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Lookfong NA, Raup-Konsavage WM, Silberman Y. Potential Utility of Cannabidiol in Stress-Related Disorders. Cannabis Cannabinoid Res 2022; 8:230-240. [PMID: 36409719 PMCID: PMC10061337 DOI: 10.1089/can.2022.0130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Background: The endocannabinoid (eCB) system plays an important role in homeostatic regulation of anxiety and stress responses; however, the eCB system can be disrupted following traumatic stressors. Additionally, traumatic or chronic stressors that occur during adulthood or early life can cause long-lasting disturbances in the eCB system. These alterations interfere with hypothalamic-pituitary-adrenal axis function and may be involved in lifelong increased fear and anxiety behaviors as well as increased risk for development of post-traumatic stress disorder (PTSD). Methods: This review focuses on the implications of trauma and significant stressors on eCB functionality and neural pathways, both in adolescence and into adulthood, as well as the current state of testing for CBD efficacy in treating pediatric and adult patients suffering from stress-induced eCB dysregulation. Articles were searched via Pubmed and included studies examining eCB modulation of stress-related disorders in both clinical settings and preclinical models. Conclusion: Given the potential for lifelong alterations in eCB signaling that can mediate stress responsiveness, consideration of pharmaceutical or nutraceutical agents that impact eCB targets may improve clinical outcomes in stress-related disorders. However, caution may be warranted in utilization of medicinal cannabinoid products that contain delta-9-tetrahydrocannabinol due to pronounced euphorigenic effects and potential to exacerbate stress-related behaviors. Other cannabinoid products, such as cannabidiol (CBD), have shown promise in reducing stress-related behaviors in pre-clinical models. Overall, pre-clinical evidence supports CBD as a potential treatment for stress or anxiety disorders resulting from previously stressful events, particularly by reducing fearful behavior and promoting extinction of contextual fear memories, which are hallmarks of PTSD. However, very limited clinical research has been conducted examining the potential effectiveness of CBD in this regard and should be examined further.
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Affiliation(s)
- Nicole A. Lookfong
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | | | - Yuval Silberman
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, Pennsylvania, USA
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2
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Simone JJ, Green MR, McCormick CM. Endocannabinoid system contributions to sex-specific adolescent neurodevelopment. Prog Neuropsychopharmacol Biol Psychiatry 2022; 113:110438. [PMID: 34534603 DOI: 10.1016/j.pnpbp.2021.110438] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 08/13/2021] [Accepted: 09/08/2021] [Indexed: 01/08/2023]
Abstract
With an increasing number of countries and states adopting legislation permitting the use of cannabis for medical purposes, there is a growing interest among health and research professionals into the system through which cannabinoids principally act, the endocannabinoid system (ECS). Much of the seminal research into the ECS dates back only 30 years and, although there has been tremendous development within the field during this time, many questions remain. More recently, investigations have emerged examining the contributions of the ECS to normative development and the effect of altering this system during important critical periods. One such period is adolescence, a unique period during which brain and behaviours are maturing and reorganizing in preparation for adulthood, including shifts in endocannabinoid biology. The purpose of this review is to discuss findings to date regarding the maturation of the ECS during adolescence and the consequences of manipulations of the ECS during this period to normative neurodevelopmental processes, as well as highlight sex differences in ECS function, important technical considerations, and future directions. Because most of what we know is derived from preclinical studies on rodents, we provide relevant background of this model and some commentary on the translational relevance of the research in this area.
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Affiliation(s)
- Jonathan J Simone
- Department of Biological Sciences, 1812 Sir Isaac Brock Way, Brock University, St. Catharines, ON L2S 3A1, Canada; Centre for Neuroscience, 1812 Sir Isaac Brock Way, Brock University, St. Catharines, ON L2S 3A1, Canada; Huxley Health Inc., 8820 Jane St., Concord, ON, L4K 2M9, Canada; eCB Consulting Inc., PO Box 652, 3 Cameron St. W., Cannington, ON L0E 1E0, Canada; Medical Cannabis Canada, 601-3500 Lakeshore Rd. W., Oakville, ON L6L 0B4, Canada.
| | - Matthew R Green
- eCB Consulting Inc., PO Box 652, 3 Cameron St. W., Cannington, ON L0E 1E0, Canada; Medical Cannabis Canada, 601-3500 Lakeshore Rd. W., Oakville, ON L6L 0B4, Canada.
| | - Cheryl M McCormick
- Department of Biological Sciences, 1812 Sir Isaac Brock Way, Brock University, St. Catharines, ON L2S 3A1, Canada; Centre for Neuroscience, 1812 Sir Isaac Brock Way, Brock University, St. Catharines, ON L2S 3A1, Canada; Department of Psychology, 1812 Sir Isaac Brock Way, Brock University, St. Catharines, ON L2S 3A1, Canada.
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Repeated Restraint Stress and Binge Alcohol during Adolescence Induce Long-Term Effects on Anxiety-like Behavior and the Expression of the Endocannabinoid System in Male Rats. Biomedicines 2022; 10:biomedicines10030593. [PMID: 35327395 PMCID: PMC8945821 DOI: 10.3390/biomedicines10030593] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 02/25/2022] [Accepted: 03/01/2022] [Indexed: 02/04/2023] Open
Abstract
(1) Background: Negative experiences during adolescence increase the vulnerability to develop mental disorders later in life. A better understanding of the mechanisms underlying these long-term alterations could help to identify better therapeutic interventions. (2) Methods: Adolescent male Wistar rats were used to explore the effects of repeated stress and alcohol exposure on anxiety-like behaviors, plasma corticosterone levels and the gene expression of the endocannabinoid system (ECS) and other relevant signaling systems (glutamatergic, corticotropin-releasing hormone (CRH) and neuropeptide Y (NPY)) in the amygdala and the medial prefrontal cortex (mPFC). (3) Results: Overall, both stress and alcohol induced anxiety-like behaviors, but only the alcohol-exposed rats displayed increased plasma levels of corticosterone. In the amygdala, there was a general deficit in the gene expression of the ECS and increases in the mRNA levels of certain subunits of glutamate receptors. Interestingly, there were significant interaction effects between stress and alcohol on the expression of the NMDA receptor subunits. In addition, increased mRNA levels of the CRH receptor were observed in alcohol-exposed rats. In the mPFC, alcohol exposure was associated with an increase in the gene expression of the ECS. By contrast, the combination of stress and alcohol produced opposite effects. (4) Conclusions: In summary, early stress and alcohol exposure induced long-term anxiety-like behavior in male rats but different mechanisms are involved in these maladaptive changes in the brain.
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Wang H, Huang H, Jiang N, Zhang Y, Lv J, Liu X. Tenuifolin ameliorates chronic restraint stress-induced cognitive impairment in C57BL/6J mice. Phytother Res 2022; 36:1402-1412. [PMID: 35129236 DOI: 10.1002/ptr.7402] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 01/07/2022] [Accepted: 01/15/2022] [Indexed: 12/31/2022]
Abstract
The general consensus is that stress affects the central nervous system and can lead to cognitive problems. The root of Polygala tenuifolia (P. tenuifolia) is a well-known traditional Chinese medicine used for improving brain function. Tenuifolin (TEN) is the major constituent of P. tenuifolia and has a promising neuroprotective property. The purpose of this study was to investigate the alleviating effect of TEN on cognitive impairment induced by chronic restraint stress (CRS) and its mechanism. Our results showed that CRS exposure resulted in impaired cognitive performance in C57BL/6J mice, as indicated by decreased responses in Y-maze, novel objects recognition, and step-through passive avoidance tests. TEN treated daily orally (10 and 20 mg/kg) for 30 days reversed these behavior changes. Meanwhile, TEN could significantly regulate interleukin (IL)-6 and IL-10 levels in the hippocampus. TEN inhibited the toll-like receptor 4/nuclear factor-kappa B-mediated inflammation, as well as adrenocorticotropic hormone and corticosterone levels in serum. Most importantly, we found that TEN also upregulated the expressions of brain-derived neurotrophic factor, tropomyosin kinase B, glucocorticoid receptor, glutamate receptor 1, and synapse-associated proteins. Collectively, these data suggest that TEN has a potential improvement effect on memory loss caused by CRS.
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Affiliation(s)
- Haixia Wang
- The National Clinical Research Center for Mental Disorders & Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China.,Research Center of Pharmacology and Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hong Huang
- Research Center of Pharmacology and Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Ning Jiang
- Research Center of Pharmacology and Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yiwen Zhang
- Research Center of Pharmacology and Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jingwei Lv
- Research Center of Pharmacology and Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xinmin Liu
- Research Center of Pharmacology and Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Effects of Cannabinoid Exposure during Neurodevelopment on Future Effects of Drugs of Abuse: A Preclinical Perspective. Int J Mol Sci 2021; 22:ijms22189989. [PMID: 34576153 PMCID: PMC8472179 DOI: 10.3390/ijms22189989] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/30/2021] [Accepted: 09/09/2021] [Indexed: 12/29/2022] Open
Abstract
The endocannabinoid system plays a central role in the earliest stages of embryonic, postnatal and adolescent neurodevelopment. Aberrant activity of this system at key developmental phases has been shown to affect neural development. The aim of this review is to synthesise and analyse preclinical insights within rodent populations, focusing on the effects that perinatal (embryonic, gestational and early postnatal developmental stages) and adolescent (postnatal day 21–60) cannabinoid exposure impose across time on the subsequent activity of various drugs of abuse. Results in rodents show that exposure to cannabinoids during the perinatal and adolescent period can lead to multifaceted behavioural and molecular changes. In the perinatal period, significant effects of Δ9-THC exposure on subsequent opiate and amphetamine reward-related behaviours were observed primarily in male rodents. These effects were not extended to include cocaine or alcohol. In adolescence, various cannabinoid agonists were used experimentally. This array of cannabinoids demonstrated consistent effects on opioids across sex. In contrast, no significant effects were observed regarding the future activity of amphetamines and cocaine. However, these studies focused primarily on male rodents. In conclusion, numerous gaps and limitations are apparent in the current body of research. The sparsity of studies analysing the perinatal period must be addressed. Future research within both periods must also focus on delineating sex-specific effects, moving away from a male-centric focus. Studies should also aim to utilise more clinically relevant cannabinoid treatments.
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Netzahualcoyotzi C, Rodríguez-Serrano LM, Chávez-Hernández ME, Buenrostro-Jáuregui MH. Early Consumption of Cannabinoids: From Adult Neurogenesis to Behavior. Int J Mol Sci 2021; 22:7450. [PMID: 34299069 PMCID: PMC8306314 DOI: 10.3390/ijms22147450] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/25/2021] [Accepted: 06/26/2021] [Indexed: 01/31/2023] Open
Abstract
The endocannabinoid system (ECS) is a crucial modulatory system in which interest has been increasing, particularly regarding the regulation of behavior and neuroplasticity. The adolescent-young adulthood phase of development comprises a critical period in the maturation of the nervous system and the ECS. Neurogenesis occurs in discrete regions of the adult brain, and this process is linked to the modulation of some behaviors. Since marijuana (cannabis) is the most consumed illegal drug globally and the highest consumption rate is observed during adolescence, it is of particular importance to understand the effects of ECS modulation in these early stages of adulthood. Thus, in this article, we sought to summarize recent evidence demonstrating the role of the ECS and exogenous cannabinoid consumption in the adolescent-young adulthood period; elucidate the effects of exogenous cannabinoid consumption on adult neurogenesis; and describe some essential and adaptive behaviors, such as stress, anxiety, learning, and memory. The data summarized in this work highlight the relevance of maintaining balance in the endocannabinoid modulatory system in the early and adult stages of life. Any ECS disturbance may induce significant modifications in the genesis of new neurons and may consequently modify behavioral outcomes.
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Affiliation(s)
- Citlalli Netzahualcoyotzi
- Laboratorio de Neurociencias, Departamento de Psicología, Universidad Iberoamericana Ciudad de México, Prolongación Paseo de la Reforma 880, Lomas de Santa Fé, Ciudad de México 01219, Mexico; (C.N.); (L.M.R.-S.); (M.E.C.-H.)
- Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Campus Norte, Huixquilucan 52786, Mexico
| | - Luis Miguel Rodríguez-Serrano
- Laboratorio de Neurociencias, Departamento de Psicología, Universidad Iberoamericana Ciudad de México, Prolongación Paseo de la Reforma 880, Lomas de Santa Fé, Ciudad de México 01219, Mexico; (C.N.); (L.M.R.-S.); (M.E.C.-H.)
- Laboratorio de Neurobiología de la alimentación, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla 54090, Mexico
| | - María Elena Chávez-Hernández
- Laboratorio de Neurociencias, Departamento de Psicología, Universidad Iberoamericana Ciudad de México, Prolongación Paseo de la Reforma 880, Lomas de Santa Fé, Ciudad de México 01219, Mexico; (C.N.); (L.M.R.-S.); (M.E.C.-H.)
| | - Mario Humberto Buenrostro-Jáuregui
- Laboratorio de Neurociencias, Departamento de Psicología, Universidad Iberoamericana Ciudad de México, Prolongación Paseo de la Reforma 880, Lomas de Santa Fé, Ciudad de México 01219, Mexico; (C.N.); (L.M.R.-S.); (M.E.C.-H.)
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7
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Sanchez-Marin L, Gavito AL, Decara J, Pastor A, Castilla-Ortega E, Suarez J, de la Torre R, Pavon FJ, Rodriguez de Fonseca F, Serrano A. Impact of intermittent voluntary ethanol consumption during adolescence on the expression of endocannabinoid system and neuroinflammatory mediators. Eur Neuropsychopharmacol 2020; 33:126-138. [PMID: 32057593 DOI: 10.1016/j.euroneuro.2020.01.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 01/09/2020] [Accepted: 01/22/2020] [Indexed: 01/14/2023]
Abstract
The adolescent brain displays high vulnerability to the deleterious effects of ethanol, including greater risk of developing alcohol use disorder later in life. Here, we characterized the gene expression of the endocannabinoid system (ECS) and relevant signaling systems associated with neuroinflammation and emotional behaviors in the brain of young adult control and ethanol-exposed (EtOH) rats. We measured mRNA levels of candidate genes using quantitative real time PCR in the medial prefrontal cortex (mPFC), amygdala and hippocampus. EtOH rats were generated by maintenance on an intermittent and voluntary ethanol consumption during adolescence using the two-bottle choice paradigm (4 days/week for 4 weeks) followed by 2 week-withdrawal, a time-point of withdrawal with no physical symptoms. Mean differences and effect sizes were calculated using t-test and Cohen's d values. In the mPFC and hippocampus, EtOH rats had significantly higher mRNA expression of endocannabinoid-signaling (mPFC: Ppara, Dagla, Daglb and Napepld; and hippocampus: Cnr2, Dagla and Mgll) and neuroinflammation-associated genes (mPFC: Gfap; and hippocampus: Aif1) than in controls. Moreover, EtOH rats had significantly higher mRNA expression of neuropeptide Y receptor genes (Npy1r, Npy2r and Npy5r) in the hippocampus. Finally, EtOH rats also displayed higher plasma endocannabinoid levels than controls. In conclusion, these results suggest that adolescent ethanol exposure can lead to long-term alterations in the gene expression of the ECS and other signaling systems involved in neuroinflammation and regulation of emotional behaviors in key brain areas for the development of addiction.
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Affiliation(s)
- L Sanchez-Marin
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga, Universidad de Málaga, Avda. Carlos Haya 82, Sótano, Málaga 29010, Spain
| | - A L Gavito
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga, Universidad de Málaga, Avda. Carlos Haya 82, Sótano, Málaga 29010, Spain
| | - J Decara
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga, Universidad de Málaga, Avda. Carlos Haya 82, Sótano, Málaga 29010, Spain
| | - A Pastor
- Programa de Neurociencias, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - E Castilla-Ortega
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga, Universidad de Málaga, Avda. Carlos Haya 82, Sótano, Málaga 29010, Spain
| | - J Suarez
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga, Universidad de Málaga, Avda. Carlos Haya 82, Sótano, Málaga 29010, Spain
| | - R de la Torre
- Programa de Neurociencias, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - F J Pavon
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga, Universidad de Málaga, Avda. Carlos Haya 82, Sótano, Málaga 29010, Spain; Unidad Gestión Clínica del Corazón, IBIMA, Hospital Universitario Virgen de la Victoria, Universidad de Málaga, Málaga, Spain
| | - F Rodriguez de Fonseca
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga, Universidad de Málaga, Avda. Carlos Haya 82, Sótano, Málaga 29010, Spain.
| | - A Serrano
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga, Universidad de Málaga, Avda. Carlos Haya 82, Sótano, Málaga 29010, Spain.
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Tirado-Muñoz J, Lopez-Rodriguez AB, Fonseca F, Farré M, Torrens M, Viveros MP. Effects of cannabis exposure in the prenatal and adolescent periods: Preclinical and clinical studies in both sexes. Front Neuroendocrinol 2020; 57:100841. [PMID: 32339546 DOI: 10.1016/j.yfrne.2020.100841] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 03/15/2020] [Accepted: 04/19/2020] [Indexed: 10/24/2022]
Abstract
Cannabis is the most commonly used illicit drug among adolescents and young adults, including pregnant women. There is substantial evidence for a significant association between prenatal cannabis exposure and lower birth weight in offspring, and mixed results regarding later behavioural outcomes in the offspring. Adolescent cannabis use, especially heavy use, has been associated with altered executive function, depression, psychosis and use of other drugs later in life. Human studies have limitations due to several confounding factors and have provided scarce information about sex differences. In general, animal studies support behavioural alterations reported in humans and have revealed diverse sex differences and potential underlying mechanisms (altered mesolimbic dopaminergic and hippocampal glutamatergic systems and interference with prefrontal cortex maturation). More studies are needed that analyse sex and gender influences on cannabis-induced effects with great clinical relevance such as psychosis, cannabis use disorder and associated comorbidities, to achieve more personalized and accurate treatments.
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Affiliation(s)
- Judith Tirado-Muñoz
- Addiction Research Group, IMIM-Institut Hospital del Mar d'Investigacions Mèdiques, Barcelona, Spain
| | - Ana Belen Lopez-Rodriguez
- School of Biochemistry & Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Francina Fonseca
- Addiction Research Group, IMIM-Institut Hospital del Mar d'Investigacions Mèdiques, Barcelona, Spain; Institute of Neuropsychiatry and Addictions, Parc de Salut Mar, Barcelona, Spain; Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Magi Farré
- Clinical Pharmacology Unit, Hospital Universitari Germans Trias i Pujol and Institut de Recerca Germas Trias (HUGTP-IGTP), Badalona, Spain; Department of Pharmacology, Therapeutics and Toxicology, Universitat Autònoma de Barcelona (UAB), Barcelona, Spain
| | - Marta Torrens
- Addiction Research Group, IMIM-Institut Hospital del Mar d'Investigacions Mèdiques, Barcelona, Spain; Institute of Neuropsychiatry and Addictions, Parc de Salut Mar, Barcelona, Spain; Universitat Autònoma de Barcelona, Barcelona, Spain
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Disrupting the endocannabinoid system in early adolescence negatively impacts sociability. Pharmacol Biochem Behav 2019; 188:172832. [PMID: 31778723 DOI: 10.1016/j.pbb.2019.172832] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 11/22/2019] [Accepted: 11/22/2019] [Indexed: 01/23/2023]
Abstract
Animal models suggest that the endocannabinoid system (eCS) helps regulate various aspects of social behavior, including play behavior and social reward, during adolescence. Properly tuned endocannabinoid signaling may be a critical developmental component in the emergence of normal adult sociability. In the current experiment, we attempted to pharmacologically disrupt endocannabinoid tone during early adolescence, and then measure the behavioral effects at two subsequent time points. 36 male and 36 female Long Evans rats received daily injections of one of three treatments between post-natal day (PND) 25-39: 1) vehicle treatment, 2) 0.4 mg/kg CP55,940 (a potent CB1/CB2 receptor agonist), or 3) 0.5 mg/kg AM251 (a CB1 receptor antagonist/inverse agonist). Both soon after treatment (PND 40-44) and several weeks later (PND 66-70), subjects were tested in an elevated plus maze (EPM) for anxiety and in a three-chambered apparatus for sociability. For the latter test, the number of entries into each chamber and the amount of time spent investigating each target were measured. Analyses revealed significant main effects of both sex and age on sociability: males expressed greater sociability compared to females, and sociability was higher in adolescence than adulthood. Most importantly, drug treatment (both CP55,940 and AM251) attenuated sociability in adolescence without having a significant effect on anxiety in the EPM. However, this effect did not persist into adulthood. These results indicate that pharmacological disruption of endocannabinoid tone - through either chronic agonism or antagonism of cannabinoid receptors - during early adolescence has a detrimental effect on sociability. This effect may be caused by transient, compensatory alterations in the eCS.
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Richter-Levin G, Stork O, Schmidt MV. Animal models of PTSD: a challenge to be met. Mol Psychiatry 2019; 24:1135-1156. [PMID: 30816289 PMCID: PMC6756084 DOI: 10.1038/s41380-018-0272-5] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Revised: 08/13/2018] [Accepted: 09/11/2018] [Indexed: 02/07/2023]
Abstract
Recent years have seen increased interest in psychopathologies related to trauma exposure. Specifically, there has been a growing awareness to posttraumatic stress disorder (PTSD) in part due to terrorism, climate change-associated natural disasters, the global refugee crisis, and increased violence in overpopulated urban areas. However, notwithstanding the increased awareness to the disorder, the increasing number of patients, and the devastating impact on the lives of patients and their families, the efficacy of available treatments remains limited and highly unsatisfactory. A major scientific effort is therefore devoted to unravel the neural mechanisms underlying PTSD with the aim of paving the way to developing novel or improved treatment approaches and drugs to treat PTSD. One of the major scientific tools used to gain insight into understanding physiological and neuronal mechanisms underlying diseases and for treatment development is the use of animal models of human diseases. While much progress has been made using these models in understanding mechanisms of conditioned fear and fear memory, the gained knowledge has not yet led to better treatment options for PTSD patients. This poor translational outcome has already led some scientists and pharmaceutical companies, who do not in general hold opinions against animal models, to propose that those models should be abandoned. Here, we critically examine aspects of animal models of PTSD that may have contributed to the relative lack of translatability, including the focus on the exposure to trauma, overlooking individual and sex differences, and the contribution of risk factors. Based on findings from recent years, we propose research-based modifications that we believe are required in order to overcome some of the shortcomings of previous practice. These modifications include the usage of animal models of PTSD which incorporate risk factors and of the behavioral profiling analysis of individuals in a sample. These modifications are aimed to address factors such as individual predisposition and resilience, thus taking into consideration the fact that only a fraction of individuals exposed to trauma develop PTSD. We suggest that with an appropriate shift of practice, animal models are not only a valuable tool to enhance our understanding of fear and memory processes, but could serve as effective platforms for understanding PTSD, for PTSD drug development and drug testing.
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Affiliation(s)
- Gal Richter-Levin
- Sagol Department of Neurobiology, University of Haifa, Haifa, Israel. .,The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, Haifa, Israel. .,Psychology Department, University of Haifa, Haifa, Israel.
| | - Oliver Stork
- 0000 0001 1018 4307grid.5807.aDepartment of Genetics & Molecular Neurobiology, Institute of Biology, Otto-von-Guericke-University Magdeburg, Leipziger Str. 44, 39120 Magdeburg, Germany ,grid.452320.2Center for Behavioral Brain Sciences, Universitätsplatz 2, 39106 Magdeburg, Germany
| | - Mathias V. Schmidt
- 0000 0000 9497 5095grid.419548.5Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
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11
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Simone JJ, Baumbach JL, McCormick CM. Sex-specific effects of CB1 receptor antagonism and stress in adolescence on anxiety, corticosterone concentrations, and contextual fear in adulthood in rats. Int J Dev Neurosci 2018; 69:119-131. [PMID: 30063953 DOI: 10.1016/j.ijdevneu.2018.07.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 07/23/2018] [Accepted: 07/26/2018] [Indexed: 02/07/2023] Open
Abstract
There is a paucity of research regarding the role of endogenous cannabinoid signalling in adolescence on brain and behaviour development. We previously demonstrated effects of repeated CB1 receptor antagonism in adolescence on socioemotional behaviours and neural protein expression 24-48 h after the last drug administration in female rats, with no effect in males. Here we investigate whether greater effects would be manifested after a lengthier delay. In Experiment 1, male and female rats were administered either 1 mg / kg of the CB1 receptor-selective antagonist AM251, vehicle (VEH), or did not receive injections (NoINJ) daily on postnatal days (PND) 30-44 either alone (no adolescent confinement stress; noACS), or in tandem with 1 h ACS. On PND 70, adolescent AM251 exposure reduced anxiety in an elevated plus maze in males, irrespective of ACS, with no effects in females. On PND 73, there were no group differences in either sex in plasma corticosterone concentrations before or after 30 min of restraint stress, although injection stress resulted in higher baseline concentrations in males. Brains were collected on PND 74, with negligible effects of either AM251 or ACS on protein markers of synaptic plasticity and of the endocannabinoid system in the hippocampus and medial prefrontal cortex. In Experiment 2, rats from both sexes were treated with vehicle or AM251 on PND 30-44 and were tested for contextual fear conditioning and extinction in adulthood. AM251 females had greater fear recall than VEH females 24 h after conditioning, with no group differences in within- or between-session fear extinction. There were no group differences in long-term extinction memory, although AM251 females froze more during a reconditioning trial compared with VEH females. There were no group differences on any of the fear conditioning measures in males. Together, these findings indicate a modest, sex-specific role of CB1 receptor signalling in adolescence on anxiety-like behaviour in males and conditioned fear behaviour in females.
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Affiliation(s)
- Jonathan J Simone
- Department of Biological Sciences, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario, L2S 3A1, Canada.
| | - Jennet L Baumbach
- Department of Psychology, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario, L2S 3A1, Canada.
| | - Cheryl M McCormick
- Department of Biological Sciences, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario, L2S 3A1, Canada; Department of Psychology, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario, L2S 3A1, Canada; Center for Neuroscience, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario, L2S 3A1, Canada.
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12
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Palmitoylation as a Functional Regulator of Neurotransmitter Receptors. Neural Plast 2018; 2018:5701348. [PMID: 29849559 PMCID: PMC5903346 DOI: 10.1155/2018/5701348] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 01/29/2018] [Indexed: 12/11/2022] Open
Abstract
The majority of neuronal proteins involved in cellular signaling undergo different posttranslational modifications significantly affecting their functions. One of these modifications is a covalent attachment of a 16-C palmitic acid to one or more cysteine residues (S-palmitoylation) within the target protein. Palmitoylation is a reversible modification, and repeated cycles of palmitoylation/depalmitoylation might be critically involved in the regulation of multiple signaling processes. Palmitoylation also represents a common posttranslational modification of the neurotransmitter receptors, including G protein-coupled receptors (GPCRs) and ligand-gated ion channels (LICs). From the functional point of view, palmitoylation affects a wide span of neurotransmitter receptors activities including their trafficking, sorting, stability, residence lifetime at the cell surface, endocytosis, recycling, and synaptic clustering. This review summarizes the current knowledge on the palmitoylation of neurotransmitter receptors and its role in the regulation of receptors functions as well as in the control of different kinds of physiological and pathological behavior.
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Meyer HC, Lee FS, Gee DG. The Role of the Endocannabinoid System and Genetic Variation in Adolescent Brain Development. Neuropsychopharmacology 2018; 43:21-33. [PMID: 28685756 PMCID: PMC5719094 DOI: 10.1038/npp.2017.143] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Revised: 05/17/2017] [Accepted: 06/23/2017] [Indexed: 12/19/2022]
Abstract
During adolescence, both rodent and human studies have revealed dynamic changes in the developmental trajectories of corticolimbic structures, which are known to contribute to the regulation of fear and anxiety-related behaviors. The endocannabinoid (eCB) system critically regulates stress responsivity and anxiety throughout the life span. Emerging evidence suggests that during adolescence, changes in eCB signaling contribute to the maturation of local and corticolimbic circuit populations of neurons, such as mediating the balance between excitatory and inhibitory neurotransmission within the prefrontal cortex. This function of the eCB system facilitates efficient communication within and between brain regions and serves a central role in establishing complex and adaptive cognitive and behavioral processing. Although these peri-adolescent changes in eCB signaling promote brain development and plasticity, they also render this period a particularly sensitive one for environmental perturbations to these normative fluctuations in eCB signaling, such as stress, potentially leading to altered developmental trajectories of neural circuits governing emotional behaviors. In this review, we focus on the role of eCB signaling on the regulation of stress and anxiety-related behaviors both during and after adolescence. Moreover, we discuss the functional implications of human genetic variation in the eCB system for the risk for anxiety and consequences of stress across development and into adulthood.
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Affiliation(s)
- Heidi C Meyer
- Department of Psychiatry, Weill Cornell Medical College, New York, NY, USA
| | - Francis S Lee
- Department of Psychiatry, Weill Cornell Medical College, New York, NY, USA
- Sackler Institute for Developmental Psychobiology, Weill Cornell Medical College, New York, NY, USA
| | - Dylan G Gee
- Department of Psychology, Yale University, New Haven, CT, USA
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Simone JJ, Baumbach JL, McCormick CM. Effects of CB1 receptor antagonism and stress exposures in adolescence on socioemotional behaviours, neuroendocrine stress responses, and expression of relevant proteins in the hippocampus and prefrontal cortex in rats. Neuropharmacology 2017; 128:433-447. [PMID: 29092785 DOI: 10.1016/j.neuropharm.2017.10.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 10/12/2017] [Accepted: 10/23/2017] [Indexed: 01/07/2023]
Abstract
Little is known about the consequences of altered endocannabinoid signalling in adolescence. We hypothesized that CB1 receptor antagonism (AM251, 1 mg/kg) and stress exposures (1 h confinement stress) in adolescence (daily, postnatal days 30-44) would interact to increase neuroendocrine stress responses and anxiety when investigated a minimum of 24 h after drug and stress treatments; these treatment effects were independent of each other. Changes in homecage behaviour and in weight gain confirmed that both males and females were sensitive to the treatments. Nevertheless, in males, repeated AM251 administration was without effect on any of the measures investigated in days post-treatment. Males had reduced corticosterone release to the repeated stress and had increased GAD67 expression in the ventral hippocampus under baseline conditions. In females, AM251 also reduced weight gain and increased stereotypic behaviours in the homecage; these same females showed increased sociality, reduced CB1 receptor expression in the dorsal hippocampus, and increased GAD67 expression in the prefrontal cortex. Further, females exposed to repeated stress had enhanced recovery to baseline corticosterone concentrations after stress. The inclusion of a non-injected comparison group also revealed stress of injection effects in both sexes that otherwise would have been masked. Together, the findings demonstrate effects of CB1 receptor antagonism and stress that were more evident in females than males, suggesting that females may be more vulnerable to the consequences of disrupted endocannabinoid signalling during adolescence.
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Affiliation(s)
- Jonathan J Simone
- Department of Biological Sciences, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada
| | - Jennet L Baumbach
- Department of Psychology, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada
| | - Cheryl M McCormick
- Department of Biological Sciences, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada; Department of Psychology, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada; Centre for Neuroscience, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada.
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Chronic CB1 cannabinoid receptor antagonism persistently increases dendritic spine densities in brain regions important to zebra finch vocal learning and production in an antidepressant-sensitive manner. Brain Res 2017; 1672:1-9. [PMID: 28743448 DOI: 10.1016/j.brainres.2017.07.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 07/14/2017] [Accepted: 07/19/2017] [Indexed: 01/22/2023]
Abstract
During typical late-postnatal CNS development, net reductions in dendritic spine densities are associated with activity-dependent learning. Prior results showed agonist exposure in young animals increased spine densities in a subset of song regions while adult exposures did not, suggesting endocannabinoid signaling regulates dendritic spine dynamics important to vocal development. Here we addressed this question using the CB1 receptor-selective antagonist SR141716A (SR) to disrupt endocannabinoid signaling both during and after vocal learning. We hypothesized antagonist exposure during vocal development, but not adulthood, would alter spine densities. Following 25days of exposure and a 25day maturation period, 3D reconstructions of Golgi-Cox stained neurons were used to measure spine densities. We found antagonist treatments during both age periods increased densities within Area X (basal ganglia) and following adult treatments within HVC (premotor cortical-like). Results suggest both inappropriate cannabinoid receptor stimulation and inhibition are capable of similar disregulatory effects during establishment of circuits important to vocal learning, with antagonism extending these effects through adulthood. Given clinical evidence of depressant effects of SR, we tested the ability of the antidepressant monoamine oxidase inhibitor (MAOI) phenelzine to mitigate SR-induced spine density increases. This was confirmed implicating interaction between monoamine and endocannabinoid systems. Finally, we evaluated acute effects of these drugs to alter ability of novel song exposure to increase spine densities in auditory NCM and other regions, finding when combined, SR and phenelzine increased densities within Area X. These results contribute to understanding relevance of dendritic spine dynamics in neuronal development, drug abuse, and depression.
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Perescis MFJ, de Bruin N, Heijink L, Kruse C, Vinogradova L, Lüttjohann A, van Luijtelaar G, van Rijn CM. Cannabinoid antagonist SLV326 induces convulsive seizures and changes in the interictal EEG in rats. PLoS One 2017; 12:e0165363. [PMID: 28151935 PMCID: PMC5289424 DOI: 10.1371/journal.pone.0165363] [Citation(s) in RCA: 7] [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: 06/27/2016] [Accepted: 10/11/2016] [Indexed: 11/18/2022] Open
Abstract
Cannabinoid CB1 antagonists have been investigated for possible treatment of e.g. obesity-related disorders. However, clinical application was halted due to their symptoms of anxiety and depression. In addition to these adverse effects, we have shown earlier that chronic treatment with the CB1 antagonist rimonabant may induce EEG-confirmed convulsive seizures. In a regulatory repeat-dose toxicity study violent episodes of “muscle spasms” were observed in Wistar rats, daily dosed with the CB1 receptor antagonist SLV326 during 5 months. The aim of the present follow-up study was to investigate whether these violent movements were of an epileptic origin. In selected SLV326-treated and control animals, EEG and behavior were monitored for 24 hours. 25% of SLV326 treated animals showed 1 to 21 EEG-confirmed generalized convulsive seizures, whereas controls were seizure-free. The behavioral seizures were typical for a limbic origin. Moreover, interictal spikes were found in 38% of treated animals. The frequency spectrum of the interictal EEG of the treated rats showed a lower theta peak frequency, as well as lower gamma power compared to the controls. These frequency changes were state-dependent: they were only found during high locomotor activity. It is concluded that long term blockade of the endogenous cannabinoid system can provoke limbic seizures in otherwise healthy rats. Additionally, SLV326 alters the frequency spectrum of the EEG when rats are highly active, suggesting effects on complex behavior and cognition.
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Affiliation(s)
- Martin F. J. Perescis
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
- HAS University of Applied Sciences, ‘s-Hertogenbosch, The Netherlands
- * E-mail:
| | - Natasja de Bruin
- Abbott Healthcare Products BV (formerly Solvay Pharmaceuticals), Weesp, The Netherlands
| | - Liesbeth Heijink
- Abbott Healthcare Products BV (formerly Solvay Pharmaceuticals), Weesp, The Netherlands
| | - Chris Kruse
- Abbott Healthcare Products BV (formerly Solvay Pharmaceuticals), Weesp, The Netherlands
| | - Lyudmila Vinogradova
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
| | - Annika Lüttjohann
- Institut für Physiologie I, Westfälische Wilhelms Universität Münster, Münster, Germany
| | - Gilles van Luijtelaar
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Clementina M. van Rijn
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
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Morena M, Leitl KD, Vecchiarelli HA, Gray JM, Campolongo P, Hill MN. Emotional arousal state influences the ability of amygdalar endocannabinoid signaling to modulate anxiety. Neuropharmacology 2016; 111:59-69. [DOI: 10.1016/j.neuropharm.2016.08.020] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/26/2016] [Accepted: 08/16/2016] [Indexed: 01/04/2023]
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Lee TTY, Hill MN, Lee FS. Developmental regulation of fear learning and anxiety behavior by endocannabinoids. GENES, BRAIN, AND BEHAVIOR 2016; 15:108-24. [PMID: 26419643 PMCID: PMC4713313 DOI: 10.1111/gbb.12253] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 09/03/2015] [Accepted: 09/14/2015] [Indexed: 12/31/2022]
Abstract
The developing brain undergoes substantial maturation into adulthood and the development of specific neural structures occurs on differing timelines. Transient imbalances between developmental trajectories of corticolimbic structures, which are known to contribute to regulation over fear learning and anxiety, can leave an individual susceptible to mental illness, particularly anxiety disorders. There is a substantial body of literature indicating that the endocannabinoid (eCB) system critically regulates stress responsivity and emotional behavior throughout the life span, making this system a novel therapeutic target for stress- and anxiety-related disorders. During early life and adolescence, corticolimbic eCB signaling changes dynamically and coincides with different sensitive periods of fear learning, suggesting that eCB signaling underlies age-specific fear learning responses. Moreover, perturbations to these normative fluctuations in corticolimbic eCB signaling, such as stress or cannabinoid exposure, could serve as a neural substrate contributing to alterations to the normative developmental trajectory of neural structures governing emotional behavior and fear learning. In this review, we first introduce the components of the eCB system and discuss clinical and rodent models showing eCB regulation of fear learning and anxiety in adulthood. Next, we highlight distinct fear learning and regulation profiles throughout development and discuss the ontogeny of the eCB system in the central nervous system, and models of pharmacological augmentation of eCB signaling during development in the context of fear learning and anxiety.
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Affiliation(s)
- Tiffany T.-Y. Lee
- Dept. of Psychology, University of British Columbia, Vancouver, Canada, V6T 1Z4
| | - Matthew N. Hill
- Hotchkiss Brain Institute and Mathison Center for Mental Health Research and Education, Departments of Cell Biology and Anatomy & Psychiatry, University of Calgary, Calgary AB, Canada T2N4N1
| | - Francis S. Lee
- Department of Psychiatry, Weill Cornell Medical College of Cornell University, 1300 York Avenue, New York, New York 10065, USA
- Department of Pharmacology, Weill Cornell Medical College of Cornell University, 1300 York Avenue, New York, New York 10065, USA
- Sackler Institute for Developmental Psychobiology, Weill Cornell Medical College of Cornell University, 1300 York Avenue, New York, New York 10065, USA
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Lee TTY, Gorzalka BB. Evidence for a Role of Adolescent Endocannabinoid Signaling in Regulating HPA Axis Stress Responsivity and Emotional Behavior Development. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2015; 125:49-84. [PMID: 26638764 DOI: 10.1016/bs.irn.2015.09.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Adolescence is a period characterized by many distinct physical, behavioral, and neural changes during the transition from child- to adulthood. In particular, adolescent neural changes often confer greater plasticity and flexibility, yet with this comes the potential for heightened vulnerability to external perturbations such as stress exposure or recreational drug use. There is substantial evidence to suggest that factors such as adolescent stress exposure have longer lasting and sometimes more deleterious effects on an organism than stress exposure during adulthood. Moreover, the adolescent neuroendocrine response to stress exposure is different from that of adults, suggesting that further maturation of the adolescent hypothalamic-pituitary-adrenal (HPA) axis is required. The endocannabinoid (eCB) system is a potential candidate underlying these age-dependent differences given that it is an important regulator of the adult HPA axis and neuronal development. Therefore, this review will focus on (1) the functionality of the adolescent HPA axis, (2) eCB regulation of the adult HPA axis, (3) dynamic changes in eCB signaling during the adolescent period, (4) the effects of adolescent stress exposure on the eCB system, and (5) modulation of HPA axis activity and emotional behavior by adolescent cannabinoid treatment. Collectively, the emerging picture suggests that the eCB system mediates interactions between HPA axis stress responsivity, emotionality, and maturational stage. These findings may be particularly relevant to our understanding of the development of affective disorders and the risks of adolescent cannabis consumption on emotional health and stress responsivity.
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Affiliation(s)
- Tiffany T-Y Lee
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Boris B Gorzalka
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada.
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