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Demaestri C, Gallo M, Mazenod E, Hong AT, Arora H, Short AK, Stern H, Baram TZ, Bath KG. Resource scarcity but not maternal separation provokes unpredictable maternal care sequences in mice and both upregulate Crh-associated gene expression in the amygdala. Neurobiol Stress 2022; 20:100484. [PMID: 36120094 PMCID: PMC9475315 DOI: 10.1016/j.ynstr.2022.100484] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/22/2022] [Accepted: 08/29/2022] [Indexed: 11/26/2022] Open
Abstract
Early life adversity (ELA) is a major risk factor for the development of pathology, including anxiety disorders. Neurodevelopmental and behavioral outcomes following ELA are multifaceted and are influenced heavily by the type of adversity experienced and sex of the individual experiencing ELA. It remains unclear what properties of ELA portend differential neurobiological risk and the basis of sex-differences for negative outcomes. Predictability of the postnatal environment has emerged as being a core feature supporting development, with the most salient signals deriving from parental care. Predictability of parental care may be a distinguishing feature of different forms of ELA, and the degree of predictability afforded by these manipulations may contribute to the diversity of outcomes observed across models. Further, questions remain as to whether differing levels of predictability may contribute to differential effects on neurodevelopment and expression of genes associated with risk for pathology. Here, we tested the hypothesis that changes in maternal behavior in mice would be contingent on the type of ELA experienced, directly comparing predictability of care in the limited bedding and nesting (LBN) and maternal separation (MS) paradigms. We then tested whether the predictability of the ELA environment altered the expression of corticotropin-releasing hormone (Crh), a sexually-dimorphic neuropeptide that regulates threat-related learning, in the amygdala of male and female mice. The LBN manipulation reliably increased the entropy of maternal care, a measure that indicates lower predictability between sequences of dam behavior. LBN and MS rearing similarly increased the frequency of nest sorties and licking of pups but had mixed effects on other aspects of dam-, pup-, and nest-related behaviors. Increased expression of Crh-related genes was observed in pups that experienced ELA, with gene expression measures showing a significant interaction with sex and type of ELA manipulation. Specifically, MS was associated with increased expression of Crh-related genes in males, but not females, and LBN primarily increased expression of these genes in females, but not males. The present study provides evidence for predictability as a distinguishing feature of models of ELA and demonstrates robust consequences of these differing experience on sex-differences in gene expression critically associated with stress responding and sex differences in risk for pathology.
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Affiliation(s)
- Camila Demaestri
- Doctoral Program in Neurobiology and Behavior, Columbia University, New York, NY, USA
| | - Meghan Gallo
- Doctoral Program in Cognitive, Linguistic and Psychological Sciences, Brown University, Providence, RI, USA
- Division of Developmental Neuroscience, Research Foundation for Mental Hygiene, Inc./ New York State Psychiatric Institute, New York, NY, USA
- Department of Psychiatry, Columbia University Irving Medical Center, New York, NY, USA
| | - Elisa Mazenod
- Doctoral Program in Cognitive, Linguistic and Psychological Sciences, Brown University, Providence, RI, USA
| | - Alexander T. Hong
- Department of Anatomy and Neurobiology, University of California-Irvine, Irvine, CA, USA
| | - Hina Arora
- Department of Statistics, University of California-Irvine, Irvine, CA, USA
| | - Annabel K. Short
- Department of Anatomy and Neurobiology, University of California-Irvine, Irvine, CA, USA
- Department of Pediatrics, University of California-Irvine, Irvine, CA, USA
| | - Hal Stern
- Department of Statistics, University of California-Irvine, Irvine, CA, USA
| | - Tallie Z. Baram
- Department of Anatomy and Neurobiology, University of California-Irvine, Irvine, CA, USA
- Department of Pediatrics, University of California-Irvine, Irvine, CA, USA
- Department of Neurology, University of California-Irvine, CA, USA
| | - Kevin G. Bath
- Division of Developmental Neuroscience, Research Foundation for Mental Hygiene, Inc./ New York State Psychiatric Institute, New York, NY, USA
- Department of Psychiatry, Columbia University Irving Medical Center, New York, NY, USA
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2
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Short AK, Thai CW, Chen Y, Kamei N, Pham AL, Birnie MT, Bolton JL, Mortazavi A, Baram TZ. Single-Cell Transcriptional Changes in Hypothalamic Corticotropin-Releasing Factor-Expressing Neurons After Early-Life Adversity Inform Enduring Alterations in Vulnerabilities to Stress. BIOLOGICAL PSYCHIATRY GLOBAL OPEN SCIENCE 2021; 3:99-109. [PMID: 36712559 PMCID: PMC9874075 DOI: 10.1016/j.bpsgos.2021.12.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/11/2021] [Accepted: 12/03/2021] [Indexed: 02/01/2023] Open
Abstract
Background Mental health and vulnerabilities to neuropsychiatric disorders involve the interplay of genes and environment, particularly during sensitive developmental periods. Early-life adversity (ELA) and stress promote vulnerabilities to stress-related affective disorders, yet it is unknown how transient ELA dictates lifelong neuroendocrine and behavioral reactions to stress. The population of hypothalamic corticotropin-releasing factor (CRF)-expressing neurons that regulate stress responses is a promising candidate to mediate the long-lasting influences of ELA on stress-related behavioral and hormonal responses via enduring transcriptional and epigenetic mechanisms. Methods Capitalizing on a well-characterized model of ELA, we examined ELA-induced changes in gene expression profiles of CRF-expressing neurons in the hypothalamic paraventricular nucleus of developing male mice. We used single-cell RNA sequencing on isolated CRF-expressing neurons. We determined the enduring functional consequences of transcriptional changes on stress reactivity in adult ELA mice, including hormonal responses to acute stress, adrenal weights as a measure of chronic stress, and behaviors in the looming shadow threat task. Results Single-cell transcriptomics identified distinct and novel CRF-expressing neuronal populations, characterized by both their gene expression repertoire and their neurotransmitter profiles. ELA-provoked expression changes were selective to specific subpopulations and affected genes involved in neuronal differentiation, synapse formation, energy metabolism, and cellular responses to stress and injury. Importantly, these expression changes were impactful, apparent from adrenal hypertrophy and augmented behavioral responses to stress in adulthood. Conclusions We uncover a novel repertoire of stress-regulating CRF cell types differentially affected by ELA and resulting in augmented stress vulnerability, with relevance to the origins of stress-related affective disorders.
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Affiliation(s)
- Annabel K. Short
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, California,Department of Pediatrics, University of California Irvine, Irvine, California
| | - Christina W. Thai
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, California
| | - Yuncai Chen
- Department of Pediatrics, University of California Irvine, Irvine, California
| | - Noriko Kamei
- Department of Pediatrics, University of California Irvine, Irvine, California
| | - Aidan L. Pham
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, California,Department of Pediatrics, University of California Irvine, Irvine, California
| | - Matthew T. Birnie
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, California,Department of Pediatrics, University of California Irvine, Irvine, California
| | - Jessica L. Bolton
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, California,Department of Pediatrics, University of California Irvine, Irvine, California
| | - Ali Mortazavi
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, California
| | - Tallie Z. Baram
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, California,Department of Pediatrics, University of California Irvine, Irvine, California,Department of Neurology, University of California Irvine, Irvine, California,Address correspondence to Tallie Z. Baram, M.D., Ph.D.
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Ramphal B, Pagliaccio D, Dworkin JD, Herbstman J, Noble KG, Margolis AE. Timing-specific associations between income-to-needs ratio and hippocampal and amygdala volumes in middle childhood: A preliminary study. Dev Psychobiol 2021; 63:e22153. [PMID: 34674248 DOI: 10.1002/dev.22153] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 05/28/2021] [Accepted: 06/04/2021] [Indexed: 01/23/2023]
Abstract
It is well known that financial disadvantage is associated with alterations in brain development in regions critical to socioemotional well-being such as the hippocampus and the amygdala. Yet little is known about whether family income at different points in development is differentially associated with these structures. Furthermore, little is known about which environmental factors statistically mediate associations between income and subcortical structure. Using a longitudinal birth cohort and linear mixed-effects models, we identified associations between income-to-needs ratio (INR) at 6 timepoints throughout childhood and hippocampal and amygdala volumes at age 7-9 years (n = 41; 236 INR measurements; 41 brain measurements). Mediation analysis identified environmental sequelae of income that statistically accounted for INR-brain associations. Lower INR prior to age 4 was associated with smaller hippocampal volumes, whereas lower INR prior to age 2 was associated with smaller right amygdala volume. These associations were mediated by unmet basic needs (e.g., food, housing). These findings delineate the temporal specificity of associations between income and hippocampal and amygdala structures.
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Affiliation(s)
- Bruce Ramphal
- New York State Psychiatric Institute and Department of Psychiatry, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - David Pagliaccio
- New York State Psychiatric Institute and Department of Psychiatry, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Jordan D Dworkin
- New York State Psychiatric Institute and Department of Psychiatry, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Julie Herbstman
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - Kimberly G Noble
- Department of Biobehavioral Sciences, Teachers College, Columbia University, New York, New York, USA
| | - Amy E Margolis
- New York State Psychiatric Institute and Department of Psychiatry, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
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Kooiker CL, Birnie MT, Baram TZ. The Paraventricular Thalamus: A Potential Sensor and Integrator of Emotionally Salient Early-Life Experiences. Front Behav Neurosci 2021; 15:673162. [PMID: 34079442 PMCID: PMC8166219 DOI: 10.3389/fnbeh.2021.673162] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 04/20/2021] [Indexed: 02/03/2023] Open
Abstract
Early-life experiences influence a broad spectrum of behaviors throughout the lifespan that contribute to resilience or vulnerability to mental health disorders. Yet, how emotionally salient experiences early in life are encoded, stored, and processed and the mechanisms by which they influence future behaviors remain poorly understood. The paraventricular nucleus of the thalamus (PVT) is a key structure in modulating positive and negative experiences and behaviors in adults. However, little is known of the PVT's role in encoding and integrating emotionally salient experiences that occur during neonatal, infancy, and childhood periods. In this review, we (1) describe the functions and connections of the PVT and its regulation of behavior, (2) introduce novel technical approaches to elucidating the role of the PVT in mediating enduring changes in adult behaviors resulting from early-life experiences, and (3) conclude that PVT neurons of neonatal rodents are engaged by both positive and negative emotionally salient experiences, and their activation may enduringly govern future behavior-modulating PVT activity during emotionally salient contexts.
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Affiliation(s)
- Cassandra L. Kooiker
- Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA, United States
| | - Matthew T. Birnie
- Department of Pediatrics, University of California, Irvine, Irvine, CA, United States
| | - Tallie Z. Baram
- Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA, United States
- Department of Pediatrics, University of California, Irvine, Irvine, CA, United States
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Benson MJ, Lauková M, Borges K, Velíšková J, Velíšek L. Prenatal betamethasone exposure increases corticotropin-releasing hormone expression along with increased hippocampal slice excitability in the developing hippocampus. Epilepsy Res 2020; 160:106276. [PMID: 31954921 DOI: 10.1016/j.eplepsyres.2020.106276] [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: 10/18/2019] [Revised: 12/31/2019] [Accepted: 01/14/2020] [Indexed: 01/12/2023]
Abstract
BACKGROUND The objective of this study was to determine whether prenatal exposure to betamethasone alters hippocampal expression of corticotropin-releasing hormone (CRH) and resultant hippocampal circuit excitability. METHODS Real time (RT)-PCR and western blots were used to determine CRH mRNA and protein expression levels, respectively, in hippocampal extracts of two-week old rat pups prenatally primed with betamethasone or saline on gestational day 15. The data were compared to changes in epileptiform activity induced by kainic acid (KA) or depletion of [Mg2+]0 in combined hippocampus-entorhinal cortex slices. RESULTS RT-PCR analysis showed 3-fold increased levels of CRH mRNA in hippocampal extracts from prenatally betamethasone-primed pups compared to saline controls (p < 0.05), but no changes in mRNA expression of CRH receptors (1 and 2). Changes in CRH protein isoform ratio in hippocampal extracts suggest 30 % increase in mature CRH levels in betamethasone-primed hippocampi (p < 0.05). No changes in mRNA expression in CRH feedback loop associated genes, GR and FKBP51, were found. Compared to saline-exposed pups, slices from betamethasone-primed pups had faster onset of epileptiform-like activity (inter-ictal discharges and seizure-like-events) after bath application of 4 μM KA (p < 0.05) suggesting a "more hyperexcitable" state. The epileptiform-like activity after KA application was significantly reduced following bath application of a CRH R2 antagonist (p < 0.05) but CRH R1 antagonist had no effect (p > 0.05). Also in the low-Mg2+-induced epileptiform activity, there was increased excitability, in the form of enhanced inter-ictal discharges, in slices from betamethasone primed compared to saline exposed rat pups (p < 0.05). CONCLUSIONS Our study suggests a possible mechanistic link to prenatal betamethasone priming-induced increase in postnatal hippocampal excitability that involves enhanced expression of CRH acting at CRH R2. This is important in regards to the links between prenatal stress/corticosteroid-exposure and syndromes, such as epilepsy, autism spectrum disorders and other psychiatric disorders associated with neuronal hyperexcitability.
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Affiliation(s)
- Melissa J Benson
- Departments of Cell Biology & Anatomy, Valhalla, NY, USA; Department of Pharmacology, School of Biomedical Sciences, University of Queensland, St Lucia, QLD, Australia
| | - Marcela Lauková
- Department of Environmental Health Science, School of Health Sciences and Practice, Institute of Public Health, New York Medical College, Valhalla, NY, USA; Institute of Experimental Endocrinology, Biomedical Research Center, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Karin Borges
- Department of Pharmacology, School of Biomedical Sciences, University of Queensland, St Lucia, QLD, Australia
| | - Jana Velíšková
- Departments of Cell Biology & Anatomy, Valhalla, NY, USA; Departments of Obstetrics & Gynecology, Valhalla, NY, USA; Departments of Neurology, Valhalla, NY, USA
| | - Libor Velíšek
- Departments of Cell Biology & Anatomy, Valhalla, NY, USA; Departments of Obstetrics & Gynecology, Valhalla, NY, USA; Departments of Pediatrics, New York Medical College, Valhalla, NY, USA.
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Heydari A, Esmaeilpour K, Sheibani V. Maternal separation impairs long term-potentiation in CA3-CA1 synapses in adolescent female rats. Behav Brain Res 2019; 376:112239. [PMID: 31526768 DOI: 10.1016/j.bbr.2019.112239] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/11/2019] [Accepted: 09/13/2019] [Indexed: 12/28/2022]
Abstract
Mother-infant interactions influence the development of physiology and behavior during the first weeks after birth. As an adverse early life experience, maternal separation (MS) produces behavioral and neuroendocrine functions disorders associated with the hippocampus. Considering the critical role of long-term potentiation (LTP) in learning and memory, we investigated whether MS affects LTP in adolescent female rats. In this study, female rat pups were exposed to daily 3-h (MS180) or 15-min (MS15) periods of maternal separation on postnatal days (PND) 1-14 and control offspring remained with the dams all the time before weaning. Extracellular evoked field excitatory postsynaptic potentials (fEPSPs) were recorded in the stratum radiatum of the CA1 area of the slice at 28-35 days of age. Our results indicate that a significant difference existed in the magnitude of LTP between the control group and MS180 group, but the MS15 group was not different from control. In conclusion, these findings suggest that MS may impair LTP induction in the CA1 area of the hippocampus in adolescent female rats.
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Affiliation(s)
- Arefe Heydari
- Department of Physiology, Faculty of Medicine, Kerman university of Medical Sciences, Kerman, Iran
| | - Khadijeh Esmaeilpour
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.
| | - Vahid Sheibani
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran; Department of Physiology, Faculty of Medicine, Kerman university of Medical Sciences, Kerman, Iran.
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7
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Working memory moderates the association between early institutional care and separation anxiety symptoms in late childhood and adolescence. Dev Psychopathol 2019; 31:989-997. [PMID: 31038094 DOI: 10.1017/s0954579419000452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Adverse caregiving, for example, previous institutionalization (PI), is often associated with emotion dysregulation that increases anxiety risk. However, the concept of developmental multifinality predicts heterogeneity in anxiety outcomes. Despite this well-known heterogeneity, more work is needed to identify sources of this heterogeneity and how these sources interact with environmental risk to influence mental health. Here, working memory (WM) was examined during late childhood/adolescence as an intra-individual factor to mitigate the risk for separation anxiety, which is particularly susceptible to caregiving adversities. A modified "object-in-place" task was administered to 110 youths (10-17 years old), with or without a history of PI. The PI youths had elevated separation anxiety scores, which were anticorrelated with morning cortisol levels, yet there were no group differences in WM. PI youths showed significant heterogeneity in separation anxiety symptoms and morning cortisol levels, and WM moderated the link between caregiving and separation anxiety and mediated the association between separation anxiety and morning cortisol in PI youth. Findings suggest that (a) institutional care exerts divergent developmental consequences on separation anxiety versus WM, (b) WM interacts with adversity-related emotion dysregulation, and (c) WM may be a therapeutic target for separation anxiety following early caregiving adversity.
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Bolton JL, Short AK, Simeone KA, Daglian J, Baram TZ. Programming of Stress-Sensitive Neurons and Circuits by Early-Life Experiences. Front Behav Neurosci 2019; 13:30. [PMID: 30833892 PMCID: PMC6387907 DOI: 10.3389/fnbeh.2019.00030] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 02/04/2019] [Indexed: 12/22/2022] Open
Abstract
Early-life experiences influence brain structure and function long-term, contributing to resilience or vulnerability to stress and stress-related disorders. Therefore, understanding the mechanisms by which early-life experiences program specific brain cells and circuits to shape life-long cognitive and emotional functions is crucial. We identify the population of corticotropin-releasing hormone (CRH)-expressing neurons in the hypothalamic paraventricular nucleus (PVN) as a key, early target of early-life experiences. Adverse experiences increase excitatory neurotransmission onto PVN CRH cells, whereas optimal experiences, such as augmented and predictable maternal care, reduce the number and function of glutamatergic inputs onto this cell population. Altered synaptic neurotransmission is sufficient to initiate large-scale, enduring epigenetic re-programming within CRH-expressing neurons, associated with stress resilience and additional cognitive and emotional outcomes. Thus, the mechanisms by which early-life experiences influence the brain provide tractable targets for intervention.
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Affiliation(s)
- Jessica L Bolton
- Departments of Pediatrics, Anatomy/Neurobiology, Neurology, University of California, Irvine, Irvine, CA, United States
| | - Annabel Katherine Short
- Departments of Pediatrics, Anatomy/Neurobiology, Neurology, University of California, Irvine, Irvine, CA, United States
| | - Kristina A Simeone
- Departments of Pediatrics, Anatomy/Neurobiology, Neurology, University of California, Irvine, Irvine, CA, United States
| | - Jennifer Daglian
- Departments of Pediatrics, Anatomy/Neurobiology, Neurology, University of California, Irvine, Irvine, CA, United States
| | - Tallie Z Baram
- Departments of Pediatrics, Anatomy/Neurobiology, Neurology, University of California, Irvine, Irvine, CA, United States
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Vangopoulou C, Bourmpoula MT, Koupourtidou C, Giompres P, Stamatakis A, Kouvelas ED, Mitsacos A. Effects of an early life experience on rat brain cannabinoid receptors in adolescence and adulthood. IBRO Rep 2018; 5:1-9. [PMID: 30135950 PMCID: PMC6095101 DOI: 10.1016/j.ibror.2018.05.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 05/14/2018] [Accepted: 05/26/2018] [Indexed: 12/17/2022] Open
Abstract
Neonatal handling is an experimental model of early life experience associated with resilience in later life challenges, altering the ability of animals to respond to stress. The endocannabinoid system of the brain modulates the neuroendocrine and behavioral effects of stress, while this system is also capable of being modulated by stress exposure itself. The present study has addressed the question of whether neonatal handling in rats could affect cannabinoid receptors, in an age- and sex-dependent manner, using in situ hybridization and receptor binding techniques. Different effects of neonatal handling were observed in adolescent and adult brain on CB1 receptor mRNA and [3H]CP55,940 binding levels, which in some cases were sexually dimorphic. Neonatal handling interfered in the developmental trajectories of CB1 receptor mRNA levels in striatum and amygdaloid nuclei, as well as of [3H]CP55,940 binding levels in almost all regions studied. Adult handled rats showed reduced [3H]CP55,940 binding levels in the prefrontal cortex, striatum, nucleus accumbens and basolateral amygdala, while binding levels in prefrontal cortex of adolescent handled rats were increased. Finally, handling resulted in decreases in female [3H]CP55,940 binding levels in the striatum, nucleus accumbens, CA3 and DG of dorsal hippocampus and basolateral amygdala. Our results suggest that a brief and repeated maternal separation during the neonatal period induces changes on cannabinoid receptors differently manifested between adolescence and adulthood, male and female brain, which could be correlated to their stress response.
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Key Words
- 2-AG, 2-arachidonoylglycerol
- ANOVA, analysis of variance
- Adolescence
- BLA, basolateral nucleus of amygdala
- BSA, bovine serum albumin
- CA1, dorsal field 1 of Ammon’s horn
- CA3, dorsal field 3 of Ammon’s horn
- CB1 cannabinoid receptors
- CB1, cannabinoid receptor 1
- CPu-DL, dorsolateral striatum
- CPu-VM, ventromedial striatum
- CeA, central amygdaloid nucleus
- Cg1, anterior cingulate cortex
- DG, dentate gyrus
- Female rat brain
- GR, glucocorticoid receptors
- GrDG, dentate gyrus granule cell layer
- HPA, hypothalamic-pituitary-adrenal
- IL, infralimbic cortex
- LTD, long-term depression
- MO, medial orbital cortex
- Male rat brain
- Maternal separation
- MoDG, dentate gyrus molecular layer
- NAc, nucleus accumbens
- NS, not significant
- Neonatal handling
- PFC, prefrontal cortex
- PND, postnatal day
- PrL, prelimbic cortex
- ROD, relative optical density
- RT, room temperature
- eCB, endocannabinoid
- mPFC, medial prefrontal cortex
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Affiliation(s)
- Chara Vangopoulou
- Laboratory of Physiology, Medical School, University of Patras, 26500, Patras, Greece
| | - Maria T. Bourmpoula
- Laboratory of Physiology, Medical School, University of Patras, 26500, Patras, Greece
| | | | - Panagiotis Giompres
- Laboratory of Human and Animal Physiology, Department of Biology, University of Patras, 265040, Patras, Greece
| | - Antonios Stamatakis
- Laboratory of Biology-Biochemistry, Faculty of Nursing, University of Athens, 11527, Athens, Greece
| | - Elias D. Kouvelas
- Laboratory of Physiology, Medical School, University of Patras, 26500, Patras, Greece
| | - Ada Mitsacos
- Laboratory of Physiology, Medical School, University of Patras, 26500, Patras, Greece
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Abstract
The hypothalamic-pituitary-adrenal (HPA) axis is the major neuroendocrine axis regulating homeostasis in mammals. Glucocorticoid hormones are rapidly synthesized and secreted from the adrenal gland in response to stress. In addition, under basal conditions glucocorticoids are released rhythmically with both a circadian and an ultradian (pulsatile) pattern. These rhythms are important not only for normal function of glucocorticoid target organs, but also for the HPA axis responses to stress. Several studies have shown that disruption of glucocorticoid rhythms is associated with disease both in humans and in rodents. In this review, we will discuss our knowledge of the negative feedback mechanisms that regulate basal ultradian synthesis and secretion of glucocorticoids, including the role of glucocorticoid and mineralocorticoid receptors and their chaperone protein FKBP51. Moreover, in light of recent findings, we will also discuss the importance of intra-adrenal glucocorticoid receptor signaling in regulating glucocorticoid synthesis.
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Affiliation(s)
- Julia K Gjerstad
- Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Stafford L Lightman
- Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Francesca Spiga
- Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
- CONTACT Francesca SpigaUniversity of Bristol, Translational Health Sciences, Bristol Medical School, Dorothy Hodgkin Building, Whitson Street, BristolBS1 3NY, UK
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11
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Bolton JL, Molet J, Regev L, Chen Y, Rismanchi N, Haddad E, Yang DZ, Obenaus A, Baram TZ. Anhedonia Following Early-Life Adversity Involves Aberrant Interaction of Reward and Anxiety Circuits and Is Reversed by Partial Silencing of Amygdala Corticotropin-Releasing Hormone Gene. Biol Psychiatry 2018; 83:137-147. [PMID: 29033027 PMCID: PMC5723546 DOI: 10.1016/j.biopsych.2017.08.023] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 08/29/2017] [Accepted: 08/29/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND Anhedonia, the diminished ability to experience pleasure, is an important dimensional entity linked to depression, schizophrenia, and other emotional disorders, but its origins and mechanisms are poorly understood. We have previously identified anhedonia, manifest as decreased sucrose preference and social play, in adolescent male rats that experienced chronic early-life adversity/stress (CES). Here we probed the molecular, cellular, and circuit processes underlying CES-induced anhedonia and tested them mechanistically. METHODS We examined functional brain circuits and neuronal populations activated by social play in adolescent CES and control rats. Structural connectivity between stress- and reward-related networks was probed using high-resolution diffusion tensor imaging, and cellular/regional activation was probed using c-Fos. We employed viral-genetic approaches to reduce corticotropin-releasing hormone (Crh) expression in the central nucleus of the amygdala in anhedonic rats, and tested for anhedonia reversal in the same animals. RESULTS Sucrose preference was reduced in adolescent CES rats. Social play, generally considered an independent measure of pleasure, activated brain regions involved in reward circuitry in both control and CES groups. In CES rats, social play activated Crh-expressing neurons in the central nucleus of the amygdala, typically involved in anxiety/fear, indicating aberrant functional connectivity of pleasure/reward and fear circuits. Diffusion tensor imaging tractography revealed increased structural connectivity of the amygdala to the medial prefrontal cortex in CES rats. Crh-short hairpin RNA, but not control short hairpin RNA, given into the central nucleus of the amygdala reversed CES-induced anhedonia without influencing other emotional measures. CONCLUSIONS These findings robustly demonstrate aberrant interactions of stress and reward networks after early-life adversity and suggest mechanistic roles for Crh-expressing amygdala neurons in emotional deficits portending major neuropsychiatric disorders.
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Affiliation(s)
- Jessica L. Bolton
- Department of Anatomy/Neurobiology, University of California- Irvine,Department of Pediatrics, University of California- Irvine
| | - Jenny Molet
- Department of Anatomy/Neurobiology, University of California- Irvine,Department of Pediatrics, University of California- Irvine
| | - Limor Regev
- Department of Pediatrics, University of California- Irvine
| | - Yuncai Chen
- Department of Pediatrics, University of California- Irvine
| | - Neggy Rismanchi
- Department of Anatomy/Neurobiology, University of California- Irvine
| | | | - Derek Z. Yang
- Department of Anatomy/Neurobiology, University of California- Irvine
| | - Andre Obenaus
- Department of Pediatrics, University of California- Irvine
| | - Tallie Z. Baram
- Department of Anatomy/Neurobiology, University of California- Irvine,Department of Pediatrics, University of California- Irvine,Corresponding Author: Tallie Z. Baram, MD, PhD, Pediatrics and Anatomy/Neurobiology, University of California-Irvine, Medical Sciences I, ZOT: 4475, Irvine, CA 92697-4475, USA, Tel: 949.824.6478; Fax: 949.824.1106;
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12
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Diz-Chaves Y, Gil-Lozano M, Toba L, Fandiño J, Ogando H, González-Matías LC, Mallo F. Stressing diabetes? The hidden links between insulinotropic peptides and the HPA axis. J Endocrinol 2016; 230:R77-94. [PMID: 27325244 DOI: 10.1530/joe-16-0118] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 06/20/2016] [Indexed: 12/25/2022]
Abstract
Diabetes mellitus exerts metabolic stress on cells and it provokes a chronic increase in the long-term activity of the hypothalamus-pituitary-adrenocortical (HPA) axis, perhaps thereby contributing to insulin resistance. GLP-1 receptor (GLP-1R) agonists are pleiotropic hormones that not only affect glycaemic and metabolic control, but they also produce many other effects including activation of the HPA axis. In fact, several of the most relevant effects of GLP-1 might involve, at least in part, the modulation of the HPA axis. Thus, the anorectic activity of GLP-1 could be mediated by increasing CRF at the hypothalamic level, while its lipolytic effects could imply a local increase in glucocorticoids and glucocorticoid receptor (GC-R) expression in adipose tissue. Indeed, the potent activation of the HPA axis by GLP-1R agonists occurs within the range of therapeutic doses and with a short latency. Interestingly, the interactions of GLP-1 with the HPA axis may underlie most of the effects of GLP-1 on food intake control, glycaemic metabolism, adipose tissue biology and the responses to stress. Moreover, such activity has been observed in animal models (mice and rats), as well as in normal humans and in type I or type II diabetic patients. Accordingly, better understanding of how GLP-1R agonists modulate the activity of the HPA axis in diabetic subjects, especially obese individuals, will be crucial to design new and more efficient therapies for these patients.
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Affiliation(s)
- Yolanda Diz-Chaves
- Laboratory of EndocrinologyCenter for Biomedical Research - CINBIO, University of Vigo, Vigo, Spain Instituto de Investigación Sanitaria Galicia Sur - IISGSVigo, Spain
| | - Manuel Gil-Lozano
- Laboratory of EndocrinologyCenter for Biomedical Research - CINBIO, University of Vigo, Vigo, Spain Instituto de Investigación Sanitaria Galicia Sur - IISGSVigo, Spain
| | - Laura Toba
- Laboratory of EndocrinologyCenter for Biomedical Research - CINBIO, University of Vigo, Vigo, Spain Instituto de Investigación Sanitaria Galicia Sur - IISGSVigo, Spain
| | - Juan Fandiño
- Laboratory of EndocrinologyCenter for Biomedical Research - CINBIO, University of Vigo, Vigo, Spain Instituto de Investigación Sanitaria Galicia Sur - IISGSVigo, Spain
| | - Hugo Ogando
- Laboratory of EndocrinologyCenter for Biomedical Research - CINBIO, University of Vigo, Vigo, Spain Instituto de Investigación Sanitaria Galicia Sur - IISGSVigo, Spain
| | - Lucas C González-Matías
- Laboratory of EndocrinologyCenter for Biomedical Research - CINBIO, University of Vigo, Vigo, Spain Instituto de Investigación Sanitaria Galicia Sur - IISGSVigo, Spain
| | - Federico Mallo
- Laboratory of EndocrinologyCenter for Biomedical Research - CINBIO, University of Vigo, Vigo, Spain Instituto de Investigación Sanitaria Galicia Sur - IISGSVigo, Spain
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13
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Abstract
The endocrine hypothalamus constitutes those cells which project to the median eminence and secrete neurohormones into the hypophysial portal blood to act on cells of the anterior pituitary gland. The entire endocrine system is controlled by these peptides. In turn, the hypothalamic neuroendocrine cells are regulated by feedback signals from the endocrine glands and other circulating factors. The neuroendocrine cells are found in specific regions of the hypothalamus and are regulated by afferents from higher brain centers. Integrated function is clearly complex and the networks between and amongst the neuroendocrine cells allows fine control to achieve homeostasis. The entry of hormones and other factors into the brain, either via the cerebrospinal fluid or through fenestrated capillaries (in the basal hypothalamus) is important because it influences the extent to which feedback regulation may be imposed. Recent evidence of the passage of factors from the pars tuberalis and the median eminence casts a new layer in our understanding of neuroendocrine regulation. The function of neuroendocrine cells and the means by which pulsatile secretion is achieved is best understood for the close relationship between gonadotropin releasing hormone and luteinizing hormone, which is reviewed in detail. The secretion of other neurohormones is less rigid, so the relationship between hypothalamic secretion and the relevant pituitary hormones is more complex.
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Affiliation(s)
- I J Clarke
- Monash University, Department of Physiology, Clayton, Australia
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14
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Uchoa ET, Aguilera G, Herman JP, Fiedler JL, Deak T, Cordeiro de Sousa MB. Novel aspects of glucocorticoid actions. J Neuroendocrinol 2014; 26:557-72. [PMID: 24724595 PMCID: PMC4161987 DOI: 10.1111/jne.12157] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 04/06/2014] [Accepted: 04/08/2014] [Indexed: 12/20/2022]
Abstract
Normal hypothalamic-pituitary-adrenal (HPA) axis activity leading to the rhythmic and episodic release of adrenal glucocorticoids (GCs) is essential for body homeostasis and survival during stress. Acting through specific intracellular receptors in the brain and periphery, GCs regulate behaviour, as well as metabolic, cardiovascular, immune and neuroendocrine activities. By contrast to chronic elevated levels, circadian and acute stress-induced increases in GCs are necessary for hippocampal neuronal survival and memory acquisition and consolidation, as a result of the inhibition of apoptosis, the facilitation of glutamatergic neurotransmission and the formation of excitatory synapses, and the induction of immediate early genes and dendritic spine formation. In addition to metabolic actions leading to increased energy availability, GCs have profound effects on feeding behaviour, mainly via the modulation of orexigenic and anorixegenic neuropeptides. Evidence is also emerging that, in addition to the recognised immune suppressive actions of GCs by counteracting adrenergic pro-inflammatory actions, circadian elevations have priming effects in the immune system, potentiating acute defensive responses. In addition, negative-feedback by GCs involves multiple mechanisms leading to limited HPA axis activation and prevention of the deleterious effects of excessive GC production. Adequate GC secretion to meet body demands is tightly regulated by a complex neural circuitry controlling hypothalamic corticotrophin-releasing hormone (CRH) and vasopressin secretion, which are the main regulators of pituitary adrenocorticotrophic hormone (ACTH). Rapid feedback mechanisms, likely involving nongenomic actions of GCs, mediate the immediate inhibition of hypothalamic CRH and ACTH secretion, whereas intermediate and delayed mechanisms mediated by genomic actions involve the modulation of limbic circuitry and peripheral metabolic messengers. Consistent with their key adaptive roles, HPA axis components are evolutionarily conserved, being present in the earliest vertebrates. An understanding of these basic mechanisms may lead to novel approaches for the development of diagnostic and therapeutic tools for disorders related to stress and alterations of GC secretion.
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Affiliation(s)
- Ernane Torres Uchoa
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Greti Aguilera
- Section on Endocrine Physiology, National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - James P. Herman
- Department of Psychiatry and Behavioural Neuroscience, University of Cincinnati, Metabolic Diseases Institute, Cincinnati, OH, USA
| | - Jenny L. Fiedler
- Department of Biochemistry and Molecular Biology, Faculty of Chemical and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - Terrence Deak
- Department of Psychology, Binghamton University, Binghamton, NY, USA
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15
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Raineki C, Lucion AB, Weinberg J. Neonatal handling: an overview of the positive and negative effects. Dev Psychobiol 2014; 56:1613-25. [PMID: 25132525 DOI: 10.1002/dev.21241] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 06/24/2014] [Indexed: 02/06/2023]
Abstract
As one of the first rodent models designed to investigate the effects of early-life experiences, the neonatal handling paradigm has helped us better understand how subtle changes in the infant environment can powerfully drive neurodevelopment of the immature brain in typical or atypical trajectories. Here, we review data from more than 50 years demonstrating the compelling effects of neonatal handling on behavior, physiology, and neural function across the lifespan. Moreover, we present data that challenge the classical view of neonatal handling as an animal model that results only in positive/beneficial outcomes. Indeed, the overall goal of this review is to offer the suggestion that the effects of early-life experiences-including neonatal handling-are nuanced rather than unidirectional. Both beneficial and negative outcomes may occur, depending on the parameters of testing, sex of the subject, and neurobehavioral system analyzed.
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Affiliation(s)
- Charlis Raineki
- Department of Cellular and Physiological Sciences, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, Canada, V6T 1Z3.
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16
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Tottenham N. The importance of early experiences for neuro-affective development. Curr Top Behav Neurosci 2014; 16:109-29. [PMID: 24264369 DOI: 10.1007/7854_2013_254] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This chapter considers the functional utility of the prolonged period of immaturity in human brain development. Development of the amygdala and its connections with the prefrontal cortex is used as an example system for discussing the special role of sensitive periods in shaping neural functional architecture. The argument is made that neural immaturity during childhood may be important and confer a longer period of neuroplasticity, which can increase learning from the environment.
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Affiliation(s)
- Nim Tottenham
- University of California, Franz Hall, Psychology Department, 502 Portola Plaza, Los Angeles, CA, 90095, USA,
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17
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Cope JL, Regev L, Chen Y, Korosi A, Rice CJ, Ji S, Rogge GA, Wood MA, Baram TZ. Differential contribution of CBP:CREB binding to corticotropin-releasing hormone expression in the infant and adult hypothalamus. Stress 2014; 17:39-50. [PMID: 23768074 PMCID: PMC3869921 DOI: 10.3109/10253890.2013.806907] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Corticotropin-releasing hormone (CRH) contributes crucially to the regulation of central and peripheral responses to stress. Because of the importance of a finely tuned stress system, CRH expression is tightly regulated in an organ- and brain region-specific manner. Thus, in the hypothalamus, CRH is constitutively expressed and this expression is further enhanced by stress; however, the underlying regulatory mechanisms are not fully understood. The regulatory region of the crh gene contains several elements, including the cyclic-AMP response element (CRE), and the role of the CRE interaction with the cyclic-AMP response element binding protein (CREB) in CRH expression has been a focus of intensive research. Notably, whereas thousands of genes contain a CRE, the functional regulation of gene expression by the CRE:CREB system is limited to ∼100 genes, and likely requires additional proteins. Here, we investigated the role of a member of the CREB complex, CREB binding protein (CBP), in basal and stress-induced CRH expression during development and in the adult. Using mice with a deficient CREB-binding site on CBP, we found that CBP:CREB interaction is necessary for normal basal CRH expression at the mRNA and protein level in the nine-day-old mouse, prior to onset of functional regulation of hypothalamic CRH expression by glucocorticoids. This interaction, which functions directly on crh or indirectly via regulation of other genes, was no longer required for maintenance of basal CRH expression levels in the adult. However, CBP:CREB binding contributed to stress-induced CRH expression in the adult, enabling rapid CRH synthesis in hypothalamus. CBP:CREB binding deficiency did not disrupt basal corticosterone plasma levels or acute stress-evoked corticosterone release. Because dysregulation of CRH expression occurs in stress-related disorders including depression, a full understanding of the complex regulation of this gene is important in both health and disease.
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Affiliation(s)
- Jessica L. Cope
- Department of Anatomy and Neurobiology, University of California-Irvine, Irvine, CA 92697, USA
| | - Limor Regev
- Department of Anatomy and Neurobiology, University of California-Irvine, Irvine, CA 92697, USA
| | - Yuncai Chen
- Department of Pediatrics, University of California-Irvine, Irvine, CA 92697, USA
| | - Aniko Korosi
- Department of Anatomy and Neurobiology, University of California-Irvine, Irvine, CA 92697, USA
| | - Courtney J. Rice
- Department of Anatomy and Neurobiology, University of California-Irvine, Irvine, CA 92697, USA
| | - Sung Ji
- Department of Anatomy and Neurobiology, University of California-Irvine, Irvine, CA 92697, USA
| | - George A. Rogge
- Department of Neurobiology and Behavior, University of California-Irvine, Irvine, CA 92697, USA
| | - Marcelo A. Wood
- Department of Neurobiology and Behavior, University of California-Irvine, Irvine, CA 92697, USA
| | - Tallie Z. Baram
- Department of Anatomy and Neurobiology, University of California-Irvine, Irvine, CA 92697, USA
- Department of Pediatrics, University of California-Irvine, Irvine, CA 92697, USA
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18
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Evans AN, Liu Y, Macgregor R, Huang V, Aguilera G. Regulation of hypothalamic corticotropin-releasing hormone transcription by elevated glucocorticoids. Mol Endocrinol 2013; 27:1796-807. [PMID: 24065704 DOI: 10.1210/me.2013-1095] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Negative glucocorticoid feedback is essential for preventing the deleterious effects of excessive hypothalamic pituitary adrenal axis axis activation, with an important target being CRH transcription in the hypothalamic paraventricular nucleus. The aim of these studies was to determine whether glucocorticoids repress CRH transcription directly in CRH neurons, by examining glucocorticoid effects on glucocorticoid receptor (GR)-CRH promoter interaction and the activation of proteins required for CRH transcription. Immunoprecipitation of hypothalamic chromatin from intact or adrenalectomized rats subjected to either stress or corticosterone injections showed minor association of the proximal CRH promoter with the GR compared with that with phospho-CREB (pCREB). In contrast, the Period-1 (Per1, a glucocorticoid-responsive gene) promoter markedly recruited GR. Stress increased pCREB recruitment by the CRH but not the Per1 promoter, irrespective of circulating glucocorticoids. In vitro, corticosterone pretreatment (30 minutes or 18 hours) only slightly inhibited basal and forskolin-stimulated CRH heteronuclear RNA in primary hypothalamic neuronal cultures and CRH promoter activity in hypothalamic 4B cells. In 4B cells, 30 minutes or 18 hours of corticosterone exposure had no effect on forskolin-induced nuclear accumulation of the recognized CRH transcriptional regulators, pCREB and transducer of regulated CREB activity 2. The data show that inhibition of CRH transcription by physiological glucocorticoids in vitro is minor and that direct interaction of GR with DNA in the proximal CRH promoter may not be a major mechanism of CRH gene repression. Although GR interaction with distal promoter elements may have a role, the data suggest that transcriptional repression of CRH by glucocorticoids involves protein-protein interactions and/or modulation of afferent inputs to the hypothalamic paraventricular nucleus.
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Affiliation(s)
- Andrew N Evans
- Section on Endocrine Physiology, Eunice Kennedy Shriver Institute of Child Health and Human Development, National Institutes of Health, Building 10/CRC, Room 1E-3330, Bethesda, Maryland 20892.
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19
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Hostetler CM, Ryabinin AE. The CRF system and social behavior: a review. Front Neurosci 2013; 7:92. [PMID: 23754975 PMCID: PMC3668170 DOI: 10.3389/fnins.2013.00092] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Accepted: 05/14/2013] [Indexed: 01/10/2023] Open
Abstract
The corticotropin-releasing factor (CRF) system plays a key role in a diversity of behaviors accompanying stress, anxiety and depression. There is also substantial research on relationships between social behaviors and the CRF system in a variety of taxa including fish, birds, rodents, and primates. Some of these relationships are due to the broad role of CRF and urocortins in stress and anxiety, but these peptides also modulate social behavior specifically. For example, the social interaction (SI) test is often used to measure anxiety-like behavior. Many components of the CRF system including CRF, urocortin1, and the R1 receptor have been implicated in SI, via general effects on anxiety as well as specific effects depending on the brain region. The CRF system is also highly responsive to chronic social stressors such as social defeat and isolation. Animals exposed to these stressors display a number of anxiety- and stress-related behaviors, accompanied by changes in specific components the CRF system. Although the primary focus of CRF research on social behavior has been on the deleterious effects of social stress, there are also insights on a role for CRF and urocortins in prosocial and affiliative behaviors. The CRF system has been implicated in parental care, maternal defense, sexual behavior, and pair bonding. Species differences in the ligands and CRF receptors have been observed in vole and bird species differing in social behavior. Exogenous administration of CRF facilitates partner preference formation in monogamous male prairie voles, and these effects are dependent on both the CRF R1 and R2 receptors. These findings are particularly interesting as studies have also implicated the CRF and urocortins in social memory. With the rapid progress of social neuroscience and in understanding the complex structure of the CRF system, the next challenge is in parsing the exact contribution of individual components of this system to specific social behaviors.
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Affiliation(s)
- Caroline M Hostetler
- Department of Behavioral Neuroscience, Oregon Health and Science University Portland, OR, USA
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20
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Goncharova ND. Stress responsiveness of the hypothalamic-pituitary-adrenal axis: age-related features of the vasopressinergic regulation. Front Endocrinol (Lausanne) 2013; 4:26. [PMID: 23486926 PMCID: PMC3594837 DOI: 10.3389/fendo.2013.00026] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2012] [Accepted: 02/22/2013] [Indexed: 12/22/2022] Open
Abstract
The hypothalamic-pituitary-adrenal (HPA) axis plays a key role in adaptation to environmental stresses. Parvicellular neurons of the hypothalamic paraventricular nucleus secrete corticotrophin releasing hormone (CRH) and arginine vasopressin (AVP) into pituitary portal system; CRH and AVP stimulate adrenocorticotropic hormone (ACTH) release through specific G-protein-coupled membrane receptors on pituitary corticotrophs, CRHR1 for CRH and V1b for AVP; the adrenal gland cortex secretes glucocorticoids in response to ACTH. The glucocorticoids activate specific receptors in brain and peripheral tissues thereby triggering the necessary metabolic, immune, neuromodulatory, and behavioral changes to resist stress. While importance of CRH, as a key hypothalamic factor of HPA axis regulation in basal and stress conditions in most species, is generally recognized, role of AVP remains to be clarified. This review focuses on the role of AVP in the regulation of stress responsiveness of the HPA axis with emphasis on the effects of aging on vasopressinergic regulation of HPA axis stress responsiveness. Under most of the known stressors, AVP is necessary for acute ACTH secretion but in a context-specific manner. The current data on the AVP role in regulation of HPA responsiveness to chronic stress in adulthood are rather contradictory. The importance of the vasopressinergic regulation of the HPA stress responsiveness is greatest during fetal development, in neonatal period, and in the lactating adult. Aging associated with increased variability in several parameters of HPA function including basal state, responsiveness to stressors, and special testing. Reports on the possible role of the AVP/V1b receptor system in the increase of HPA axis hyperactivity with aging are contradictory and requires further research. Many contradictory results may be due to age and species differences in the HPA function of rodents and primates.
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Affiliation(s)
- Nadezhda D. Goncharova
- Research Institute of Medical Primatology of Russian Academy of Medical SciencesSochi, Russia
- Sochi State UniversitySochi, Russia
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21
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Tottenham N. Human amygdala development in the absence of species-expected caregiving. Dev Psychobiol 2012; 54:598-611. [PMID: 22714586 DOI: 10.1002/dev.20531] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Accepted: 01/07/2011] [Indexed: 11/10/2022]
Abstract
In altricial species, like the human, caregiver presence is necessary for typical emotional development. Children who have been raised in institutional care early in life experience caregiver deprivation and are at significantly elevated risk for emotional difficulties. The current manuscript examines the non-human and human literatures on amygdala development following caregiver deprivation and presents an argument that in the absence of the species-expected caregiver presence, human amygdala development exhibits rapid development and perhaps premature engagement that results in some of the emotional phenotypes observed following early institutional care.
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Affiliation(s)
- Nim Tottenham
- Department of Psychology, University of California, Los Angeles, PO Box 951563, Los Angeles, CA 90095, USA.
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22
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Aguilera G, Liu Y. The molecular physiology of CRH neurons. Front Neuroendocrinol 2012; 33:67-84. [PMID: 21871477 PMCID: PMC4341841 DOI: 10.1016/j.yfrne.2011.08.002] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2011] [Revised: 07/31/2011] [Accepted: 08/02/2011] [Indexed: 01/14/2023]
Abstract
Corticotropin releasing hormone (CRH) is essential for stress adaptation by mediating hypothalamic-pituitary-adrenal (HPA) axis, behavioral and autonomic responses to stress. Activation of CRH neurons depends on neural afferents from the brain stem and limbic system, leading to sequential CRH release and synthesis. CRH transcription is required to restore mRNA and peptide levels, but termination of the response is essential to prevent pathology associated with chronic elevations of CRH and HPA axis activity. Inhibitory feedback mediated by glucocorticoids and intracellular production of the repressor, Inducible Cyclic AMP Early Repressor (ICER), limit the magnitude and duration of CRH neuronal activation. Induction of CRH transcription is mediated by the cyclic AMP/protein kinase A/cyclic AMP responsive element binding protein (CREB)-dependent pathways, and requires cyclic AMP-dependent nuclear translocation of the CREB co-activator, Transducer of Regulated CREB activity (TORC). This article reviews current knowledge on the mechanisms regulating CRH neuron activity.
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Affiliation(s)
- Greti Aguilera
- Section on Endocrine Physiology, Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shiver Institute of Child Health and Human Development, NIH, Bethesda, MD 20892, United States.
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23
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Regulatory functions of limbic Y1 receptors in body weight and anxiety uncovered by conditional knockout and maternal care. Proc Natl Acad Sci U S A 2011; 108:19395-400. [PMID: 22084082 DOI: 10.1073/pnas.1109468108] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Neuropeptide Y (NPY) plays an important role in stress, anxiety, obesity, and energy homeostasis via activation of NPY-Y1 receptors (Y1Rs) in the brain. However, global knockout of the Npy1r gene has low or no impact on anxiety and body weight. To uncover the role of limbic Y1Rs, we generated conditional knockout mice in which the inactivation of the Npy1r gene was restricted to excitatory neurons of the forebrain, starting from juvenile stages (Npy1r(rfb)). Npy1r(rfb) mice exhibited increased anxiety and reduced body weight, less adipose tissue, and lower serum leptin levels. Npy1r(rfb) mutants also had a hyperactive hypothalamic-pituitary-adrenocortical axis, as indicated by higher peripheral corticosterone and higher density of NPY immunoreactive fibers and corticotropin releasing hormone immunoreactive cell bodies in the paraventricular hypothalamic nucleus. Importantly, through fostering experiments, we determined that differences in phenotype between Npy1r(rfb) and Npy1r(2lox) mice became apparent when both genotypes were raised by FVB/J but not by C57BL/6J dams, suggesting that limbic Y1Rs are key targets of maternal care-induced programming of anxiety and energy homeostasis.
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24
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Badowska-Szalewska E, Spodnik E, Ludkiewicz B, Klejbor I, Moryś J. Nerve growth factor (NGF) immunoreactive neurons in the juvenile rat hippocampus: response to acute and long-term high-light open-field (HL-OF) or forced swim (FS) stress stimulation. Neuroscience 2011; 199:491-500. [PMID: 22027234 DOI: 10.1016/j.neuroscience.2011.10.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 09/13/2011] [Accepted: 10/09/2011] [Indexed: 12/30/2022]
Abstract
This study aimed at examining and comparing the influence of two different stress stimuli on the density (number of cells/mm²) of nerve growth factor (NGF) containing neurons in the hippocampal CA1 and CA3 pyramidal cell layers and the dentate gyrus (DG) granule cell layer in juvenile rats (P28; P-postnatal day). The high-light open-field (HL-OF) test and forced swim (FS) test were employed to investigate the effects of a single, 15-min acute exposure and repeated (15 min daily for 21 days) long-term exposure to stress. In order to detect NGF-ir neurons, immunohistochemical (-ir) techniques were used. In comparison with nonstressed animals, acute and long-term HL-OF or FS stimulation resulted in a marked increase (P<0.001) in the density of NGF-ir containing cells in all the hippocampal structures. The frequency of stress application (acute vs. long-term), however, did not have a substantial impact on the studied parameter, with the exception of the CA3 sector, where a decreased density (P<0.001) of NGF-ir neurons was observed after long-term exposure to FS. It may be concluded that a rise in the density of NGF-ir neurons in the juvenile rat hippocampus after exposure to HL-OF or FS stressors could have affected the activity of the hypothalamic-pituitary-adrenocortical (HPA) stress axis. Prolonged HL-OF or FS stress was probably aggravating enough not to trigger the habituation process. The type of stressor applied (HL-OF vs. FS) was not essentially a factor determining the density of NGF-ir cells in the hippocampus.
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Affiliation(s)
- E Badowska-Szalewska
- Department of Anatomy and Neurobiology, Medical University of Gdańsk, Dębinki 1 Street, 80-211 Gdańsk, Poland.
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25
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Silveira PP, Portella AK, da Silva Benetti C, Zugno AI, da Silva Scherer EB, Mattos CB, Wyse ATS, Lucion AB, Dalmaz C. Association Between Na+,K+-ATPase Activity and the Vulnerability/Resilience to Mood Disorders induced by Early Life Experience. Neurochem Res 2011; 36:2075-82. [DOI: 10.1007/s11064-011-0531-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 06/07/2011] [Indexed: 10/18/2022]
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26
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Schulkin J. Evolutionary conservation of glucocorticoids and corticotropin releasing hormone: Behavioral and physiological adaptations. Brain Res 2011; 1392:27-46. [DOI: 10.1016/j.brainres.2011.03.055] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 03/14/2011] [Accepted: 03/22/2011] [Indexed: 02/05/2023]
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27
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Aguilera G. HPA axis responsiveness to stress: implications for healthy aging. Exp Gerontol 2011; 46:90-5. [PMID: 20833240 PMCID: PMC3026863 DOI: 10.1016/j.exger.2010.08.023] [Citation(s) in RCA: 157] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 08/19/2010] [Accepted: 08/27/2010] [Indexed: 02/06/2023]
Abstract
The major neuroendocrine response mediating stress adaptation is activation of the hypothalamic pituitary adrenal axis, with stimulation of corticotropin releasing hormone (CRH) and vasopressin (VP) from parvocellular neurons of the hypothalamic paraventricular nucleus, leading to stimulation of pituitary ACTH secretion and increases in glucocorticoid secretion from the adrenal cortex. Basal production and transient increases during stress of glucocorticoids and its hypothalamic regulators are essential for neuronal plasticity and normal brain function. While activation of the HPA axis is essential for survival during stress, chronic exposure to stress hormones can predispose to psychological, metabolic and immune alterations. Thus, prompt termination of the stress response is essential to prevent negative effects of inappropriate levels of CRH and glucocorticoids. This review addresses the regulation of HPA axis activity with emphasis on the mechanisms of termination of CRH transcription, which is a critical step in this process. In addition, the actions by which glucocorticoids, CRH and VP can affect the aging process will be discussed.
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Affiliation(s)
- Greti Aguilera
- Section on Endocrine Physiology, Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shiver Institute of Child Health and Human Development, NIH, Bethesda, MD 20892, USA.
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Borelli KG, Defensor EB, Blanchard DC, Blanchard RJ, Griebel G. Effects of intra-hippocampal injections of the NK2 receptor antagonist saredutant on the elevated plus maze, and the mouse defense test battery. Neurosci Lett 2010; 485:241-5. [DOI: 10.1016/j.neulet.2010.09.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2010] [Revised: 08/30/2010] [Accepted: 09/05/2010] [Indexed: 11/24/2022]
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Heinrichs SC. Neurobehavioral consequences of stressor exposure in rodent models of epilepsy. Prog Neuropsychopharmacol Biol Psychiatry 2010; 34:808-15. [PMID: 19913590 DOI: 10.1016/j.pnpbp.2009.11.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 10/22/2009] [Accepted: 11/03/2009] [Indexed: 12/20/2022]
Abstract
Both normal, non-epileptic as well as seizure-prone rodents exhibit a spectrum of anxiogenic-like behaviors in response to stressor exposure. Comparative analysis reveals that the same set of emotionality dependent measures is sensitive to both stress reactivity in normal rodents as well as stress hyperreactivity typically seen in seizure-prone rodents. A variety of unconditioned, exploratory tasks reflect global sensitivity to stressor exposure in the form of behavioral inhibition of locomotor output. Moreover, well chosen stressors can trigger de novo seizures with or without a history of seizure incidence. Seizures may be elicited in response to stressful environmental stimuli such as noxious noises, tail suspension handling, or home cage disturbance. Stress reactivity studies in rodents with a genetic predisposition to seizures have yielded important clues regarding brain substrates that mediate seizure ontogeny and modulate ictogenesis. Brains of seizure susceptible rodents reflect elevated content of the stress-related neuropeptide, corticotropin-releasing factor (CRF) in several nuclei relative to non-susceptible controls and neutralization of brain CRF attenuates seizure sensitivity. Findings outlined in this review support a diathesis-stress hypothesis in which behavioral- and neuro-pathologies of genetically seizure susceptible rodents arise in part due to multifaceted hyperreactivity to noxious environmental stimuli.
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Affiliation(s)
- Stephen C Heinrichs
- Regis College, Psychology Department, Science Building 103, 235 Wellesley Street, Weston, MA 02493, United States.
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30
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Krishnan B, Centeno M, Pollandt S, Fu Y, Genzer K, Liu J, Gallagher JP, Shinnick-Gallagher P. Dopamine receptor mechanisms mediate corticotropin-releasing factor-induced long-term potentiation in the rat amygdala following cocaine withdrawal. Eur J Neurosci 2010; 31:1027-42. [PMID: 20377617 DOI: 10.1111/j.1460-9568.2010.07148.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Corticotropin-releasing factor (CRF) in the amygdala is involved in stress responses. Moreover, dopaminergic neurotransmission in the brain reward system including the amygdala plays a significant role in the pathology of cocaine addiction. The present study analysed CRF-induced synaptic plasticity, its pharmacological sensitivity and interactions with the dopamine (DA) system in the basolateral to lateral capsula central amygdala (lcCeA) pathway after a 2-week withdrawal from repeated cocaine administration. A physiologically relevant CRF concentration (25 nm) induced long-term potentiation (LTP) that was enhanced after cocaine withdrawal. In saline-treated rats, CRF-induced LTP was mediated through N-methyl-d-aspartate (NMDA) receptors, L-type voltage-gated calcium channels (L-VGCCs) and CRF(1) receptors. However, in cocaine-withdrawn animals, activation of CRF(1) and CRF(2) receptors was found to enhance LTP. This enhanced CRF-induced LTP after cocaine withdrawal was mediated through endogenous activation of both D1- and D2-like receptors. Furthermore, expression of the D1 receptor (D1R) but not the D2R, D3R, D4R or D5R was significantly increased after cocaine withdrawal. CRF(1) but not CRF(2) protein expression was increased, suggesting that elevated levels of these proteins contributed to the enhancement of CRF-induced LTP during cocaine withdrawal. CRF interactions with the DA system in the amygdala may represent a fundamental neurochemical and cellular mechanism linking stress to cocaine-induced neuronal plasticity.
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Affiliation(s)
- Balaji Krishnan
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, USA.
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31
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Tottenham N, Sheridan MA. A review of adversity, the amygdala and the hippocampus: a consideration of developmental timing. Front Hum Neurosci 2010; 3:68. [PMID: 20161700 PMCID: PMC2813726 DOI: 10.3389/neuro.09.068.2009] [Citation(s) in RCA: 286] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Accepted: 12/08/2009] [Indexed: 11/13/2022] Open
Abstract
A review of the human developmental neuroimaging literature that investigates outcomes following exposure to psychosocial adversity is presented with a focus on two subcortical structures – the hippocampus and the amygdala. Throughout this review, we discuss how a consideration of developmental timing of adverse experiences and age at measurement might provide insight into the seemingly discrepant findings across studies. We use findings from animal studies to suggest some mechanisms through which timing of experiences may result in differences across time and studies. The literature suggests that early life may be a time of heightened susceptibility to environmental stressors, but that expression of these effects will vary by age at measurement.
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Affiliation(s)
- Nim Tottenham
- University of California, Los Angeles Los Angeles, CA, USA
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32
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Faturi CB, Tiba PA, Kawakami SE, Catallani B, Kerstens M, Suchecki D. Disruptions of the mother-infant relationship and stress-related behaviours: altered corticosterone secretion does not explain everything. Neurosci Biobehav Rev 2009; 34:821-34. [PMID: 19751762 DOI: 10.1016/j.neubiorev.2009.09.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Revised: 08/19/2009] [Accepted: 09/05/2009] [Indexed: 01/15/2023]
Abstract
The hypothalamic-pituitary-adrenal (HPA) axis is the main neuroendocrine system of response to stress, and an imbalance of this system's activity is believed to be at the core of numerous psychiatric pathologies. During the neonatal period, the glucocorticoid response to stress is maintained at low levels by specific maternal behaviours, which is essential for proper brain development. Effective evaluation of the impact of increased secretion of corticosterone during an essentially anabolic developmental period on adulthood behaviour involved separation of the neonate from its mother for periods ranging from 3 to 24h. It has been shown that disinhibition of the stress response is achieved by such procedures. The pioneering studies by Seymour Levine set the stage for a prolific and promising field of study that may help neuroscientists unveil the neurobiological underpinnings of stress-related disorders. Based on a series of studies, we propose that maternal separation and maternal deprivation change stress-related behaviours, but that corticosterone seem to be only partially involved in these changes in adulthood. It appears that extra-hypothalamic corticotrophin-releasing factor and neurotransmitter systems may be the primary mediators of these behavioural outcomes.
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Moriceau S, Raineki C, Holman JD, Holman JG, Sullivan RM. Enduring neurobehavioral effects of early life trauma mediated through learning and corticosterone suppression. Front Behav Neurosci 2009; 3:22. [PMID: 19750195 PMCID: PMC2741290 DOI: 10.3389/neuro.08.022.2009] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Accepted: 08/11/2009] [Indexed: 12/03/2022] Open
Abstract
Early life trauma alters later life emotions, including fear. To better understand mediating mechanisms, we subjected pups to either predictable or unpredictable trauma, in the form of paired or unpaired odor-0.5 mA shock conditioning which, during a sensitive period, produces an odor preference and no learning respectively. Fear conditioning and its neural correlates were then assessed after the sensitive period at postnatal day (PN)13 or in adulthood, ages when amygdala-dependent fear occurs. Our results revealed that paired odor-shock conditioning starting during the sensitive period (PN8–12) blocked fear conditioning in older infants (PN13) and pups continued to express olfactory bulb-dependent odor preference learning. This PN13 fear learning inhibition was also associated with suppression of shock-induced corticosterone, although the age appropriate amygdala-dependent fear learning was reinstated with systemic corticosterone (3 mg/kg) during conditioning. On the other hand, sensitive period odor-shock conditioning did not prevent adult fear conditioning, although freezing, amygdala and hippocampal 2-DG uptake and corticosterone levels were attenuated compared to adult conditioning without infant conditioning. Normal levels of freezing, amygdala and hippocampal 2-DG uptake were induced with systemic corticosterone (5 mg/kg) during adult conditioning. These results suggest that the contingency of early life trauma mediates at least some effects of early life stress through learning and suppression of corticosterone levels. However, developmental differences between infants and adults are expressed with PN13 infants' learning consistent with the original learned preference, while adult conditioning overrides the original learned preference with attenuated amygdala-dependent fear learning.
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Affiliation(s)
- Stephanie Moriceau
- Emotional Brain Institute, The Nathan S. Kline Institute for Psychiatric Research Orangeburg, SC, USA.
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34
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Korosi A, Baram TZ. The central corticotropin releasing factor system during development and adulthood. Eur J Pharmacol 2008; 583:204-14. [PMID: 18275957 DOI: 10.1016/j.ejphar.2007.11.066] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2007] [Revised: 08/28/2007] [Accepted: 11/07/2007] [Indexed: 11/18/2022]
Abstract
Corticotropin releasing factor (CRH) has been shown to contribute critically to molecular and neuroendocrine responses to stress during both adulthood and development. This peptide and its receptors are expressed in the hypothalamus, as well as in limbic brain areas including amygdala and hippocampus. This is consistent with roles for CRH in mediating the influence of stress on emotional behavior and cognitive function. The expression of CRH and of its receptors in hypothalamus, amygdala and hippocampus is age-dependent, and is modulated by stress throughout life (including the first postnatal weeks). Uniquely during development, the cardinal influence of maternal care on the central stress response governs the levels of central CRH expression, and may alter the 'set-point' of CRH-gene sensitivity to stress in a lasting manner.
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Affiliation(s)
- Aniko Korosi
- Department of Anatomy, University of California Irvine, Irvine, CA 92697-4475, USA
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Korbey SM, Heinrichs SC, Leussis MP. Seizure susceptibility and locus ceruleus activation are reduced following environmental enrichment in an animal model of epilepsy. Epilepsy Behav 2008; 12:30-8. [PMID: 17983840 DOI: 10.1016/j.yebeh.2007.09.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Revised: 09/12/2007] [Accepted: 09/14/2007] [Indexed: 11/28/2022]
Abstract
Alterations in the complexity of social and physical housing environments modulate seizure susceptibility in animal models of epilepsy. The studies described here tested the hypothesis that environmental enrichment would delay seizure onset in the epileptic (El) mouse. Neural activation measured via cFos expression, accumulation of the stress neuropeptide corticotropin-releasing factor (CRF), and behavioral seizure susceptibility were quantified in El mice to better understand the mechanisms of ictogenesis. Enrichment housing of El mice from Postnatal Days 21 to 49 produced a 100% decrease in seizure susceptibility relative to El controls. cFos expression increased in the primary motor cortex, locus ceruleus, and hippocampus of El mice relative to ddY controls, an effect attenuated by enrichment housing. CRF levels were elevated by enrichment in the hippocampus of ddY mice only. This study provides evidence that enrichment housing delays the onset of seizure susceptibility in El mice while altering the neuronal and stress-related responses in seizure-associated regions of the El brain.
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Affiliation(s)
- Samantha M Korbey
- Department of Psychology, Boston College, 140 Commonwealth Avenue, Chestnut Hill, MA 02467, USA
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36
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Winkelmann-Duarte EC, Todeschin AS, Fernandes MC, Bittencourt LC, Pereira GAM, Samios VN, Schuh AFS, Achaval ME, Xavier LL, Sanvitto GL, Mandarim-de-Lacerda CA, Lucion AB. Plastic changes induced by neonatal handling in the hypothalamus of female rats. Brain Res 2007; 1170:20-30. [PMID: 17692831 DOI: 10.1016/j.brainres.2007.07.030] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2007] [Revised: 07/04/2007] [Accepted: 07/12/2007] [Indexed: 10/23/2022]
Abstract
Early-life events can exert profound long-lasting effects on several behaviors such as fear/anxiety, sexual activity, stress responses and reproductive functions. Present study aimed to examine the effects of neonatal handling on the volume and number of cells in the hypothalamic paraventricular nucleus (pPVN, parvocellular and mPVN, magnocellular regions) and the supraoptic nucleus (SON) in female rats at 11 and 90 days of age. Moreover, in the same areas, immunohistochemistry for oxytocin (OT) and glial fibrillary acidic protein (GFAP) were analyzed in the adult animals. Daily handling during the first 10 postnatal days reduced the number of cells in the pPVN and SON at both the 11 and 90 days. Handling decreased the number of OT-positive parvocellular cells in the PVN in adult females. No significant differences were detected on the optical density (OD) of GFAP-positive cells between the handled and nonhandled adult females. The effect of handling on cell loss was observed 24 h after the 10-day handling period and persisted into adulthood, indicating a stable morphological trace. Results suggest that neonatal handling can induce plastic changes in the central nervous system.
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Affiliation(s)
- Elisa C Winkelmann-Duarte
- Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Sarmento Leite 500, Porto Alegre, RS 90050-170, Brazil
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37
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Aguilera G, Kiss A, Liu Y, Kamitakahara A. Negative regulation of corticotropin releasing factor expression and limitation of stress response. Stress 2007; 10:153-61. [PMID: 17514584 DOI: 10.1080/10253890701391192] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Corticotropin releasing factor (CRF) coordinates behavioral, autonomic and hormonal responses to stress. Activation of the hypothalamic pituitary adrenal (HPA) axis with stimulation of CRF and vasopressin (VP) release from hypothalamic parvocellular neurons, and consequent secretion of ACTH from the anterior pituitary and glucocorticoid from the adrenal cortex, is the major endocrine response to stress. Current evidence indicates that the main regulator of ACTH secretion in acute and chronic conditions is CRF, in spite of the fact that the selective increases in expression of parvocellular VP and pituitary VP V1b receptors observed during prolonged activation of the HPA axis have suggested that VP becomes the predominant regulator. Following CRF release, activation of CRF transcription is required to restore mRNA and peptide levels, but termination of the response is essential to prevent pathology associated with chronic elevation of CRF and glucocorticoid production. While glucocorticoid feedback plays an important role in regulating CRF expression, the relative importance of direct transcriptional repression of the CRF gene by glucocorticoids in the overall feedback mechanism is not clear. In addition to glucocorticoids, intracellular feedback mechanisms in the CRF neuron, involving induction of repressor forms of cAMP response element modulator (CREM) limit CRF transcriptional responses by competing with the positive regulator, phospho-CREB. Rapid repression of CRF transcription following stress-induced activation is likely to contribute to limiting the stress response and to preventing disorders associated with excessive CRF production.
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Affiliation(s)
- Greti Aguilera
- Section on Endocrine Physiology, Developmental Endocrinology Branch, National Institute of Child Health and Human Development, NIH, Bethesda, MD 20892-1103, USA.
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38
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Michel GF, Tyler AN. Can knowledge of developmental processes illuminate the evolution of parental care? Dev Psychobiol 2007; 49:33-44. [PMID: 17186511 DOI: 10.1002/dev.20195] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
There are two levels of investigation for elucidating the evolution of parental behavior. The macro level focuses on how parental behavior can evolve as an aspect of reproduction. The micro level focuses on how species variations in parental behavior evolve. Recently, modern evolutionary biology has turned to developmental biology as a source for information about how trait variability (the substrate upon which natural selection and other evolutionary mechanisms can operate) can emerge during development (called "evo-devo"). Application of this evo-devo approach to the phenomenon of parental behavior requires identification of those mechanisms that produce variations in developmental pathways leading to parental behavior. It is these variations that provide the phenotypes for the potential evolution of different parental behavior systems. Variations in rodent maternal behavior affect the development of the HPA and HPG axes in their offspring. These mechanisms are examined to reveal how such developmental variations could underlie the evolution of biparental behavior. Knowledge of the developmental mechanisms responsible for species variations in mammalian parental behavior systems may provide insight into those mechanisms that may have been involved in the evolution of parental behavior itself.
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Affiliation(s)
- George F Michel
- Psychology Department, P.O. Box 26170, University of North Carolina at Greensboro, Greensboro, NC 27402-6170, USA.
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Giachino C, Canalia N, Capone F, Fasolo A, Alleva E, Riva MA, Cirulli F, Peretto P. Maternal deprivation and early handling affect density of calcium binding protein-containing neurons in selected brain regions and emotional behavior in periadolescent rats. Neuroscience 2007; 145:568-78. [PMID: 17275195 DOI: 10.1016/j.neuroscience.2006.12.042] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2006] [Revised: 11/15/2006] [Accepted: 12/08/2006] [Indexed: 12/16/2022]
Abstract
Adverse early life experiences can induce neurochemical changes that may underlie modifications in hypothalamic-pituitary-adrenal axis responsiveness, emotionality and cognition. Here, we investigated the expression of the calcium binding proteins (CBPs) calretinin, calbindin and parvalbumin, which identify subpopulations of GABAergic neurons and serve important functional roles by buffering intracellular calcium levels, following brief (early handling) and long (maternal deprivation) periods of maternal separation, as compared with non-handled controls. CBP-expressing neurons were analyzed in brain regions related to stress and anxiety. Emotionality was assessed in parallel using the social interaction test. Analyses were carried out at periadolescence, an important phase for the development of brain areas involved in stress responses. Our results indicate that density of CBP-immunoreactive neurons decreases in the paraventricular region of deprived rats but increases in the hippocampus and lateral amygdala of both early-handled and deprived rats when compared with controls. Emotionality is reduced in both early-handled and deprived animals. In conclusion, early handling and deprivation led to neurochemical and behavioral changes linked to stress-sensitive brain regions. These data suggest that the effects of early experiences on CBP containing neurons might contribute to the functional changes of neuronal circuits involved in emotional response.
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Affiliation(s)
- C Giachino
- Department of Animal and Human Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin, Italy
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40
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Forcelli PA, Orefice LL, Heinrichs SC. Neural, endocrine and electroencephalographic hyperreactivity to human contact: a diathesis-stress model of seizure susceptibility in El mice. Brain Res 2007; 1144:248-56. [PMID: 17320061 DOI: 10.1016/j.brainres.2007.01.100] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Revised: 11/11/2006] [Accepted: 01/25/2007] [Indexed: 11/22/2022]
Abstract
The El mouse strain provides a non-induced model of idiopathic, multifactorial epilepsy in which seizures are elicited in response to stressful environmental stimuli such as tail suspension handling. In the present studies, genetically seizure susceptible El and non-susceptible ddY control mice were exposed to tail suspension, foot-shock and social stressors in order to test the hypothesis that neural and physiological responses to such stimuli would be exaggerated in the El strain. The first experiment assessed neural cell density, stress neuropeptide (corticotropin releasing factor--CRF) levels, and plasma corticosterone activation in El and ddY mice in an unhandled control condition or following exposure to tail suspension or foot-shock stressors. The second experiment assessed brain electroencephalographic activity using telemetrically monitored skull surface electrodes in El and ddY mice exposed to tail suspension or social interaction stressors. Assessment of El mouse brains revealed higher cell counts in amygdala and elevated CRF peptide content in the paraventricular thalamic nucleus relative to ddY controls. El mice exhibited significantly elevated plasma corticosterone levels 60 min following exposure to tail suspension and foot-shock stressors relative to ddY controls. Finally, El mice exhibited significantly elevated brain electroencephalographic (1-4 Hz) activity in response to tail suspension, but not social interaction, relative to ddY controls. These results indicate that potentiated neural, endocrine and physiological activation arises in the El strain following exposure to a known seizure trigger stimulus, involuntary tail suspension handling. The findings support a diathesis-stress hypothesis in which genetically seizure susceptible El mice exhibit a multifaceted hyperreactivity to noxious environmental stimuli.
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Affiliation(s)
- Patrick A Forcelli
- Department of Psychology, Boston College, 140 Commonwealth Avenue, Chestnut Hill, MA 02467, USA
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41
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Knuth ED, Etgen AM. Long-term behavioral consequences of brief, repeated neonatal isolation. Brain Res 2006; 1128:139-47. [PMID: 17125746 PMCID: PMC1805632 DOI: 10.1016/j.brainres.2006.10.054] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Revised: 10/12/2006] [Accepted: 10/18/2006] [Indexed: 10/23/2022]
Abstract
Rats subjected to stressful stimuli during the stress hyporesponsive period exhibit varied neuroendocrine and behavioral changes as neonates, adolescents and adults. The current work examined the effects of neonatal isolation stress, using a within-litter design, on adult anxiety-related behavior and endocrine stress reactivity. Neonatal rats were isolated daily for 1 h from postnatal day (P) 4 to 9, a manipulation previously shown to induce hypothalamic-pituitary-adrenal (HPA) responses on P9 (Knuth, E.D., Etgen, A.M. (2005) Corticosterone secretion induced by chronic isolation in neonatal rats is sexually dimorphic and accompanied by elevated ACTH. Horm Behav 47:65-75.). Control animals were either handled briefly or left undisturbed (with-dam). Adult rats were tested for anxiety-related behavior using the elevated plus maze and open field, and for endocrine responses following restraint stress. Neonatal isolation decreased center exploration of the open field following 1 h restraint, including decreased time in the center compared to with-dam or handled controls and decreased center entries and distance traveled in the center compared to with-dam controls. It also decreased time in and entries into the open arms of the elevated plus maze compared to handled controls, suggesting enhanced anxiety-related behavior. Neonatal isolation had no effect on basal or restraint-induced levels of ACTH or corticosterone. These findings indicate that neonatal isolation may enhance anxiety-related behaviors, especially in response to stress, without altering HPA function.
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Affiliation(s)
- Emily D Knuth
- Department of Neuroscience, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Forchheimer 113, Bronx, NY 10461, USA
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42
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Fenoglio KA, Brunson KL, Baram TZ. Hippocampal neuroplasticity induced by early-life stress: functional and molecular aspects. Front Neuroendocrinol 2006; 27:180-92. [PMID: 16603235 PMCID: PMC2937188 DOI: 10.1016/j.yfrne.2006.02.001] [Citation(s) in RCA: 159] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2005] [Revised: 02/11/2006] [Accepted: 02/13/2006] [Indexed: 12/16/2022]
Abstract
Whereas genetic factors contribute crucially to brain function, early-life events, including stress, exert long-lasting influence on neuronal function. Here, we focus on the hippocampus as the target of these early-life events because of its crucial role in learning and memory. Using a novel immature-rodent model, we describe the deleterious consequences of chronic early-life 'psychological' stress on hippocampus-dependent cognitive tasks. We review the cellular mechanisms involved and discuss the roles of stress-mediating molecules, including corticotropin releasing hormone, in the process by which stress impacts the structure and function of hippocampal neurons.
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Affiliation(s)
- Kristina A. Fenoglio
- Department of Anatomy/Neurobiology, University of California at Irvine, Irvine, CA 92697-4475, USA
| | - Kristen L. Brunson
- Department of Anatomy/Neurobiology, University of California at Irvine, Irvine, CA 92697-4475, USA
| | - Tallie Z. Baram
- Department of Anatomy/Neurobiology, University of California at Irvine, Irvine, CA 92697-4475, USA
- Department of Pediatrics, University of California at Irvine, Irvine, CA 92697-4475, USA
- Corresponding author. Fax: +1 949 824 1106. (T.Z. Baram)
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43
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Fenoglio KA, Chen Y, Baram TZ. Neuroplasticity of the hypothalamic-pituitary-adrenal axis early in life requires recurrent recruitment of stress-regulating brain regions. J Neurosci 2006; 26:2434-42. [PMID: 16510721 PMCID: PMC2408688 DOI: 10.1523/jneurosci.4080-05.2006] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
An eloquent example of experience-induced neuroplasticity involves the enduring effects of daily "handling" of rat pups on the expression of genes regulating hormonal and behavioral responses to stress. Handling-evoked augmentation of maternal care of pups induces long-lasting reduction of hypothalamic corticotropin releasing hormone (CRH) expression and upregulates hippocampal glucocorticoid receptor levels. These changes promote a lifelong attenuation of hormonal stress responses. We have found previously that handling-evoked downregulation of CRH expression occurs already by postnatal day 9, implicating it as an early step in this experience-induced neuroplasticity. Here, we investigated the neuronal pathways and cellular mechanisms involved. CRH mRNA expression in hypothalamic paraventricular nucleus (PVN) diminished after daily handling but not after handling once only, indicating that "recurrent" handling was required for this effect. Return of handled pups to their cage provoked a burst of nurturing behavior in dams that, in turn, induced transient, coordinate Fos expression in selected regions of the pups' brains. These included central nucleus of the amygdala (ACe) and bed nucleus of the stria terminals (BnST), regions that are afferent to PVN and influence CRH expression there. Whereas handling once sufficed to evoke Fos expression within ACe and BnST, expression in thalamic paraventricular nucleus, a region involved in storing and processing stress-related experience, required recurrent handling. Fos induction in all three regions elicited reduced transcription factor phosphorylation, followed by attenuated activation of CRH gene transcription within the PVN. These studies provide a neurobiological foundation for the profound neuroplasticity of stress-related genes evoked by early-life experience.
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Warnock G, Prickaerts J, Steckler T. Interactions between CRF and acetylcholine in the modulation of cognitive behaviour. EXS 2006; 98:41-63. [PMID: 17019882 DOI: 10.1007/978-3-7643-7772-4_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Affiliation(s)
- Geoff Warnock
- Dept. Psychiatry, RED Europe, Johnson and Johnson Pharmaceutical Research and Development, Turnhoutseweg 30, 2340 Beerse, Belgium.
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Plotsky PM, Thrivikraman KV, Nemeroff CB, Caldji C, Sharma S, Meaney MJ. Long-term consequences of neonatal rearing on central corticotropin-releasing factor systems in adult male rat offspring. Neuropsychopharmacology 2005; 30:2192-204. [PMID: 15920504 DOI: 10.1038/sj.npp.1300769] [Citation(s) in RCA: 370] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In a series of studies on the long-term consequences of neonatal rearing, we compared hypothalamic and extrahypothalamic central corticotropin-releasing factor (CRF) systems in male rats reared under conditions of animal facility rearing, nonhandling (HMS0), handling with brief maternal separation for 15 min (HMS15), or handling with moderate maternal separation for 180 min (HMS180) daily from postnatal days 2-14. CRF-like immunoreactivity (CRFir) was elevated in lumbar cerebrospinal fluid of adult HMS180 and HMS0 rats relative to the other groups. In the paraventricular nucleus, central nucleus of the amygdala, bed nucleus of the stria terminalis, and locus coeruleus, CRFir and CRF mRNA levels were significantly elevated in HMS0 and HMS180 rats. Neonatal maternal separation was associated with regionally specific alterations in CRF receptor type 1 (CRF1) mRNA density in HMS180 rats. No rearing-associated differences in CRF2alpha binding were apparent in either the lateral septum or the ventromedial hypothalamus. These findings indicate that early rearing conditions can permanently alter the developmental set-point of central CRF systems, and potentially influence the expression of behavioral and endocrine responses to stress throughout life, thereby providing a possible neurobiological substrate for the relationship between early life events and increased vulnerability for hypothalamic-pituitary-adrenal axis and coping skill alterations and the frequency of mood disorders in patients with a history of such experiences.
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MESH Headings
- Adrenocorticotropic Hormone/cerebrospinal fluid
- Adrenocorticotropic Hormone/metabolism
- Animals
- Animals, Newborn/physiology
- Behavior, Animal/physiology
- Corticosterone/cerebrospinal fluid
- Corticosterone/metabolism
- Corticotropin-Releasing Hormone/metabolism
- Corticotropin-Releasing Hormone/physiology
- Female
- Hypothalamus/physiology
- Image Processing, Computer-Assisted
- In Situ Hybridization
- Male
- Physical Stimulation
- Pregnancy
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Radioimmunoassay
- Rats
- Rats, Long-Evans
- Receptors, Corticotropin-Releasing Hormone/biosynthesis
- Receptors, Corticotropin-Releasing Hormone/genetics
- Reflex, Startle
- Stress, Psychological/physiopathology
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Affiliation(s)
- Paul M Plotsky
- Stress Neurobiology Laboratory, Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, 1639 Pierce Drive, Atlanta, GA 30322, USA.
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Fenoglio KA, Brunson KL, Avishai-Eliner S, Stone BA, Kapadia BJ, Baram TZ. Enduring, handling-evoked enhancement of hippocampal memory function and glucocorticoid receptor expression involves activation of the corticotropin-releasing factor type 1 receptor. Endocrinology 2005; 146:4090-6. [PMID: 15932935 PMCID: PMC3100718 DOI: 10.1210/en.2004-1285] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Early-life experience, including maternal care, influences hippocampus-dependent learning and memory throughout life. Handling of pups during postnatal d 2-9 (P2-9) stimulates maternal care and leads to improved memory function and stress-coping. The underlying molecular mechanisms may involve early (by P9) and enduring reduction of hypothalamic corticotropin-releasing factor (CRF) expression and subsequent (by P45) increase in hippocampal glucocorticoid receptor (GR) expression. However, whether hypothalamic CRF levels influence changes in hippocampal GR expression (and memory function), via reduced CRF receptor activation and consequent lower plasma glucocorticoid levels, is unclear. In this study we administered selective antagonist for the type 1 CRF receptor, NBI 30775, to nonhandled rats post hoc from P10-17 and examined hippocampus-dependent learning and memory later (on P50-70), using two independent paradigms, compared with naive and vehicle-treated nonhandled, and naive and antagonist-treated handled rats. Hippocampal GR and hypothalamic CRF mRNA levels and stress-induced plasma corticosterone levels were also examined. Transient, partial selective blockade of CRF1 in nonhandled rats improved memory functions on both the Morris watermaze and object recognition tests to levels significantly better than in naive and vehicle-treated controls and were indistinguishable from those in handled (naive, vehicle-treated, and antagonist-treated) rats. GR mRNA expression was increased in hippocampal CA1 and the dentate gyrus of CRF1-antagonist treated nonhandled rats to levels commensurate with those in handled cohorts. Thus, the extent of CRF1 activation, probably involving changes in hypothalamic CRF levels and release, contributes to the changes in hippocampal GR expression and learning and memory functions.
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Affiliation(s)
- Kristina A Fenoglio
- Department of Anatomy/Neurobiology, Med Sci I, Zot: 4475, University of California, Irvine, California 92697-4475, USA
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