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Avgana H, Toledano RS, Akirav I. Examining the Role of Oxytocinergic Signaling and Neuroinflammatory Markers in the Therapeutic Effects of MDMA in a Rat Model for PTSD. Pharmaceuticals (Basel) 2024; 17:846. [PMID: 39065697 PMCID: PMC11279644 DOI: 10.3390/ph17070846] [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] [Received: 05/27/2024] [Revised: 06/20/2024] [Accepted: 06/25/2024] [Indexed: 07/28/2024] Open
Abstract
MDMA-assisted psychotherapy has shown potential as an effective treatment for post-traumatic stress disorder (PTSD). Preclinical studies involving rodents have demonstrated that MDMA can facilitate the extinction of fear memories. It has been noted that MDMA impacts oxytocin neurons and pro-inflammatory cytokines. Thus, the aim of this study was to explore the role of oxytocinergic signaling and neuroinflammatory markers in the therapeutic effects of MDMA. To achieve this, male rats were subjected to a model of PTSD involving exposure to shock and situational reminders. MDMA was microinjected into the medial prefrontal cortex (mPFC) before extinction training, followed by behavioral tests assessing activity levels, anxiety, and social function. Our findings indicate that MDMA treatment facilitated fear extinction and mitigated the shock-induced increase in freezing, as well as deficits in social behavior. Shock exposure led to altered expression of the gene coding for OXT-R and neuroinflammation in the mPFC and basolateral amygdala (BLA), which were restored by MDMA treatment. Importantly, the OXT-R antagonist L-368,899 prevented MDMA's therapeutic effects on extinction and freezing behavior. In conclusion, MDMA's therapeutic effects in the PTSD model are associated with alterations in OXT-R expression and neuroinflammation, and MDMA's effects on extinction and anxiety may be mediated by oxytocinergic signaling.
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Affiliation(s)
- Haron Avgana
- Department of Psychology, School of Psychological Sciences, University of Haifa, Haifa 3498838, Israel; (H.A.); (R.S.T.)
- The Integrated Brain and Behavior Research Center (IBBRC), University of Haifa, Haifa 3498838, Israel
| | - Roni Shira Toledano
- Department of Psychology, School of Psychological Sciences, University of Haifa, Haifa 3498838, Israel; (H.A.); (R.S.T.)
- The Integrated Brain and Behavior Research Center (IBBRC), University of Haifa, Haifa 3498838, Israel
| | - Irit Akirav
- Department of Psychology, School of Psychological Sciences, University of Haifa, Haifa 3498838, Israel; (H.A.); (R.S.T.)
- The Integrated Brain and Behavior Research Center (IBBRC), University of Haifa, Haifa 3498838, Israel
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Li S, He Y, Turner D, Wei N, Ma L, Taylor DH, Taylor DT, Ji X, Wu J. Electrophysiological Phenotypes of Hippocampal Synaptic and Network Functions in Cannabinoid Receptor 2 Knockout Mice. Cannabis Cannabinoid Res 2024. [PMID: 38502778 DOI: 10.1089/can.2023.0186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024] Open
Abstract
Background: The cannabinoid receptor 2 (CB2R), a cannabinoid receptor primarily expressed in immune cells, has been found in the brain, particularly in the hippocampus, where it plays crucial roles in modulating various neural functions, including synaptic plasticity, neuroprotection, neurogenesis, anxiety and stress responses, and neuroinflammation. Despite this growing understanding, the intricate electrophysiological characteristics of hippocampal neurons in CB2R knockout (CB2R KO) mice remain elusive. Aim and Methods: This study aimed to comprehensively assess the electrophysiological traits of hippocampal synaptic and network functions in CB2R KO mice. The focus was on aspects such as synaptic transmission, short- and long-term synaptic plasticity, and neural network synchrony (theta oscillations). Results: Our findings unveiled multiple functional traits in these CB2R KO mice, notably elevated synaptic transmission in hippocampal CA1 neurons, decreased both synaptic short-term plasticity (paired-pulse facilitation) and long-term potentiation (LTP), and impaired neural network synchronization. Conclusion: In essence, this study yields insightful revelations about the influence of CB2Rs on hippocampal neural functions. By illuminating the electrophysiological modifications in CB2R KO mice, our research enriches the comprehension of CB2R involvement in hippocampal function. Such insights could hold implications for advancing our understanding of the neural mechanisms under the influence of CB2Rs within the brain.
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Affiliation(s)
- Shuangtao Li
- Brain Function and Disease Laboratory, Shantou University Medical College, Shantou, Guangdong, China
| | - Yongchang He
- Department of Neurobiology, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Dharshaun Turner
- Department of Neurobiology, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Naili Wei
- Department of Neurosurgery, First Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong, China
| | - Luyao Ma
- Department of Neurobiology, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Devin H Taylor
- Department of Neurobiology, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
- Department of Biology, Utah Valley University, Orem, Utah, USA
| | | | - Xiaoyu Ji
- Brain Function and Disease Laboratory, Shantou University Medical College, Shantou, Guangdong, China
- Department of Neurosurgery, First Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong, China
| | - Jie Wu
- Brain Function and Disease Laboratory, Shantou University Medical College, Shantou, Guangdong, China
- Department of Neurobiology, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
- Department of Neurosurgery, First Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong, China
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Oddi S, Fiorenza MT, Maccarrone M. Endocannabinoid signaling in adult hippocampal neurogenesis: A mechanistic and integrated perspective. Prog Lipid Res 2023; 91:101239. [PMID: 37385352 DOI: 10.1016/j.plipres.2023.101239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 06/01/2023] [Accepted: 06/25/2023] [Indexed: 07/01/2023]
Abstract
Dentate gyrus of the hippocampus continuously gives rise to new neurons, namely, adult-born granule cells, which contribute to conferring plasticity to the mature brain throughout life. Within this neurogenic region, the fate and behavior of neural stem cells (NSCs) and their progeny result from a complex balance and integration of a variety of cell-autonomous and cell-to-cell-interaction signals and underlying pathways. Among these structurally and functionally diverse signals, there are endocannabinoids (eCBs), the main brain retrograde messengers. These pleiotropic bioactive lipids can directly and/or indirectly influence adult hippocampal neurogenesis (AHN) by modulating, both positively and negatively, multiple molecular and cellular processes in the hippocampal niche, depending on the cell type or stage of differentiation. Firstly, eCBs act directly as cell-intrinsic factors, cell-autonomously produced by NSCs following their stimulation. Secondly, in many, if not all, niche-associated cells, including some local neuronal and nonneuronal elements, the eCB system indirectly modulates the neurogenesis, linking neuronal and glial activity to regulating distinct stages of AHN. Herein, we discuss the crosstalk of the eCB system with other neurogenesis-relevant signal pathways and speculate how the hippocampus-dependent neurobehavioral effects elicited by (endo)cannabinergic medications are interpretable in light of the key regulatory role that eCBs play on AHN.
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Affiliation(s)
- Sergio Oddi
- Department of Veterinary Medicine, University of Teramo, Via R. Balzarini 1, 64100 Teramo, Italy; European Center for Brain Research/IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143 Rome, Italy.
| | - Maria Teresa Fiorenza
- European Center for Brain Research/IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143 Rome, Italy; Department of Psychology, Division of Neuroscience and "Daniel Bovet" Neurobiology Research Center, Sapienza University of Rome, Via dei Sardi 70, 00185 Rome, Italy
| | - Mauro Maccarrone
- European Center for Brain Research/IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143 Rome, Italy; Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Via Vetoio Snc, 67100 L'Aquila, Italy
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4
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The infralimbic mineralocorticoid blockage prevents the stress-induced impairment of aversive memory extinction in rats. Transl Psychiatry 2022; 12:343. [PMID: 35999226 PMCID: PMC9399104 DOI: 10.1038/s41398-022-02118-2] [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: 02/07/2022] [Revised: 08/09/2022] [Accepted: 08/11/2022] [Indexed: 11/09/2022] Open
Abstract
Individuals deal with adversity and return to a normal lifestyle when adversity ends. Nevertheless, in specific cases, traumas may be preceded by memory distortions in stress-related malaises, and memory extinction impairment is strictly associated with the symptoms of post-traumatic stress disorder. Glucocorticoids (GCs), the central stress mediator, target mineralocorticoid (MR) and glucocorticoid (GR) receptors and coordinate stress responses. Despite MRs being present in brain regions essential to cognition, emotions, and initial stress processing, such as the medial prefrontal cortex (mPFC), most studies attempt to elucidate the stress-induced deleterious actions of GCs via GR. Therefore, it is necessary to understand the relationship between stress, infralimbic mPFC (IL), and memory and how MR-mediated intracellular signaling influences this relationship and modulates memory extinction. We observed that acutely restraint-stressed male Wistar rats showed high corticosterone (CORT) levels, and previous intra-IL-spironolactone administration (a selective MR antagonist) decreased it 60 min after the stress started. Intra-IL-CORT118335, a novel mixed MR/GR selective modulator, increased CORT throughout stress exposure. Ten days after stress, all rats increased freezing in the memory retrieval test and acquired the aversive contextual memory. During the extinction test, intra-IL injection of spironolactone, but not CORT118335, prevented the stress-impaired memory extinction, suggesting that the IL-MR activity controls CORT concentration, and it is crucial to the establishment of late extinction impairment. Also, the concomitant GR full activation overrode MR blockage. It increased CORT levels leading to the stress-induced extinction memory impairment, reinforcing that the MR/GR balance is crucial to predicting stress-induced behavioral outcomes.
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Enhancing Endocannabinoid Signaling via β-Catenin in the Nucleus Accumbens Attenuates PTSD- and Depression-like Behavior of Male Rats. Biomedicines 2022; 10:biomedicines10081789. [PMID: 35892688 PMCID: PMC9394396 DOI: 10.3390/biomedicines10081789] [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] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 07/14/2022] [Accepted: 07/20/2022] [Indexed: 12/15/2022] Open
Abstract
Inhibition of fatty acid amide hydrolase (FAAH), which increases anandamide levels, has been suggested as a potential treatment for stress-related conditions. We examined whether the stress-preventing effects of the FAAH inhibitor URB597 on behavior are mediated via β-catenin in the nucleus accumbens (NAc). Male rats were exposed to the shock and reminders model of PTSD and then treated with URB597 (0.4 mg/kg; i.p.). They were tested for anxiety- (freezing, startle response), depression-like behaviors (despair, social preference, anhedonia), and memory function (T-maze, social recognition). We also tested the involvement of the CB1 receptor (CB1r), β-catenin, and metabotropic glutamate receptor subtype 5 (mGluR5) proteins. URB597 prevented the shock- and reminders-induced increase in anxiety- and depressive-like behaviors, as well as the impaired memory via the CB1r-dependent mechanism. In the NAc, viral-mediated β-catenin overexpression restored the behavior of rats exposed to stress and normalized the alterations in protein levels in the NAc and the prefrontal cortex. Importantly, when NAc β-catenin levels were downregulated by viral-mediated gene transfer, the therapeutic-like effects of URB597 were blocked. We suggest a potentially novel mechanism for the therapeutic-like effects of FAAH inhibition that is dependent on β-catenin activation in the NAc in a PTSD rat model.
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Chakraborty P, Chattarji S, Jeanneteau F. A salience hypothesis of stress in PTSD. Eur J Neurosci 2021; 54:8029-8051. [PMID: 34766390 DOI: 10.1111/ejn.15526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 09/13/2021] [Accepted: 10/30/2021] [Indexed: 11/30/2022]
Abstract
Attention to key features of contexts and things is a necessary tool for all organisms. Detecting these salient features of cues, or simply, salience, can also be affected by exposure to traumatic stress, as has been widely reported in individuals suffering from post-traumatic stress disorder (PTSD). Interestingly, similar observations have been robustly replicated across many animal models of stress as well. By using evidence from such rodent stress paradigms, in the present review, we explore PTSD through the lens of salience processing. In this context, we propose that interaction between the neurotrophin brain-derived neurotrophic factor (BDNF) and glucocorticoids determines the long lasting cellular and behavioural consequences of stress salience. We also describe the dual effect of glucocorticoid therapy in the amelioration of PTSD symptoms. Finally, by integrating in vivo observations at multiple scales of plasticity, we propose a unifying hypothesis that pivots on a crucial role of glucocorticoid signalling in dynamically orchestrating stress salience.
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Affiliation(s)
- Prabahan Chakraborty
- Institut de Genomique Fonctionnelle, University of Montpellier, Inserm, CNRS, Montpellier, 34090, France.,Tata Institute of Fundamental Research, National Centre for Biological Sciences, Bellary Road, Bangalore, 560065, India
| | - Sumantra Chattarji
- Tata Institute of Fundamental Research, National Centre for Biological Sciences, Bellary Road, Bangalore, 560065, India.,Centre for Brain Development and Repair, Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India.,Centre for Discovery Brain Sciences, Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh, UK
| | - Freddy Jeanneteau
- Institut de Genomique Fonctionnelle, University of Montpellier, Inserm, CNRS, Montpellier, 34090, France
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7
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Portugalov A, Akirav I. Do Adolescent Exposure to Cannabinoids and Early Adverse Experience Interact to Increase the Risk of Psychiatric Disorders: Evidence from Rodent Models. Int J Mol Sci 2021; 22:ijms22020730. [PMID: 33450928 PMCID: PMC7828431 DOI: 10.3390/ijms22020730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Revised: 01/09/2021] [Accepted: 01/12/2021] [Indexed: 12/30/2022] Open
Abstract
There have been growing concerns about the protracted effects of cannabis use in adolescents on emotion and cognition outcomes, motivated by evidence of growing cannabis use in adolescents, evidence linking cannabis use to various psychiatric disorders, and the increasingly perceived notion that cannabis is harmless. At the same time, studies suggest that cannabinoids may have therapeutic potential against the impacts of stress on the brain and behavior, and that young people sometimes use cannabinoids to alleviate feelings of depression and anxiety (i.e., “self-medication”). Exposure to early adverse life events may predispose individuals to developing psychopathology in adulthood, leading researchers to study the causality between early life factors and cognitive and emotional outcomes in rodent models and to probe the underlying mechanisms. In this review, we aim to better understand the long-term effects of cannabinoids administered in sensitive developmental periods (mainly adolescence) in rodent models of early life stress. We suggest that the effects of cannabinoids on emotional and cognitive function may vary between different sensitive developmental periods. This could potentially affect decisions regarding the use of cannabinoids in clinical settings during the early stages of development and could raise questions regarding educating the public as to potential risks associated with cannabis use.
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Affiliation(s)
- Anna Portugalov
- Department of Psychology, School of Psychological Sciences, University of Haifa, 3498838 Haifa, Israel;
- The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, 3498838 Haifa, Israel
| | - Irit Akirav
- Department of Psychology, School of Psychological Sciences, University of Haifa, 3498838 Haifa, Israel;
- The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, 3498838 Haifa, Israel
- Correspondence:
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8
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Potential application of endocannabinoid system agents in neuropsychiatric and neurodegenerative diseases-focusing on FAAH/MAGL inhibitors. Acta Pharmacol Sin 2020; 41:1263-1271. [PMID: 32203086 PMCID: PMC7608191 DOI: 10.1038/s41401-020-0385-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 02/15/2020] [Accepted: 02/19/2020] [Indexed: 01/01/2023] Open
Abstract
The endocannabinoid system (ECS) has received extensive attention for its neuroprotective effect on the brain. This system comprises endocannabinoids, endocannabinoid receptors, and the corresponding ligands and proteins. The molecular players involved in their regulation and metabolism are potential therapeutic targets for neuropsychiatric diseases including anxiety, depression and neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). The inhibitors of two endocannabinoid hydrolases, i.e., fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), have the capacity to increase the level of endocannabinoids indirectly, causing fewer side effects than those associated with direct supplementation of cannabinoids. Their antidepressant and anxiolytic mechanisms are considered to modulate the hypothalamic-pituitary-adrenal axis and regulate synaptic and neural plasticity. In terms of AD/PD, treatment with FAAH/MAGL inhibitors leads to reduction in amyloid β-protein deposition and inhibition of the death of dopamine neurons, which are commonly accepted to underlie the pathogenesis of AD and PD, respectively. Inflammation as the cause of depression/anxiety and PD/AD is also the target of FAAH/MAGL inhibitors. In this review, we summarize the application and involvement of FAAH/MAGL inhibitors in related neurological diseases. Focus on the latest research progress using FAAH/MAGL inhibitors is expected to facilitate the development of novel approaches with therapeutic potential.
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Rezaie M, Nasehi M, Vaseghi S, Alimohammadzadeh K, Islami Vaghar M, Mohammadi-Mahdiabadi-Hasani MH, Zarrindast MR. The interaction effect of sleep deprivation and cannabinoid type 1 receptor in the CA1 hippocampal region on passive avoidance memory, depressive-like behavior and locomotor activity in rats. Behav Brain Res 2020; 396:112901. [PMID: 32920013 DOI: 10.1016/j.bbr.2020.112901] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 09/03/2020] [Accepted: 09/03/2020] [Indexed: 12/19/2022]
Abstract
Increasing evidence shows the interaction effect of cannabinoids and sleep on cognitive functions. In the present study, we aimed to investigate the interaction effect of cannabinoids type 1 receptor (CB1r) in the CA1 hippocampal region and sleep deprivation (SD) on passive avoidance memory and depressive-like behavior in male Wistar rats. We used water box apparatus to induce total SD (TSD) for 24 h. The shuttle-box was applied to assess passive avoidance memory and locomotion apparatus was applied to assess locomotor activity. Forced swim test (FST) was used to evaluate rat's behavior. ACPA (CB1r agonist) at the doses of 0.01, 0.001 and 0.0001 μg/rat, and AM251 (CB1r antagonist) at the doses of 100, 10 and 1 ng/rat were injected intra-CA1, five minutes after training via stereotaxic surgery. Results showed SD impaired memory. ACPA at the doses of 0.01 and 0.001 μg/rat impaired memory and at all doses did not alter the effect of SD on memory. AM251 by itself did not alter memory, while at lowest dose (1 ng/rat) restored SD-induced memory deficit. Both drugs induced depressive-like behavior in a dose-dependent manner. Furthermore, both drugs decreased swimming at some doses (ACPA at 0.0001 μg/rat, AM251 at 0.001 and 0.01 ng/rat). Also, ACPA at the highest dose increased climbing of SD rats. In conclusion, we suggest CB1r may interact with the effect of SD on memory. Additionally, cannabinoids may show a dose-dependent manner in modulating mood and behavior. Interestingly, CB1r agonists and antagonists may exhibit a similar effect in some behavioral assessments.
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Affiliation(s)
- Maede Rezaie
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mohammad Nasehi
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.
| | - Salar Vaseghi
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran; Department of Cognitive Neuroscience, Institute for Cognitive Science Studies (ICSS), Tehran, Iran.
| | - Khalil Alimohammadzadeh
- Department of Health Services Management, North Tehran Branch, Islamic Azad University, Tehran, Iran; Health Economics Policy Research Center, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mohammad Islami Vaghar
- Department of Nursing, Faculity of Nursing and Midwifery, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | | | - Mohammad-Reza Zarrindast
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran; Department of Cognitive Neuroscience, Institute for Cognitive Science Studies (ICSS), Tehran, Iran; Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Department of Neuroendocrinology, Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran, Iran
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10
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Piette C, Cui Y, Gervasi N, Venance L. Lights on Endocannabinoid-Mediated Synaptic Potentiation. Front Mol Neurosci 2020; 13:132. [PMID: 32848597 PMCID: PMC7399367 DOI: 10.3389/fnmol.2020.00132] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 06/26/2020] [Indexed: 12/15/2022] Open
Abstract
The endocannabinoid (eCB) system is a lipid-based neurotransmitter complex that plays crucial roles in the neural control of learning and memory. The current model of eCB-mediated retrograde signaling is that eCBs released from postsynaptic elements travel retrogradely to presynaptic axon terminals, where they activate cannabinoid type-1 receptors (CB1Rs) and ultimately decrease neurotransmitter release on a short- or long-term scale. An increasing body of evidence has enlarged this view and shows that eCBs, besides depressing synaptic transmission, are also able to increase neurotransmitter release at multiple synapses of the brain. This indicates that eCBs act as bidirectional regulators of synaptic transmission and plasticity. Recently, studies unveiled links between the expression of eCB-mediated long-term potentiation (eCB-LTP) and learning, and between its dysregulation and several pathologies. In this review article, we first distinguish the various forms of eCB-LTP based on their mechanisms, resulting from homosynaptically or heterosynaptically-mediated processes. Next, we consider the neuromodulation of eCB-LTP, its behavioral impact on learning and memory, and finally, eCB-LTP disruptions in various pathologies and its potential as a therapeutic target in disorders such as stress coping, addiction, Alzheimer’s and Parkinson’s disease, and pain. Cannabis is gaining popularity as a recreational substance as well as a medicine, and multiple eCB-based drugs are under development. In this context, it is critical to understand eCB-mediated signaling in its multi-faceted complexity. Indeed, the bidirectional nature of eCB-based neuromodulation may offer an important key to interpret the functions of the eCB system and how it is impacted by cannabis and other drugs.
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Affiliation(s)
- Charlotte Piette
- Center for Interdisciplinary Research in Biology, College de France, INSERM U1050, CNRS UMR7241, Labex Memolife, Paris, France
| | - Yihui Cui
- Department of Neurobiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Nicolas Gervasi
- Center for Interdisciplinary Research in Biology, College de France, INSERM U1050, CNRS UMR7241, Labex Memolife, Paris, France
| | - Laurent Venance
- Center for Interdisciplinary Research in Biology, College de France, INSERM U1050, CNRS UMR7241, Labex Memolife, Paris, France
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11
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Sbarski B, Akirav I. Cannabinoids as therapeutics for PTSD. Pharmacol Ther 2020; 211:107551. [PMID: 32311373 DOI: 10.1016/j.pharmthera.2020.107551] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 03/08/2020] [Indexed: 02/09/2023]
Abstract
Post-traumatic stress disorder (PTSD) is a complex disorder that involves dysregulation of multiple neurobiological systems. The traumatic stressor plays a causal role in producing psychological dysfunction and the pattern of findings suggests that the hypothalamic-pituitary-adrenal (HPA) axis, which is instrumental for stress adaptation, is critically dysfunctional in PTSD. Given the lack of understanding of the basic mechanisms and underlying pathways that cause the disorder and its heterogeneity, PTSD poses challenges for treatment. Targeting the endocannabinoid (ECB) system to treat mental disorders, and PTSD in particular, has been the focus of research and interest in recent years. The ECB system modulates multiple functions, and drugs enhancing ECB signaling have shown promise as potential therapeutic agents in stress effects and other psychiatric and medical conditions. In this review, we focus on the interaction between the ECB-HPA systems in animal models for PTSD and in patients with PTSD. We summarize evidence supporting the use of cannabinoids in preventing and treating PTSD in preclinical and clinical studies. As the HPA system plays a key role in the mediation of the stress response and the pathophysiology of PTSD, we describe preclinical studies suggesting that enhancing ECB signaling is consistent with decreasing PTSD symptoms and dysfunction of the HPA axis. Overall, we suggest that a pharmacological treatment targeted at one system (e.g., HPA) may not be very effective because of the heterogeneity of the disorder. There are abnormalities across different neurotransmitter systems in the pathophysiology of PTSD and none of these systems function uniformly among all patients with PTSD. Hence, conceptually, enhancing ECB signaling may be a more effective avenue for pharmacological treatment.
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Affiliation(s)
- Brenda Sbarski
- School of Psychological Sciences, Integrated Brain and Behavior Research Center, University of Haifa, Haifa 3498838, Israel
| | - Irit Akirav
- School of Psychological Sciences, Integrated Brain and Behavior Research Center, University of Haifa, Haifa 3498838, Israel.
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12
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Vimalanathan A, Gidyk DC, Diwan M, Gouveia FV, Lipsman N, Giacobbe P, Nobrega JN, Hamani C. Endocannabinoid modulating drugs improve anxiety but not the expression of conditioned fear in a rodent model of post-traumatic stress disorder. Neuropharmacology 2020; 166:107965. [PMID: 31962287 DOI: 10.1016/j.neuropharm.2020.107965] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 01/07/2020] [Accepted: 01/12/2020] [Indexed: 12/23/2022]
Abstract
The endocannabinoid (eCB) system is a potential target for the treatment of symptoms of post-traumatic stress disorder (PTSD). Similar to clinical PTSD, approximately 25-30% of rats that undergo cued fear conditioning exhibit impaired extinction learning. In addition to extinction-resistant fear, these "weak extinction" (WE) rats show persistent anxiety-like behaviors. The goal of the present study was to test the hypothesis that behavioural differences between WE animals and those presenting normal extinction patterns (strong extinction; SE) could be mediated by the eCB system. Rats undergoing fear conditioning/extinction and fear recall sessions were initially segregated in weak and strong-extinction groups. Two weeks later, animals underwent a fear recall session followed by a novelty-suppressed feeding (NSF) test. In acute experiments, WE rats were injected with either the fatty acid amide hydrolase (FAAH) inhibitor URB597 or the CB1 agonist WIN55,212-2 1 h prior to long-term recall and NSF testing. SE animals were injected with the inverse CB1 receptor agonist AM251. In chronic experiments, WE and SE rats were given daily injections of URB597 or AM251 between short and long-term recall sessions. We found that acute administration of WIN55,212-2 but not URB597 reduced anxiety-like behaviour in WE rats. In contrast, AM251 was anxiogenic in SE animals. Neither treatment was effective in altering freezing expression during fear recall. The chronic administration of AM251 to SE or URB597 to WE did not alter fear or anxiety-like behaviour or changed the expression of FAAH and CB1. Together, these results suggest that systemic manipulations of the eCB system may alter anxiety-like behaviour but not the behavioural expression of an extinction-resistant associative fear memory.
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Affiliation(s)
- Akshayan Vimalanathan
- Harquail Centre for Neuromodulation, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, ON, M4N 3M5, Canada; Behavioural Neurobiology Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada
| | - Darryl C Gidyk
- Harquail Centre for Neuromodulation, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, ON, M4N 3M5, Canada
| | - Mustansir Diwan
- Harquail Centre for Neuromodulation, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, ON, M4N 3M5, Canada
| | - Flavia V Gouveia
- Harquail Centre for Neuromodulation, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, ON, M4N 3M5, Canada
| | - Nir Lipsman
- Harquail Centre for Neuromodulation, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, ON, M4N 3M5, Canada
| | - Peter Giacobbe
- Harquail Centre for Neuromodulation, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, ON, M4N 3M5, Canada
| | - José N Nobrega
- Behavioural Neurobiology Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada
| | - Clement Hamani
- Harquail Centre for Neuromodulation, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, ON, M4N 3M5, Canada; Behavioural Neurobiology Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada.
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13
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Nerve growth factor against PTSD symptoms: Preventing the impaired hippocampal cytoarchitectures. Prog Neurobiol 2020; 184:101721. [DOI: 10.1016/j.pneurobio.2019.101721] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 10/11/2019] [Accepted: 11/02/2019] [Indexed: 01/19/2023]
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14
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Maymon N, Mizrachi Zer-Aviv T, Sabban EL, Akirav I. Neuropeptide Y and cannabinoids interaction in the amygdala after exposure to shock and reminders model of PTSD. Neuropharmacology 2019; 162:107804. [PMID: 31622603 DOI: 10.1016/j.neuropharm.2019.107804] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 09/23/2019] [Accepted: 09/28/2019] [Indexed: 12/14/2022]
Abstract
Modulation of cannabinoid and neuropeptide Y (NPY) receptors may offer therapeutic benefits for post-traumatic stress disorder (PTSD). In this study, we aimed to investigate the functional interaction between these systems in the basolateral amygdala (BLA) in a rat model of PTSD. Rats were exposed to the shock and reminders model of PTSD and tested for hyper arousal/PTSD- and depression-like behaviors 3 weeks later. Immediately after shock exposure rats were microinjected into the BLA with URB597, a selective inhibitor of fatty acid amide hydrolase (FAAH) that increases the levels of the endocannabinoid anandamide or with the NPY1 receptor agonist Leu31,Pro34-NPY (Leu). Intra-BLA URB597 prevented the shock/reminders-induced PTSD- behaviors (extinction, startle) and depression-behaviors (despair, social impairments). These preventing effects of URB597 on PTSD- and depression-like behaviors were shown to be mostly mediated by cannabinoid CB1 and NPY1 receptors, as they were blocked when URB597 was co-administered with a low dose of a CB1 or NPY1 receptor antagonist. Similarly, intra-BLA Leu prevented development of all the behaviors. Interestingly, a CB1 antagonist prevented the effects of Leu on despair and social behavior, but not the effects on extinction and startle. Moreover, exposure to shock and reminders upregulated CB1 and NPY1 receptors in the BLA and infralimbic prefrontal cortex and this upregulation was restored to normal with intra-BLA URB597 or Leu. The findings suggest that the functional interaction between the eCB and NPY1 systems is complex and provide a rationale for exploring novel therapeutic strategies that target the cannabinoid and NPY systems for stress-related diseases.
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Affiliation(s)
- Neta Maymon
- Department of Psychology, University of Haifa, Haifa, 3498838, Israel
| | | | - Esther L Sabban
- Department of Biochemistry and Molecular Biology, New York Medical College Valhalla, New York, 10595, USA
| | - Irit Akirav
- Department of Psychology, University of Haifa, Haifa, 3498838, Israel.
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15
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Chen J, Shu S, Chen Y, Liu Z, Yu L, Yang L, Xu Y, Zhang M. AIM2 deletion promotes neuroplasticity and spatial memory of mice. Brain Res Bull 2019; 152:85-94. [DOI: 10.1016/j.brainresbull.2019.07.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 06/18/2019] [Accepted: 07/08/2019] [Indexed: 11/16/2022]
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16
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Ney LJ, Matthews A, Bruno R, Felmingham KL. Cannabinoid interventions for PTSD: Where to next? Prog Neuropsychopharmacol Biol Psychiatry 2019; 93:124-140. [PMID: 30946942 DOI: 10.1016/j.pnpbp.2019.03.017] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 03/20/2019] [Accepted: 03/29/2019] [Indexed: 01/18/2023]
Abstract
Cannabinoids are a promising method for pharmacological treatment of post-traumatic stress disorder (PTSD). Despite considerable research devoted to the effect of cannabinoid modulation on PTSD symptomology, there is not a currently agreed way by which the cannabinoid system should be targeted in humans. In this review, we present an overview of recent research identifying neurological pathways by which different cannabinoid-based treatments may exert their effects on PTSD symptomology. We evaluate the strengths and weaknesses of each of these different approaches, including recent challenges presented to favourable options such as fatty acid amide hydrolase (FAAH) inhibitors. This article makes the strengths and challenges of different potential cannabinoid treatments accessible to psychological researchers interested in cannabinoid therapeutics and aims to aid selection of appropriate tools for future clinical trials.
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Affiliation(s)
- Luke J Ney
- School of Psychology, University of Tasmania, Australia.
| | | | | | - Kim L Felmingham
- School of Psychological Sciences, University of Melbourne, Australia
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17
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Xue F, Xue SS, Liu L, Sang HF, Ma QR, Tan QR, Wang HN, Zhou CH, Peng ZW. Early intervention with electroacupuncture prevents PTSD-like behaviors in rats through enhancing hippocampal endocannabinoid signaling. Prog Neuropsychopharmacol Biol Psychiatry 2019; 93:171-181. [PMID: 30946940 DOI: 10.1016/j.pnpbp.2019.03.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 03/20/2019] [Accepted: 03/29/2019] [Indexed: 12/14/2022]
Abstract
Electroacupuncture (EA) is a clinically useful physiological therapy that has been recently adopted to treat several brain disorders. However, the potential role of early EA intervention in the prevention of posttraumatic stress disorder (PTSD) as well as its potential cellular and molecular mechanism has never been investigated previously. In the present study, we used an enhanced single prolonged stress (ESPS) model to access the effects of early EA intervention on the prevention of anxiety-like and fear learning behaviors, as well as the influence of the expression of post-synaptic density protein 95 (PSD95), synaptophysin (Syn), brain derived neurotrophic factor (BDNF), diacylglycerol lipase alpha (DAGLα) and cannabinoid type 1 receptor (CB1R) in the hippocampus with or without DAGLα or CB1R knockdown by a short hairpin RNA (shRNA) in the hippocampus. Moreover, the effects of electrical stimulation with different parameters on the expression of DAGLα and CB1R in the hippocampal astrocytes were also observed. The results showed that Early EA intervention improved hippocampal synaptic plasticity and ameliorated PTSD-like behaviors and also increased expression of BDNF, DAGLα and CB1R. However, either DAGLα or CB1R knockdown by a short hairpin RNA (shRNA) eliminated the neuroprotective effects of early EA intervention. Furthermore, electrical stimulation with 2/15 Hz 1 mA elevated the expression of DAGLα and CB1R. Altogether, our findings provide new insights regarding the possibility of using early EA intervention in the prevention of PTSD, and the protective effects of EA is involving the activation of DAGLα and CB1R.
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Affiliation(s)
- Fen Xue
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Shan-Shan Xue
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Ling Liu
- Institution of Neuroscience, Fourth Military Medical University, Xi'an 710032, China
| | - Han-Fei Sang
- Department of Anesthesiology, Xiang'an Hospital, Xiamen University, Xiamen 361101, China
| | - Quan-Rui Ma
- Department of Human Anatomy and Histology and Embryology, Basic Medical College, Ningxia Medical University, Yinchuan 750004, China
| | - Qing-Rong Tan
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Hua-Ning Wang
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Cui-Hong Zhou
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
| | - Zheng-Wu Peng
- Department of Psychiatry, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
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18
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Lisboa SF, Vila-Verde C, Rosa J, Uliana DL, Stern CAJ, Bertoglio LJ, Resstel LB, Guimaraes FS. Tempering aversive/traumatic memories with cannabinoids: a review of evidence from animal and human studies. Psychopharmacology (Berl) 2019; 236:201-226. [PMID: 30604182 DOI: 10.1007/s00213-018-5127-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 11/14/2018] [Indexed: 01/08/2023]
Abstract
RATIONALE Aversive learning and memory are essential to cope with dangerous and stressful stimuli present in an ever-changing environment. When this process is dysfunctional, however, it is associated with posttraumatic stress disorder (PTSD). The endocannabinoid (eCB) system has been implicated in synaptic plasticity associated with physiological and pathological aversive learning and memory. OBJECTIVE AND METHODS The objective of this study was to review and discuss evidence on how and where in the brain genetic or pharmacological interventions targeting the eCB system would attenuate aversive/traumatic memories through extinction facilitation in laboratory animals and humans. The effect size of the experimental intervention under investigation was also calculated. RESULTS Currently available data indicate that direct or indirect activation of cannabinoid type-1 (CB1) receptor facilitates the extinction of aversive/traumatic memories. Activating CB1 receptors around the formation of aversive/traumatic memories or their reminders can potentiate their subsequent extinction. In most cases, the effect size has been large (Cohen's d ≥ 1.0). The brain areas responsible for the abovementioned effects include the medial prefrontal cortex, amygdala, and/or hippocampus. The potential role of cannabinoid type-2 (CB2) receptors in extinction learning is now under investigation. CONCLUSION Drugs augmenting the brain eCB activity can temper the impact of aversive/traumatic experiences by diverse mechanisms depending on the moment of their administration. Considering the pivotal role the extinction process plays in PTSD, the therapeutic potential of these drugs is evident. The sparse number of clinical trials testing these compounds in stress-related disorders is a gap in the literature that needs to be addressed.
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Affiliation(s)
- Sabrina F Lisboa
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo (FMRP/USP), Av Bandeirantes 3900, Monte Alegre, 14049900, Ribeirão Preto, São Paulo, Brazil. .,Center for Interdisciplinary Research on Applied Neurosciences (NAPNA), Medical School of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil.
| | - C Vila-Verde
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo (FMRP/USP), Av Bandeirantes 3900, Monte Alegre, 14049900, Ribeirão Preto, São Paulo, Brazil.,Center for Interdisciplinary Research on Applied Neurosciences (NAPNA), Medical School of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - J Rosa
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo (FMRP/USP), Av Bandeirantes 3900, Monte Alegre, 14049900, Ribeirão Preto, São Paulo, Brazil.,Center for Interdisciplinary Research on Applied Neurosciences (NAPNA), Medical School of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - D L Uliana
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo (FMRP/USP), Av Bandeirantes 3900, Monte Alegre, 14049900, Ribeirão Preto, São Paulo, Brazil.,Center for Interdisciplinary Research on Applied Neurosciences (NAPNA), Medical School of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - C A J Stern
- Department of Pharmacology, Federal University of Parana, Curitiba, PR, Brazil
| | - L J Bertoglio
- Department of Pharmacology, Federal University of Santa Catarina, Florianopolis, SC, Brazil
| | - L B Resstel
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo (FMRP/USP), Av Bandeirantes 3900, Monte Alegre, 14049900, Ribeirão Preto, São Paulo, Brazil.,Center for Interdisciplinary Research on Applied Neurosciences (NAPNA), Medical School of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - F S Guimaraes
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo (FMRP/USP), Av Bandeirantes 3900, Monte Alegre, 14049900, Ribeirão Preto, São Paulo, Brazil.,Center for Interdisciplinary Research on Applied Neurosciences (NAPNA), Medical School of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
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19
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Modulation of the endocannabinoid system by sex hormones: Implications for posttraumatic stress disorder. Neurosci Biobehav Rev 2018; 94:302-320. [DOI: 10.1016/j.neubiorev.2018.07.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 07/10/2018] [Accepted: 07/10/2018] [Indexed: 12/11/2022]
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20
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Role of endocannabinoids in the hippocampus and amygdala in emotional memory and plasticity. Neuropsychopharmacology 2018; 43:2017-2027. [PMID: 29977073 PMCID: PMC6098035 DOI: 10.1038/s41386-018-0135-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 06/19/2018] [Accepted: 06/21/2018] [Indexed: 12/13/2022]
Abstract
Posttraumatic stress disorder (PTSD) is characterized by the reexperiencing of a traumatic event and is associated with slower extinction of fear responses. Impaired extinction of fearful associations to trauma-related cues may interfere with treatment response, and extinction deficits may be premorbid risk factors for the development of PTSD. We examined the effects of exposure to a severe footshock followed by situational reminders (SRs) on extinction, plasticity, and endocannabinoid (eCB) content and activity in the hippocampal CA1 area and basolateral amygdala (BLA). We also examined whether enhancing eCB signaling before extinction, using the fatty acid amide hydrolase (FAAH) inhibitor URB597, could prevent the shock/SRs-induced effects on fear response and plasticity. URB597 administered systemically (0.3 mg/kg) or locally into the CA1 or BLA (0.1 µg/side) prior to extinction decreased fear retrieval and this effect persisted throughout extinction training and did not recuperate during spontaneous recovery. A low dose of the CB1 receptor antagonist AM251 (0.3 mg/kg i.p. or 0.01 µg/0.5 µl intra-CA1 or intra-BLA) blocked these effects suggesting that the effects of URB597 were CB1 receptor-dependent. Exposure to shock and reminders induced behavioral metaplasticity with opposite effects on long-term potentiation (LTP) in the hippocampus (impairment) and the BLA (enhancement). URB597 was found to prevent the opposite shock/SR-induced metaplasticity in hippocampal and BLA-LTP. Exposure to shock and reminders might cause variation in endogenous cannabinoid levels that could affect fear-circuit function. Indeed, exposure to shock and SRs affected eCB content: increased 2-arachidonoyl-glycerol (2-AG) and N-arachidonylethanolamine (AEA) levels in the CA1, decreased serum and BLA AEA levels while shock exposure increased FAAH activity in the CA1 and BLA. FAAH inhibition before extinction abolished fear and modulated LTP in the hippocampus and amygdala, brain regions pertinent to emotional memory. The findings suggest that targeting the eCB system before extinction may be beneficial in fear memory attenuation and these effects may involve metaplasticity in the CA1 and BLA.
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21
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Sbarski B, Akirav I. Chronic exposure to cannabinoids before an emotional trauma may have negative effects on emotional function. Eur Neuropsychopharmacol 2018; 28:955-969. [PMID: 30026011 DOI: 10.1016/j.euroneuro.2018.05.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 05/09/2018] [Accepted: 05/17/2018] [Indexed: 01/26/2023]
Abstract
Chronic direct activation of cannabinoid CB1 receptors (CB1r) may lead to downregulation of CB1r which may in turn result in a depression-like phenotype in certain individuals. We examined the effects of chronic cannabinoid receptor activation before exposure to an emotional traumatic event on CB1r expression in the basolateral amygdala (BLA) and CA1 and on protracted anxiety- and depression-like behaviors. We used exposure to severe shock and situational reminders (SRs) in an inhibitory apparatus as a model for emotional trauma. Chronic treatment with the CB1/2 receptor agonist WIN55,212-2 (1.2 mg/kg, i.p.) before shock exposure had differential effects on depression- and anxiety-like behavioral measures depending on withdrawal periods. In the 24 hrs withdrawal condition, WIN55,212-2 enhanced fear retrieval and impaired extinction, increased anhedonia and despair, but had a therapeutic effect in the startle test. In the 10 days withdrawal condition, WIN55,212-2 enhanced fear retrieval and impaired extinction without preventing the shock/SR-induced negative effects on anhedonia or startle response, but had a therapeutic effect in the despair test. Chronic treatment with WIN55,212-2 was found to down regulate CB1r protein levels in the BLA in the 10 days withdrawal condition, and to upregulate CB1r protein levels in the 24 hrs condition. In the CA1, rats chronically injected with vehicle or WIN55,212-2 demonstrated downregulation of CB1r protein levels. Chronic exposure to cannabinoids prior to an emotional trauma may have deleterious effects on emotional function suggesting that direct CB1/2 receptor activation may not be an optimal way to manipulate the endocannabinoid system in stressful individuals.
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Affiliation(s)
- Brenda Sbarski
- Department of Psychology, University of Haifa, Haifa 3498838, Israel
| | - Irit Akirav
- Department of Psychology, University of Haifa, Haifa 3498838, Israel.
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22
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Burstein O, Shoshan N, Doron R, Akirav I. Cannabinoids prevent depressive-like symptoms and alterations in BDNF expression in a rat model of PTSD. Prog Neuropsychopharmacol Biol Psychiatry 2018; 84:129-139. [PMID: 29458190 DOI: 10.1016/j.pnpbp.2018.01.026] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 01/17/2018] [Accepted: 01/29/2018] [Indexed: 11/29/2022]
Abstract
Posttraumatic stress disorder (PTSD) is a debilitating condition highly comorbid with depression. The endocannabinoid (eCB) system and brain-derived neurotrophic factor (BDNF) are suggestively involved in both disorders. We examined whether cannabinoids can prevent the long-term depressive-like symptoms induced by exposure to the shock and situational reminders (SRs) model of PTSD. The CB1/2 receptor agonist WIN55,212-2 (0.5 mg/kg; i.p.), the fatty acid hydrolase (FAAH) inhibitor URB597 (0.3 mg/kg, i.p.) or vehicle were administered 2 h after severe shock. Cannabinoids prevented the shock/SRs-induced alterations in social recognition memory, locomotion, passive coping, anxiety-like behavior, anhedonia, fear retrieval, fear extinction and startle response as well as the decrease in BDNF levels in the hippocampus and prefrontal cortex (PFC). Furthermore, significant correlations were found between depressive-like behaviors and BDNF levels in the brain. The findings suggest that cannabinoids may prevent both depressive- and PTSD-like symptoms following exposure to severe stress and that alterations in BDNF levels in the brains' fear circuit are involved in these effects.
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Affiliation(s)
- Or Burstein
- School of Behavioral Science, The Academic College Tel-Aviv-Yaffo, Tel-Aviv, Israel
| | - Noa Shoshan
- Department of Psychology, University of Haifa, Haifa 3498838, Israel
| | - Ravid Doron
- School of Behavioral Science, The Academic College Tel-Aviv-Yaffo, Tel-Aviv, Israel
| | - Irit Akirav
- Department of Psychology, University of Haifa, Haifa 3498838, Israel.
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23
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Fidelman S, Mizrachi Zer-Aviv T, Lange R, Hillard CJ, Akirav I. Chronic treatment with URB597 ameliorates post-stress symptoms in a rat model of PTSD. Eur Neuropsychopharmacol 2018. [PMID: 29519609 DOI: 10.1016/j.euroneuro.2018.02.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Activating the endocannabinoid system has become a major focus in the search for novel therapeutics for anxiety and deficits in fear extinction, two defining features of PTSD. We examined whether chronic treatment with the fatty acid amide hydrolase (FAAH) inhibitor URB597 (0.2, 0.3, 0.4 mg/kg, i.p.) or the CB1/2 receptor agonist WIN55,212-2 (0.25, 0.5 mg/kg, i.p.) injected for 3 weeks to rats exposed to the shock and reminders model of PTSD would attenuate post-stress symptoms and affect basolateral amygdala (BLA) and CA1 CB1 receptors. Exposure to shock and reminders enhanced acoustic startle response and impaired extinction. Rats exposed to shock and reminders and chronically treated with URB597 demonstrated normalized startle response and intact extinction kinetics. WIN55,212-2 only affected the startle response. The therapeutic effects of URB597 and WIN55,212-2 were found to be CB1 receptor dependent, as these effects were blocked when a low dose of the CB1 receptor antagonist AM251 (0.3 mg/kg, i.p. for 3 weeks) was co-administered. Moreover, URB597, but not WIN55,212-2, normalized the shock/reminders-induced upregulation in CB1 receptor levels in the BLA and CA1. One hour after the shock, N-arachidonoylethanolamine (AEA) was increased in the BLA and decreased in the CA1. Circulating 2-arachidonoylglycerol (2-AG) concentrations were decreased in shocked rats, with no significant effect in the BLA or CA1. FAAH activity was increased in the CA1 of shocked rats. Chronic cannabinoid treatment with URB597 can ameliorate PTSD-like symptoms suggesting FAAH inhibitors as a potentially effective therapeutic strategy for the treatment of disorders associated with inefficient fear coping.
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MESH Headings
- Amidohydrolases/antagonists & inhibitors
- Amidohydrolases/metabolism
- Animals
- Arachidonic Acids/blood
- Basolateral Nuclear Complex/metabolism
- Benzamides/administration & dosage
- Benzamides/pharmacology
- Benzoxazines/administration & dosage
- Benzoxazines/pharmacology
- CA1 Region, Hippocampal/metabolism
- Cannabinoid Receptor Antagonists/pharmacology
- Carbamates/administration & dosage
- Carbamates/pharmacology
- Dose-Response Relationship, Drug
- Electric Stimulation
- Endocannabinoids/blood
- Endocannabinoids/metabolism
- Extinction, Psychological/drug effects
- Glycerides/blood
- Male
- Morpholines/administration & dosage
- Morpholines/pharmacology
- Naphthalenes/administration & dosage
- Naphthalenes/pharmacology
- Piperidines/pharmacology
- Polyunsaturated Alkamides
- Pyrazoles/pharmacology
- Rats
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/physiology
- Reflex, Startle/drug effects
- Reflex, Startle/physiology
- Stress Disorders, Post-Traumatic/drug therapy
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Affiliation(s)
- Sharon Fidelman
- Department of Psychology, University of Haifa, Haifa 3498838, Israel
| | | | - Rachel Lange
- Department of Pharmacology and Toxicology, Neuroscience Research Center, Medical College of Wisconsin, Milwaukee 53226, USA
| | - Cecilia J Hillard
- Department of Pharmacology and Toxicology, Neuroscience Research Center, Medical College of Wisconsin, Milwaukee 53226, USA
| | - Irit Akirav
- Department of Psychology, University of Haifa, Haifa 3498838, Israel.
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24
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Enhancing Endocannabinoid Neurotransmission Augments The Efficacy of Extinction Training and Ameliorates Traumatic Stress-Induced Behavioral Alterations in Rats. Neuropsychopharmacology 2018; 43:1284-1296. [PMID: 29265107 PMCID: PMC5916373 DOI: 10.1038/npp.2017.305] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 12/09/2017] [Accepted: 12/15/2017] [Indexed: 12/19/2022]
Abstract
Exposure to a traumatic event may result in the development of post-traumatic stress disorder (PTSD). Endocannabinoids are crucial modulators of the stress response, interfere with excessive retrieval and facilitate the extinction of traumatic memories. Exposure therapy, combined with pharmacotherapy, represents a promising tool for PTSD treatment. We investigated whether pharmacological manipulations of the endocannabinoid system during extinction learning ameliorates the behavioral changes induced by trauma exposure. Rats were exposed to inescapable footshocks paired with social isolation, a risk factor for PTSD. One week after trauma, rats were subjected to three spaced extinction sessions, mimicking human exposure therapy. The anandamide hydrolysis inhibitor URB597, the 2-arachidonoylglycerol hydrolysis inhibitor JZL184 or the cannabinoid agonist WIN55,212-2 were administered before or after the extinction sessions. Rats were tested for extinction retention 16 or 36 days after trauma and 24-h later for social interaction. Extinction training alone reduced fear of the trauma-associated context but did not restore normal social interaction. Traumatized animals not exposed to extinction sessions exhibited reductions in hippocampal anandamide content with respect to home-cage controls. Noteworthy, all drugs exerted beneficial effects, but URB597 (0.1 mg/kg) induced the best improvements by enhancing extinction consolidation and restoring normal social behavior in traumatized rats through indirect activation of CB1 receptors. The ameliorating effects remained stable long after treatment and trauma exposure. Our findings suggest that drugs potentiating endocannabinoid neurotransmission may represent promising tools when combined to exposure-based psychotherapies in the treatment of PTSD.
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25
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Scarante FF, Vila-Verde C, Detoni VL, Ferreira-Junior NC, Guimarães FS, Campos AC. Cannabinoid Modulation of the Stressed Hippocampus. Front Mol Neurosci 2017; 10:411. [PMID: 29311804 PMCID: PMC5742214 DOI: 10.3389/fnmol.2017.00411] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 11/27/2017] [Indexed: 12/31/2022] Open
Abstract
Exposure to stressful situations is one of the risk factors for the precipitation of several psychiatric disorders, including Major Depressive Disorder, Posttraumatic Stress Disorder and Schizophrenia. The hippocampal formation is a forebrain structure highly associated with emotional, learning and memory processes; being particularly vulnerable to stress. Exposure to stressful stimuli leads to neuroplastic changes and imbalance between inhibitory/excitatory networks. These changes have been associated with an impaired hippocampal function. Endocannabinoids (eCB) are one of the main systems controlling both excitatory and inhibitory neurotransmission, as well as neuroplasticity within the hippocampus. Cannabinoids receptors are highly expressed in the hippocampus, and several lines of evidence suggest that facilitation of cannabinoid signaling within this brain region prevents stress-induced behavioral changes. Also, chronic stress modulates hippocampal CB1 receptors expression and endocannabinoid levels. Moreover, cannabinoids participate in mechanisms related to synaptic plasticity and adult neurogenesis. Here, we discussed the main findings supporting the involvement of hippocampal cannabinoid neurotransmission in stress-induced behavioral and neuroplastic changes.
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Affiliation(s)
- Franciele F Scarante
- Department of Pharmacology, School of Medicine of Ribeirão Preto, Centre for Interdisciplinary Research on Applied Neurosciences (NAPNA), Cannabinoid Research Institute, University of São Paulo, São Paulo, Brazil
| | - Carla Vila-Verde
- Department of Pharmacology, School of Medicine of Ribeirão Preto, Centre for Interdisciplinary Research on Applied Neurosciences (NAPNA), Cannabinoid Research Institute, University of São Paulo, São Paulo, Brazil
| | - Vinícius L Detoni
- Department of Pharmacology, School of Medicine of Ribeirão Preto, Centre for Interdisciplinary Research on Applied Neurosciences (NAPNA), Cannabinoid Research Institute, University of São Paulo, São Paulo, Brazil
| | - Nilson C Ferreira-Junior
- Department of Pharmacology, School of Medicine of Ribeirão Preto, Centre for Interdisciplinary Research on Applied Neurosciences (NAPNA), Cannabinoid Research Institute, University of São Paulo, São Paulo, Brazil
| | - Francisco S Guimarães
- Department of Pharmacology, School of Medicine of Ribeirão Preto, Centre for Interdisciplinary Research on Applied Neurosciences (NAPNA), Cannabinoid Research Institute, University of São Paulo, São Paulo, Brazil
| | - Alline C Campos
- Department of Pharmacology, School of Medicine of Ribeirão Preto, Centre for Interdisciplinary Research on Applied Neurosciences (NAPNA), Cannabinoid Research Institute, University of São Paulo, São Paulo, Brazil
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