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Marusak HA, Evanski J, Desai S, Rabinak CA. Impact of Childhood Trauma Exposure, Genetic Variation in Endocannabinoid Signaling, and Anxiety on Frontolimbic Pathways in Children. Cannabis Cannabinoid Res 2023; 8:1079-1089. [PMID: 35944262 PMCID: PMC10714120 DOI: 10.1089/can.2022.0144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Introduction: The endocannabinoid (eCB) system plays a key role in modulating brain development, including myelination processes. Recent studies link a common variant (C385A, rs324420) in the fatty acid amide hydrolase (FAAH) gene to higher circulating eCB levels, lower anxiety, and altered frontolimbic development. Frontolimbic pathways, which demonstrate a protracted maturational course across childhood and adolescence, are associated with anxiety, and are vulnerable to environmental stressors such as trauma exposure. Here, we examined the impact of trauma exposure, FAAH genotype, and anxiety on frontolimbic white matter microstructure in children. Materials and Methods: We leveraged baseline data from the Adolescent Brain Cognitive Development (ABCD) study (n=9969; mean±standard deviation age=9.92±0.62 years; 47.1% female). Saliva samples were used for genotyping, and caregivers reported on their child's anxiety symptoms and trauma exposure. Fractional anisotropy (FA), a nonspecific measure of white matter integrity, was estimated for frontolimbic tracts. Results: Thirty-six percent of youth experienced one or more potentially traumatic events according to DSM-5 Criterion A (64% controls), and 45% were FAAH A-allele carriers (55% noncarriers). Relative to controls, trauma-exposed youth demonstrated higher anxiety and higher FA of the left uncinate. The FAAH A-allele (vs. CC) was associated with lower FA in the left fornix and left parahippocampal cingulum, and there was an indirect effect of FAAH genotype on anxiety through FA of the left fornix. Moreover, genotype moderated the association between FA of the left cingulum and anxiety. Conclusions: Our findings demonstrate distinct effects of trauma exposure and the FAAH C385A variant on frontolimbic pathways and subsequent anxiety risk in preadolescent children. This line of work may provide important insights into neurodevelopmental mechanisms leading to anxiety risk, and potential targets for intervention.
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Affiliation(s)
- Hilary A. Marusak
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, USA
- Translational Neuroscience Graduate Program, Wayne State University School of Medicine, Detroit, Michigan, USA
- Merrill Palmer Skillman Institute for Child and Family Development, Wayne State University, Detroit, Michigan, USA
| | - Julia Evanski
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Shreya Desai
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Christine A. Rabinak
- Translational Neuroscience Graduate Program, Wayne State University School of Medicine, Detroit, Michigan, USA
- Merrill Palmer Skillman Institute for Child and Family Development, Wayne State University, Detroit, Michigan, USA
- Department of Pharmacy Practice and Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan, USA
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan, USA
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Singh P, Singh D, Srivastava P, Mishra G, Tiwari AK. Evaluation of advanced, pathophysiologic new targets for imaging of CNS. Drug Dev Res 2023; 84:484-513. [PMID: 36779375 DOI: 10.1002/ddr.22040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 12/12/2022] [Accepted: 12/31/2022] [Indexed: 02/14/2023]
Abstract
The inadequate information about the in vivo pathological, physiological, and neurological impairments, as well as the absence of in vivo tools for assessing brain penetrance and the efficiency of newly designed drugs, has hampered the development of new techniques for the treatment for variety of new central nervous system (CNS) diseases. The searching sites such as Science Direct and PubMed were used to find out the numerous distinct tracers across 16 CNS targets including tau, synaptic vesicle glycoprotein, the adenosine 2A receptor, the phosphodiesterase enzyme PDE10A, and the purinoceptor, among others. Among the most encouraging are [18 F]FIMX for mGluR imaging, [11 C]Martinostat for Histone deacetylase, [18 F]MNI-444 for adenosine 2A imaging, [11 C]ER176 for translocator protein, and [18 F]MK-6240 for tau imaging. We also reviewed the findings for each tracer's features and potential for application in CNS pathophysiology and therapeutic evaluation investigations, including target specificity, binding efficacy, and pharmacokinetic factors. This review aims to present a current evaluation of modern positron emission tomography tracers for CNS targets, with a focus on recent advances for targets that have newly emerged for imaging in humans.
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Affiliation(s)
- Priya Singh
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
| | - Deepika Singh
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
| | - Pooja Srivastava
- Division of Cyclotron and Radiopharmaceuticals Sciences, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - Gauri Mishra
- Department of Zoology, Swami Shraddhananad College, University of Delhi, Alipur, Delhi, India
| | - Anjani K Tiwari
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
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3
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Ferreira PC, Bellaver B, Povala G, Brum WS, Tissot C, Badji A, Sloan ME, Benedet AL, Rosa-Neto P, Ashton NJ, Pascoal TA, Leuzy A, Zimmer ER. Endocannabinoid System Biomarkers in Alzheimer's Disease. Cannabis Cannabinoid Res 2023; 8:77-91. [PMID: 36394442 PMCID: PMC10081722 DOI: 10.1089/can.2022.0151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Background: Alterations in the endocannabinoid system (ES) have been described in Alzheimer's disease (AD) pathophysiology. In the past years, multiple ES biomarkers have been developed, promising to advance our understanding of ES changes in AD. Discussion: ES biomarkers, including positron emission tomography with cannabinoid receptors tracers and biofluid-based endocannabinoids, are associated with AD disease progression and pathological features. Conclusion: Although not specific enough for AD diagnosis, ES biomarkers hold promise for prognosis, drug-target engagement, and a better understanding of the disease. Here, we summarize currently available ES biomarker findings and discuss their potential applications in the AD research field.
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Affiliation(s)
- Pâmela C.L. Ferreira
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Neurology and Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Bruna Bellaver
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Neurology and Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Guilherme Povala
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Neurology and Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Wagner S. Brum
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
| | - Cécile Tissot
- Department of Neurology and Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Translational Neuroimaging Laboratory, McGill University Research Centre for Studies in Aging, Alzheimer's Disease Research Unit, Douglas Research Institute, Le Centre intégré universitaire de santé et de services sociaux (CIUSSS) de l'Ouest-de-l'Île-de-Montréal, Montreal, QC, Canada
- Department of Neurology and Neurosurgery, Psychiatry and Pharmacology and Therapeutics, McGill University, Montreal, Canada
| | - Atef Badji
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
- Karolinska University Hospital, Theme Aging, Huddinge, Sweden
| | - Matthew E. Sloan
- Addictions Division, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Division of Neurosciences and Clinical Translation, Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada
- Department of Psychological Clinical Science, University of Toronto Scarborough, Toronto, Ontario, Canada
| | - Andréa L. Benedet
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory, McGill University Research Centre for Studies in Aging, Alzheimer's Disease Research Unit, Douglas Research Institute, Le Centre intégré universitaire de santé et de services sociaux (CIUSSS) de l'Ouest-de-l'Île-de-Montréal, Montreal, QC, Canada
- Department of Neurology and Neurosurgery, Psychiatry and Pharmacology and Therapeutics, McGill University, Montreal, Canada
| | - Nicholas J. Ashton
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience & Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden
- King's College London, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Institute Clinical Neuroscience Institute, London, United Kingdom
- NIHR Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation, London, United Kingdom
| | - Tharick A. Pascoal
- Department of Neurology and Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Antoine Leuzy
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Eduardo R. Zimmer
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Translational Neuroimaging Laboratory, McGill University Research Centre for Studies in Aging, Alzheimer's Disease Research Unit, Douglas Research Institute, Le Centre intégré universitaire de santé et de services sociaux (CIUSSS) de l'Ouest-de-l'Île-de-Montréal, Montreal, QC, Canada
- Department of Pharmacology, UFRGS, Porto Alegre, Brazil
- Graduate Program in Biological Sciences: Pharmacology and Therapeutics, UFRGS, Porto Alegre, Brazil
- Brain Institute of Rio Grande do Sul, PUCRS, Porto Alegre, Brazil
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Santoso AD, De Ridder D. Fatty Acid Amide Hydrolase: An Integrative Clinical Perspective. Cannabis Cannabinoid Res 2023; 8:56-76. [PMID: 35900294 DOI: 10.1089/can.2021.0237] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Introduction: Fatty acid amide hydrolase (FAAH) is one of the main terminating enzymes of the endocannabinoid system (ECS). Since being discovered in 1996, the modulation of FAAH has been viewed as a compelling alternative strategy to obtain the beneficial effect of the ECS. With a considerable amount of FAAH-related publication over time, the next step would be to comprehend the proximity of this evidence for clinical application. Objective: This review intends to highlight the rationale of FAAH modulation and provide the latest evidence from clinical studies. Methods: Publication searches were conducted to gather information focused on FAAH-related clinical evidence with an extension to the experimental research to understand the biological plausibility. The subtopics were selected to be multidisciplinary to offer more perspective on the current state of the arts. Discussion: Experimental and clinical studies have demonstrated that FAAH was highly expressed not only in the central nervous system but also in the peripheral tissues. As the key regulator of endocannabinoid signaling, it would appear that FAAH plays a role in the modulation of mood and emotional response, reward system, pain perception, energy metabolism and appetite regulation, inflammation, and other biological processes. Genetic variants may be associated with some conditions such as substance/alcohol use disorders, obesity, and eating disorder. The advancement of functional neuroimaging has enabled the evaluation of the neurochemistry of FAAH in brain tissues and this can be incorporated into clinical trials. Intriguingly, the application of FAAH inhibitors in clinical trials seems to provide less striking results in comparison with the animal models, although some potential still can be seen. Conclusion: Modulation of FAAH has an immense potential to be a new therapeutic candidate for several disorders. Further exploration, however, is still needed to ensure who is the best candidate for the treatment strategy.
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Affiliation(s)
- Anugrah D Santoso
- Laboratory of Experimental Urology, Department of Development and Regeneration, KU Leuven, Leuven, Belgium
- Department of Urology, Faculty of Medicine Universitas Airlangga, Dr. Soetomo General Academic Hospital, Surabaya, Indonesia
| | - Dirk De Ridder
- Laboratory of Experimental Urology, Department of Development and Regeneration, KU Leuven, Leuven, Belgium
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Watts JJ, Guma E, Chavez S, Tyndale RF, Ross RA, Houle S, Wilson AA, Chakravarty M, Rusjan PM, Mizrahi R. In vivo brain endocannabinoid metabolism is related to hippocampus glutamate and structure - a multimodal imaging study with PET, 1H-MRS, and MRI. Neuropsychopharmacology 2022; 47:1984-1991. [PMID: 35906490 PMCID: PMC9485131 DOI: 10.1038/s41386-022-01384-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 06/17/2022] [Accepted: 07/07/2022] [Indexed: 01/18/2023]
Abstract
Dysregulation of hippocampus glutamatergic neurotransmission and reductions in hippocampal volume have been associated with psychiatric disorders. The endocannabinoid system modulates glutamate neurotransmission and brain development, including hippocampal remodeling. In humans, elevated levels of anandamide and lower activity of its catabolic enzyme fatty acid amide hydrolase (FAAH) are associated with schizophrenia diagnosis and psychotic symptom severity, respectively (Neuropsychopharmacol, 29(11), 2108-2114; Biol. Psychiatry 88 (9), 727-735). Although preclinical studies provide strong evidence linking anandamide and FAAH to hippocampus neurotransmission and structure, these relationships remain poorly understood in humans. We recruited young adults with and without psychotic disorders and measured FAAH activity, hippocampal glutamate and glutamine (Glx), and hippocampal volume using [11C]CURB positron emission tomography (PET), proton magnetic resonance spectroscopy (1H-MRS) and T1-weighted structural MRI, respectively. We hypothesized that higher FAAH activity would be associated with greater hippocampus Glx and lower hippocampus volume, and that these effects would differ in patients with psychotic disorders relative to healthy control participants. After attrition and quality control, a total of 37 participants (62% male) completed [11C]CURB PET and 1H-MRS of the left hippocampus, and 45 (69% male) completed [11C]CURB PET and hippocampal volumetry. Higher FAAH activity was associated with greater concentration of hippocampal Glx (F1,36.36 = 9.17, p = 0.0045; Cohen's f = 0.30, medium effect size) and smaller hippocampal volume (F1,44.70 = 5.94, p = 0.019, Cohen's f = 0.26, medium effect size). These effects did not differ between psychosis and healthy control groups (no group interaction). This multimodal imaging study provides the first in vivo evidence linking hippocampal Glx and hippocampus volume with endocannabinoid metabolism in the human brain.
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Affiliation(s)
- Jeremy J Watts
- Research Centre, CHU Sainte-Justine, Montreal, QC, Canada
- Department of Psychiatry, Université de Montréal, Montreal, QC, Canada
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, ON, Canada
| | - Elisa Guma
- Computational Brain Anatomy (CoBrA) Laboratory, Cerebral Imaging Centre, Douglas Mental Health University Institute, Montreal, QC, Canada
- Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD, USA
| | - Sofia Chavez
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Rachel F Tyndale
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, ON, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Ruth A Ross
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, ON, Canada
| | - Sylvain Houle
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Alan A Wilson
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Mallar Chakravarty
- Computational Brain Anatomy (CoBrA) Laboratory, Cerebral Imaging Centre, Douglas Mental Health University Institute, Montreal, QC, Canada
- Department of Psychiatry, McGill University, Montreal, QC, Canada
- Douglas Mental Health University Institute, Montreal, QC, Canada
| | - Pablo M Rusjan
- Department of Psychiatry, McGill University, Montreal, QC, Canada
- Douglas Mental Health University Institute, Montreal, QC, Canada
| | - Romina Mizrahi
- Department of Psychiatry, McGill University, Montreal, QC, Canada.
- Douglas Mental Health University Institute, Montreal, QC, Canada.
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Green DGJ, Westwood DJ, Kim J, Best LM, Kish SJ, Tyndale RF, McCluskey T, Lobaugh NJ, Boileau I. Fatty acid amide hydrolase levels in brain linked with threat-related amygdala activation. NEUROIMAGE. REPORTS 2022; 2:100094. [PMID: 37235067 PMCID: PMC10206405 DOI: 10.1016/j.ynirp.2022.100094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 04/08/2022] [Accepted: 04/13/2022] [Indexed: 05/28/2023]
Abstract
Background Preclinical evidence suggests that increasing levels of the major endocannabinoid anandamide decreases anxiety and fear responses potentially through its effects in the amygdala. Here we used neuroimaging to test the hypothesis that lower fatty acid amide hydrolase (FAAH), the main catabolic enzyme for anandamide, is associated with a blunted amygdala response to threat. Methods Twenty-eight healthy participants completed a positron emission tomography (PET) scan with the radiotracer for FAAH, [11C]CURB, as well as a block-design functional magnetic resonance imaging session during which angry and fearful faces meant to activate the amygdala were presented. Results [11C]CURB binding in the amygdala as well as in the medial prefrontal cortex, cingulate and hippocampus correlated positively with blood-oxygen-level-dependent (BOLD) signal during processing of angry and fearful faces (pFWE < 0.05). Conclusion Our finding that lower levels of FAAH in amygdala, medial prefrontal cortex, cingulate and hippocampus was associated with a dampened amygdala response to a threatening social cue aligns with preclinical and neuroimaging studies in humans and suggests the involvement of FAAH in modulating stress and anxiety in humans. The current neuroimaging study also lends support for the potential use of FAAH inhibitors to control amygdala hyperactivity, which is known to be involved in the pathophysiology of anxiety and trauma-related disorders.
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Affiliation(s)
- Duncan GJ. Green
- Addiction Imaging Research Group, Canada
- Faculty of Medicine, University of Toronto, Toronto, Canada
| | | | - Jinhee Kim
- Departments of Psychiatry, Canada
- Department of Psychology, Korea University, Republic of Korea
| | - Laura M. Best
- Addiction Imaging Research Group, Canada
- Faculty of Medicine, University of Toronto, Toronto, Canada
| | - Stephen J. Kish
- Human Brain Lab, Canada
- Campbell Family Mental Health Research Institute, Canada
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada
- Departments of Psychiatry, Canada
- Pharmacology & Toxicology, Canada
- Faculty of Medicine, University of Toronto, Toronto, Canada
| | - Rachel F. Tyndale
- Campbell Family Mental Health Research Institute, Canada
- Departments of Psychiatry, Canada
- Pharmacology & Toxicology, Canada
| | - Tina McCluskey
- Human Brain Lab, Canada
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada
| | - Nancy J. Lobaugh
- Campbell Family Mental Health Research Institute, Canada
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada
- Faculty of Medicine, University of Toronto, Toronto, Canada
| | - Isabelle Boileau
- Addiction Imaging Research Group, Canada
- Campbell Family Mental Health Research Institute, Canada
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada
- Departments of Psychiatry, Canada
- Faculty of Medicine, University of Toronto, Toronto, Canada
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Ho W, Kolla NJ. The endocannabinoid system in borderline personality disorder and antisocial personality disorder: A scoping review. BEHAVIORAL SCIENCES & THE LAW 2022; 40:331-350. [PMID: 35575169 DOI: 10.1002/bsl.2576] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 02/06/2022] [Accepted: 03/31/2022] [Indexed: 06/15/2023]
Abstract
Individuals with borderline personality disorder (BPD) or antisocial personality disorder (ASPD) are overrepresented in forensic settings. Yet, despite the burden these disorders place on healthcare and criminal justice systems, there remains a lack of evidence-based pharmacological treatments. Epidemiological data have shown that comorbid cannabis use disorders are common in BPD and ASPD. ∆9 -Tetrahydrocannabinol, the primary psychoactive constituent of cannabis, is an exogenous cannabinoid that stimulates the endocannabinoid system (ECS). Hence, an investigation of the ECS in these conditions is warranted. This scoping review screened 105 records and summarized the extant research on the ECS in ASPD (n = 69) and BPD (n = 61) participants. Preliminary results suggest that alterations of the ECS may be present in these disorders. Although research examining the ECS in personality disorders is still in its infancy, more research is warranted given initial positive findings.
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Affiliation(s)
- Wilson Ho
- Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Nathan J Kolla
- Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Waypoint Centre for Mental Health Care, Penetanguishene, ON, Canada
- Waypoint/University of Toronto Research Chair in Forensic Mental Health Science, Penetanguishene, ON, Canada
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On the Biomedical Properties of Endocannabinoid Degradation and Reuptake Inhibitors: Pre-clinical and Clinical Evidence. Neurotox Res 2021; 39:2072-2097. [PMID: 34741755 DOI: 10.1007/s12640-021-00424-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/14/2021] [Accepted: 09/28/2021] [Indexed: 10/19/2022]
Abstract
The endocannabinoid system (ECS) is composed of endogenous cannabinoids; components involved in their synthesis, transport, and degradation; and an expansive variety of cannabinoid receptors. Hypofunction or deregulation of the ECS is related to pathological conditions. Consequently, endogenous enhancement of endocannabinoid levels and/or regulation of their metabolism represent promising therapeutic approaches. Several major strategies have been suggested for the modulation of the ECS: (1) blocking endocannabinoids degradation, (2) inhibition of endocannabinoid cellular uptake, and (3) pharmacological modulation of cannabinoid receptors as potential therapeutic targets. Here, we focused in this review on degradation/reuptake inhibitors over cannabinoid receptor modulators in order to provide an updated synopsis of contemporary evidence advancing mechanisms of endocannabinoids as pharmacological tools with therapeutic properties for the treatment of several disorders. For this purpose, we revisited the available literature and reported the latest advances regarding the biomedical properties of fatty acid amide hydrolase and monoacylglycerol lipase inhibitors in pre-clinical and clinical studies. We also highlighted anandamide and 2-arachidonoylglycerol reuptake inhibitors with promising results in pre-clinical studies using in vitro and animal models as an outlook for future research in clinical trials.
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9
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Green DGJ, Kim J, Kish SJ, Tyndale RF, Hill MN, Strafella AP, Tong J, McCluskey T, Westwood DJ, Houle S, Lobaugh NJ, Boileau I. Fatty acid amide hydrolase binding is inversely correlated with amygdalar functional connectivity: a combined positron emission tomography and magnetic resonance imaging study in healthy individuals. J Psychiatry Neurosci 2021; 46:E238-E246. [PMID: 33729738 PMCID: PMC8061733 DOI: 10.1503/jpn.200010] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Upregulation of the endocannabinoid enzyme fatty acid amide hydrolase (FAAH) has been linked to abnormal activity in frontoamygdalar circuits, a hallmark of posttraumatic stress disorder. We tested the hypothesis that FAAH levels in the amygdala were negatively correlated with functional connectivity between the amygdala and prefrontal cortex, subserving stress and affect control. METHODS Thirty-one healthy participants completed positron emission tomography (PET) imaging with the FAAH probe [C-11]CURB, and resting-state functional MRI scans. Participants were genotyped for the FAAH polymorphism rs324420, and trait neuroticism was assessed. We calculated amygdala functional connectivity using predetermined regions of interest (including the subgenual ventromedial prefrontal cortex [sgvmPFC] and the dorsal anterior cingulate cortex [dACC]) and a seed-to-voxel approach. We conducted correlation analyses on functional connectivity, with amygdala [C-11]CURB binding as a variable of interest. RESULTS The strength of amygdala functional connectivity with the sgvmPFC and dACC was negatively correlated with [C-11]CURB binding in the amygdala (sgvmPFC: r = -0.38, q = 0.04; dACC: r = -0.44; q = 0.03). Findings were partly replicated using the seed-to-voxel approach, which showed a cluster in the ventromedial prefrontal cortex, including voxels in the dACC but not the sgvmPFC (cluster-level, family-wise error rate corrected p < 0.05). LIMITATIONS We did not replicate earlier findings of a relationship between an FAAH polymorphism (rs324420) and amygdala functional connectivity. CONCLUSION Our data provide preliminary evidence that lower levels of FAAH in the amygdala relate to increased frontoamygdalar functional coupling. Our findings were consistent with the role of FAAH in regulating brain circuits that underlie fear and emotion processing in humans.
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Affiliation(s)
- Duncan G J Green
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Jinhee Kim
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Stephen J Kish
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Rachel F Tyndale
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Matthew N Hill
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Antonio P Strafella
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Junchao Tong
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Tina McCluskey
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Duncan J Westwood
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Sylvain Houle
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Nancy J Lobaugh
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
| | - Isabelle Boileau
- From the Addiction Imaging Research Group, Toronto, Ont., Canada (Green, Westwood, Boileau); the Human Brain Lab, Toronto, Ont., Canada (Kish, Tong, McCluskey); the Campbell Family Mental Health Research Institute, Ont., Canada (Kim, Tyndale, Strafella, Houle, Lobaugh, Boileau); the Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Kim, Kish, Strafella, Tong, McCluskey, Houle, Lobaugh); the Departments of Psychiatry, Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale, Strafella, Houle, Boileau); the Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ont., Canada (Kish, Tyndale); the Institute of Medical Sciences, University of Toronto, Toronto, Ont., Canada (Green, Kish, Houle, Lobaugh, Boileau); the Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary, Alta., Canada (Hill); the Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Toronto, Ont., Canada (Strafella); and the Division of Neurology, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada (Lobaugh)
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Pinna G. Endocannabinoids and Precision Medicine for Mood Disorders and Suicide. Front Psychiatry 2021; 12:658433. [PMID: 34093274 PMCID: PMC8173054 DOI: 10.3389/fpsyt.2021.658433] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 04/09/2021] [Indexed: 12/04/2022] Open
Affiliation(s)
- Graziano Pinna
- The Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, United States
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11
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Jacobson MR, Watts JJ, Da Silva T, Tyndale RF, Rusjan PM, Houle S, Wilson AA, Ross RA, Boileau I, Mizrahi R. Fatty acid amide hydrolase is lower in young cannabis users. Addict Biol 2021; 26:e12872. [PMID: 31960544 DOI: 10.1111/adb.12872] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 11/03/2019] [Accepted: 12/21/2019] [Indexed: 12/31/2022]
Abstract
We have recently shown that levels of fatty acid amide hydrolase (FAAH), the enzyme that metabolizes the endocannabinoid anandamide, are lower in the brains of adult cannabis users (CUs) (34 ± 11 years of age), tested during early abstinence. Here, we examine replication of the lower FAAH levels in a separate, younger cohort (23 ± 5 years of age). Eighteen healthy volunteers (HVs) and fourteen CUs underwent a positron emission tomography scan using the FAAH radioligand [11 C]CURB. Regional [11 C]CURB binding was calculated using an irreversible two-tissue compartment model with a metabolite-corrected arterial plasma input function. The FAAH C385A genetic polymorphism (rs324420) was included as a covariate. All CUs underwent a urine screen to confirm recent cannabis use and had serum cannabinoids measured. One CU screened negative for cannabinoids via serum and was removed from analysis. All HVs reported less than five lifetime cannabis exposures more than a month prior to study initiation. There was a significant effect of group (F1,26 = 4.31; P = .048) when two A/A (rs324420) HVs were removed from analysis to match the genotype of the CU group (n = 16 HVs, n = 13 CUs). Overall, [11 C]CURB λk3 was 12% lower in CU compared with HV. Exploratory correlations showed that lower brain [11 C]CURB binding was related to greater use of cannabis throughout the past year. We confirmed our previous report and extended these findings by detecting lower [11 C]CURB binding in a younger cohort with less cumulative cannabis exposure.
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Affiliation(s)
- Maya R. Jacobson
- Research Imaging Centre Centre for Addiction and Mental Health Toronto Ontario Canada
- Department of Pharmacology and Toxicology University of Toronto Toronto Ontario Canada
- Campbell Family Mental Health Research Institute Centre for Addiction and Mental Health Toronto Ontario Canada
| | - Jeremy J. Watts
- Research Imaging Centre Centre for Addiction and Mental Health Toronto Ontario Canada
- Department of Pharmacology and Toxicology University of Toronto Toronto Ontario Canada
- Campbell Family Mental Health Research Institute Centre for Addiction and Mental Health Toronto Ontario Canada
| | - Tania Da Silva
- Research Imaging Centre Centre for Addiction and Mental Health Toronto Ontario Canada
- Campbell Family Mental Health Research Institute Centre for Addiction and Mental Health Toronto Ontario Canada
| | - Rachel F. Tyndale
- Department of Pharmacology and Toxicology University of Toronto Toronto Ontario Canada
- Department of Psychiatry University of Toronto Toronto Ontario Canada
- Campbell Family Mental Health Research Institute Centre for Addiction and Mental Health Toronto Ontario Canada
| | - Pablo M. Rusjan
- Research Imaging Centre Centre for Addiction and Mental Health Toronto Ontario Canada
- Department of Psychiatry University of Toronto Toronto Ontario Canada
- Campbell Family Mental Health Research Institute Centre for Addiction and Mental Health Toronto Ontario Canada
| | - Sylvain Houle
- Research Imaging Centre Centre for Addiction and Mental Health Toronto Ontario Canada
- Department of Psychiatry University of Toronto Toronto Ontario Canada
- Campbell Family Mental Health Research Institute Centre for Addiction and Mental Health Toronto Ontario Canada
| | - Alan A. Wilson
- Research Imaging Centre Centre for Addiction and Mental Health Toronto Ontario Canada
- Department of Psychiatry University of Toronto Toronto Ontario Canada
| | - Ruth A. Ross
- Department of Pharmacology and Toxicology University of Toronto Toronto Ontario Canada
| | - Isabelle Boileau
- Research Imaging Centre Centre for Addiction and Mental Health Toronto Ontario Canada
- Department of Psychiatry University of Toronto Toronto Ontario Canada
- Campbell Family Mental Health Research Institute Centre for Addiction and Mental Health Toronto Ontario Canada
| | - Romina Mizrahi
- Research Imaging Centre Centre for Addiction and Mental Health Toronto Ontario Canada
- Department of Pharmacology and Toxicology University of Toronto Toronto Ontario Canada
- Department of Psychiatry University of Toronto Toronto Ontario Canada
- Campbell Family Mental Health Research Institute Centre for Addiction and Mental Health Toronto Ontario Canada
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12
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Watts JJ, Jacobson MR, Lalang N, Boileau I, Tyndale RF, Kiang M, Ross RA, Houle S, Wilson AA, Rusjan P, Mizrahi R. Imaging Brain Fatty Acid Amide Hydrolase in Untreated Patients With Psychosis. Biol Psychiatry 2020; 88:727-735. [PMID: 32387132 PMCID: PMC8240477 DOI: 10.1016/j.biopsych.2020.03.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 03/01/2020] [Accepted: 03/04/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND The brain's endocannabinoid system, the primary target of cannabis, has been implicated in psychosis. The endocannabinoid anandamide is elevated in cerebrospinal fluid of patients with schizophrenia. Fatty acid amide hydrolase (FAAH) controls brain anandamide levels; however, it is unknown if FAAH is altered in vivo in psychosis or related to positive psychotic symptoms. METHODS Twenty-seven patients with schizophrenia spectrum disorders and 36 healthy control subjects completed high-resolution positron emission tomography scans with the novel FAAH radioligand [11C]CURB and structural magnetic resonance imaging. Data were analyzed using the validated irreversible 2-tissue compartment model with a metabolite-corrected arterial input function. RESULTS FAAH did not differ significantly between patients with psychotic disorders and healthy control subjects (F1,62.85 = 0.48, p = .49). In contrast, lower FAAH predicted greater positive psychotic symptom severity, with the strongest effect observed for the positive symptom dimension, which includes suspiciousness, delusions, unusual thought content, and hallucinations (F1,26.69 = 12.42, p = .002; Cohen's f = 0.42, large effect). Shorter duration of illness (F1,26.95 = 13.78, p = .001; Cohen's f = 0.39, medium to large effect) and duration of untreated psychosis predicted lower FAAH (F1,26.95 = 6.03, p = .021, Cohen's f = 0.27, medium effect). These results were not explained by past cannabis exposure or current intake of antipsychotic medications. FAAH exhibited marked differences across brain regions (F7,112.62 = 175.85, p < 1 × 10-56; Cohen's f > 1). Overall, FAAH was higher in female subjects than in male subjects (F1,62.84 = 10.05, p = .002; Cohen's f = 0.37). CONCLUSIONS This first study of brain FAAH in psychosis indicates that FAAH may represent a biomarker of disease state of potential utility for clinical studies targeting psychotic symptoms or as a novel target for interventions to treat psychotic symptoms.
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Affiliation(s)
- Jeremy J Watts
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada,Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Maya R Jacobson
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada,Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Nittha Lalang
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada,Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Isabelle Boileau
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada,Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Rachel F Tyndale
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Michael Kiang
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Ruth A Ross
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Sylvain Houle
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Alan A Wilson
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Pablo Rusjan
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada,Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Romina Mizrahi
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.
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13
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Lower brain fatty acid amide hydrolase in treatment-seeking patients with alcohol use disorder: a positron emission tomography study with [C-11]CURB. Neuropsychopharmacology 2020; 45:1289-1296. [PMID: 31910433 PMCID: PMC7298050 DOI: 10.1038/s41386-020-0606-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 12/31/2019] [Accepted: 12/31/2019] [Indexed: 01/23/2023]
Abstract
The endocannabinoid enzyme, fatty acid amide hydrolase (FAAH), has been proposed as a therapeutic target for alcohol use disorder (AUD) and co-morbid psychiatric illnesses. Investigating this target in the living human brain and its relationship to clinical outcome is a critical step of informed drug development. Our objective was to establish whether brain FAAH levels are low in individuals with AUD and related to drinking behavior. In this pilot study, treatment-seeking patients with AUD completed two PET scans with the FAAH radiotracer [C-11]CURB after 3-7 days (n = 14) and 2-4 weeks (n = 9) of monitored abstinence. Healthy controls (n = 25) completed one scan. FAAH genetic polymorphism (rs324420) and blood concentrations of anandamide and other N-acylethanolamines metabolized by FAAH were determined and AUD symptoms assessed. In AUD, brain FAAH levels were globally lower than controls during early abstinence (F(1,36) = 5.447; p = 0.025)) and FAAH substrates (anandamide, oleoylethanolamide, and N-docosahexaenoylethanolamide) were significantly elevated (30-67%). No significant differences in FAAH or FAAH substrates were noted after 2-4 weeks abstinence. FAAH levels negatively correlated with drinks per week (r = -0.57, p = 0.032) and plasma concentrations of the three FAAH substrates (r > 0.57; p < 0.04)). Our findings suggest that early abstinence from alcohol in AUD is associated with transiently low brain FAAH levels, which are inversely related to heavier alcohol use and elevated plasma levels of FAAH substrates. Whether low FAAH is an adaptive beneficial response to chronic alcohol is unknown. Therapeutic strategies focusing on FAAH inhibition should consider the possibility that low FAAH during early abstinence may be related to drinking.
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14
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McCluskey SP, Plisson C, Rabiner EA, Howes O. Advances in CNS PET: the state-of-the-art for new imaging targets for pathophysiology and drug development. Eur J Nucl Med Mol Imaging 2020; 47:451-489. [PMID: 31541283 PMCID: PMC6974496 DOI: 10.1007/s00259-019-04488-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 08/15/2019] [Indexed: 02/07/2023]
Abstract
PURPOSE A limit on developing new treatments for a number of central nervous system (CNS) disorders has been the inadequate understanding of the in vivo pathophysiology underlying neurological and psychiatric disorders and the lack of in vivo tools to determine brain penetrance, target engagement, and relevant molecular activity of novel drugs. Molecular neuroimaging provides the tools to address this. This article aims to provide a state-of-the-art review of new PET tracers for CNS targets, focusing on developments in the last 5 years for targets recently available for in-human imaging. METHODS We provide an overview of the criteria used to evaluate PET tracers. We then used the National Institute of Mental Health Research Priorities list to identify the key CNS targets. We conducted a PubMed search (search period 1st of January 2013 to 31st of December 2018), which yielded 40 new PET tracers across 16 CNS targets which met our selectivity criteria. For each tracer, we summarised the evidence of its properties and potential for use in studies of CNS pathophysiology and drug evaluation, including its target selectivity and affinity, inter and intra-subject variability, and pharmacokinetic parameters. We also consider its potential limitations and missing characterisation data, but not specific applications in drug development. Where multiple tracers were present for a target, we provide a comparison of their properties. RESULTS AND CONCLUSIONS Our review shows that multiple new tracers have been developed for proteinopathy targets, particularly tau, as well as the purinoceptor P2X7, phosphodiesterase enzyme PDE10A, and synaptic vesicle glycoprotein 2A (SV2A), amongst others. Some of the most promising of these include 18F-MK-6240 for tau imaging, 11C-UCB-J for imaging SV2A, 11C-CURB and 11C-MK-3168 for characterisation of fatty acid amide hydrolase, 18F-FIMX for metabotropic glutamate receptor 1, and 18F-MNI-444 for imaging adenosine 2A. Our review also identifies recurrent issues within the field. Many of the tracers discussed lack in vivo blocking data, reducing confidence in selectivity. Additionally, late-stage identification of substantial off-target sites for multiple tracers highlights incomplete pre-clinical characterisation prior to translation, as well as human disease state studies carried out without confirmation of test-retest reproducibility.
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Affiliation(s)
- Stuart P McCluskey
- Invicro LLC, A Konica Minolta Company, Burlington Danes Building, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK.
- Psychiatric Imaging Group, MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London, UK.
| | - Christophe Plisson
- Invicro LLC, A Konica Minolta Company, Burlington Danes Building, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK
| | - Eugenii A Rabiner
- Invicro LLC, A Konica Minolta Company, Burlington Danes Building, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK
| | - Oliver Howes
- Psychiatric Imaging Group, MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London, UK
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15
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Locci A, Pinna G. Social isolation as a promising animal model of PTSD comorbid suicide: neurosteroids and cannabinoids as possible treatment options. Prog Neuropsychopharmacol Biol Psychiatry 2019; 92:243-259. [PMID: 30586627 DOI: 10.1016/j.pnpbp.2018.12.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 12/18/2018] [Accepted: 12/21/2018] [Indexed: 02/07/2023]
Abstract
Post-traumatic stress disorder (PTSD) is a psychiatric condition characterized by drastic alterations in mood, emotions, social abilities and cognition. Notably, one aspect of PTSD, particularly in veterans, is its comorbidity with suicide. Elevated aggressiveness predicts high-risk to suicide in humans and despite the difficulty in reproducing a complex human suicidal behavior in rodents, aggressive behavior is a well reproducible behavioral trait of suicide. PTSD animal models are based on a peculiar phenotype, including exaggerated fear memory and impaired fear extinction associated with neurochemical dysregulations in the brain circuitry regulating emotion. The endocannabinoid and the neurosteroid systems regulate emotions and stress responses, and recent evidence shows these two systems are interrelated and critically compromised in neuropsychiatric disorders. For instance, levels of the neurosteroid, allopregnanolone, as well as those of the endocannabinoids, anandamide and its congener, palmitoylethanolamide are decreased in PTSD. Similarly, the endocannabinoid system and neurosteroid biosynthesis are altered in suicidal individuals. Selective serotonin reuptake inhibitors (SSRIs), the only FDA-approved treatments for PTSD, fail to help half of the treatment-seeking patients. This highlights the need for developing biomarker-based efficient therapies. One promising alternative to SSRIs points to stimulation of allopregnanolone biosynthesis as a treatment and a valid end-point to predict treatment response in PTSD patients. This review highlights running findings on the role of the endocannabinoid and neurosteroid systems in PTSD and suicidal behavior both in a preclinical and clinical perspective. A specific focus is given to predictive PTSD/suicide animal models. Ultimately, we discuss the idea that disruption of neurosteroid and endocannabinoid biosynthesis may offer a novel promising biomarker axis to develop new treatments for PTSD and, perhaps, suicidal behavior.
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Affiliation(s)
- Andrea Locci
- The Psychiatric Institute, Department of Psychiatry, College of Medicine, University of Illinois at Chicago, 1601 W. Taylor St., Chicago, IL 60612, USA
| | - Graziano Pinna
- The Psychiatric Institute, Department of Psychiatry, College of Medicine, University of Illinois at Chicago, 1601 W. Taylor St., Chicago, IL 60612, USA.
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16
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Sloan ME, Grant CW, Gowin JL, Ramchandani VA, Le Foll B. Endocannabinoid signaling in psychiatric disorders: a review of positron emission tomography studies. Acta Pharmacol Sin 2019; 40:342-350. [PMID: 30166624 PMCID: PMC6460371 DOI: 10.1038/s41401-018-0081-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 06/18/2018] [Indexed: 12/28/2022] Open
Abstract
Endocannabinoid signaling is implicated in an array of psychopathologies ranging from anxiety to psychosis and addiction. In recent years, radiotracers targeting the endocannabinoid system have been used in positron emission tomography (PET) studies to determine whether individuals with psychiatric disorders display altered endocannabinoid signaling. We comprehensively reviewed PET studies examining differences in endocannabinoid signaling between individuals with psychiatric illness and healthy controls. Published studies evaluated individuals with five psychiatric disorders: cannabis use disorder, alcohol use disorder, schizophrenia, post-traumatic stress disorder, and eating disorders. Most studies employed radiotracers targeting cannabinoid receptor 1 (CB1). Cannabis users consistently demonstrated decreased CB1 binding compared to controls, with normalization following short periods of abstinence. Findings in those with alcohol use disorder and schizophrenia were less consistent, with some studies demonstrating increased CB1 binding and others demonstrating decreased CB1 binding. Evidence of aberrant CB1 binding was also found in individuals with anorexia nervosa and post-traumatic stress disorder, but limited data have been published to date. Thus, existing evidence suggests that alterations in endocannabinoid signaling are present in a range of psychiatric disorders. Although recent efforts have largely focused on evaluating CB1 binding, the synthesis of new radiotracers targeting enzymes involved in endocannabinoid degradation, such as fatty acid amide hydrolase, will allow for other facets of endocannabinoid signaling to be evaluated in future studies.
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Affiliation(s)
- Matthew E Sloan
- Section on Human Psychopharmacology, Division of Intramural Clinical and Biological Research, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, 20814, USA
| | - Caroline W Grant
- Office of the Clinical Director, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, 20814, USA
| | - Joshua L Gowin
- Section on Human Psychopharmacology, Division of Intramural Clinical and Biological Research, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, 20814, USA
| | - Vijay A Ramchandani
- Section on Human Psychopharmacology, Division of Intramural Clinical and Biological Research, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, 20814, USA
| | - Bernard Le Foll
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, M5S 2S1, Canada.
- Addiction Medicine Service, Centre for Addiction and Mental Health, Toronto, ON, M6J 1H4, Canada.
- Departments of Family and Community Medicine, Pharmacology and Toxicology, Psychiatry, Institute of Medical Science, University of Toronto, Toronto, ON, M5S 2S1, Canada.
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, M6J 1H4, Canada.
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17
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Abstract
Hydrolytic enzymes are a large class of biological catalysts that play a vital role in a plethora of critical biochemical processes required to maintain human health. However, the expression and/or activity of these important enzymes can change in many different diseases and therefore represent exciting targets for the development of positron emission tomography (PET) and single-photon emission computed tomography (SPECT) radiotracers. This review focuses on recently reported radiolabeled substrates, reversible inhibitors, and irreversible inhibitors investigated as PET and SPECT tracers for imaging hydrolytic enzymes. By learning from the most successful examples of tracer development for hydrolytic enzymes, it appears that an early focus on careful enzyme kinetics and cell-based studies are key factors for identifying potentially useful new molecular imaging agents.
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Affiliation(s)
- Brian P Rempel
- 1 Department of Science, Augustana Faculty, University of Alberta, Edmonton, Alberta, Canada
| | - Eric W Price
- 2 Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Christopher P Phenix
- 2 Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,3 Biomarker Discovery, Thunder Bay Regional Health Research Institute, Thunder Bay, Ontario, Canada
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18
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Rusjan PM, Knezevic D, Boileau I, Tong J, Mizrahi R, Wilson AA, Houle S. Voxel level quantification of [11C]CURB, a radioligand for Fatty Acid Amide Hydrolase, using high resolution positron emission tomography. PLoS One 2018; 13:e0192410. [PMID: 29444138 PMCID: PMC5812639 DOI: 10.1371/journal.pone.0192410] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 01/23/2018] [Indexed: 11/18/2022] Open
Abstract
[11C]CURB is a novel irreversible radioligand for imaging fatty acid amide hydrolase in the human brain. In the present work, we validate an algorithm for generating parametric map images of [11C]CURB acquired with a high resolution research tomograph (HRRT) scanner. This algorithm applies the basis function method on an irreversible two-tissue compartment model (k4 = 0) with arterial input function, i.e., BAFPIC. Monte Carlo simulations are employed to assess bias and variability of the binding macroparameters (Ki and λk3) as a function of the voxel noise level and the range of basis functions. The results show that for a [11C]CURB time activity curve with noise levels corresponding to a voxel of an image acquired with the HRRT and reconstructed with the filtered back projection algorithm, the implementation of BAFPIC requires the use of a constant vascular fraction of tissue (5%) and a cutoff for slow frequencies (0.06 min-1). With these settings, BAFPIC maintains the probabilistic distributions of the binding macroparameters with approximately Gaussian shape and minimizes the bias and variability for large physiological ranges of the rate constants of [11C]CURB. BAFPIC reduces the variability of Ki to a third of that given by Patlak plot, the standard graphical method for irreversible radioligands. Application to real data demonstrated an excellent correlation between region of interest and BAFPIC parametric data and agreed with the simulations results. Therefore, BAFPIC with a constant vascular fraction can be used to generate parametric maps of [11C]CURB images acquired with an HRRT provided that the limits of the basis functions are carefully selected.
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Affiliation(s)
- Pablo M. Rusjan
- Research Imaging Centre, CAMH Campbell Family Mental Health Research Institute, Toronto, Ontario, Canada
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
| | - Dunja Knezevic
- Research Imaging Centre, CAMH Campbell Family Mental Health Research Institute, Toronto, Ontario, Canada
| | - Isabelle Boileau
- Research Imaging Centre, CAMH Campbell Family Mental Health Research Institute, Toronto, Ontario, Canada
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Junchao Tong
- Research Imaging Centre, CAMH Campbell Family Mental Health Research Institute, Toronto, Ontario, Canada
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Romina Mizrahi
- Research Imaging Centre, CAMH Campbell Family Mental Health Research Institute, Toronto, Ontario, Canada
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Alan A. Wilson
- Research Imaging Centre, CAMH Campbell Family Mental Health Research Institute, Toronto, Ontario, Canada
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Sylvain Houle
- Research Imaging Centre, CAMH Campbell Family Mental Health Research Institute, Toronto, Ontario, Canada
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
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19
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Schifani C, Hafizi S, Da Silva T, Watts JJ, Khan MS, Mizrahi R. Using molecular imaging to understand early schizophrenia-related psychosis neurochemistry: a review of human studies. Int Rev Psychiatry 2017; 29:555-566. [PMID: 29219634 PMCID: PMC8011813 DOI: 10.1080/09540261.2017.1396205] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Schizophrenia is a chronic psychiatric disorder generally preceded by a so-called prodromal phase, which is characterized by attenuated psychotic symptoms. Advances in clinical research have enabled prospective identification of those individuals who are at clinical high risk (CHR) for psychosis, with the power to predict psychosis onset within the near future. Changes in several brain neurochemical systems and molecular mechanisms are implicated in the pathophysiology of schizophrenia and the psychosis spectrum, including the dopaminergic, γ-aminobutyric acid (GABA)-ergic, glutamatergic, endocannabinoid, and immunologic (i.e. glial activation) system and other promising future directions such as synaptic density, which are possible to quantify in vivo using positron emission tomography (PET). This paper aims to review in vivo PET studies in the mentioned systems in the early course of psychosis (i.e. CHR and first-episode psychosis (FEP)). The results of reviewed studies are promising; however, the current understanding of the underlying pathology of psychosis is still limited. Importantly, promising efforts involve the development of novel PET radiotracers targeting systems with growing interest in schizophrenia, like the nociceptive system and synaptic density.
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Affiliation(s)
- Christin Schifani
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Sina Hafizi
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Tania Da Silva
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Jeremy Joseph Watts
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - M. Saad Khan
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Romina Mizrahi
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
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20
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Tong J, Mizrahi R, Houle S, Kish SJ, Boileau I, Nobrega J, Rusjan PM, Wilson AA. Inhibition of fatty acid amide hydrolase by BIA 10-2474 in rat brain. J Cereb Blood Flow Metab 2017; 37:3635-3639. [PMID: 27650910 PMCID: PMC5669339 DOI: 10.1177/0271678x16668890] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In a recent clinical trial, the drug BIA 10-2474, a putative fatty acid amide hydrolase(FAAH) inhibitor, was responsible for severe adverse events (SAEs), including one death. To date, there has been little reliable information divulged about the potency of BIA 10-2474 at FAAH in the central nervous system. We synthesised BIA 10-2474 and determined its ability to inhibit FAAH ex vivo in rat brain using a FAAH selective radiotracer. BIA 10-2474 proved to be a potent FAAH inhibitor with IC50s of 50-70 µg/kg (i.p.) in various brain regions. This information may be useful for determining the cause of the SAEs.
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Affiliation(s)
- Junchao Tong
- Research Imaging Centre, Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Toronto, ON, Canada
| | - Romina Mizrahi
- Research Imaging Centre, Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Toronto, ON, Canada
| | - Sylvain Houle
- Research Imaging Centre, Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Toronto, ON, Canada
| | - Stephen J Kish
- Research Imaging Centre, Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Toronto, ON, Canada
| | - Isabelle Boileau
- Research Imaging Centre, Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Toronto, ON, Canada
| | - Jose Nobrega
- Research Imaging Centre, Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Toronto, ON, Canada
| | - Pablo M Rusjan
- Research Imaging Centre, Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Toronto, ON, Canada
| | - Alan A Wilson
- Research Imaging Centre, Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Toronto, ON, Canada
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21
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Sloan ME, Gowin JL, Ramchandani VA, Hurd YL, Le Foll B. The endocannabinoid system as a target for addiction treatment: Trials and tribulations. Neuropharmacology 2017; 124:73-83. [PMID: 28564576 DOI: 10.1016/j.neuropharm.2017.05.031] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 05/24/2017] [Accepted: 05/26/2017] [Indexed: 12/19/2022]
Abstract
Addiction remains a major public health concern, and while pharmacotherapies can be effective, clinicians are limited by the paucity of existing interventions. Endocannabinoid signaling is involved in reward and addiction, which raises the possibility that drugs targeting this system could be used to treat substance use disorders. This review discusses findings from randomized controlled trials evaluating cannabinergic medications for addiction. Current evidence suggests that pharmacotherapies containing delta-9-tetrahydrocannabinol, such as dronabinol and nabiximols, are effective for cannabis withdrawal. Dronabinol may also reduce symptoms of opioid withdrawal. The cannabinoid receptor 1 (CB1) inverse agonist rimonabant showed promising effects for smoking cessation but also caused psychiatric side effects and currently lacks regulatory approval. Few trials have investigated cannabinergic medications for alcohol use disorder. Overall, the endocannabinoid system remains a promising target for addiction treatment. Development of novel medications such as fatty acid amide hydrolase inhibitors and neutral CB1 antagonists promises to extend the range of available interventions. This article is part of the Special Issue entitled "A New Dawn in Cannabinoid Neurobiology".
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Affiliation(s)
- Matthew E Sloan
- Section on Human Psychopharmacology, National Institute on Alcohol Abuse and Alcoholism, 10 Center Drive (10CRC, 2-2352), Bethesda, MD, 20892-1540, USA
| | - Joshua L Gowin
- Section on Human Psychopharmacology, National Institute on Alcohol Abuse and Alcoholism, 10 Center Drive (10CRC, 2-2352), Bethesda, MD, 20892-1540, USA
| | - Vijay A Ramchandani
- Section on Human Psychopharmacology, National Institute on Alcohol Abuse and Alcoholism, 10 Center Drive (10CRC, 2-2352), Bethesda, MD, 20892-1540, USA
| | - Yasmin L Hurd
- Departments of Psychiatry, Neuroscience, Pharmacology, and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, Hess CSM Building, Floor 10, Rm 105, Office 1470, Madison Avenue, New York, NY, 10029, USA
| | - Bernard Le Foll
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 33 Russell Street, Toronto, Ontario, M5S 2S1, Canada; Addiction Medicine Service, Ambulatory Care and Structured Treatments, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Departments of Family and Community Medicine, Pharmacology and Toxicology, and Psychiatry, Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.
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22
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Dahl K, Halldin C, Schou M. New methodologies for the preparation of carbon-11 labeled radiopharmaceuticals. Clin Transl Imaging 2017; 5:275-289. [PMID: 28596949 PMCID: PMC5437136 DOI: 10.1007/s40336-017-0223-1] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 02/01/2017] [Indexed: 12/04/2022]
Abstract
PURPOSE This short review aims to cover the more recent and promising developments of carbon-11 (11C) labeling radiochemistry and its utility in the production of novel radiopharmaceuticals, with special emphasis on methods that have the greatest potential to be translated for clinical positron emission tomography (PET) imaging. METHODS A survey of the literature was undertaken to identify articles focusing on methodological development in 11C chemistry and their use within novel radiopharmaceutical preparation. However, since 11C-labeling chemistry is such a narrow field of research, no systematic literature search was therefore feasible. The survey was further restricted to a specific timeframe (2000-2016) and articles in English. RESULTS From the literature, it is clear that the majority of 11C-labeled radiopharmaceuticals prepared for clinical PET studies have been radiolabeled using the standard heteroatom methylation reaction. However, a number of methodologies have been developed in recent years, both from a technical and chemical point of view. Amongst these, two protocols may have the greatest potential to be widely adapted for the preparation of 11C-radiopharmaceuticals in a clinical setting. First, a novel method for the direct formation of 11C-labeled carbonyl groups, where organic bases are utilized as [11C]carbon dioxide-fixation agents. The second method of clinical importance is a low-pressure 11C-carbonylation technique that utilizes solvable xenon gas to effectively transfer and react [11C]carbon monoxide in a sealed reaction vessel. Both methods appear to be general and provide simple paths to 11C-labeled products. CONCLUSION Radiochemistry is the foundation of PET imaging which relies on the administration of a radiopharmaceutical. The demand for new radiopharmaceuticals for clinical PET imaging is increasing, and 11C-radiopharmaceuticals are especially important within clinical research and drug development. This review gives a comprehensive overview of the most noteworthy 11C-labeling methods with clinical relevance to the field of PET radiochemistry.
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Affiliation(s)
- Kenneth Dahl
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Hospital, Karolinska Institutet, 171 76 Stockholm, Sweden
| | - Christer Halldin
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Hospital, Karolinska Institutet, 171 76 Stockholm, Sweden
| | - Magnus Schou
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Hospital, Karolinska Institutet, 171 76 Stockholm, Sweden
- Department of Clinical Neuroscience, AstraZeneca Translational Science Centre, Karolinska Institutet, 171 76 Stockholm, Sweden
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23
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Brain uptake and metabolism of the endocannabinoid anandamide labeled in either the arachidonoyl or ethanolamine moiety. Nucl Med Biol 2017; 45:43-50. [DOI: 10.1016/j.nucmedbio.2016.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 10/27/2016] [Accepted: 11/01/2016] [Indexed: 12/20/2022]
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24
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Boileau I, Mansouri E, Williams B, Le Foll B, Rusjan P, Mizrahi R, Tyndale RF, Huestis MA, Payer DE, Wilson AA, Houle S, Kish SJ, Tong J. Fatty Acid Amide Hydrolase Binding in Brain of Cannabis Users: Imaging With the Novel Radiotracer [ 11C]CURB. Biol Psychiatry 2016; 80:691-701. [PMID: 27345297 PMCID: PMC5050070 DOI: 10.1016/j.biopsych.2016.04.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 03/24/2016] [Accepted: 04/18/2016] [Indexed: 01/01/2023]
Abstract
BACKGROUND One of the major mechanisms for terminating the actions of the endocannabinoid anandamide is hydrolysis by fatty acid amide hydrolase (FAAH), and inhibitors of the enzyme were suggested as potential treatment for human cannabis dependence. However, the status of brain FAAH in cannabis use disorder is unknown. METHODS Brain FAAH binding was measured with positron emission tomography and [11C]CURB in 22 healthy control subjects and ten chronic cannabis users during early abstinence. The FAAH genetic polymorphism (rs324420) and blood, urine, and hair levels of cannabinoids and metabolites were determined. RESULTS In cannabis users, FAAH binding was significantly lower by 14%-20% across the brain regions examined than in matched control subjects (overall Cohen's d = 0.96). Lower binding was negatively correlated with cannabinoid concentrations in blood and urine and was associated with higher trait impulsiveness. CONCLUSIONS Lower FAAH binding levels in the brain may be a consequence of chronic and recent cannabis exposure and could contribute to cannabis withdrawal. This effect should be considered in the development of novel treatment strategies for cannabis use disorder that target FAAH and endocannabinoids. Further studies are needed to examine possible changes in FAAH binding during prolonged cannabis abstinence and whether lower FAAH binding predates drug use.
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Affiliation(s)
- Isabelle Boileau
- Addiction Imaging Research Group, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Human Brain Lab, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Psychiatry, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada.
| | - Esmaeil Mansouri
- Addiction Imaging Research Group, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Human Brain Lab, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada
| | - Belinda Williams
- Addiction Imaging Research Group, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Human Brain Lab, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada
| | - Bernard Le Foll
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Department Pharmacology & Toxicology, University of Toronto, Toronto, Canada,Department Psychiatry, University of Toronto, Toronto, Canada,Institute of Medical Sciences, University of Toronto, Toronto, Canada
| | - Pablo Rusjan
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Department Psychiatry, University of Toronto, Toronto, Canada
| | - Romina Mizrahi
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Department Psychiatry, University of Toronto, Toronto, Canada,Institute of Medical Sciences, University of Toronto, Toronto, Canada
| | - Rachel F. Tyndale
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Department Pharmacology & Toxicology, University of Toronto, Toronto, Canada,Department Psychiatry, University of Toronto, Toronto, Canada
| | - Marilyn A. Huestis
- Chemistry and Drug Metabolism, IRP, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA
| | - Doris E. Payer
- Addiction Imaging Research Group, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Human Brain Lab, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Department Psychiatry, University of Toronto, Toronto, Canada
| | - Alan A. Wilson
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada
| | - Sylvain Houle
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada
| | - Stephen J. Kish
- Human Brain Lab, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Department Pharmacology & Toxicology, University of Toronto, Toronto, Canada,Department Psychiatry, University of Toronto, Toronto, Canada,Institute of Medical Sciences, University of Toronto, Toronto, Canada
| | - Junchao Tong
- Human Brain Lab, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada,Department Psychiatry, University of Toronto, Toronto, Canada
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25
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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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