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Del Rio R, Serrano RG, Gomez E, Martinez JC, Edward MA, Santos RA, Diaz KS, Cohen-Cory S. Cell-autonomous and differential endocannabinoid signaling impacts the development of presynaptic retinal ganglion cell axon connectivity in vivo. Front Synaptic Neurosci 2023; 15:1176864. [PMID: 37252636 PMCID: PMC10213524 DOI: 10.3389/fnsyn.2023.1176864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 04/25/2023] [Indexed: 05/31/2023] Open
Abstract
Cannabis exposure during gestation evokes significant molecular modifications to neurodevelopmental programs leading to neurophysiological and behavioral abnormalities in humans. The main neuronal receptor for Δ9-tetrahydrocannabinol (THC) is the type-1 cannabinoid receptor CB1R, one of the most abundant G-protein-coupled receptors in the nervous system. While THC is the major psychoactive phytocannabinoid, endocannabinoids (eCBs) are the endogenous ligands of CB1R and are known to act as retrograde messengers to modulate synaptic plasticity at different time scales in the adult brain. Accumulating evidence indicates that eCB signaling through activation of CB1R plays a central role in neural development. During development, most CB1R localized to axons of projection neurons, and in mice eCB signaling impacts axon fasciculation. Understanding of eCB-mediated structural plasticity during development, however, requires the identification of the precise spatial and temporal dynamics of CB1R-mediated modifications at the level of individual neurons in the intact brain. Here, the cell-autonomous role of CB1R and the effects of CB1R-mediated eCB signaling were investigated using targeted single-cell knockdown and pharmacologic treatments in Xenopus. We imaged axonal arbors of retinal ganglion cells (RGCs) in real time following downregulation of CB1R via morpholino (MO) knockdown. We also analyzed RGC axons with altered eCB signaling following treatment with URB597, a selective inhibitor of the enzyme that degrades Anandamide (AEA), or JZL184, an inhibitor of the enzyme that blocks 2-Arachidonoylglycerol (2-AG) hydrolysis, at two distinct stages of retinotectal development. Our results demonstrate that CB1R knockdown impacts RGC axon branching at their target and that differential 2-AG and AEA-mediated eCB signaling contributes to presynaptic structural connectivity at the time that axons terminate and when retinotectal synaptic connections are made. Altering CB1R levels through CB1R MO knockdown similarly impacted dendritic morphology of tectal neurons, thus supporting both pre- and postsynaptic cell-autonomous roles for CB1R-mediated eCB signaling.
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2
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Molecular Landscape of Tourette's Disorder. Int J Mol Sci 2023; 24:ijms24021428. [PMID: 36674940 PMCID: PMC9865021 DOI: 10.3390/ijms24021428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/29/2022] [Accepted: 01/01/2023] [Indexed: 01/12/2023] Open
Abstract
Tourette's disorder (TD) is a highly heritable childhood-onset neurodevelopmental disorder and is caused by a complex interplay of multiple genetic and environmental factors. Yet, the molecular mechanisms underlying the disorder remain largely elusive. In this study, we used the available omics data to compile a list of TD candidate genes, and we subsequently conducted tissue/cell type specificity and functional enrichment analyses of this list. Using genomic data, we also investigated genetic sharing between TD and blood and cerebrospinal fluid (CSF) metabolite levels. Lastly, we built a molecular landscape of TD through integrating the results from these analyses with an extensive literature search to identify the interactions between the TD candidate genes/proteins and metabolites. We found evidence for an enriched expression of the TD candidate genes in four brain regions and the pituitary. The functional enrichment analyses implicated two pathways ('cAMP-mediated signaling' and 'Endocannabinoid Neuronal Synapse Pathway') and multiple biological functions related to brain development and synaptic transmission in TD etiology. Furthermore, we found genetic sharing between TD and the blood and CSF levels of 39 metabolites. The landscape of TD not only provides insights into the (altered) molecular processes that underlie the disease but, through the identification of potential drug targets (such as FLT3, NAALAD2, CX3CL1-CX3CR1, OPRM1, and HRH2), it also yields clues for developing novel TD treatments.
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3
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Khara LS, Ali DW. The endocannabinoid system's involvement in motor development relies on cannabinoid receptors, TRP channels, and Sonic Hedgehog signaling. Physiol Rep 2023; 11:e15565. [PMID: 36636759 PMCID: PMC9837476 DOI: 10.14814/phy2.15565] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 12/04/2022] [Indexed: 06/17/2023] Open
Abstract
The endocannabinoid system (eCS) plays critical roles in locomotor function and motor development; however, the roles of non-canonical cannabinoid receptor systems such as transient receptor potential (TRP) channels and the Sonic Hedgehog (SHH) signaling pathway in conjunction with the eCS in sensorimotor development remains enigmatic. To investigate the involvement of canonical and non-canonical cannabinoid receptors, TRP channels, and the SHH pathway in the development of sensorimotor function in zebrafish, we treated developing animals with pharmacological inhibitors of the CB1R, CB2R, TRPA1/TRPV1/TRPM8, and a smoothened (SMO) agonist, along with inhibitors of the eCS catabolic enzymes fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) during the first ~24 h of zebrafish embryogenesis. Locomotor function was examined by assessing touch-evoked escape swimming at 2 days post-fertilization. We report that FAAH inhibition had no effect on swimming while MAGL inhibition using JZL 184 reduced swimming distance and the dual FAAH/MAGL inhibitor JZL 195 impaired swimming distance and mean swimming velocity. The CB1R antagonist AM 251 prevented locomotor deficits caused by eCS perturbation but the CB2R antagonist AM 630 did not. Inhibition of TRPA1/TRPV1/TRPM8 using AMG 9090 rescued the locomotor reductions caused by FAAH/MAGL inhibition, but not by MAGL inhibition alone. The SMO agonist purmorphamine attenuated the effects of JZL 184 and JZL 195 on swimming distance, but not mean velocity. Together, these findings provide one of the first investigations examining the interactions between the eCS and its non-canonical receptor systems in vertebrate motor development.
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Affiliation(s)
- Lakhan S. Khara
- Department of Biological SciencesUniversity of Alberta EdmontonEdmontonAlbertaCanada
| | - Declan W. Ali
- Department of Biological SciencesUniversity of Alberta EdmontonEdmontonAlbertaCanada
- Department of PhysiologyUniversity of Alberta EdmontonEdmontonAlbertaCanada
- The Neuroscience and Mental Health InstituteUniversity of Alberta EdmontonEdmontonAlbertaCanada
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4
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Chivite M, Comesaña S, Calo J, Soengas JL, Conde-Sieira M. Endocannabinoid receptors are involved in enhancing food intake in rainbow trout. Horm Behav 2022; 146:105277. [PMID: 36356457 DOI: 10.1016/j.yhbeh.2022.105277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 10/17/2022] [Accepted: 10/21/2022] [Indexed: 11/11/2022]
Abstract
The mechanisms involved in hedonic regulation of food intake, including endocannabinoid system (ECs) are scarcely known in fish. We recently demonstrate in rainbow trout the presence of a rewarding response mediated by ECs in hypothalamus and telencephalon when fish fed a lipid-enriched diet, and that central administration of main agonists of ECs namely AEA or 2-AG exert a bimodal effect on feed intake in fish with low doses inducing an increase that disappears with the high dose of both endocannabinoids (EC). To assess the precise involvement of the different receptors of the ECs (CNR1, TRPV1, and GPR55) in this response we injected intracerebroventricularly AEA or 2-AG in the absence/presence of specific receptor antagonists (AM251, capsazepine, and ML193; respectively). The presence of antagonists clearly counteracts the effect of EC supporting the specificity of EC action inducing changes not only in ECs but also in GABA and glutamate metabolism ultimately leading to the increase observed in food intake response.
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Affiliation(s)
- Mauro Chivite
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Sara Comesaña
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Jessica Calo
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - José L Soengas
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Marta Conde-Sieira
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain.
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5
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Bainbridge MN, Mazumder A, Ogasawara D, Abou Jamra R, Bernard G, Bertini E, Burglen L, Cope H, Crawford A, Derksen A, Dure L, Gantz E, Koch-Hogrebe M, Hurst ACE, Mahida S, Marshall P, Micalizzi A, Novelli A, Peng H, Rodriguez D, Robbins SL, Rutledge SL, Scalise R, Schließke S, Shashi V, Srivastava S, Thiffault I, Topol S, Qebibo L, Wieczorek D, Cravatt B, Haricharan S, Torkamani A, Friedman J. Endocannabinoid dysfunction in neurological disease: neuro-ocular DAGLA-related syndrome. Brain 2022; 145:3383-3390. [PMID: 35737950 PMCID: PMC9586540 DOI: 10.1093/brain/awac223] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 05/30/2022] [Indexed: 11/12/2022] Open
Abstract
The endocannabinoid system is a highly conserved and ubiquitous signalling pathway with broad-ranging effects. Despite critical pathway functions, gene variants have not previously been conclusively linked to human disease. We identified nine children from eight families with heterozygous, de novo truncating variants in the last exon of DAGLA with a neuro-ocular phenotype characterized by developmental delay, ataxia and complex oculomotor abnormality. All children displayed paroxysms of nystagmus or eye deviation accompanied by compensatory head posture and worsened incoordination most frequently after waking. RNA sequencing showed clear expression of the truncated transcript and no differences were found between mutant and wild-type DAGLA activity. Immunofluorescence staining of patient-derived fibroblasts and HEK cells expressing the mutant protein showed distinct perinuclear aggregation not detected in control samples. This report establishes truncating variants in the last DAGLA exon as the cause of a unique paediatric syndrome. Because enzymatic activity was preserved, the observed mislocalization of the truncated protein may account for the observed phenotype. Potential mechanisms include DAGLA haploinsufficiency at the plasma membrane or dominant negative effect. To our knowledge, this is the first report directly linking an endocannabinoid system component with human genetic disease and sets the stage for potential future therapeutic avenues.
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Affiliation(s)
- Matthew N Bainbridge
- Rady Children's Institute for Genomic Medicine (RCIGM), San Diego, CA 92123, USA
| | - Aloran Mazumder
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Daisuke Ogasawara
- The Scripps Research Translational Institute, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Rami Abou Jamra
- Institute of Human Genetics, University Medical Center Leipzig, Leipzig 04103, Germany
| | - Geneviève Bernard
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada.,Department of Pediatrics and Human Genetics, McGill University, Montreal, Canada.,Department of Human Genetics, McGill University, Montreal, Canada.,Department Specialized Medicine, Division of Medical Genetics, McGill University Health Center, Montreal, Canada.,Child Health and Human Development Program, Research Institute of the McGill University Health Center, Montreal, Canada
| | - Enrico Bertini
- Unit of Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences 'Bambino Gesu' Children's Research Hospital, IRCCS, Rome, Italy
| | - Lydie Burglen
- Centre de Référence Malformations et Maladies Congénitales du Cervelet, Département de génétique, AP-HP Sorbonne Université, Hôpital Trousseau, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Heidi Cope
- Department of Pediatrics, Division Medical Genetics Durham, Duke University Medical Center, North Carolina, USA
| | | | - Alexa Derksen
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada.,Child Health and Human Development Program, Research Institute of the McGill University Health Center, Montreal, Canada
| | - Leon Dure
- Division of Pediatric Neurology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Emily Gantz
- Division of Pediatric Neurology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | | | - Anna C E Hurst
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Sonal Mahida
- Department of Neurology, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Paige Marshall
- Department of Neurology, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Alessia Micalizzi
- Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, Roma, Italy
| | - Antonio Novelli
- Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, Roma, Italy
| | - Hongfan Peng
- The Scripps Research Translational Institute, The Scripps Research Institute, La Jolla, CA 92037, USA
| | | | - Diana Rodriguez
- Sorbonne Université, INSERM UMR 1141, AP-HP.SU, Centre de Référence Maladies Rares Malformations et Maladies Congénitales du Cervelet & Service de Neuropédiatrie, Hôpital Trousseau, Paris, France
| | - Shira L Robbins
- Ratner Children's Eye Center at the Shiley Eye Institute; Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA 92093, USA
| | - S Lane Rutledge
- Division of Pediatric Neurology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL 35233, USA.,Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Roberta Scalise
- Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Pisa, Italy.,Tuscan PhD Program of Neuroscience, University of Florence, Pisa and Siena, Florence, Italy
| | - Sophia Schließke
- Institute of Human Genetics, University Medical Center Leipzig, Leipzig 04103, Germany
| | - Vandana Shashi
- Department of Pediatrics, Division Medical Genetics Durham, Duke University Medical Center, North Carolina, USA
| | | | - Isabella Thiffault
- Genomic Medicine Center, Children's Mercy Hospital, Kansas City, Missouri, USA.,Faculty of Medicine, University of Missouri Kansas City, Kansas City, Missouri, USA.,Department of Pathology, Children's Mercy Hospital, Kansas City, Missouri, USA
| | - Sarah Topol
- The Scripps Research Translational Institute, The Scripps Research Institute, La Jolla, CA 92037, USA
| | | | - Leila Qebibo
- Centre de Référence Malformations et Maladies Congénitales du Cervelet, Département de génétique, AP-HP Sorbonne Université, Hôpital Trousseau, Paris, France
| | - Dagmar Wieczorek
- Institute of Human Genetics, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, 40225, Düsseldorf, Germany
| | - Benjamin Cravatt
- The Scripps Research Translational Institute, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Svasti Haricharan
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Ali Torkamani
- The Scripps Research Translational Institute, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Jennifer Friedman
- Rady Children's Institute for Genomic Medicine (RCIGM), San Diego, CA 92123, USA.,Division of Neurology, Rady Children's Hospital San Diego, CA 92123, USA.,Department of Neurosciences, University of California La Jolla, CA 92037, USA.,Department of Pediatrics, University of California La Jolla, CA 92037, USA
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6
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Khara LS, Amin MR, Ali DW. Inhibiting the endocannabinoid degrading enzymes FAAH and MAGL during zebrafish embryogenesis alters sensorimotor function. J Exp Biol 2022; 225:275080. [PMID: 35438163 DOI: 10.1242/jeb.244146] [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: 02/19/2022] [Accepted: 04/07/2022] [Indexed: 11/20/2022]
Abstract
The endocannabinoid system (eCS) plays a critical role in a variety of homeostatic and developmental processes. Although the eCS is known to be involved in motor and sensory function, the role of endocannabinoid (eCB) signaling in sensorimotor development remains to be fully understood. In this study, the catabolic enzymes fatty acid amide hydrolase (FAAH), and monoacylglycerol lipase (MAGL) were inhibited either simultaneously, or individually during the first ∼24 hours of zebrafish embryogenesis, and the properties of contractile events and escape responses were studied in animals ranging in age from 1 day post fertilization (dpf) to 10 weeks. This perturbation of the eCS resulted in alterations to contractile activity at 1 dpf. Inhibition of MAGL using JZL 184 and dual inhibition of FAAH/MAGL using JZL 195 decreased escape swimming activity at 2 dpf. Treatment with JZL 195 also produced alterations in the properties of the 2 dpf short latency C-start escape response. Animals treated with JZL 195 exhibited deficits in escape responses elicited by auditory/vibrational (A/V) stimuli at 5 and 6 dpf. These deficits were also present during the juvenile developmental stage (8-10-week-old fish), demonstrating a prolonged impact to sensory systems. These findings demonstrate that eCS perturbation affects sensorimotor function, and underscores the importance of eCB signaling in the development of motor and sensory processes.
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Affiliation(s)
- Lakhan S Khara
- Departments of Biological Sciences, CW-405 Biological Sciences Building, University of Alberta Edmonton, Alberta T6G 2E9, Canada
| | - Md Ruhul Amin
- Pharmacology, CW-405 Biological Sciences Building, University of Alberta Edmonton, Alberta T6G 2E9, Canada
| | - Declan W Ali
- Departments of Biological Sciences, CW-405 Biological Sciences Building, University of Alberta Edmonton, Alberta T6G 2E9, Canada.,Physiology, CW-405 Biological Sciences Building, University of Alberta Edmonton, Alberta T6G 2E9, Canada.,Neuroscience and Mental Health Institute. CW-405 Biological Sciences Building, University of Alberta Edmonton, Alberta T6G 2E9, Canada
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7
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Sufian MS, Amin MR, Ali DW. Early suppression of the endocannabinoid degrading enzymes FAAH and MAGL alters locomotor development in zebrafish. J Exp Biol 2021; 224:271961. [DOI: 10.1242/jeb.242635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 06/15/2021] [Indexed: 11/20/2022]
Abstract
ABSTRACT
The fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) enzymes are the predominant catabolic regulators of the major endocannabinoids (eCBs) anadamide (AEA) and 2-arachidonoylglycerol (2-AG), respectively. The expression and roles of eCBs during early embryogenesis remain to be fully investigated. Here, we inhibited FAAH and MAGL in zebrafish embryos during the first 24 h of life and examined motor neuron and locomotor development at 2 and 5 days post fertilization (dpf). Application of the dual FAAH/MAGL inhibitor, JZL195 (2 µmol l−1), resulted in a reduction in primary and secondary motor neuron axonal branching. JZL195 also reduced nicotinic acetylcholine receptor (nAChR) expression at neuromuscular junctions. Application of URB597 (5 µmol l−1), a specific inhibitor of the FAAH enzyme, also decreased primary motor neuron branching but did not affect secondary motor neuron branching and nAChR expression. Interestingly, JZL184 (5 µmol l−1), a specific inhibitor of MAGL, showed no effects on motor neuron branching or nAChR expression. Co-treatment of the enzyme inhibitors with the CB1R inhibitor AM251 confirmed the involvement of CB1R in motor neuron branching. Disruption of FAAH or MAGL reduced larval swimming activity, and AM251 attenuated the JZL195- and URB597-induced locomotor changes, but not the effects of JZL184. Together, these findings indicate that inhibition of FAAH, or augmentation of AEA acting through CB1R during early development, may be responsible for locomotor deficiencies.
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Affiliation(s)
- M. Shah Sufian
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - M. Ruhul Amin
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Declan W. Ali
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
- Department of Physiology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
- Neuroscience and Mental Health Institute, University of Alberta, 2-132 Li Ka Shing Centre for Health Research Innovation, Edmonton, Alberta, T6G 2E1, Canada
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8
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Díaz-Rúa A, Chivite M, Comesaña S, Velasco C, Soengas JL, Conde-Sieira M. Central administration of endocannabinoids exerts bimodal effects in food intake of rainbow trout. Horm Behav 2021; 134:105021. [PMID: 34242873 DOI: 10.1016/j.yhbeh.2021.105021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/28/2021] [Accepted: 06/22/2021] [Indexed: 10/20/2022]
Abstract
The endocannabinoid system (ECs) is known to participate in several processes in mammals related to synaptic signaling including regulation of food intake, appetite and energy balance. In fish, the relationship of ECs with food intake regulation is poorly understood. In the present study, we assessed in rainbow trout Oncorhynchus mykiss the effect of intracerebroventricular administration (ICV) of low and high doses of the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG) on food intake. We assessed endocannabinoid levels in hypothalamus, telencephalon and plasma as well as the effect of AEA and 2-AG administration at central level on gene expression of receptors involved in ECs (cnr1, gpr55 and trpv1) and markers of neural activity (fos, ntrk2 and GABA-related genes). The results obtained indicate that whereas high doses of endocannabinoids did not elicit changes in food intake levels, low doses of the endocannabinoids produce an orexigenic effect that could be due to a possible inhibition of gabaergic neurotransmission and the modulation of neural plasticity in brain areas related to appetite control, such as hypothalamus and telencephalon.
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Affiliation(s)
- Adrián Díaz-Rúa
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Mauro Chivite
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Sara Comesaña
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Cristina Velasco
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain; CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Terminal de Cruzeiros do Porto de Leixões, Av.General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal
| | - José L Soengas
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Marta Conde-Sieira
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain.
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9
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Díaz-Rúa A, Chivite M, Velasco C, Comesaña S, Soengas JL, Conde-Sieira M. Periprandial response of central cannabinoid system to different feeding conditions in rainbow trout Oncorhynchus mykiss. Nutr Neurosci 2020; 25:1265-1276. [DOI: 10.1080/1028415x.2020.1853412] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Adrián Díaz-Rúa
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
| | - Mauro Chivite
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
| | - Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
| | - Sara Comesaña
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
| | - José L. Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
| | - Marta Conde-Sieira
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
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10
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Cannabinoids affect the mouse visual acuity via the cannabinoid receptor type 2. Sci Rep 2020; 10:15819. [PMID: 32978469 PMCID: PMC7519129 DOI: 10.1038/s41598-020-72553-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 09/02/2020] [Indexed: 12/18/2022] Open
Abstract
Recently, there have been increasing indications that the endocannabinoid (eCB) system is involved in vision. Multiple research teams studied the cannabinoid receptor type 2 (CB2R) expression and function in the mouse retina. Here, we examined the consequence of CB2R modulation on visual acuity using genetic and pharmacologic tools. We found that Cnr2 knockout mice show an enhanced visual acuity, CB2R activation decreased visual acuity while CB2R blockade with the inverse agonist AM630 increased it. The inhibition of 2-arachidonylglycerol (2-AG) synthesis and degradation also greatly increased and decreased visual acuity, respectively. No differences were seen when the cannabinoid receptor type 1 (CB1R) was deleted, blocked or activated implying that CB2R exclusively mediates cannabinoid modulation of the visual acuity. We also investigated the role of cannabinoids in retinal function using electroretinography (ERG). We found that modulating 2-AG levels affected many ERG components, such as the a-wave and oscillatory potentials (OPs), suggesting an impact on cones and amacrine cells. Taken together, these results reveal that CB2R modulates visual acuity and that eCBs such as 2-AG can modulate both visual acuity and retinal sensitivity. Finally, these findings establish that CB2R is present in visual areas and regulates vision-related functions.
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Díaz-Rúa A, Chivite M, Comesaña S, Velasco C, Valente LMP, Soengas JL, Conde-Sieira M. The endocannabinoid system is affected by a high-fat-diet in rainbow trout. Horm Behav 2020; 125:104825. [PMID: 32771417 DOI: 10.1016/j.yhbeh.2020.104825] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/21/2020] [Accepted: 07/23/2020] [Indexed: 01/07/2023]
Abstract
The endocannabinoid system (ECs) is a well known contributor to the hedonic regulation of food intake (FI) in mammals whereas in fish, the knowledge regarding hedonic mechanisms that control FI is limited. Previous studies reported the involvement of ECs in FI regulation in fish since anandamide (AEA) treatment induced enhanced FI and changes of mRNA abundance of appetite-related neuropeptides through cannabinoid receptor 1 (cnr1). However, no previous studies in fish evaluated the impact of palatable food like high-fat diets (HFD) on mechanisms involved in hedonic regulation of FI including the possible involvement of ECs. Therefore, we aimed to evaluate the effect of feeding a HFD on the response of ECs in rainbow trout (Oncorhynchus mykiss). First, we demonstrated a higher intake over 4 days of HFD compared with a control diet (CD). Then, we evaluated the postprandial response (1, 3 and 6 h) of components of the ECs in plasma, hypothalamus, and telencephalon after feeding fish with CD and HFD. The results obtained indicate that the increased FI of HFD occurred along with increased levels of 2-arachidonoylglycerol (2-AG) and AEA in plasma and in brain areas like hypothalamus and telencephalon putatively involved in hedonic regulation of FI in fish. Decreased mRNA abundance of EC receptors like cnr1, gpr55 and trpv1 suggest a feed-back counter-regulatory mechanism in response to the increased levels of EC. Furthermore, the results also suggest that neural activity players associated to FI regulation in mammals as cFOS, γ-Amino butyric acid (GABA) and brain derived neurotrophic factor (BDNF)/neurotrophic receptor tyrosine kinase (NTRK) systems could be involved in the hedonic eating response to a palatable diet in fish.
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Affiliation(s)
- Adrián Díaz-Rúa
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Spain
| | - Mauro Chivite
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Spain
| | - Sara Comesaña
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Spain
| | - Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Spain
| | - Luisa M P Valente
- CIIMAR/CIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Terminal de Cruzeiros do Porto de Leixões. Av. General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal; ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Spain
| | - Marta Conde-Sieira
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Spain.
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12
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Marijuana and Opioid Use during Pregnancy: Using Zebrafish to Gain Understanding of Congenital Anomalies Caused by Drug Exposure during Development. Biomedicines 2020; 8:biomedicines8080279. [PMID: 32784457 PMCID: PMC7460517 DOI: 10.3390/biomedicines8080279] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 08/03/2020] [Accepted: 08/06/2020] [Indexed: 01/09/2023] Open
Abstract
Marijuana and opioid addictions have increased alarmingly in recent decades, especially in the United States, posing threats to society. When the drug user is a pregnant mother, there is a serious risk to the developing baby. Congenital anomalies are associated with prenatal exposure to marijuana and opioids. Here, we summarize the current data on the prevalence of marijuana and opioid use among the people of the United States, particularly pregnant mothers. We also summarize the current zebrafish studies used to model and understand the effects of these drug exposures during development and to understand the behavioral changes after exposure. Zebrafish experiments recapitulate the drug effects seen in human addicts and the birth defects seen in human babies prenatally exposed to marijuana and opioids. Zebrafish show great potential as an easy and inexpensive model for screening compounds for their ability to mitigate the drug effects, which could lead to new therapeutics.
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13
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Interference with the Cannabinoid Receptor CB1R Results in Miswiring of GnRH3 and AgRP1 Axons in Zebrafish Embryos. Int J Mol Sci 2019; 21:ijms21010168. [PMID: 31881740 PMCID: PMC6982252 DOI: 10.3390/ijms21010168] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 12/18/2019] [Accepted: 12/20/2019] [Indexed: 12/19/2022] Open
Abstract
The G protein-coupled cannabinoid receptors type 1 (CB1R) and type 2 (CB2R), and their endocannabinoid (eCBs) ligands, have been implicated in several aspects of brain wiring during development. Here we aim to assess whether interfering with CB1R affects development, neuritogenesis and pathfinding of GnRH and AgRP neurons, forebrain neurons that control respectively reproduction and appetite. We pharmacologically and genetically interfered with CB1R in zebrafish strains with fluorescently labeled GnRH3 and the AgRP1 neurons. By applying CB1R antagonists we observed a reduced number of GnRH3 neurons, fiber misrouting and altered fasciculation. Similar phenotypes were observed by CB1R knockdown. Interfering with CB1R also resulted in a reduced number, misrouting and poor fasciculation of the AgRP1 neuron’s axonal projections. Using a bioinformatic approach followed by qPCR validation, we have attempted to link CB1R functions with known guidance and fasciculation proteins. The search identified stathmin-2, a protein controlling microtubule dynamics, previously demonstrated to be coexpressed with CB1R and now shown to be downregulated upon interference with CB1R in zebrafish. Together, these results raise the likely possibility that embryonic exposure to low doses of CB1R-interfering compounds could impact on the development of the neuroendocrine systems controlling sexual maturation, reproduction and food intake.
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14
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Sufian MS, Amin MR, Kanyo R, Allison WT, Ali DW. CB 1 and CB 2 receptors play differential roles in early zebrafish locomotor development. ACTA ACUST UNITED AC 2019; 222:jeb.206680. [PMID: 31253713 DOI: 10.1242/jeb.206680] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 06/19/2019] [Indexed: 12/22/2022]
Abstract
Endocannabinoids (eCBs) mediate their effects through actions on several receptors, including the cannabinoid receptors CB1R and CB2R. The role played by eCBs in the development of locomotor systems is not fully understood. In this study, we investigated the roles of the eCB system in zebrafish development by pharmacologically inhibiting CB1R and CB2R (with AM251 and AM630, respectively) in either the first or second day of development. We examined the morphology of motor neurons and we determined neuromuscular outputs by quantifying the amount of swimming in 5 days post-fertilization larvae. Blocking CB2R during the first day of development resulted in gross morphological deficits and reductions in heart rate that were greater than those following treatment with the CB1R blocker AM251. Blocking CB1Rs from 0 to 24 h post-fertilization resulted in an increase in the number of secondary and tertiary branches of primary motor neurons, whereas blocking CB2Rs had the opposite effect. Both treatments manifested in reduced levels of swimming. Additionally, blocking CB1Rs resulted in greater instances of non-inflated and partially inflated swim bladders compared with AM630 treatment, suggesting that at least some of the deficits in locomotion may result from an inability to adjust buoyancy. Together, these findings indicate that the eCB system is pivotal to the development of the locomotor system in zebrafish, and that perturbations of the eCB system early in life may have detrimental effects.
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Affiliation(s)
- Md Shah Sufian
- Department of Biological Sciences, CW-405 Biological Sciences Building, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | - Md Ruhul Amin
- Department of Biological Sciences, CW-405 Biological Sciences Building, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | - Richard Kanyo
- Department of Biological Sciences, CW-405 Biological Sciences Building, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9.,Neuroscience and Mental Health Institute, CW-405 Biological Sciences Building, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | - W Ted Allison
- Department of Biological Sciences, CW-405 Biological Sciences Building, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9.,Neuroscience and Mental Health Institute, CW-405 Biological Sciences Building, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | - Declan W Ali
- Department of Biological Sciences, CW-405 Biological Sciences Building, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9 .,Neuroscience and Mental Health Institute, CW-405 Biological Sciences Building, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9.,Department of Physiology, CW-405 Biological Sciences Building, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
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15
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Boa-Amponsem O, Zhang C, Mukhopadhyay S, Ardrey I, Cole GJ. Ethanol and cannabinoids interact to alter behavior in a zebrafish fetal alcohol spectrum disorder model. Birth Defects Res 2019; 111:775-788. [PMID: 30648819 DOI: 10.1002/bdr2.1458] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 12/21/2018] [Accepted: 01/03/2019] [Indexed: 01/05/2023]
Abstract
BACKGROUND Recent work suggests that endocannabinoids (eCBs) may signal through the sonic hedgehog signaling pathway. We therefore hypothesized that combined ethanol and eCB exposure during defined stages of zebrafish embryogenesis will produce deficits comparable to human fetal alcohol spectrum disorder (FASD). METHODS Zebrafish embryos were exposed to ethanol or cannabinoid agonists alone or in combination at defined developmental stages and assessed for changes in brain morphology or expression of marker genes such as pax6a. Juvenile fish were then assessed for risk-taking/anxiety-like behavior using the novel tank dive test. RESULTS Either chronic or acute exposure to high doses of the CB1R agonist ACEA resulted in FASD phenotypes. However, acute subthreshold doses of CB1R agonist alone, or combined with 0.5% ethanol, did not induce morphological phenotypes, but did induce dysmorphogenesis when combined with acute 1% ethanol. Phenotypes were rescued using the CB1R antagonist SR141716A. In addition, JZL195, a dual inhibitor of FAAH and MAGL, two degradative enzymes for eCBs, induced FASD phenotypes in the presence of subthreshold ethanol, confirming the activation of common signaling pathways by ethanol and eCBs. We next analyzed the effects of ethanol and CB1R agonist on juvenile zebrafish behavior and show that ACEA or ethanol alone did not alter behavior, but combined ACEA and ethanol increased risk-taking behavior. CONCLUSIONS These studies demonstrate that pathological and behavioral phenotypes associated with FASD are induced by exposure to CB1R agonists and suggest that combined exposure to lower levels of alcohol and marijuana may be capable of inducing FASD-like morphological and behavioral impairments.
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Affiliation(s)
- Oswald Boa-Amponsem
- Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, North Carolina.,Integrated Biosciences Program, North Carolina Central University, Durham, North Carolina
| | - Chengjin Zhang
- Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, North Carolina
| | - Somnath Mukhopadhyay
- Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, North Carolina.,Department of Chemistry and Biochemistry, North Carolina Central University, Durham, North Carolina
| | - Iman Ardrey
- Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, North Carolina.,Department of Biological and Biomedical Sciences, North Carolina Central University, Durham, North Carolina
| | - Gregory J Cole
- Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, North Carolina.,Department of Biological and Biomedical Sciences, North Carolina Central University, Durham, North Carolina
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16
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Functional characterization of the cannabinoid receptors 1 and 2 in zebrafish larvae using behavioral analysis. Psychopharmacology (Berl) 2019; 236:2049-2058. [PMID: 30820632 PMCID: PMC6647118 DOI: 10.1007/s00213-019-05193-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 02/07/2019] [Indexed: 12/30/2022]
Abstract
RATIONALE The endocannabinoid system (ECS) comprises the cannabinoids anandamide and 2-arachidonoylglycerol and the cannabinoid receptors 1 and 2 (Cnr1 and Cnr2). The function of these receptors in relation to zebrafish larval behavior is poorly understood, even though the zebrafish larva has become a versatile animal model in biomedical research. OBJECTIVES The objective of the present study is to characterize the function of Cnr1 and Cnr2 in relation to behavior in zebrafish. METHODS Behavioral analysis of zebrafish larvae was performed using a visual motor response (VMR) test, which allows locomotor activity to be determined under basal conditions and upon a dark challenge. RESULTS Treatment with the non-specific Cnr agonists WIN55,212-2 and CP55,940 resulted in a decrease in locomotion. This was observed for both basal and challenge-induced locomotion, although the potency for these two effects was different, which suggests different mechanisms of action. In addition, WIN55,212-2 increased the reaction time of the startle response after the dark challenge. Using the Cnr1 antagonist AM251 and a cnr1-/- mutant line, it was shown that the effects were mediated by Cnr1 and not Cnr2. Interestingly, administration of the antagonist AM251 alone does not have an effect on locomotion, which indicates that endogenous cannabinoid activity does not affect locomotor activity of zebrafish larvae. Upon repeated dark challenges, the WIN55,212-2 effect on the locomotor activity decreased, probably due to desensitization of Cnr1. CONCLUSIONS Taken together, these results show that Cnr1 activation by exogenous endocannabinoids modulates both basal and challenge-induced locomotor activity in zebrafish larvae and that these behavioral effects can be used as a readout to monitor the Cnr1 responsiveness in the zebrafish larva model system.
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17
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Motor neuron development in zebrafish is altered by brief (5-hr) exposures to THC (∆ 9-tetrahydrocannabinol) or CBD (cannabidiol) during gastrulation. Sci Rep 2018; 8:10518. [PMID: 30002406 PMCID: PMC6043604 DOI: 10.1038/s41598-018-28689-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 06/26/2018] [Indexed: 12/11/2022] Open
Abstract
Marijuana is one of the most commonly used illicit recreational drugs and is widely used for medicinal purposes. The psychoactive ingredient in marijuana is ∆9-tetrahydrocannabinol (∆9-THC), whereas the major non-psychoactive ingredient is cannabidiol (CBD). Here, we exposed zebrafish embryos to ∆9-THC or CBD for 5 hours during the critical stage of development known as gastrulation. Embryos were allowed to develop normally and were examined at 2 and 5 days post fertilization. THC and CBD treated embryos exhibited reduced heart rates, axial malformations and shorter trunks. Cannabinoid treatment altered synaptic activity at neuromuscular junctions (NMJs), and fluorescent labelling of primary and secondary motor neurons indicated a change in branching patterns and a reduction in the number of axonal branches in the trunk musculature. Furthermore, there were alterations in the α-bungarotoxin labelling of nicotinic acetylcholine receptors at NMJs. Locomotion studies show that larvae exposed to THC or CBD during gastrulation exhibited drastic reductions in the number of C-start escape responses to sound stimuli, but not to touch stimuli. Together these findings indicate that zebrafish embryos exposed to ∆9-THC or CBD during the brief but critical period of gastrulation exhibited alterations in heart rate, motor neuronal morphology, synaptic activity at the NMJ and locomotor responses to sound.
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18
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Krug RG, Lee HB, El Khoury LY, Sigafoos AN, Petersen MO, Clark KJ. The endocannabinoid gene faah2a modulates stress-associated behavior in zebrafish. PLoS One 2018; 13:e0190897. [PMID: 29304078 PMCID: PMC5756047 DOI: 10.1371/journal.pone.0190897] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 12/21/2017] [Indexed: 11/18/2022] Open
Abstract
The ability to orchestrate appropriate physiological and behavioral responses to stress is important for survival, and is often dysfunctional in neuropsychiatric disorders that account for leading causes of global disability burden. Numerous studies have shown that the endocannabinoid neurotransmitter system is able to regulate stress responses and could serve as a therapeutic target for the management of these disorders. We used quantitative reverse transcriptase-polymerase chain reactions to show that genes encoding enzymes that synthesize (abhd4, gde1, napepld), enzymes that degrade (faah, faah2a, faah2b), and receptors that bind (cnr1, cnr2, gpr55-like) endocannabinoids are expressed in zebrafish (Danio rerio). These genes are conserved in many other vertebrates, including humans, but fatty acid amide hydrolase 2 has been lost in mice and rats. We engineered transcription activator-like effector nucleases to create zebrafish with mutations in cnr1 and faah2a to test the role of these genes in modulating stress-associated behavior. We showed that disruption of cnr1 potentiated locomotor responses to hyperosmotic stress. The increased response to stress was consistent with rodent literature and served to validate the use of zebrafish in this field. Moreover, we showed for the first time that disruption of faah2a attenuated the locomotor responses to hyperosmotic stress. This later finding suggests that FAAH2 may be an important mediator of stress responses in non-rodent vertebrates. Accordingly, FAAH and FAAH2 modulators could provide distinct therapeutic options for stress-aggravated disorders.
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Affiliation(s)
- Randall G. Krug
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States of America
- Mayo Clinic Graduate School of Biomedical Sciences (Neurobiology of Disease Track), Mayo Clinic, Rochester, MN, United States of America
- Mayo Clinic School of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Han B. Lee
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States of America
- Mayo Clinic Graduate School of Biomedical Sciences (Neurobiology of Disease Track), Mayo Clinic, Rochester, MN, United States of America
| | - Louis Y. El Khoury
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States of America
| | - Ashley N. Sigafoos
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States of America
| | - Morgan O. Petersen
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States of America
| | - Karl J. Clark
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States of America
- * E-mail:
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19
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Smith DR, Stanley CM, Foss T, Boles RG, McKernan K. Rare genetic variants in the endocannabinoid system genes CNR1 and DAGLA are associated with neurological phenotypes in humans. PLoS One 2017; 12:e0187926. [PMID: 29145497 PMCID: PMC5690672 DOI: 10.1371/journal.pone.0187926] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 10/27/2017] [Indexed: 12/24/2022] Open
Abstract
Rare genetic variants in the core endocannabinoid system genes CNR1, CNR2, DAGLA, MGLL and FAAH were identified in molecular testing data from 6,032 patients with a broad spectrum of neurological disorders. The variants were evaluated for association with phenotypes similar to those observed in the orthologous gene knockouts in mice. Heterozygous rare coding variants in CNR1, which encodes the type 1 cannabinoid receptor (CB1), were found to be significantly associated with pain sensitivity (especially migraine), sleep and memory disorders—alone or in combination with anxiety—compared to a set of controls without such CNR1 variants. Similarly, heterozygous rare variants in DAGLA, which encodes diacylglycerol lipase alpha, were found to be significantly associated with seizures and neurodevelopmental disorders, including autism and abnormalities of brain morphology, compared to controls. Rare variants in MGLL, FAAH and CNR2 were not associated with any neurological phenotypes in the patients tested. Diacylglycerol lipase alpha synthesizes the endocannabinoid 2-AG in the brain, which interacts with CB1 receptors. The phenotypes associated with rare CNR1 variants are reminiscent of those implicated in the theory of clinical endocannabinoid deficiency syndrome. The severe phenotypes associated with rare DAGLA variants underscore the critical role of rapid 2-AG synthesis and the endocannabinoid system in regulating neurological function and development. Mapping of the variants to the 3D structure of the type 1 cannabinoid receptor, or primary structure of diacylglycerol lipase alpha, reveals clustering of variants in certain structural regions and is consistent with impacts to function.
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Affiliation(s)
- Douglas R. Smith
- Courtagen Life Sciences, Inc., Woburn, MA, United States of America
- * E-mail:
| | | | - Theodore Foss
- Courtagen Life Sciences, Inc., Woburn, MA, United States of America
| | - Richard G. Boles
- Courtagen Life Sciences, Inc., Woburn, MA, United States of America
| | - Kevin McKernan
- Courtagen Life Sciences, Inc., Woburn, MA, United States of America
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Oltrabella F, Melgoza A, Nguyen B, Guo S. Role of the endocannabinoid system in vertebrates: Emphasis on the zebrafish model. Dev Growth Differ 2017; 59:194-210. [PMID: 28516445 DOI: 10.1111/dgd.12351] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 03/18/2017] [Accepted: 03/24/2017] [Indexed: 12/15/2022]
Abstract
The endocannabinoid system (eCBs), named after the plant Cannabis sativa, comprises cannabinoid receptors, endogenous ligands known as "endocannabinoids", and enzymes involved in the biosynthesis and degradation of these ligands, as well as putative transporters for these ligands. ECBs proteins and small molecules have been detected in early embryonic stages of many vertebrate models. As a result, cannabinoid receptors and endogenous as well as exogenous cannabinoids influence development and behavior in many vertebrate species. Understanding the precise mechanisms of action for the eCBs will provide an invaluable guide towards elucidation of vertebrate development and will also help delineate how developmental exposure to marijuana might impact health and cognitive/executive functioning in adulthood. Here we review the developmental roles of the eCBs in vertebrates, focusing our attention on the zebrafish model. Since little is known regarding the eCBs in zebrafish, we provide new data on the expression profiles of eCBs genes during development and in adult tissue types of this model organism. We also highlight exciting areas for future investigations, including the synaptic regulation of eCBs, its role in reward and addiction, and in nervous system development and plasticity.
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Affiliation(s)
- Francesca Oltrabella
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, 94158-2811, USA
| | - Adam Melgoza
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, 94158-2811, USA.,Pharmaceutical Sciences and Pharmacogenomics Graduate Program, University of California, San Francisco, California, 94158-2811, USA
| | - Brian Nguyen
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, 94158-2811, USA.,Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California, 94720-3104, USA
| | - Su Guo
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, 94158-2811, USA.,Pharmaceutical Sciences and Pharmacogenomics Graduate Program, University of California, San Francisco, California, 94158-2811, USA.,Institute for Human Genetics, University of California, San Francisco, California, 94158-2811, USA
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