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Madison FN, Bingman VP, Smulders TV, Lattin CR. A bird's eye view of the hippocampus beyond space: Behavioral, neuroanatomical, and neuroendocrine perspectives. Horm Behav 2024; 157:105451. [PMID: 37977022 DOI: 10.1016/j.yhbeh.2023.105451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 10/27/2023] [Accepted: 11/05/2023] [Indexed: 11/19/2023]
Abstract
Although the hippocampus is one of the most-studied brain regions in mammals, research on the avian hippocampus has been more limited in scope. It is generally agreed that the hippocampus is an ancient feature of the amniote brain, and therefore homologous between the two lineages. Because birds and mammals are evolutionarily not very closely related, any shared anatomy is likely to be crucial for shared functions of their hippocampi. These functions, in turn, are likely to be essential if they have been conserved for over 300 million years. Therefore, research on the avian hippocampus can help us understand how this brain region evolved and how it has changed over evolutionary time. Further, there is a strong research foundation in birds on hippocampal-supported behaviors such as spatial navigation, food caching, and brood parasitism that scientists can build upon to better understand how hippocampal anatomy, network circuitry, endocrinology, and physiology can help control these behaviors. In this review, we summarize our current understanding of the avian hippocampus in spatial cognition as well as in regulating anxiety, approach-avoidance behavior, and stress responses. Although there are still some questions about the exact number of subdivisions in the avian hippocampus and how that might vary in different avian families, there is intriguing evidence that the avian hippocampus might have complementary functional profiles along the rostral-caudal axis similar to the dorsal-ventral axis of the rodent hippocampus, where the rostral/dorsal hippocampus is more involved in cognitive processes like spatial learning and the caudal/ventral hippocampus regulates emotional states, anxiety, and the stress response. Future research should focus on elucidating the cellular and molecular mechanisms - including endocrinological - in the avian hippocampus that underlie behaviors such as spatial navigation, spatial memory, and anxiety-related behaviors, and in so doing, resolve outstanding questions about avian hippocampal function and organization.
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Affiliation(s)
- Farrah N Madison
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Verner P Bingman
- Department of Psychology, J. P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University, Bowling Green, OH 43403, USA
| | - Tom V Smulders
- Centre for Behaviour and Evolution, School of Psychology, Newcastle University, Newcastle upon Tyne NE2 4DR, UK
| | - Christine R Lattin
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70808, USA.
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2
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Immenschuh J, Thalhammer SB, Sundström-Poromaa I, Biegon A, Dumas S, Comasco E. Sex differences in distribution and identity of aromatase gene expressing cells in the young adult rat brain. Biol Sex Differ 2023; 14:54. [PMID: 37658400 PMCID: PMC10474706 DOI: 10.1186/s13293-023-00541-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 08/23/2023] [Indexed: 09/03/2023] Open
Abstract
BACKGROUND Aromatase catalyzes the synthesis of estrogens from androgens. Knowledge on its regional expression in the brain is of relevance to the behavioral implications of these hormones that might be linked to sex differences in mental health. The present study investigated the distribution of cells expressing the aromatase coding gene (Cyp19a1) in limbic regions of young adult rats of both sexes, and characterized the cell types expressing this gene. METHODS Cyp19a1 mRNA was mapped using fluorescent in situ hybridization (FISH). Co-expression with specific cell markers was assessed with double FISH; glutamatergic, gamma-aminobutyric acid (GABA)-ergic, glial, monoaminergic, as well as interneuron markers were tested. Automated quantification of the cells expressing the different genes was performed using CellProfiler. Sex differences in the number of cells expressing Cyp19a1 was tested non-parametrically, with the effect size indicated by the rank-biserial correlation. FDR correction for multiple testing was applied. RESULTS In the male brain, the highest percentage of Cyp19a1+ cells was found in the medial amygdaloid nucleus and the bed nucleus of stria terminalis, followed by the medial preoptic area, the CA2/3 fields of the hippocampus, the cortical amygdaloid nucleus and the amygdalo-hippocampal area. A lower percentage was detected in the caudate putamen, the nucleus accumbens, and the ventromedial hypothalamus. In females, the distribution of Cyp19a1+ cells was similar but at a lower percentage. In most regions, the majority of Cyp19a1+ cells were GABAergic, except for in the cortical-like regions of the amygdala where most were glutamatergic. A smaller fraction of cells co-expressed Slc1a3, suggesting expression of Cyp19a1 in astrocytes; monoaminergic markers were not co-expressed. Moreover, sex differences were detected regarding the identity of Cyp19a1+ cells. CONCLUSIONS Females show overall a lower number of cells expressing Cyp19a1 in the limbic brain. In both sexes, aromatase is expressed in a region-specific manner in GABAergic and glutamatergic neurons. These findings call for investigations of the relevance of sex-specific and region-dependent expression of Cyp19a1 in the limbic brain to sex differences in behavior and mental health.
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Affiliation(s)
- Jana Immenschuh
- Department of Women’s and Children’s Health, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Stefan Bernhard Thalhammer
- Department of Women’s and Children’s Health, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | | | - Anat Biegon
- Department of Radiology and Neurology, Stony Brook University School of Medicine, Stony Brook, NY USA
| | | | - Erika Comasco
- Department of Women’s and Children’s Health, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
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3
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Spool JA, Bergan JF, Remage-Healey L. A neural circuit perspective on brain aromatase. Front Neuroendocrinol 2022; 65:100973. [PMID: 34942232 PMCID: PMC9667830 DOI: 10.1016/j.yfrne.2021.100973] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 12/23/2022]
Abstract
This review explores the role of aromatase in the brain as illuminated by a set of conserved network-level connections identified in several vertebrate taxa. Aromatase-expressing neurons are neurochemically heterogeneous but the brain regions in which they are found are highly-conserved across the vertebrate lineage. During development, aromatase neurons have a prominent role in sexual differentiation of the brain and resultant sex differences in behavior and human brain diseases. Drawing on literature primarily from birds and rodents, we delineate brain regions that express aromatase and that are strongly interconnected, and suggest that, in many species, aromatase expression essentially defines the Social Behavior Network. Moreover, in several cases the inputs to and outputs from this core Social Behavior Network also express aromatase. Recent advances in molecular and genetic tools for neuroscience now enable in-depth and taxonomically diverse studies of the function of aromatase at the neural circuit level.
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Affiliation(s)
- Jeremy A Spool
- Center for Neuroendocrine Studies, Neuroscience and Behavior Graduate Program, University of Massachusetts, Amherst, MA 01003, United States
| | - Joseph F Bergan
- Center for Neuroendocrine Studies, Neuroscience and Behavior Graduate Program, University of Massachusetts, Amherst, MA 01003, United States
| | - Luke Remage-Healey
- Center for Neuroendocrine Studies, Neuroscience and Behavior Graduate Program, University of Massachusetts, Amherst, MA 01003, United States.
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4
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Ceccarelli I, Bioletti L, Peparini S, Solomita E, Ricci C, Casini I, Miceli E, Aloisi AM. Estrogens and phytoestrogens in body functions. Neurosci Biobehav Rev 2021; 132:648-663. [PMID: 34890602 DOI: 10.1016/j.neubiorev.2021.12.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/03/2021] [Accepted: 12/04/2021] [Indexed: 12/23/2022]
Abstract
Estrogens are the hormones of reproduction in women as well as of many other important functions in the male and female body. They undergo significant changes in the different phases of life, e.g. during puberty, pregnancy or at menopause/andropause. Phytoestrogens are natural non-steroidal phenolic plant compounds that can mimic the activity of estrogens and their beneficial effects in women and in men. This narrative review summarizes the literature on the physiological role of estrogens and the several potential health benefits of phytoestrogens, with particular attention given to the possible role of phytoestrogens in aging.
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Affiliation(s)
- Ilaria Ceccarelli
- Department Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Lucia Bioletti
- Department Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Sofia Peparini
- Department Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Erminia Solomita
- Department Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Comasia Ricci
- Department Life Sciences, University of Siena, Siena, Italy
| | - Ilenia Casini
- Department Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Elisangela Miceli
- Department Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Anna Maria Aloisi
- Department Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy.
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5
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Brann DW, Lu Y, Wang J, Zhang Q, Thakkar R, Sareddy GR, Pratap UP, Tekmal RR, Vadlamudi RK. Brain-derived estrogen and neural function. Neurosci Biobehav Rev 2021; 132:793-817. [PMID: 34823913 PMCID: PMC8816863 DOI: 10.1016/j.neubiorev.2021.11.014] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/26/2021] [Accepted: 11/12/2021] [Indexed: 01/02/2023]
Abstract
Although classically known as an endocrine signal produced by the ovary, 17β-estradiol (E2) is also a neurosteroid produced in neurons and astrocytes in the brain of many different species. In this review, we provide a comprehensive overview of the localization, regulation, sex differences, and physiological/pathological roles of brain-derived E2 (BDE2). Much of what we know regarding the functional roles of BDE2 has come from studies using specific inhibitors of the E2 synthesis enzyme, aromatase, as well as the recent development of conditional forebrain neuron-specific and astrocyte-specific aromatase knockout mouse models. The evidence from these studies support a critical role for neuron-derived E2 (NDE2) in the regulation of synaptic plasticity, memory, socio-sexual behavior, sexual differentiation, reproduction, injury-induced reactive gliosis, and neuroprotection. Furthermore, we review evidence that astrocyte-derived E2 (ADE2) is induced following brain injury/ischemia, and plays a key role in reactive gliosis, neuroprotection, and cognitive preservation. Finally, we conclude by discussing the key controversies and challenges in this area, as well as potential future directions for the field.
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Affiliation(s)
- Darrell W Brann
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA.
| | - Yujiao Lu
- Department of Neurosurgery, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Jing Wang
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Quanguang Zhang
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Roshni Thakkar
- Department of Neurology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA
| | - Gangadhara R Sareddy
- Department of Obstetrics and Gynecology, University of Texas Health, San Antoio TX, 78229, USA
| | - Uday P Pratap
- Department of Obstetrics and Gynecology, University of Texas Health, San Antoio TX, 78229, USA
| | - Rajeshwar R Tekmal
- Department of Obstetrics and Gynecology, University of Texas Health, San Antoio TX, 78229, USA
| | - Ratna K Vadlamudi
- Department of Obstetrics and Gynecology, University of Texas Health, San Antoio TX, 78229, USA; Audie L. Murphy Division, South Texas Veterans Health Care System, San Antonio, TX, 78229, USA.
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6
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Soutar CN, Grenier P, Patel A, Kabitsis PP, Olmstead MC, Bailey CDC, Dringenberg HC. Brain-Generated 17β-Estradiol Modulates Long-Term Synaptic Plasticity in the Primary Auditory Cortex of Adult Male Rats. Cereb Cortex 2021; 32:2140-2155. [PMID: 34628498 DOI: 10.1093/cercor/bhab345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Neuron-derived 17β-estradiol (E2) alters synaptic transmission and plasticity in brain regions with endocrine and non-endocrine functions. Investigations into a modulatory role of E2 in synaptic activity and plasticity have mainly focused on the rodent hippocampal formation. In songbirds, E2 is synthesized by auditory forebrain neurons and promotes auditory signal processing and memory for salient acoustic stimuli; however, the modulatory effects of E2 on memory-related synaptic plasticity mechanisms have not been directly examined in the auditory forebrain. We investigated the effects of bidirectional E2 manipulations on synaptic transmission and long-term potentiation (LTP) in the rat primary auditory cortex (A1). Immunohistochemistry revealed widespread neuronal expression of the E2 biosynthetic enzyme aromatase in multiple regions of the rat sensory and association neocortex, including A1. In A1, E2 application reduced the threshold for in vivo LTP induction at layer IV synapses, whereas pharmacological suppression of E2 production by aromatase inhibition abolished LTP induction at layer II/III synapses. In acute A1 slices, glutamate and γ-aminobutyric acid (GABA) receptor-mediated currents were sensitive to E2 manipulations in a layer-specific manner. These findings demonstrate that locally synthesized E2 modulates synaptic transmission and plasticity in A1 and suggest potential mechanisms by which E2 contributes to auditory signal processing and memory.
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Affiliation(s)
- Chloe N Soutar
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Patrick Grenier
- Department of Psychology, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Ashutosh Patel
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Pauline P Kabitsis
- Department of Psychology, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Mary C Olmstead
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario K7L 3N6, Canada.,Department of Psychology, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Craig D C Bailey
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Hans C Dringenberg
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario K7L 3N6, Canada.,Department of Psychology, Queen's University, Kingston, Ontario K7L 3N6, Canada
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7
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Sex neurosteroids: Hormones made by the brain for the brain. Neurosci Lett 2021; 753:135849. [PMID: 33775739 DOI: 10.1016/j.neulet.2021.135849] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/09/2021] [Accepted: 03/22/2021] [Indexed: 11/21/2022]
Abstract
In general, hippocampal neurons are capable of synthesizing sex steroids de novo from cholesterol, since the brain is equipped with all the enzymes required for the synthesis of estradiol and testosterone, the end products of sex steroidogenesis. Regarding estradiol, its synthesis in hippocampal neurons is homeostatically controlled by Ca2+ transients and is regulated by GnRH. Locally synthesized estradiol and testosterone maintain synaptic transmission and synaptic connectivity. Remarkably, the neurosteroid estradiol is effective in females, but not in males, and vice versa dihydrotestosterone (DHT) is effective in males, but not in females. Experimentally induced inhibition of estradiol synthesis in females and DHT synthesis in males resp. results in synapse loss, impaired LTP, and downregulation of synaptic proteins. GnRH-induced increase in estradiol synthesis appears to provide a link between the hypothalamus and the hippocampus, which may underlie estrous cyclicity of spine density in the female hippocampus. Hippocampal neurons are sex-dependently differentiated with respect to the responsiveness of hippocampal neurons to sex neurosteroids.
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8
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Bello-Alvarez C, Camacho-Arroyo I. Impact of sex in the prevalence and progression of glioblastomas: the role of gonadal steroid hormones. Biol Sex Differ 2021; 12:28. [PMID: 33752729 PMCID: PMC7986260 DOI: 10.1186/s13293-021-00372-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 03/04/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND As in other types of cancers, sex is an essential factor in the origin and progression of glioblastomas. Research in the field of endocrinology and cancer suggests that gonadal steroid hormones play an important role in the progression and prevalence of glioblastomas. In the present review, we aim to discuss the actions and mechanism triggered by gonadal steroid hormones in glioblastomas. MAIN BODY Glioblastoma is the most common malignant primary brain tumor. According to the epidemiological data, glioblastomas are more frequent in men than in women in a 1.6/1 proportion both in children and adults. This evidence, and the knowledge about sex influence over the prevalence of countless diseases, suggest that male gonadal steroid hormones, such as testosterone, promote glioblastomas growth. In contrast, a protective role of female gonadal steroid hormones (estradiol and progesterone) against glioblastomas has been questioned. Several pieces of evidence demonstrate a variety of effects induced by female and male gonadal steroid hormones in glioblastomas. Several studies indicate that pregnancy, a physiological state with the highest progesterone and estradiol levels, accelerates the progression of low-grade astrocytomas to glioblastomas and increases the symptoms associated with these tumors. In vitro studies have demonstrated that progesterone has a dual role in glioblastoma cells: physiological concentrations promote cell proliferation, migration, and invasion while very high doses (out physiological range) reduce cell proliferation and increases cell death. CONCLUSION Gonadal steroid hormones can stimulate the progression of glioblastomas through the increase in proliferation, migration, and invasion. However, the effects mentioned above depend on the concentrations of these hormones and the receptor involved in hormone actions. Estradiol and progesterone can exert promoter or protective effects while the role of testosterone has been always associated to glioblastomas progression.
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Affiliation(s)
- Claudia Bello-Alvarez
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), 04510, Ciudad de México, México
| | - Ignacio Camacho-Arroyo
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), 04510, Ciudad de México, México.
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9
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Neuron-Derived Estrogen Is Critical for Astrocyte Activation and Neuroprotection of the Ischemic Brain. J Neurosci 2020; 40:7355-7374. [PMID: 32817249 PMCID: PMC7534920 DOI: 10.1523/jneurosci.0115-20.2020] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 07/09/2020] [Accepted: 07/15/2020] [Indexed: 02/08/2023] Open
Abstract
17β-Estradiol (E2) is produced from androgens via the action of the enzyme aromatase. E2 is known to be made in neurons in the brain, but the functions of neuron-derived E2 in the ischemic brain are unclear. Here, we used a forebrain neuron-specific aromatase KO (FBN-ARO-KO) mouse model to deplete neuron-derived E2 in the forebrain and determine its roles after global cerebral ischemia. We demonstrated that ovariectomized female FBN-ARO-KO mice exhibited significantly attenuated astrocyte activation, astrocytic aromatization, and decreased hippocampal E2 levels compared with FLOX mice. Furthermore, FBN-ARO-KO mice had exacerbated neuronal damage and worse cognitive dysfunction after global cerebral ischemia. Similar results were observed in intact male mice. RNA-seq analysis revealed alterations in pathways and genes associated with astrocyte activation, neuroinflammation, and oxidative stress in FBN-ARO-KO mice. The compromised astrocyte activation in FBN-ARO-KO mice was associated with robust downregulation of the astrocyte-derived neurotrophic factors, BDNF and IGF-1, as well as the astrocytic glutamate transporter, GLT-1. Νeuronal FGF2, which acts in a paracrine manner to suppress astrocyte activation, was increased in FBN-ARO-KO neurons. Interestingly, blocking FGF2 signaling by central injection of FGFR3-neutralizing antibody was able to reverse the diminishment in neuroprotective astrocyte reactivity, and attenuate neuronal damage in FBN-ARO-KO mice. Moreover, in vivo E2 replacement suppressed FGF2 signaling and rescued the compromised reactive astrogliosis and cognitive deficits. Collectively, our data provide novel genetic evidence for a beneficial role of neuron-derived E2 in astrocyte activation, neuroprotection, and cognitive preservation following ischemic injury to the brain. SIGNIFICANCE STATEMENT Following cerebral ischemia, astrocytes become highly reactive and can exert neuroprotection through the release of neurotrophic factors and clearance of neurotoxic glutamate. The current study advances our understanding of this process by demonstrating that neuron-derived 17β-estradiol (E2) is neuroprotective and critical for induction of reactive astrocytes and their ability to produce astrocyte-derived neurotrophic factors, BDNF and IGF-1, and the glutamate transporter, GLT-1 after ischemic brain damage. These beneficial effects of neuron-derived E2 appear to be due, at least in part, to suppression of neuronal FGF2 signaling, which is a known suppressor of astrocyte activation. These findings suggest that neuron-derived E2 is neuroprotective after ischemic brain injury via a mechanism that involves suppression of neuronal FGF2 signaling, thereby facilitating astrocyte activation.
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10
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Camacho-Arroyo I, Piña-Medina AG, Bello-Alvarez C, Zamora-Sánchez CJ. Sex hormones and proteins involved in brain plasticity. VITAMINS AND HORMONES 2020; 114:145-165. [PMID: 32723542 DOI: 10.1016/bs.vh.2020.04.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
It is well known that peripheral sex steroid hormones cross the blood-brain barrier and control a broad spectrum of reproductive behaviors. However, their role in other essential brain functions was investigated since the 1980s, when the accumulation of pregnenolone and dehydroepiandrosterone in the brain of mammalian species was determined. Since then, numerous studies have demonstrated the participation of sex hormones in brain plasticity processes. Sex hormones through both genomic and non-genomic mechanisms of action are capable of inducing gene transcription or activating signaling cascades that result in the promotion of different physiological and pathological events of brain plasticity, such as remodeling or formation of dendritic spines, neurogenesis, synaptogenesis or myelination. In this chapter, we will present the effects of sex hormones and proteins involved in brain plasticity.
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Affiliation(s)
- Ignacio Camacho-Arroyo
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico.
| | - Ana Gabriela Piña-Medina
- Facultad de Química, Departamento de Biología, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, México
| | - Claudia Bello-Alvarez
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico
| | - Carmen J Zamora-Sánchez
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico
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11
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Brandt N, Fester L, Rune GM. Neural sex steroids and hippocampal synaptic plasticity. VITAMINS AND HORMONES 2020; 114:125-143. [PMID: 32723541 DOI: 10.1016/bs.vh.2020.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
It was a widely held belief that sex steroids, namely testosterone and 17β-estradiol (E2) of gonadal origin, control synaptic plasticity in the hippocampus. A new paradigm emerged when it was shown that these sex steroids are synthesized in the hippocampus. The inhibition of sex steroids in the hippocampus impairs synaptic plasticity sex-dependently in this region of the brain. In gonadectomized animals and in hippocampal cultures, inhibition of estradiol synthesis in female animals and in cultures from female animals, and inhibition of dihydrotestosterone synthesis in male animals and in cultures of male animals, cause synapse loss and impair LTP in the hippocampus, but not vice versa. Since the hippocampal cultures originated from perinatal animals, and due to the similarity of in vivo and in vitro findings, it appears that hippocampal neurons are differentiated in a sex-specific manner during the perinatal period when sexual imprinting takes place.
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Affiliation(s)
- N Brandt
- Center of Experimental Medicine, Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - L Fester
- Center of Experimental Medicine, Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - G M Rune
- Center of Experimental Medicine, Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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12
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Sellers KJ, Denley MCS, Saito A, Foster EM, Salgarella I, Delogu A, Kamiya A, Srivastava DP. Brain-synthesized oestrogens regulate cortical migration in a sexually divergent manner. Eur J Neurosci 2020; 52:2646-2663. [PMID: 32314480 DOI: 10.1111/ejn.14755] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 04/03/2020] [Accepted: 04/16/2020] [Indexed: 01/11/2023]
Abstract
Oestrogens play an important role in brain development where they have been implicated in controlling various cellular processes. Several lines of evidence have been presented showing that oestrogens can be synthesized locally within the brain. Studies have demonstrated that aromatase, the enzyme responsible for the conversion of androgens to oestrogens, is expressed during early development in both male and female cortices. Furthermore, 17β-oestradiol has been measured in foetal brain tissue from multiple species. 17β-oestradiol regulates neural progenitor proliferation as well as the development of early neuronal morphology. However, what role locally derived oestrogens play in regulating cortical migration and, moreover, whether these effects are the same in males and females are unknown. Here, we investigated the impact of knockdown expression of Cyp19a1, which encodes aromatase, between embryonic day (E) 14.5 and postnatal day 0 (P0) had on neural migration within the cortex. Aromatase was expressed in the developing cortex of both sexes, but at significantly higher levels in male than female mice. Under basal conditions, no obvious differences in cortical migration between male and female mice were observed. However, knockdown of Cyp19a1 resulted in an increase in cells within the cortical plate, and a concurrent decrease in the subventricular zone/ventricular zone in P0 male mice. Interestingly, the opposite effect was observed in females, who displayed a significant reduction in cells migrating to the cortical plate. Together, these findings indicate that brain-derived oestrogens regulate radial migration through distinct mechanisms in males and females.
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Affiliation(s)
- Katherine J Sellers
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
| | - Matthew C S Denley
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
| | - Atsushi Saito
- The Department of Psychiatry and Behavioral Sciences, John Hopkins University School of Medicine, Baltimore, MD, USA
| | - Evangeline M Foster
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Irene Salgarella
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Alessio Delogu
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Atsushi Kamiya
- The Department of Psychiatry and Behavioral Sciences, John Hopkins University School of Medicine, Baltimore, MD, USA
| | - Deepak P Srivastava
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
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13
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Ramírez-Barrantes R, Carvajal-Zamorano K, Rodriguez B, Cordova C, Lozano C, Simon F, Díaz P, Muñoz P, Marchant I, Latorre R, Castillo K, Olivero P. TRPV1-Estradiol Stereospecific Relationship Underlies Cell Survival in Oxidative Cell Death. Front Physiol 2020; 11:444. [PMID: 32528302 PMCID: PMC7265966 DOI: 10.3389/fphys.2020.00444] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Accepted: 04/09/2020] [Indexed: 12/31/2022] Open
Abstract
17β-estradiol is a neuronal survival factor against oxidative stress that triggers its protective effect even in the absence of classical estrogen receptors. The polymodal transient receptor potential vanilloid subtype 1 (TRPV1) channel has been proposed as a steroid receptor implied in tissue protection against oxidative damage. We show here that TRPV1 is sufficient condition for 17β-estradiol to enhance metabolic performance in injured cells. Specifically, in TRPV1 expressing cells, the application of 17β-estradiol within the first 3 h avoided H2O2-dependent mitochondrial depolarization and the activation of caspase 3/7 protecting against the irreversible damage triggered by H2O2. Furthermore, 17β-estradiol potentiates TRPV1 single channel activity associated with an increased open probability. This effect was not observed after the application of 17α-estradiol. We explored the TRPV1-Estrogen relationship also in primary culture of hippocampal-derived neurons and observed that 17β-estradiol cell protection against H2O2-induced damage was independent of estrogen receptors pathway activation, membrane started and stereospecific. These results support the role of TRPV1 as a 17β-estradiol-activated ionotropic membrane receptor coupling with mitochondrial function and cell survival.
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Affiliation(s)
- Ricardo Ramírez-Barrantes
- Laboratorio de Estructura y Función Celular, Escuela de Medicina, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile.,Escuela de Tecnología Médica, Universidad Andrés Bello, Viña del Mar, Chile
| | - Karina Carvajal-Zamorano
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Belen Rodriguez
- Laboratorio de Estructura y Función Celular, Escuela de Medicina, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile
| | - Claudio Cordova
- Laboratorio de Estructura y Función Celular, Escuela de Medicina, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile
| | - Carlo Lozano
- Laboratorio de Estructura y Función Celular, Escuela de Medicina, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile.,Centro Interoperativo en Ciencias Odontológicas y Médicas, Universidad de Valparaíso, Valparaíso, Chile
| | - Felipe Simon
- Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Chile, Santiago, Chile
| | - Paula Díaz
- Laboratorio de Estructura y Función Celular, Escuela de Medicina, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile
| | - Pablo Muñoz
- Centro de Neurología Traslacional, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile
| | - Ivanny Marchant
- Centro Interoperativo en Ciencias Odontológicas y Médicas, Universidad de Valparaíso, Valparaíso, Chile
| | - Ramón Latorre
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Karen Castillo
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Pablo Olivero
- Laboratorio de Estructura y Función Celular, Escuela de Medicina, Facultad de Medicina, Universidad de Valparaíso, Valparaíso, Chile.,Centro Interoperativo en Ciencias Odontológicas y Médicas, Universidad de Valparaíso, Valparaíso, Chile
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14
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Haumann I, Sturm MA, Anstötz M, Rune GM. GPER1 Signaling Initiates Migration of Female V-SVZ-Derived Cells. iScience 2020; 23:101077. [PMID: 32361597 PMCID: PMC7200306 DOI: 10.1016/j.isci.2020.101077] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 12/01/2019] [Accepted: 04/14/2020] [Indexed: 12/30/2022] Open
Abstract
In the rodent ventricular-subventricular zone (V-SVZ) neurons are generated throughout life. They migrate along the rostral migratory stream (RMS) into the olfactory bulb before their final differentiation into interneurons and integration into local circuits. Estrogen receptors (ERs) are steroid hormone receptors with important functions in neurogenesis and synaptic plasticity. In this study, we show that the ER GPER1 is expressed in subsets of cells within the V-SVZ of female animals and provide evidence for a potential local estrogen source from aromatase-positive astrocytes surrounding the RMS. Blocking of GPER1 in Matrigel cultures of female animals significantly impairs migration of V-SVZ-derived cells. This outgrowth is accompanied by regulation of phosphorylation of the actin-binding protein cofilin by GPER1 signaling including an involvement of the p21-Ras pathway. Our results point to a prominent role of GPER1 in the initiation of neuronal migration from the V-SVZ to the olfactory bulb. GPER1 is expressed within all cell types of the stem cell lineage in the V-SVZ Blocking of GPER1 leads to a decrease in migration of V-SVZ-derived neuroblasts GPER1 signaling in V-SVZ Matrigel cultures involves Ras-induced p21 Blocking of GPER1 signaling leads to an increase in the ratio of p-cofilin/cofilin
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Affiliation(s)
- Iris Haumann
- Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany.
| | - Muriel Anne Sturm
- Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Max Anstötz
- Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Gabriele M Rune
- Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany.
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15
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Duncan KA. Estrogen Formation and Inactivation Following TBI: What we Know and Where we Could go. Front Endocrinol (Lausanne) 2020; 11:345. [PMID: 32547495 PMCID: PMC7272601 DOI: 10.3389/fendo.2020.00345] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 05/04/2020] [Indexed: 01/27/2023] Open
Abstract
Traumatic brain injury (TBI) is responsible for various neuronal and cognitive deficits as well as psychosocial dysfunction. Characterized by damage inducing neuroinflammation, this response can cause an acute secondary injury that leads to widespread neurodegeneration and loss of neurological function. Estrogens decrease injury induced neuroinflammation and increase cell survival and neuroprotection and thus are a potential target for use following TBI. While much is known about the role of estrogens as a neuroprotective agent following TBI, less is known regarding their formation and inactivation following damage to the brain. Specifically, very little is known surrounding the majority of enzymes responsible for the production of estrogens. These estrogen metabolizing enzymes (EME) include aromatase, steroid sulfatase (STS), estrogen sulfotransferase (EST/SULT1E1), and some forms of 17β-hydroxysteroid dehydrogenase (HSD17B) and are involved in both the initial conversion and interconversion of estrogens from precursors. This article will review and offer new prospective and ideas on the expression of EMEs following TBI.
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16
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Duncan KA, Saldanha CJ. Central aromatization: A dramatic and responsive defense against threat and trauma to the vertebrate brain. Front Neuroendocrinol 2020; 56:100816. [PMID: 31786088 PMCID: PMC9366903 DOI: 10.1016/j.yfrne.2019.100816] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 11/15/2019] [Accepted: 11/19/2019] [Indexed: 01/09/2023]
Abstract
Aromatase is the requisite and limiting enzyme in the production of estrogens from androgens. Estrogens synthesized centrally have more recently emerged as potent neuroprotectants in the vertebrate brain. Studies in rodents and songbirds have identified key mechanisms that underlie both; the injury-dependent induction of central aromatization, and the protective effects of centrally synthesized estrogens. Injury-induced aromatase expression in astrocytes occurs following a broad range of traumatic brain damage including excitotoxic, penetrating, and concussive injury. Responses to neural insult such as edema and inflammation involve signaling pathways the components of which are excellent candidates as inducers of this astrocytic response. Finally, estradiol from astrocytes exerts a paracrine neuroprotective influence via the potent inhibition of inflammatory pathways. Taken together, these data suggest a novel role for neural aromatization as a protective mechanism against the threat of inflammation and suggests that central estrogen provision is a wide-ranging neuroprotectant in the vertebrate brain.
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Affiliation(s)
- Kelli A Duncan
- Department of Biology, Vassar College, Poughkeepsie, NY 12604, United States.
| | - Colin J Saldanha
- Department of Biology and Center for Behavioral Neuroscience, American University, Washington, DC 20016, United States.
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17
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Possible Existence of the Hypothalamic-Pituitary-Hippocampal (HPH) Axis: A Reciprocal Relationship Between Hippocampal Specific Neuroestradiol Synthesis and Neuroblastosis in Ageing Brains with Special Reference to Menopause and Neurocognitive Disorders. Neurochem Res 2019; 44:1781-1795. [PMID: 31254250 DOI: 10.1007/s11064-019-02833-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/13/2019] [Accepted: 06/19/2019] [Indexed: 12/18/2022]
Abstract
The hippocampus-derived neuroestradiol plays a major role in neuroplasticity, independent of circulating estradiol that originates from gonads. The response of hypothalamus-pituitary regions towards the synthesis of neuroestradiol in the hippocampus is an emerging scientific concept in cognitive neuroscience. Hippocampal plasticity has been proposed to be regulated via neuroblasts, a major cellular determinant of functional neurogenesis in the adult brain. Defects in differentiation, integration and survival of neuroblasts in the hippocampus appear to be an underlying cause of neurocognitive disorders. Gonadotropin receptors and steroidogenic enzymes have been found to be expressed in neuroblasts in the hippocampus of the brain. However, the reciprocal relationship between hippocampal-specific neuroestradiol synthesis along neuroblastosis and response of pituitary based feedback regulation towards regulation of estradiol level in the hippocampus have not completely been ascertained. Therefore, this conceptual article revisits (1) the cellular basis of neuroestradiol synthesis (2) a potential relationship between neuroestradiol synthesis and neuroblastosis in the hippocampus (3) the possible involvement of aberrant neuroestradiol production with mitochondrial dysfunctions and dyslipidemia in menopause and adult-onset neurodegenerative disorders and (4) provides a hypothesis for the possible existence of the hypothalamic-pituitary-hippocampal (HPH) axis in the adult brain. Eventually, understanding the regulation of hippocampal neurogenesis by abnormal levels of neuroestradiol concentration in association with the feedback regulation of HPH axis might provide additional cues to establish a neuroregenerative therapeutic management for mood swings, depression and cognitive decline in menopause and neurocognitive disorders.
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18
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Gley K, Murani E, Haack F, Trakooljul N, Zebunke M, Puppe B, Wimmers K, Ponsuksili S. Haplotypes of coping behavior associated QTL regions reveal distinct transcript profiles in amygdala and hippocampus. Behav Brain Res 2019; 372:112038. [PMID: 31202863 DOI: 10.1016/j.bbr.2019.112038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 06/06/2019] [Accepted: 06/12/2019] [Indexed: 12/15/2022]
Abstract
Stress response and coping behavior in pigs are largely shaped by hypothalamic-pituitary-adrenal axis and sympatho-adrenomedullary system action. However, the dynamic interaction between amygdala and hippocampus crucially modulates the behavioral response towards significant emotional events. While this functional relationship is well documented, the molecular underpinnings still remain insufficiently understood. Our study used transcriptome profiling of porcine amygdala and hippocampus to identify molecular pathways that are differentially activated depending on the haplotype of a significantly coping behavior-associated region on pig chromosome 12 (SSC12). The pigs were classified into two groups based on the haplotype information of this QTL-region discovered in our previous genome-wide association study. Ten each of high- (HR) and low- (LR) reactive pigs (n = 20) were selected for differential gene expression analysis and weighted gene co-expression analysis with subsequent pathway analysis. Differentially expressed genes identified in the amygdala include SELL, CXCR7 and NTS, while TRAF3, PTGS2 and CFI were detected in the hippocampus indicating a role of neuroinflammation and immunological processes. Pathway analysis revealed IL-8 signaling, NF-κB signaling, glutamate and GABA metabolism, glucocorticoid receptor signaling and chemokine signaling in the amygdala and ephrin receptor signaling, as well as NF-κB signaling in the hippocampus. We discovered candidate genes in regions detected by genome-wide association study including ARRB2, ADRBK2, THRB, NEK7 and ACVR2B, which relate to dopaminergic and other monoaminergic neurotransmitter systems, neuroimmunomodulation, neuroinflammation and GABA-ergic neurotransmission. These findings provide insights into the molecular underpinning of divergent coping behavior and associated haplotypes in limbic forebrain system in pig.
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Affiliation(s)
- Kevin Gley
- Leibniz Institute of Farm Animal Biology (FBN), Institute for Genome Biology, Wilhelm-Stahl-Allee 2, D-18196 Dummerstorf, Germany
| | - Eduard Murani
- Leibniz Institute of Farm Animal Biology (FBN), Institute for Genome Biology, Wilhelm-Stahl-Allee 2, D-18196 Dummerstorf, Germany
| | - Fiete Haack
- Leibniz Institute of Farm Animal Biology (FBN), Institute for Genome Biology, Wilhelm-Stahl-Allee 2, D-18196 Dummerstorf, Germany
| | - Nares Trakooljul
- Leibniz Institute of Farm Animal Biology (FBN), Institute for Genome Biology, Wilhelm-Stahl-Allee 2, D-18196 Dummerstorf, Germany
| | - Manuela Zebunke
- Leibniz Institute of Farm Animal Biology (FBN), Institute of Genetics and Biometry, Wilhelm-Stahl-Allee 2, D-18196 Dummerstorf, Germany; Leibniz Institute of Farm Animal Biology (FBN), Institute for Behavioral Physiology, Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Birger Puppe
- Leibniz Institute of Farm Animal Biology (FBN), Institute for Behavioral Physiology, Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Klaus Wimmers
- Leibniz Institute of Farm Animal Biology (FBN), Institute for Genome Biology, Wilhelm-Stahl-Allee 2, D-18196 Dummerstorf, Germany
| | - Siriluck Ponsuksili
- Leibniz Institute of Farm Animal Biology (FBN), Institute for Genome Biology, Wilhelm-Stahl-Allee 2, D-18196 Dummerstorf, Germany.
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19
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Crimins JL, Puri R, Calakos KC, Yuk F, Janssen WGM, Hara Y, Rapp PR, Morrison JH. Synaptic distributions of pS214-tau in rhesus monkey prefrontal cortex are associated with spine density, but not with cognitive decline. J Comp Neurol 2019; 527:856-873. [PMID: 30408169 PMCID: PMC6333519 DOI: 10.1002/cne.24576] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/18/2018] [Accepted: 10/21/2018] [Indexed: 12/31/2022]
Abstract
Female rhesus monkeys and women are subject to age- and menopause-related deficits in working memory, an executive function mediated by the dorsolateral prefrontal cortex (dlPFC). Long-term cyclic administration of 17β-estradiol improves working memory, and restores highly plastic axospinous synapses within layer III dlPFC of aged ovariectomized monkeys. In this study, we tested the hypothesis that synaptic distributions of tau protein phosphorylated at serine 214 (pS214-tau) are altered with age or estradiol treatment, and couple to working memory performance. First, ovariectormized young and aged monkeys received vehicle or estradiol treatment, and were tested on the delayed response (DR) test of working memory. Serial section electron microscopic immunocytochemistry was then performed to quantitatively assess the subcellular synaptic distributions of pS214-tau. Overall, the majority of synapses contained pS214-tau immunogold particles, which were predominantly localized to the cytoplasm of axon terminals. pS214-tau was also abundant within synaptic and cytoplasmic domains of dendritic spines. The density of pS214-tau immunogold within the active zone, cytoplasmic, and plasmalemmal domains of axon terminals, and subjacent to the postsynaptic density within the subsynaptic domains of dendritic spines, were each reduced with age. None of the variables examined were directly linked to cognitive status, but a high density of pS214-tau immunogold particles within presynaptic cytoplasmic and plasmalemmal domains, and within postsynaptic subsynaptic and plasmalemmal domains, accompanied high synapse density. Together, these data support a possible physiological, rather than pathological, role for pS214-tau in the modulation of synaptic morphology in monkey dlPFC.
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Affiliation(s)
- Johanna L. Crimins
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories Icahn School of Medicine at Mount Sinai, New York, NY 10029
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Rishi Puri
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories Icahn School of Medicine at Mount Sinai, New York, NY 10029
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Katina C. Calakos
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories Icahn School of Medicine at Mount Sinai, New York, NY 10029
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Frank Yuk
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories Icahn School of Medicine at Mount Sinai, New York, NY 10029
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - William G. M. Janssen
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories Icahn School of Medicine at Mount Sinai, New York, NY 10029
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Yuko Hara
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories Icahn School of Medicine at Mount Sinai, New York, NY 10029
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Peter R. Rapp
- National Institute on Aging, Laboratory of Behavioral Neuroscience, Baltimore, MD 21224
| | - John H. Morrison
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories Icahn School of Medicine at Mount Sinai, New York, NY 10029
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
- Department of Geriatrics and Palliative Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
- California National Primate Research Center, Davis, CA 95616
- Department of Neurology, School of Medicine, University of California, Davis, CA 95616
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20
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Neuron-Derived Estrogen Regulates Synaptic Plasticity and Memory. J Neurosci 2019; 39:2792-2809. [PMID: 30728170 PMCID: PMC6462452 DOI: 10.1523/jneurosci.1970-18.2019] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 12/28/2018] [Accepted: 01/18/2019] [Indexed: 01/27/2023] Open
Abstract
17β-estradiol (E2) is produced from androgens via the action of the enzyme aromatase. E2 is known to be made in neurons in the brain, but its precise functions in the brain are unclear. Here, we used a forebrain-neuron-specific aromatase knock-out (FBN-ARO-KO) mouse model to deplete neuron-derived E2 in the forebrain of mice and thereby elucidate its functions. FBN-ARO-KO mice showed a 70–80% decrease in aromatase and forebrain E2 levels compared with FLOX controls. Male and female FBN-ARO-KO mice exhibited significant deficits in forebrain spine and synaptic density, as well as hippocampal-dependent spatial reference memory, recognition memory, and contextual fear memory, but had normal locomotor function and anxiety levels. Reinstating forebrain E2 levels via exogenous in vivo E2 administration was able to rescue both the molecular and behavioral defects in FBN-ARO-KO mice. Furthermore, in vitro studies using FBN-ARO-KO hippocampal slices revealed that, whereas induction of long-term potentiation (LTP) was normal, the amplitude was significantly decreased. Intriguingly, the LTP defect could be fully rescued by acute E2 treatment in vitro. Mechanistic studies revealed that FBN-ARO-KO mice had compromised rapid kinase (AKT, ERK) and CREB-BDNF signaling in the hippocampus and cerebral cortex. In addition, acute E2 rescue of LTP in hippocampal FBN-ARO-KO slices could be blocked by administration of a MEK/ERK inhibitor, further suggesting a key role for rapid ERK signaling in neuronal E2 effects. In conclusion, the findings provide evidence of a critical role for neuron-derived E2 in regulating synaptic plasticity and cognitive function in the male and female brain. SIGNIFICANCE STATEMENT The steroid hormone 17β-estradiol (E2) is well known to be produced in the ovaries in females. Intriguingly, forebrain neurons also express aromatase, the E2 biosynthetic enzyme, but the precise functions of neuron-derived E2 is unclear. Using a novel forebrain-neuron-specific aromatase knock-out mouse model to deplete neuron-derived E2, the current study provides direct genetic evidence of a critical role for neuron-derived E2 in the regulation of rapid AKT-ERK and CREB-BDNF signaling in the mouse forebrain and demonstrates that neuron-derived E2 is essential for normal expression of LTP, synaptic plasticity, and cognitive function in both the male and female brain. These findings suggest that neuron-derived E2 functions as a novel neuromodulator in the forebrain to control synaptic plasticity and cognitive function.
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21
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Brocca ME, Garcia-Segura LM. Non-reproductive Functions of Aromatase in the Central Nervous System Under Physiological and Pathological Conditions. Cell Mol Neurobiol 2018; 39:473-481. [PMID: 30084008 DOI: 10.1007/s10571-018-0607-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 07/25/2018] [Indexed: 02/07/2023]
Abstract
The modulation of brain function and behavior by steroid hormones was classically associated with their secretion by peripheral endocrine glands. The discovery that the brain expresses the enzyme aromatase, which produces estradiol from testosterone, expanded this traditional concept. One of the best-studied roles of brain estradiol synthesis is the control of reproductive behavior. In addition, there is increasing evidence that estradiol from neural origin is also involved in a variety of non-reproductive functions. These include the regulation of neurogenesis, neuronal development, synaptic transmission, and plasticity in brain regions not directly related with the control of reproduction. Central aromatase is also involved in the modulation of cognition, mood, and non-reproductive behaviors. Furthermore, under pathological conditions aromatase is upregulated in the central nervous system. This upregulation represents a neuroprotective and likely also a reparative response by increasing local estradiol levels in order to maintain the homeostasis of the neural tissue. In this paper, we review the non-reproductive functions of neural aromatase and neural-derived estradiol under physiological and pathological conditions. We also consider the existence of sex differences in the role of the enzyme in both contexts.
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Affiliation(s)
- Maria Elvira Brocca
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain.
| | - Luis Miguel Garcia-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- Centro de Investigación Biomédica en Red Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
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22
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Vahaba DM, Remage-Healey L. Neuroestrogens rapidly shape auditory circuits to support communication learning and perception: Evidence from songbirds. Horm Behav 2018; 104:77-87. [PMID: 29555375 PMCID: PMC7025793 DOI: 10.1016/j.yhbeh.2018.03.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/15/2018] [Accepted: 03/15/2018] [Indexed: 12/19/2022]
Abstract
Contribution to Special Issue on Fast effects of steroids. Steroid hormones, such as estrogens, were once thought to be exclusively synthesized in the ovaries and enact transcriptional changes over the course of hours to days. However, estrogens are also locally synthesized within neural circuits, wherein they rapidly (within minutes) modulate a range of behaviors, including spatial cognition and communication. Here, we review the role of brain-derived estrogens (neuroestrogens) as modulators within sensory circuits in songbirds. We first present songbirds as an attractive model to explore how neuroestrogens in auditory cortex modulate vocal communication processing and learning. Further, we examine how estrogens may enhance vocal learning and auditory memory consolidation in sensory cortex via mechanisms similar to those found in the hippocampus of rodents and birds. Finally, we propose future directions for investigation, including: 1) the extent of developmental and hemispheric shifts in aromatase and membrane estrogen receptor expression in auditory circuits; 2) how neuroestrogens may impact inhibitory interneurons to regulate audition and critical period plasticity; and, 3) dendritic spine plasticity as a candidate mechanism mediating estrogen-dependent effects on vocal learning. Together, this perspective of estrogens as neuromodulators in the vertebrate brain has opened new avenues in understanding sensory plasticity, including how hormones can act on communication circuits to influence behaviors in other vocal learning species, such as in language acquisition and speech processing in humans.
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Affiliation(s)
- Daniel M Vahaba
- Neuroscience and Behavior Program, Center for Neuroendocrine Studies, University of Massachusetts Amherst, Amherst, MA 01003, United States
| | - Luke Remage-Healey
- Neuroscience and Behavior Program, Center for Neuroendocrine Studies, University of Massachusetts Amherst, Amherst, MA 01003, United States.
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23
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Reelin and aromatase cooperate in ovarian follicle development. Sci Rep 2018; 8:8722. [PMID: 29880879 PMCID: PMC5992190 DOI: 10.1038/s41598-018-26928-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 03/12/2018] [Indexed: 11/16/2022] Open
Abstract
Reelin plays an important role in cerebral cortex development and synaptogenesis. In the hippocampus, the neurosteroid estrogen affects reelin expression. In this study we tested a potential crosstalk between estradiol and reelin, thus the possibility of a reelin-induced activation of the estradiol synthesizing enzyme aromatase. As a model system, we used ovaries, which express reelin and are a major source of estradiol. We found that in wild-type mice, reelin and aromatase are expressed in granulosa cells of growing follicles. The expression of reelin varies with the estrus cycle and is highest shortly before ovulation, when estradiol serum levels are at their maximum. In ovaries of reelin-deficient reeler mice, aromatase mRNA and protein are significantly reduced, as evidenced by real-time PCR, western blot analysis, and quantitative immunohistochemistry in granulosa cells of preovulatory follicles. In line with reduced estradiol synthesis, ovarian estrus cycle length is prolonged in reeler mice. Most importantly, treating cultured granulosa cells with recombinant reelin results in significant upregulation of aromatase mRNA and protein and increased secretion of estradiol into the supernatant. Our data provide evidence of a local increase of aromatase expression by reelin. Regarding reproduction, this crosstalk may contribute to follicular stability and counteract luteinization in ovaries.
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24
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Denley MCS, Gatford NJF, Sellers KJ, Srivastava DP. Estradiol and the Development of the Cerebral Cortex: An Unexpected Role? Front Neurosci 2018; 12:245. [PMID: 29887794 PMCID: PMC5981095 DOI: 10.3389/fnins.2018.00245] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Accepted: 03/28/2018] [Indexed: 12/16/2022] Open
Abstract
The cerebral cortex undergoes rapid folding in an "inside-outside" manner during embryonic development resulting in the establishment of six discrete cortical layers. This unique cytoarchitecture occurs via the coordinated processes of neurogenesis and cell migration. In addition, these processes are fine-tuned by a number of extracellular cues, which exert their effects by regulating intracellular signaling pathways. Interestingly, multiple brain regions have been shown to develop in a sexually dimorphic manner. In many cases, estrogens have been demonstrated to play an integral role in mediating these sexual dimorphisms in both males and females. Indeed, 17β-estradiol, the main biologically active estrogen, plays a critical organizational role during early brain development and has been shown to be pivotal in the sexually dimorphic development and regulation of the neural circuitry underlying sex-typical and socio-aggressive behaviors in males and females. However, whether and how estrogens, and 17β-estradiol in particular, regulate the development of the cerebral cortex is less well understood. In this review, we outline the evidence that estrogens are not only present but are engaged and regulate molecular machinery required for the fine-tuning of processes central to the cortex. We discuss how estrogens are thought to regulate the function of key molecular players and signaling pathways involved in corticogenesis, and where possible, highlight if these processes are sexually dimorphic. Collectively, we hope this review highlights the need to consider how estrogens may influence the development of brain regions directly involved in the sex-typical and socio-aggressive behaviors as well as development of sexually dimorphic regions such as the cerebral cortex.
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Affiliation(s)
- Matthew C. S. Denley
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom
| | - Nicholas J. F. Gatford
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom
| | - Katherine J. Sellers
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom
| | - Deepak P. Srivastava
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, United Kingdom
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25
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Akinola OB, Gabriel MO. Neuroanatomical and molecular correlates of cognitive and behavioural outcomes in hypogonadal males. Metab Brain Dis 2018; 33:491-505. [PMID: 29230619 DOI: 10.1007/s11011-017-0163-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 11/28/2017] [Indexed: 12/18/2022]
Abstract
Robust epidemiological, clinical and laboratory evidence supports emerging roles for the sex steroids in such domains as neurodevelopment, behaviour, learning and cognition. Regions of the mammalian brain that are involved in cognitive development and memory do not only express the classical nuclear androgen receptor, but also the non-genomic membrane receptor, which is a G protein-coupled receptor that mediates some rapid effects of the androgens on neurogenesis and synaptic plasticity. Under physiological conditions, hippocampal neurons do express the enzyme aromatase, and therefore actively aromatize testosterone to oestradiol. Although glial expression of the aromatase enzyme is minimal, increased expression following injury suggests a role for sex steroids in neuroprotection. It is therefore plausible to deduce that low levels of circulating androgens in males would perturb neuronal functions in relation to cognition and memory, as well as neural repair following injury. The present review is an overview of some roles of the sex steroids on cognitive function in males, and the neuroanatomical and molecular underpinnings of some behavioural and cognitive deficits characteristic of such genetic disorders noted for low androgen levels, including Klinefelter syndrome, Bardet-Biedl syndrome, Kallman syndrome and Prader-Willi syndrome. Recent literature in relation to some behavioural and cognitive changes secondary to surgical and pharmacological castration are also appraised.
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Affiliation(s)
- O B Akinola
- Division of Endocrinology, Department of Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, University of Ilorin, Ilorin, Nigeria.
| | - M O Gabriel
- Division of Endocrinology, Department of Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, University of Ilorin, Ilorin, Nigeria
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26
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Neural-derived estradiol regulates brain plasticity. J Chem Neuroanat 2018; 89:53-59. [DOI: 10.1016/j.jchemneu.2017.04.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 03/16/2017] [Accepted: 04/12/2017] [Indexed: 01/12/2023]
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27
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Ikeda MZ, Krentzel AA, Oliver TJ, Scarpa GB, Remage-Healey L. Clustered organization and region-specific identities of estrogen-producing neurons in the forebrain of Zebra Finches (Taeniopygia guttata). J Comp Neurol 2017; 525:3636-3652. [PMID: 28758205 PMCID: PMC6035364 DOI: 10.1002/cne.24292] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 07/18/2017] [Accepted: 07/20/2017] [Indexed: 01/03/2023]
Abstract
A fast, neuromodulatory role for estrogen signaling has been reported in many regions of the vertebrate brain. Regional differences in the cellular distribution of aromatase (estrogen synthase) in several species suggest that mechanisms for neuroestrogen signaling differ between and even within brain regions. A more comprehensive understanding of neuroestrogen signaling depends on characterizing the cellular identities of neurons that express aromatase. Calcium-binding proteins such as parvalbumin and calbindin are molecular markers for interneuron subtypes, and are co-expressed with aromatase in human temporal cortex. Songbirds like the zebra finch have become important models to understand the brain synthesis of steroids like estrogens and the implications for neurobiology and behavior. Here, we investigated the regional differences in cytoarchitecture and cellular identities of aromatase-expressing neurons in the auditory and sensorimotor forebrain of zebra finches. Aromatase was co-expressed with parvalbumin in the caudomedial nidopallium (NCM) and HVC shelf (proper name) but not in the caudolateral nidopallium (NCL) or hippocampus. By contrast, calbindin was not co-expressed with aromatase in any region investigated. Notably, aromatase-expressing neurons were found in dense somato-somatic clusters, suggesting a coordinated release of local neuroestrogens from clustered neurons. Aromatase clusters were also more abundant and tightly packed in the NCM of males as compared to females. Overall, this study provides new insights into neuroestrogen regulation at the network level, and extends previous findings from human cortex by identifying a subset of aromatase neurons as putative inhibitory interneurons.
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Affiliation(s)
- Maaya Z Ikeda
- Molecular and Cellular Biology Program, University of Massachusetts, Amherst, Massachusetts
- Department of Psychological and Brain Sciences, University of Massachusetts, Amherst, Massachusetts
| | - Amanda A Krentzel
- Neuroscience and Behavior Program, University of Massachusetts, Amherst, Massachusetts
- Department of Psychological and Brain Sciences, University of Massachusetts, Amherst, Massachusetts
| | - Tessa J Oliver
- Department of Psychological and Brain Sciences, University of Massachusetts, Amherst, Massachusetts
| | - Garrett B Scarpa
- Department of Psychological and Brain Sciences, University of Massachusetts, Amherst, Massachusetts
| | - Luke Remage-Healey
- Molecular and Cellular Biology Program, University of Massachusetts, Amherst, Massachusetts
- Neuroscience and Behavior Program, University of Massachusetts, Amherst, Massachusetts
- Department of Psychological and Brain Sciences, University of Massachusetts, Amherst, Massachusetts
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28
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Lagranha CJ, Silva TLA, Silva SCA, Braz GRF, da Silva AI, Fernandes MP, Sellitti DF. Protective effects of estrogen against cardiovascular disease mediated via oxidative stress in the brain. Life Sci 2017; 192:190-198. [PMID: 29191645 DOI: 10.1016/j.lfs.2017.11.043] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 11/07/2017] [Accepted: 11/26/2017] [Indexed: 01/27/2023]
Abstract
During their reproductive years women produce significant levels of estrogens, predominantly in the form of estradiol, that are thought to play an important role in cardioprotection. Mechanisms underlying this action include both estrogen-mediated changes in gene expression, and post-transcriptional activation of protein signaling cascades in the heart and in neural centers controlling cardiovascular function, in particular, in the brainstem. There, specific neurons, especially those of the bulbar region play an important role in the neuronal control of the cardiovascular system because they control the outflow of sympathetic activity and parasympathetic activity as well as the reception of chemical and mechanical signals. In the present review, we discuss how estrogens exert their cardioprotective effect in part by modulating the actions of internally generated products of cellular oxidation such as reactive oxygen species (ROS) in brain stem neurons. The significance of this review is in integrating the literature of oxidative damage in the brain with the literature of neuroprotection by estrogen in order to better understand both the benefits and limitations of using this hormone to prevent cardiovascular disease.
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Affiliation(s)
- Claudia J Lagranha
- Neuropsychiatry and Behavior Science Graduate Program, Federal University of Pernambuco, 50670-901, Brazil; Laboratory of Biochemistry and Exercise Biochemistry, Department of Physical Education and Sports Science, Federal University of Pernambuco-CAV, Vitória de Santo Antão 55608-680, Brazil.
| | - Tercya Lucidi Araujo Silva
- Neuropsychiatry and Behavior Science Graduate Program, Federal University of Pernambuco, 50670-901, Brazil; Laboratory of Biochemistry and Exercise Biochemistry, Department of Physical Education and Sports Science, Federal University of Pernambuco-CAV, Vitória de Santo Antão 55608-680, Brazil
| | - Severina Cassia A Silva
- Laboratory of Biochemistry and Exercise Biochemistry, Department of Physical Education and Sports Science, Federal University of Pernambuco-CAV, Vitória de Santo Antão 55608-680, Brazil
| | - Glaber Ruda F Braz
- Laboratory of Biochemistry and Exercise Biochemistry, Department of Physical Education and Sports Science, Federal University of Pernambuco-CAV, Vitória de Santo Antão 55608-680, Brazil
| | - Aline Isabel da Silva
- Neuropsychiatry and Behavior Science Graduate Program, Federal University of Pernambuco, 50670-901, Brazil; Laboratory of Biochemistry and Exercise Biochemistry, Department of Physical Education and Sports Science, Federal University of Pernambuco-CAV, Vitória de Santo Antão 55608-680, Brazil
| | - Mariana Pinheiro Fernandes
- Laboratory of Biochemistry and Exercise Biochemistry, Department of Physical Education and Sports Science, Federal University of Pernambuco-CAV, Vitória de Santo Antão 55608-680, Brazil
| | - Donald F Sellitti
- Department of Anatomy, Physiology, and Genetics, School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
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Kraynak M, Flowers MT, Shapiro RA, Kapoor A, Levine JE, Abbott DH. Extraovarian gonadotropin negative feedback revealed by aromatase inhibition in female marmoset monkeys. Am J Physiol Endocrinol Metab 2017; 313:E507-E514. [PMID: 28679622 PMCID: PMC5792143 DOI: 10.1152/ajpendo.00058.2017] [Citation(s) in RCA: 12] [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] [Received: 02/17/2017] [Revised: 06/09/2017] [Accepted: 06/27/2017] [Indexed: 12/23/2022]
Abstract
Whereas the ovary produces the majority of estradiol (E2) in mature female primates, extraovarian sources contribute to E2 synthesis and action, including the brain E2-regulating hypothalamic gonadotropin-releasing hormone. In ovary-intact female rodent models, aromatase inhibition (AI) induces a polycystic ovary syndrome-like hypergonadotropic hyperandrogenism due to absent E2-mediated negative feedback. To examine the role of extraovarian E2 on nonhuman primate gonadotropin regulation, the present study uses letrozole to elicit AI in adult female marmoset monkeys. Sixteen female marmosets (Callithrix jacchus; >2 yr) were randomly assigned to ovary-intact or ovariectomy (OVX) conditions and subsequently placed on a daily oral regimen of either ~200 µl vehicle alone (ovary-intact Control, n = 3; OVX, n = 3) or 1 mg ⋅ kg-1 ⋅ day-1 letrozole in vehicle (ovary-intact AI, n = 4; OVX + AI, n = 6). Blood samples were collected every 10 days, and plasma chorionic gonadotropin (CG) and steroid hormone levels were determined by validated radioimmunoassay and liquid chromatography/tandem mass spectrometry, respectively. Ovary-intact, AI-treated and OVX females exhibited elevated CG (P < 0.01, P = 0.004, respectively) compared with controls, and after 30 days, OVX + AI females exhibited a suprahypergonadotropic phenotype (P = 0.004) compared with ovary-intact + AI and OVX females. Androstenedione (P = 0.03) and testosterone (P = 0.05) were also elevated in ovary-intact, AI-treated females above all other groups. The current study thus confirms in a nonhuman primate that E2 depletion and diminished negative feedback in ovary-intact females engage hypergonadotropic hyperandrogenism. Additionally, we demonstrate that extraovarian estrogens, possibly neuroestrogens, contribute to female negative feedback regulation of gonadotropin release.
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Affiliation(s)
- Marissa Kraynak
- Endocrinology and Reproductive Physiology Program, University of Wisconsin-Madison, Madison, Wisconsin;
- Department of Obstetrics and Gynecology, University of Wisconsin-Madison, Madison, Wisconsin
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin
| | - Matthew T Flowers
- Department of Neuroscience, University of Wisconsin-Madison, Madison, Wisconsin; and
| | - Robert A Shapiro
- Department of Neuroscience, University of Wisconsin-Madison, Madison, Wisconsin; and
| | - Amita Kapoor
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin
| | - Jon E Levine
- Department of Neuroscience, University of Wisconsin-Madison, Madison, Wisconsin; and
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin
| | - David H Abbott
- Department of Obstetrics and Gynecology, University of Wisconsin-Madison, Madison, Wisconsin
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin
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30
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On the role of brain aromatase in females: why are estrogens produced locally when they are available systemically? J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2017; 204:31-49. [PMID: 29086012 DOI: 10.1007/s00359-017-1224-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 10/12/2017] [Accepted: 10/17/2017] [Indexed: 01/27/2023]
Abstract
The ovaries are often thought of as the main and only source of estrogens involved in the regulation of female behavior. However, aromatase, the key enzyme for estrogen synthesis, although it is more abundant in males, is expressed and active in the brain of females where it is regulated by similar mechanisms as in males. Early work had shown that estrogens produced in the ventromedial hypothalamus are involved in the regulation of female sexual behavior in musk shrews. However, the question of the role of central aromatase in general had not received much attention until recently. Here, I will review the emerging concept that central aromatization plays a role in the regulation of physiological and behavioral endpoints in females. The data support the notion that in females, brain aromatase is not simply a non-functional evolutionary vestige, and provide support for the importance of locally produced estrogens for brain function in females. These observations should also have an impact for clinical research.
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31
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Crimins JL, Wang ACJ, Yuk F, Puri R, Janssen WGM, Hara Y, Rapp PR, Morrison JH. Diverse Synaptic Distributions of G Protein-coupled Estrogen Receptor 1 in Monkey Prefrontal Cortex with Aging and Menopause. Cereb Cortex 2017; 27:2022-2033. [PMID: 26941383 PMCID: PMC5909633 DOI: 10.1093/cercor/bhw050] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Age- and menopause-related impairment in working memory mediated by the dorsolateral prefrontal cortex (dlPFC) occurs in humans and nonhuman primates. Long-term cyclic 17β-estradiol treatment rescues cognitive deficits in aged ovariectomized rhesus monkeys while restoring highly plastic synapses. Here we tested whether distributions of G protein-coupled estrogen receptor 1 (GPER1) within monkey layer III dlPFC synapses are sensitive to age and estradiol, and coupled to cognitive function. Ovariectomized young and aged monkeys administered vehicle or estradiol were first tested on a delayed response test of working memory. Then, quantitative serial section immunoelectron microscopy was used to determine the distributions of synaptic GPER1. GPER1-containing nonperforated axospinous synapse density was reduced with age, and partially restored with estrogen treatment. The majority of synapses expressed GPER1, which was predominately localized to presynaptic cytoplasm and mitochondria. GPER1 was also abundant at plasmalemmas, and within cytoplasmic and postsynaptic density (PSD) domains of dendritic spines. GPER1 levels did not differ with age or treatment, and none of the variables examined were tightly associated with cognitive function. However, greater representation of GPER1 subjacent to the PSD accompanied higher synapse density. These data suggest that GPER1 is positioned to support diverse functions key to synaptic plasticity in monkey dlPFC.
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Affiliation(s)
| | - Athena Ching-Jung Wang
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, CO 80045, USA
| | - Frank Yuk
- Fishberg Department of Neuroscience and Friedman Brain Institute
| | - Rishi Puri
- Fishberg Department of Neuroscience and Friedman Brain Institute
| | | | - Yuko Hara
- Fishberg Department of Neuroscience and Friedman Brain Institute
| | - Peter R Rapp
- National Institute on Aging, Laboratory of Behavioral Neuroscience, Baltimore, MD 21224, USA
| | - John H Morrison
- Fishberg Department of Neuroscience and Friedman Brain Institute
- Department of Geriatrics and Palliative Medicine
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- California National Primate Research Center, Davis, CA 95616, USA
- Department of Neurology, School of Medicine, University of California Davis, Davis 95616, USA
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32
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Barakat R, Oakley O, Kim H, Jin J, Ko CJ. Extra-gonadal sites of estrogen biosynthesis and function. BMB Rep 2017; 49:488-96. [PMID: 27530684 PMCID: PMC5227141 DOI: 10.5483/bmbrep.2016.49.9.141] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Indexed: 12/23/2022] Open
Abstract
Estrogens are the key hormones regulating the development and function of reproductive organs in all vertebrates. Recent evidence indicates that estrogens play important roles in the immune system, cancer development, and other critical biological processes related to human well-being. Obviously, the gonads (ovary and testis) are the primary sites of estrogen synthesis, but estrogens synthesized in extra- gonadal sites play an equally important role in controlling biological activities. Understanding non-gonadal sites of estrogen synthesis and function is crucial and will lead to therapeutic interventions targeting estrogen signaling in disease prevention and treatment. Developing a rationale targeting strategy remains challenging because knowledge of extra-gonadal biosynthesis of estrogens, and the mechanism by which estrogen activity is exerted, is very limited. In this review, we will summarize recent discoveries of extra-gonadal sites of estrogen biosynthesis and their local functions and discuss the significance of the most recent novel discovery of intestinal estrogen biosynthesis. [BMB Reports 2016; 49(9): 488-496]
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Affiliation(s)
- Radwa Barakat
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Illinois 61802, Unites States; Department of Toxicology, Faculty of Veterinary Medicine, Benha University, Benha 13518, Egypt
| | - Oliver Oakley
- Department of Biology, College of Arts and Sciences, Eastern Kentucky University, Kentucky 40475, United States
| | - Heehyen Kim
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Korea
| | - Jooyoung Jin
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Korea
| | - CheMyong Jay Ko
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Illinois 61802, Unites States
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Sex-Dependent Regulation of Aromatase-Mediated Synaptic Plasticity in the Basolateral Amygdala. J Neurosci 2016; 37:1532-1545. [PMID: 28028198 DOI: 10.1523/jneurosci.1532-16.2016] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 11/11/2016] [Accepted: 12/11/2016] [Indexed: 02/01/2023] Open
Abstract
The basolateral amygdala (BLA) integrates sensory input from cortical and subcortical regions, a function that requires marked synaptic plasticity. Here we provide evidence that cytochrome P450 aromatase (AROM), the enzyme converting testosterone to 17β-estradiol (E2), contributes to the regulation of this plasticity in a sex-specific manner. We show that AROM is expressed in the BLA, particularly in the basolateral nucleus (BL), in male and female rodents. Systemic administration of the AROM inhibitor letrozole reduced spine synapse density in the BL of adult female mice but not in the BL of male mice. Similarly, in organotypic corticoamygdalar slice cultures from immature rats, treatment with letrozole significantly reduced spine synapses in the BL only in cultures derived from females. In addition, letrozole sex-specifically altered synaptic properties in the BL: in acute slices from juvenile (prepubertal) female rats, wash-in of letrozole virtually abolished long-term potentiation (LTP), whereas it did not prevent the generation of LTP in the slices from males. Together, these data indicate that neuron-derived E2 modulates synaptic plasticity in rodent BLA sex-dependently. As protein expression levels of AROM, estrogen and androgen receptors did not differ between males and females and were not sex-specifically altered by letrozole, the findings suggest sex-specific mechanisms of E2 signaling.SIGNIFICANCE STATEMENT The basolateral amygdala (BLA) is a key structure of the fear circuit. This research reveals a sexually dimorphic regulation of synaptic plasticity in the BLA involving neuronal aromatase, which produces the neurosteroid 17β-estradiol (E2). As male and female neurons in rodent BLA responded differently to aromatase inhibition both in vivo and in vitro, our findings suggest that E2 signaling in BLA neurons is regulated sex-dependently, presumably via mechanisms that have been established during sexual determination. These findings could be relevant for the understanding of sex differences in mood disorders and of the side effects of cytochrome P450 aromatase inhibitors, which are frequently used for breast cancer therapy.
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Crider A, Pillai A. Estrogen Signaling as a Therapeutic Target in Neurodevelopmental Disorders. J Pharmacol Exp Ther 2016; 360:48-58. [PMID: 27789681 DOI: 10.1124/jpet.116.237412] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 10/18/2016] [Indexed: 12/19/2022] Open
Abstract
Estrogens, the primary female sex hormones, were originally characterized through their important role in sexual maturation and reproduction. However, recent studies have shown that estrogens play critical roles in a number of brain functions, including cognition, learning and memory, neurodevelopment, and adult neuroplasticity. A number of studies from both clinical as well as preclinical research suggest a protective role of estrogen in neurodevelopmental disorders including autism spectrum disorder (ASD) and schizophrenia. Alterations in the levels of estrogen receptors have been found in subjects with ASD or schizophrenia, and adjunctive estrogen therapy has been shown to be effective in enhancing the treatment of schizophrenia. This review summarizes the findings on the role of estrogen in the pathophysiology of neurodevelopmental disorders with a focus on ASD and schizophrenia. We also discuss the potential of estrogen as a therapeutic target in the above disorders.
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Affiliation(s)
- Amanda Crider
- Department of Psychiatry and Health Behavior, Medical College of Georgia, Augusta University, Augusta, Georgia
| | - Anilkumar Pillai
- Department of Psychiatry and Health Behavior, Medical College of Georgia, Augusta University, Augusta, Georgia
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35
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Pietranera L, Correa J, Brocca ME, Roig P, Lima A, Di Giorgio N, Garcia-Segura LM, De Nicola AF. Selective Oestrogen Receptor Agonists Rescued Hippocampus Parameters in Male Spontaneously Hypertensive Rats. J Neuroendocrinol 2016; 28. [PMID: 27517478 DOI: 10.1111/jne.12415] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 08/09/2016] [Accepted: 08/10/2016] [Indexed: 12/21/2022]
Abstract
Spontaneously hypertensive rats (SHR) show pronounced hippocampus alterations, including low brain-derived neurotrophic factor (BDNF) expression, reduced neurogenesis, astrogliosis and increased aromatase expression. These changes are reverted by treatment with 17β-oestradiol. To determine which oestradiol receptor (ER) type is involved in these neuroprotective effects, we used agonists of the ERα [propylpyrazole triol (PPT)] and the ERβ [diarylpropionitrite (DPN)] given over 2 weeks to 4-month-old male SHR. Wistar Kyoto normotensive rats served as controls. Using immunocytochemistry, we determined glial fibrillary protein (GFAP)+ astrocytes in the CA1, CA3 and hilus of the dentate gyrus of the hippocampus, aromatase immunostaining in the hilus, and doublecortin (DCX)+ neuronal progenitors in the inner granular zone of the dentate gyrus. Brain-derived neurotrophic factor mRNA was also measured in the hippocampus by the quantitative polymerase chain reaction. In SHR, PPT had no effect on blood pressure, decreased astrogliosis, slightly increased BDNF mRNA, had no effect on the number of DCX+ progenitors, and increased aromatase staining. Treatment with DPN decreased blood pressure, decreased astrogliosis, increased BDNF mRNA and DCX+ progenitors, and did not modify aromatase staining. We hypothesise that, although both receptor types may participate in the previously reported beneficial effects of 17β-oestradiol in SHR, receptor activation with DPN may preferentially facilitate BDNF mRNA expression and neurogenesis. The results of the present study may help in the design of ER-based neuroprotection for the encephalopathy of hypertension.
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Affiliation(s)
- L Pietranera
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
- Department of Human Biochemistry, Faculty of Medicine, University of Buenos Aires, Buenos Aires, Argentina
| | - J Correa
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
| | - M E Brocca
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
| | - P Roig
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
| | - A Lima
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
| | - N Di Giorgio
- Laboratory of Neuroendocrinology, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
| | - L M Garcia-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Cientificas, Madrid, Spain
| | - A F De Nicola
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina.
- Department of Human Biochemistry, Faculty of Medicine, University of Buenos Aires, Buenos Aires, Argentina.
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36
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Acaz-Fonseca E, Avila-Rodriguez M, Garcia-Segura LM, Barreto GE. Regulation of astroglia by gonadal steroid hormones under physiological and pathological conditions. Prog Neurobiol 2016; 144:5-26. [DOI: 10.1016/j.pneurobio.2016.06.002] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 06/05/2016] [Indexed: 01/07/2023]
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37
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Fester L, Brandt N, Windhorst S, Pröls F, Bläute C, Rune GM. Control of aromatase in hippocampal neurons. J Steroid Biochem Mol Biol 2016; 160:9-14. [PMID: 26472556 DOI: 10.1016/j.jsbmb.2015.10.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 10/01/2015] [Accepted: 10/08/2015] [Indexed: 10/22/2022]
Abstract
Our knowledge on estradiol-induced modulation of synaptic function in the hippocampus is widely based on results following the application of the steroid hormone to either cell cultures, or after the treatment of gonadectomized animals, thus ignoring local neuronal estrogen synthesis. We and others, however, have shown that hippocampus-derived estradiol also controls synaptic plasticity in the hippocampus. Estradiol synthesis in the hippocampus is regulated by several mechanisms, which are reviewed in this report. The regulation of the activity of aromatase, the final enzyme of estrogen biosynthesis, by Ca(2+) transients, is of particular interest. Aromatase becomes inactivated as soon as it is phosphorylated by Ca(2+)-dependent kinases upon calcium release from internal stores. Accordingly, thapsigargin dephosphorylates aromatase and stimulates estradiol synthesis by depletion of internal Ca(2+) stores. Vice versa, letrozole, an aromatase inhibitor, phosphorylates aromatase and reduces estradiol synthesis. Treatment of the cultures with 17β-estradiol results in phosphorylation of the enzyme and increased aromatase protein expression, which suggests that estradiol synthesis in hippocampal neurons is regulated in an autocrine manner.
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Affiliation(s)
- Lars Fester
- University Medical Center Hamburg Eppendorf, Institute of Neuroanatomy, Martinistr. 52, 20246 Hamburg, Germany
| | - Nicola Brandt
- University Medical Center Hamburg Eppendorf, Institute of Neuroanatomy, Martinistr. 52, 20246 Hamburg, Germany
| | - Sabine Windhorst
- Department of Biochemistry and Signal Transduction, Martinistr. 52, 20246 Hamburg, Germany
| | - Felicitas Pröls
- University Medical Center Hamburg Eppendorf, Institute of Neuroanatomy, Martinistr. 52, 20246 Hamburg, Germany
| | - Corinna Bläute
- University Medical Center Hamburg Eppendorf, Institute of Neuroanatomy, Martinistr. 52, 20246 Hamburg, Germany
| | - Gabriele M Rune
- University Medical Center Hamburg Eppendorf, Institute of Neuroanatomy, Martinistr. 52, 20246 Hamburg, Germany.
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do Rego JL, Vaudry H. Comparative aspects of neurosteroidogenesis: From fish to mammals. Gen Comp Endocrinol 2016; 227:120-9. [PMID: 26079790 DOI: 10.1016/j.ygcen.2015.05.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 05/27/2015] [Accepted: 05/28/2015] [Indexed: 11/24/2022]
Abstract
It is now clearly established that the central and peripheral nervous systems have the ability to synthesize de novo steroids referred to as neurosteroids. The major evidence for biosynthesis of neuroactive steroids by nervous tissues is based on the expression of enzymes implicated in the formation of steroids in neural cells. The aim of the present review is to summarize the current knowledge regarding the presence of steroidogenic enzymes in the brain of vertebrates and to highlight the very considerable contribution of Professor Kazuyoshi Tsutsui in this domain. The data indicate that expression of steroid-producing enzymes in the brain appeared early during vertebrate evolution and has been preserved from fish to mammals.
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Affiliation(s)
- Jean Luc do Rego
- Institute for Research and Innovation in Biomedicine (IRIB), Institut National de la Santé et de la Recherche Médicale (INSERM), University of Rouen, 76821 Mont-Saint-Aignan, France
| | - Hubert Vaudry
- Institute for Research and Innovation in Biomedicine (IRIB), Institut National de la Santé et de la Recherche Médicale (INSERM), University of Rouen, 76821 Mont-Saint-Aignan, France; Neurotrophic Factors and Neuronal Differentiation Team, Inserm U982, University of Rouen, 76821 Mont-Saint-Aignan, France.
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Vahaba DM, Remage-Healey L. Brain estrogen production and the encoding of recent experience. Curr Opin Behav Sci 2015; 6:148-153. [PMID: 27453921 DOI: 10.1016/j.cobeha.2015.11.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The vertebrate central nervous system integrates cognition and behavior, and it also acts as both a source and target for steroid hormones like estrogens. Recent exploration of brain estrogen production in the context of learning and memory has revealed several common themes. First, across vertebrates, the enzyme that synthesizes estrogens is expressed in brain regions that are characterized by elevated neural plasticity and is also integral to the acquisition, consolidation, and retrieval of recent experiences. Second, measurement and manipulation of estrogens reveal that the period following recent sensory experience is linked to estrogenic signaling in brain circuits underlying both spatial and vocal learning. Local brain estrogen production within cognitive circuits may therefore be important for the acquisition and/or consolidation of memories, and new directions testing these ideas will be discussed.
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Affiliation(s)
- Daniel M Vahaba
- Neuroscience & Behavior Program, Center for Neuroendocrine Studies, University of Massachusetts, Amherst, MA, USA 01003
| | - Luke Remage-Healey
- Neuroscience & Behavior Program, Center for Neuroendocrine Studies, University of Massachusetts, Amherst, MA, USA 01003
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40
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Cisternas CD, Tome K, Caeiro XE, Dadam FM, Garcia-Segura LM, Cambiasso MJ. Sex chromosome complement determines sex differences in aromatase expression and regulation in the stria terminalis and anterior amygdala of the developing mouse brain. Mol Cell Endocrinol 2015; 414:99-110. [PMID: 26231585 DOI: 10.1016/j.mce.2015.07.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/24/2015] [Accepted: 07/25/2015] [Indexed: 10/23/2022]
Abstract
Aromatase, which converts testosterone in estradiol, is involved in the generation of brain sex dimorphisms. Here we used the "four core genotypes" mouse model, in which the effect of gonadal sex and sex chromosome complement is dissociated, to determine if sex chromosomes influence the expression of brain aromatase. The brain of 16 days old XY mouse embryos showed higher aromatase expression in the stria terminalis and the anterior amygdaloid area than the brain of XX embryos, independent of gonadal sex. Furthermore, estradiol or dihydrotestosterone increased aromatase expression in cultures of anterior amygdala neurons derived from XX embryos, but not in those derived from XY embryos. This effect was also independent of gonadal sex. The expression of other steroidogenic molecules, estrogen receptor-α and androgen receptor was not influenced by sex chromosomes. In conclusion, sex chromosomes determine sex dimorphisms in aromatase expression and regulation in the developing mouse brain.
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Affiliation(s)
- Carla D Cisternas
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina; Departamento de Biología Bucal, Facultad de Odontología - Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Karina Tome
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Ximena E Caeiro
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Florencia M Dadam
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | | | - María J Cambiasso
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina; Departamento de Biología Bucal, Facultad de Odontología - Universidad Nacional de Córdoba, Córdoba, Argentina.
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Hara Y, Waters EM, McEwen BS, Morrison JH. Estrogen Effects on Cognitive and Synaptic Health Over the Lifecourse. Physiol Rev 2015; 95:785-807. [PMID: 26109339 DOI: 10.1152/physrev.00036.2014] [Citation(s) in RCA: 250] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Estrogen facilitates higher cognitive functions by exerting effects on brain regions such as the prefrontal cortex and hippocampus. Estrogen induces spinogenesis and synaptogenesis in these two brain regions and also initiates a complex set of signal transduction pathways via estrogen receptors (ERs). Along with the classical genomic effects mediated by activation of ER α and ER β, there are membrane-bound ER α, ER β, and G protein-coupled estrogen receptor 1 (GPER1) that can mediate rapid nongenomic effects. All key ERs present throughout the body are also present in synapses of the hippocampus and prefrontal cortex. This review summarizes estrogen actions in the brain from the standpoint of their effects on synapse structure and function, noting also the synergistic role of progesterone. We first begin with a review of ER subtypes in the brain and how their abundance and distributions are altered with aging and estrogen loss (e.g., ovariectomy or menopause) in the rodent, monkey, and human brain. As there is much evidence that estrogen loss induced by menopause can exacerbate the effects of aging on cognitive functions, we then review the clinical trials of hormone replacement therapies and their effectiveness on cognitive symptoms experienced by women. Finally, we summarize studies carried out in nonhuman primate models of age- and menopause-related cognitive decline that are highly relevant for developing effective interventions for menopausal women. Together, we highlight a new understanding of how estrogen affects higher cognitive functions and synaptic health that go well beyond its effects on reproduction.
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Affiliation(s)
- Yuko Hara
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories, Friedman Brain Institute, Department of Geriatrics and Palliative Medicine, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York; and Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, New York, New York
| | - Elizabeth M Waters
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories, Friedman Brain Institute, Department of Geriatrics and Palliative Medicine, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York; and Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, New York, New York
| | - Bruce S McEwen
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories, Friedman Brain Institute, Department of Geriatrics and Palliative Medicine, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York; and Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, New York, New York
| | - John H Morrison
- Fishberg Department of Neuroscience and Kastor Neurobiology of Aging Laboratories, Friedman Brain Institute, Department of Geriatrics and Palliative Medicine, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York; and Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, New York, New York
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Carrier N, Saland SK, Duclot F, He H, Mercer R, Kabbaj M. The Anxiolytic and Antidepressant-like Effects of Testosterone and Estrogen in Gonadectomized Male Rats. Biol Psychiatry 2015; 78:259-69. [PMID: 25683735 PMCID: PMC4501899 DOI: 10.1016/j.biopsych.2014.12.024] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 12/03/2014] [Accepted: 12/19/2014] [Indexed: 01/01/2023]
Abstract
BACKGROUND While the influence of testosterone levels on vulnerability to affective disorders is not straightforward, research suggests this hormone may confer some degree of resiliency in men. We recently demonstrated a role for the dentate gyrus in mediating testosterone's protective effects on depressive-like behavior in gonadectomized male rats. Here, testosterone may exert its effects through androgen receptor-mediated mechanisms or via local aromatization to estradiol. METHODS Gonadectomized male rats were implanted with a placebo, testosterone, or estradiol pellet, and subsequent protective anxiolytic- and antidepressant-like effects of testosterone and its aromatized metabolite, estradiol, were then investigated in the open field and sucrose preference tests, respectively. Moreover, their influence on gene expression in the hippocampus was analyzed by genome-wide complementary DNA microarray analysis. Finally, the contribution of testosterone's aromatization within the dentate gyrus was assessed by local infusion of the aromatase inhibitor fadrozole, whose efficacy was confirmed by liquid chromatography-tandem mass spectrometry. RESULTS Both hormones had antidepressant-like effects associated with a substantial overlap in transcriptional regulation, particularly in synaptic plasticity- and mitogen-activated protein kinase pathway-related genes. Further, chronic aromatase inhibition within the dentate gyrus blocked the protective effects of testosterone. CONCLUSIONS Both testosterone and estradiol exhibit anxiolytic- and antidepressant-like effects in gonadectomized male rats, while similarly regulating critical mediators of these behaviors, suggesting common underlying mechanisms. Accordingly, we demonstrated that testosterone's protective effects are mediated, in part, by its aromatization in the dentate gyrus. These findings thus provide further insight into a role for estradiol in mediating the protective anxiolytic- and antidepressant-like effects of testosterone.
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Affiliation(s)
| | | | | | | | | | - Mohamed Kabbaj
- Department of Biomedical Sciences, Program in Neurosciences.
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Pietranera L, Brocca ME, Roig P, Lima A, Garcia-Segura LM, De Nicola AF. Estrogens are neuroprotective factors for hypertensive encephalopathy. J Steroid Biochem Mol Biol 2015; 146:15-25. [PMID: 24736028 DOI: 10.1016/j.jsbmb.2014.04.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 04/04/2014] [Accepted: 04/07/2014] [Indexed: 10/25/2022]
Abstract
Estrogens are neuroprotective factors for brain diseases, including hypertensive encephalopathy. In particular, the hippocampus is highly damaged by high blood pressure, with several hippocampus functions being altered in humans and animal models of hypertension. Working with a genetic model of primary hypertension, the spontaneously hypertensive rat (SHR), we have shown that SHR present decreased dentate gyrus neurogenesis, astrogliosis, low expression of brain derived neurotrophic factor (BDNF), decreased number of neurons in the hilus of the dentate gyrus, increased basal levels of the estrogen-synthesizing enzyme aromatase, and atrophic dendritic arbor with low spine density in the CA1 region compared to normotensive Wistar Kyoto (WKY) ratsl. Changes also occur in the hypothalamus of SHR, with increased expression of the hypertensinogenic peptide arginine vasopressin (AVP) and its V1b receptor. Following chronic estradiol treatment, SHR show decreased blood pressure, enhanced hippocampus neurogenesis, decreased the reactive astrogliosis, increased BDNF mRNA and protein expression in the dentate gyrus, increased neuronal number in the hilus of the dentate gyrus, further increased the hyperexpression of aromatase and replaced spine number with remodeling of the dendritic arbor of the CA1 region. We have detected by qPCR the estradiol receptors ERα and ERβ in hippocampus from both SHR and WKY rats, suggesting direct effects of estradiol on brain cells. We hypothesize that a combination of exogenously given estrogens plus those locally synthesized by estradiol-stimulated aromatase may better alleviate the hippocampal and hypothalamic encephalopathy of SHR. This article is part of a Special Issue entitled "Sex steroids and brain disorders".
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Affiliation(s)
- Luciana Pietranera
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina; Department of Human Biochemistry, Faculty of Medicine, University of Buenos Aires, Paraguay 2155, 1425 Buenos Aires, Argentina
| | - Maria Elvira Brocca
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina
| | - Paulina Roig
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina
| | - Analia Lima
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina
| | - Luis Miguel Garcia-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Cientificas, Avenida Doctor Arce 37, E-28002 Madrid, Spain
| | - Alejandro F De Nicola
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina; Department of Human Biochemistry, Faculty of Medicine, University of Buenos Aires, Paraguay 2155, 1425 Buenos Aires, Argentina.
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Pareto D, Biegon A, Alexoff D, Carter P, Shea C, Muench L, Xu Y, Fowler JS, Kim SW, Logan J. In vivo imaging of brain aromatase in female baboons: [11C]vorozole kinetics and effect of the menstrual cycle. Mol Imaging 2014; 12. [PMID: 24447618 DOI: 10.2310/7290.2013.00068] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The aim of this work was to quantify the brain distribution of the enzyme aromatase in the female baboon with positron emission tomography and the tracer [11C]vorozole using three different quantification methods for estimating the total distribution volume (V(T)): a graphical method, compartment modeling, and a tissue to plasma ratio. The graphical model and the compartment modeling gave similar estimates to the data and similar values (correlation R = .988; p = .0001). [11C]Vorozole shows a rapid uptake by the brain followed by a relatively constant accumulation, suggesting the possibility of using the tissue to plasma ratio as an estimate of V(T). The highest uptake of [11C]vorozole in the baboon brain was measured in the amygdala, followed by the preoptic area and hypothalamus, basal ganglia, and cortical areas. Pretreatment studies with vorozole or letrozole showed a generalized decrease in brain accumulation and V(T). The results suggested that the physiologic changes in gonadal hormone levels accompanying the menstrual cycle had a significant effect on brain aromatase V(T).
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45
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Li R, Cui J, Shen Y. Brain sex matters: estrogen in cognition and Alzheimer's disease. Mol Cell Endocrinol 2014; 389:13-21. [PMID: 24418360 PMCID: PMC4040318 DOI: 10.1016/j.mce.2013.12.018] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 12/31/2013] [Accepted: 12/31/2013] [Indexed: 02/06/2023]
Abstract
Estrogens are the primary female sex hormones and play important roles in both reproductive and non-reproductive systems. Estrogens can be synthesized in non-reproductive tissues such as liver, heart, muscle, bone and the brain. During the past decade, increasing evidence suggests that brain estrogen can not only be synthesized by neurons, but also by astrocytes. Brain estrogen also works locally at the site of synthesis in paracrine and/or intracrine fashion to maintain important tissue-specific functions. Here, we will focus on the biology of brain estrogen and its impact on cognitive function and Alzheimer's disease. This comprehensive review provides new insights into brain estrogens by presenting a better understanding of the tissue-specific estrogen effects and their roles in healthy ageing and cognitive function.
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Affiliation(s)
- Rena Li
- Center for Hormone Advanced Science and Education (CHASE), Roskamp Institute, Sarasota, FL 34243, United States.
| | - Jie Cui
- Center for Hormone Advanced Science and Education (CHASE), Roskamp Institute, Sarasota, FL 34243, United States
| | - Yong Shen
- Center for Advanced Therapeutic Strategies for Brain Disorders (CATSBD), Roskamp Institute, Sarasota, FL 34243, United States
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46
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Zhang QG, Wang R, Tang H, Dong Y, Chan A, Sareddy GR, Vadlamudi RK, Brann DW. Brain-derived estrogen exerts anti-inflammatory and neuroprotective actions in the rat hippocampus. Mol Cell Endocrinol 2014; 389:84-91. [PMID: 24508637 PMCID: PMC4040313 DOI: 10.1016/j.mce.2013.12.019] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 12/30/2013] [Accepted: 12/31/2013] [Indexed: 12/26/2022]
Abstract
17β-estradiol (E2) has been implicated to play a critical role in neuroprotection, synaptic plasticity, and cognitive function. Classically, the role of gonadal-derived E2 in these events is well established, but the role of brain-derived E2 is less clear. To address this issue, we investigated the expression, localization, and modulation of aromatase and local E2 levels in the hippocampus following global cerebral ischemia (GCI) in adult ovariectomized rats. Immunohistochemistry (IHC) revealed that the hippocampal regions CA1, CA3 and dentate gyrus (DG) exhibited high levels of immunoreactive aromatase staining, with aromatase being co-localized primarily in neurons in non-ischemic animals. Following GCI, aromatase became highly expressed in GFAP-positive astrocytes in the hippocampal CA1 region at 2-3 days post GCI reperfusion. An ELISA for E2 and IHC for E2 confirmed the GCI-induced elevation of local E2 in the CA1 region and that the increase in local E2 occurred in astrocytes. Furthermore, central administration of aromatase antisense (AS) oligonucleotides, but not missense (MS) oligonucleotides, blocked the increase in aromatase and local E2 in astrocytes after GCI, and resulted in a significant increase in GCI-induced hippocampal CA1 region neuronal cell death and neuroinflammation. As a whole, these results suggest that brain-derived E2 exerts important neuroprotective and anti-inflammatory actions in the hippocampal CA1 region following GCI.
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Affiliation(s)
- Quan-Guang Zhang
- Institute of Molecular Medicine and Genetics, Medical College of Georgia at Georgia Regents University, Augusta, GA 30912, USA.
| | - Ruimin Wang
- Institute of Molecular Medicine and Genetics, Medical College of Georgia at Georgia Regents University, Augusta, GA 30912, USA; Neurobiology Institute of Medical Research Centre, Hebei United University, Tangshan, Hebei 063000, PR China
| | - Hui Tang
- Institute of Molecular Medicine and Genetics, Medical College of Georgia at Georgia Regents University, Augusta, GA 30912, USA; Neurobiology Institute of Medical Research Centre, Hebei United University, Tangshan, Hebei 063000, PR China
| | - Yan Dong
- Institute of Molecular Medicine and Genetics, Medical College of Georgia at Georgia Regents University, Augusta, GA 30912, USA
| | - Alice Chan
- Institute of Molecular Medicine and Genetics, Medical College of Georgia at Georgia Regents University, Augusta, GA 30912, USA
| | - Gangadhara Reddy Sareddy
- Department of Obstetrics and Gynecology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Ratna K Vadlamudi
- Department of Obstetrics and Gynecology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Darrell W Brann
- Institute of Molecular Medicine and Genetics, Medical College of Georgia at Georgia Regents University, Augusta, GA 30912, USA.
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Klein RC, Saini S, Risher ML, Acheson SK, Fleming RL, Sexton HG, Swartzwelder HS, Moore SD. Regional-specific effects of ovarian hormone loss on synaptic plasticity in adult human APOE targeted replacement mice. PLoS One 2014; 9:e94071. [PMID: 24732142 PMCID: PMC3986067 DOI: 10.1371/journal.pone.0094071] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 03/11/2014] [Indexed: 12/27/2022] Open
Abstract
The human apolipoprotein ε4 allele (APOE4) has been implicated as one of the strongest genetic risk factors associated with Alzheimer’s disease (AD) and in influencing normal cognitive functioning. Previous studies have demonstrated that mice expressing human apoE4 display deficits in behavioral and neurophysiological outcomes compared to those with apoE3. Ovarian hormones have also been shown to be important in modulating synaptic processes underlying cognitive function, yet little is known about how their effects are influenced by apoE. In the current study, female adult human APOE targeted replacement (TR) mice were utilized to examine the effects of human APOE genotype and long-term ovarian hormone loss on synaptic plasticity in limbic regions by measuring dendritic spine density and electrophysiological function. No significant genotype differences were observed on any outcomes within intact mice. However, there was a significant main effect of genotype on total spine density in apical dendrites in the hippocampus, with post-hoc t-tests revealing a significant reduction in spine density in apoE3 ovariectomized (OVX) mice compared to sham operated mice. There was also a significant main effect of OVX on the magnitude of LTP, with post-hoc t-tests revealing a decrease in apoE3 OVX mice relative to sham. In contrast, apoE4 OVX mice showed increased synaptic activity relative to sham. In the lateral amygdala, there was a significant increase in total spine density in apoE4 OVX mice relative to sham. This increase in spine density was consistent with a significant increase in spontaneous excitatory activity in apoE4 OVX mice. These findings suggest that ovarian hormones differentially modulate synaptic integrity in an apoE-dependent manner within brain regions that are susceptible to neurophysiological dysfunction associated with AD.
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Affiliation(s)
- Rebecca C. Klein
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
- MIRECC, Durham Veterans Affairs Medical Center, Durham, North Carolina, United States of America
- * E-mail:
| | - Shyla Saini
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
| | - M-Louise Risher
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Shawn K. Acheson
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
- Neurobiology Research Lab, Durham Veterans Affairs Medical Center, Durham, North Carolina, United States of America
| | - Rebekah L. Fleming
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
- Neurobiology Research Lab, Durham Veterans Affairs Medical Center, Durham, North Carolina, United States of America
| | - Hannah G. Sexton
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
- Neurobiology Research Lab, Durham Veterans Affairs Medical Center, Durham, North Carolina, United States of America
| | - H. Scott Swartzwelder
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
- Neurobiology Research Lab, Durham Veterans Affairs Medical Center, Durham, North Carolina, United States of America
| | - Scott D. Moore
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
- MIRECC, Durham Veterans Affairs Medical Center, Durham, North Carolina, United States of America
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48
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Coumailleau P, Kah O. Cyp19a1 (aromatase) expression in the Xenopus brain at different developmental stages. J Neuroendocrinol 2014; 26:226-36. [PMID: 24612124 PMCID: PMC4238815 DOI: 10.1111/jne.12142] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 02/17/2014] [Accepted: 02/22/2014] [Indexed: 12/24/2022]
Abstract
Cytochrome P450 aromatase (P450arom; aromatase) is a microsomal enzyme involved in the production of endogeneous sex steroids by converting testosterone into oestradiol. Aromatase is the product of the cyp19a1 gene and plays a crucial role in the sexual differentiation of the brain and in the regulation of reproductive functions. In the brain of mammals and birds, expression of cyp19a1 has been demonstrated in neuronal populations of the telencephalon and diencephalon. By contrast, a wealth of evidence established that, in teleost fishes, aromatase expression in the brain is restricted to radial glial cells. The present study investigated the precise neuroanatomical distribution of cyp19a1 mRNA during brain development in Xenopus laevis (late embryonic to juvenile stages). For this purpose, we used in situ hybridisation alone or combined with the detection of a proliferative (proliferating cell nuclear antigen), glial (brain lipid binding protein, Vimentin) or neuronal (acetylated tubulin; HuC/D; NeuroβTubulin) markers. We provide evidence that cyp19a1 expression in the brain is initiated from the very early larval stage and remains strongly detected until the juvenile and adult stages. At all stages analysed, we found the highest expression of cyp19a1 in the preoptic area and the hypothalamus compared to the rest of the brain. In these two brain regions, cyp19a1-positive cells were never detected in the ventricular layers. Indeed, no co-labelling could be observed with radial glial (brain lipid binding protein, Vimentin) or dividing progenitors (proliferating cell nuclear antigen) markers. By contrast, cyp19a1-positive cells perfectly matched with the distribution of post-mitotic neurones as shown by the use of specific markers (HuC/D, acetylated tubulin and NeuroβTubulin). These data suggest that, similar to that found in other tetrapods, aromatase in the brain of amphibians is found in post-mitotic neurones and not in radial glia as reported in teleosts.
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Affiliation(s)
- P Coumailleau
- Neuroendocrine Effects of Endocrine Disruptors, IRSET, INSERM U1085, SFR Biosit, Université de Rennes 1, Rennes, France
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Srivastava DP, Woolfrey KM, Penzes P. Insights into rapid modulation of neuroplasticity by brain estrogens. Pharmacol Rev 2013; 65:1318-50. [PMID: 24076546 PMCID: PMC3799233 DOI: 10.1124/pr.111.005272] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Converging evidence from cellular, electrophysiological, anatomic, and behavioral studies suggests that the remodeling of synapse structure and function is a critical component of cognition. This modulation of neuroplasticity can be achieved through the actions of numerous extracellular signals. Moreover, it is thought that it is the integration of different extracellular signals regulation of neuroplasticity that greatly influences cognitive function. One group of signals that exerts powerful effects on multiple neurologic processes is estrogens. Classically, estrogens have been described to exert their effects over a period of hours to days. However, there is now increasing evidence that estrogens can rapidly influence multiple behaviors, including those that require forebrain neural circuitry. Moreover, these effects are found in both sexes. Critically, it is now emerging that the modulation of cognition by rapid estrogenic signaling is achieved by activation of specific signaling cascades and regulation of synapse structure and function, cumulating in the rewiring of neural circuits. The importance of understanding the rapid effects of estrogens on forebrain function and circuitry is further emphasized as investigations continue to consider the potential of estrogenic-based therapies for neuropathologies. This review focuses on how estrogens can rapidly influence cognition and the emerging mechanisms that underlie these effects. We discuss the potential sources and the biosynthesis of estrogens within the brain and the consequences of rapid estrogenic-signaling on the remodeling of neural circuits. Furthermore, we argue that estrogens act via distinct signaling pathways to modulate synapse structure and function in a manner that may vary with cell type, developmental stage, and sex. Finally, we present a model in which the coordination of rapid estrogenic-signaling and activity-dependent stimuli can result in long-lasting changes in neural circuits, contributing to cognition, with potential relevance for the development of novel estrogenic-based therapies for neurodevelopmental or neurodegenerative disorders.
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Affiliation(s)
- Deepak P Srivastava
- Department of Neuroscience & Centre for the Cellular Basis of Behaviour, 125 Coldharbour Lane, The James Black Centre, Institute of Psychiatry, King's College London, London, SE5 9NU, UK.
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Miyajima M, Kusuhara H, Takahashi K, Takashima T, Hosoya T, Watanabe Y, Sugiyama Y. Investigation of the effect of active efflux at the blood–brain barrier on the distribution of nonsteroidal aromatase inhibitors in the central nervous system. J Pharm Sci 2013; 102:3309-19. [DOI: 10.1002/jps.23600] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 04/21/2013] [Accepted: 04/23/2013] [Indexed: 12/25/2022]
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