescent periods. To place schizophrenia neuropathology in a neurodevelopmental context requires solid, scrutinized evidence of changes occurring during normal development of the human brain, particularly in the cortex; however, too often data on normative developmental change are selectively referenced. This paper focuses on the development of the prefrontal cortex and charts major molecular, cellular, and behavioral events on a similar time line. We first consider the time at which human cognitive abilities such as selective attention, working memory, and inhibitory control mature, emphasizing that attainment of full adult potential is a process requiring decades. We review the timing of neurogenesis, neuronal migration, white matter changes (myelination), and synapse development. We consider how molecular changes in neurotransmitter signaling pathways are altered throughout life and how they may be concomitant with cellular and cognitive changes. We end with a consideration of how the response to drugs of abuse changes with age. We conclude that the concepts around the timing of cortical neuronal migration, interneuron maturation, and synaptic regression in humans may need revision and include greater emphasis on the protracted and dynamic changes occurring in adolescence. Updating our current understanding of post-natal neurodevelopment should aid researchers in interpreting gray matter changes and derailed neurodevelopmental processes that could underlie emergence of psychosis.
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Affiliation(s)
- Vibeke S. Catts
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Samantha J. Fung
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Leonora E. Long
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Medical Sciences, University of New South WalesSydney, NSW, Australia
| | - Dipesh Joshi
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Ans Vercammen
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
- School of Psychology, Australian Catholic UniversitySydney, NSW, Australia
| | - Katherine M. Allen
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Stu G. Fillman
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Debora A. Rothmond
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
| | - Duncan Sinclair
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Yash Tiwari
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Medical Sciences, University of New South WalesSydney, NSW, Australia
| | - Shan-Yuan Tsai
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Thomas W. Weickert
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
| | - Cynthia Shannon Weickert
- Schizophrenia Research Laboratory, Schizophrenia Research InstituteSydney, NSW, Australia
- Neuroscience Research AustraliaSydney, NSW, Australia
- School of Psychiatry, University of New South WalesSydney, NSW, Australia
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Zamberletti E, Piscitelli F, Cadeddu F, Rubino T, Fratta W, Fadda P, Di Marzo V, Parolaro D. Chronic blockade of CB(1) receptors reverses startle gating deficits and associated neurochemical alterations in rats reared in isolation. Br J Pharmacol 2013; 167:1652-64. [PMID: 22762735 DOI: 10.1111/j.1476-5381.2012.02095.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Pharmacological interventions aimed at restoring the endocannabinoid system functionality have been proposed as potential tools in the treatment of schizophrenia. Based on our previous results suggesting a potential antipsychotic-like profile of the CB(1) receptor inverse agonist/antagonist, AM251, here we further investigated the effect of chronic AM251 administration on the alteration of the sensorimotor gating functions and endocannabinoid levels induced by isolation rearing in rats. EXPERIMENTAL APPROACH Using the post-weaning social isolation rearing model, we studied its influence on sensorimotor gating functions through the PPI paradigm. The presence of alterations in the endocannabinoid levels as well as in dopamine and glutamate receptor densities was explored in specific brain regions following isolation rearing. The effect of chronic AM251 administration on PPI response and the associated biochemical alterations was assessed. KEY RESULTS The disrupted PPI response in isolation-reared rats was paralleled by significant alterations in 2-AG content and dopamine and glutamate receptor densities in specific brain regions. Chronic AM251 completely restored normal PPI response in isolated rats. This behavioural recovery was paralleled by the normalization of 2-AG levels in all the brain areas analysed. Furthermore, AM251 partially antagonized isolation-induced changes in dopamine and glutamate receptors. CONCLUSIONS AND IMPLICATIONS These results demonstrate the efficacy of chronic AM251 treatment in the recovery of isolation-induced disruption of PPI. Moreover, AM251 counteracted the imbalances in the endocannabinoid content, specifically 2-AG levels, and partially reversed the alterations in dopamine and glutamate systems associated with the disrupted behaviour. Together, these findings support the potential antipsychotic-like activity of CB(1) receptor blockade. LINKED ARTICLES This article is part of a themed section on Cannabinoids. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.167.issue-8.
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Affiliation(s)
- E Zamberletti
- Department of Theoretical and Applied Sciences, Biomedical Division and Center of Neuroscience, University of Insubria, Busto Arsizio (VA), Italy
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Zavitsanou K, Dalton VS, Walker AK, Weickert CS, Sominsky L, Hodgson DM. Neonatal lipopolysaccharide treatment has long-term effects on monoaminergic and cannabinoid receptors in the rat. Synapse 2013; 67:290-9. [DOI: 10.1002/syn.21640] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 01/29/2013] [Indexed: 12/20/2022]
Affiliation(s)
| | - Victoria S. Dalton
- Department of Psychiatry and Trinity College Institute of Neuroscience; Trinity College Dublin; Dublin; Ireland
| | | | | | - Luba Sominsky
- Laboratory of Neuroimmunology, School of Psychology; University of Newcastle; Newcastle; Australia
| | - Deborah M. Hodgson
- Laboratory of Neuroimmunology, School of Psychology; University of Newcastle; Newcastle; Australia
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Transmembrane domain Nrg1 mutant mice show altered susceptibility to the neurobehavioural actions of repeated THC exposure in adolescence. Int J Neuropsychopharmacol 2013; 16:163-75. [PMID: 22226049 DOI: 10.1017/s1461145711001854] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Heavy cannabis abuse increases the risk of developing schizophrenia. Adolescents appear particularly vulnerable to the development of psychosis-like symptoms after cannabis use. To test whether the schizophrenia candidate gene neuregulin 1 (NRG1) modulates the effects of cannabinoids in adolescence, we tested male adolescent heterozygous transmembrane domain Nrg1 mutant (Nrg1 TM HET) mice and wild type-like littermates (WT) for their neurobehavioural response to repeated Δ(9)-tetrahydrocannabinol (THC, 10 mg/kg i.p. for 21 d starting on post-natal day 31). During treatment and 48 h after treatment withdrawal, we assessed several behavioural parameters relevant to schizophrenia. After behavioural testing we measured autoradiographic CB(1), 5-HT(2A) and NMDA receptor binding. The hyperlocomotor phenotype typical of Nrg1 mutants emerged after drug withdrawal and was more pronounced in vehicle than THC-treated Nrg1 TM HET mice. All mice were equally sensitive to THC-induced suppression of locomotion. However, mutant mice appeared protected against inhibiting effects of repeated THC on investigative social behaviours. Neither THC nor Nrg1 genotype altered prepulse inhibition. Repeated adolescent THC promoted differential effects on CB(1) and 5-HT(2A) receptor binding in the substantia nigra and insular cortex respectively, decreasing binding in WT while increasing it in Nrg1 TM HET mice. THC also selectively affected 5-HT(2A) receptor binding in several other regions in WT mice, whereas NMDA receptor binding was only affected in mutant mice. Overall, Nrg1 mutation does not appear to increase the induction of psychotomimetic symptoms by repeated adolescent THC exposure but may attenuate some of its actions on social behaviour and schizophrenia-relevant neurotransmitter receptor profiles.
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Binding of a tritiated inverse agonist to cannabinoid CB1 receptors is increased in patients with schizophrenia. Schizophr Res 2012; 141:185-8. [PMID: 22910406 PMCID: PMC3463751 DOI: 10.1016/j.schres.2012.07.021] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 07/16/2012] [Accepted: 07/18/2012] [Indexed: 01/04/2023]
Abstract
This study sought to determine whether cannabinoid-1 (CB(1)) receptor binding was altered in the postmortem dorsolateral prefrontal cortex (DLPFC) of individuals with schizophrenia (schizophrenia; n=47) compared to controls (n=43). The CB(1) receptor inverse agonist radioligand [(3)H]MePPEP was used to measure specific binding to CB(1) receptors. The specific binding of [(3)H]MePPEP to CB(1) receptors was 20% higher in patients with schizophrenia than in controls. Power analyses suggested that 53 subjects per group would be needed to detect a similar difference in vivo with positron emission tomography (PET) and the structurally related inverse agonist radioligand [(18)F]FMPEP-d(2) (80% statistical power, p<0.05).
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78
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Kleinloog D, Liem-Moolenaar M, Jacobs G, Klaassen E, de Kam M, Hijman R, van Gerven J. Does olanzapine inhibit the psychomimetic effects of Δ⁹-tetrahydrocannabinol? J Psychopharmacol 2012; 26:1307-16. [PMID: 22596206 DOI: 10.1177/0269881112446534] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Δ⁹-Tetrahydrocannabinol (THC) produces transient psychomimetic effects in healthy volunteers, constituting a pharmacological model for psychosis. The dopaminergic antagonist haloperidol has previously been shown to reduce these effects. This placebo-controlled, cross-over study in 49 healthy, male, mild cannabis users aimed to further explore this model by examining the effect of a single oral dose of olanzapine (with dopaminergic, serotonergic, adrenergic, muscarinergic and histaminergic properties) or two oral doses of diphenhydramine (histamine antagonist) on the effects of intrapulmonarily administered THC. Transient psychomimetic symptoms were seen after THC administration, as measured on the positive and negative syndrome scale (20.6% increase on positive subscale, p<0.001) and the visual analogue scale for psychedelic effects (increase of 10.7 mm on feeling high). Following the combination of THC and olanzapine, the positive subscale increased by only 13.7% and feeling high by only 8.7 mm. This reduction of THC effects on the positive subscale failed to reach statistical significance (p=0.066). However, one-third of the subjects did not show an increase in psychomimetic symptoms after THC alone. Within responders, olanzapine reduced the effects of THC on the positive subscale (p=0.005). Other outcome measures included pharmacokinetics, eye movements, postural stability, pupil/iris ratio, and serum concentrations of cortisol and prolactin.
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The Endocannabinoid System and its Role in Schizophrenia: A Systematic Review of the Literature. BRAZILIAN JOURNAL OF PSYCHIATRY 2012; 34 Suppl 2:S163-77. [DOI: 10.1016/j.rbp.2012.07.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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New insights on endocannabinoid transmission in psychomotor disorders. Prog Neuropsychopharmacol Biol Psychiatry 2012; 38:51-8. [PMID: 22521335 PMCID: PMC3389227 DOI: 10.1016/j.pnpbp.2012.04.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 03/26/2012] [Accepted: 04/01/2012] [Indexed: 11/21/2022]
Abstract
The endocannabinoids are lipid signaling molecules that bind to cannabinoid CB(1) and CB(2) receptors and other metabotropic and ionotropic receptors. Anandamide and 2-arachidonoyl glycerol, the two best-characterized examples, are released on demand in a stimulus-dependent manner by cleavage of membrane phospholipid precursors. Together with their receptors and metabolic enzymes, the endocannabinoids play a key role in modulating neurotransmission and synaptic plasticity in the basal ganglia and other brain areas involved in the control of motor functions and motivational aspects of behavior. This mini-review provides an update on the contribution of the endocannabinoid system to the regulation of psychomotor behaviors and its possible involvement in the pathophysiology of Parkinson's disease and schizophrenia.
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Bossong MG, Jansma JM, van Hell HH, Jager G, Oudman E, Saliasi E, Kahn RS, Ramsey NF. Effects of δ9-tetrahydrocannabinol on human working memory function. Biol Psychiatry 2012; 71:693-9. [PMID: 22341370 DOI: 10.1016/j.biopsych.2012.01.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Revised: 12/23/2011] [Accepted: 01/12/2012] [Indexed: 01/17/2023]
Abstract
BACKGROUND Evidence indicates involvement of the endocannabinoid (eCB) system in both the pathophysiology of schizophrenia and working memory (WM) function. Additionally, schizophrenia patients exhibit relatively strong WM deficits. These findings suggest the possibility that the eCB system is also involved in WM deficits in schizophrenia. In the present study, we examined if perturbation of the eCB system can induce abnormal WM activity in healthy subjects. METHODS A pharmacological functional magnetic resonance imaging study was conducted with a placebo-controlled, cross-over design, investigating effects of the eCB agonist Δ9-tetrahydrocannabinol on WM function in 17 healthy volunteers, by means of a parametric Sternberg item-recognition paradigm with five difficulty levels. RESULTS Performance accuracy was significantly reduced after Δ9-tetrahydrocannabinol. In the placebo condition, brain activity increased linearly with rising WM load. Δ9-Tetrahydrocannabinol administration enhanced activity for low WM loads and reduced the linear relationship between WM load and activity in the WM system as a whole and in left dorsolateral prefrontal cortex, inferior temporal gyrus, inferior parietal gyrus, and cerebellum in particular. CONCLUSIONS Δ9-Tetrahydrocannabinol enhanced WM activity network-wide for low loads, while reducing the load-dependent response for increasing WM loads. These results indicate that a challenged eCB system can induce both abnormal WM activity and WM performance deficits and provide an argument for the possibility of eCB involvement in WM deficits in schizophrenia.
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Affiliation(s)
- Matthijs G Bossong
- Department of Neurology and Neurosurgery, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Heidelberglaan 100, Utrecht, The Netherlands
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Rapp C, Bugra H, Riecher-Rössler A, Tamagni C, Borgwardt S. Effects of cannabis use on human brain structure in psychosis: a systematic review combining in vivo structural neuroimaging and post mortem studies. Curr Pharm Des 2012; 18:5070-80. [PMID: 22716152 PMCID: PMC3474956 DOI: 10.2174/138161212802884861] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 04/12/2012] [Indexed: 11/22/2022]
Abstract
It is unclear yet whether cannabis use is a moderating or causal factor contributing to grey matter alterations in schizophrenia and the development of psychotic symptoms. We therefore systematically reviewed structural brain imaging and post mortem studies addressing the effects of cannabis use on brain structure in psychosis. Studies with schizophrenia (SCZ) and first episode psychosis (FEP) patients as well as individuals at genetic (GHR) or clinical high risk for psychosis (ARMS) were included. We identified 15 structural magnetic resonance imaging (MRI) (12 cross sectional / 3 longitudinal) and 4 post mortem studies. The total number of subjects encompassed 601 schizophrenia or first episode psychosis patients, 255 individuals at clinical or genetic high risk for psychosis and 397 healthy controls. We found evidence for consistent brain structural abnormalities in cannabinoid 1 (CB1) receptor enhanced brain areas as the cingulate and prefrontal cortices and the cerebellum. As these effects have not consistently been reported in studies examining nonpsychotic and healthy samples, psychosis patients and subjects at risk for psychosis might be particularly vulnerable to brain volume loss due to cannabis exposure.
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Affiliation(s)
- Charlotte Rapp
- Department of Psychiatry, University of Basel, 4031 Basel, Switzerland
| | - Hilal Bugra
- Department of Psychiatry, University of Basel, 4031 Basel, Switzerland
| | | | - Corinne Tamagni
- Department of Psychiatry, University of Basel, 4031 Basel, Switzerland
| | - Stefan Borgwardt
- Department of Psychiatry, University of Basel, 4031 Basel, Switzerland
- Medical Image Analysis Centre, University of Basel, Switzerland
- King’s College London, Department of Psychosis Studies, De Crespigny Park, London SE5 8AF, United Kingdom
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Verdurand M, Nguyen V, Stark D, Zahra D, Gregoire MC, Greguric I, Zavitsanou K. Comparison of Cannabinoid CB(1) Receptor Binding in Adolescent and Adult Rats: A Positron Emission Tomography Study Using [F]MK-9470. INTERNATIONAL JOURNAL OF MOLECULAR IMAGING 2011; 2011:548123. [PMID: 22187642 PMCID: PMC3236487 DOI: 10.1155/2011/548123] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 09/17/2011] [Indexed: 12/14/2022]
Abstract
Despite the important role of cannabinoid CB(1) receptors (CB(1)R) in brain development, little is known about their status during adolescence, a critical period for both the development of psychosis and for initiation to substance abuse. In the present study, we assessed the ontogeny of CB(1)R in adolescent and adult rats in vivo using positron emission tomography with [(18)F]MK-9470. Analysis of covariance (ANCOVA) to control for body weight that would potentially influence [(18)F]MK-9470 values between the two groups revealed a main effect of age (F(1,109)=5.0, P = 0.02) on [(18)F]MK-9470 absolute binding (calculated as percentage of injected dose) with adult estimated marginal means being higher compared to adolescents amongst 11 brain regions. This finding was confirmed using in vitro autoradiography with [(3)H]CP55,940 (F(10,99)=140.1, P < 0.0001). This ontogenetic pattern, suggesting increase of CB(1)R during the transition from adolescence to adulthood, is the opposite of most other neuroreceptor systems undergoing pruning during this period.
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Affiliation(s)
- Mathieu Verdurand
- Schizophrenia Research Institute, Sydney, Australia
- ANSTO LifeSciences, ANSTO, PMB 1 Menai, Sydney, Australia
| | - Vu Nguyen
- ANSTO LifeSciences, ANSTO, PMB 1 Menai, Sydney, Australia
| | - Daniela Stark
- ANSTO LifeSciences, ANSTO, PMB 1 Menai, Sydney, Australia
| | - David Zahra
- ANSTO LifeSciences, ANSTO, PMB 1 Menai, Sydney, Australia
| | | | - Ivan Greguric
- ANSTO LifeSciences, ANSTO, PMB 1 Menai, Sydney, Australia
| | - Katerina Zavitsanou
- Schizophrenia Research Institute, Sydney, Australia
- School of Psychiatry, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
- Schizophrenia Research Laboratory, Neuroscience Research Australia, Randwick, NSW, Australia
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