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Wright CJ, Milosavljevic S, Pocivavsek A. The stress of losing sleep: Sex-specific neurobiological outcomes. Neurobiol Stress 2023; 24:100543. [PMID: 37252645 PMCID: PMC10209346 DOI: 10.1016/j.ynstr.2023.100543] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 03/20/2023] [Accepted: 05/06/2023] [Indexed: 05/31/2023] Open
Abstract
Sleep is a vital and evolutionarily conserved process, critical to daily functioning and homeostatic balance. Losing sleep is inherently stressful and leads to numerous detrimental physiological outcomes. Despite sleep disturbances affecting everyone, women and female rodents are often excluded or underrepresented in clinical and pre-clinical studies. Advancing our understanding of the role of biological sex in the responses to sleep loss stands to greatly improve our ability to understand and treat health consequences of insufficient sleep. As such, this review discusses sex differences in response to sleep deprivation, with a focus on the sympathetic nervous system stress response and activation of the hypothalamic-pituitary-adrenal (HPA) axis. We review sex differences in several stress-related consequences of sleep loss, including inflammation, learning and memory deficits, and mood related changes. Focusing on women's health, we discuss the effects of sleep deprivation during the peripartum period. In closing, we present neurobiological mechanisms, including the contribution of sex hormones, orexins, circadian timing systems, and astrocytic neuromodulation, that may underlie potential sex differences in sleep deprivation responses.
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Affiliation(s)
| | | | - Ana Pocivavsek
- Corresponding author. Pharmacology, Physiology, and Neuroscience, USC School of Medicine, Columbia, SC, 29208, USA.
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2
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Parekh SV, Adams LO, Barkell GA, Lysle DT. Sex-differences in anxiety, neuroinflammatory markers, and enhanced fear learning following chronic heroin withdrawal. Psychopharmacology (Berl) 2023; 240:347-359. [PMID: 36633660 PMCID: PMC9879843 DOI: 10.1007/s00213-023-06310-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 12/31/2022] [Indexed: 01/13/2023]
Abstract
Post-traumatic stress disorder (PTSD) and opioid use disorder (OUD) are comorbid in clinical populations. However, both pre-clinical and clinical studies of these co-occurring disorders have disproportionately represented male subjects, limiting the applicability of these findings. Our previous work has identified chronic escalating heroin administration and withdrawal can produce enhanced fear learning. This behavior is associated with an increase in dorsal hippocampal (DH) interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and glial fibrillary acidic protein (GFAP) immunoreactivity. Further, we have shown that these increases in IL-1β and TNF-α are mechanistically necessary for the development of enhanced fear learning. Although these are exciting findings, this paradigm has only been studied in males. The current studies aim to examine sex differences in the behavioral and neuroimmune effects of chronic heroin withdrawal and future enhanced fear learning. In turn, we determined that chronic escalating heroin administration can produce withdrawal in female rats comparable to male rats. Subsequently, we examined the consequence of heroin withdrawal on future enhanced fear learning and IL-1β, TNF-α, and GFAP immunoreactivity. Strikingly, we identified sex differences in these neuroimmune measures, as chronic heroin administration and withdrawal does not produce enhanced fear learning or immunoreactivity changes in females. Moreover, we determined whether heroin withdrawal produces short-term and long-term anxiety behaviors in both female and males. Collectively, these novel experiments are the first to test whether heroin withdrawal can sensitize future fear learning, produce neurobiological changes, and cause short-term and long-term anxiety behaviors in female rats.
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Affiliation(s)
- Shveta V. Parekh
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, CB#3720, Chapel Hill, NC 27599-3270 USA
| | - Lydia O. Adams
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, CB#3720, Chapel Hill, NC 27599-3270 USA
| | - Gillian A. Barkell
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, CB#3720, Chapel Hill, NC 27599-3270 USA
| | - Donald T. Lysle
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, CB#3720, Chapel Hill, NC 27599-3270 USA
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3
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Wegener AJ, Neigh GN. Animal Models of Anxiety and Depression: Incorporating the Underlying Mechanisms of Sex Differences in Macroglia Biology. Front Behav Neurosci 2021; 15:780190. [PMID: 34955780 PMCID: PMC8695436 DOI: 10.3389/fnbeh.2021.780190] [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: 09/20/2021] [Accepted: 11/11/2021] [Indexed: 11/13/2022] Open
Abstract
Animal models have been utilized to explore the mechanisms by which mood disorders develop. Ethologically based stress paradigms are used to induce behavioral responses consistent with those observed in humans suffering from anxiety and depression. While mood disorders are more often diagnosed in women, animal studies are more likely to be carried out in male rodents. However, understanding the mechanisms behind anxiety- and depressive-like behaviors in both sexes is necessary to increase the predictive and construct validity of the models and identify therapeutic targets. To understand sex differences following stress, we must consider how all cell types within the central nervous system are influenced by the neuroendocrine system. This review article discusses the effects of stress and sex steroids on the macroglia: astrocytes and oligodendrocytes. Glia are involved in shaping the synapse through the regulation of neurotransmitter levels and energy resources, making them essential contributors to neural dynamics following stress. As the role of glia in neuromodulation has become more apparent, studies exploring the mechanisms by which glia are altered by stress and steroids will provide insight into sex differences in animal models. These insights will facilitate the optimization of animal models of psychiatric disorders and development of future therapeutic targets.
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Affiliation(s)
- Amy J Wegener
- Department of Anatomy & Neurobiology, Virginia Commonwealth University, Richmond, VA, United States
| | - Gretchen N Neigh
- Department of Anatomy & Neurobiology, Virginia Commonwealth University, Richmond, VA, United States
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4
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Spatio-temporal heterogeneity in hippocampal metabolism in control and epilepsy conditions. Proc Natl Acad Sci U S A 2021; 118:2013972118. [PMID: 33692123 DOI: 10.1073/pnas.2013972118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The hippocampus's dorsal and ventral parts are involved in different operative circuits, the functions of which vary in time during the night and day cycle. These functions are altered in epilepsy. Since energy production is tailored to function, we hypothesized that energy production would be space- and time-dependent in the hippocampus and that such an organizing principle would be modified in epilepsy. Using metabolic imaging and metabolite sensing ex vivo, we show that the ventral hippocampus favors aerobic glycolysis over oxidative phosphorylation as compared to the dorsal part in the morning in control mice. In the afternoon, aerobic glycolysis is decreased and oxidative phosphorylation increased. In the dorsal hippocampus, the metabolic activity varies less between these two times but is weaker than in the ventral. Thus, the energy metabolism is different along the dorsoventral axis and changes as a function of time in control mice. In an experimental model of epilepsy, we find a large alteration of such spatiotemporal organization. In addition to a general hypometabolic state, the dorsoventral difference disappears in the morning, when seizure probability is low. In the afternoon, when seizure probability is high, the aerobic glycolysis is enhanced in both parts, the increase being stronger in the ventral area. We suggest that energy metabolism is tailored to the functions performed by brain networks, which vary over time. In pathological conditions, the alterations of these general rules may contribute to network dysfunctions.
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5
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Mazaré N, Oudart M, Moulard J, Cheung G, Tortuyaux R, Mailly P, Mazaud D, Bemelmans AP, Boulay AC, Blugeon C, Jourdren L, Le Crom S, Rouach N, Cohen-Salmon M. Local Translation in Perisynaptic Astrocytic Processes Is Specific and Changes after Fear Conditioning. Cell Rep 2021; 32:108076. [PMID: 32846133 PMCID: PMC7450274 DOI: 10.1016/j.celrep.2020.108076] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 07/08/2020] [Accepted: 08/05/2020] [Indexed: 12/14/2022] Open
Abstract
Local translation is a conserved mechanism conferring cells the ability to quickly respond to local stimuli. In the brain, it has been recently reported in astrocytes, whose fine processes contact blood vessels and synapses. Yet the specificity and regulation of astrocyte local translation remain unknown. We study hippocampal perisynaptic astrocytic processes (PAPs) and show that they contain the machinery for translation. Using a refined immunoprecipitation technique, we characterize the entire pool of ribosome-bound mRNAs in PAPs and compare it with the one expressed in the whole astrocyte. We find that a specific pool of mRNAs is highly polarized at the synaptic interface. These transcripts encode an unexpected molecular repertoire, composed of proteins involved in iron homeostasis, translation, cell cycle, and cytoskeleton. Remarkably, we observe alterations in global RNA distribution and ribosome-bound status of some PAP-enriched transcripts after fear conditioning, indicating the role of astrocytic local translation in memory and learning. Local translation occurs in perisynaptic astrocytic processes (PAPs) The repertoire of ribosome-bound mRNAs enriched in hippocampal PAPs is specific RNA distribution and local translation change in PAPs after fear conditioning
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Affiliation(s)
- Noémie Mazaré
- Physiology and Physiopathology of the Gliovascular Unit Research Group, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris, France; Doctoral School No. 158, Pierre and Marie Curie University, 75005 Paris, France
| | - Marc Oudart
- Physiology and Physiopathology of the Gliovascular Unit Research Group, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris, France; Doctoral School No. 158, Pierre and Marie Curie University, 75005 Paris, France
| | - Julien Moulard
- Doctoral School No. 158, Pierre and Marie Curie University, 75005 Paris, France; Neuroglial Interactions in Cerebral Physiopathology Research Group, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris, France
| | - Giselle Cheung
- Neuroglial Interactions in Cerebral Physiopathology Research Group, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris, France
| | - Romain Tortuyaux
- Physiology and Physiopathology of the Gliovascular Unit Research Group, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris, France
| | - Philippe Mailly
- Orion Imaging Facility, Center for Interdisciplinary Research in Biology (CIRB), College de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris, France
| | - David Mazaud
- Neuroglial Interactions in Cerebral Physiopathology Research Group, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris, France
| | - Alexis-Pierre Bemelmans
- CEA, DRF, Institut de Biologie François Jacob, Molecular Imaging Research Center (MIRCen), 92265 Fontenay-aux-Roses, France; CNRS, CEA, Université Paris-Sud, Université Paris-Saclay, Neurodegenerative Diseases Laboratory (UMR9199), 92265 Fontenay-aux-Roses, France
| | - Anne-Cécile Boulay
- Physiology and Physiopathology of the Gliovascular Unit Research Group, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris, France
| | - Corinne Blugeon
- Genomic Facility, Institut de Biologie de l'ENS (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France
| | - Laurent Jourdren
- Genomic Facility, Institut de Biologie de l'ENS (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France
| | - Stéphane Le Crom
- Genomic Facility, Institut de Biologie de l'ENS (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France; Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratory of Computational and Quantitative Biology (LCQB), 75005 Paris, France
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiopathology Research Group, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris, France
| | - Martine Cohen-Salmon
- Physiology and Physiopathology of the Gliovascular Unit Research Group, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris, France.
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6
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Reddy DS, Thompson W, Calderara G. Molecular mechanisms of sex differences in epilepsy and seizure susceptibility in chemical, genetic and acquired epileptogenesis. Neurosci Lett 2021; 750:135753. [PMID: 33610673 PMCID: PMC7994197 DOI: 10.1016/j.neulet.2021.135753] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 02/03/2021] [Accepted: 02/14/2021] [Indexed: 02/07/2023]
Abstract
This article provides a succinct overview of sex differences in epilepsy and putative molecular mechanisms underlying sex differences in seizure susceptibility in chemical, genetic, and acquired epileptogenesis. The susceptibility to excitability episodes and occurrence of epileptic seizures are generally higher in men than women. The precise molecular mechanisms remain unclear, but differences in regional morphology and neural circuits in men and women may explain differential vulnerability to seizures and epileptogenic cascades. Changes in seizure sensitivity can be attributed to steroid hormones, including fluctuations in neurosteroids as well as neuroplasticity in their receptor signaling systems. Other potential neurobiological bases for sex differences in epilepsies include differences in brain development, neurogenesis, neuronal chloride homeostasis, and neurotrophic and glial responses. In catamenial epilepsy, a gender-specific neuroendocrine condition, epileptic seizures are most often clustered around a specific menstrual period in adult women. A deeper understanding of the molecular and neural network basis of sex differences in seizures and response to antiepileptic drugs is highly warranted for designing effective, sex-specific therapies for epilepsy, epileptogenesis, and seizure disorders.
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Affiliation(s)
- Doodipala Samba Reddy
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University College of Medicine, Bryan, TX, United States.
| | - Wesley Thompson
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University College of Medicine, Bryan, TX, United States
| | - Gianmarco Calderara
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University College of Medicine, Bryan, TX, United States
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7
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Christian CA, Reddy DS, Maguire J, Forcelli PA. Sex Differences in the Epilepsies and Associated Comorbidities: Implications for Use and Development of Pharmacotherapies. Pharmacol Rev 2021; 72:767-800. [PMID: 32817274 DOI: 10.1124/pr.119.017392] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The epilepsies are common neurologic disorders characterized by spontaneous recurrent seizures. Boys, girls, men, and women of all ages are affected by epilepsy and, in many cases, by associated comorbidities as well. The primary courses of treatment are pharmacological, dietary, and/or surgical, depending on several factors, including the areas of the brain affected and the severity of the epilepsy. There is a growing appreciation that sex differences in underlying brain function and in the neurobiology of epilepsy are important factors that should be accounted for in the design and development of new therapies. In this review, we discuss the current knowledge on sex differences in epilepsy and associated comorbidities, with emphasis on those aspects most informative for the development of new pharmacotherapies. Particular focus is placed on sex differences in the prevalence and presentation of various focal and generalized epilepsies; psychiatric, cognitive, and physiologic comorbidities; catamenial epilepsy in women; sex differences in brain development; the neural actions of sex and stress hormones and their metabolites; and cellular mechanisms, including brain-derived neurotrophic factor signaling and neuronal-glial interactions. Further attention placed on potential sex differences in epilepsies, comorbidities, and drug effects will enhance therapeutic options and efficacy for all patients with epilepsy. SIGNIFICANCE STATEMENT: Epilepsy is a common neurological disorder that often presents together with various comorbidities. The features of epilepsy and seizure activity as well as comorbid afflictions can vary between men and women. In this review, we discuss sex differences in types of epilepsies, associated comorbidities, pathophysiological mechanisms, and antiepileptic drug efficacy in both clinical patient populations and preclinical animal models.
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Affiliation(s)
- Catherine A Christian
- Department of Molecular and Integrative Physiology, Neuroscience Program, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois (C.A.C.); Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas (D.S.R.); Neuroscience Department, Tufts University School of Medicine, Boston, Massachusetts (J.M.); and Departments of Pharmacology and Physiology and Neuroscience, Georgetown University, Washington, D.C. (P.A.F.)
| | - Doodipala Samba Reddy
- Department of Molecular and Integrative Physiology, Neuroscience Program, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois (C.A.C.); Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas (D.S.R.); Neuroscience Department, Tufts University School of Medicine, Boston, Massachusetts (J.M.); and Departments of Pharmacology and Physiology and Neuroscience, Georgetown University, Washington, D.C. (P.A.F.)
| | - Jamie Maguire
- Department of Molecular and Integrative Physiology, Neuroscience Program, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois (C.A.C.); Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas (D.S.R.); Neuroscience Department, Tufts University School of Medicine, Boston, Massachusetts (J.M.); and Departments of Pharmacology and Physiology and Neuroscience, Georgetown University, Washington, D.C. (P.A.F.)
| | - Patrick A Forcelli
- Department of Molecular and Integrative Physiology, Neuroscience Program, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois (C.A.C.); Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas (D.S.R.); Neuroscience Department, Tufts University School of Medicine, Boston, Massachusetts (J.M.); and Departments of Pharmacology and Physiology and Neuroscience, Georgetown University, Washington, D.C. (P.A.F.)
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8
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Jiang Q, Xu H, Yan J, Xu Q, Zheng Y, Li C, Zhao L, Gao H, Zheng H. Sex-specific metabolic alterations in the type 1 diabetic brain of mice revealed by an integrated method of metabolomics and mixed-model. Comput Struct Biotechnol J 2020; 18:2063-2074. [PMID: 32802278 PMCID: PMC7419581 DOI: 10.1016/j.csbj.2020.07.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 12/12/2022] Open
Abstract
Type 1 diabetes (T1D) can cause brain region-specific metabolic disorders, but whether gender influences T1D-related brain metabolic changes is rarely reported. Therefore, here we examined metabolic changes in six different brain regions of male and female mice under normal and T1D conditions using an integrated method of NMR-based metabolomics and linear mixed-model, and aimed to explore sex-specific metabolic changes from normal to T1D. The results demonstrate that metabolic differences occurred in all brain regions between two genders, while the hippocampal metabolism is more likely to be affected by T1D. At the 4th week after streptozotocin treatment, brain metabolic disorders mainly occurred in the cortex and hippocampus in female T1D mice, but the striatum and hippocampus in male T1D mice. In addition, anaerobic glycolysis was significantly altered in male mice, mainly in the striatum, midbrain, hypothalamus and hippocampus, but not in female mice. We also found that female mice exhibited a hypometabolism status relative to male mice from normal to T1D. Collectively, this study suggests that T1D affected brain region-specific metabolic alterations in a sex-specific manner, and may provide a metabolic view on diabetic brain diseases between genders.
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Key Words
- ADP, adenosine diphosphate
- AMP, adenosine monophosphate
- Ala, alanine
- Asp, aspartate
- Cho, choline
- Cortex
- Cre/pCre, creatine/phosphocreatine
- Diabetes
- GABA, γ-Aminobutyric acid
- Gender
- Gln, glutamine
- Glu, glutamate
- Gly, glycine
- Hippocampus
- IMP, inosine monophosphate
- Ino, inosine
- Lac, lactate
- Metabolomics
- Myo, myo-inositol
- NAA, N-acetylaspartate
- NAD+, nicotinamide adeninedinucleotide
- Neurotransmitter
- Suc, succinate
- Tau, taurine
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Affiliation(s)
- Qiaoying Jiang
- Institute of Metabonomics & Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Hangying Xu
- Institute of Metabonomics & Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Junjie Yan
- Institute of Metabonomics & Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Qingqing Xu
- Institute of Metabonomics & Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Yafei Zheng
- Institute of Metabonomics & Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Chen Li
- Institute of Metabonomics & Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Liangcai Zhao
- Institute of Metabonomics & Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Hongchang Gao
- Institute of Metabonomics & Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Hong Zheng
- Institute of Metabonomics & Medical NMR, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
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9
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Abstract
The hippocampus is central to spatial learning and stress responsiveness, both of which differ in form and function in males versus females, yet precisely how the hippocampus contributes to these sex differences is largely unknown. In reproductively mature individuals, sex differences in the steroid hormone milieu undergirds many sex differences in hippocampal-related endpoints. However, there is also evidence for developmental programming of adult hippocampal function, with a central role for androgens as well as their aromatized byproduct, estrogens. These include sex differences in cell genesis, synapse formation, dendritic arborization, and excitatory/inhibitory balance. Enduring effects of steroid hormone modulation occur during two developmental epochs, the first being the classic perinatal critical period of sexual differentiation of the brain and the other being adolescence and the associated hormonal changes of puberty. The cellular mechanisms by which steroid hormones enduringly modify hippocampal form and function are poorly understood, but we here review what is known and highlight where attention should be focused.
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10
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Prenatal Androgenization Induces Anxiety-Like Behavior in Female Rats, Associated with Reduction of Inhibitory Interneurons and Increased BDNF in Hippocampus and Cortex. BIOMED RESEARCH INTERNATIONAL 2019; 2019:3426092. [PMID: 31281833 PMCID: PMC6590533 DOI: 10.1155/2019/3426092] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 04/16/2019] [Indexed: 12/22/2022]
Abstract
Anxiety is one of the most frequent psychiatric disorders. Despite the fact that most studies describe an anxiolytic effect of testosterone, hyperandrogenemia in mothers is assumed to be related to an increased risk of mood disorders in their offspring. An increasing body of scientific evidence suggests that an altered expression of interneuronal markers of the hippocampus may be the cause of anxiety. The aim of this study was to examine the influence of maternal hyperandrogenemia on behavioral parameters of anxiety-like behavior, neuropeptide Y (NPY) and parvalbumin (PV) expression in the hippocampus, and the level of the brain-derived neurotrophic factor (BDNF) in the hippocampus and cerebral cortex. Pregnant female Wistar albino rats were treated with testosterone undecanoate on the 20th day of gestation. Anxiety-like behavior in adult female offspring was evaluated by the elevated plus maze test and the open field. The number of PV and NPY immunoreactive cells in the hippocampus was determined immunohistochemically. The level of BDNF expression in the hippocampus and cerebral cortex was analyzed with the Western blot test. Prenatal hyperandrogenization increased anxiety-like behavior in female offspring and decreased expression of NPY+ and PV+ in the CA1 region of the hippocampus as compared to the control group. BDNF expression in the hippocampus and cerebral cortex of prenatally androgenized female offspring was significantly increased in comparison with the controls. Prenatal hyperandrogenization may be the cause of anxiety-like behavior in female offspring. Decrease in NPY and PV expression in the hippocampus may explain the possible mechanism of hyperandrogenization induced anxiety.
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11
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Turano A, Osborne BF, Schwarz JM. Sexual Differentiation and Sex Differences in Neural Development. Curr Top Behav Neurosci 2018; 43:69-110. [PMID: 29967999 DOI: 10.1007/7854_2018_56] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Sex determination occurs at the moment of conception, as a result of XX or XY chromosome pairing. From that point, the body undergoes the process of sexual differentiation, inducing the development of physical characteristics that are easily distinguishable between the sexes and are often reflected in one's physical appearance and gender identity. Although less apparent, the brain also undergoes sexual differentiation. Sex differences in the brain are organized during a critical period of neural development and have an instrumental role in determining the physiology and behavior of an individual throughout the lifespan. Understanding the extent of sex differences in neurodevelopment also influences our understanding of the potential risk for a number of neurodevelopmental, neurological, and mental health disorders that exhibit strong sex biases. Advances made in our understanding of sexually dimorphic brain nuclei, sex differences in neural cell communication, and sex differences in the communication between the brain and peripheral organs are all research fields that have provided valuable information related to the physiological and behavioral outcomes of sex differences in brain development. More recently, investigations into the impact of epigenetic mechanisms on sexual differentiation of the brain have indicated that changes in gene expression, via epigenetic modifications, also contribute to sexual differentiation of the developing brain. Still, there are a number of important questions and ideas that have arisen from our current understanding of sex differences in neurodevelopmental processes that necessitate more time and attention in this field.
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Affiliation(s)
- Alexandra Turano
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, USA
| | - Brittany F Osborne
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, USA
| | - Jaclyn M Schwarz
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, USA.
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12
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Borbélyová V, Domonkos E, Bábíčková J, Tóthová Ľ, Bosý M, Hodosy J, Celec P. No effect of testosterone on behavior in aged Wistar rats. Aging (Albany NY) 2017; 8:2848-2861. [PMID: 27852981 PMCID: PMC5191874 DOI: 10.18632/aging.101096] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 10/28/2016] [Indexed: 11/25/2022]
Abstract
In men, aging is accompanied by a gradual decline in androgen secretion. Studies suggest beneficial effects of endogenous and exogenous testosterone on affective behavior and cognitive functions. The aim of this study was to describe behavioral and cognitive sex differences and to analyze the effects of long-term androgen deficiency in aged male rats. Thirty-months old rats divided into three groups (males, females and males gonadectomized as young adults) underwent a battery of behavioral tests assessing locomotor activity, anxiety, memory, anhedonia, sociability and depression-like behavior. No major effect of gonadectomy was found in any of the analyzed behavioral measures in male rats. The only consistent sex difference was confirmed in depression-like behavior with longer immobility time observed in males. In an interventional experiment, a single dose of testosterone had no effect on gonadectomized male and female rats in the forced swim test. In contrast to previous studies this comprehensive behavioral phenotyping of aged rats revealed no major role of endogenous testosterone. Based on our results long-term hypogonadism does not alter the behavior of aged male rats, neither does acute testosterone treatment. Whether these findings have any consequences on androgen replacement therapy in aged men remains to be elucidated.
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Affiliation(s)
- Veronika Borbélyová
- Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, 811 08 Bratislava, Slovakia
| | - Emese Domonkos
- Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, 811 08 Bratislava, Slovakia
| | - Janka Bábíčková
- Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, 811 08 Bratislava, Slovakia.,Biomedical Research Center, Slovak Academy of Sciences, 831 01 Bratislava, Slovakia
| | - Ľubomíra Tóthová
- Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, 811 08 Bratislava, Slovakia.,Biomedical Research Center, Slovak Academy of Sciences, 831 01 Bratislava, Slovakia
| | - Martin Bosý
- Department of Animal Physiology and Ethology, Faculty of Natural Sciences, Comenius University, 842 15 Bratislava, Slovakia
| | - Július Hodosy
- Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, 811 08 Bratislava, Slovakia.,Institute of Physiology, Faculty of Medicine, Comenius University, 813 72 Bratislava, Slovakia.,Biomedical Research Center, Slovak Academy of Sciences, 831 01 Bratislava, Slovakia
| | - Peter Celec
- Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, 811 08 Bratislava, Slovakia.,Institute of Pathophysiology, Faculty of Medicine, Comenius University, 811 08 Bratislava, Slovakia.,Department of Molecular Biology, Faculty of Natural Sciences, Comenius University, 842 15 Bratislava, Slovakia.,Biomedical Research Center, Slovak Academy of Sciences, 831 01 Bratislava, Slovakia
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13
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Filová B, Ostatníková D, Celec P, Hodosy J. The effect of testosterone on the formation of brain structures. Cells Tissues Organs 2013; 197:169-77. [PMID: 23306974 DOI: 10.1159/000345567] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/01/2012] [Indexed: 11/19/2022] Open
Abstract
It has been confirmed in several studies that testosterone can significantly affect brain development. Following metabolism of this hormone by 5α-reductase to dihydrotestosterone, testosterone may act via androgen receptors, or after conversion by aromatase to estradiol, it may act via estrogen receptors. The parts of the brain which are changed under the influence of sex hormones are known as sexually dimorphic nuclei, especially in the preoptic area of the hypothalamus. Nevertheless, evidence suggests that testosterone also influences the structure of the hippocampus, specifically CA1 and CA3 areas of the hippocampus, as well as the amygdala. These brain areas are designed to convert information from short-term into long-term memory. In this review, we summarize the effects of testosterone on the organization of brain structures with respect to spatial cognitive abilities in small rodents.
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Affiliation(s)
- Barbora Filová
- Institute of Molecular Biomedicine, Comenius University, Bratislava, Slovakia
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14
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Learning impairment caused by intra-CA1 microinjection of testosterone increases the number of astrocytes. Behav Brain Res 2010; 208:30-7. [DOI: 10.1016/j.bbr.2009.11.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2009] [Revised: 10/26/2009] [Accepted: 11/01/2009] [Indexed: 11/18/2022]
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15
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Sexually dimorphic c-Fos expression following spatial working memory in young and adult rats. Physiol Behav 2009; 98:307-17. [PMID: 19545582 DOI: 10.1016/j.physbeh.2009.06.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Revised: 06/05/2009] [Accepted: 06/11/2009] [Indexed: 11/22/2022]
Abstract
The sex differences in the functional contribution of brain substrates were explored following acquisition of a spatial working memory task using quantification of c-Fos protein. Rats of both sexes were trained during adolescence and adulthood in Morris water maze using a hidden escape platform with different daily location. Two control groups for each sex and age were added to explore the c-Fos activation not specific to the memory process. These were a free-swimming group (yoked control) and a handled control (CO) group. Behaviorally, no age differences were found in number of days required by males to acquire the task, but females showed a delay in acquisition during adolescence (P30) that improved in adulthood (P90). Both sexes showed a learning-related increase in Fos immunoreactivity in the anterodorsal and anteroventral thalamus and medial and lateral mammillary nuclei during adolescence. Higher levels of learning-related Fos immunoreactivity were found in the infralimbic cortex, CA3 and CA1 only in females. During adulthood the common activated region was the prelimbic cortex with the addition of the infralimbic cortex in the male group and the lateral mammillary nucleus in the female group. These results indicated sex and age differences in brain functioning following working memory task. However, they could not be necessarily linked with differences in performance since similar results were found between males and females during adulthood. The activation of common and interrelated structures suggests that these structures are involved in spatial processing but it also highlights the relevance of developmental changes for understanding the memory process.
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Méndez-López M, Méndez M, López L, Arias JL. Spatial working memory in Wistar rats: Brain sex differences in metabolic activity. Brain Res Bull 2009; 79:187-92. [DOI: 10.1016/j.brainresbull.2009.02.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Revised: 02/16/2009] [Accepted: 02/19/2009] [Indexed: 10/21/2022]
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17
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Johnson RT, Breedlove SM, Jordan CL. Sex differences and laterality in astrocyte number and complexity in the adult rat medial amygdala. J Comp Neurol 2008; 511:599-609. [PMID: 18853427 PMCID: PMC2592304 DOI: 10.1002/cne.21859] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The posterodorsal portion of the medial amygdala (MePD) is sexually dimorphic in several rodent species. In several other brain nuclei, astrocytes change morphology in response to steroid hormones. We visualized MePD astrocytes using glial-fibrillary acidic protein (GFAP) immunocytochemistry. We compared the number and process complexity of MePD astrocytes in adult wildtype male and female rats and testicular feminized mutant (TFM) male rats that lack functional androgen receptors (ARs) to determine whether MePD astrocytes are sexually differentiated and whether ARs have a role. Unbiased stereological methods revealed laterality and sex differences in MePD astrocyte number and complexity. The right MePD contained more astrocytes than the left in all three genotypes, and the number of astrocytes was also sexually differentiated in the right MePD, with males having more astrocytes than females. In contrast, the left MePD contained more complex astrocytes than did the right MePD in all three genotypes, and males had more complex astrocytes than females in this hemisphere. TFM males were comparable to wildtype females, having fewer astrocytes on the right and simpler astrocytes on the left than do wildtype males. Taken together, these results demonstrate that astrocytes are sexually dimorphic in the adult MePD and that the nature of the sex difference is hemisphere-dependent: a sex difference in astrocyte number in the right MePD and a sex difference in astrocyte complexity in the left MePD. Moreover, functional ARs appear to be critical in establishing these sex differences in MePD astrocyte morphology.
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Affiliation(s)
- Ryan T Johnson
- Neuroscience Program, Michigan State University, East Lansing, Michigan 48824-1101, USA.
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18
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Zhang JM, Konkle ATM, Zup SL, McCarthy MM. Impact of sex and hormones on new cells in the developing rat hippocampus: a novel source of sex dimorphism? Eur J Neurosci 2008; 27:791-800. [PMID: 18333959 DOI: 10.1111/j.1460-9568.2008.06073.x] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The hippocampus is a key brain region regulating complex cognitive and emotional responses, and is implicated in the etiology of depressive and anxiety disorders, many of which exhibit some degree of sex difference. The male rat hippocampus is consistently reported to be slightly but significantly larger than the female. The majority of studies on the development of volumetric sex differences have focused on the effects of estradiol (E2), with relatively few focusing on androgens. We examined the impact of both E2 and androgens on newly born cells in the developing rat hippocampus, and report that neonatal males have significantly more 5-bromo-2'-deoxyuridine-5'-monophosphate (BrdU)+ cells than females. Both testosterone (T) and dihydrotestosterone treatment of females significantly increased the number of BrdU+ cells, an effect blocked by the androgen receptor antagonist, flutamide. However, only T significantly increased the number of neuronal nuclear antigen+ neurons in the female rat hippocampus. Interestingly, E2 treatment also increased BrdU+ cells in females, but had no effect on neuron number. Instead, E2 and T significantly increased the number of newly born glial fibrillary acidic protein or glutamine synthetase+ glial cells in females, indicating that androgens and E2 may act independently to achieve distinct endpoints. Quantification of pyknotic cells at two different developmental time points indicates no sex difference in the number of cells dying, suggesting, but not proving, that gonadal steroids are promoting cell genesis.
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Affiliation(s)
- Jian-Min Zhang
- Department of Psychiatry, University of Maryland, Baltimore, School of Medicine, Baltimore, MD 21201, USA.
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19
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Bracchi-Ricard V, Brambilla R, Levenson J, Hu WH, Bramwell A, Sweatt JD, Green EJ, Bethea JR. Astroglial nuclear factor-kappaB regulates learning and memory and synaptic plasticity in female mice. J Neurochem 2007; 104:611-23. [PMID: 17953667 DOI: 10.1111/j.1471-4159.2007.04993.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Astrocytes play a pivotal role in regulating synaptic plasticity and synapse formation. The nuclear factor-kappa B (NF-kappaB) family of transcription factors has recently been demonstrated to be an important modulator of synaptic plasticity and learning/memory. In this study, we investigated the role of astroglial NF-kappaB in synaptic plasticity and learning/memory using transgenic mice over-expressing an N-terminal truncated form of inhibitor of NF-kappaB alpha (IkappaBalpha) in astrocytes (GFAP-IkappaBetaalpha-dn). We demonstrated that female transgenic mice, but not males, have robust deficits in hippocampal and extra-hippocampal-dependent learning and memory. We also determined that there are significant deficits in LTP and expression of metabotropic glutamate receptor 5 and post-synaptic density protein 95 (PSD95) in female transgenic mice. These findings indicate that astroglial NF-kappaB is an important regulator of learning/memory and synaptic plasticity.
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Affiliation(s)
- Valerie Bracchi-Ricard
- The Miami Project to Cure Paralysis, Department of Neurological Surgery, University of Miami School of Medicine, Miami, Florida 33136, USA.
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20
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Stein DG. Sex differences in brain damage and recovery of function: experimental and clinical findings. PROGRESS IN BRAIN RESEARCH 2007; 161:339-51. [PMID: 17618989 DOI: 10.1016/s0079-6123(06)61024-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Until the last decade or so, there was very little systematic examination of sex differences in recovery from brain injury--most of the work was anecdotal or based on very small studies comparing males to females. This chapter reviews some of the physiological, morphological, and functional evidence for sex differences in response to brain injury across the spectrum of development. It also examines more recent data showing that fluctuations in hormonal status during the menstrual and estrous cycle can play a determining role in functional outcome in both normal and brain-injured females, and that these hormonal influences can be measured at both the cellular and behavioral levels.
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Affiliation(s)
- Donald G Stein
- Department of Emergency Medicine, Emory University School of Medicine, Atlanta, GA, USA.
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21
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Martinez FG, Hermel EES, Xavier LL, Viola GG, Riboldi J, Rasia-Filho AA, Achaval M. Gonadal hormone regulation of glial fibrillary acidic protein immunoreactivity in the medial amygdala subnuclei across the estrous cycle and in castrated and treated female rats. Brain Res 2006; 1108:117-26. [PMID: 16842763 DOI: 10.1016/j.brainres.2006.06.014] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2006] [Revised: 05/22/2006] [Accepted: 06/05/2006] [Indexed: 11/17/2022]
Abstract
The medial amygdala (MeA) is a sexually dimorphic area that modulates neuroendocrine and behavioral activities and where gonadal hormones play an important role in neuron-glial and synaptic plasticity. Immunohistochemistry was used to identify the astrocytic marker glial fibrillary acidic protein (GFAP) in the different MeA subnuclei--anterodorsal (MeAD), posterodorsal (MePD) and posteroventral (MePV)--of intact female rats in the different phases of the estrous cycle and in ovariectomized females treated with hormonal substitutive therapy. Data semi-quantified by optical densitometry showed that, in the proestrus phase, the GFAP immunoreactivity (GFAP-ir) was higher when compared to the other phases of the estrous cycle (P < 0.02). GFAP-ir was also higher in the MePD than in the MeAD or in the MePV (P < 0. 02). In ovariectomized females, injections of estradiol alone or estradiol plus progesterone increased GFAP-ir in the MePD and in the MePV (P < 0.001), but not in the MeAD (P > 0.3), when compared to control data. These findings suggest that astrocytic GFAP in the MeA subnuclei can be affected either by physiological levels or by hormonal manipulation of the ovarian steroids, which may contribute to the plasticity of local and integrated functional activities of these brain areas in female rats.
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Affiliation(s)
- Flávia G Martinez
- Programa de Pós-Graduação em Neurociências, ICBS, Universidade Federal do Rio Grande do Sul, R. Sarmento Leite 500, Porto Alegre 90050-170, RS, Brazil
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22
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Blanco E, Picón IM, Miranda R, Begega A, Conejo NM, Arias JL. Astroglial distribution and sexual differences in neural metabolism in mammillary bodies. Neurosci Lett 2006; 395:82-6. [PMID: 16330145 DOI: 10.1016/j.neulet.2005.10.061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Revised: 09/14/2005] [Accepted: 10/24/2005] [Indexed: 12/01/2022]
Abstract
The sexual differences in cerebral nuclei are produced by the organizational and the activational function of gonadal hormones. The different performances by male and female rats in memory tasks requiring use of the mammillary bodies (MBs), could be due to structural and functional sexual dimorphic differences. Our work quantifies the number of glial fibrillary acidic protein immunoreactive (GFAP-IR) astrocytes, and neuronal metabolic activity measured by the cytochrome oxidase (CO) histochemistry in the MBs in rats of both sexes. We find that there is no difference in astroglial number in the medial mammillary nucleus (MMN) and in the lateral mammillary nucleus (LMN) of males, females in estrus and diestrus adult rats. However, we do find statistically significant differences between the sexes in the neuronal oxidative metabolism influenced by the estrous cycle. We, therefore, conclude that there are functional and not structural sex differences in the MBs.
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Affiliation(s)
- Eduardo Blanco
- Laboratorio de Psicobiología, Facultad de Psicología, Universidad de Oviedo, Plaza Feijoo, s/n, CP 33003 Oviedo, Spain.
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23
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Cambras T, López L, Arias JL, Díez-Noguera A. Quantitative changes in neuronal and glial cells in the suprachiasmatic nucleus as a function of the lighting conditions during weaning. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2005; 157:27-33. [PMID: 15939082 DOI: 10.1016/j.devbrainres.2005.02.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Revised: 02/21/2005] [Accepted: 02/28/2005] [Indexed: 11/18/2022]
Abstract
To examine whether lighting conditions during the development of the rat circadian system affect the morphology of the suprachiasmatic nucleus (SCN), three groups of rats were born and maintained until they were 24 days old under constant light (LL), constant darkness (DD) or 24-h light-dark cycles (LD, 12-h light and 12-h darkness). We applied a stereological method to study whether these conditions lead to alterations in the volume of the SCN and changes in the total number of neurons and glial cells. While lighting conditions did not induce differences in the SCN volume, the number of both neurons and glial cells did differ between groups. The DD rats showed the lowest number of neurons. Glial cells were also lower in this group than in the other two groups; however the number of glial cells in LL rats was lower than in LD rats. Moreover, females had more glial cells than males but males and females showed a similar number of neurons. These findings indicate the plasticity of the SCN in response to lighting conditions during the developmental stage.
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Affiliation(s)
- Trinitat Cambras
- Department of Physiology, Faculty of Pharmacy, University of Barcelona, Barcelona, Spain.
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24
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Conejo NM, González-Pardo H, Cimadevilla JM, Argüelles JA, Díaz F, Vallejo-Seco G, Arias JL. Influence of gonadal steroids on the glial fibrillary acidic protein-immunoreactive astrocyte population in young rat hippocampus. J Neurosci Res 2004; 79:488-94. [PMID: 15619230 DOI: 10.1002/jnr.20372] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
It is known that expression of glial fibrillary acidic protein (GFAP) as an astrocyte-specific marker can be regulated by levels of circulating gonadal steroids during postnatal development. In addition, astrocytes play an important role in the physiology of the hippocampus, a brain region considered sexually dimorphic at the neuronal level in rodents. To evaluate the contribution of glial cells to gender-related differences in the hippocampus, we estimated the number of GFAP-immunoreactive (GFAP-IR) astrocytes in the hippocampus (CA1 and CA3 areas, dorsal and ventral regions) of male and female rats aged 30 days. Groups of 30-day-old masculinized females (TP-females; injected with testosterone propionate at birth) and feminized males (FLU-males, castrated and treated with flutamide, an androgen receptor antagonist) were included to assess the effects of gonadal hormones on these hippocampal astrocytes. Using the optical fractionator method, the total number of GFAP-IR cells found in CA1 and CA3 areas was significantly higher in males compared to that in age-matched females. This numerical pattern was reversed in TP-females and FLU-males in both hippocampal areas. In addition, more GFAP-IR cells were found in dorsal hippocampus than in the ventral region in the CA1 area from all experimental groups, whereas this result was found in the CA3 area from males and TP-females. Our results suggest an essential contribution of gonadal hormones to gender differences found in the astrocyte population of the rat hippocampus during development.
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Affiliation(s)
- N M Conejo
- Laboratory of Psychobiology, Faculty of Psychology, University of Oviedo, Spain
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