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Arjmand S, Bender D, Jakobsen S, Wegener G, Landau AM. Peering into the Brain's Estrogen Receptors: PET Tracers for Visualization of Nuclear and Extranuclear Estrogen Receptors in Brain Disorders. Biomolecules 2023; 13:1405. [PMID: 37759805 PMCID: PMC10526964 DOI: 10.3390/biom13091405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/12/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
Estrogen receptors (ERs) play a multitude of roles in brain function and are implicated in various brain disorders. The use of positron emission tomography (PET) tracers for the visualization of ERs' intricate landscape has shown promise in oncology but remains limited in the context of brain disorders. Despite recent progress in the identification and development of more selective ligands for various ERs subtypes, further optimization is necessary to enable the reliable and efficient imaging of these receptors. In this perspective, we briefly touch upon the significance of estrogen signaling in the brain and raise the setbacks associated with the development of PET tracers for identification of specific ERs subtypes in the brain. We then propose avenues for developing efficient PET tracers to non-invasively study the dynamics of ERs in the brain, as well as neuropsychiatric diseases associated with their malfunction in a longitudinal manner. This perspective puts several potential candidates on the table and highlights the unmet needs and areas requiring further research to unlock the full potential of PET tracers for ERs imaging, ultimately aiding in deepening our understanding of ERs and forging new avenues for potential therapeutic strategies.
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Affiliation(s)
- Shokouh Arjmand
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark;
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital, 8200 Aarhus, Denmark; (D.B.); (S.J.)
| | - Dirk Bender
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital, 8200 Aarhus, Denmark; (D.B.); (S.J.)
| | - Steen Jakobsen
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital, 8200 Aarhus, Denmark; (D.B.); (S.J.)
| | - Gregers Wegener
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark;
| | - Anne M. Landau
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark;
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital, 8200 Aarhus, Denmark; (D.B.); (S.J.)
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2
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Casto KV, Jordan T, Petersen N. Hormone-based models for comparing menstrual cycle and hormonal contraceptive effects on human resting-state functional connectivity. Front Neuroendocrinol 2022; 67:101036. [PMID: 36126748 PMCID: PMC9649880 DOI: 10.1016/j.yfrne.2022.101036] [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: 04/20/2022] [Revised: 09/07/2022] [Accepted: 09/12/2022] [Indexed: 11/19/2022]
Abstract
Oral contraceptives (OCs) are widely used yet understudied given their potential for public health consequences. Emerging investigations scaling from single-subject, dense-sampling neuroimaging studies to population-level metrics have linked OCs to altered brain structure and function. Modeling the hypogonadal, hypergonadal, or mixed state effects of OCs in terms of their impact on hormone action in the brain is a valuable approach to synthesizing results across neuroimaging studies and comparing OC effects to companion findings from research on menstrual cycle phase effects on brain anatomy and function. Resting-state functional connectivity studies provide a powerful tool to evaluate the role of OCs on the intrinsic network connectivity that underlies multiple behavioral domains. The preponderance (but not consensus) of the current literature indicates that (1) as the menstrual cycle proceeds from a low to high progesterone state, prefrontal connectivity increases and parietal connectivity decreases; (2) OCs tend to mimic this connectivity pattern; therefore (3) OCs may produce a hyperprogestogenic state in the brain, in spite of overall reductions in endogenous steroid hormone levels. Alternative models are also considered.
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Affiliation(s)
- Kathleen V Casto
- Social Sciences Division, New College of Florida, 5800 Bay Shore Road, Sarasota, FL 34243, USA
| | - Timothy Jordan
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, 760 Westwood Plaza, Los Angeles, CA 90095, USA
| | - Nicole Petersen
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, 760 Westwood Plaza, Los Angeles, CA 90095, USA.
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Romero-Morales L, García-Saucedo B, Martínez-Torres M, Cárdenas-Vázquez R, Álvarez-Rodríguez C, Carmona A, Luis J. PATERNAL AND INFANTICIDAL BEHAVIOR IN THE MONGOLIAN GERBIL (Meriones unguiculatus): AN APPROACH TO NEUROENDOCRINE REGULATION. Behav Brain Res 2021; 415:113520. [PMID: 34389425 DOI: 10.1016/j.bbr.2021.113520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 12/22/2022]
Abstract
This study aimed to provide evidence on estrogen and androgen pathways regulating the Mongolian gerbil's paternal and infanticidal behaviors (Meriones unguiculatus). We analyzed estrogen receptor alpha (ERα) and androgen receptor (AR) distribution in the medial preoptic area (mPOA), the bed nucleus of stria terminalis (BNST), as well as the anterior hypothalamic nucleus (AHN), the ventromedial hypothalamus nucleus (VMH), and the periaqueductal gray area (PAG) nuclei activated when males interact paternally or aggressively with the pups, respectively. Twenty aggressive males towards the pups and 10 paternal were selected through a screen paternal behavior test. Three groups of 10 males each were formed: paternal males (PAT), males with testosterone (T)-induced paternal behavior (T-PAT), and aggressive males (AGG). Male gerbils could interact with a pup for a few minutes, and their brains were removed and dissected for ERα and AR immunoreactivity (ir). The results showed that in T-PAT and PAT males, the number of ERα-ir and AR-ir cells in the mPOA/BNST was significantly higher than in AGG males. In AGG males, the number of ERα-ir and AR-ir cells in the AHN/VMH/PAG was significantly higher than PAT and T-PAT males. This difference in the presence of ERα and AR in nuclei activated in paternal interactions in the Mongolian gerbil supports the idea that these receptors participate in regulating paternal behavior. Also, these results suggest, for the first time, that they could be involved in the infanticidal behavior in this rodent.
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Affiliation(s)
- Luis Romero-Morales
- Laboratorio de Biología de la Reproducción, UMF, FES Iztacala, Universidad Nacional Autónoma de México, Av. de los Barrios No. 1, Tlalnepantla, Edo. de México, Mexico.
| | - Brenda García-Saucedo
- Laboratorio de Biología de la Reproducción, UMF, FES Iztacala, Universidad Nacional Autónoma de México, Av. de los Barrios No. 1, Tlalnepantla, Edo. de México, Mexico.
| | - Martín Martínez-Torres
- Laboratorio de Biología de la Reproducción, UMF, FES Iztacala, Universidad Nacional Autónoma de México, Av. de los Barrios No. 1, Tlalnepantla, Edo. de México, Mexico
| | - René Cárdenas-Vázquez
- Laboratorio de Biología Animal Experimental, Depto. de Biología Celular, Facultad de Ciencias, UNAM, Mexico.
| | - Carmen Álvarez-Rodríguez
- Laboratorio de Biología de la Reproducción, UMF, FES Iztacala, Universidad Nacional Autónoma de México, Av. de los Barrios No. 1, Tlalnepantla, Edo. de México, Mexico
| | | | - Juana Luis
- Laboratorio de Biología de la Reproducción, UMF, FES Iztacala, Universidad Nacional Autónoma de México, Av. de los Barrios No. 1, Tlalnepantla, Edo. de México, Mexico.
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4
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Herrera-Morales WV, Herrera-Solís A, Núñez-Jaramillo L. Sexual Behavior and Synaptic Plasticity. ARCHIVES OF SEXUAL BEHAVIOR 2019; 48:2617-2631. [PMID: 31270644 DOI: 10.1007/s10508-019-01483-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 05/30/2019] [Accepted: 06/01/2019] [Indexed: 06/09/2023]
Abstract
Although sex drive is present in many animal species, sexual behavior is not static and, like many other behaviors, can be modified by experience. This modification relies on synaptic plasticity, a sophisticated mechanism through which neurons change how they process a given stimulus, and the neurophysiological basis of learning. This review addresses the main plastic effects of steroid sex hormones in the central nervous system (CNS) and the effects of sexual experience on the CNS, including effects on neurogenesis, intracellular signaling, gene expression, and changes in dendritic spines, as well as behavioral changes.
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Affiliation(s)
- Wendy Verónica Herrera-Morales
- División de Ciencias de la Salud, Universidad de Quintana Roo, Av. Erick Paolo Martínez S/N esquina Av 4 de marzo. Colonia Magisterial, 77039, Chetumal, Quintana Roo, Mexico
| | - Andrea Herrera-Solís
- Laboratorio Efectos Terapéuticos de los Canabinoides, Subdirección de Investigación Biomédica, Hospital General Dr. Manuel Gea González, Ciudad de México, Mexico
| | - Luis Núñez-Jaramillo
- División de Ciencias de la Salud, Universidad de Quintana Roo, Av. Erick Paolo Martínez S/N esquina Av 4 de marzo. Colonia Magisterial, 77039, Chetumal, Quintana Roo, Mexico.
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Ravi M, Stevens JS, Michopoulos V. Neuroendocrine pathways underlying risk and resilience to PTSD in women. Front Neuroendocrinol 2019; 55:100790. [PMID: 31542288 PMCID: PMC6876844 DOI: 10.1016/j.yfrne.2019.100790] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 08/26/2019] [Accepted: 09/18/2019] [Indexed: 01/23/2023]
Abstract
Women are twice as likely than men to suffer from posttraumatic stress disorder (PTSD). While women have increased exposure to traumatic events of many types and have greater prevalence of comorbid psychiatric disorders compared to men, these differences do not account for the overall sex difference in the prevalence of PTSD. The current review summarizes significant findings that implicate the role of estradiol, progesterone, and allopregnanolone in female risk for PTSD symptoms and dysregulation of fear psychophysiology that is cardinal to PTSD. We also discuss how these steroid hormones influence the stress axis and neural substrates critical for the regulation of fear responses. Understanding the role of ovarian steroid hormones in risk and resilience for trauma-related adverse mental health outcomes across the lifespan in women has important translational, clinical, and intergenerational implications for mitigating the consequences of trauma exposure.
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Affiliation(s)
- Meghna Ravi
- Emory University Graduate Program in Neuroscience, Atlanta, GA, United States
| | - Jennifer S Stevens
- Emory University School of Medicine, Department of Psychiatry and Behavioral Sciences, Atlanta, GA, United States
| | - Vasiliki Michopoulos
- Emory University School of Medicine, Department of Psychiatry and Behavioral Sciences, Atlanta, GA, United States; Yerkes National Primate Research Center, Atlanta, GA, United States.
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Hull EM, Dominguez JM. Neuroendocrine Regulation of Male Sexual Behavior. Compr Physiol 2019; 9:1383-1410. [DOI: 10.1002/cphy.c180018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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8
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Babenko O, Kovalchuk I, Metz GAS. Stress-induced perinatal and transgenerational epigenetic programming of brain development and mental health. Neurosci Biobehav Rev 2014; 48:70-91. [PMID: 25464029 DOI: 10.1016/j.neubiorev.2014.11.013] [Citation(s) in RCA: 324] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 09/19/2014] [Accepted: 11/17/2014] [Indexed: 12/20/2022]
Abstract
Research efforts during the past decades have provided intriguing evidence suggesting that stressful experiences during pregnancy exert long-term consequences on the future mental wellbeing of both the mother and her baby. Recent human epidemiological and animal studies indicate that stressful experiences in utero or during early life may increase the risk of neurological and psychiatric disorders, arguably via altered epigenetic regulation. Epigenetic mechanisms, such as miRNA expression, DNA methylation, and histone modifications are prone to changes in response to stressful experiences and hostile environmental factors. Altered epigenetic regulation may potentially influence fetal endocrine programming and brain development across several generations. Only recently, however, more attention has been paid to possible transgenerational effects of stress. In this review we discuss the evidence of transgenerational epigenetic inheritance of stress exposure in human studies and animal models. We highlight the complex interplay between prenatal stress exposure, associated changes in miRNA expression and DNA methylation in placenta and brain and possible links to greater risks of schizophrenia, attention deficit hyperactivity disorder, autism, anxiety- or depression-related disorders later in life. Based on existing evidence, we propose that prenatal stress, through the generation of epigenetic alterations, becomes one of the most powerful influences on mental health in later life. The consideration of ancestral and prenatal stress effects on lifetime health trajectories is critical for improving strategies that support healthy development and successful aging.
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Affiliation(s)
- Olena Babenko
- Canadian Centre for Behavioural Neuroscience, Department of Neuroscience, University of Lethbridge, 4401 University Drive, Lethbridge, AB, Canada T1K 3M4; Department of Biological Sciences, University of Lethbridge, 4401 University Drive, Lethbridge, AB, Canada T1K 3M4
| | - Igor Kovalchuk
- Department of Biological Sciences, University of Lethbridge, 4401 University Drive, Lethbridge, AB, Canada T1K 3M4
| | - Gerlinde A S Metz
- Canadian Centre for Behavioural Neuroscience, Department of Neuroscience, University of Lethbridge, 4401 University Drive, Lethbridge, AB, Canada T1K 3M4
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Effects of SCH-23390 in combination with a low dose of 17β-estradiol on anxiety-like behavior in ovariectomized rats. BIOMED RESEARCH INTERNATIONAL 2014; 2014:847821. [PMID: 24707499 PMCID: PMC3953507 DOI: 10.1155/2014/847821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 12/29/2013] [Accepted: 01/19/2014] [Indexed: 01/07/2023]
Abstract
The aim of this study was to explore effects on anxiety-like behavior of D1 dopamine receptor agonist, SKF-38393, and of D1 dopamine receptor antagonist, SCH-23390, given alone or in combination with a low dose of 17β-estradiol (17β-E2) to ovariectomized (OVX) rats. Two weeks after surgery, OVX rats began 14 days of treatment with the vehicle, a low dose of 17β-E2 (5.0 μg/rat, s.c.), SKF-38393 (0.1 mg/kg, i.p.), SCH-23390 (0.1 mg/kg, i.p.), SKF-38393 plus 17β-E2, or SCH-23390 plus 17β-E2. The animals were tested in the black and white model (BWM) and the open field test (OFT). SCH-23390 (0.1 mg/kg, i.p.) alone or in a combination with a low dose of 17β-E2 (5.0 μg/rat, s.c.) resulted in anxiolytic-like effect in OVX rats in the BWM. Repeated treatment with SCH-23390 and 17β-E2 profoundly increased anxiolytic-like effect of single substances exerted per se. Coadministration of SCH-23390 with 17β-E2 increased frequency of rearing and grooming in OVX rats in OFT. SKF-38393 (0.1 mg/kg, i.p.) treatment failed to alter anxiety-like behavior in OVX rats in the BWM. The results of the present study suggest that 17β-E2 and SCH-23390 interact to exert anxiolytic-like action and that each of these drugs can potentiate effects of each other.
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Carter SN, Goldman BD, Goldman SL, Freeman DA. Social cues elicit sexual behavior in subordinate Damaraland mole-rats independent of gonadal status. Horm Behav 2014; 65:14-21. [PMID: 24246377 DOI: 10.1016/j.yhbeh.2013.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 11/04/2013] [Accepted: 11/05/2013] [Indexed: 11/18/2022]
Abstract
Damaraland mole-rats (Fukomys damarensis) are among a small number of eusocial mammals. Eusociality is a social system where only a few individuals within a colony engage in direct reproduction, while remaining subordinate members are non-breeders and support reproductive efforts of breeding individuals. Inbreeding avoidance precludes mating between subordinate siblings and between offspring and parents. Interestingly, non-breeders readily attempt to mate with unrelated opposite-sex individuals. This is unusual since the non-breeding females do not attain puberty while in their natal colony. Based on this finding, the present study investigated the role of the gonads in the regulation of mating behaviors in this species and identified the mechanism of inbreeding avoidance. Gonadal-intact and gonadectomized non-breeders from different colonies were removed from their colonies and tested for the expression of sexual behavior. Results indicated that gonadal status had only minor effects on the expression of sexual behavior in either males or females. In a second experiment, sexual behaviors were absent between opposite-sex siblings so long as they had frequent contact with each other; however, following 5 weeks of separation, sexual behavior between these siblings was robustly expressed. Thus, Damaraland mole-rats avoid establishing mating relationships with familiar individuals but will readily mate with unfamiliar individuals of the opposite sex, with genetic relatedness apparently playing little role. The initiation of sexual behavior in Damaraland mole-rats does not require the presence of the gonads, but does require that the members of the pair have not been in contact with one another for at least several weeks.
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Affiliation(s)
- Sara N Carter
- Department of Biological Sciences, University of Memphis, 3774 Walker Avenue, Life Sciences Building, Memphis, TN 38152, USA.
| | - Bruce D Goldman
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
| | - Sharry L Goldman
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
| | - David A Freeman
- Department of Biological Sciences, University of Memphis, 3774 Walker Avenue, Life Sciences Building, Memphis, TN 38152, USA.
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Fedotova J. Anxiolytic-like effect of quinpirole in combination with a low dose of 17β-estradiol in ovariectomized rats. ACTA ACUST UNITED AC 2013; 100:211-23. [DOI: 10.1556/aphysiol.100.2013.2.8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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12
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Weber KP, Alvaro CG, Baer GM, Reinert K, Cheng G, Clever S, Wightman B. Analysis of C. elegans NR2E nuclear receptors defines three conserved clades and ligand-independent functions. BMC Evol Biol 2012; 12:81. [PMID: 22690911 PMCID: PMC3517510 DOI: 10.1186/1471-2148-12-81] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Accepted: 05/31/2012] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The nuclear receptors (NRs) are an important class of transcription factors that are conserved across animal phyla. Canonical NRs consist of a DNA-binding domain (DBD) and ligand-binding domain (LBD). While most animals have 20-40 NRs, nematodes of the genus Caenorhabditis have experienced a spectacular proliferation and divergence of NR genes. The LBDs of evolutionarily-conserved Caenorhabditis NRs have diverged sharply from their Drosophila and vertebrate orthologs, while the DBDs have been strongly conserved. The NR2E family of NRs play critical roles in development, especially in the nervous system. In this study, we explore the phylogenetics and function of the NR2E family of Caenorhabditis elegans, using an in vivo assay to test LBD function. RESULTS Phylogenetic analysis reveals that the NR2E family of NRs consists of three broadly-conserved clades of orthologous NRs. In C. elegans, these clades are defined by nhr-67, fax-1 and nhr-239. The vertebrate orthologs of nhr-67 and fax-1 are Tlx and PNR, respectively. While the nhr-239 clade includes orthologs in insects (Hr83), an echinoderm, and a hemichordate, the gene appears to have been lost from vertebrate lineages. The C. elegans and C. briggsae nhr-239 genes have an apparently-truncated and highly-diverged LBD region. An additional C. elegans NR2E gene, nhr-111, appears to be a recently-evolved paralog of fax-1; it is present in C. elegans, but not C. briggsae or other animals with completely-sequenced genomes. Analysis of the relatively unstudied nhr-111 and nhr-239 genes demonstrates that they are both expressed--nhr-111 very broadly and nhr-239 in a small subset of neurons. Analysis of the FAX-1 LBD in an in vivo assay revealed that it is not required for at least some developmental functions. CONCLUSIONS Our analysis supports three conserved clades of NR2E receptors, only two of which are represented in vertebrates, indicating three ancestral NR2E genes in the urbilateria. The lack of a requirement for a FAX-1 LBD suggests that the relatively high level of sequence divergence for Caenorhabditis LBDs reflects relaxed selection on the primary sequence as opposed to divergent positive selection. This observation is consistent with a model in which divergence of some Caenorhabditis LBDs is allowed, at least in part, by the absence of a ligand requirement.
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Affiliation(s)
| | | | - G Michael Baer
- Biology Department, Muhlenberg College, Allentown, PA, 18104, USA
| | - Kristy Reinert
- Biology Department, Muhlenberg College, Allentown, PA, 18104, USA
| | - Genevieve Cheng
- Biology Department, Muhlenberg College, Allentown, PA, 18104, USA
| | - Sheila Clever
- Biology Department, Muhlenberg College, Allentown, PA, 18104, USA
| | - Bruce Wightman
- Biology Department, Muhlenberg College, Allentown, PA, 18104, USA
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Hernández-Fonseca K, Massieu L, García de la Cadena S, Guzmán C, Camacho-Arroyo I. Neuroprotective role of estradiol against neuronal death induced by glucose deprivation in cultured rat hippocampal neurons. Neuroendocrinology 2012; 96:41-50. [PMID: 22213775 DOI: 10.1159/000334229] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 10/08/2011] [Indexed: 12/22/2022]
Abstract
Studies have reported the protective effect of estradiol (E(2)) against neuronal death induced by several insults including oxygen deprivation, mitochondrial toxins and activation of glutamate receptors. Glucose deprivation (GD) is associated with ischemia and hypoglycemia, and to date there is no effective therapeutic agent able to prevent neuronal damage induced by these conditions. In this study, we have investigated the effects of 17β-E(2) and the selective agonists of the alpha (ERα) and beta (ERβ) estrogen receptors, propyl pyrazole triol (PPT) and diarylpropionitrile (DPN), respectively, on neuronal death induced by GD in cultured rat hippocampal neurons. We have also analyzed the expression of both ER isoforms after GD. Results show that GD for 2 and 4 h reduces cell survival by 42 and 55%, respectively. Treatment with 17β-E(2) (10 nM to 10 µM) induces a dose-dependent protective effect that is blocked by ICI 182,780, an ER antagonist, and by 1,3-bis(4-hydroxyphenyl)-4-methyl-5-[4-(-piperidinylethoxy)phenol]-1H'pyrazole dihydrochloride (MPP) and 4-[2-phenyl-5,7-bis(trifluoromethyl)pyrazolo[1,5-a]pyrimidin-3-yl]phenol (PHTPP), selective ERα and ERβ antagonists, respectively. The ERα and ERβ agonists PPT and DPN show a similar neuroprotective effect to that of 17β-E(2), but DPN is more efficient. In addition, hippocampal neurons under normal conditions show a higher expression of the ERβ isoform. When exposed to GD during 4 h, the expression of both ER isoforms is increased, while only that of the ERβ isoform significantly increases after 2 h of GD. Results demonstrate that E(2) prevents neuronal death induced by GD through its interaction with ER, although the ERβ isoform might have a predominant role. Results also suggest that GD differentially alters the expression of ERα and ERβ in hippocampal neurons.
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Bouchard P, Chabbert-Buffet N, Fauser BCJM. Selective progesterone receptor modulators in reproductive medicine: pharmacology, clinical efficacy and safety. Fertil Steril 2011; 96:1175-89. [PMID: 21944187 DOI: 10.1016/j.fertnstert.2011.08.021] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 08/08/2011] [Accepted: 08/12/2011] [Indexed: 11/19/2022]
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15
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Fedotova J, Ordyan N. Involvement of D1receptors in depression-like behavior of ovariectomized rats. ACTA ACUST UNITED AC 2011; 98:165-76. [DOI: 10.1556/aphysiol.98.2011.2.8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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16
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Sower SA, Baron MP. The interrelationship of estrogen receptor and GnRH in a Basal vertebrate, the sea lamprey. Front Endocrinol (Lausanne) 2011; 2:58. [PMID: 22654815 PMCID: PMC3356121 DOI: 10.3389/fendo.2011.00058] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Accepted: 10/04/2011] [Indexed: 11/20/2022] Open
Abstract
The hypothalamic-pituitary system is considered to be a vertebrate innovation and seminal event that emerged prior to or during the differentiation of the ancestral agnathans. Lampreys are the earliest evolved vertebrates for which there is a demonstrated neuroendocrine system. Lampreys have three hypothalamic gonadotropin-releasing hormones (GnRHs; lGnRH-I, -II, and -III) and two and possibly three pituitary GnRH receptors involved in mediating reproductive processes. Estradiol is considered to be a major reproductive steroid in both male and female lampreys. The purpose of this study was to investigate estrogen receptor (ER) expression in the lamprey brain in adult sea lampreys. Expression of ER mRNA was confirmed in the adult lamprey brain using RT-PCR. Using digoxigenin (DIG)-labeled probes, ER expression was shown to yield moderate, but distinct reaction products in specific neuronal nuclei of the lamprey brain, including the olfactory lobe, hypothalamus, habenular area, and hindbrain. Expression of ER in the hypothalamic area of the brain provides evidence of potential interaction between estradiol and GnRH(s), and is consistent with previous evidence showing estrogen feedback on GnRH in adult lamprey brain. Earlier studies have reported that there is a close distribution of glutamic acid decarboxylase (GAD; GABA-synthesizing enzyme) and lamprey GnRH in the preoptic region in adult lampreys. The establishment of a direct estradiol-kisspeptin-GABA-GnRH interaction in lamprey has yet to be determined and will require future functional and co-localization studies. The phylogenetic position of lampreys as a basal vertebrate allows lampreys to be a basis for understanding the molecular evolution of the neuroendocrine system that arose in the vertebrates.
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Affiliation(s)
- Stacia A. Sower
- Department of Molecular, Cellular and Biomedical Sciences, Center for Molecular and Comparative Endocrinology, University of New HampshireDurham, NH, USA
- *Correspondence: Stacia A. Sower, Department of Molecular, Cellular and Biomedical Sciences, Center for Molecular and Comparative Endocrinology, University of New Hampshire, 46 College Road, Durham, NH 03824-3544, USA. e-mail:
| | - Michael P. Baron
- Department of Molecular, Cellular and Biomedical Sciences, Center for Molecular and Comparative Endocrinology, University of New HampshireDurham, NH, USA
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Bradshaw FJ, Bradshaw D. Progesterone and reproduction in marsupials: a review. Gen Comp Endocrinol 2011; 170:18-40. [PMID: 20688062 DOI: 10.1016/j.ygcen.2010.07.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Revised: 07/25/2010] [Accepted: 07/28/2010] [Indexed: 01/26/2023]
Abstract
Progesterone (P4) profiles throughout pregnancy and the oestrous cycle are reviewed in a wide range of marsupial species, representing 12 Families, and focus on the corpus luteum (CL) and its functioning, compared with its eutherian counterpart. Physiologically, P4 subtends the same fundamental processes supporting gestation in marsupials as it does in eutherian mammals, from its role in stimulating the secretory endometrium, effecting nutritional transfer across the placenta and establishing lactogenesis. Before the formation of the CL, however, secretion of P4 is widespread throughout many Families and the dual roles of P4 in the induction of sexual behaviour and ovulation are exposed. In Dasyuridae, raised levels of P4 are linked with the induction of sexual receptivity and are also present around the time of mating in Burramyidae, Petauridae and Tarsipedidae, but their function is unknown. Only in Didelphidae has research established that the pheromonally-induced levels of pro-oestrous P4 trigger ovulation. This is principally the role of oestradiol in the eutherian and may be an important difference between the marsupial and the eutherian. The deposition of the shell coat around the early marsupial embryo is also a function of P4, but perhaps the most striking difference is seen in the time taken to form the CL. This is not always immediate and the maximum secretion of P4 from the granulosa cells may not occur until some 2 weeks after ovulation. The slower development of the CL in some species is linked with delays in the development of the embryo during its unattached phase and results in relatively long gestation periods. A common feature of these, in monovular species, is a short pulse of P4 from the newly-luteinised CL, which is all that is needed for the subsequent development of the embryo to term. Maternal recognition of pregnancy occurs soon after the formation of the blastocyst, with embryo-induced changes in ovarian production of P4 and the uterine endometrium. The embryo, similar to the eutherian, determines the length of the gestation period and initiates its own birth, but in direct contrast, the embryo of some marsupial species shortens the life-span of the CL. The evidence points to a different strategy; one of a reduction, rather than an expansion of the potential ovarian and placental support available during pregnancy. The marsupial mode of reproduction, where all species produce highly altricial young, receiving complex and extensive maternal care, has facilitated the adaptive radiation of this group and avoided the need for precociality.
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Affiliation(s)
- Felicity J Bradshaw
- School of Animal Biology M092, The University of Western Australia, Perth, Western Australia, Australia.
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Hernández-Díaz I, Giraldez T, Arnau MR, Smits VAJ, Jaisser F, Farman N, Alvarez de la Rosa D. The mineralocorticoid receptor is a constitutive nuclear factor in cardiomyocytes due to hyperactive nuclear localization signals. Endocrinology 2010; 151:3888-99. [PMID: 20484457 DOI: 10.1210/en.2010-0099] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The mineralocorticoid receptor (MR), a member of the nuclear receptor family, mediates the action of aldosterone in target epithelia, enhancing sodium reabsorption. In addition, MR may have other physiological functions in nonepithelial tissues. Altered expression or inappropriate activation of cardiac MR is directly linked to the development of cardiac fibrosis, and MR blockade is beneficial for the treatment of heart failure. However, the physiological role, activation status, and target genes of MR in the heart are poorly known. Because ligand-free steroid receptors are typically cytoplasmic and translocate to the nucleus upon ligand binding, we examined the subcellular localization of MR under different corticosteroid levels using subcellular fractionation and immunostaining. Our results demonstrate that MR is a chromatin-bound factor in mouse left ventricle and in a cultured model of cardiomyocytes, HL-1 cells, regardless of circulating corticosteroid levels. Immunohistochemical localization of MR in human heart confirms the subcellular localization pattern. Mutation of nuclear localization signals (NLSs) demonstrates that MR constitutive nuclear localization mainly depends on the synergistic contribution of NLS0 and NLS1. Constitutive nuclear localization in HL-1 cells can be reverted by cotransfection of heat shock protein 90. Heat shock protein 90 expression levels in the mouse heart and HL-1 cells are lower than those found in other tissues, suggesting that low levels of cochaperones render MR NLSs hyperactive in cardiomyocytes. Even though MR is constitutively nuclear, corticosteroids still control the transactivation properties of the receptor in a model promoter, although other MR ligand-independent activities cannot be excluded.
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Affiliation(s)
- Iván Hernández-Díaz
- Departamento de Fisiología, Facultad de Medicina, Universidad de La Laguna, La Laguna 38071, Spain
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19
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Activation of progestin receptors in female reproductive behavior: Interactions with neurotransmitters. Front Neuroendocrinol 2010; 31:157-71. [PMID: 20116396 PMCID: PMC2849835 DOI: 10.1016/j.yfrne.2010.01.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Revised: 01/20/2010] [Accepted: 01/21/2010] [Indexed: 01/22/2023]
Abstract
The steroid hormone, progesterone (P), modulates neuroendocrine functions in the central nervous system resulting in alterations in physiology and reproductive behavior in female mammals. A wide body of evidence indicates that these neural effects of P are predominantly mediated via their intracellular progestin receptors (PRs) functioning as "ligand-dependent" transcription factors in the steroid-sensitive neurons regulating genes and genomic networks. In addition to P, intracellular PRs can be activated by neurotransmitters, growth factors and cyclic nucleotides in a ligand-independent manner via crosstalk and convergence of pathways. Furthermore, recent studies indicate that rapid signaling events associated with membrane PRs and/or extra-nuclear, cytoplasmic PRs converge with classical PR activated pathways in neuroendocrine regulation of female reproductive behavior. The molecular mechanisms, by which multiple signaling pathways converge on PRs to modulate PR-dependent female reproductive behavior, are discussed in this review.
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20
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McCullar JS, Oesterle EC. Cellular targets of estrogen signaling in regeneration of inner ear sensory epithelia. Hear Res 2009; 252:61-70. [PMID: 19450430 PMCID: PMC2975607 DOI: 10.1016/j.heares.2009.01.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2008] [Revised: 01/16/2009] [Accepted: 01/22/2009] [Indexed: 01/19/2023]
Abstract
Estrogen signaling in auditory and vestibular sensory epithelia is a newly emerging focus propelled by the role of estrogen signaling in many other proliferative systems. Understanding the pathways with which estrogen interacts can provide a means to identify how estrogen may modulate proliferative signaling in inner ear sensory epithelia. Reviewed herein are two signaling families, EGF and TGFbeta. Both pathways are involved in regulating proliferation of supporting cells in mature vestibular sensory epithelia and have well characterized interactions with estrogen signaling in other systems. It is becoming increasingly clear that elucidating the complexity of signaling in regeneration will be necessary for development of therapeutics that can initiate regeneration and prevent progression to a pathogenic state.
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Affiliation(s)
- Jennifer S. McCullar
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology-Head and Neck Surgery, University of Washington, CHDD CD176, P.O. Box 357923, Seattle, WA 98195, USA
| | - Elizabeth C. Oesterle
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology-Head and Neck Surgery, University of Washington, CHDD CD176, P.O. Box 357923, Seattle, WA 98195, USA
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21
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Abstract
Ovarian steroid hormones, oestradiol and progesterone, modulate neuroendocrine functions in the central nervous system, resulting in alterations in physiology and behaviour. The classical model of steroid hormone action assumes that these neural effects are predominantly mediated via their intracellular receptors functioning as 'ligand-dependent' transcription factors in the steroid-sensitive neurones regulating genes and genomic networks with profound behavioural consequences. Studies from our laboratory demonstrate that, in addition to their cognate ligands, intracellular steroid receptors can be activated in a 'ligand-independent' manner by the neurotransmitter dopamine, which alters the dynamic equilibrium between neuronal phosphatases and kinases. A high degree of cross-talk between membrane-initiated signalling pathways and the classical intracellular signalling pathways mediates hormone-dependent behaviour in mammals. The molecular mechanisms, by which a multitude of signals converge with steroid receptors to delineate a genomic level of cross-talk in brain and behaviour are discussed.
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Affiliation(s)
- S K Mani
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
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22
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Piekarski DJ, Routman DM, Schoomer EE, Driscoll JR, Park JH, Butler MP, Zucker I. Infrequent low dose testosterone treatment maintains male sexual behavior in Syrian hamsters. Horm Behav 2009; 55:182-9. [PMID: 18992750 PMCID: PMC2662611 DOI: 10.1016/j.yhbeh.2008.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Revised: 09/16/2008] [Accepted: 10/02/2008] [Indexed: 11/25/2022]
Abstract
Testosterone (T) secreted in short pulses several times each day is essential for the maintenance of male sex behavior (MSB) in mammals. Blood T concentrations are relatively low during inter-pulse intervals. Assessment of androgenic influences on MSB of rodents has, with very few exceptions, involved either injections of pure or esterified hormones dissolved in oil or implantation of constant release capsules that generate supraphysiological and/or constantly elevated T concentrations. The minimum daily concentration of T necessary to maintain and restore MSB when T is delivered as a discrete short pulse remains unspecified; nor is it known whether infrequent T pulses in the physiological range sustain MSB. To address these questions, we varied T injection concentrations and frequencies in castrated, sexually-experienced Syrian hamsters. All males injected daily with an aqueous vehicle failed to display the ejaculatory reflex 5 weeks after castration. Once daily 15 microg subcutaneous T injections both maintained and restored MSB, whereas once daily 5 microg T injections resulted in fewer males ejaculating and longer ejaculation latencies. Substantially higher T doses were required to restore MSB in previous studies when T was administered in an oil vehicle. 50 microg T maintained MSB in most hamsters injected once every 4 or 7 days, despite long intervals between injections during which circulating T was undetectable or well below physiological concentrations. Some T regimens that maintained MSB were associated with subnormal seminal vesicle and ventral prostate weights. The demonstration that relatively brief, infrequent elevations of T are sufficient to support MSB provides a useful model to assess the neuroendocrine basis of MSB and raises the possibility that infrequent low dose androgen replacement protocols may restore sex behavior to hypogonadal men without inducing some of the negative side-effects associated with more frequent, higher dose treatments.
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Affiliation(s)
- David J Piekarski
- Department of Psychology, University of California, Berkeley, Berkeley, CA 94720, USA.
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23
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Meisel RL. Doing protein kinase C: membrane estrogen receptor signaling in a neural circuit. Endocrinology 2008; 149:5932-3. [PMID: 19022899 PMCID: PMC2613058 DOI: 10.1210/en.2008-1166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Robert L Meisel
- Department of Neuroscience, 6-145 Jackson Hall, 321 Church Street SE, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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24
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Abstract
Progesterone (P), the most biologically active progestin of ovarian origin, modulates numerous cellular functions in the central nervous system to coordinate physiology and reproduction. The neurobiological activity of P is mediated not by a single form of the progestin receptor (PR), but by two neural isoforms of PRs, PR-A and PR-B. Classical model of P action assumes that these neural effects are primarily mediated via their intracellular PRs, acting as transcriptional regulators, in steroid-sensitive neurons, modulating genes and genomic networks. Evidence has emerged, however, that activation of neural PRs is much more diverse; four distinct classes of molecules, neurotransmitters, peptide growth factors, cyclic nucleotides, and neurosteroids have been shown to activate the PRs via cross-talk and pathway convergence. In addition, rapid signaling events associated with membrane receptors and/or subpopulations of cytoplasmic PRs, via activation of protein kinase cascades, regulate PR gene expression in the cytoplasm independent of PR nuclear action. The increasing in vitro and in vivo evidence of differential transcriptional activities and coregulator interactions between PR-A and PR-B predict that these isoforms could have distinct roles in mediating additional and/or alternate signaling pathways within steroid-sensitive neurons. In this minireview, we evaluate the available data and discuss the possible roles of the isoforms in the regulation of neurobiological processes.
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Affiliation(s)
- Shaila Mani
- Department of Molecular and Cellular Biology, Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, Houston, Texas 77030-3411, USA.
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25
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Dopaminergic activation of estrogen receptors induces fos expression within restricted regions of the neonatal female rat brain. PLoS One 2008; 3:e2177. [PMID: 18478050 PMCID: PMC2359852 DOI: 10.1371/journal.pone.0002177] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Accepted: 04/05/2008] [Indexed: 11/22/2022] Open
Abstract
Steroid receptor activation in the developing brain influences a variety of cellular processes that endure into adulthood, altering both behavior and physiology. Recent data suggests that dopamine can regulate expression of progestin receptors within restricted regions of the developing rat brain by activating estrogen receptors in a ligand-independent manner. It is unclear whether changes in neuronal activity induced by dopaminergic activation of estrogen receptors are also region specific. To investigate this question, we examined where the dopamine D1-like receptor agonist, SKF 38393, altered Fos expression via estrogen receptor activation. We report that dopamine D1-like receptor agonist treatment increased Fos protein expression within many regions of the developing female rat brain. More importantly, prior treatment with an estrogen receptor antagonist partially reduced D1-like receptor agonist-induced Fos expression only within the bed nucleus of the stria terminalis and the central amygdala. These data suggest that dopaminergic activation of estrogen receptors alters neuronal activity within restricted regions of the developing rat brain. This implies that ligand-independent activation of estrogen receptors by dopamine might organize a unique set of behaviors during brain development in contrast to the more wide spread ligand activation of estrogen receptors by estrogen.
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26
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Timmermans-Sprang EPM, Rao NAS, Mol JA. Transactivation of a growth hormone (GH) promoter-luciferase construct in canine mammary cells. Domest Anim Endocrinol 2008; 34:403-10. [PMID: 18262383 DOI: 10.1016/j.domaniend.2007.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Revised: 10/31/2007] [Accepted: 11/11/2007] [Indexed: 11/21/2022]
Abstract
The gene encoding growth hormone (GH) is expressed not only in the pituitary but also in a variety of non-pituitary tissues. In the female dog, progestins are known to stimulate GH expression in the mammary gland. In order to investigate the regulation of the GH gene expression in the mammary gland, we transfected the canine mammary tumor cell line CMT-U229 with 3 different canine GH promoter-luciferase constructs. The constructs, varying in length between 252 bp and 673 bp, were transfected followed by an incubation for 4 h, 24 h and 48 h with cAMP, all-trans-retinoic acid (RA), 3,3',5-triiodothyronine (T3), 1,25-dihydroxy-vitamin D (VitD), progesterone and EGF. Promoter activity was stimulated by cAMP, T3 and RA whereas VitD clearly inhibited gene expression. However, despite the presence of nuclear and membrane receptors for progesterone, no direct effects of progesterone on promoter activity could be demonstrated. It is concluded that progesterone alone has no direct stimulatory effect on GH transcription. This finding is discussed in relation to the slow onset of progesterone-stimulated GH release in vivo and the absence of Pit-1 in canine mammary tissue.
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Affiliation(s)
- Elpetra P M Timmermans-Sprang
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM Utrecht, The Netherlands
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27
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Bass AH, Remage-Healey L. Central pattern generators for social vocalization: androgen-dependent neurophysiological mechanisms. Horm Behav 2008; 53:659-72. [PMID: 18262186 PMCID: PMC2570494 DOI: 10.1016/j.yhbeh.2007.12.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2007] [Revised: 12/04/2007] [Accepted: 12/10/2007] [Indexed: 12/13/2022]
Abstract
Historically, most studies of vertebrate central pattern generators (CPGs) have focused on mechanisms for locomotion and respiration. Here, we highlight new results for ectothermic vertebrates, namely teleost fish and amphibians, showing how androgenic steroids can influence the temporal patterning of CPGs for social vocalization. Investigations of vocalizing teleosts show how androgens can rapidly (within minutes) modulate the neurophysiological output of the vocal CPG (fictive vocalizations that mimic the temporal properties of natural vocalizations) inclusive of their divergent actions between species, as well as intraspecific differences between male reproductive morphs. Studies of anuran amphibians (frogs) demonstrate that long-term steroid treatments (wks) can masculinize the fictive vocalizations of females, inclusive of its sensitivity to rapid modulation by serotonin. Given the conserved organization of vocal control systems across vertebrate groups, the vocal CPGs of fish and amphibians provide tractable models for identifying androgen-dependent events that are fundamental to the mechanisms of vocal motor patterning. These basic mechanisms can also inform our understanding of the more complex CPGs for vocalization, and social behaviors in general, that have evolved among birds and mammals.
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Affiliation(s)
- Andrew H Bass
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853, USA.
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28
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Blaustein JD. Neuroendocrine regulation of feminine sexual behavior: lessons from rodent models and thoughts about humans. Annu Rev Psychol 2008; 59:93-118. [PMID: 17678443 DOI: 10.1146/annurev.psych.59.103006.093556] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Much has been learned concerning the neuroendocrine processes and cellular mechanisms by which steroid hormones influence reproductive behaviors in rodents and other animals. In this review, a short discussion of hormones and feminine sexual behavior in some rodent species is followed by an outline of the main principles that have been learned from these studies. Examples are given of the importance of considering the timing of hormone treatments, dosage of hormone, use of a specific hormone, particular class of hormones, or form of hormone, interactions between hormones, route of administration, peripheral factors that influence hormonal response, and the possible mechanisms of action by which hormones and other factors influence sexual behaviors. Although cellular studies in humans are presently impossible to perform, mechanistic studies in rodents may provide clues about the neuroendocrine mechanisms by which hormones act and interact in the brain to influence behavior in all species, including humans.
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Affiliation(s)
- Jeffrey D Blaustein
- Center for Neuroendocrine Studies, Neuroscience and Behavior Program and Psychology Department, University of Massachusetts, Amherst, Massachusetts 01003-9271, USA.
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29
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Bass AH. Steroid-dependent plasticity of vocal motor systems: Novel insights from teleost fish. ACTA ACUST UNITED AC 2008; 57:299-308. [PMID: 17524490 DOI: 10.1016/j.brainresrev.2007.04.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2007] [Revised: 04/18/2007] [Accepted: 04/18/2007] [Indexed: 11/28/2022]
Abstract
Vocal communication is a trait shared by most vertebrates. Non-mammalian model systems have provided exquisite examples of how motor and sensory systems, respectively, produce and encode the physical attributes of acoustic communication signals that play essential roles in mediating the dynamics of social behavior. These same models, mainly developed for a few species of fish, amphibians and birds, have proven to be equally important for demonstrating how steroids and other hormones shape the neural mechanisms of vocal communication. This review mainly considers recent studies in teleost fish demonstrating the role of steroids in the rapid modulation of the firing properties of a central pattern generator for vocalization. Thus, steroids, like other classes of neurochemicals, can play an instrumental role in reshaping the neurophysiological coding of motor patterning, in this case for social signaling behavior.
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Affiliation(s)
- A H Bass
- Department of Neurobiology and Behavior, Seeley G. Mudd Hall, Cornell University, Ithaca, NY 14853, USA.
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30
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Bezdickova M, Molikova R, Bebarova L, Kolar Z. DISTRIBUTION OF NUCLEAR RECEPTORS FOR STEROID HORMONES IN THE HUMAN BRAIN: A PRELIMINARY STUDY. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2007; 151:69-71. [PMID: 17690743 DOI: 10.5507/bp.2007.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Expression of the nuclear steroid hormone receptors (SHR) within certain parts of the human brain has been described by many authors. However, a comprehensive analysis of SHR expression in the human brain still has not been performed. AIM To investigate the expression of SHR in different anatomical areas of the brain, especially within the neocortex. METHOD Immunohistochemical expression of estrogen receptors (ER), progesterone receptors (PR) and androgen receptors (AR) in different regions of the human brain was examined. RESULTS Nuclear expression of the AR was found in the mamillary body, praecentral gyrus and hippocampus of males. The same expression in analysed structures of female was not found. The expression of ER and PR was not observed. CONCLUSIONS The analysis revealed unexpected localization of SHR within the brain cortex, which could be the first step to the explanation of SHR action in brain as an interrelationship to function and behaviour. These results indicate on the possibility of SHR detection in post-mortal brain.
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Affiliation(s)
- Marcela Bezdickova
- Department of Anatomy, Faculty of Medicine and Dentistry, Palacký University, Olomouc, Czech Republic.
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31
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Costantini RM, Park JH, Beery AK, Paul MJ, Ko JJ, Zucker I. Post-castration retention of reproductive behavior and olfactory preferences in male Siberian hamsters: role of prior experience. Horm Behav 2007; 51:149-55. [PMID: 17078953 DOI: 10.1016/j.yhbeh.2006.09.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Revised: 09/20/2006] [Accepted: 09/22/2006] [Indexed: 10/24/2022]
Abstract
Reproductive behavior of virtually all adult male rodents is dependent on concurrent availability of gonadal steroids. The ejaculatory reflex is incompatible with long-term absence of testicular steroids and typically disappears within 3 weeks after castration. Male Siberian hamsters are an exception to this rule; mating culminating in the ejaculatory reflex occurs as many as 6 months after castration (persistent copulation). The emergence of persistent copulation many weeks after gonadectomy is here shown not to require repeated post-castration sexual experience. Preoperative sexual experience, on the other hand, significantly increases the percent of males that copulate after gonadectomy, but is not required for the emergence of this trait in 25% of males. Castration prior to puberty prevents persistent copulation in all individuals in adulthood. Persistent copulators, unlike males that cease mating activity after castration, prefer the odors of estrous over non-estrous females when tested 4 months after castration and 7 weeks after the last mating test. Neural circuits of persistent copulators retain the ability to mediate male sex behavior and preferences for female odors in the complete absence of gonadal steroids; they are influenced by preoperative sexual experience and organizational effects of gonadal hormones at the time of puberty.
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Affiliation(s)
- Ruth M Costantini
- Department of Integrative Biology, University of California, Berkeley, CA 94720, USA
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32
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Mendez P, Wandosell F, Garcia-Segura LM. Cross-talk between estrogen receptors and insulin-like growth factor-I receptor in the brain: cellular and molecular mechanisms. Front Neuroendocrinol 2006; 27:391-403. [PMID: 17049974 DOI: 10.1016/j.yfrne.2006.09.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2006] [Revised: 08/11/2006] [Accepted: 09/01/2006] [Indexed: 01/02/2023]
Abstract
Accumulating evidence suggests that insulin-like growth factor-I (IGF-I) and estradiol interact to regulate neural function. In this review, we focus on the cellular and molecular mechanisms involved in this interaction. The expression of estrogen receptors (ERs) and IGF-I receptor is cross-regulated in the central nervous system and many neurons and astrocytes coexpress both receptors. Furthermore, estradiol activates IGF-I receptor and its intracellular signaling. This effect may involve classical ERs since recent findings suggest that ERalpha may affect IGF-I actions in the brain by a direct interaction with some of the components of IGF-I signaling. In turn, IGF-I may regulate ER transcriptional activity in neuronal cells. In conclusion, ERs appear to be part of the signaling mechanism of IGF-I, and IGF-I receptor part of the mechanism of estradiol signaling in the nervous system.
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Affiliation(s)
- Pablo Mendez
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), E-28002 Madrid, Spain
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33
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Aguilar R, Bellido C, Garrido-Gracia JC, Alonso R, Sánchez-Criado JE. Estradiol and its membrane-impermeable conjugate estradiol-BSA inhibit tamoxifen-stimulated prolactin secretion in incubated rat pituitaries. Reproduction 2006; 131:763-9. [PMID: 16595727 DOI: 10.1530/rep.1.00807] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In the absence of estrogen (E), the selective E receptor modulator tamoxifen (TX) has two agonist effects in the rat pituitary: induction of progesterone receptor (PR)-dependent GnRH self-priming in the gonadotrope, and stimulation of prolactin (PRL) secretion in the lactotrope. TX-induced gonadotropin (GnRH) self-priming is absent when 10(-8) M estradiol-17beta (E2) is added to the incubation medium of pituitaries from TX-treated rats. The present experiments investigated whether PR-independent PRL release into the incubation medium of pituitaries from TX-treated ovariectomized (OVX) rats was affected by E2, and the effect of different ER ligands (ICI182780, TX, estradiol-17alpha, E2 -BSA) on TX-stimulated PRL secretion. Moreover, the effect of E2 on TRH-stimulated PRL secretion in pituitaries collected from estradiol benzoate- and TX-treated OVX rats was studied. It was found that: i) incubation with E2 supressed the PRL releasing effect of injected TX; ii) whereas coincubation with the pure anti-E type II ICI182780 antagonized the inhibitory effect of E2, coincubation with the anti-E type I TX did not; iii) estradiol-17alpha lacked inhibitory action, whereas a dose-dependent inhibitory effect of both E2 and E2 -BSA was noticed; and iv) TRH stimulatory effect on PRL release in pituitaries from TX-treated rats was blocked by addition of E2 to the medium. Taken together, these data argue in favor of the presence of specific membrane recognition sites for E in the lactotrope involved in steroid-specific E2 inhibition of TX-stimulated PRL secretion.
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Affiliation(s)
- R Aguilar
- Department of Cellular Biology, Physiology and Immunology, University of Córdoba Avda, Menendez Pidal s/n, 14004 Córdoba, Spain
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34
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Garrido-Gracia JC, Bellido C, Aguilar R, Sánchez-Criado JE. Protein kinase C cross-talk with gonadotrope progesterone receptor is involved in GnRH-induced LH secretion. J Physiol Biochem 2006; 62:35-42. [PMID: 16909930 DOI: 10.1007/bf03165804] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In the absence of progesterone (P), the anti-P at the receptor RU486 reduces basal and GnRH-stimulated LH secretion both in vivo and in vitro, demonstrating the existence of a ligand-independent activation of progesterone receptor (LIAPR). The aim of the present study was to determine which component of the intracellular LH secretory pathway activated by GnRH is responsible for LIAPR. To do this, anterior pituitary dispersed cells from female rats in proestrus, cultured in the presence of 17beta-estradiol, were incubated with activators or inhibitors of PKC, cAMP-PKA signalling pathways or intracellular calcium (Ca2+) traffic, in the presence or absence of RU486. Results showed that RU486 reduced both GnRH- and the PKC activator PMA-induced LH secretion. In GnRH-stimulated cells incubated with the PKC inhibitor BIS-I or treated with PMA "overnight", RU486 had no effect on reduced LH secretion, nor on stimulated LH secretion elicited by the Ca2+ ionophore ionomycin. Moreover, when GnRH- or PMA-treated cells were co-incubated with 1 microM of the L-type Ca2+ channel blocker nifedipine or the intracellular Ca2+ chelator BAPTA-AM, RU486 potentiated the expected inhibition of these drugs on LH secretion. Activation (forskolin, 8-Br-cAMP) or inhibition (MDL-12,330A) of the cAMP-PKA signalling cascade affected neither the GnRH- and PMA-induced increase of LH secretion nor the reduction of LH secretion due to RU486. Taken together, the data point to the existence of a Ca2+ -independent PKC-PR cross-talk mechanism as part of the intracellular signalling of GnRH-stimulated LH secretion.
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Affiliation(s)
- J C Garrido-Gracia
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Avda. Menéndez Pidal s/n, 14004 Córdoba, Spain.
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35
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Dubal DB, Rau SW, Shughrue PJ, Zhu H, Yu J, Cashion AB, Suzuki S, Gerhold LM, Bottner MB, Dubal SB, Merchanthaler I, Kindy MS, Wise PM. Differential modulation of estrogen receptors (ERs) in ischemic brain injury: a role for ERalpha in estradiol-mediated protection against delayed cell death. Endocrinology 2006; 147:3076-84. [PMID: 16527848 DOI: 10.1210/en.2005-1177] [Citation(s) in RCA: 153] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Estradiol enhances plasticity and survival of the injured brain. Our previous work demonstrates that physiological levels of estradiol protect against cerebral ischemia in the young and aging brain through actions involving estrogen receptors (ERs) and alterations in gene expression. The major goal of this study was to establish mechanisms of neuroprotective actions induced by low levels of estradiol. We first examined effects of estradiol on the time-dependent evolution of ischemic brain injury. Because estradiol is known to influence apoptosis, we hypothesized that it acts to decrease the delayed phase of cell death observed after middle cerebral artery occlusion (MCAO). Furthermore, because ERs are pivotal to neuroprotection, we examined the temporal expression profiles of both ER subtypes, ERalpha and ERbeta, after MCAO and delineated potential roles for each receptor in estradiol-mediated neuroprotection. We quantified cell death in brains at various times after MCAO and analyzed ER expression by RT-PCR, in situ hybridization, and immunohistochemistry. We found that during the first 24 h, the mechanisms of estradiol-induced neuroprotection after MCAO are limited to attenuation of delayed cell death and do not influence immediate cell death. Furthermore, we discovered that ERs exhibit distinctly divergent profiles of expression over the evolution of injury, with ERalpha induction occurring early and ERbeta modulation occurring later. Finally, we provide evidence for a new and functional role for ERalpha in estradiol-mediated protection of the injured brain. These findings indicate that physiological levels of estradiol protect against delayed cell death after stroke-like injury through mechanisms requiring ERalpha.
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Affiliation(s)
- Dena B Dubal
- Department of Physiology, University of Kentucky College of Medicine, Lexington, Kentucky 40536, USA
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36
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Mani SK, Reyna AM, Chen JZ, Mulac-Jericevic B, Conneely OM. Differential response of progesterone receptor isoforms in hormone-dependent and -independent facilitation of female sexual receptivity. Mol Endocrinol 2006; 20:1322-32. [PMID: 16484336 DOI: 10.1210/me.2005-0466] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Neurobehavioral effects of progesterone are mediated primarily by its interaction with neural progesterone receptors (PRs), expressed as PR-A and PR-B protein isoforms. Whereas the expression of two isoforms in the neural tissues is suggestive of their selective cellular responses and modulation of distinct subsets of PR-induced target genes, the role of individual isoforms in brain and behavior is unknown. We have previously demonstrated a critical role for PRs as transcriptional mediators of progesterone (ligand-dependent), and dopamine (ligand-independent)-facilitated female reproductive behavior in female mice lacking both the isoforms of PR. To further elucidate the selective contribution of the individual PR isoforms in female sexual receptive behavior, we used the recently generated PR-A and PR-B isoform-specific null mutant mice. We present evidence for differential responses of each isoform to progesterone and dopamine agonist, SKF 81297 (SKF), and demonstrate a key role for PR-A isoform in both hormone-dependent and -independent facilitation of sexual receptive behavior. Interestingly, whereas both the isoforms were essential for SKF-facilitated sexual behavior, PR-A appeared to play a more important role in the 8-bromo-cAMP-facilitated lordosis response, raising the possibility of distinct intracellular signaling pathways mediating the responses. Finally, we also demonstrate that antiprogestin, RU38486, was an effective inhibitor of PR-A-mediated, progesterone-dependent, but not SKF or 8-bromo-cAMP-dependent sexual receptivity. The data reveal the selective contributions of individual isoforms to the signaling pathways mediating female reproductive behavior.
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Affiliation(s)
- Shaila K Mani
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030, USA.
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Garcia-Segura LM, Sanz A, Mendez P. Cross-talk between IGF-I and estradiol in the brain: focus on neuroprotection. Neuroendocrinology 2006; 84:275-9. [PMID: 17124377 DOI: 10.1159/000097485] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2006] [Accepted: 10/17/2006] [Indexed: 12/27/2022]
Abstract
The actions of estradiol in the brain involve the interaction with growth factors, such as insulin-like growth factor-I (IGF-I). Many cells in the brain coexpress receptors for estradiol (ERs) and IGF-I (IGF-IR) and both factors interact to regulate neural function. Several studies have shown that there is an interaction of IGF-IR and ERs in neuroprotection. Neuroprotective effects of estradiol are blocked by the inhibition of IGF-IR signaling, while the neuroprotective effects of IGF-I are blocked by the inhibition of ER signaling. These findings suggest that the neuroprotective actions of estradiol and IGF-I after brain injury depend on the coactivation of both ERs and IGF-IR in neural cells. The relationship of ERalpha with IGF-IR through the phosphatidylinositol 3-kinase/Akt/glycogen synthase kinase 3beta (PI3K/Akt/GSK3) signaling pathway may represent the point of convergence used by estradiol and IGF-I to cooperatively promote neuroprotection. Administration of estradiol to ovariectomized rats results in the association of ERalpha with IGF-IR and with components of the PI3K/Akt/GSK3 signaling pathway and in the regulation of the activity of Akt and GSK3 in the brain. Conversely, IGF-I regulates ERalpha transcriptional activity in neuroblastoma cells and the PI3K/Akt/GSK3 signaling pathway is involved in this effect.
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Affiliation(s)
- Luis M Garcia-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain.
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Yang X, Liu D, Murray TJ, Mitchell GC, Hesterman EV, Karchner SI, Merson RR, Hahn ME, Sherr DH. The aryl hydrocarbon receptor constitutively represses c-myc transcription in human mammary tumor cells. Oncogene 2005; 24:7869-81. [PMID: 16091746 DOI: 10.1038/sj.onc.1208938] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The aryl hydrocarbon receptor (AhR) is an environmental carcinogen-activated transcription factor associated with tumorigenesis. High levels of apparently active AhR characterize a variety of tumors, even in the absence of environmental ligands. Despite this association between transformation and AhR upregulation, little is known of the transcriptional consequences of constitutive AhR activation. Here, the effects of constitutively active and environmental ligand-induced AhR on c-myc, an oncogene whose promoter contains six AhR-binding sites (AhREs (aryl hydrocarbon response elements)), were investigated. A reporter containing the human c-myc promoter, with its six AhREs and two NF-kappaB-binding sites, was constructed. This vector, and variants with deletions in the NF-kappaB and/or AhR-binding sites, was transfected into a human breast cancer cell line, Hs578T, which expresses high levels of apparently active, nuclear AhR. Results indicate that: (1) the AhR constitutively binds the c-myc promoter; (2) there is a low but significant baseline level of c-myc promoter activity, which is not regulated by NF-kappaB and is not affected by an environmental AhR ligand; (3) deletion of any one of the AhREs has no effect on constitutive reporter activity, while deletion of all six increases reporter activity approximately fivefold; (4) a similar increase in reporter activity occurs when constitutively active AhR is suppressed by transfection with an AhR repressor plasmid (AhRR); (5) AhRR transfection significantly increases background levels of endogenous c-myc mRNA and c-Myc protein. These results suggest that the AhR influences the expression of c-Myc, a protein critical to malignant transformation.
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Affiliation(s)
- Xinhai Yang
- Department of Environmental Health, Boston University School of Public Health, Boston, MA 02118, USA
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Baum MJ. Possible contribution of neonatal ligand-independent activation of estradiol receptors to male-typical sexual differentiation of brain and behavior. Endocrinology 2005; 146:3702-4. [PMID: 16105829 DOI: 10.1210/en.2005-0656] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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40
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Hawkins MB, Godwin J, Crews D, Thomas P. The distributions of the duplicate oestrogen receptors ER-beta a and ER-beta b in the forebrain of the Atlantic croaker (Micropogonias undulatus): evidence for subfunctionalization after gene duplication. Proc Biol Sci 2005; 272:633-41. [PMID: 15817438 PMCID: PMC1564083 DOI: 10.1098/rspb.2004.3008] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Teleost fishes have three distinct oestrogen receptor (ER) subtypes: ER-alpha, ER-beta a (or ER-gamma) and ER-beta b. ER-beta a and ER-beta b arose from a duplication of an ancestral ER-beta gene early in the teleost lineage. Here, we describe the distribution of the three ER mRNAs in the hypothalamus and cerebellum of the Atlantic croaker to address two issues: the specific functions of multiple ERs in the neuroendocrine system and the evolution and fate of duplicated genes. ER-alpha was detected in nuclei of the preoptic area (POA) and hypothalamus previously shown to possess ER-alphas in teleosts. AcER-beta b, but not ER-beta a, labelling was detected in the magnocellular neurons of the POA, nucleus posterior tuberis, the nucleus recessus posterior and cerebellum. By contrast, acER-beta a, but not ER-beta b, was detected in the dorsal anterior parvocellular POA and suprachiasmatic nucleus. Both ER-betas were found in posterior parvocellular and ventral anterior POA nuclei, the ventral hypothalamus, and periventricular dorsal hypothalamus. The differences we observed in ER subtype mRNA distribution within well-characterized brain nuclei suggest that ER-beta a and ER-beta b have distinct functions in the neuroendocrine control of reproduction and behaviour, and provide evidence that the teleost ER-beta paralogues have partitioned functions of the ancestral ER-beta gene they shared with tetrapods.
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Affiliation(s)
- M B Hawkins
- Marine Science Institute, University of Texas at Austin, Port Aransas, TX 78373, USA.
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41
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Miller NR, Jover T, Cohen HW, Zukin RS, Etgen AM. Estrogen can act via estrogen receptor alpha and beta to protect hippocampal neurons against global ischemia-induced cell death. Endocrinology 2005; 146:3070-9. [PMID: 15817665 DOI: 10.1210/en.2004-1515] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Estradiol at physiological concentrations intervenes in apoptotic death cascades and ameliorates neuronal death in experimental models of focal and global ischemia. The cellular targets that mediate estradiol protection of hippocampal neurons in global ischemia are, however, unclear. The present study examined the hypothesis that estradiol protects hippocampal neurons in ovariectomized rats via estrogen receptor (ER)alpha and/or beta. Estradiol (14 d pretreatment) afforded robust protection of CA1 neurons against global ischemia-induced death. The broad-spectrum ER antagonist ICI 182,780 (intracerebroventricularly, 0 and 12 h after ischemia) abolished estrogen protection, consistent with a role for ERs. To evaluate the potential roles of ERalpha vs. ERbeta in estrogen protection, we administered subtype-selective agonists for 14 d before and 7 d after ischemia. The ERalpha-selective agonist propyl pyrazole triol (PPT, 10 mg/kg) and ERbeta-selective agonist WAY 200070-3 (1 mg/kg) produced nearly complete protection of CA1 neurons in approximately 50% of the animals. PPT, but not WAY 200070-3, at doses used for protection, elicited lordosis, induced negative feedback inhibition of LH release, and reduced weight gain. These findings establish the efficacy of the PPT dose in neuroendocrine assays and specificity of WAY 200070-3 for ERbeta. We also examined the ability of estradiol and neuronal injury to regulate ERalpha and ERbeta expression. Both estradiol and global ischemia markedly increased ERalpha, but not ERbeta, protein in CA1. These data indicate that estradiol can act via ERalpha and ERbeta to protect CA1 neurons from global ischemia-induced death and that both estradiol and global ischemia modulate ERalpha expression in hippocampal CA1.
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Affiliation(s)
- Nora R Miller
- Department of Obstetrics, Gynecology and Women's Health, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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Abstract
Sex differences in the brain and behaviour are mostly a result of transient increases in testosterone during the perinatal period. Testosterone influences brain development primarily through aromatization to oestradiol and subsequent binding to oestrogen receptors. Although some studies report that steroid hormones regulate the expression of the inducible transcription factor, Fos, in developing brain, it is not known if there is a sex difference in Fos expression. Changes in Fos protein can be used as an indicator of neuronal/genomic activity. Thus, it provides a useful tool to identify brain regions responding directly or indirectly to steroid hormones. In a first experiment, we examined Fos protein expression in the developing male and female rat brain using western immunoblotting. Dissections were taken from male and female rat pups on the day of birth (postnatal day 0; PN 0), PN1, PN5, PN11 or PN20. Although there was no difference on PN 0, males expressed significantly greater levels of Fos protein on PN1, PN5 and PN20. In a second experiment, we localized the sex difference in Fos protein expression using immunocytochemistry. We found that males expressed significantly higher levels of Fos within a variety of brain regions. These data indicate a sex difference in Fos protein expression during brain development, suggesting a potential role for Fos in differentiating male from female rat brain.
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Affiliation(s)
- K M Olesen
- Department of Psychology, University of Wisconsin, Madison, WI 53706, USA
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Jacobsen BM, Schittone SA, Richer JK, Horwitz KB. Progesterone-independent effects of human progesterone receptors (PRs) in estrogen receptor-positive breast cancer: PR isoform-specific gene regulation and tumor biology. Mol Endocrinol 2004; 19:574-87. [PMID: 15563544 DOI: 10.1210/me.2004-0287] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Progesterone receptors (PRs) are prognostic markers in breast cancers irrespective of the patient's progestational status. However, there are two PR isoforms, PR-A and PR-B, that are equimolar in the normal breast but dysregulated in advanced disease. Postmenopausal, tamoxifen-treated patients with estrogen receptor (ER)-positive, PR-A-rich tumors have much faster disease recurrence than patients with PR-B-rich tumors. To study the mechanisms we engineered ER+ breast cancer cells that express each PR isoform under control of an inducible promoter. We identified 79 genes regulated by progesterone (P), mainly by PR-B, and 51 genes regulated without progesterone, mainly by PR-A. Only nine genes were regulated with and without ligand, leading to definition of three classes: I) genes regulated only by liganded PR; II) genes regulated only by unliganded PR; III) genes regulated by both. Unliganded PR-A and PR-B differentially regulate genes that coordinate extracellular signaling pathways and influence tumor cell biology. Indeed, in the absence of P, compared with ER+/PR-B+ or PR- cells, ER+, PR-A+ cells exhibit an aggressive phenotype, are more adhesive to an extracellular matrix, and are more migratory. Additionally, unliganded PR-A and PR-B both inhibit cell growth and provoke resistance to Taxol-induced apoptosis. We propose that PR-A:PR-B ratios, even in the absence of P, influence the biology and treatment response of ER+ tumors, that PR-A isoforms are functionally dominant in P-deficient states, and that PR-A rich tumors are especially aggressive.
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Affiliation(s)
- Britta M Jacobsen
- Department of Medicine, University of Colorado Health Sciences Center, Aurora, Colorado 80045, USA.
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Patchev VK, Schroeder J, Goetz F, Rohde W, Patchev AV. Neurotropic action of androgens: principles, mechanisms and novel targets. Exp Gerontol 2004; 39:1651-60. [PMID: 15582281 DOI: 10.1016/j.exger.2004.07.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2004] [Accepted: 07/07/2004] [Indexed: 11/20/2022]
Abstract
The importance of androgen signaling is well recognized for numerous aspects of central nervous system (CNS) function, ranging from sex-specific organization of neuroendocrine and behavioral circuits to adaptive capacity, resistance and repair. Nonetheless, concepts for the therapeutic use of androgens in neurological and mental disorders are far from being established. This review outlines some critical issues which interfere with decisions on the suitability of androgens as therapeutic agents for CNS conditions. Among these, sex-specific organization of neural substrates and resulting differential responsiveness to endogenous gonadal steroids, convergence of steroid hormone actions on common molecular targets, co-presence of different sex steroid receptors in target neuronal populations, and in situ biotransformation of natural androgens apparently pose the principal obstacles for the characterization of specific neurotropic effects of androgens. Additional important, albeit less explored aspects consist in insufficient knowledge about molecular targets in the CNS which are under exclusive or predominant androgen control. Own experimental data illustrate the variability of pharmacological effects of natural and synthetic androgens on CNS functions of adaptive relevance, such as sexual behavior, anxiety and endocrine responsiveness to stress. Finally, we present results from an analysis of the consequences of aging for the rat brain transcriptome and examination of the influence of androgens on differentially expressed genes with presumable significance in neuropathology.
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Affiliation(s)
- Vladimir K Patchev
- Male Health Care 2, Corporate Research Gynecology and Andrology, Schering AG/Jenapharm, Otto-Schott-Str. 15, D-07745 Jena, Germany.
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Abstract
'Classical' genomic progesterone receptors appear relatively late in phylogenesis, i.e. it is only in birds and mammals that they are detectable. In the different species, they mediate manifold effects regarding the differentiation of target organ functions, mainly in the reproductive system. Surprisingly, we know little about the physiology, endocrinology, and pharmacology of progesterone and progestins in male gender or men respectively, despite the fact that, as to progesterone secretion and serum progesterone levels, there are no great quantitative differences between men and women (at least outside the luteal phase). In a prospective cohort study of 1026 men with and without cardiovascular disease, we were not able to demonstrate any age-dependent change in serum progesterone concentrations. Progesterone influences spermiogenesis, sperm capacitation/acrosome reaction and testosterone biosynthesis in the Leydig cells. Other progesterone effects in men include those on the central nervous system (CNS) (mainly mediated by 5alpha-reduced progesterone metabolites as so-called neurosteroids), including blocking of gonadotropin secretion, sleep improvement, and effects on tumors in the CNS (meningioma, fibroma), as well as effects on the immune system, cardiovascular system, kidney function, adipose tissue, behavior, and respiratory system. A progestin may stimulate weight gain and appetite in men as well as in women. The detection of progesterone receptor isoforms would have a highly diagnostic value in prostate pathology (benign prostatic hypertrophy and prostate cancer). The modulation of progesterone effects on typical male targets is connected with a great pharmacodynamic variability. The reason for this is that, in men, some important effects of progesterone are mediated non-genomically through different molecular biological modes of action. Therefore, the precise therapeutic manipulation of progesterone actions in the male requires completely new endocrine-pharmacological approaches.
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Affiliation(s)
- Jeffrey D Blaustein
- Center for Neuroendocrine Studies, University of Massachusetts, Amherst, Massachusetts 01003-9271, USA.
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