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Gildawie KR, Wang K, Budge KE, Byrnes EM. Effects of Maternal Separation on Effort-based Responding for Sucrose Are Associated with c-Fos Expression in the Nucleus Accumbens Core. Neuroscience 2024; 537:174-188. [PMID: 38036058 PMCID: PMC10872495 DOI: 10.1016/j.neuroscience.2023.11.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 11/06/2023] [Accepted: 11/26/2023] [Indexed: 12/02/2023]
Abstract
In both people and animals, exposure to adverse experiences early in life can alter neurodevelopment and lead to long-term behavioral effects, including effects on reward processing. In the current study, we use a well-validated rodent model of maternal neglect, maternal separation (MS), to investigate the impact of early life adversity on reward learning and motivation and identify associated modifications in cellular activation in reward-relevant areas. Litters of Long-Evans rats were separated from the dam for either 15 min (brief) or 180 min (prolonged)/day from postnatal day (PND)2 to PND14. As adults, offspring were trained to lever press for a sucrose pellet using fixed ratio (FR) schedules and motivation was tested using a progressive ratio (PR) schedule over 10 daily sessions to assess sustained effects on effort-based responding. Immunohistochemical staining for c-Fos was conducted in a subset of animals that underwent an additional PR session. While there were no effects on reward learning, both MS180 males and females demonstrated increased effort-based responding on the first day of PR testing, while only MS180 males demonstrated a sustained increase in effort across all 10 days. MS180-induced changes in c-Fos expression in the dorsal and ventral striatum were observed, with subregion-specific effects along the rostrocaudal axis. Moreover, regression analyses suggest that motivated responding for a sucrose food reward in MS180-exposed, but not MS15-exposed animals, was associated with increased c-Fos expression in the rostral nucleus accumbens core. These findings implicate specific striatal regions in sex-specific modulation of sustained effort-based reward behavior following early life adversity.
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Affiliation(s)
- Kelsea R Gildawie
- Department of Comparative Pathobiology, Cummings School of Veterinary Medicine at Tufts University, North Grafton, MA 01536, USA
| | - Katherine Wang
- Department of Comparative Pathobiology, Cummings School of Veterinary Medicine at Tufts University, North Grafton, MA 01536, USA
| | - Kerri E Budge
- Department of Comparative Pathobiology, Cummings School of Veterinary Medicine at Tufts University, North Grafton, MA 01536, USA
| | - Elizabeth M Byrnes
- Department of Comparative Pathobiology, Cummings School of Veterinary Medicine at Tufts University, North Grafton, MA 01536, USA.
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2
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Kotlinska JH, Grochecki P, Michalak A, Pankowska A, Kochalska K, Suder P, Ner-Kluza J, Matosiuk D, Marszalek-Grabska M. Neonatal Maternal Separation Induces Sexual Dimorphism in Brain Development: The Influence on Amino Acid Levels and Cognitive Disorders. Biomolecules 2023; 13:1449. [PMID: 37892131 PMCID: PMC10605115 DOI: 10.3390/biom13101449] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 09/09/2023] [Accepted: 09/23/2023] [Indexed: 10/29/2023] Open
Abstract
Repeated maternal separation (MS) is a useful experimental model in rodents for studying the long-term influence of early-life stress on brain neurophysiology. In our work, we assessed the effect of repeated MS (postnatal day (PND)1-21, 180 min/day) on the postnatal development of rat brain regions involved in memory using proton magnetic resonance spectroscopy (1HMRS) for tissue volume and the level of amino acids such as glutamate, aspartate, glutamine, glycine and gamma-aminobutyric acid (GABA) in the hippocampus. We assessed whether these effects are sex dependent. We also use novel object recognition (NOR) task to examine the effect of MS on memory and the effect of ethanol on it. Finally, we attempted to ameliorate postnatal stress-induced memory deficits by using VU-29, a positive allosteric modulator (PAM) of the metabotropic glutamate type 5 (mGlu5) receptor. In males, we noted deficits in the levels of glutamate, glycine and glutamine and increases in GABA in the hippocampus. In addition, the values of perirhinal cortex, prefrontal cortex and insular cortex and CA3 were decreased in these animals. MS females, in contrast, demonstrated significant increase in glutamate levels and decrease in GABA levels in the hippocampus. Here, the CA1 values alone were increased. VU-29 administration ameliorated these cognitive deficits. Thus, MS stress disturbs amino acids levels mainly in the hippocampus of adult male rats, and enhancement of glutamate neurotransmission reversed recognition memory deficits in these animals.
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Affiliation(s)
- Jolanta H. Kotlinska
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland;
| | - Pawel Grochecki
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland;
| | - Agnieszka Michalak
- Independent Laboratory of Behavioral Studies, Medical University, Chodzki 4A, 20-093 Lublin, Poland;
| | - Anna Pankowska
- Department of Radiography, Medical University, Staszica 16, 20-081 Lublin, Poland; (A.P.); (K.K.)
| | - Katarzyna Kochalska
- Department of Radiography, Medical University, Staszica 16, 20-081 Lublin, Poland; (A.P.); (K.K.)
| | - Piotr Suder
- Department of Analytical Chemistry and Biochemistry, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, A. Mickiewicza 30, 30-059 Krakow, Poland; (P.S.); (J.N.-K.)
| | - Joanna Ner-Kluza
- Department of Analytical Chemistry and Biochemistry, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, A. Mickiewicza 30, 30-059 Krakow, Poland; (P.S.); (J.N.-K.)
| | - Dariusz Matosiuk
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modelling Lab, Medical University, Chodzki 4A, 20-093 Lublin, Poland;
| | - Marta Marszalek-Grabska
- Department of Experimental and Clinical Pharmacology, Medical University, Jaczewskiego 8B, 20-090 Lublin, Poland;
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Solarz A, Majcher-Maślanka I, Kryst J, Chocyk A. Early-life stress affects peripheral, blood-brain barrier, and brain responses to immune challenge in juvenile and adult rats. Brain Behav Immun 2023; 108:1-15. [PMID: 36400335 DOI: 10.1016/j.bbi.2022.11.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 10/21/2022] [Accepted: 11/12/2022] [Indexed: 11/17/2022] Open
Abstract
Early-life stress (ELS) may affect brain maturation and neuroimmune interactions and, consequently, the inflammatory response to subsequent environmental factors later in life. Recently, the coexistence of blood-brain barrier (BBB) dysfunction and inflammation has been implicated in the etiology and progression of mental and/or neurodegenerative diseases. There are sex differences in the prevalence and outcomes of these disorders. The number of studies reporting the effects of ELS and sex on BBB functioning and neuroinflammatory processes in response to immune challenge is very limited, and the data are inconsistent. In the present study, we examined whether ELS, based on the maternal separation (MS) paradigm in rats, can condition male and female subjects to subsequent lipopolysaccharide (LPS)-induced immune challenge in juvenility or adulthood. Twenty-four hours after acute LPS injection, serum proinflammatory cytokines were measured, and BBB permeability in the medial prefrontal cortex (mPFC) and hippocampus (HP) was evaluated. Additionally, the mRNA expression of neuroinflammatory markers and BBB-related genes was also studied. We found that a single LPS challenge induced a proinflammatory response both in the periphery and in the mPFC and HP and increased BBB permeability in a sex-dependent fashion. Moreover, MS enhanced the neuroinflammatory response to LPS challenge in males (especially juveniles), whereas MS females showed no difference or a blunted central response to LPS compared with control females, mainly during adulthood. These results suggest that ELS may precondition individuals to subsequent environmental factors later in life in a sex-specific manner and potentially determine their susceptibility or resilience to mental and/or neurodegenerative diseases.
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Affiliation(s)
- Anna Solarz
- Department of Pharmacology, Laboratory of Pharmacology and Brain Biostructure, Maj Institute of Pharmacology, Polish Academy of Sciences, 31-343 Kraków, Smętna Street 12, Poland
| | - Iwona Majcher-Maślanka
- Department of Pharmacology, Laboratory of Pharmacology and Brain Biostructure, Maj Institute of Pharmacology, Polish Academy of Sciences, 31-343 Kraków, Smętna Street 12, Poland
| | - Joanna Kryst
- Department of Pharmacology, Laboratory of Pharmacology and Brain Biostructure, Maj Institute of Pharmacology, Polish Academy of Sciences, 31-343 Kraków, Smętna Street 12, Poland; Department of Chemistry and Biochemistry, Institute for Basics Sciences, Faculty of Physiotherapy, University of Physical Education, Jana Pawła II Av. 78, 31-571 Kraków, Poland
| | - Agnieszka Chocyk
- Department of Pharmacology, Laboratory of Pharmacology and Brain Biostructure, Maj Institute of Pharmacology, Polish Academy of Sciences, 31-343 Kraków, Smętna Street 12, Poland.
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Grochecki P, Smaga I, Surowka P, Marszalek-Grabska M, Kalaba P, Dragacevic V, Kotlinska P, Filip M, Lubec G, Kotlinska JH. Novel Dopamine Transporter Inhibitor, CE-123, Ameliorates Spatial Memory Deficits Induced by Maternal Separation in Adolescent Rats: Impact of Sex. Int J Mol Sci 2022; 23:ijms231810718. [PMID: 36142621 PMCID: PMC9503873 DOI: 10.3390/ijms231810718] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 09/06/2022] [Accepted: 09/10/2022] [Indexed: 11/16/2022] Open
Abstract
Maternal separation (MS) is a key contributor to neurodevelopmental disorders, including learning disabilities. To test the hypothesis that dopamine signaling is a major factor in this, an atypical new dopamine transporter (DAT) inhibitor, CE-123, was assessed for its potential to counteract the MS-induced spatial learning and memory deficit in male and female rats. Hence, neonatal rats (postnatal day (PND)1 to 21) were exposed to MS (180 min/day). Next, the acquisition of spatial learning and memory (Barnes maze task) and the expression of dopamine D1 receptor, dopamine transporter (DAT), and the neuronal GTPase, RIT2, which binds DAT in the vehicle-treated rats were evaluated in the prefrontal cortex and hippocampus in the adolescent animals. The results show that MS impairs the acquisition of spatial learning and memory in rats, with a more severe effect in females. Moreover, the MS induced upregulation of DAT and dopamine D1 receptors expression in the prefrontal cortex and hippocampus in adolescent rats. Regarding RIT2, the expression was decreased in the hippocampus for both the males and females, however, in the prefrontal cortex, reduction was found only in the females, suggesting that there are region-specific differences in DAT endocytic trafficking. CE-123 ameliorated the behavioral deficits associated with MS. Furthermore, it decreased the MS-induced upregulation of D1 receptor expression level in the hippocampus. These effects were more noted in females. Overall, CE-123, an atypical DAT inhibitor, is able to restore cognitive impairment and dopamine signaling in adolescent rats exposed to MS—with more evident effect in females than males.
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Affiliation(s)
- Pawel Grochecki
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland
| | - Irena Smaga
- Department of Drug Addiction Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland
| | - Paulina Surowka
- Department of Drug Addiction Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland
| | - Marta Marszalek-Grabska
- Department of Experimental and Clinical Pharmacology, Medical University, Jaczewskiego 8B, 20-090 Lublin, Poland
| | - Predrag Kalaba
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1010 Vienna, Austria
- Paracelsus Private Medical University, 5020 Salzburg, Austria
| | - Vladimir Dragacevic
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1010 Vienna, Austria
| | | | - Malgorzata Filip
- Department of Drug Addiction Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland
| | - Gert Lubec
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, 1010 Vienna, Austria
- Paracelsus Private Medical University, 5020 Salzburg, Austria
| | - Jolanta H. Kotlinska
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland
- Correspondence: ; Tel.: +48-81-448-7255; Fax: +48-81-448-7250
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Ou-Yang B, Hu Y, Fei XY, Cheng ST, Hang Y, Yang C, Cheng L. A meta-analytic study of the effects of early maternal separation on cognitive flexibility in rodent offspring. Dev Cogn Neurosci 2022; 56:101126. [PMID: 35751993 PMCID: PMC9243050 DOI: 10.1016/j.dcn.2022.101126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/27/2022] [Accepted: 06/13/2022] [Indexed: 11/03/2022] Open
Abstract
Adverse early life experiences, such as maternal separation, are associated with an increased risk for several mental health problems. Symptoms induced by maternal separation that mirror clinically relevant aspects of mental problems, such as cognitive inflexibility, open the possibility of testing putative therapeutics prior to clinical development. Although several animal (e.g., rodent) studies have evaluated the effects of early maternal separation on cognitive flexibility, no consistent conclusions have been drawn. To clarify this issue, in this study, a meta-analysis method was used to systematically explore the relationship between early maternal separation and cognitive flexibility in rodent offspring. Results indicate that early maternal separation could significantly impair cognitive flexibility in rodent offspring. Moderator analyses further showed that the relationship between early maternal separation and cognitive flexibility was not consistent in any case, but was moderated by variations in the experimental procedures, such as the deprivation levels, task characteristics, and rodent strains. These clarify the inconsistent effects of maternal separation on cognitive flexibility in rodents and help us better understand the association between early life adversity and cognitive development. Meta-analysis method was used to discuss the inconsistent effects of maternal separation on cognitive flexibility in rodent. Maternal separation was found to necessarily impair the cognitive flexibility in rodent. Variations in the experimental procedures moderated the relationship between maternal separation and cognitive flexibility. Further studies on environment-cognition associations in rodents should take experimental procedural factors into account.
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Affiliation(s)
- Bo Ou-Yang
- School of Psychology, Central China Normal University, Wuhan 430079, China
| | - Yue Hu
- School of Psychology, Central China Normal University, Wuhan 430079, China
| | - Xin-Yuan Fei
- School of Psychology, Central China Normal University, Wuhan 430079, China
| | - Sha-Te Cheng
- School of Psychology, Central China Normal University, Wuhan 430079, China
| | - Ying Hang
- School of Psychology, Central China Normal University, Wuhan 430079, China
| | - Chen Yang
- School of Psychology, Central China Normal University, Wuhan 430079, China
| | - Liang Cheng
- School of Psychology, Central China Normal University, Wuhan 430079, China.
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Filarowska-Jurko J, Komsta L, Smaga I, Surowka P, Marszalek-Grabska M, Grochecki P, Nizio D, Filip M, Kotlinska JH. Maternal Separation Alters Ethanol Drinking and Reversal Learning Processes in Adolescent Rats: The Impact of Sex and Glycine Transporter Type 1 (GlyT1) Inhibitor. Int J Mol Sci 2022; 23:ijms23105350. [PMID: 35628160 PMCID: PMC9141364 DOI: 10.3390/ijms23105350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 05/07/2022] [Accepted: 05/09/2022] [Indexed: 11/16/2022] Open
Abstract
Adverse early life experiences are associated with an enhanced risk for mental and physical health problems, including substance abuse. Despite clinical evidence, the mechanisms underlying these relationships are not fully understood. Maternal separation (MS) is a commonly used animal model of early neglect. The aim of the current study is to determine whether the N-methyl-D-aspartate receptor (NMDAR)/glycine sites are involved in vulnerability to alcohol consumption (two-bottle choice paradigm) and reversal learning deficits (Barnes maze task) in adolescent rats subjected to the MS procedure and whether these effects are sex dependent. By using ELISA, we evaluated MS-induced changes in the NMDAR subunits (GluN1, GluN2A, GluN2B) expression, especially in the glycine-binding subunit, GluN1, in the prefrontal cortex (PFC) and ventral striatum (vSTR) of male/female rats. Next, we investigated whether Org 24598, a glycine transporter 1 (GlyT1) inhibitor, was able to modify ethanol drinking in adolescent and adult male/female rats with prior MS experience and reversal learning in the Barnes maze task. Our findings revealed that adolescent MS female rats consumed more alcohol which may be associated with a substantial increase in GluN1 subunit of NMDAR in the PFC and vSTR. Org 24598 decreased ethanol intake in both sexes with a more pronounced decrease in ethanol consumption in adolescent female rats. Furthermore, MS showed deficits in reversal learning in both sexes. Org 24598 ameliorated reversal learning deficits, and this effect was reversed by the NMDAR/glycine site inhibitor, L-701,324. Collectively, our results suggest that NMDAR/glycine sites might be targeted in the treatment of alcohol abuse in adolescents with early MS, especially females.
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Affiliation(s)
- Joanna Filarowska-Jurko
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland; (J.F.-J.); (P.G.)
| | - Lukasz Komsta
- Department of Medicinal Chemistry, Medical University, Jaczewskiego 4, 20-090 Lublin, Poland;
| | - Irena Smaga
- Department of Drug Addiction Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-324 Krakow, Poland; (I.S.); (P.S.); (M.F.)
| | - Paulina Surowka
- Department of Drug Addiction Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-324 Krakow, Poland; (I.S.); (P.S.); (M.F.)
| | - Marta Marszalek-Grabska
- Department of Experimental and Clinical Pharmacology, Medical University, Jaczewskiego 8b, 20-090 Lublin, Poland;
| | - Pawel Grochecki
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland; (J.F.-J.); (P.G.)
| | - Dorota Nizio
- Experimental Medicine Center, Medical University, Jaczewskiego 8, 20-090 Lublin, Poland;
| | - Malgorzata Filip
- Department of Drug Addiction Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-324 Krakow, Poland; (I.S.); (P.S.); (M.F.)
| | - Jolanta H. Kotlinska
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland; (J.F.-J.); (P.G.)
- Correspondence: ; Tel.: +48-81-448-7255; Fax: +48-81-448-7250
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John Jayakumar JAK, Panicker MM. The roles of serotonin in cell adhesion and migration, and cytoskeletal remodeling. Cell Adh Migr 2021; 15:261-271. [PMID: 34494935 PMCID: PMC8437456 DOI: 10.1080/19336918.2021.1963574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 07/04/2021] [Accepted: 07/29/2021] [Indexed: 11/22/2022] Open
Abstract
Serotonin is well known as a neurotransmitter. Its roles in neuronal processes such as learning, memory or cognition are well established, and also in disorders such as depression, schizophrenia, bipolar disorder, and dementia. However, its effects on adhesion and cytoskeletal remodelling which are strongly affected by 5-HT receptors, are not as well studied with some exceptions for e.g. platelet aggregation. Neuronal function is strongly dependent on cell-cell contacts and adhesion-related processes. Therefore the role played by serotonin in psychiatric illness, as well as in the positive and negative effects of neuropsychiatric drugs through cell-related adhesion can be of great significance. In this review, we explore the role of serotonin in some of these aspects based on recent findings.
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Affiliation(s)
- Joe Anand Kumar John Jayakumar
- Manipal Academy of Higher Education, Manipal, India
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
| | - Mitradas M. Panicker
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
- Present Address - Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, USA
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Solarz A, Majcher-Maślanka I, Chocyk A. Effects of early-life stress and sex on blood-brain barrier permeability and integrity in juvenile and adult rats. Dev Neurobiol 2021; 81:861-876. [PMID: 34320279 DOI: 10.1002/dneu.22846] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/14/2021] [Accepted: 07/16/2021] [Indexed: 12/22/2022]
Abstract
Early-life stress (ELS) is considered a relevant etiological factor for neurodegenerative and mental disorders. In the present study, we hypothesized that ELS may persistently and sex dependently influence blood-brain barrier (BBB) integrity and function during critical periods of brain development and consequently determine susceptibility to and sex-related prevalence of chronic diseases in adult life. We used the maternal separation (MS) procedure in rats to model ELS and evaluated BBB permeability and gene expression of selected tight junction (TJ) proteins, glucose transporter type 1 (Slc2a1) and aquaporin 4 (Aqp4) in the medial prefrontal cortex (mPFC), dorsal striatum (dSTR) and hippocampus of juvenile and adult rats. Serum concentrations of a peripheral marker of BBB function (S100β) and proinflammatory cytokines were also assessed. We observed developmental sealing of the BBB and sex differences in the permeability of the BBB and the mRNA expression of TJ proteins and Slc2a1. Adult females showed lower BBB permeability and higher levels of Cldn3, Cldn5, Ocln, and Slc2a1 in the mPFC and dSTR than males. MS temporarily increased BBB permeability in the dSTR of juvenile males and affected mRNA expression of the majority of studied proteins related to BBB function in age-, region- and sex-dependent manners. Additionally, MS sex dependently decreased serum S100β levels and did not affect proinflammatory cytokine concentrations. In general, our study did not reveal a clear or strong negative effect of MS on BBB integrity. However, the results suggest that ELS may induce adaptive/maladaptive changes or compensatory mechanisms within the BBB of unknown yet consequences.
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Affiliation(s)
- Anna Solarz
- Department of Pharmacology, Laboratory of Pharmacology and Brain Biostructure, Maj Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
| | - Iwona Majcher-Maślanka
- Department of Pharmacology, Laboratory of Pharmacology and Brain Biostructure, Maj Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
| | - Agnieszka Chocyk
- Department of Pharmacology, Laboratory of Pharmacology and Brain Biostructure, Maj Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
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9
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Zou C, Huang X, Lan X, Huang X, Feng Y, Huang J, Meng L, Jian C, Zou D, Wang J, Li X. Potential Genes and Mechanisms Linking Intracerebral Hemorrhage and Depression: A Bioinformatics-Based Study. Int J Gen Med 2021; 14:1213-1226. [PMID: 33854363 PMCID: PMC8039224 DOI: 10.2147/ijgm.s302916] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 03/17/2021] [Indexed: 12/16/2022] Open
Abstract
Purpose The purpose of this study was to investigate the potential pathogenic mechanisms of post-intracerebral hemorrhage depression. Methods Profiles of gene expression in brain tissue of patients with intracerebral hemorrhage (ICH) or depression were downloaded from the Gene Expression Omnibus (GEO) database. We analyzed differentially expressed genes (DEGs) for the two diseases separately. With these DEGs, we conducted an enrichment analysis based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) as well as cross-talk analysis, then we identified hub bridge genes using integrated bridge landscape analysis. Results We found 131 DEGs for interaction between ICH and depression. In the enrichment analysis, we found 55 GO terms and KEGG pathways involving interacting genes of ICH and depression, and 10 GO terms and 10 KEGG pathways most significantly related to cross-talk between ICH and depression. In the integrated bridge landscape analysis, we identified 20 hub bridge genes. In further analysis, we found that hub bridge genes HLA-A, HMOX1, and JUN related to endocytosis, cell adhesion, and phagosomes may exert their effects through the dopamine (DA) system and the serotonergic pathway post-ICH depression. HLA-A may play a role in the occurrence and development of ICH and depression through immune mediation and cell adhesion. HMOX1 and JUN may participate in the mechanism by interacting with HLA-A. Conclusion Through bioinformatics analysis, we identified potential hub bridge genes and pathways related to post-ICH depression. Our study provides references for further research on mechanisms on the pathogenesis of post-ICH depression.
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Affiliation(s)
- Cuihua Zou
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China.,Department of Neurology, Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China
| | - Xiaohua Huang
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China.,Department of Neurology, Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China
| | - Xuequn Lan
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China
| | - Xiaorui Huang
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China
| | - Yun Feng
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China
| | - Jianmin Huang
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China
| | - Lanqing Meng
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China
| | - Chongdong Jian
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China
| | - Donghua Zou
- Department of Neurology, The Fifth Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, 530022, People's Republic of China
| | - Jie Wang
- Department of Nephrology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China
| | - Xuebin Li
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China.,Department of Neurology, Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, People's Republic of China
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10
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Life-course effects of early life adversity exposure on eating behavior and metabolism. ADVANCES IN FOOD AND NUTRITION RESEARCH 2021; 97:237-273. [PMID: 34311901 DOI: 10.1016/bs.afnr.2021.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Environmental variations in early life influence brain development, making individuals more vulnerable to psychiatric and metabolic disorders. Early life stress (ELS) has a strong impact on the development of eating behavior. However, eating is a complex behavior, determined by an interaction between signals of energy homeostasis, neuronal circuits involved in its regulation, and circuits related to rewarding properties of the food. Although mechanisms underlying ELS-induced altered feeding behavior are not completely understood, evidence suggest that the effects of ELS on metabolic, mood, and emotional disorders, as well as reward system dysfunctions can contribute directly or indirectly to altered feeding behavior. The focus of this chapter is to discuss the effects of ELS on eating behavior and metabolism, considering different factors that control appetite such as energy homeostasis, hedonic properties of the food, emotional and cognitive status. After highlighting classic studies on the association between ELS and eating behavior alterations, we discuss how exposure to adversity can interact with genetics characteristics to predict variable outcomes.
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Gildawie KR, Ryll LM, Hexter JC, Peterzell S, Valentine AA, Brenhouse HC. A two-hit adversity model in developing rats reveals sex-specific impacts on prefrontal cortex structure and behavior. Dev Cogn Neurosci 2021; 48:100924. [PMID: 33515957 PMCID: PMC7847967 DOI: 10.1016/j.dcn.2021.100924] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 02/07/2023] Open
Abstract
Adversity early in life substantially impacts prefrontal cortex (PFC) development and vulnerability to later-life psychopathology. Importantly, repeated adverse experiences throughout childhood increase the risk for PFC-mediated behavioral deficits more commonly in women. Evidence from animal models points to effects of adversity on later-life neural and behavioral dysfunction; however, few studies have investigated the neurobiological underpinnings of sex-specific, long-term consequences of multiple developmental stressors. We modeled early life adversity in rats via maternal separation (postnatal day (P)2-20) and juvenile social isolation (P21-35). In adulthood, anxiety-like behavior was assessed in the elevated zero maze and the presence and structural integrity of PFC perineuronal nets (PNNs) enwrapping parvalbumin (PV)-expressing interneurons was quantified. PNNs are extracellular matrix structures formed during critical periods in postnatal development that play a key role in the plasticity of PV cells. We observed a female-specific effect of adversity on hyperactivity and risk-assessment behavior. Moreover, females – but not males – exposed to multiple hits of adversity demonstrated a reduction in PFC PV cells in adulthood. We also observed a sex-specific, potentiated reduction in PV + PNN structural integrity. These findings suggest a sex-specific impact of repeated adversity on neurostructural development and implicate PNNs as a contributor to associated behavioral dysfunction.
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Affiliation(s)
| | - Lilly M Ryll
- Department of Psychology, Northeastern University, Boston, MA, USA
| | - Jessica C Hexter
- Department of Psychology, Northeastern University, Boston, MA, USA
| | - Shayna Peterzell
- Department of Psychology, Northeastern University, Boston, MA, USA
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12
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Lopatina OL, Panina YA, Malinovskaya NA, Salmina AB. Early life stress and brain plasticity: from molecular alterations to aberrant memory and behavior. Rev Neurosci 2020; 32:131-142. [PMID: 33550784 DOI: 10.1515/revneuro-2020-0077] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 10/11/2020] [Indexed: 12/13/2022]
Abstract
Early life stress (ELS) is one of the most critical factors that could modify brain plasticity, memory and learning abilities, behavioral reactions, and emotional response in adulthood leading to development of different mental disorders. Prenatal and early postnatal periods appear to be the most sensitive periods of brain development in mammals, thereby action of various factors at these stages of brain development might result in neurodegeneration, memory impairment, and mood disorders at later periods of life. Deciphering the processes underlying aberrant neurogenesis, synaptogenesis, and cerebral angiogenesis as well as deeper understanding the effects of ELS on brain development will provide novel approaches to prevent or to cure psychiatric and neurological deficits caused by stressful conditions at the earliest stages of ontogenesis. Neuropeptide oxytocin serves as an amnesic, anti-stress, pro-angiogenic, and neurogenesis-controlling molecule contributing to dramatic changes in brain plasticity in ELS. In the current review, we summarize recent data on molecular mechanisms of ELS-driven changes in brain plasticity with the particular focus on oxytocin-mediated effects on neurogenesis and angiogenesis, memory establishment, and forgetting.
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Affiliation(s)
- Olga L Lopatina
- Research Institute of Molecular Medicine and Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, Krasnoyarsk, Russia.,Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, Krasnoyarsk, Russia.,Department of Biophysics, Siberian Federal University, Krasnoyarsk, Russia
| | - Yulia A Panina
- Research Institute of Molecular Medicine and Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, Krasnoyarsk, Russia.,Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, Krasnoyarsk, Russia
| | - Natalia A Malinovskaya
- Research Institute of Molecular Medicine and Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, Krasnoyarsk, Russia.,Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, Krasnoyarsk, Russia
| | - Alla B Salmina
- Research Institute of Molecular Medicine and Pathobiochemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, Krasnoyarsk, Russia.,Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, Krasnoyarsk, Russia
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13
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Impact of Maternal Separation on Dopamine System and its Association with Parkinson's Disease. Neuromolecular Med 2020; 22:335-340. [PMID: 31933131 DOI: 10.1007/s12017-019-08587-x] [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: 08/22/2019] [Accepted: 12/25/2019] [Indexed: 01/09/2023]
Abstract
As a type of stress, maternal separation (MS) has been one of the most widely used models in neuropsychiatric research. An increasing number of studies has found that MS not only affects the function of the hypothalamic-pituitary-adrenal axis and hippocampal 5-hydroxytryptamine system, but also causes dysfunction of the central dopamine (DA) system and increases the susceptibility of dopaminergic neurons to pathogenic factors of Parkinson's disease (PD), for instance, 6-hydroxydopamine, thus impairing motor function. We reviewed the impact of MS on the DA system and its correlation with PD and found the following: (1) discrepant effects of MS on the DA system have been reported; (2) MS is a good model to study the impact of stress on the occurrence and development of PD, however, unified modeling criteria of MS are required; (3) correlation between MS and PD may involve the impact of MS on the DA system, which however is not the only connection; (4) intervening measures can block pathways between MS and PD, which provides reference for the prevention of PD in specific populations such as left-behind children.
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14
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Goodwill HL, Manzano-Nieves G, Gallo M, Lee HI, Oyerinde E, Serre T, Bath KG. Early life stress leads to sex differences in development of depressive-like outcomes in a mouse model. Neuropsychopharmacology 2019; 44:711-720. [PMID: 30188513 PMCID: PMC6372611 DOI: 10.1038/s41386-018-0195-5] [Citation(s) in RCA: 149] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 07/29/2018] [Accepted: 07/31/2018] [Indexed: 01/01/2023]
Abstract
Childhood trauma and neglect influence emotional development and increase the risk for and severity of mental illness. Women have a heightened susceptibility to the effects of early life stress (ELS) and are twice as likely as men to develop debilitating, stress-associated disorders later in life, such as major depressive disorder (MDD). Until now, mouse models of depression have been largely unsuccessful at replicating the diverse symptomatology of this disease and the sex bias in vulnerability. From P4 to P11, a limited bedding model that leads to fragmented maternal care, was used to induce ELS. Early adolescent and young adult mice were tested on an array of assays to test for depressive-like behavior. This included our newly developed automated home cage behavioral recognition system, where the home cage behavior of ELS and control mice could be monitored over a continuous 5-10 day span. ELS females, but not males, exhibited depressive-like behaviors on traditional assays. These effects emerged during adolescence and became more severe in adulthood. Using the novel home cage video monitoring method, we identified robust and continuous markers of depressive-like pathology in ELS females that phenocopy many of the behavioral characteristics of depression in humans. ELS effects on home cage behavior were rapidly rescued by ketamine, a fast-acting antidepressant. Together, these findings highlight that limited bedding ELS (1) produces an early emerging, female-specific depressive phenotype that responds to a fast-acting antidepressant and (2) this model has the potential to inform sex-selective risk for the development of stress-induced mental illness.
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Affiliation(s)
- Haley L. Goodwill
- 0000 0004 1936 9094grid.40263.33Department of Neuroscience, Brown University, Providence, RI 02912 USA
| | - Gabriela Manzano-Nieves
- 0000 0004 1936 9094grid.40263.33Department of Neuroscience, Brown University, Providence, RI 02912 USA
| | - Meghan Gallo
- 0000 0004 1936 9094grid.40263.33Department of Cognitive, Linguistic, and Psychological Sciences, Brown University, Providence, RI 02912 USA
| | - Hye-In Lee
- 0000 0004 1936 9094grid.40263.33Department of Neuroscience, Brown University, Providence, RI 02912 USA
| | - Esther Oyerinde
- 0000 0004 1936 9094grid.40263.33Department of Neuroscience, Brown University, Providence, RI 02912 USA
| | - Thomas Serre
- 0000 0004 1936 9094grid.40263.33Department of Cognitive, Linguistic, and Psychological Sciences, Brown University, Providence, RI 02912 USA
| | - Kevin G. Bath
- 0000 0004 1936 9094grid.40263.33Department of Cognitive, Linguistic, and Psychological Sciences, Brown University, Providence, RI 02912 USA
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Majcher-Maślanka I, Solarz A, Wędzony K, Chocyk A. Previous Early-life Stress Modifies Acute Corticosterone-induced Synaptic Plasticity in the Medial Prefrontal Cortex of Adolescent Rats. Neuroscience 2018; 379:316-333. [DOI: 10.1016/j.neuroscience.2018.03.038] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 03/15/2018] [Accepted: 03/21/2018] [Indexed: 01/21/2023]
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16
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Ganguly P, Thompson V, Gildawie K, Brenhouse HC. Adolescent food restriction in rats alters prefrontal cortex microglia in an experience-dependent manner. Stress 2018; 21:162-168. [PMID: 29307257 PMCID: PMC6109256 DOI: 10.1080/10253890.2017.1423054] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Microglia are resident immune cells of the brain that can regulate neural communication and excitability. Any environmental influence on microglial activity has the potential to alter subsequent neural physiology and behavior. Within the prefrontal cortex, several types of stressors have been shown to increase microglial expression of activation markers such as ionized calcium-binding adapter molecule-1 (Iba-1), which suggests altered microglial activity. Recent reports in rodents suggest that exposure to forms of early-life stress such as maternal separation can alter microglial responsivity to subsequent challenges. Several learning paradigms used in rodents require food restriction to provoke motivational states that facilitate approach behaviors. Here, we tested whether food restriction (increasing from 13 g/day-23 g/day in males and 10 g/day-20 g/day in females, which reduced body weight to 72-84% free-fed weight) in adolescent rats is a sufficient challenge to affect microglial Iba-1 expression, and whether previous exposure to postnatal maternal separation influenced microglial outcomes. We measured prefrontal cortex Iba-1 expression and microglial morphology after 20 days of ad libitum or restricted food availability in males and females with or without exposure to maternal separation. Food-restricted animals displayed higher levels of Iba-1 in the prefrontal cortex, with hyper-ramified microglial morphology in maternally separated males and control females, compared to those that were free-fed. Together, our data provide evidence that food restriction paradigms may have unintended effects in some behavioral protocols.
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Barzilay R, Ventorp F, Segal-Gavish H, Aharony I, Bieber A, Dar S, Vescan M, Globus R, Weizman A, Naor D, Lipton J, Janelidze S, Brundin L, Offen D. CD44 Deficiency Is Associated with Increased Susceptibility to Stress-Induced Anxiety-like Behavior in Mice. J Mol Neurosci 2016; 60:548-558. [DOI: 10.1007/s12031-016-0835-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 08/30/2016] [Indexed: 12/21/2022]
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18
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Calabrese F, Riva MA, Molteni R. Synaptic alterations associated with depression and schizophrenia: potential as a therapeutic target. Expert Opin Ther Targets 2016; 20:1195-207. [PMID: 27167520 DOI: 10.1080/14728222.2016.1188080] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION In recent years, the concept of 'synaptopathy' has been extended from neurodegenerative and neurological disorders to psychiatric diseases. According to this nascent line of research, disruption in synaptic structure and function acts as the main determinant of mental illness. Therefore, molecular systems and processes crucial for synaptic activity may represent promising therapeutic targets. AREAS COVERED We review data on synaptic structural alterations in depression and schizophrenia and on specific molecular systems and/or mechanisms important for the maintenance of proper synaptic function. Specifically, we examine the involvement of the neuroligin system, the local protein translation, and the neurotrophin BDNF by reviewing clinical and preclinical studies, with particular attention to results provided by using animal models based on the role of stress in psychiatric diseases. Finally, we also discuss the impact of pharmacological treatment on these molecular systems/mechanisms. EXPERT OPINION The relevance of synaptic dysfunctions in psychiatric diseases is undoubted and the potential to normalize, ameliorate, and shape such alterations by acting on molecular systems crucial to ensure synaptic function property is fascinating. However, future studies are required to elucidate several open issues.
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Affiliation(s)
- Francesca Calabrese
- a Dipartimento di Scienze Farmacologiche e Biomolecolari , Università degli Studi di Milano , Milan , Italy
| | - Marco A Riva
- a Dipartimento di Scienze Farmacologiche e Biomolecolari , Università degli Studi di Milano , Milan , Italy
| | - Raffaella Molteni
- a Dipartimento di Scienze Farmacologiche e Biomolecolari , Università degli Studi di Milano , Milan , Italy
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19
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Ventorp F, Barzilay R, Erhardt S, Samuelsson M, Träskman-Bendz L, Janelidze S, Weizman A, Offen D, Brundin L. The CD44 ligand hyaluronic acid is elevated in the cerebrospinal fluid of suicide attempters and is associated with increased blood-brain barrier permeability. J Affect Disord 2016; 193:349-54. [PMID: 26796235 DOI: 10.1016/j.jad.2015.12.069] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 12/07/2015] [Accepted: 12/26/2015] [Indexed: 12/17/2022]
Abstract
BACKGROUND The glycosaminoglycan hyaluronic acid (HA) is an important component of the extracellular matrix (ECM) in the brain. CD44 is a cell adhesion molecule that binds to HA in the ECM and is present on astrocytes, microglia and certain neurons. Cell adhesion molecules have been reported to be involved in anxiety and mood disorders. CD44 levels are decreased in the cerebrospinal fluid (CSF) of depressed individuals, and the CD44 gene has been identified in brain GWAS studies as a possible risk gene for suicidal behavior. METHOD We measured the CSF levels of HA and the soluble CD44 (sCD44) in suicide attempters (n=94) and in healthy controls (n=45) using ELISA and electrochemiluminescence assays. We also investigated other proteins known to interact with CD44, such as osteopontin and the matrix metalloproteinases MMP1, MMP3 and MMP9. RESULTS The suicide attempters had higher CSF levels of HA (p=.003) and MMP9 (p=.004). The CSF levels of HA correlated with BBB-permeability (rho=0.410, p<.001) and MMP9 correlated with sCD44 levels (rho=0.260, p=.005). LIMITATIONS Other relevant biological contributors to suicidal behavior is not addressed in parallel to the specific role of CD44-HA signaling. The gender distribution of the patients from whom CSF was analyzed was uneven. CONCLUSIONS Increased BBB-permeability and HA levels might be a results of increased neuroinflammation and can play a role in the pathobiology of suicidal behavior. The CD44 signaling pathway might be considered a novel target for intervention in mood disorders.
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Affiliation(s)
- F Ventorp
- Psychoimmunology Unit, Division of Psychiatry, Department of Clinical Sciences, Lund University, Lund, Sweden; Department of Psychiatry and Behavioral Medicine, Michigan State University, Grand Rapids, Michigan, United States.
| | - R Barzilay
- Laboratory of Neuroscience, Felsenstein Medical Research Center, Sackler Faculty of Medicine, Tel Aviv University, Petach-Tikva, Israel; Research Unit at Geha Mental Health Center, Petach-Tikva, Israel
| | - S Erhardt
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - M Samuelsson
- Psychiatry Section, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
| | - L Träskman-Bendz
- Psychoimmunology Unit, Division of Psychiatry, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - S Janelidze
- Psychoimmunology Unit, Division of Psychiatry, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - A Weizman
- Research Unit at Geha Mental Health Center, Petach-Tikva, Israel; Laboratory of Biological Psychiatry, Felsenstein Medical Research Center, Rabin Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Israel
| | - D Offen
- Laboratory of Neuroscience, Felsenstein Medical Research Center, Sackler Faculty of Medicine, Tel Aviv University, Petach-Tikva, Israel
| | - L Brundin
- Psychoimmunology Unit, Division of Psychiatry, Department of Clinical Sciences, Lund University, Lund, Sweden; Department of Psychiatry and Behavioral Medicine, Michigan State University, Grand Rapids, Michigan, United States; Laboratory of Behavioral Medicine, Van Andel Research Institute, Grand Rapids, Michigan, United States
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20
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do Prado CH, Narahari T, Holland FH, Lee HN, Murthy SK, Brenhouse HC. Effects of early adolescent environmental enrichment on cognitive dysfunction, prefrontal cortex development, and inflammatory cytokines after early life stress. Dev Psychobiol 2015; 58:482-91. [PMID: 26688108 DOI: 10.1002/dev.21390] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 12/02/2015] [Indexed: 01/11/2023]
Abstract
Early postnatal stress such as maternal separation causes cognitive dysfunction later in life, including working memory deficits that are largely mediated by the prefrontal cortex. Maternal separation in male rats also yields a loss of parvalbumin-containing prefrontal cortex interneurons in adolescence, which may occur via inflammatory or oxidative stress mechanisms. Environmental enrichment can prevent several effects of maternal separation; however, effects of enrichment on prefrontal cortex development are not well understood. Here, we report that enrichment prevented cognitive dysfunction in maternally separated males and females, and prevented elevated circulating pro-inflammatory cytokines that was evident in maternally separated males, but not females. However, enrichment did not prevent parvalbumin loss or adolescent measures of oxidative stress. Significant correlations indicated that adolescents with higher oxidative damage and less prefrontal cortex parvalbumin in adolescence committed more errors on the win-shift task; therefore, maternal separation may affect cognitive dysfunction via aberrant interneuron development. © 2015 Wiley Periodicals, Inc. Dev Psychobiol 58: 482-491, 2016.
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Affiliation(s)
- Carine H do Prado
- Department of Psychology, Northeastern University, Boston, MA.,Developmental Cognitive Neuroscience Research Group (GNCD), Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Tanya Narahari
- Department of Chemical Engineering, Northeastern University, Boston, MA
| | | | - Ha-Neul Lee
- Department of Psychology, Northeastern University, Boston, MA
| | - Shashi K Murthy
- Department of Chemical Engineering, Northeastern University, Boston, MA.,Barnett Institute of Chemical and Biological Analysis, Northeastern University, Boston, MA
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21
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Thomas AW, Caporale N, Wu C, Wilbrecht L. Early maternal separation impacts cognitive flexibility at the age of first independence in mice. Dev Cogn Neurosci 2015; 18:49-56. [PMID: 26531108 PMCID: PMC4834230 DOI: 10.1016/j.dcn.2015.09.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 09/10/2015] [Accepted: 09/21/2015] [Indexed: 01/10/2023] Open
Abstract
MS mice tested in 4-choice task as juveniles are less flexible than littermates. MS mice tested in adulthood in 4-choice paradigm do not differ from littermates. MS mice showed greater ethanol consumption compared to littermates in adulthood.
Early life adversity is associated with increased risk for mental and physical health problems, including substance abuse. Changes in neural development caused by early life insults could cause or complicate these conditions. Maternal separation (MS) is a model of early adversity for rodents. Clear effects of MS have been shown on behavioral flexibility in rats, but studies of effects of MS on cognition in mice have been mixed. We hypothesized that previous studies focused on adult mice may have overlooked a developmental transition point when juvenile mice exhibit greater flexibility in reversal learning. Here, using a 4-choice reversal learning task we find that early MS leads to decreased flexibility in post-weaning juvenile mice, but no significant effects in adults. In a further study of voluntary ethanol consumption, we found that adult mice that had experienced MS showed greater cumulative 20% ethanol consumption in an intermittent access paradigm compared to controls. Our data confirm that the MS paradigm can reduce cognitive flexibility in mice and may enhance risk for substance abuse. We discuss possible interpretations of these data as stress-related impairment or adaptive earlier maturation in response to an adverse environment.
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Affiliation(s)
| | - Natalia Caporale
- University of California Berkeley, Psychology Department; Helen Wills Neuroscience Institute
| | - Claudia Wu
- University of California Irvine, Neurobiology and Behavior Graduate Program
| | - Linda Wilbrecht
- University of California Berkeley, Psychology Department; Helen Wills Neuroscience Institute.
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22
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Early‐life stress increases the survival of midbrain neurons during postnatal development and enhances reward‐related and anxiolytic‐like behaviors in a sex‐dependent fashion. Int J Dev Neurosci 2015; 44:33-47. [DOI: 10.1016/j.ijdevneu.2015.05.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 05/07/2015] [Accepted: 05/08/2015] [Indexed: 01/30/2023] Open
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Wędzony K, Chocyk A, Maćkowiak M. Potential roles of NCAM/PSA-NCAM proteins in depression and the mechanism of action of antidepressant drugs. Pharmacol Rep 2014; 65:1471-8. [PMID: 24552994 DOI: 10.1016/s1734-1140(13)71507-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 09/20/2013] [Indexed: 01/05/2023]
Abstract
Recently, it has been proposed that abnormalities in neuronal structural plasticity may underlie the pathogenesis of major depression, resulting in changes in the volume of specific brain regions, including the hippocampus (HIP), the prefrontal cortex (PC), and the amygdala (AMY), as well as the morphology of individual neurons in these brain regions. In the present survey, we compile the data regarding the involvement of the neural cell adhesion molecule (NCAM) protein and its polysialylated form (PSA-NCAM) in the pathogenesis of depression and the mechanism of action of antidepressant drugs (ADDs). Elevated expression of PSA-NCAM may reflect neuroplastic changes, whereas decreased expression implies a rigidification of neuronal morphology and an impedance of dynamic changes in synaptic structure. Special emphasis is placed on the clinical data, genetic models, and the effects of ADDs on NCAM/PSA-NCAM expression in the brain regions in which these proteins are constitutively expressed and neurogenesis is not a major factor; this emphasis is necessary to prevent cell proliferation and neurogenesis from obscuring the issue of brain plasticity.
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Affiliation(s)
- Krzysztof Wędzony
- Laboratory of Pharmacology and Brain Biostructure, Department of Pharmacologcy, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, PL 31-343 Kraków, Poland.
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Chocyk A, Majcher-Maślanka I, Dudys D, Przyborowska A, Wędzony K. Impact of early-life stress on the medial prefrontal cortex functions - a search for the pathomechanisms of anxiety and mood disorders. Pharmacol Rep 2014; 65:1462-70. [PMID: 24552993 DOI: 10.1016/s1734-1140(13)71506-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 10/03/2013] [Indexed: 01/21/2023]
Abstract
Although anxiety and mood disorders (MDs) are the most common mental diseases, the etiologies and mechanisms of these psychopathologies are still a matter of debate. The medial prefrontal cortex (mPFC) is a brain structure that is strongly implicated in the pathophysiology of these disorders. A growing number of epidemiological and clinical studies show that early-life stress (ELS) during the critical period of brain development may increase the risk for anxiety and MDs. Neuroimaging analyses in humans and numerous reports from animal models clearly demonstrate that ELS affects behaviors that are dependent on the mPFC, as well as neuronal activity and synaptic plasticity within the mPFC. The mechanisms engaged in ELS-induced changes in mPFC function involve alterations in the developmental trajectory of the mPFC and may be responsible for the emergence of both early-onset (during childhood and adolescence) and adulthood-onset anxiety and MDs. ELS-evoked changes in mPFC synaptic plasticity may constitute an example of metaplasticity. ELS may program brain functions by affecting glucocorticoid levels. On the molecular level, ELS-induced programming is registered by epigenetic mechanisms, such as changes in DNA methylation pattern, histone acetylation and microRNA expression. Vulnerability and resilience to ELS-related anxiety and MDs depend on the interaction between individual genetic predispositions, early-life experiences and later-life environment. In conclusion, ELS may constitute a significant etiological factor for anxiety and MDs, whereas animal models of ELS are helpful tools for understanding the pathomechanisms of these disorders.
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Affiliation(s)
- Agnieszka Chocyk
- Laboratory of Pharmacology and Brain Biostructure, Department of Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, PL 31-343 Kraków, Poland.
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Long-term effects of maternal deprivation on the neuronal soma area in the rat neocortex. BIOMED RESEARCH INTERNATIONAL 2014; 2014:235238. [PMID: 24895554 PMCID: PMC4034405 DOI: 10.1155/2014/235238] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 04/10/2014] [Accepted: 04/12/2014] [Indexed: 01/01/2023]
Abstract
Early separation of rat pups from their mothers (separatio a matrem) is considered and accepted as an animal model of perinatal stress. Adult rats, separated early postnatally from their mothers, are developing long-lasting changes in the brain and neuroendocrine system, corresponding to the findings observed in schizophrenia and affective disorders. With the aim to investigate the morphological changes in this animal model we exposed 9-day-old (P9) Wistar rats to a 24 h maternal deprivation (MD). At young adult age rats were sacrificed for morphometric analysis and their brains were compared with the control group bred under the same conditions, but without MD. Rats exposed to MD had a 28% smaller cell soma area in the prefrontal cortex (PFCX), 30% in retrosplenial cortex (RSCX), and 15% in motor cortex (MCX) compared to the controls. No difference was observed in the expression of glial fibrillary acidic protein in the neocortex of MD rats compared to the control group. The results of this study demonstrate that stress in early life has a long-term effect on neuronal soma size in cingulate and retrosplenial cortex and is potentially interesting as these structures play an important role in cognition.
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26
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The effects of early-life adversity on fear memories in adolescent rats and their persistence into adulthood. Behav Brain Res 2014; 264:161-72. [DOI: 10.1016/j.bbr.2014.01.040] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Revised: 01/27/2014] [Accepted: 01/28/2014] [Indexed: 01/18/2023]
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Chocyk A, Bobula B, Dudys D, Przyborowska A, Majcher-Maślanka I, Hess G, Wędzony K. Early-life stress affects the structural and functional plasticity of the medial prefrontal cortex in adolescent rats. Eur J Neurosci 2013; 38:2089-107. [PMID: 23581639 DOI: 10.1111/ejn.12208] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 03/03/2013] [Indexed: 02/06/2023]
Abstract
Early life experiences are crucial factors that shape brain development and function due to their ability to induce structural and functional plasticity. Among these experiences, early-life stress (ELS) is known to interfere with brain development and maturation, increasing the risk of future psychopathologies, including depression, anxiety, and personality disorders. Moreover, ELS may contribute to the emergence of these psychopathologies during adolescence. In this present study, we investigated the effects of ELS, in the form of maternal separation (MS), on the structural and functional plasticity of the medial prefrontal cortex (mPFC) and anxiety-like behavior in adolescent male rats. We found that the MS procedure resulted in disturbances in mother-pup interactions that lasted until weaning and were most strongly demonstrated by increases in nursing behavior. Moreover, MS caused atrophy of the basal dendritic tree and reduced spine density on both the apical and basal dendrites in layer II/III pyramidal neurons of the mPFC. The structural changes were accompanied by an impairment of long-term potentiation processes and increased expression of key proteins, specifically glutamate receptor 1, glutamate receptor 2, postsynaptic density protein 95, αCa(2+) /calmodulin-dependent protein kinase II and αCa(2+)/calmodulin-dependent protein kinase II phosphorylated at residue Thr305, that are engaged in long-term potentiation induction and maintenance in the mPFC. We also found that the MS animals were more anxious in the light/dark exploration test. The results of this study indicate that ELS has a significant impact on the structural and functional plasticity of the mPFC in adolescents. ELS-induced adaptive plasticity may underlie the pathomechanisms of some early-onset psychopathologies observed in adolescents.
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Affiliation(s)
- Agnieszka Chocyk
- Laboratory of Pharmacology and Brain Biostructure, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland.
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Early life adversity alters the developmental profiles of addiction-related prefrontal cortex circuitry. Brain Sci 2013; 3:143-58. [PMID: 24961311 PMCID: PMC4061828 DOI: 10.3390/brainsci3010143] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 12/11/2012] [Accepted: 01/24/2013] [Indexed: 01/21/2023] Open
Abstract
Early adverse experience is a well-known risk factor for addictive behaviors later in life. Drug addiction typically manifests during adolescence in parallel with the later-developing prefrontal cortex (PFC). While it has been shown that dopaminergic modulation within the PFC is involved in addiction-like behaviors, little is known about how early adversity modulates its development. Here, we report that maternal separation stress (4 h per day between postnatal days 2–20) alters the development of the prelimbic PFC. Immunofluorescence and confocal microscopy revealed differences between maternally-separated and control rats in dopamine D1 and D2 receptor expression during adolescence, and specifically the expression of these receptors on projection neurons. In control animals, D1 and D2 receptors were transiently increased on all glutamatergic projection neurons, as well as specifically on PFC→nucleus accumbens projection neurons (identified with retrograde tracer). Maternal separation exacerbated the adolescent peak in D1 expression and blunted the adolescent peak in D2 expression on projection neurons overall. However, neurons retrogradely traced from the accumbens expressed lower levels of D1 during adolescence after maternal separation, compared to controls. Our findings reveal microcircuitry-specific changes caused by early life adversity that could help explain heightened vulnerability to drug addiction during adolescence.
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Evidence for a neuroinflammatory mechanism in delayed effects of early life adversity in rats: relationship to cortical NMDA receptor expression. Brain Behav Immun 2013. [PMID: 23207107 DOI: 10.1016/j.bbi.2012.11.012] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Postnatal maternal separation in rats causes a reduction of GABAergic parvalbumin-containing interneurons in the prefrontal cortex that first occurs in adolescence. This parvalbumin loss can be prevented by pre-adolescent treatment with a non-steroidal anti-inflammatory drug that also protects against excitotoxicity. Therefore, the neuropsychiatric disorders associated with early life adversity and interneuron dysfunction may involve neuroinflammatory processes and/or aberrant glutamatergic activity. Here, we aimed to determine whether delayed parvalbumin loss after maternal separation was due to inflammatory activity, and whether central administration of the anti-inflammatory cytokine interleukin (IL)-10 could protect against such loss. We also investigated the effects of maternal separation and IL-10 treatment on cortical NMDA receptor expression. Male rat pups were isolated for 4h/day between postnatal days 2-20. IL-10 was administered intracerebroventricularly through an indwelling cannula between P30 and 38. Adolescent prefrontal cortices were analyzed using Western blotting and immunohistochemistry for parvalbumin and NMDA NR2A subunit expression. We demonstrate that central IL-10 administration during pre-adolescence protects maternally separated animals from parvalbumin loss in adolescence. Linear regression analyses revealed that increased circulating levels of the pro-inflammatory cytokines IL-1β and IL-6 predicted lowered parvalbumin levels in maternally separated adolescents. Maternal separation also increases cortical expression of the NR2A NMDA receptor subunit in adolescence, which is prevented by IL-10 treatment. These data suggest that inflammatory damage to parvalbumin interneurons may occur via aberrant glutamatergic activity in the prefrontal cortex. Our findings provide a novel interactive mechanism between inflammation and neural dysfunction that helps explain deleterious effects of early life adversity on prefrontal cortex interneurons.
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Baudin A, Blot K, Verney C, Estevez L, Santamaria J, Gressens P, Giros B, Otani S, Daugé V, Naudon L. Maternal deprivation induces deficits in temporal memory and cognitive flexibility and exaggerates synaptic plasticity in the rat medial prefrontal cortex. Neurobiol Learn Mem 2012; 98:207-14. [PMID: 22922490 DOI: 10.1016/j.nlm.2012.08.004] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/27/2012] [Accepted: 08/12/2012] [Indexed: 01/18/2023]
Abstract
Early life adverse events can lead to structural and functional impairments in the prefrontal cortex (PFC). Here, we investigated whether maternal deprivation (MD) alters PFC-dependent executive functions, neurons and astrocytes number and synaptic plasticity in adult male Long-Evans rats. The deprivation protocol consisted of a daily separation of newborn Long-Evans pups from their mothers and littermates 3h/day postnatal day 1-14. Cognitive performances were assessed in adulthood using the temporal order memory task (TMT) and the attentional set-shifting task (ASST) that principally implicates the PFC and the Morris water maze task (WMT) that does not essentially rely on the PFC. The neurons and astrocytes of the prelimbic (PrL) area of the medial PFC (mPFC) were immunolabelled respectively with anti-NeuN and anti-GFAP antibodies and quantified by stereology. The field potentials evoked by electrical stimulation of ventral hippocampus (ventral HPC) were recorded in vivo in the PrL area. In adulthood, MD produced cognitive deficits in two PFC-dependent tasks, the TMT and ASST, but not in the WMT. In parallel, MD induced in the prelimbic area of the medial PFC an upregulation of long-term potentiation (LTP), without any change in the number of neurons and astrocytes. We provide evidence that MD leads in adults to an alteration of the cognitive abilities dependent on the PFC, and to an exaggerated synaptic plasticity in this region. We suggest that this latter phenomenon may contribute to the impairments in the cognitive tasks.
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Affiliation(s)
- Aurélie Baudin
- INSERM, UMRs, Physiopathologie des Maladies du Système Nerveux Central, Paris, France
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Brenhouse HC, Andersen SL. Nonsteroidal anti-inflammatory treatment prevents delayed effects of early life stress in rats. Biol Psychiatry 2011; 70:434-40. [PMID: 21679927 PMCID: PMC5237809 DOI: 10.1016/j.biopsych.2011.05.006] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 04/28/2011] [Accepted: 05/05/2011] [Indexed: 12/27/2022]
Abstract
BACKGROUND Early developmental insults can cause dysfunction within parvalbumin (PVB)-containing interneurons in the prefrontal cortex. The neuropsychiatric disorders associated with such dysfunction might involve neuroinflammatory processes. Cyclooxygenase-2 (COX-2) is a key mediator of inflammation and is therefore a potential target for preventive treatment. Here, we investigated whether the developmental trajectories of PVB expression and COX-2 induction in the prelimbic region of the prefrontal cortex are altered after maternal separation stress in male rats. METHODS Male rat pups were separated from their mother and littermates for 4 hours/day between postnatal Days 2 and 20. Western blotting and immunohistochemistry were used to analyze PVB and COX-2 expression in the prefrontal cortex and hippocampus. A separate cohort of animals was treated with a COX-2 inhibitor during preadolescence and analyzed for PVB, COX-2, and working memory performance. RESULTS We demonstrate that maternal separation causes a reduction of PVB and an increase in COX-2 expression in the prefrontal cortex in adolescence, with concurrent working memory deficits. Parvalbumin was not affected earlier in development. Prophylactic COX-2 inhibition preadolescence prevents PVB loss and improves working memory deficits induced by maternal separation. CONCLUSIONS These data are the first to show a preventive pharmacological intervention for the delayed effects of early life stress on prefrontal cortex interneurons and working memory. Our results suggest a possible mechanism for the relationship between early life stress and interneuron dysfunction in adolescence.
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Affiliation(s)
- Heather C Brenhouse
- Laboratory for Developmental Neuropharmacology, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, Massachusetts, USA.
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Chocyk A, Przyborowska A, Dudys D, Majcher I, Maćkowiak M, Wędzony K. The impact of maternal separation on the number of tyrosine hydroxylase-expressing midbrain neurons during different stages of ontogenesis. Neuroscience 2011; 182:43-61. [PMID: 21396433 DOI: 10.1016/j.neuroscience.2011.03.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Revised: 03/02/2011] [Accepted: 03/03/2011] [Indexed: 12/19/2022]
Abstract
Early life stressors have life-long functional and anatomical consequences. Though many neurotransmitters are involved in the functional impact of early life stress, dopamine seems to be important because of its roles in motor control, adaptation to stressful conditions, mood, cognition, attention and reward. Thus, in the present study, we investigated the way that early life stress, in the form of maternal separation (MS), affects the populations of tyrosine hydroxylase-immunoreactive (TH-IR) dopaminergic neurons in rat midbrain structures during ontogenesis. We included in the study the sub-regions of the substantia nigra (SN) and the ventral tegmental area (VTA). In both the control and MS rats, we found that the estimated total number of TH-expressing neurons fluctuated during ontogenesis. Moreover, MS influenced the number of TH-IR cells, especially in the SN pars reticulata (SNr) and VTA. Shortly after the termination of MS, on postnatal day (PND) 15, a decrease in the estimated total number of TH-IR neurons was observed in the SNr and VTA (in both males and females). On PND 35, MS caused a transient increase in the number of TH-IR cells only in the SNr of female rats. On PND 70, MS affected the number of TH-IR neurons in the VTA of females; specifically, an increase in the number of these cells was observed. Additionally, MS did not alter TH-IR cell sizes or the total levels of TH (measured by Western blot analysis) in the SN and VTA for all stages of ontogenesis in both males and females. The results from the study herein indicate that early life stress has enduring effects on the populations of midbrain TH-expressing dopaminergic neurons (especially in female rats), which are critically important for dopamine-regulated brain function throughout ontogenesis.
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Affiliation(s)
- A Chocyk
- Laboratory of Pharmacology and Brain Biostructure, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland.
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