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Clay JM, Badariotti JI, Kozhushko N, Parker MO. HPA activity mediates the link between trait impulsivity and boredom. Physiol Behav 2024; 284:114637. [PMID: 38997097 DOI: 10.1016/j.physbeh.2024.114637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 07/03/2024] [Accepted: 07/09/2024] [Indexed: 07/14/2024]
Abstract
Boredom, a complex emotional state with implications for mental health and well-being, has garnered attention across disciplines, yet remains relatively understudied in psychiatric research. Here, we explored the intricate relationship between trait-impulsivity, stress, and boredom across two studies. Participants completed self-report measures of trait-impulsivity and boredom and boredom-inducing tasks. Study 1, involving 80 participants (42 women and 38 men, aged 20-63), replicates previous findings, by demonstrating that impulsive individuals report greater boredom following a boring task. Study 2 then extends this, using 20 participants (9 women and 12 men, aged 18-24), to show that hypothalamic-pituitary-adrenal (HPA) axis activity, specifically heightened salivary cortisol responses, mediate the link between impulsivity and boredom following a boring task. Collectively, these results demonstrate that HPA axis activity may underline the relationship between trait-impulsivity and boredom by extending previous work and offering a novel insight into potential mechanisms. These findings offer promise for personalised interventions, designed for high impulsivity individuals, to alleviate the negative impacts of boredom and potentially break the identified feedback loop.
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Affiliation(s)
- James M Clay
- Department of Psychology, University of Portsmouth, UK; Canadian Institute for Substance Use Research, University of Victoria, Victoria, Canada; Department of Community Health and Epidemiology, Dalhousie University, Halifax, Canada
| | | | - Nikita Kozhushko
- School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, UK
| | - Matthew O Parker
- Surrey Sleep Research Centre, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK.
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2
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Govindula A, Ranadive N, Nampoothiri M, Rao CM, Arora D, Mudgal J. Emphasizing the Crosstalk Between Inflammatory and Neural Signaling in Post-traumatic Stress Disorder (PTSD). J Neuroimmune Pharmacol 2023; 18:248-266. [PMID: 37097603 PMCID: PMC10577110 DOI: 10.1007/s11481-023-10064-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 04/16/2023] [Indexed: 04/26/2023]
Abstract
Post-traumatic stress disorder (PTSD) is a chronic incapacitating condition with recurrent experience of trauma-related memories, negative mood, altered cognition, and hypervigilance. Agglomeration of preclinical and clinical evidence in recent years specified that alterations in neural networks favor certain characteristics of PTSD. Besides the disruption of hypothalamus-pituitary-axis (HPA) axis, intensified immune status with elevated pro-inflammatory cytokines and arachidonic metabolites of COX-2 such as PGE2 creates a putative scenario in worsening the neurobehavioral facet of PTSD. This review aims to link the Diagnostic and Statistical Manual of mental disorders (DSM-V) symptomology to major neural mechanisms that are supposed to underpin the transition from acute stress reactions to the development of PTSD. Also, to demonstrate how these intertwined processes can be applied to probable early intervention strategies followed by a description of the evidence supporting the proposed mechanisms. Hence in this review, several neural network mechanisms were postulated concerning the HPA axis, COX-2, PGE2, NLRP3, and sirtuins to unravel possible complex neuroinflammatory mechanisms that are obscured in PTSD condition.
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Affiliation(s)
- Anusha Govindula
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Niraja Ranadive
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Madhavan Nampoothiri
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - C Mallikarjuna Rao
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Devinder Arora
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India.
- School of Pharmacy and Medical Sciences, Griffith University, Gold Coast campus, Gold Coast, Queensland, 4222, Australia.
| | - Jayesh Mudgal
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India.
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3
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Sarkar I, Snippe-Strauss M, Tenenhaus Zamir A, Benhos A, Richter-Levin G. Individual behavioral profiling as a translational approach to assess treatment efficacy in an animal model of post-traumatic stress disorder. Front Neurosci 2022; 16:1071482. [PMID: 36620437 PMCID: PMC9815535 DOI: 10.3389/fnins.2022.1071482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 11/25/2022] [Indexed: 12/24/2022] Open
Abstract
A major challenge in treating post-traumatic stress disorder (PTSD) continues to be the large variability in responsiveness to pharmacotherapy. Only 20-30% of patients experience total remission to a specific treatment, while others demonstrate either partial remission or no response. However, this heterogeneity in response to pharmacotherapy has not been adequately addressed in animal models, since these analyze the averaged group effects, ignoring the individual variability to treatment response, which seriously compromises the translation power of such models. Here we examined the possibility of employing an "individual behavioral profiling" approach, originally developed to differentiate between "affected" and "exposed-unaffected" individuals in an animal model of PTSD, to also enable dissociating "responders" or "non-responders" after SSRI (fluoxetine) treatment. Importantly, this approach does not rely on a group averaged response to a single behavioral parameter, but considers a cluster of behavioral parameters, to individually characterize an animal as either "responder" or "non-responder" to the treatment. The main variable to assess drug efficacy thus being the proportion of "responders" following treatment. Alteration in excitatory/inhibitory (E/I) balance has been proposed as being associated with stress-related psychopathology. Toward a functional proof of concept for our behaviorally-based characterization approach, we examined the expression patterns of α1 and α2 subunits of GABAA receptor, and GluN1 and GluN2A subunits of the NMDAR receptor in the ventral hippocampus, as well as electrophysiologically local circuit activity in the dorsal dentate gyrus (DG). We demonstrate that with both parameters, treatment "responders" differed from treatment "non-responders," confirming the functional validity of the behavior-based categorization. The results suggest that the ability to respond to fluoxetine treatment may be linked to the ability to modulate excitation-inhibition balance in the hippocampus. We propose that employing the "individual behavioral profiling" approach, and the resultant novel variable of the proportion of "recovered" individuals following treatment, offers an effective translational tool to assess pharmacotherapy treatment efficacy in animal models of stress and trauma-related psychopathology.
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Affiliation(s)
- Ishita Sarkar
- Sagol Department of Neurobiology, University of Haifa, Haifa, Israel
| | | | | | - Amir Benhos
- School of Psychological Sciences, University of Haifa, Haifa, Israel
| | - Gal Richter-Levin
- Sagol Department of Neurobiology, University of Haifa, Haifa, Israel,School of Psychological Sciences, University of Haifa, Haifa, Israel,The Integrated Brain and Behavior Research Center, University of Haifa, Haifa, Israel,*Correspondence: Gal Richter-Levin,
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4
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Liang J, Wang H, Zeng Y, Qu Y, Liu Q, Zhao F, Duan J, Jiang Y, Li S, Ying J, Li J, Mu D. Physical exercise promotes brain remodeling by regulating epigenetics, neuroplasticity and neurotrophins. Rev Neurosci 2021; 32:615-629. [PMID: 33583156 DOI: 10.1515/revneuro-2020-0099] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 10/26/2020] [Indexed: 02/05/2023]
Abstract
Exercise has been shown to have beneficial effects on brain functions in humans and animals. Exercise can improve memory and learning in age-related neurodegenerative diseases. In animal models, physical exercise regulates epigenetics, promotes synaptic plasticity and hippocampal neurogenesis, regulates the expression levels of neurotrophic factors, and improves cognitive function. Therefore, exercise is very important for brain rehabilitation and remodeling. The purpose of this review is to explore the mechanisms by which exercise exerts positive effects on brain function. This knowledge implies that physical exercise can be used as a non-drug therapy for neurological diseases.
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Affiliation(s)
- Juan Liang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
| | - Huiqing Wang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
| | - Yan Zeng
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
| | - Yi Qu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
| | - Qian Liu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
| | - Fengyan Zhao
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
| | - Jianan Duan
- West China Hospital, Sichuan University, Chengdu610041, China
| | - Yin Jiang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
| | - Shiping Li
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
| | - Junjie Ying
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
| | - Jinhui Li
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
| | - Dezhi Mu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu610041, China
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5
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Characterization of Comorbid Posttraumatic Stress Disorder and Major Depressive Disorder Using Ketamine as an Experimental Medicine Probe. JOURNAL OF PSYCHIATRY AND BRAIN SCIENCE 2021; 6. [PMID: 34632081 PMCID: PMC8500463 DOI: 10.20900/jpbs.20210012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Comorbid posttraumatic stress disorder and major depressive disorder (PTSD + MDD) is the most common pathological response to trauma, yet despite their synergistic detriment to health, knowledge regarding the neurobiological mechanism underlying PTSD + MDD is extremely limited. This study proposes a novel model of PTSD + MDD that is built on biological systems shown to underlay PTSD + MDD and takes advantage of ketamine’s unique suitability to probe PTSD + MDD due to its rescue of stress-related neuroplasticity deficits. The central hypothesis is that changes in PTSD + MDD clinical symptoms are associated with functional connectivity changes and cognitive dysfunction and that ketamine infusions improve clinical symptoms by correction of functional connectivity changes and improvement in cognition. Participants with PTSD + MDD (n = 42) will be randomized to receive a series of six ketamine infusions or saline-placebo over three weeks. Pre/post-measures will include: (1) neuroimaging; (2) cognitive functioning task performance; and (3) PTSD, MDD, and rumination self-report measures. These measures will also be collected once in a trauma-exposed group including PTSD-only (n = 10), trauma-exposed-MDD (TE-MDD; n = 10), and healthy controls (HC, n = 21). Successful completion of the study will strongly support the concept of a biologically-based model of PTSD + MDD. The results will (1) identify functional imaging signatures of the mechanisms underpinning pathological responses to trauma, (2) shift focus from mono-diagnostic silos to unified biological and behavioral disease processes and, thus, (3) inform interventions to correct dysregulation of PTSD + MDD symptom clusters thereby supporting more precise treatments and better outcomes.
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Persike DS, Al-Kass SY. Challenges of post-traumatic stress disorder (PTSD) in Iraq: biochemical network and methodologies. A brief review. Horm Mol Biol Clin Investig 2020; 41:/j/hmbci.ahead-of-print/hmbci-2020-0037/hmbci-2020-0037.xml. [PMID: 33155990 DOI: 10.1515/hmbci-2020-0037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 09/10/2020] [Indexed: 11/15/2022]
Abstract
Post-traumatic stress disorder (PTSD) is a multifaceted syndrome due to its complex pathophysiology. Signals of illness include alterations in genes, proteins, cells, tissues, and organism-level physiological modifications. Specificity of sensitivity to PTSD suggests that response to trauma depend on gender and type of adverse event being experienced. Individuals diagnosed with PTSD represent a heterogeneous group, as evidenced by differences in symptoms, course, and response to treatment. It is clear that the biochemical mechanisms involved in PTSD need to be elucidated to identify specific biomarkers. A brief review of the recent literature in Pubmed was made to explore the major biochemical mechanisms involved in PTSD and the methodologies applied in the assessment of the disease. PTSD shows pre-exposure vulnerability factors in addition to trauma-induced alterations. The disease was found to be associated with dysfunctions of the hypothalamic-pituitary-adrenal axis (HPA) and hypothalamus-pituitary-thyroid axis. Sympathetic nervous system (SNS) activity play a role in PTSD by releasing norepinephrine and epinephrine. Cortisol release from the adrenal cortex amplifies the SNS response. Cortisol levels in PTSD patients, especially women, are later reduced by a negative feedback mechanism which contributes to neuroendocrine alterations and promotes structural changes in the brain leading to PTSD. Gender differences in normal HPA responsiveness may be due to an increased vulnerability in women to PTSD. Serotonin and dopamine levels were found to be abnormal in the presence of PTSD. Mechanisms such as the induction of neuroinflammation and alterations of mitochondrial energy processing were also associated with PTSD.
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Affiliation(s)
- Daniele Suzete Persike
- Department of Medicinal Chemistry, College of Pharmacy, University of Dohuk, Kurdistan Region, Iraq
| | - Suad Yousif Al-Kass
- Department of Medicinal Chemistry, College of Pharmacy, University of Dohuk, Kurdistan Region, Iraq
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7
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Tryon VL, Garman HD, Loewy RL, Niendam TA. Links Between Human and Animal Models of Trauma and Psychosis: A Narrative Review. BIOLOGICAL PSYCHIATRY: COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2020; 6:154-165. [PMID: 33309566 DOI: 10.1016/j.bpsc.2020.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 09/08/2020] [Accepted: 09/16/2020] [Indexed: 11/26/2022]
Abstract
Traumatic experiences during development are associated with an increased risk of developing psychosis. Individuals with psychosis also report a higher rate of past trauma than healthy control subjects and worse outcomes than those who do not have these experiences. It is thought that traumatic experiences negatively impact specific neurobiological processes to confer this increased risk, and that systems affected by trauma are similarly changed in individuals with psychosis. Examining animal models of psychosis and the shared neurobiological changes in response to stressors can offer valuable insight into biological mechanisms that mediate symptoms and targets for intervention. This targeted review highlights a subset of models of psychosis across humans and animals, examines the similarities with the brain's response to stress and traumatic events, and discusses how these models may interact. Suggestions for future research are described.
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Affiliation(s)
- Valerie L Tryon
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, Davis
| | - Heather D Garman
- Department of Psychiatry, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, California
| | - Rachel L Loewy
- Department of Psychiatry, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, California
| | - Tara A Niendam
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, Davis.
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8
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Effects of ∆ 9-tetrahydrocannabinol on aversive memories and anxiety: a review from human studies. BMC Psychiatry 2020; 20:420. [PMID: 32842985 PMCID: PMC7448997 DOI: 10.1186/s12888-020-02813-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 08/05/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Posttraumatic stress disorder (PTSD) may stem from the formation of aberrant and enduring aversive memories. Some PTSD patients have recreationally used Cannabis, probably aiming at relieving their symptomatology. However, it is still largely unknown whether and how Cannabis or its psychotomimetic compound Δ9-tetrahydrocannabinol (THC) attenuates the aversive/traumatic memory outcomes. Here, we seek to review and discuss the effects of THC on aversive memory extinction and anxiety in healthy humans and PTSD patients. METHODS Medline, PubMed, Cochrane Library, and Central Register for Controlled Trials databases were searched to identify peer-reviewed published studies and randomized controlled trials in humans published in English between 1974 and July 2020, including those using only THC and THC combined with cannabidiol (CBD). The effect size of the experimental intervention under investigation was calculated. RESULTS At low doses, THC can enhance the extinction rate and reduce anxiety responses. Both effects involve the activation of cannabinoid type-1 receptors in discrete components of the corticolimbic circuitry, which could couterbalance the low "endocannabinoid tonus" reported in PTSD patients. The advantage of associating CBD with THC to attenuate anxiety while minimizing the potential psychotic or anxiogenic effect produced by high doses of THC has been reported. The effects of THC either alone or combined with CBD on aversive memory reconsolidation, however, are still unknown. CONCLUSIONS Current evidence from healthy humans and PTSD patients supports the THC value to suppress anxiety and aversive memory expression without producing significant adverse effects if used in low doses or when associated with CBD. Future studies are guaranteed to address open questions related to their dose ratios, administration routes, pharmacokinetic interactions, sex-dependent differences, and prolonged efficacy.
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9
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Feder A, Rutter SB, Schiller D, Charney DS. The emergence of ketamine as a novel treatment for posttraumatic stress disorder. RAPID ACTING ANTIDEPRESSANTS 2020; 89:261-286. [DOI: 10.1016/bs.apha.2020.05.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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10
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Speer KE, Semple S, Naumovski N, D'Cunha NM, McKune AJ. HPA axis function and diurnal cortisol in post-traumatic stress disorder: A systematic review. Neurobiol Stress 2019; 11:100180. [PMID: 31236437 PMCID: PMC6582238 DOI: 10.1016/j.ynstr.2019.100180] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 04/17/2019] [Accepted: 06/03/2019] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND There is inconsistency in the literature regarding the nature of hypothalamic-pituitary-adrenal (HPA) axis functionality in post-traumatic stress disorder (PTSD). PURPOSE The review aimed to investigate HPA axis functionality via the diurnal profile of cortisol as it relates to PTSD. METHODS The authors conducted a systematic review of the literature from June 2017 - March 2019 in accordance with The PRISMA Statement in the following four databases: PubMed, MEDLINE, ScienceDirect and PsycINFO with Full Text. The search strategy was limited to articles in English language, published in peer-reviewed journals within the last decade and human studies. Search terms included "post-traumatic stress disorder" OR "PTSD", AND "hypothalamic pituitary adrenal axis" OR "HPA axis" AND "diurnal cortisol" OR "cortisol". PTSD sufferers of all trauma types, genders and socioeconomic statuses were included provided there was a "healthy" control group and an inclusion of reporting on inter-group measurements of diurnal cortisol profiles as a portrayal of HPA axis functionality. RESULTS A total of 10 studies met the criteria for inclusion in this review. The association between HPA axis functionality and PTSD was evaluated by the measurement of salivary and/or plasma cortisol concentrations. Only two studies demonstrated an association between PTSD and diurnal cortisol when compared with respective control groups while three studies found no associations. The remaining five studies found partial, mostly negative associations between PTSD and diurnal cortisol. CONCLUSION Despite some indications of an association between PTSD and dysregulated HPA axis functionality as demonstrated by diurnal cortisol output, the current review has revealed mixed findings. As such, a complete understanding of HPA axis dysregulation as it relates to PTSD remains unestablished. Given the findings, further investigation into the relationship between PTSD trauma-exposed and non-PTSD trauma-exposed individuals and diurnal cortisol is warranted.
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Affiliation(s)
- Kathryn E. Speer
- Discipline of Sport and Exercise Science, Faculty of Health, University of Canberra, Canberra, ACT, 2601, Australia
- Research Institute for Sport and Exercise, University of Canberra, Canberra, ACT, 2601, Australia
- Collaborative Research in Bioactives and Biomarkers (CRIBB) Group, University of Canberra, Bruce, ACT, 2617, Australia
| | - Stuart Semple
- Discipline of Sport and Exercise Science, Faculty of Health, University of Canberra, Canberra, ACT, 2601, Australia
- Research Institute for Sport and Exercise, University of Canberra, Canberra, ACT, 2601, Australia
| | - Nenad Naumovski
- Faculty of Health, University of Canberra, Canberra, ACT, 2601, Australia
- Collaborative Research in Bioactives and Biomarkers (CRIBB) Group, University of Canberra, Bruce, ACT, 2617, Australia
- University of Canberra Health Research Institute (UC-HRI), Canberra, ACT, 2617, Australia
| | - Nathan M. D'Cunha
- Faculty of Health, University of Canberra, Canberra, ACT, 2601, Australia
- Collaborative Research in Bioactives and Biomarkers (CRIBB) Group, University of Canberra, Bruce, ACT, 2617, Australia
| | - Andrew J. McKune
- Discipline of Sport and Exercise Science, Faculty of Health, University of Canberra, Canberra, ACT, 2601, Australia
- Research Institute for Sport and Exercise, University of Canberra, Canberra, ACT, 2601, Australia
- Discipline of Biokinetics, Exercise and Leisure Sciences, School of Health Sciences, University of KwaZulu-Natal, Durban, KwaZulu-Natal, 4000, South Africa
- Collaborative Research in Bioactives and Biomarkers (CRIBB) Group, University of Canberra, Bruce, ACT, 2617, Australia
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11
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Bhattacharya S, Fontaine A, MacCallum PE, Drover J, Blundell J. Stress Across Generations: DNA Methylation as a Potential Mechanism Underlying Intergenerational Effects of Stress in Both Post-traumatic Stress Disorder and Pre-clinical Predator Stress Rodent Models. Front Behav Neurosci 2019; 13:113. [PMID: 31191267 PMCID: PMC6547031 DOI: 10.3389/fnbeh.2019.00113] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 05/07/2019] [Indexed: 12/12/2022] Open
Abstract
Although most humans will experience some type of traumatic event in their lifetime only a small set of individuals will go on to develop post-traumatic stress disorder (PTSD). Differences in sex, age, trauma type, and comorbidity, along with many other elements, contribute to the heterogenous manifestation of this disorder. Nonetheless, aberrant hypothalamus-pituitary-adrenal (HPA) axis activity, especially in terms of cortisol and glucocorticoid receptor (GR) alterations, has been postulated as a tenable factor in the etiology and pathophysiology of PTSD. Moreover, emerging data suggests that the harmful effects of traumatic stress to the HPA axis in PTSD can also propagate into future generations, making offspring more prone to psychopathologies. Predator stress models provide an ethical and ethologically relevant way to investigate tentative mechanisms that are thought to underlie this phenomenon. In this review article, we discuss findings from human and laboratory predator stress studies that suggest changes to DNA methylation germane to GRs may underlie the generational effects of trauma transmission. Understanding mechanisms that promote stress-induced psychopathology will represent a major advance in the field and may lead to novel treatments for such devastating, and often treatment-resistant trauma and stress-disorders.
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Affiliation(s)
- Sriya Bhattacharya
- Department of Psychology, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Audrey Fontaine
- Department of Psychology, Memorial University of Newfoundland, St. John's, NL, Canada.,Institut des Systèmes Intelligents et de Robotique (ISIR), Université Pierre et Marie Curie, Sorbonne Universités, Paris, France
| | - Phillip E MacCallum
- Department of Psychology, Memorial University of Newfoundland, St. John's, NL, Canada
| | - James Drover
- Department of Psychology, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Jacqueline Blundell
- Department of Psychology, Memorial University of Newfoundland, St. John's, NL, Canada
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12
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Lisieski MJ, Eagle AL, Conti AC, Liberzon I, Perrine SA. Single-Prolonged Stress: A Review of Two Decades of Progress in a Rodent Model of Post-traumatic Stress Disorder. Front Psychiatry 2018; 9:196. [PMID: 29867615 PMCID: PMC5962709 DOI: 10.3389/fpsyt.2018.00196] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 04/25/2018] [Indexed: 12/21/2022] Open
Abstract
Post-traumatic stress disorder (PTSD) is a common, costly, and often debilitating psychiatric condition. However, the biological mechanisms underlying this disease are still largely unknown or poorly understood. Considerable evidence indicates that PTSD results from dysfunction in highly-conserved brain systems involved in stress, anxiety, fear, and reward. Pre-clinical models of traumatic stress exposure are critical in defining the neurobiological mechanisms of PTSD, which will ultimately aid in the development of new treatments for PTSD. Single prolonged stress (SPS) is a pre-clinical model that displays behavioral, molecular, and physiological alterations that recapitulate many of the same alterations observed in PTSD, illustrating its validity and giving it utility as a model for investigating post-traumatic adaptations and pre-trauma risk and protective factors. In this manuscript, we review the present state of research using the SPS model, with the goals of (1) describing the utility of the SPS model as a tool for investigating post-trauma adaptations, (2) relating findings using the SPS model to findings in patients with PTSD, and (3) indicating research gaps and strategies to address them in order to improve our understanding of the pathophysiology of PTSD.
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Affiliation(s)
- Michael J Lisieski
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, United States
| | - Andrew L Eagle
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Alana C Conti
- Research and Development Service, John D. Dingell Veterans Affairs Medical Center, Detroit, MI, United States.,Department of Neurosurgery, Wayne State University School of Medicine, Detroit, MI, United States
| | - Israel Liberzon
- Department of Psychiatry, University of Michigan, Ann Arbor, MI, United States.,Mental Health Service, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, MI, United States
| | - Shane A Perrine
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, United States
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Trollope AF, Mifsud KR, Saunderson EA, Reul JMHM. Molecular and Epigenetic Mechanisms Underlying Cognitive and Adaptive Responses to Stress. EPIGENOMES 2017; 1:17. [PMID: 31921466 PMCID: PMC6952278 DOI: 10.3390/epigenomes1030017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Consolidation of contextual memories after a stressful encounter is essential for the survival of an organism and in allowing a more appropriate response to be elicited should the perceived threat reoccur. Recent evidence has explored the complex role that epigenetic mechanisms play in the formation of such memories, and the underlying signaling pathways are becoming more apparent. The glucocorticoid receptor (GR) has been shown to play a key role in these events having both genomic and non-genomic actions in the brain. GR has been shown to interact with the extracellular signal-regulated kinase mitogen-activated protein kinase (ERK MAPK) signaling pathway which, in concert, drives epigenetic modifications and chromatin remodeling, resulting in gene induction and memory consolidation. Evidence indicates that stressful events can have an effect on the offspring in utero, and that epigenetic marks altered early in life may persist into adulthood. A new and controversial area of research, however, suggests that epigenetic modifications could be inherited through the germline, a concept known as transgenerational epigenetics. This review explores the role that epigenetic processes play in the central nervous system, specifically in the consolidation of stress-induced memories, the concept of transgenerational epigenetic inheritance, and the potential role of epigenetics in revolutionizing the treatment of stress-related disorders through the emerging field of pharmacoepigenetics and personalized medical treatment.
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Affiliation(s)
- Alexandra F. Trollope
- Neuro-Epigenetics Research Group, Bristol Medical School, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK
- Department of Anatomy, College of Medicine and Dentistry, James Cook University, Townsville 4811, Australia
| | - Karen R. Mifsud
- Neuro-Epigenetics Research Group, Bristol Medical School, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK
| | - Emily A. Saunderson
- Neuro-Epigenetics Research Group, Bristol Medical School, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, UK
| | - Johannes M. H. M. Reul
- Neuro-Epigenetics Research Group, Bristol Medical School, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK
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Wrocklage KM, Averill LA, Cobb Scott J, Averill CL, Schweinsburg B, Trejo M, Roy A, Weisser V, Kelly C, Martini B, Harpaz-Rotem I, Southwick SM, Krystal JH, Abdallah CG. Cortical thickness reduction in combat exposed U.S. veterans with and without PTSD. Eur Neuropsychopharmacol 2017; 27:515-525. [PMID: 28279623 PMCID: PMC5429865 DOI: 10.1016/j.euroneuro.2017.02.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 01/20/2017] [Accepted: 02/21/2017] [Indexed: 12/26/2022]
Abstract
We investigated the extent of cortical thinning in U.S. Veterans exposed to combat who varied in the severity of their posttraumatic stress disorder (PTSD) symptoms. In addition, we explored the neural correlates of PTSD symptom dimensions and the interactive effects of combat exposure and PTSD upon cortical thickness. Sixty-nine combat exposed Veterans completed high-resolution magnetic resonance imaging (MRI) scans to estimate cortical thickness. The Clinician Administered PTSD Scale (CAPS) and Combat Exposure Scale (CES) assessments were completed to measure current PTSD and historical combat severity, respectively. PTSD symptom dimensions (numbing, avoidance, reexperiencing, anxious arousal, and dysphoric arousal) were studied. Vertex-wise whole cerebrum analyses were conducted. We found widespread negative correlations between CAPS severity and cortical thickness, particularly within the prefrontal cortex. This prefrontal correlation remained significant after controlling for depression severity, medication status, and other potential confounds. PTSD dimensions, except anxious arousal, negatively correlated with cortical thickness in various unique brain regions. CES negatively correlated with cortical thickness in the left lateral prefrontal, regardless of PTSD diagnosis. A significant interaction between CES and PTSD diagnosis was found, such that CES negatively correlated with cortical thickness in the non-PTSD, but not in the PTSD, participants. The results underscore the severity of cortical thinning in U.S. Veterans suffering from high level of PTSD symptoms, as well as in Veterans with no PTSD diagnosis but severe combat exposure. The latter finding raises considerable concerns about a concealed injury potentially related to combat exposure in the post-9/11 era.
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Affiliation(s)
- Kristen M Wrocklage
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Lynnette A Averill
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - J Cobb Scott
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; VISN4 Mental Illness Research, Education, and Clinical Center at the Philadelphia VA Medical Center, Philadelphia, Pennsylvania
| | - Christopher L Averill
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Brian Schweinsburg
- Department of Psychiatry, University of Connecticut Medical Center, Farmington, CT, United States
| | - Marcia Trejo
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Alicia Roy
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Valerie Weisser
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Christopher Kelly
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Brenda Martini
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Ilan Harpaz-Rotem
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Steven M Southwick
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - John H Krystal
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Chadi G Abdallah
- National Center for PTSD - Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, United States; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States.
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15
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Andrews CJ, Reisner AD. Neurological and neuropsychological consequences of electrical and lightning shock: review and theories of causation. Neural Regen Res 2017; 12:677-686. [PMID: 28616016 PMCID: PMC5461597 DOI: 10.4103/1673-5374.206636] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/24/2017] [Indexed: 12/14/2022] Open
Abstract
Injuries from lightning and electrical injuries involve multiple systems of the body, however neurological symptoms are very widely reported. A disabling neuropsychological syndrome is also noted. This paper presents a comprehensive review of neurological and neuropsychological symptoms. Partial theories of causation for these injuries have been advanced, however, there is no convincing explanation for both delay in onset of symptoms and also the genesis of the neuropsychological syndrome. A theory of causation is proposed which satisfies both these constraints. This theory suggests circulating hormones such as cortisol, together with nitric oxide and oxidant free radicals from glutamatergic hyper-stimulation, act on tissues remote from the injury path including the hippocampus. This theory opens a research path to explore treatment options.
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Affiliation(s)
- Christopher J. Andrews
- Faculty of Medicine - The University of Queensland, Herston, Australia; Lightning and Electrical Injuries, Mt Ommaney Family Practice, Mt Ommaney, Brisbane, Australia
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16
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Averill LA, Purohit P, Averill CL, Boesl MA, Krystal JH, Abdallah CG. Glutamate dysregulation and glutamatergic therapeutics for PTSD: Evidence from human studies. Neurosci Lett 2016; 649:147-155. [PMID: 27916636 DOI: 10.1016/j.neulet.2016.11.064] [Citation(s) in RCA: 122] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 11/18/2016] [Accepted: 11/30/2016] [Indexed: 12/20/2022]
Abstract
Posttraumatic stress disorder (PTSD) is a chronic and debilitating psychiatric disorder afflicting millions of individuals across the world. While the availability of robust pharmacologic interventions is quite lacking, our understanding of the putative neurobiological underpinnings of PTSD has significantly increased over the past two decades. Accumulating evidence demonstrates aberrant glutamatergic function in mood, anxiety, and trauma-related disorders and dysfunction in glutamate neurotransmission is increasingly considered a cardinal feature of stress-related psychiatric disorders including PTSD. As part of a PTSD Special Issue, this mini-review provides a concise discussion of (1) evidence of glutamatergic abnormalities in PTSD, with emphasis on human subjects data; (2) glutamate-modulating agents as potential alternative pharmacologic treatments for PTSD; and (3) selected gaps in the literature and related future directions.
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Affiliation(s)
- Lynnette A Averill
- Clinical Neurosciences Division, United States Department of Veterans Affairs, National Center for Posttraumatic Stress Disorder, VA Connecticut Healthcare System, 950 Campbell Avenue, West Haven, CT, 06516, USA; Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA.
| | - Prerana Purohit
- Clinical Neurosciences Division, United States Department of Veterans Affairs, National Center for Posttraumatic Stress Disorder, VA Connecticut Healthcare System, 950 Campbell Avenue, West Haven, CT, 06516, USA; Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA
| | - Christopher L Averill
- Clinical Neurosciences Division, United States Department of Veterans Affairs, National Center for Posttraumatic Stress Disorder, VA Connecticut Healthcare System, 950 Campbell Avenue, West Haven, CT, 06516, USA; Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA
| | - Markus A Boesl
- Clinical Neurosciences Division, United States Department of Veterans Affairs, National Center for Posttraumatic Stress Disorder, VA Connecticut Healthcare System, 950 Campbell Avenue, West Haven, CT, 06516, USA; Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA
| | - John H Krystal
- Clinical Neurosciences Division, United States Department of Veterans Affairs, National Center for Posttraumatic Stress Disorder, VA Connecticut Healthcare System, 950 Campbell Avenue, West Haven, CT, 06516, USA; Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA
| | - Chadi G Abdallah
- Clinical Neurosciences Division, United States Department of Veterans Affairs, National Center for Posttraumatic Stress Disorder, VA Connecticut Healthcare System, 950 Campbell Avenue, West Haven, CT, 06516, USA; Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA
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17
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O'Doherty DCM, Chitty KM, Saddiqui S, Bennett MR, Lagopoulos J. A systematic review and meta-analysis of magnetic resonance imaging measurement of structural volumes in posttraumatic stress disorder. Psychiatry Res 2015; 232:1-33. [PMID: 25735885 DOI: 10.1016/j.pscychresns.2015.01.002] [Citation(s) in RCA: 232] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 11/15/2014] [Accepted: 01/08/2015] [Indexed: 12/15/2022]
Abstract
Posttraumatic stress disorder (PTSD) is a debilitating condition associated with mild to moderate cognitive impairment and with a prevalence rate of up to 22% in veterans. This systematic review and quantitative meta-analysis explore volumetric differences of three key structural brain regions (hippocampus, amygdala and anterior cingulate cortex (ACC)), all of which have been implicated in dysfunction of both salience network (SN) and default mode network (DMN) in PTSD sufferers. A literature search was conducted in Embase, Medline, PubMed and PsycINFO in May 2013. Fifty-nine volumetric analyses from 44 articles were examined and included (36 hippocampus, 14 amygdala and nine ACC) with n=846 PTSD participants, n=520 healthy controls (HCs) and n=624 traumatised controls (TCs). Nine statistical tests were performed for each of the three regions of interest (ROIs), measuring volume differences in PTSD subjects, healthy and traumatised controls. Hippocampal volume was reduced in subjects with PTSD, with a greater reduction in the left hippocampus. A medium effect size reduction was found in bilateral amygdala volume when compared with findings in healthy controls; however, no significant differences in amygdala volume between PTSD subjects and trauma-exposed controls were found. Significant volume reductions were found bilaterally in the ACC. While often well matched with their respective control groups, the samples of PTSD subjects composed from the source studies used in the meta-analyses are limited in their homogeneity. The current findings of reduced hippocampal volume in subjects with PTSD are consistent with the existing literature. Amygdala volumes did not show significant reductions in PTSD subjects when compared with volumes in trauma-exposed controls-congruous with reported symptoms of hypervigilance and increased propensity in acquisition of conditioned fear memories-but a significant reduction was found in the combined left and right hemisphere volume analysis when compared with healthy controls. Bilateral volume reductions in the ACC may underpin the attentional deficits and inabilities to modulate emotions that are characteristically associated with PTSD patients.
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Affiliation(s)
- Daniel C M O'Doherty
- Brain and Mind Research Institute, University of Sydney, 100 Mallett Street, Camperdown, NSW 2050, Australia.
| | - Kate M Chitty
- Brain and Mind Research Institute, University of Sydney, 100 Mallett Street, Camperdown, NSW 2050, Australia.
| | - Sonia Saddiqui
- Faculty of Human Sciences, Macquarie University, Sydney, Australia.
| | - Maxwell R Bennett
- Brain and Mind Research Institute, University of Sydney, 100 Mallett Street, Camperdown, NSW 2050, Australia.
| | - Jim Lagopoulos
- Brain and Mind Research Institute, University of Sydney, 100 Mallett Street, Camperdown, NSW 2050, Australia.
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18
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Zhang LM, Zhou WW, Ji YJ, Li Y, Zhao N, Chen HX, Xue R, Mei XG, Zhang YZ, Wang HL, Li YF. Anxiolytic effects of ketamine in animal models of posttraumatic stress disorder. Psychopharmacology (Berl) 2015; 232:663-72. [PMID: 25231918 DOI: 10.1007/s00213-014-3697-9] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 07/28/2014] [Indexed: 01/13/2023]
Abstract
This study investigated the effectiveness of ketamine, a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, in alleviating the enhanced anxiety and fear response in both a mouse model of PTSD induced by inescapable electric foot shocks and a rat model of PTSD induced by a time-dependent sensitization (TDS) procedure. First, we evaluated the effect of ketamine on behavioral deficits in a mouse model of PTSD that consisted of foot shocks followed by three situational reminders. Our results showed that the aversive procedure induced several behavioral deficiencies, such as increased freezing behavior and anxiety, as well as reduced time spent in an aversive-like context, which were reversed by repeated treatment with ketamine. The effect of ketamine on behavioral changes after exposure to TDS was also investigated, and the levels of brain-derived neurotrophic factor (BDNF) in the hippocampus were measured. The results revealed that after TDS, the rats showed a significant increase in contextual freezing and a decrease in the percentage of time spent in and numbers of entries into open arms in the elevated plus maze test. As a positive control drug, sertraline (Ser, 15 mg/kg, i.g.), a selective serotonin reuptake inhibitor (SSRI) ameliorated these behavioral deficits. These behavioral effects were mimicked by chronic ketamine treatment. Furthermore, ketamine normalized the decreased BDNF level in the hippocampus in post-TDS rats. Taken together, these results suggest that ketamine exerts a therapeutic effect on PTSD that might be at least partially mediated by an influence on BDNF signaling in the hippocampus.
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Affiliation(s)
- Li-Ming Zhang
- Department of New Drug Evaluation, Beijing Institute of Pharmacology and Toxicology, 27 Taiping Road, Haidian, Beijing, 100850, China
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19
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Daskalakis NP, Yehuda R, Diamond DM. Animal models in translational studies of PTSD. Psychoneuroendocrinology 2013; 38:1895-911. [PMID: 23845512 DOI: 10.1016/j.psyneuen.2013.06.006] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 06/05/2013] [Accepted: 06/05/2013] [Indexed: 01/29/2023]
Abstract
Understanding the neurobiological mechanisms of post-traumatic stress disorder (PTSD) is of vital importance for developing biomarkers and more effective pharmacotherapy for this disorder. The design of bidirectional translational studies addressing all facets of PTSD is needed. Animal models of PTSD are needed not only to capture the complexity of PTSD behavioral characteristics, but also to address experimentally the influence of variety of factors which might determine an individual's vulnerability or resilience to trauma, e.g., genetic predisposition, early-life experience and social support. The current review covers recent translational approaches to bridge the gap between human and animal PTSD research and to create a framework for discovery of biomarkers and novel therapeutics.
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Affiliation(s)
- Nikolaos P Daskalakis
- Traumatic Stress Studies Division & Laboratory of Molecular Neuropsychiatry, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, USA; Mental Health Care Center, PTSD Clinical Research Program & Laboratory of Clinical Neuroendocrinology and Neurochemistry, James J. Peters Veterans Affairs Medical Center, Bronx, USA
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20
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Zoladz PR, Fleshner M, Diamond DM. Differential effectiveness of tianeptine, clonidine and amitriptyline in blocking traumatic memory expression, anxiety and hypertension in an animal model of PTSD. Prog Neuropsychopharmacol Biol Psychiatry 2013; 44:1-16. [PMID: 23318688 DOI: 10.1016/j.pnpbp.2013.01.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 12/22/2012] [Accepted: 01/04/2013] [Indexed: 12/21/2022]
Abstract
Individuals exposed to life-threatening trauma are at risk for developing post-traumatic stress disorder (PTSD), a debilitating condition that involves persistent anxiety, intrusive memories and several physiological disturbances. Current pharmacotherapies for PTSD manage only a subset of these symptoms and typically have adverse side effects which limit their overall effectiveness. We evaluated the effectiveness of three different pharmacological agents to ameliorate a broad range of PTSD-like symptoms in our established predator-based animal model of PTSD. Adult male Sprague-Dawley rats were given 1-h cat exposures on two occasions that were separated by 10 days, in conjunction with chronic social instability. Beginning 24 h after the first cat exposure, rats received daily injections of amitriptyline, clonidine, tianeptine or vehicle. Three weeks after the second cat exposure, all rats underwent a battery of behavioral and physiological tests. The vehicle-treated, psychosocially stressed rats demonstrated a robust fear memory for the two cat exposures, as well as increased anxiety expressed on the elevated plus maze, an exaggerated startle response, elevated heart rate and blood pressure, reduced growth rate and increased adrenal gland weight, relative to the vehicle-treated, non-stressed (control) rats. Neither amitriptyline nor clonidine was effective at blocking the entire cluster of stress-induced sequelae, and each agent produced adverse side effects in control subjects. Only the antidepressant tianeptine completely blocked the effects of psychosocial stress on all of the physiological and behavioral measures that were examined. These findings illustrate the differential effectiveness of these three treatments to block components of PTSD-like symptoms in rats, and in particular, reveal the profile of tianeptine as the most effective of all three agents.
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Affiliation(s)
- Phillip R Zoladz
- Department of Psychology, Sociology & Criminal Justice, Ohio Northern University, Ada, OH, USA
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21
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Abstract
There are sex differences in the prevalence and presentation of many psychiatric disorders. Various trends in symptomatology have emerged that are thought to be linked to periods of hormonal fluctuations such as with menses, pregnancy or menopause. With data from animal and human studies, it has become clear that there is an important interplay between the serotonergic system and gonadal hormones. The majority of the research to date has focused on the influence that estrogen has within the CNS and, in particular, how it leads to an overall increase in serotonin synthesis and availability. In reviewing this female-specific topic we hope to raise awareness to sex/gender differences in psychopathology, help identify at-risk populations and consider development of new treatment options. Future research will also need to consider the influence that progesterone and oxytocin may have on sex-specific psychopathology as well as incorporate neuroimaging and consider the influence of hormones on the serotonergic system at a genetic level.
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Affiliation(s)
- Elise Hall
- Department of Psychiatry & Behavioural Neurosciences, Centre for Mountain Health Services, McMaster University, 100 West 5th, Box 585, Hamilton, ON, Canada
| | - Meir Steiner
- Women's Health Concerns Clinic, St Joseph's Healthcare, Hamilton, ON, Canada
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22
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Mifsud KR, Gutièrrez-Mecinas M, Trollope AF, Collins A, Saunderson EA, Reul JMHM. Epigenetic mechanisms in stress and adaptation. Brain Behav Immun 2011; 25:1305-15. [PMID: 21704151 DOI: 10.1016/j.bbi.2011.06.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 05/26/2011] [Accepted: 06/07/2011] [Indexed: 12/22/2022] Open
Abstract
Epigenetic mechanisms are processes at the level of the chromatin that control the expression of genes but their role in neuro-immuno-endocrine communication is poorly understood. This review focuses on epigenetic modifications induced by a range of stressors, both physical and psychological, and examines how these variations can affect the biological activity of cells. It is clear that epigenetic modifications are critical in explaining how environmental factors, which have no effect on the DNA sequence, can have such profound, long-lasting influences on both physiology and behavior. A signaling pathway involving activation of MEK-ERK1/2, MSK1, and Elk-1 signaling molecules has been identified in the hippocampus which results in the phospho-acetylation of histone H3 and modification of gene expression including up-regulation of immediate early genes such as c-Fos. This pathway can be induced by a range of challenging experiences including forced swimming, Morris water maze learning, fear conditioning and exposure to the radial maze. Glucocorticoid (GC) hormones, released as part of the stress response and acting via glucocorticoid receptors (GRs), enhance signaling through the ERK1/2/MSK1-Elk-1 pathway and thereby increase the impact on epigenetic and gene expression mechanisms. The role of synergetic interactions between these pathways in adaptive responses to stress and learning and memory paradigms is discussed, in addition we speculate on their potential role in immune function.
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Affiliation(s)
- Karen R Mifsud
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, United Kingdom
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23
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Long-lasting behavioral responses to stress involve a direct interaction of glucocorticoid receptors with ERK1/2-MSK1-Elk-1 signaling. Proc Natl Acad Sci U S A 2011; 108:13806-11. [PMID: 21808001 DOI: 10.1073/pnas.1104383108] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Stressful events are known to have a long-term impact on future behavioral stress responses. Previous studies suggested that both glucocorticoid hormones and glutamate acting via glucocorticoid receptors (GRs) and N-methyl D-aspartate (NMDA) receptors, respectively, are of critical importance for the consolidation of these long-lasting behavioral responses at the dentate gyrus, the gateway of the hippocampal formation. We found that an acute psychologically stressful event resulted in ERK1/2 phosphorylation (pERK1/2), which within 15 min led to the activation of the nuclear kinases MSK1 and Elk-1 in granule neurons of the dentate gyrus. Next, MSK1 and Elk-1 activation evoked serine-10 phosphorylation and lysine-14 acetylation in histone H3, resulting in the induction of the neuroplasticity-associated immediate-early genes c-Fos and Egr-1 in these neurons. The pERK1/2-mediated activation of MSK1 and Elk-1 required a rapid protein-protein interaction between pERK1/2 and activated GRs. This is a unique nongenomic mechanism of glucocorticoid hormone action in dentate gyrus granule neurons on long-lasting behavioral responses to stress involving direct cross-talk of GRs with ERK1/2-MSK1-Elk-1 signaling to the nucleus.
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Steckler T, Risbrough V. Pharmacological treatment of PTSD - established and new approaches. Neuropharmacology 2011; 62:617-27. [PMID: 21736888 DOI: 10.1016/j.neuropharm.2011.06.012] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 06/02/2011] [Accepted: 06/17/2011] [Indexed: 11/24/2022]
Abstract
A large proportion of humans will experience a traumatic event at least once in their lifetime, with up to 10% then going on to developing posttraumatic stress disorder (PTSD). In this review we will discuss established pharmacological interventions for PTSD as well as highlight novel therapeutic strategies undergoing extensive pre-clinical research as well as ongoing clinical research. Such strategies include prophylactic treatments and use of pharmacotherapy as adjunctive treatment with established trauma-focused psychological therapies. These potential treatment approaches include modulation of stress effects on memory consolidation after trauma (e.g., glucocorticoid, corticotropin-releasing factor and norepinephrine signalling modulators), as well as putative cognitive enhancers that target mechanisms of conditioned fear extinction and reconsolidation (e.g., glucocorticoid receptor modulators and modulators of glutamate signalling such as positive allosteric modulators of glutamate receptors, glycine transporter inhibitors, or glycine agonists). We will discuss evidence for and against these potential novel treatment strategies and their limitations. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.
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25
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Peterlin BL, Nijjar SS, Tietjen GE. Post-traumatic stress disorder and migraine: epidemiology, sex differences, and potential mechanisms. Headache 2011; 51:860-8. [PMID: 21592096 DOI: 10.1111/j.1526-4610.2011.01907.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Migraine is a common, often disabling disorder associated with a significant personal and societal burden. The presence of post-traumatic stress disorder (PTSD) may increase this disability substantially. Migraine and PTSD are both up to 3 times more common in women than in men. The divergence in prevalence rates of migraine and PTSD that occurs between the sexes after puberty suggests that gonadal hormones play an important role. In addition, the preponderance of PTSD in women may be related to their higher rates of interpersonal trauma, the most common cause of PTSD. However, recent data suggest that although the odds of PTSD are increased in both women and men with episodic migraine, this association is stronger in men than women. In this paper, we examine the epidemiology of PTSD and migraine, with an emphasis on the known sex differences. We then discuss the neurobiological changes associated with PTSD, the current hypotheses for the mechanisms relating PTSD and migraine, and the treatment implications of these findings.
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Affiliation(s)
- B Lee Peterlin
- Department of Neurology, Johns Hopkins University, Bayview Medical Center, Baltimore, MD, USA.
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26
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Peterlin BL, Rosso AL, Sheftell FD, Libon DJ, Mossey JM, Merikangas KR. Post-traumatic stress disorder, drug abuse and migraine: new findings from the National Comorbidity Survey Replication (NCS-R). Cephalalgia 2010; 31:235-44. [PMID: 20813779 DOI: 10.1177/0333102410378051] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Post-traumatic stress disorder (PTSD) has been shown to be associated with migraine and drug abuse. METHODS This was an analysis of data from the National Comorbidity Survey Replication (NCS-R) to evaluate the association of PTSD in those with episodic migraine (EM) and chronic daily headache (CDH). RESULTS Our sample consisted of 5,692 participants. Lifetime and 12-month prevalence rates of PTSD were increased in those with EM and CDH. After adjustments, the lifetime odds ratio (OR) of PTSD was greater in those with EM (OR 3.07 confidence interval [CI]: 2.12, 4.46) compared to those without headache; was greater in men than women with EM (men: OR 6.86; CI: 3.11, 15.11; women: OR 2.77; CI: 1.83, 4.21); and was comparable or greater than the association between migraine with depression or anxiety. The lifetime OR of PTSD was also increased in CDH sufferers. The OR of illicit drug abuse was not increased in those with EM or CDH unless co-occurring with PTSD or depression. CONCLUSION The lifetime and 12-month OR of PTSD is increased in those with migraine or CDH, and is greater in men than women with migraine. The lifetime and 12-month OR of illicit drug abuse is not increased in those with migraine or CDH unless co-occurring with PTSD or depression.
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Affiliation(s)
- B Lee Peterlin
- Johns Hopkins University, Bayview Medical Center, Baltimore, MD 21224, USA.
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Exercise improves cognitive responses to psychological stress through enhancement of epigenetic mechanisms and gene expression in the dentate gyrus. PLoS One 2009; 4:e4330. [PMID: 19180197 PMCID: PMC2628725 DOI: 10.1371/journal.pone.0004330] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2008] [Accepted: 10/28/2008] [Indexed: 11/19/2022] Open
Abstract
Background We have shown previously that exercise benefits stress resistance and stress coping capabilities. Furthermore, we reported recently that epigenetic changes related to gene transcription are involved in memory formation of stressful events. In view of the enhanced coping capabilities in exercised subjects we investigated epigenetic, gene expression and behavioral changes in 4-weeks voluntarily exercised rats. Methodology/Principal Findings Exercised and control rats coped differently when exposed to a novel environment. Whereas the control rats explored the new cage for the complete 30-min period, exercised animals only did so during the first 15 min after which they returned to sleeping or resting behavior. Both groups of animals showed similar behavioral responses in the initial forced swim session. When re-tested 24 h later however the exercised rats showed significantly more immobility behavior and less struggling and swimming. If rats were killed at 2 h after novelty or the initial swim test, i.e. at the peak of histone H3 phospho-acetylation and c-Fos induction, then the exercised rats showed a significantly higher number of dentate granule neurons expressing the histone modifications and immediate-early gene induction. Conclusions/Significance Thus, irrespective of the behavioral response in the novel cage or initial forced swim session, the impact of the event at the dentate gyrus level was greater in exercised rats than in control animals. Furthermore, in view of our concept that the neuronal response in the dentate gyrus after forced swimming is involved in memory formation of the stressful event, the observations in exercised rats of enhanced neuronal responses as well as higher immobility responses in the re-test are consistent with the reportedly improved cognitive performance in these animals. Thus, improved stress coping in exercised subjects seems to involve enhanced cognitive capabilities possibly resulting from distinct epigenetic mechanisms in dentate gyrus neurons.
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