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Bertollo AG, Galvan ACL, Dallagnol C, Cortez AD, Ignácio ZM. Early Life Stress and Major Depressive Disorder-An Update on Molecular Mechanisms and Synaptic Impairments. Mol Neurobiol 2024; 61:6469-6483. [PMID: 38307968 DOI: 10.1007/s12035-024-03983-2] [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: 07/05/2023] [Accepted: 01/21/2024] [Indexed: 02/04/2024]
Abstract
Early life stress (ELS), characterized as abuse, neglect, and abandonment, can cause several adverse consequences in the lives of affected individuals. ELS experiences can affect an individual's development in variable ways, persisting in the long term and promoting lasting impacts, considering that early exposure to stressors can be biologically incorporated, as prolonged stimulation of stress response systems affects the development of the brain structure and other body systems, increasing the risk of diseases associated with stress and cognitive impairment. This type of stress increases the risk of developing major depressive disorder (MDD) in a severe form that does not respond adequately to traditional antidepressant treatments. Several alterations are studied as mechanisms that relate ELS with MDD, such as epigenetic alterations, neurotransmitters, and neuronal signaling. This review discusses research that brings evidence about the ELS mechanisms involved in synaptic impairments and MDD. The processes involved in epigenetic changes and the HPA axis are highlighted, as well as changes in neurotransmitters and neuronal signaling mechanisms.
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Affiliation(s)
- Amanda Gollo Bertollo
- Laboratory of Physiology Pharmacology and Psychopathology, Graduate Program in Biomedical Sciences, Federal University of Fronteira Sul, Chapecó, SC, 89815-899, Brazil
| | - Agatha Carina Leite Galvan
- Laboratory of Physiology Pharmacology and Psychopathology, Graduate Program in Biomedical Sciences, Federal University of Fronteira Sul, Chapecó, SC, 89815-899, Brazil
| | - Claudia Dallagnol
- Laboratory of Physiology Pharmacology and Psychopathology, Graduate Program in Biomedical Sciences, Federal University of Fronteira Sul, Chapecó, SC, 89815-899, Brazil
| | - Arthur Dellazeri Cortez
- Laboratory of Physiology Pharmacology and Psychopathology, Graduate Program in Biomedical Sciences, Federal University of Fronteira Sul, Chapecó, SC, 89815-899, Brazil
| | - Zuleide Maria Ignácio
- Laboratory of Physiology Pharmacology and Psychopathology, Graduate Program in Biomedical Sciences, Federal University of Fronteira Sul, Chapecó, SC, 89815-899, Brazil.
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Reemst K, Kracht L, Kotah JM, Rahimian R, van Irsen AAS, Congrains Sotomayor G, Verboon LN, Brouwer N, Simard S, Turecki G, Mechawar N, Kooistra SM, Eggen BJL, Korosi A. Early-life stress lastingly impacts microglial transcriptome and function under basal and immune-challenged conditions. Transl Psychiatry 2022; 12:507. [PMID: 36481769 PMCID: PMC9731997 DOI: 10.1038/s41398-022-02265-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 11/18/2022] [Accepted: 11/23/2022] [Indexed: 12/13/2022] Open
Abstract
Early-life stress (ELS) leads to increased vulnerability to psychiatric disorders including depression later in life. Neuroinflammatory processes have been implicated in ELS-induced negative health outcomes, but how ELS impacts microglia, the main tissue-resident macrophages of the central nervous system, is unknown. Here, we determined the effects of ELS-induced by limited bedding and nesting material during the first week of life (postnatal days [P]2-9) on microglial (i) morphology; (ii) hippocampal gene expression; and (iii) synaptosome phagocytic capacity in male pups (P9) and adult (P200) mice. The hippocampus of ELS-exposed adult mice displayed altered proportions of morphological subtypes of microglia, as well as microglial transcriptomic changes related to the tumor necrosis factor response and protein ubiquitination. ELS exposure leads to distinct gene expression profiles during microglial development from P9 to P200 and in response to an LPS challenge at P200. Functionally, synaptosomes from ELS-exposed mice were phagocytosed less by age-matched microglia. At P200, but not P9, ELS microglia showed reduced synaptosome phagocytic capacity when compared to control microglia. Lastly, we confirmed the ELS-induced increased expression of the phagocytosis-related gene GAS6 that we observed in mice, in the dentate gyrus of individuals with a history of child abuse using in situ hybridization. These findings reveal persistent effects of ELS on microglial function and suggest that altered microglial phagocytic capacity is a key contributor to ELS-induced phenotypes.
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Affiliation(s)
- Kitty Reemst
- grid.7177.60000000084992262Swammerdam Institute for Life Sciences, Center for Neuroscience, Brain Plasticity Group, University of Amsterdam, Amsterdam, Science Park 904, 1098 XH The Netherlands
| | - Laura Kracht
- grid.4494.d0000 0000 9558 4598Department of Biomedical Sciences of Cells & Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Janssen M. Kotah
- grid.7177.60000000084992262Swammerdam Institute for Life Sciences, Center for Neuroscience, Brain Plasticity Group, University of Amsterdam, Amsterdam, Science Park 904, 1098 XH The Netherlands
| | - Reza Rahimian
- grid.412078.80000 0001 2353 5268McGill Group for Suicide Studies, Douglas Hospital Research Center, Montreal, QC H4H 1R3 Canada ,grid.14709.3b0000 0004 1936 8649Department of Psychiatry, McGill University, Montreal, QC H3A 1A1 Canada
| | - Astrid A. S. van Irsen
- grid.7177.60000000084992262Swammerdam Institute for Life Sciences, Center for Neuroscience, Brain Plasticity Group, University of Amsterdam, Amsterdam, Science Park 904, 1098 XH The Netherlands
| | - Gonzalo Congrains Sotomayor
- grid.7177.60000000084992262Swammerdam Institute for Life Sciences, Center for Neuroscience, Brain Plasticity Group, University of Amsterdam, Amsterdam, Science Park 904, 1098 XH The Netherlands
| | - Laura N. Verboon
- grid.7177.60000000084992262Swammerdam Institute for Life Sciences, Center for Neuroscience, Brain Plasticity Group, University of Amsterdam, Amsterdam, Science Park 904, 1098 XH The Netherlands
| | - Nieske Brouwer
- grid.4494.d0000 0000 9558 4598Department of Biomedical Sciences of Cells & Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Sophie Simard
- grid.412078.80000 0001 2353 5268McGill Group for Suicide Studies, Douglas Hospital Research Center, Montreal, QC H4H 1R3 Canada ,grid.14709.3b0000 0004 1936 8649Department of Psychiatry, McGill University, Montreal, QC H3A 1A1 Canada
| | - Gustavo Turecki
- grid.412078.80000 0001 2353 5268McGill Group for Suicide Studies, Douglas Hospital Research Center, Montreal, QC H4H 1R3 Canada ,grid.14709.3b0000 0004 1936 8649Department of Psychiatry, McGill University, Montreal, QC H3A 1A1 Canada
| | - Naguib Mechawar
- grid.412078.80000 0001 2353 5268McGill Group for Suicide Studies, Douglas Hospital Research Center, Montreal, QC H4H 1R3 Canada ,grid.14709.3b0000 0004 1936 8649Department of Psychiatry, McGill University, Montreal, QC H3A 1A1 Canada
| | - Susanne M. Kooistra
- grid.4494.d0000 0000 9558 4598Department of Biomedical Sciences of Cells & Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Bart J. L. Eggen
- grid.4494.d0000 0000 9558 4598Department of Biomedical Sciences of Cells & Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Aniko Korosi
- Swammerdam Institute for Life Sciences, Center for Neuroscience, Brain Plasticity Group, University of Amsterdam, Amsterdam, Science Park 904, 1098 XH, The Netherlands.
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Down-regulation of MST1 in hippocampus protects against stress-induced depression-like behaviours and synaptic plasticity impairments. Brain Behav Immun 2021; 94:196-209. [PMID: 33607238 DOI: 10.1016/j.bbi.2021.02.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 01/26/2021] [Accepted: 02/05/2021] [Indexed: 12/15/2022] Open
Abstract
Depression is a common mental disorder, and its main environmental risk factor is chronic stress. The activation of mammalian STE20-like kinase 1 (MST1), a key factor involved in the underlying pathophysiology of stress, can trigger synaptic plasticity impairment, neuronal dysfunction and neuroinflammation. However, it is unclear whether down-regulation of MST1 in the hippocampus protects against stress-induced behavioural dysfunctions. In this study, three mouse models were used to assess the role of MST1 in stress. Various behavioural tests, in vivo electrophysiological recordings, Western blotting, Golgi staining and immunofluorescence assay were used. The data showed that the level of phospho-MST1 (T183) was significantly increased in the hippocampus of mice subjected to chronic unpredictable mild stress (CUMS) and that mice with MST1 overexpression showed depression-like behaviours. Importantly, the impairment of cognitive functions and the hippocampal synaptic plasticity induced by CUMS were significantly improved by MST1 knockdown, suggesting that MST1 down-regulation effectively protected against stress-induced behavioural dysfunctions. Moreover, MST1 knockdown suppressed CUMS-induced microglial activation, reduced the abnormal expression of inflammatory cytokines and impeded the activation of p38, implying that the antidepressant-like effects of MST1 knockdown were associated with inhibiting the p38 pathway. These findings suggest that hippocampal MST1 is an essential regulator of stress, which can be an ideal target for the development of antidepressants in the future.
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HUZARD D, RAPPENEAU V, MEIJER OC, TOUMA C, ARANGO-LIEVANO M, GARABEDIAN MJ, JEANNETEAU F. Experience and activity-dependent control of glucocorticoid receptors during the stress response in large-scale brain networks. Stress 2021; 24:130-153. [PMID: 32755268 PMCID: PMC7907260 DOI: 10.1080/10253890.2020.1806226] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The diversity of actions of the glucocorticoid stress hormones among individuals and within organs, tissues and cells is shaped by age, gender, genetics, metabolism, and the quantity of exposure. However, such factors cannot explain the heterogeneity of responses in the brain within cells of the same lineage, or similar tissue environment, or in the same individual. Here, we argue that the stress response is continuously updated by synchronized neural activity on large-scale brain networks. This occurs at the molecular, cellular and behavioral levels by crosstalk communication between activity-dependent and glucocorticoid signaling pathways, which updates the diversity of responses based on prior experience. Such a Bayesian process determines adaptation to the demands of the body and external world. We propose a framework for understanding how the diversity of glucocorticoid actions throughout brain networks is essential for supporting optimal health, while its disruption may contribute to the pathophysiology of stress-related disorders, such as major depression, and resistance to therapeutic treatments.
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Affiliation(s)
- Damien HUZARD
- Department of Neuroscience and Physiology, University of Montpellier, CNRS, INSERM, Institut de Génomique Fonctionnelle, Montpellier, France
| | - Virginie RAPPENEAU
- Department of Behavioural Biology, University of Osnabrück, Osnabrück, Germany
| | - Onno C. MEIJER
- Division of Endocrinology, Department of Internal Medicine, Leiden University Medical Center, Leiden University, Leiden, the Netherlands
| | - Chadi TOUMA
- Department of Behavioural Biology, University of Osnabrück, Osnabrück, Germany
| | - Margarita ARANGO-LIEVANO
- Department of Neuroscience and Physiology, University of Montpellier, CNRS, INSERM, Institut de Génomique Fonctionnelle, Montpellier, France
| | | | - Freddy JEANNETEAU
- Department of Neuroscience and Physiology, University of Montpellier, CNRS, INSERM, Institut de Génomique Fonctionnelle, Montpellier, France
- Corresponding author:
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Rappeneau V, Wilmes L, Touma C. Molecular correlates of mitochondrial dysfunctions in major depression: Evidence from clinical and rodent studies. Mol Cell Neurosci 2020; 109:103555. [PMID: 32979495 DOI: 10.1016/j.mcn.2020.103555] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 08/24/2020] [Accepted: 09/03/2020] [Indexed: 12/13/2022] Open
Abstract
Major depressive disorder (MDD) is one of the most prevalent stress-related mental disorders worldwide. Several biological mechanisms underlying the pathophysiology of MDD have been proposed, including endocrine disturbances, neurotransmitter deficits, impaired neuronal plasticity, and more recently, mitochondrial dysfunctions. In this review, we provide an overview of relevant molecular correlates of mitochondrial dysfunction in MDD, based on findings from clinical studies and stress-induced rodent models. We also compare differences and similarities between the phenotypes of MDD patients and animal models. Our analysis of the literature reveals that both MDD and stress are associated, in humans and animals, with changes in mitochondrial biogenesis, redox imbalance, increased oxidative damages of cellular macromolecules, and apoptosis. Yet, a considerable amount of conflicting data exist and therefore, the translation of findings from clinical and preclinical research to novel therapies for MDD remains complex. Further studies are needed to advance our understanding of the molecular networks and biological mechanisms involving mitochondria in the pathophysiology of MDD.
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Affiliation(s)
- Virginie Rappeneau
- Department of Behavioural Biology, University of Osnabrück, Osnabrück, Germany.
| | - Lars Wilmes
- Department of Behavioural Biology, University of Osnabrück, Osnabrück, Germany
| | - Chadi Touma
- Department of Behavioural Biology, University of Osnabrück, Osnabrück, Germany
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Effects of Stathmin 1 Gene Knockout on Behaviors and Dopaminergic Markers in Mice Exposed to Social Defeat Stress. Brain Sci 2019; 9:brainsci9090215. [PMID: 31454951 PMCID: PMC6769668 DOI: 10.3390/brainsci9090215] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 08/19/2019] [Accepted: 08/23/2019] [Indexed: 01/08/2023] Open
Abstract
Stathmin (STMN), a microtubule-destabilizing factor, can regulate fear, anxiety, and learning. Social defeat stress (SDS) has detrimental effects on mental health and increases the risk of various psychiatric diseases. This study investigated the effects of STMN1 gene knockout (KO) on behavioral parameters and dopaminergic markers using an SDS mouse model. The STMN1 KO mice showed anxious hyperactivity, impaired object recognition, and decreased levels of neutral and social investigating behaviors at baseline compared to wild-type (WT) mice. The impact of SDS on neutral, social investigating and dominant behaviors differed markedly between the STMN1 WT and KO mice. In addition, different levels of total DARPP-32 and pDARPP-32 Thr75 expression were observed among the control, unsusceptible, and susceptible groups of STMN1 KO mice. Our results show that STMN1 has specific roles in locomotion, object recognition, and social interactions. Moreover, SDS had differential impacts on social interactions and dopaminergic markers between STMN1 WT and KO mice.
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Bonapersona V, Damsteegt R, Adams ML, van Weert LTCM, Meijer OC, Joëls M, Sarabdjitsingh RA. Sex-Dependent Modulation of Acute Stress Reactivity After Early Life Stress in Mice: Relevance of Mineralocorticoid Receptor Expression. Front Behav Neurosci 2019; 13:181. [PMID: 31440147 PMCID: PMC6693524 DOI: 10.3389/fnbeh.2019.00181] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 07/19/2019] [Indexed: 01/11/2023] Open
Abstract
Early life stress (ELS) is considered a major risk factor for developing psychopathology. Increasing evidence points towards sex-dependent dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis as a contributing mechanism. Additionally, clinical studies suggest that the mineralocorticoid receptor (MR) may further confer genetic vulnerability/resilience on a background of ELS. The link between ELS, sex and the HPA axis and how this interacts with MR genotype is understudied, yet important to understand vulnerability/resilience to stress. We used the early life-limited nesting and bedding model to test the effect of ELS on HPA properties in adult female and male mice carrying a forebrain-specific heterozygous knockout for MR. Basal HPA axis activity was measured by circadian peak and nadir corticosterone levels, in addition to body weight and weight of stress-sensitive tissues. HPA axis reactivity was assessed by mapping corticosterone levels after 10 min immobilization. Additionally, we measured the effects of ELS on steroid receptor [MR and glucocorticoid receptor (GR)] levels in the dorsal hippocampus and medial prefrontal cortex (mPFC) with western blot. Finally, behavioral reactivity towards a novel environment was measured as a proxy for anxiety-like behavior. Results show that HPA axis activity under rest conditions was not affected by ELS. HPA axis reactivity after immobilization was decreased by ELS in females and increased, at trend-level in males. This effect in females was further exacerbated by low expression of the MR. We also observed a sex*ELS interaction regarding MR and GR expression in the dorsal hippocampus, with a significant upregulation of MR in males only. The sex-dependent interaction with ELS was not reflected in the behavioral response to novel environment and time spent in a sheltered compartment. We did find increased locomotor activity in all groups after a history of ELS, which attenuated after 4 h in males but not females regardless of condition. Our findings support that ELS alters HPA axis functioning sex-dependently. Genetic predisposition to low MR function may render females more susceptible to the harmful effect of ELS whereas in males low MR function promotes resilience. We propose that this model may be a useful tool to investigate the underlying mechanisms of sex-dependent and genetic vulnerability/resilience to stress-related psychopathology.
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Affiliation(s)
- Valeria Bonapersona
- Department of Translational Neuroscience, UMC Utrecht Brain Center, Utrecht University, Utrecht, Netherlands
| | - Ruth Damsteegt
- Department of Translational Neuroscience, UMC Utrecht Brain Center, Utrecht University, Utrecht, Netherlands
| | - Mirjam L Adams
- Department of Translational Neuroscience, UMC Utrecht Brain Center, Utrecht University, Utrecht, Netherlands
| | - Lisa T C M van Weert
- Department of Internal Medicine, Leiden University Medical Center, Division of Endocrinology, Leiden, Netherlands
| | - Onno C Meijer
- Department of Internal Medicine, Leiden University Medical Center, Division of Endocrinology, Leiden, Netherlands
| | - Marian Joëls
- Department of Translational Neuroscience, UMC Utrecht Brain Center, Utrecht University, Utrecht, Netherlands.,University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Ratna Angela Sarabdjitsingh
- Department of Translational Neuroscience, UMC Utrecht Brain Center, Utrecht University, Utrecht, Netherlands
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Korucu CÇ, Atay İM, Zayıf SS, Gültekin F. May nesfatin-1 be a state marker in major depressive disorder with suicidal ideation? Psychiatry Res 2018; 267:272-276. [PMID: 29940459 DOI: 10.1016/j.psychres.2018.05.086] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 05/05/2018] [Accepted: 05/29/2018] [Indexed: 12/17/2022]
Abstract
The best known effects of nesfatin-1 are on appetite and metabolic regulation. Moreover, several research suggest that nesfatin-1 play a role in stress responses. This molecule may be involved in the pathophysiology of mood disorders and suicidal behavior. We compared nesfatin-1 levels between depressed patients with suicidal ideation (n = 32, mean ± SD, 1,40 ± 0.11), without suicidal ideation(n = 31, 1.46 ± 0.14) and healthy controls (n = 32, 1.52 ± 0.13). Suicidal ideation was assessed with the Suicide Probability Scale, Scale for Suicide Ideation and depressive symptoms were evaluated with the Hamilton Depression Rating Scale. Blood samples were collected to measure serum nesfatin-1levels by using ELISA method. The study revealed that serum nesfatin-1 levels were significantly lower in MDD with suicidal ideation than in healthy volunteers (p < 0.001). There were a negative correlation between the scores of suicidal ideation and nesfatin-1 levels in MDD with SI group (r = -0.215; p = 0.016). In the future, nesfatin-1 levels may one day be applied in predicting and monitoring patients' suicide risk. Further prospective studies are required to elucidate this potential association.
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Affiliation(s)
- Cafer Çağrı Korucu
- Department of Psychiatry, Usak University Education and Research Hospital, Usak, Turkey.
| | - İnci Meltem Atay
- Department of Psychiatry, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey
| | - Seden Sert Zayıf
- Department of Biochemistry, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey
| | - Fatih Gültekin
- Department of Biochemistry, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey
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Burns SB, Szyszkowicz JK, Luheshi GN, Lutz PE, Turecki G. Plasticity of the epigenome during early-life stress. Semin Cell Dev Biol 2018; 77:115-132. [DOI: 10.1016/j.semcdb.2017.09.033] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 09/08/2017] [Accepted: 09/22/2017] [Indexed: 12/22/2022]
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Barnett Burns S, Almeida D, Turecki G. The Epigenetics of Early Life Adversity: Current Limitations and Possible Solutions. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2018; 157:343-425. [DOI: 10.1016/bs.pmbts.2018.01.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Social Origins of Developmental Risk for Mental and Physical Illness. J Neurosci 2017; 37:10783-10791. [PMID: 29118206 DOI: 10.1523/jneurosci.1822-17.2017] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Revised: 10/03/2017] [Accepted: 10/10/2017] [Indexed: 12/19/2022] Open
Abstract
Adversity in early childhood exerts an enduring impact on mental and physical health, academic achievement, lifetime productivity, and the probability of interfacing with the criminal justice system. More science is needed to understand how the brain is affected by early life stress (ELS), which produces excessive activation of stress response systems broadly throughout the child's body (toxic stress). Our research examines the importance of sex, timing and type of stress exposure, and critical periods for intervention in various brain systems across species. Neglect (the absence of sensitive and responsive caregiving) or disrupted interaction with offspring induces robust, lasting consequences in mice, monkeys, and humans. Complementary assessment of internalizing disorders and brain imaging in children suggests that early adversity can interfere with white matter development in key brain regions, which may increase risk for emotional difficulties in the long term. Neural circuits that are most plastic during ELS exposure in monkeys sustain the greatest change in gene expression, offering a mechanism whereby stress timing might lead to markedly different long-term behaviors. Rodent models reveal that disrupted maternal-infant interactions yield metabolic and behavioral outcomes often differing by sex. Moreover, ELS may further accelerate or delay critical periods of development, which reflect GABA circuit maturation, BDNF, and circadian Clock genes. Such factors are associated with several mental disorders and may contribute to a premature closure of plastic windows for intervention following ELS. Together, complementary cross-species studies are elucidating principles of adaptation to adversity in early childhood with molecular, cellular, and whole organism resolution.
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