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O'Donohue MP, Amir Hamzah K, Nichols D, Ney LJ. Trauma film viewing and intrusive memories: Relationship between salivary alpha amylase, endocannabinoids, and cortisol. Psychoneuroendocrinology 2024; 164:107007. [PMID: 38503195 DOI: 10.1016/j.psyneuen.2024.107007] [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: 11/13/2023] [Revised: 01/14/2024] [Accepted: 02/26/2024] [Indexed: 03/21/2024]
Abstract
The endogenous cannabinoid (ECB) system is a small molecule lipid signalling system that is involved in stress response activation and is associated with PTSD, but it is unclear whether salivary ECBs are part of the sympathetic nervous system response to stress. We conducted an adapted trauma film paradigm, where participants completed a cold pressor test (or control) while watching a 10-minute trauma film. We also collected saliva and hair samples and tested them for ECBs, cortisol, and salivary alpha amylase (sAA). As hypothesised, there were significant positive correlations between sAA activity and salivary ECB levels, particularly 2-arachidonoyl glycerol (2-AG), though ECBs were not correlated with sAA stress reactivity. Participants who had a significant cortisol response to the trauma film/stressor reported less intrusive memories, which were also less distressing and less vivid. This effect was moderated by arachidonoyl ethanolamide (AEA), where decreases in AEA post-stress were associated with more intrusive memories in cortisol non-responders only. This study provides new evidence for the role of ECBs in the sympathetic nervous system.
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Affiliation(s)
- Matthew P O'Donohue
- School of Psychology and Counselling, Queensland University of Technology, Australia
| | - Khalisa Amir Hamzah
- School of Psychology and Counselling, Queensland University of Technology, Australia
| | - David Nichols
- Central Science Laboratory, University of Tasmania, Australia
| | - Luke J Ney
- School of Psychology and Counselling, Queensland University of Technology, Australia.
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Gowatch LC, Evanski JM, Ely SL, Zundel CG, Bhogal A, Carpenter C, Shampine MM, O'Mara E, Mazurka R, Barcelona J, Mayo LM, Marusak HA. Endocannabinoids and Stress-Related Neurospsychiatric Disorders: A Systematic Review and Meta-Analysis of Basal Concentrations and Response to Acute Psychosocial Stress. Cannabis Cannabinoid Res 2024. [PMID: 38683635 DOI: 10.1089/can.2023.0246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024] Open
Abstract
Background: Dysregulation of the endocannabinoid (eCB) system is implicated in various stress-related neuropsychiatric disorders (SRDs), including anxiety, depression, and post-traumatic stress disorder (PTSD). In this systematic review and meta-analysis, our objectives were to characterize circulating anandamide (AEA) and 2-arachidonoylglycerol (2-AG) concentrations at rest and in response to acute laboratory-based psychosocial stress in individuals with SRDs and without (controls). Our primary aims were to assess the effects of acute psychosocial stress on eCB concentrations in controls (Aim 1), compare baseline (prestress) eCB concentrations between individuals with SRDs and controls (Aim 2), and explore differential eCB responses to acute psychosocial stress in individuals with SRDs compared with controls (Aim 3). Methods: On June 8, 2023, a comprehensive review of the MEDLINE (PubMed) database was conducted to identify original articles meeting inclusion criteria. A total of 1072, 1341, and 400 articles were screened for inclusion in Aims 1, 2, and 3, respectively. Results: Aim 1, comprised of seven studies in controls, revealed that most studies reported stress-related increases in AEA (86%, with 43% reporting statistical significance) and 2-AG (83%, though none were statistically significant except for one study in saliva). However, meta-analyses did not support these patterns (p's>0.05). Aim 2, with 20 studies, revealed that most studies reported higher baseline concentrations of both AEA (63%, with 16% reporting statistical significance) and 2-AG (60%, with 10% reporting statistical significance) in individuals with SRDs compared with controls. Meta-analyses confirmed these findings (p's<0.05). Aim 3, which included three studies, had only one study that reported statistically different stress-related changes in 2-AG (but not AEA) between individuals with PTSD (decrease) and controls (increase), which was supported by the meta-analysis (p<0.001). Meta-analyses showed heterogeneity across studies and aims (I2=14-97%). Conclusion: Despite substantial heterogeneity in study characteristics, samples, and methodologies, consistent patterns emerged, including elevated baseline AEA and 2-AG in individuals with SRDs compared with controls, as well as smaller stress-related increases in 2-AG in individuals with SRDs compared with controls. To consider eCBs as reliable biomarkers and potential intervention targets for SRDs, standardized research approaches are needed to clarify the complex relationships between eCBs, SRDs, and psychosocial stress.
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Affiliation(s)
- Leah C Gowatch
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, Michigan, USA
| | - Julia M Evanski
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Samantha L Ely
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, Michigan, USA
- Translational Neuroscience PhD Program, Wayne State University, Detroit, Michigan, USA
| | - Clara G Zundel
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, Michigan, USA
| | - Amanpreet Bhogal
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, Michigan, USA
| | - Carmen Carpenter
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, Michigan, USA
| | - MacKenna M Shampine
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, Michigan, USA
| | - Emilie O'Mara
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, Michigan, USA
| | - Raegan Mazurka
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
- Nova Scotia Health, Halifax, Nova Scotia, Canada
| | - Jeanne Barcelona
- Center for Health and Community Impact, College of Education, Wayne State University, Detroit, Michigan, USA
| | - Leah M Mayo
- Hotchkiss Brain Institute and Department of Psychiatry, University of Calgary, Calgary, Alberta, Canada
| | - Hilary A Marusak
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, Michigan, USA
- Translational Neuroscience PhD Program, Wayne State University, Detroit, Michigan, USA
- Department of Pharmacology, Wayne State University, Detroit, Michigan, USA
- Merrill Palmer Skillman Institute for Child and Family Development, Wayne State University, Detroit, Michigan, USA
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Kwee CMB, van der Flier FE, Duits P, van Balkom AJLM, Cath DC, Baas JMP. Effects of cannabidiol on fear conditioning in anxiety disorders: decreased threat expectation during retention, but no enhanced fear re-extinction. Psychopharmacology (Berl) 2024; 241:833-847. [PMID: 38044339 DOI: 10.1007/s00213-023-06512-6] [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: 08/10/2023] [Accepted: 11/24/2023] [Indexed: 12/05/2023]
Abstract
RATIONALE Preclinical research suggests that pharmacologically elevating cannabinoid levels may attenuate fear memory expression and enhance fear extinction. OBJECTIVES We studied the effects of cannabidiol (CBD) on fear memory expression and fear re-extinction in 69 patients with panic disorder with agoraphobia or with social anxiety disorder. Moderation by sex, diagnosis, and serotonergic antidepressant (AD) use was explored. METHODS A cued fear conditioning paradigm was applied before the first treatment session with 300 mg CBD/placebo augmented exposure therapy. Study medication was administered orally preceding 8 weekly sessions. Fear acquisition and suboptimal extinction took place prior to the first medication ingestion (T0). After the first medication ingestion (T1), we investigated effects on fear memory expression at retention and fear re-extinction. Subjective fear, shock expectancy, skin conductance, and startle responses to conditioned (CS+) and safety stimulus (CS-) were measured. RESULTS Across the sample, CBD reduced shock expectancy at retention under low and ambiguous threat of shock, but fear re-extinction at T1 was unaffected by CBD. However, in AD users, re-extinction of subjective fear was impaired in the CBD condition compared to placebo. In female AD users, CBD interfered with safety learning measured with fear-potentiated startle. CONCLUSIONS The current findings provide no evidence for enhanced fear re-extinction by CBD. However, CBD acutely decreased threat expectation at retention, without affecting other indices of fear. More studies are needed to elucidate possible interactions with AD use and sex, as well as potential effects of CBD on threat expectancies.
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Affiliation(s)
- C M B Kwee
- Department of Experimental Psychology and Helmholtz Institute, Faculty of Social and Behavioral Sciences, Utrecht University, Utrecht, The Netherlands.
- Altrecht Academic Anxiety Center, Utrecht, The Netherlands.
| | - F E van der Flier
- Department of Experimental Psychology and Helmholtz Institute, Faculty of Social and Behavioral Sciences, Utrecht University, Utrecht, The Netherlands
| | - P Duits
- Altrecht Academic Anxiety Center, Utrecht, The Netherlands
| | - A J L M van Balkom
- Department of Psychiatry, Amsterdam Public Health Research Institute, VU University Medical Centre and GGZ inGeest, Amsterdam, the Netherlands
| | - D C Cath
- University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
- Department of Specialist Trainings, GGZ Drenthe, Assen, The Netherlands
| | - J M P Baas
- Department of Experimental Psychology and Helmholtz Institute, Faculty of Social and Behavioral Sciences, Utrecht University, Utrecht, The Netherlands
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Silva HH, Tavares V, Neto BV, Cerqueira F, Medeiros R, Silva MRG. FAAH rs324420 Polymorphism: Biological Pathways, Impact on Elite Athletic Performance and Insights for Sport Medicine. Genes (Basel) 2023; 14:1946. [PMID: 37895295 PMCID: PMC10606937 DOI: 10.3390/genes14101946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 10/11/2023] [Accepted: 10/12/2023] [Indexed: 10/29/2023] Open
Abstract
Gene variation linked to physiological functions is recognised to affect elite athletic performance by modulating training and competition-enabling behaviour. The fatty acid amide hydrolase (FAAH) has been investigated as a good candidate for drug targeting, and recently, its single-nucleotide polymorphism (SNP) rs324420 was reported to be associated with athletic performance. Given the implications, the biological pathways of this genetic polymorphism linked to elite athletic performance, considering sport type, psychological traits and sports injuries, need to be dissected. Thus, a narrative review of the literature concerning the biological mechanisms of this SNP was undertaken. In addition to its role in athletic performance, FAAH rs324420 is also involved in important mechanisms underlying human psychopathologies, including substance abuse and neural dysfunctions. However, cumulative evidence concerning the C385A variant is inconsistent. Therefore, validation studies considering homogeneous sports modalities are required to better define the role of this SNP in elite athletic performance and its impact on stress coping, pain regulation and inflammation control.
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Affiliation(s)
- Hugo-Henrique Silva
- ICBAS-Institute of Biomedical Sciences, University of Porto, 4050-313 Porto, Portugal
- Portuguese Ministry of Education, 1399-025 Lisbon, Portugal
- Leixões Sport Clube, Senior Female Volleyball Team, 4450-277 Matosinhos, Portugal
| | - Valéria Tavares
- ICBAS-Institute of Biomedical Sciences, University of Porto, 4050-313 Porto, Portugal
- Molecular Oncology and Viral Pathology Group, Research Center of IPO Porto (CI-IPOP)/RISE@CI-IPOP, Portuguese Oncology Institute of Porto (IPO Porto)/Porto Comprehensive Cancer Center (Porto.CCC), 4200-072 Porto, Portugal; (B.V.N.); (F.C.)
- FMUP-Faculty of Medicine, University of Porto, 4200-072 Porto, Portugal
| | - Beatriz Vieira Neto
- Molecular Oncology and Viral Pathology Group, Research Center of IPO Porto (CI-IPOP)/RISE@CI-IPOP, Portuguese Oncology Institute of Porto (IPO Porto)/Porto Comprehensive Cancer Center (Porto.CCC), 4200-072 Porto, Portugal; (B.V.N.); (F.C.)
- LPCC, Research Department-Portuguese League Against Cancer (LPPC-NRN), 4200-172 Porto, Portugal
| | - Fátima Cerqueira
- Molecular Oncology and Viral Pathology Group, Research Center of IPO Porto (CI-IPOP)/RISE@CI-IPOP, Portuguese Oncology Institute of Porto (IPO Porto)/Porto Comprehensive Cancer Center (Porto.CCC), 4200-072 Porto, Portugal; (B.V.N.); (F.C.)
- FP-I3ID, FP-BHS, CEBIMED and Faculty of Health Sciences, University Fernando Pessoa, 4200-150 Porto, Portugal;
- CIIMAR/CIMAR, Interdisciplinary Centre of Marine and Environmental Research, 4450-208 Matosinhos, Portugal
| | - Rui Medeiros
- Molecular Oncology and Viral Pathology Group, Research Center of IPO Porto (CI-IPOP)/RISE@CI-IPOP, Portuguese Oncology Institute of Porto (IPO Porto)/Porto Comprehensive Cancer Center (Porto.CCC), 4200-072 Porto, Portugal; (B.V.N.); (F.C.)
- FMUP-Faculty of Medicine, University of Porto, 4200-072 Porto, Portugal
- LPCC, Research Department-Portuguese League Against Cancer (LPPC-NRN), 4200-172 Porto, Portugal
- FP-I3ID, FP-BHS, CEBIMED and Faculty of Health Sciences, University Fernando Pessoa, 4200-150 Porto, Portugal;
- Pathology and Laboratory Medicine Department, Clinical Pathology SVIPO Porto Portuguese Oncology Institute of Porto, 4200-072 Porto, Portugal
| | - Maria-Raquel G. Silva
- FP-I3ID, FP-BHS, CEBIMED and Faculty of Health Sciences, University Fernando Pessoa, 4200-150 Porto, Portugal;
- CIAS-Research Centre for Anthropology and Health-Human Biology, Health and Society, University of Coimbra, 3000-456 Coimbra, Portugal
- CHRC-Comprehensive Health Research Centre, Nova Medical School, Nova University of Lisbon, 1150-090 Lisboa, Portugal
- Scientific Committee of the Gymnastics Federation of Portugal, 1600-159 Lisboa, Portugal
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Ney LJ, Nichols DS, Lipp OV. Fear conditioning depends on the nature of the unconditional stimulus and may be related to hair levels of endocannabinoids. Psychophysiology 2023; 60:e14297. [PMID: 36959707 PMCID: PMC10909444 DOI: 10.1111/psyp.14297] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/01/2023] [Accepted: 03/08/2023] [Indexed: 03/25/2023]
Abstract
The replicability of fear conditioning research has come under recent scrutiny, with increasing acknowledgment that the use of differing materials and methods may lead to incongruent results. Direct comparisons between the main two unconditional stimuli used in fear conditioning - an electric shock or a loud scream-are scarce, and yet these stimuli are usually used interchangeably. In the present study, we tested whether a scream, a shock, or an unpredictable combination of the two affected fear acquisition, extinction, and return of fear amongst healthy participants (N = 109, 81 female). We also collected hair samples and tested the relationship between fear conditioning and hair endocannabinoid levels. Our findings suggest that, although subjective ratings of pleasantness, arousal, and anxiety were similar regardless of the unconditional stimuli used, skin conductance responses were significantly lower for stimuli paired with the scream compared to a shock alone. Further, reducing the predictability of the unconditional stimulus reduced habituation of skin conductance responses during acquisition and reacquisition, but did not produce stronger conditioning compared to shock alone. Exploratory analyses suggested that hair endocannabinoids were associated with overall physiological arousal during fear conditioning, as well as higher return of fear to the threat cue, but not to the safety cue. These findings have multiple implications for the design and replicability of fear conditioning research and provide the first evidence for an association between hair levels of endocannabinoids and human fear conditioning.
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Affiliation(s)
- Luke J. Ney
- School of Psychology and CounsellingQueensland University of TechnologyBrisbaneQueenslandAustralia
| | - David S. Nichols
- Central Science LaboratoryUniversity of TasmaniaHobartTasmaniaAustralia
| | - Ottmar V. Lipp
- School of Psychology and CounsellingQueensland University of TechnologyBrisbaneQueenslandAustralia
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Coelho A, Lima-Bastos S, Gobira P, Lisboa S. Endocannabinoid signaling and epigenetics modifications in the neurobiology of stress-related disorders. Neuronal Signal 2023; 7:NS20220034. [PMID: 37520658 PMCID: PMC10372471 DOI: 10.1042/ns20220034] [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: 01/26/2023] [Revised: 06/30/2023] [Accepted: 07/07/2023] [Indexed: 08/01/2023] Open
Abstract
Stress exposure is associated with psychiatric conditions, such as depression, anxiety, and post-traumatic stress disorder (PTSD). It is also a vulnerability factor to developing or reinstating substance use disorder. Stress causes several changes in the neuro-immune-endocrine axis, potentially resulting in prolonged dysfunction and diseases. Changes in several transmitters, including serotonin, dopamine, glutamate, gamma-aminobutyric acid (GABA), glucocorticoids, and cytokines, are associated with psychiatric disorders or behavioral alterations in preclinical studies. Complex and interacting mechanisms make it very difficult to understand the physiopathology of psychiatry conditions; therefore, studying regulatory mechanisms that impact these alterations is a good approach. In the last decades, the impact of stress on biology through epigenetic markers, which directly impact gene expression, is under intense investigation; these mechanisms are associated with behavioral alterations in animal models after stress or drug exposure, for example. The endocannabinoid (eCB) system modulates stress response, reward circuits, and other physiological functions, including hypothalamus-pituitary-adrenal axis activation and immune response. eCBs, for example, act retrogradely at presynaptic neurons, limiting the release of neurotransmitters, a mechanism implicated in the antidepressant and anxiolytic effects after stress. Epigenetic mechanisms can impact the expression of eCB system molecules, which in turn can regulate epigenetic mechanisms. This review will present evidence of how the eCB system and epigenetic mechanisms interact and the consequences of this interaction in modulating behavioral changes after stress exposure in preclinical studies or psychiatric conditions. Moreover, evidence that correlates the involvement of the eCB system and epigenetic mechanisms in drug abuse contexts will be discussed.
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Affiliation(s)
- Arthur A. Coelho
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, Brazil
- Department of BioMolecular Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Brazil
| | - Sávio Lima-Bastos
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, Brazil
- Department of BioMolecular Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Brazil
| | - Pedro H. Gobira
- Department of BioMolecular Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Brazil
| | - Sabrina F. Lisboa
- Department of BioMolecular Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Brazil
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Ney LJ, Akosile W, Davey C, Pitcher L, Felmingham KL, Mayo LM, Hill MN, Strodl E. Challenges and considerations for treating PTSD with medicinal cannabis: the Australian clinician's perspective. Expert Rev Clin Pharmacol 2023; 16:1093-1108. [PMID: 37885234 DOI: 10.1080/17512433.2023.2276309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 10/24/2023] [Indexed: 10/28/2023]
Abstract
INTRODUCTION Preclinical and experimental research have provided promising evidence that medicinal cannabis may be efficacious in the treatment of posttraumatic stress disorder (PTSD). However, implementation of medicinal cannabis into routine clinical therapies may not be straightforward. AREAS COVERED In this review, we describe some of the clinical, practical, and safety challenges that must be addressed for cannabis-based treatment of PTSD to be feasible in a real-world setting. These issues are especially prevalent if medicinal cannabis is to be combined with trauma-focused psychotherapy. EXPERT OPINION Future consideration of the clinical and practical considerations of cannabis use in PTSD therapy will be essential to both the efficacy and safety of the treatment protocols that are being developed. These issues include dose timing and titration, potential for addiction, product formulation, windows of intervention, and route of administration. In particular, exposure therapy for PTSD involves recall of intense emotions, and the interaction between cannabis use and reliving of trauma memories must be explored in terms of patient safety and impact on therapeutic outcomes.
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Affiliation(s)
- Luke J Ney
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Wole Akosile
- Greater Brisbane Clinical School, Faculty of Medicine, University of Queensland, Brisbane, Australia
| | - Chris Davey
- Department of Psychiatry, Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Australia
| | | | - Kim L Felmingham
- School of Psychological Sciences, Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Australia
| | - Leah M Mayo
- Department of Psychiatry, Mathison Centre for Mental Health Research, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Matthew N Hill
- Department of Psychiatry, Mathison Centre for Mental Health Research, and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Esben Strodl
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Brisbane, Australia
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Ney LJ, Cooper J, Lam GN, Moffitt K, Nichols DS, Mayo LM, Lipp OV. Hair endocannabinoids predict physiological fear conditioning and salivary endocannabinoids predict subjective stress reactivity in humans. Psychoneuroendocrinology 2023; 154:106296. [PMID: 37216738 DOI: 10.1016/j.psyneuen.2023.106296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 05/17/2023] [Accepted: 05/17/2023] [Indexed: 05/24/2023]
Abstract
On the basis of substantial preclinical evidence, the endogenous cannabinoid system has been proposed to be closely involved in stress reactivity and extinction of fear. Existing human research supports this proposal to some extent, but existing studies have used only a narrow range of tools and biomatrices to measure endocannabinoids during stress and fear experiments. In the present study we collected hair and saliva samples from 99 healthy participants who completed a fear conditioning and intrusive memory task. Subjective, physiological and biological stress reactivity to a trauma film, which later served as unconditional stimulus during fear conditioning, was also measured. We found that salivary endocannabinoid concentrations predicted subjective responses to stress, but not cortisol stress reactivity, and replicated previous findings demonstrating a sex dimorphism in hair and salivary endocannabinoid levels. Hair 2-arachidonoyl glycerol levels were significantly associated with better retention of safety learning during extinction and renewal phases of fear conditioning, while hair concentrations of oleoylethanolamide and palmitoylethanolamide were associated with overall physiological arousal, but not conditional learning, during fear conditioning. This study is the first to test the relationship between hair and salivary endocannabinoids and these important psychological processes. Our results suggest that these measures may serve as biomarkers of dysregulation in human fear memory and stress.
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Affiliation(s)
- Luke J Ney
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Brisbane, Australia.
| | - Jack Cooper
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Gia Nhi Lam
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Kaylee Moffitt
- Faculty of Science, Queensland University of Technology, Brisbane, Australia
| | - David S Nichols
- Central Science Laboratory, University of Tasmania, Hobart, Australia
| | - Leah M Mayo
- Department of Psychiatry, Mathison Centre for Mental Health Research, and Hotchkiss Brain Institute, University of Calgary, Canada
| | - Ottmar V Lipp
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Brisbane, Australia
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Battaglia S, Di Fazio C, Vicario CM, Avenanti A. Neuropharmacological Modulation of N-methyl-D-aspartate, Noradrenaline and Endocannabinoid Receptors in Fear Extinction Learning: Synaptic Transmission and Plasticity. Int J Mol Sci 2023; 24:ijms24065926. [PMID: 36983000 PMCID: PMC10053024 DOI: 10.3390/ijms24065926] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 03/10/2023] [Accepted: 03/13/2023] [Indexed: 03/30/2023] Open
Abstract
Learning to recognize and respond to potential threats is crucial for survival. Pavlovian threat conditioning represents a key paradigm for investigating the neurobiological mechanisms of fear learning. In this review, we address the role of specific neuropharmacological adjuvants that act on neurochemical synaptic transmission, as well as on brain plasticity processes implicated in fear memory. We focus on novel neuropharmacological manipulations targeting glutamatergic, noradrenergic, and endocannabinoid systems, and address how the modulation of these neurobiological systems affects fear extinction learning in humans. We show that the administration of N-methyl-D-aspartate (NMDA) agonists and modulation of the endocannabinoid system by fatty acid amide hydrolase (FAAH) inhibition can boost extinction learning through the stabilization and regulation of the receptor concentration. On the other hand, elevated noradrenaline levels dynamically modulate fear learning, hindering long-term extinction processes. These pharmacological interventions could provide novel targeted treatments and prevention strategies for fear-based and anxiety-related disorders.
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Affiliation(s)
- Simone Battaglia
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology "Renzo Canestrari", Cesena Campus, Alma Mater Studiorum Università di Bologna, 47521 Cesena, Italy
- Department of Psychology, University of Turin, 10124 Turin, Italy
| | - Chiara Di Fazio
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology "Renzo Canestrari", Cesena Campus, Alma Mater Studiorum Università di Bologna, 47521 Cesena, Italy
| | - Carmelo M Vicario
- Dipartimento di Scienze Cognitive, Psicologiche, Pedagogiche e Degli Studi Culturali, Università Degli Studi di Messina, 98122 Messina, Italy
| | - Alessio Avenanti
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology "Renzo Canestrari", Cesena Campus, Alma Mater Studiorum Università di Bologna, 47521 Cesena, Italy
- Neuropsicology and Cognitive Neuroscience Research Center (CINPSI Neurocog), Universidad Católica del Maule, Talca 3460000, Chile
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Dargahi M, Karimi G, Etemad L, Alavi MS, Roohbakhsh A. Fatty acid amide hydrolase inhibitor URB597 suppressed conditioned and sensitized fear responses in a rat model of post-traumatic stress disorder. LEARNING AND MOTIVATION 2023. [DOI: 10.1016/j.lmot.2023.101872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Schenker MT, Ince S, Ney LJ, Hsu CMK, Zuj DV, Jordan AS, Nicholas CL, Felmingham KL. Sex differences in the effect of subjective sleep on fear conditioning, extinction learning, and extinction recall in individuals with a range of PTSD symptom severity. Behav Res Ther 2022; 159:104222. [PMID: 36327524 DOI: 10.1016/j.brat.2022.104222] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 10/17/2022] [Accepted: 10/21/2022] [Indexed: 12/14/2022]
Abstract
Sleep has been found to play a key role in fear conditioning, extinction learning and extinction recall, and sleep disturbances are linked to many mental disorders including post-traumatic stress disorder (PTSD). Previous studies examining associations between sleep and fear or extinction processes primarily focused on objectively measured sleep architecture. Little research has so far focused on subjective sleep measures and particularly in clinical populations, which often experience subjectively poor sleep, including PTSD. Here we investigated whether subjective sleep disturbance, sleep onset latency, wake after sleep onset or sleep efficiency were related to fear conditioning, extinction learning or extinction recall in a large sample of individuals with a range of PTSD symptom severity (n = 248). Overall, we did not find that subjective sleep was associated with fear conditioning or extinction processes. However, exploratory analyses examining the moderating effect of sex found that shorter sleep onset latency and greater sleep efficiency were associated with improved extinction recall in women with higher PTSD symptom severity. This suggests that less time falling asleep and longer time asleep while in bed may be protective in highly symptomatic women against the commonly observed impaired extinction recall in PTSD. More studies are needed to explore sex-specific effects further.
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Affiliation(s)
- Maya T Schenker
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, VIC, Australia.
| | - Sevil Ince
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, VIC, Australia.
| | - Luke J Ney
- School of Psychological Sciences, University of Tasmania, Hobart, TAS, Australia; School of Psychology and Counselling, Queensland University of Technology, Brisbane, QLD, Australia.
| | - Chia-Ming K Hsu
- School of Psychological Sciences, University of Tasmania, Hobart, TAS, Australia.
| | - Daniel V Zuj
- School of Psychological Sciences, University of Tasmania, Hobart, TAS, Australia.
| | - Amy S Jordan
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, VIC, Australia.
| | - Christian L Nicholas
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, VIC, Australia.
| | - Kim L Felmingham
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, VIC, Australia; School of Psychological Sciences, University of Tasmania, Hobart, TAS, Australia.
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12
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Laing PAF, Felmingham KL, Davey CG, Harrison BJ. The neurobiology of Pavlovian safety learning: Towards an acquisition-expression framework. Neurosci Biobehav Rev 2022; 142:104882. [PMID: 36150453 DOI: 10.1016/j.neubiorev.2022.104882] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 09/15/2022] [Accepted: 09/16/2022] [Indexed: 11/19/2022]
Abstract
Safety learning creates associations between conditional stimuli and the absence of threat. Studies of human fear conditioning have accumulated evidence for the neural signatures of safety over various paradigms, aligning on several common brain systems. While these systems are often interpreted as underlying safety learning in a generic sense, they may instead reflect the expression of learned safety, pertaining to processes of fear inhibition, positive affect, and memory. Animal models strongly suggest these can be separable from neural circuits implicated in the conditioning process itself (or safety acquisition). While acquisition-expression distinctions are ubiquitous in behavioural science, this lens has not been applied to safety learning, which remains a novel area in the field. In this mini-review, we overview findings from prevalent safety paradigms in humans, and synthesise these with insights from animal models to propose that the neurobiology of safety learning be conceptualised along an acquisition-expression model, with the aim of stimulating richer brain-based characterisations of this important process.
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Affiliation(s)
- Patrick A F Laing
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Australia.
| | - Kim L Felmingham
- Melbourne School of Psychological Sciences, The University of Melbourne, Australia
| | - Christopher G Davey
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Australia
| | - Ben J Harrison
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Australia.
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13
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Haviv Y, Georgiev O, Gaver-Bracha T, Hamad S, Nemirovski A, Hadar R, Sharav Y, Aframian DJ, Brotman Y, Tam J. Reduced Endocannabinoid Tone in Saliva of Chronic Orofacial Pain Patients. Molecules 2022; 27:molecules27144662. [PMID: 35889535 PMCID: PMC9322033 DOI: 10.3390/molecules27144662] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 07/14/2022] [Accepted: 07/19/2022] [Indexed: 02/01/2023] Open
Abstract
Background: the endocannabinoid system (ECS) participates in many physiological and pathological processes including pain generation, modulation, and sensation. Its involvement in chronic orofacial pain (OFP) in general, and the reflection of its involvement in OFP in salivary endocannabinoid (eCBs) levels in particular, has not been examined. Objectives: to evaluate the association between salivary (eCBs) levels and chronic OFP. Methods: salivary levels of 2 eCBs, anandamide (AEA), 2-arachidonoylglycerol (2-AG), 2 endocannabinoid-like compoundsN-palmitoylethanolamine (PEA), N-oleoylethanolamine (OEA), and their endogenous precursor and breakdown product, arachidonic acid (AA), were analyzed using liquid chromatography/tandem mass spectrometry in 83 chronic OFP patients and 43 pain-free controls. The chronic OFP patients were divided according to diagnosis into musculoskeletal, neurovascular/migraine, and neuropathic pain types. Results: chronic OFP patients had lower levels of OEA (p = 0.02) and 2-AG (p = 0.01). Analyzing specific pain types revealed lower levels of AEA and OEA in the neurovascular group (p = 0.04, 0.02, respectively), and 2-AG in the neuropathic group compared to controls (p = 0.05). No significant differences were found between the musculoskeletal pain group and controls. Higher pain intensity was accompanied by lower levels of AA (p = 0.028), in neuropathic group. Conclusions: lower levels of eCBs were found in the saliva of chronic OFP patients compared to controls, specifically those with neurovascular/migraine, and neuropathic pain. The detection of changes in salivary endocannabinoids levels related to OFP adds a new dimension to our understanding of OFP mechanisms, and may have diagnostic as well as therapeutic implications for pain.
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Affiliation(s)
- Yaron Haviv
- Department of Oral Medicine, Sedation and Maxillofacial Imaging, Hebrew University-Hadassah School of Dental Medicine, Jerusalem 91120, Israel; (O.G.); (T.G.-B.); (Y.S.); (D.J.A.); (J.T.)
- Correspondence: ; Tel.: +972-2-677-6140; Fax: +972-2-644-7919
| | - Olga Georgiev
- Department of Oral Medicine, Sedation and Maxillofacial Imaging, Hebrew University-Hadassah School of Dental Medicine, Jerusalem 91120, Israel; (O.G.); (T.G.-B.); (Y.S.); (D.J.A.); (J.T.)
- In Partial Fulfillment of DMD Requirements, Hebrew University-Hadassah School of Dental Medicine, Jerusalem 91120, Israel
| | - Tal Gaver-Bracha
- Department of Oral Medicine, Sedation and Maxillofacial Imaging, Hebrew University-Hadassah School of Dental Medicine, Jerusalem 91120, Israel; (O.G.); (T.G.-B.); (Y.S.); (D.J.A.); (J.T.)
- In Partial Fulfillment of DMD Requirements, Hebrew University-Hadassah School of Dental Medicine, Jerusalem 91120, Israel
| | - Sharleen Hamad
- Obesity and Metabolism Laboratory, The Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112001, Israel; (S.H.); (A.N.); (R.H.)
| | - Alina Nemirovski
- Obesity and Metabolism Laboratory, The Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112001, Israel; (S.H.); (A.N.); (R.H.)
| | - Rivka Hadar
- Obesity and Metabolism Laboratory, The Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112001, Israel; (S.H.); (A.N.); (R.H.)
| | - Yair Sharav
- Department of Oral Medicine, Sedation and Maxillofacial Imaging, Hebrew University-Hadassah School of Dental Medicine, Jerusalem 91120, Israel; (O.G.); (T.G.-B.); (Y.S.); (D.J.A.); (J.T.)
| | - Doron J. Aframian
- Department of Oral Medicine, Sedation and Maxillofacial Imaging, Hebrew University-Hadassah School of Dental Medicine, Jerusalem 91120, Israel; (O.G.); (T.G.-B.); (Y.S.); (D.J.A.); (J.T.)
| | - Yariv Brotman
- Department of Life Sciences, Ben-Gurion University of the Negev, Beersheba 8410501, Israel;
| | - Joseph Tam
- Department of Oral Medicine, Sedation and Maxillofacial Imaging, Hebrew University-Hadassah School of Dental Medicine, Jerusalem 91120, Israel; (O.G.); (T.G.-B.); (Y.S.); (D.J.A.); (J.T.)
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14
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Combining the trauma film and fear conditioning paradigms: A theoretical review and meta-analysis with relevance to PTSD. Behav Res Ther 2022; 152:104081. [DOI: 10.1016/j.brat.2022.104081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 03/09/2022] [Accepted: 03/15/2022] [Indexed: 01/01/2023]
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15
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Molecular Alterations of the Endocannabinoid System in Psychiatric Disorders. Int J Mol Sci 2022; 23:ijms23094764. [PMID: 35563156 PMCID: PMC9104141 DOI: 10.3390/ijms23094764] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/22/2022] [Accepted: 04/23/2022] [Indexed: 02/07/2023] Open
Abstract
The therapeutic benefits of the current medications for patients with psychiatric disorders contrast with a great variety of adverse effects. The endocannabinoid system (ECS) components have gained high interest as potential new targets for treating psychiatry diseases because of their neuromodulator role, which is essential to understanding the regulation of many brain functions. This article reviewed the molecular alterations in ECS occurring in different psychiatric conditions. The methods used to identify alterations in the ECS were also described. We used a translational approach. The animal models reproducing some behavioral and/or neurochemical aspects of psychiatric disorders and the molecular alterations in clinical studies in post-mortem brain tissue or peripheral tissues were analyzed. This article reviewed the most relevant ECS changes in prevalent psychiatric diseases such as mood disorders, schizophrenia, autism, attentional deficit, eating disorders (ED), and addiction. The review concludes that clinical research studies are urgently needed for two different purposes: (1) To identify alterations of the ECS components potentially useful as new biomarkers relating to a specific disease or condition, and (2) to design new therapeutic targets based on the specific alterations found to improve the pharmacological treatment in psychiatry.
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16
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Genetic influences on central and peripheral nervous system activity during fear conditioning. Transl Psychiatry 2022; 12:95. [PMID: 35260551 PMCID: PMC8904491 DOI: 10.1038/s41398-022-01861-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 11/25/2022] Open
Abstract
Fear conditioning is an evolutionarily conserved type of learning serving as a model for the acquisition of situationally induced anxiety. Brain function supporting fear conditioning may be genetically influenced, which in part could explain genetic susceptibility for anxiety following stress exposure. Using a classical twin design and functional magnetic resonance imaging, we evaluated genetic influences (h2) on brain activity and standard autonomic measures during fear conditioning. We found an additive genetic influence on mean brain activation (h2 = 0.34) and autonomic responses (h2 = 0.24) during fear learning. The experiment also allowed estimation of the genetic influence on brain activation during safety learning (h2 = 0.55). The mean safety, but not fear, related brain activation was genetically correlated with autonomic responses. We conclude that fear and safety learning processes, both involved in anxiety development, are moderately genetically influenced as expressed both in the brain and the body.
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17
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Crombie KM, Privratsky AA, Schomaker CM, Heilicher M, Ross MC, Sartin-Tarm A, Sellnow K, Binder EB, Andrew James G, Cisler JM. The influence of FAAH genetic variation on physiological, cognitive, and neural signatures of fear acquisition and extinction learning in women with PTSD. Neuroimage Clin 2022; 33:102922. [PMID: 34952353 PMCID: PMC8715233 DOI: 10.1016/j.nicl.2021.102922] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 12/16/2021] [Accepted: 12/18/2021] [Indexed: 12/14/2022]
Abstract
PTSD is often treated with psychotherapies based on principles of fear acquisition and extinction. Increased AEA has resulted in enhanced extinction learning and recall among healthy adults. These effects have not yet been comprehensively examined in a PTSD population. Results suggest that genetic variation within the FAAH gene affects how fear learning is tuned in women with PTSD.
Background Posttraumatic Stress Disorder (PTSD) is commonly treated with exposure-based cognitive therapies that are based on the principles of fear acquisition and extinction learning. Elevations in one of the major endocannabinoids (anandamide) either via inhibition of the primary degrading enzyme (fatty acid amide hydrolase; FAAH) or via a genetic variation in the FAAH gene (C385A; rs324420) has resulted in accelerated extinction learning and enhanced extinction recall among healthy adults. These results suggest that targeting FAAH may be a promising therapeutic approach for PTSD. However, these effects have not yet been comprehensively examined in a PTSD population. Methods The current study examined whether genetic variation in the FAAH gene (CC [n = 49] vs AA/AC [n = 36] allele carriers) influences physiological (skin conductance), cognitive (threat expectancy), and neural (network and voxel-wise activation) indices of fear acquisition and extinction learning among a sample of adult women with PTSD (N = 85). Results The physiological, cognitive, and neural signatures of fear acquisition and extinction learning varied as a function of whether or not individuals possess the FAAH C385A polymorphism. For instance, we report divergent responding between CC and AA/AC allele carriers to CS + vs CS- in limbic and striatum networks and overall greater activation throughout the task among AA/AC allele carriers in several regions [e.g., inferior frontal, middle frontal, parietal] that are highly consistent with a frontoparietal network involved in higher-order executive functions. Conclusions These results suggest that genetic variation within the FAAH gene influences physiological, cognitive, and neural signatures of fear learning in women with PTSD. In order to advance our understanding of the efficacy of FAAH inhibition as a treatment for PTSD, future clinical trials in this area should assess genetic variation in the FAAH gene in order to fully depict and differentiate the acute effects of a drug manipulation (FAAH inhibition) from more chronic (genetic) influences on fear extinction processes.
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Affiliation(s)
- Kevin M Crombie
- The University of Texas at Austin, Department of Psychiatry and Behavioral Sciences, Health Discovery Building, 1601 Trinity St., Building B, Austin, TX 78712, USA.
| | - Anthony A Privratsky
- University of Arkansas for Medical Sciences, Brain Imaging Research Center, 4301 W. Markham Street #554, Little Rock, AR 72205, USA
| | - Chloe M Schomaker
- The University of Texas at Austin, Department of Psychiatry and Behavioral Sciences, Health Discovery Building, 1601 Trinity St., Building B, Austin, TX 78712, USA
| | - Mickela Heilicher
- University of Wisconsin - Madison, Department of Psychiatry, 6001 Research Park Boulevard, Madison, WI 53719-1176608-262-6375, USA
| | - Marisa C Ross
- University of Wisconsin - Madison, Department of Psychiatry, 6001 Research Park Boulevard, Madison, WI 53719-1176608-262-6375, USA
| | - Anneliis Sartin-Tarm
- University of Wisconsin - Madison, Department of Psychiatry, 6001 Research Park Boulevard, Madison, WI 53719-1176608-262-6375, USA
| | - Kyrie Sellnow
- University of Wisconsin - Madison, Department of Psychiatry, 6001 Research Park Boulevard, Madison, WI 53719-1176608-262-6375, USA
| | - Elisabeth B Binder
- Max Planck Institute of Psychiatry, Department of Translational Psychiatry, Kraepelinstr. 2-10, 80804, Munchen, Germany; Emory University, Department of Psychiatry and Behavioral Sciences, 12 Executive Park Dr NE #200, Atlanta, GA 30329, USA
| | - G Andrew James
- University of Arkansas for Medical Sciences, Brain Imaging Research Center, 4301 W. Markham Street #554, Little Rock, AR 72205, USA
| | - Josh M Cisler
- The University of Texas at Austin, Department of Psychiatry and Behavioral Sciences, Health Discovery Building, 1601 Trinity St., Building B, Austin, TX 78712, USA
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18
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Mayo LM, Rabinak CA, Hill MN, Heilig M. Targeting the Endocannabinoid System in the Treatment of Posttraumatic Stress Disorder: A Promising Case of Preclinical-Clinical Translation? Biol Psychiatry 2022; 91:262-272. [PMID: 34598785 PMCID: PMC11097652 DOI: 10.1016/j.biopsych.2021.07.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 07/01/2021] [Accepted: 07/19/2021] [Indexed: 01/03/2023]
Abstract
The endocannabinoid (eCB) system is one the most ubiquitous signaling systems of the brain and offers a rich pharmacology including multiple druggable targets. Preclinical research shows that eCB activity influences functional connectivity between the prefrontal cortex and amygdala and thereby influences an organism's ability to cope with threats and stressful experiences. Animal studies show that CB1 receptor activation within the amygdala is essential for extinction of fear memories. Failure to extinguish traumatic memories is a core symptom of posttraumatic stress disorder, suggesting that potentiating eCB signaling may have a therapeutic potential in this condition. However, it has been unknown whether animal findings in this domain translate to humans. Data to inform this critical question are now emerging and are the focus of this review. We first briefly summarize the biology of the eCB system and the animal studies that support its role in fear extinction and stress responding. We then discuss the pharmacological eCB-targeting strategies that may be exploited for therapeutic purposes: direct CB1 receptor activation, using Δ9-tetrahydrocannabinol or its synthetic analogs; or indirect potentiation, through inhibition of eCB-degrading enzymes, the anandamide-degrading enzyme fatty acid amide hydrolase; or the 2-AG (2-arachidonoyl glycerol)-degrading enzyme monoacylglycerol lipase. We then review recent human data on direct CB1 receptor activation via Δ9-tetrahydrocannabinol and anandamide potentiation through fatty acid amide hydrolase blockade. The available human data consistently support a translation of animal findings on fear memories and stress reactivity and suggest a potential therapeutic utility in humans.
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Affiliation(s)
- Leah M Mayo
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Science, Linköping University, Linköping, Sweden.
| | - Christine A Rabinak
- Department of Pharmacy Practice, Translational Neuroscience Program, Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, Michigan
| | - Matthew N Hill
- Departments of Cell Biology and Anatomy & Psychiatry, Hotchkiss Brain Institute and the Mathison Centre for Mental Health Research and Education, University of Calgary, Calgary, Alberta, Canada
| | - Markus Heilig
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Science, Linköping University, Linköping, Sweden
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Ney LJ, Crombie KM, Mayo LM, Felmingham KL, Bowser T, Matthews A. Translation of animal endocannabinoid models of PTSD mechanisms to humans: Where to next? Neurosci Biobehav Rev 2021; 132:76-91. [PMID: 34838529 DOI: 10.1016/j.neubiorev.2021.11.040] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 11/21/2021] [Accepted: 11/22/2021] [Indexed: 12/11/2022]
Abstract
The endocannabinoid system is known to be involved in mechanisms relevant to PTSD aetiology and maintenance, though this understanding is mostly based on animal models of the disorder. Here we review how human paradigms can successfully translate animal findings to human subjects, with the view that substantially increased insight into the effect of endocannabinoid signalling on stress responding, emotional and intrusive memories, and fear extinction can be gained using modern paradigms and methods for assessing the state of the endocannabinoid system in PTSD.
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Affiliation(s)
- Luke J Ney
- School of Psychological Sciences, University of Tasmania, Australia; School of Psychology and Counselling, Queensland University of Technology, Australia.
| | - Kevin M Crombie
- Department of Psychiatry and Behavioral Sciences, University of Texas at Austin, United States
| | - Leah M Mayo
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Science, Linköping University, Sweden
| | - Kim L Felmingham
- Department of Psychological Sciences, University of Melbourne, Australia
| | | | - Allison Matthews
- School of Psychological Sciences, University of Tasmania, Australia
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