51
|
Vastagh C, Liposits Z. Impact of Proestrus on Gene Expression in the Medial Preoptic Area of Mice. Front Cell Neurosci 2017; 11:183. [PMID: 28725181 PMCID: PMC5495965 DOI: 10.3389/fncel.2017.00183] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 06/15/2017] [Indexed: 11/13/2022] Open
Abstract
The antero-ventral periventricular zone (AVPV) and medial preoptic area (MPOA) have been recognized as gonadal hormone receptive regions of the rodent brain that-via wiring to gonadotropin-releasing hormone (GnRH) neurons-contribute to orchestration of the preovulatory GnRH surge. We hypothesized that neural genes regulating the induction of GnRH surge show altered expression in proestrus. Therefore, we compared the expression of 48 genes obtained from intact proestrous and metestrous mice, respectively, by quantitative real-time PCR (qPCR) method. Differential expression of 24 genes reached significance (p < 0.05). Genes upregulated in proestrus encoded neuropeptides (kisspeptin (KP), galanin (GAL), neurotensin (NT), cholecystokinin (CCK)), hormone receptors (growth hormone secretagogue receptor, μ-opioid receptor), gonadal steroid receptors (estrogen receptor alpha (ERα), progesterone receptor (PR), androgen receptor (AR)), solute carrier family proteins (vesicular glutamate transporter 2, vesicular monoamine transporter 2), proteins of transmitter synthesis (tyrosine hydroxylase (TH)) and transmitter receptor subunit (AMPA4), and other proteins (uncoupling protein 2, nuclear receptor related 1 protein). Proestrus evoked a marked downregulation of genes coding for adenosine A2a receptor, vesicular gamma-aminobutyric acid (GABA) transporter, 4-aminobutyrate aminotransferase, tachykinin precursor 1, NT receptor 3, arginine vasopressin receptor 1A, cannabinoid receptor 1, ephrin receptor A3 and aldehyde dehydrogenase 1 family, member L1. Immunocytochemistry was used to visualize the proteins encoded by Kiss1, Gal, Cck and Th genes in neuronal subsets of the AVPV/MPOA of the proestrous mice. The results indicate that gene expression of the AVPV/MPOA is significantly modified at late proestrus including genes that code for neuropeptides, gonadal steroid hormone receptors and synaptic vesicle transporters. These events support cellular and neuronal network requirements of the positive estradiol feedback action and contribute to preparation of the GnRH neuron system for the pre-ovulatory surge release.
Collapse
Affiliation(s)
- Csaba Vastagh
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of SciencesBudapest, Hungary
| | - Zsolt Liposits
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of SciencesBudapest, Hungary.,Department of Neuroscience, Faculty of Information Technology and Bionics, Pázmány Péter Catholic UniversityBudapest, Hungary
| |
Collapse
|
52
|
Moore AM, Campbell RE. Polycystic ovary syndrome: Understanding the role of the brain. Front Neuroendocrinol 2017; 46:1-14. [PMID: 28551304 DOI: 10.1016/j.yfrne.2017.05.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 05/19/2017] [Accepted: 05/20/2017] [Indexed: 01/09/2023]
Abstract
Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder and the leading cause of anovulatory infertility. Characterised by hyperandrogenism, menstrual dysfunction and polycystic ovaries, PCOS is a broad-spectrum disorder unlikely to stem from a single common origin. Although commonly considered an ovarian disease, the brain is now a prime suspect in both the ontogeny and pathology of PCOS. We discuss here the neuroendocrine impairments present in PCOS that implicate involvement of the brain and review evidence gained from pre-clinical models of the syndrome about the specific brain circuitry involved. In particular, we focus on the impact that developmental androgen excess and adult hyperandrogenemia have in programming and regulating brain circuits important in the central regulation of fertility. The studies discussed here provide compelling support for the importance of the brain in PCOS ontogeny and pathophysiology and highlight the need for a better understanding of the underlying mechanisms involved.
Collapse
Affiliation(s)
- Aleisha M Moore
- Department of Neurobiology and Anatomical Sciences, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Rebecca E Campbell
- Centre for Neuroendocrinology and Department of Physiology, Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand.
| |
Collapse
|
53
|
Chachlaki K, Malone SA, Qualls-Creekmore E, Hrabovszky E, Münzberg H, Giacobini P, Ango F, Prevot V. Phenotyping of nNOS neurons in the postnatal and adult female mouse hypothalamus. J Comp Neurol 2017; 525:3177-3189. [PMID: 28577305 DOI: 10.1002/cne.24257] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 05/01/2017] [Accepted: 05/19/2017] [Indexed: 12/27/2022]
Abstract
Neurons expressing nitric oxide (NO) synthase (nNOS) and thus capable of synthesizing NO play major roles in many aspects of brain function. While the heterogeneity of nNOS-expressing neurons has been studied in various brain regions, their phenotype in the hypothalamus remains largely unknown. Here we examined the distribution of cells expressing nNOS in the postnatal and adult female mouse hypothalamus using immunohistochemistry. In both adults and neonates, nNOS was largely restricted to regions of the hypothalamus involved in the control of bodily functions, such as energy balance and reproduction. Labeled cells were found in the paraventricular, ventromedial, and dorsomedial nuclei as well as in the lateral area of the hypothalamus. Intriguingly, nNOS was seen only after the second week of life in the arcuate nucleus of the hypothalamus (ARH). The most dense and heavily labeled population of cells was found in the organum vasculosum laminae terminalis (OV) and the median preoptic nucleus (MEPO), where most of the somata of the neuroendocrine neurons releasing GnRH and controlling reproduction are located. A great proportion of nNOS-immunoreactive neurons in the OV/MEPO and ARH were seen to express estrogen receptor (ER) α. Notably, almost all ERα-immunoreactive cells of the OV/MEPO also expressed nNOS. Moreover, the use of EYFPVglut2 , EYFPVgat , and GFPGad67 transgenic mouse lines revealed that, like GnRH neurons, most hypothalamic nNOS neurons have a glutamatergic phenotype, except for nNOS neurons of the ARH, which are GABAergic. Altogether, these observations are consistent with the proposed role of nNOS neurons in physiological processes.
Collapse
Affiliation(s)
- Konstantina Chachlaki
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, U1172, Lille, France.,University of Lille, FHU 1000 days for Health, School of Medicine, Lille, France
| | - Samuel A Malone
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, U1172, Lille, France.,University of Lille, FHU 1000 days for Health, School of Medicine, Lille, France
| | - Emily Qualls-Creekmore
- Departments of Central Leptin Signaling, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana
| | - Erik Hrabovszky
- Institute of Experimental Medicine, Laboratory of Endocrine Neurobiology, Budapest, Hungary
| | - Heike Münzberg
- Departments of Central Leptin Signaling, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana
| | - Paolo Giacobini
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, U1172, Lille, France.,University of Lille, FHU 1000 days for Health, School of Medicine, Lille, France
| | - Fabrice Ango
- Inserm, Laboratory of Development of GABAergic circuit, IGF, U1191, Montpellier, France.,University of Montpellier, CNRS UMR5203, Montpellier, France
| | - Vincent Prevot
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, U1172, Lille, France.,University of Lille, FHU 1000 days for Health, School of Medicine, Lille, France
| |
Collapse
|
54
|
Mosley M, Weathington J, Cortes LR, Bruggeman E, Castillo-Ruiz A, Xue B, Forger NG. Neonatal Inhibition of DNA Methylation Alters Cell Phenotype in Sexually Dimorphic Regions of the Mouse Brain. Endocrinology 2017; 158:1838-1848. [PMID: 28398586 PMCID: PMC5460944 DOI: 10.1210/en.2017-00205] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 03/24/2017] [Indexed: 02/06/2023]
Abstract
Many of the best-studied neural sex differences relate to differences in cell number and are due to the hormonal control of developmental cell death. However, several prominent neural sex differences persist even if cell death is eliminated. We hypothesized that these may reflect cell phenotype "decisions" that depend on epigenetic mechanisms, such as DNA methylation. To test this, we treated newborn mice with the DNA methyltransferase (DNMT) inhibitor zebularine, or vehicle, and examined two sexually dimorphic markers at weaning. As expected, control males had more cells immunoreactive for calbindin-D28k (CALB) in the medial preoptic area (mPOA) and fewer cells immunoreactive for estrogen receptor α (ERα) in the ventrolateral portion of the ventromedial nucleus of the hypothalamus (VMHvl) and the mPOA than did females. Neonatal DNMT inhibition markedly increased CALB cell number in both sexes and ERα cell density in males; as a result, the sex differences in ERα in the VMHvl and mPOA were completely eliminated in zebularine-treated animals. Zebularine treatment did not affect developmental cell death or the total density of Nissl-stained cells at weaning. Thus, a neonatal disruption of DNA methylation apparently has long-term effects on the proportion of cells expressing CALB and ERα, and some of these effects are sex specific. We also found that sex differences in CALB in the mPOA and ERα in the VMHvl persist in mice with a neuron-specific depletion of either Dnmt1 or Dnmt3b, indicating that neither DNMT alone is likely to be required for the sexually dimorphic expression of these markers.
Collapse
Affiliation(s)
- Morgan Mosley
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302
| | - Jill Weathington
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302
| | - Laura R. Cortes
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302
| | - Emily Bruggeman
- Department of Biology, Neuroscience Institute and Center for Obesity Reversal, Georgia State University, Atlanta, Georgia 30302
| | - Alexandra Castillo-Ruiz
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302
| | - Bingzhong Xue
- Department of Biology, Neuroscience Institute and Center for Obesity Reversal, Georgia State University, Atlanta, Georgia 30302
| | - Nancy G. Forger
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302
| |
Collapse
|
55
|
Desroziers E, Brock O, Bakker J. Potential contribution of progesterone receptors to the development of sexual behavior in male and female mice. Horm Behav 2017; 90:31-38. [PMID: 27167606 DOI: 10.1016/j.yhbeh.2016.05.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 05/05/2016] [Indexed: 01/03/2023]
Abstract
We previously showed that estradiol can have both defeminizing and feminizing effects on the developing mouse brain. Pre- and early postnatal estradiol defeminized the ability to show lordosis in adulthood, whereas prepubertal estradiol feminized this ability. Furthermore, we found that estradiol upregulates progesterone receptors (PR) during development, inducing both a male-and female-typical pattern of PR expression in the mouse hypothalamus. In the present study, we took advantage of a newly developed PR antagonist (ZK 137316) to determine whether PR contributes to either male- or female-typical sexual differentiation. Thus groups of male and female C57Bl/6j mice were treated with ZK 137316 or OIL as control: males were treated neonatally (P0-P10), during the critical period for male sexual differentiation, and females were treated prepubertally (P15-P25), during the critical period for female sexual differentiation. In adulthood, mice were tested for sexual behavior. In males, some minor effects of neonatal ZK treatment on sexual behavior were observed: latencies to the first mount, intromission and ejaculation were decreased in neonatally ZK treated males; however, this effect disappeared by the second mating test. By contrast, female mice treated with ZK during the prepubertal period showed significantly less lordosis than OIL-treated females. Mate preferences were not affected in either males or females treated with ZK during development. Taken together, these results suggest a role for PR and thus perhaps progesterone in the development of lordosis behavior in female mice. By contrast, no obvious role for PR can be discerned in the development of male sexual behavior.
Collapse
MESH Headings
- Animals
- Estradiol/metabolism
- Estradiol/pharmacology
- Female
- Feminization
- Gene Expression Regulation, Developmental/drug effects
- Hormone Antagonists/pharmacology
- Male
- Mice
- Mice, Inbred C57BL
- Pregnancy
- Progesterone/metabolism
- Progesterone/pharmacology
- Receptors, Neuropeptide Y/genetics
- Receptors, Neuropeptide Y/metabolism
- Receptors, Progesterone/antagonists & inhibitors
- Receptors, Progesterone/genetics
- Receptors, Progesterone/metabolism
- Receptors, Progesterone/physiology
- Sex Differentiation/drug effects
- Sex Differentiation/genetics
- Sex Differentiation/physiology
- Sexual Behavior, Animal/drug effects
- Sexual Behavior, Animal/physiology
- Steroids/pharmacology
Collapse
Affiliation(s)
| | - Olivier Brock
- GIGA-Neurosciences, University of Liège, 4000 Liège, Belgium
| | - Julie Bakker
- GIGA-Neurosciences, University of Liège, 4000 Liège, Belgium.
| |
Collapse
|
56
|
Origins and Functions of the Ventrolateral VMH: A Complex Neuronal Cluster Orchestrating Sex Differences in Metabolism and Behavior. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1043:199-213. [PMID: 29224096 DOI: 10.1007/978-3-319-70178-3_10] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The neuroendocrine brain or hypothalamus has emerged as one of the most highly sexually dimorphic brain regions in mammals, and specifically in rodents. It is not surprising that hypothalamic nuclei play a pivotal role in controlling sex-dependent physiology. This brain region functions as a chief executive officer or master regulator of homeostatic physiological systems to integrate both external and internal signals. In this review, we describe sex differences in energy homeostasis that arise in one area of the hypothalamus, the ventrolateral subregion of the ventromedial hypothalamus (VMHvl) with a focus on how male and female neurons function in metabolic and behavioral aspects. Because other chapters within this book provide details on signaling pathways in the VMH that contribute to sex differences in metabolism, our discussion will be limited to how the sexually dimorphic VMHvl develops and what key regulators are thought to control the many functional and physiological endpoints attributed to this region. In the last decade, several exciting new studies using state-of-the-art genetic and molecular tools are beginning to provide some understanding as to how specific neurons contribute to the coordinated physiological responses needed by male and females. New technology that combines intersectional spatial and genetic approaches is now allowing further refinement in how we describe, probe, and manipulate critical male and female neurocircuits involved in metabolism.
Collapse
|
57
|
|
58
|
Walker DM, Gore AC. Epigenetic impacts of endocrine disruptors in the brain. Front Neuroendocrinol 2017; 44:1-26. [PMID: 27663243 PMCID: PMC5429819 DOI: 10.1016/j.yfrne.2016.09.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/05/2016] [Accepted: 09/14/2016] [Indexed: 12/12/2022]
Abstract
The acquisition of reproductive competence is organized and activated by steroid hormones acting upon the hypothalamus during critical windows of development. This review describes the potential role of epigenetic processes, particularly DNA methylation, in the regulation of sexual differentiation of the hypothalamus by hormones. We examine disruption of these processes by endocrine-disrupting chemicals (EDCs) in an age-, sex-, and region-specific manner, focusing on how perinatal EDCs act through epigenetic mechanisms to reprogram DNA methylation and sex steroid hormone receptor expression throughout life. These receptors are necessary for brain sexual differentiation and their altered expression may underlie disrupted reproductive physiology and behavior. Finally, we review the literature on histone modifications and non-coding RNA involvement in brain sexual differentiation and their perturbation by EDCs. By putting these data into a sex and developmental context we conclude that perinatal EDC exposure alters the developmental trajectory of reproductive neuroendocrine systems in a sex-specific manner.
Collapse
Affiliation(s)
- Deena M Walker
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1065, New York, NY 10029, USA.
| | - Andrea C Gore
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, and The University of Texas at Austin, Austin, TX 78712, USA; Institute for Neuroscience, The University of Texas at Austin, Austin, TX 78712, USA
| |
Collapse
|
59
|
Sex differences in the brain–an interplay of sex steroid hormones and sex chromosomes. Clin Sci (Lond) 2016; 130:1481-97. [DOI: 10.1042/cs20160299] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 05/17/2016] [Indexed: 12/12/2022]
Abstract
Although considerable progress has been made in our understanding of brain function, many questions remain unanswered. The ultimate goal of studying the brain is to understand the connection between brain structure and function and behavioural outcomes. Since sex differences in brain morphology were first observed, subsequent studies suggest different functional organization of the male and female brains in humans. Sex and gender have been identified as being a significant factor in understanding human physiology, health and disease, and the biological differences between the sexes is not limited to the gonads and secondary sexual characteristics, but also affects the structure and, more crucially, the function of the brain and other organs. Significant variability in brain structures between individuals, in addition to between the sexes, is factor that complicates the study of sex differences in the brain. In this review, we explore the current understanding of sex differences in the brain, mostly focusing on preclinical animal studies.
Collapse
|
60
|
Cornejo MP, Hentges ST, Maliqueo M, Coirini H, Becu-Villalobos D, Elias CF. Neuroendocrine Regulation of Metabolism. J Neuroendocrinol 2016; 28:10.1111/jne.12395. [PMID: 27114114 PMCID: PMC4956544 DOI: 10.1111/jne.12395] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/31/2016] [Accepted: 04/21/2016] [Indexed: 12/29/2022]
Abstract
Given the current environment in most developed countries, it is a challenge to maintain a good balance between calories consumed and calories burned, although maintenance of metabolic balance is key to good health. Therefore, understanding how metabolic regulation is achieved and how the dysregulation of metabolism affects health is an area of intense research. Most studies focus on the hypothalamus, which is a brain area that acts as a key regulator of metabolism. Among the nuclei that comprise the hypothalamus, the arcuate nucleus is one of the major mediators in the regulation of food intake. The regulation of energy balance is also a key factor ensuring the maintenance of any species as a result of the dependence of reproduction on energy stores. Adequate levels of energy reserves are necessary for the proper functioning of the hypothalamic-pituitary-gonadal axis. This review discusses valuable data presented in the 2015 edition of the International Workshop of Neuroendocrinology concerning the fundamental nature of the hormonal regulation of the hypothalamus and the impact on energy balance and reproduction.
Collapse
Affiliation(s)
- Maria P. Cornejo
- Laboratory of Neurophysiology, Multidisciplinary Institute of Cell Biology [IMBICE, dependent on the Argentine Research Council (CONICET), Scientific Research Commission, Province of Buenos Aires (CIC-PBA) and National University of La Plata (UNLP)], La Plata, Argentina
| | - Shane T. Hentges
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Manuel Maliqueo
- Endocrinology and Metabolism Laboratory, Department of Medicine West Division, School of Medicine University of Chile, Santiago de Chile, Chile
| | - Hector Coirini
- Laboratory of Neurobiology, Institute of Biology and Experimental Medicine [(IBYME), dependent on CONICET] and Department of Human Biochemistry, University of Buenos Aires, Buenos Aires, Argentina
| | - Damasia Becu-Villalobos
- Laboratory of Pituitary Regulation, Institute of Biology and Experimental Medicine [(IBYME), dependent on CONICET], Buenos Aires, Argentina
| | - Carol F. Elias
- Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| |
Collapse
|
61
|
Kyi-Tha-Thu C, Okoshi K, Ito H, Matsuda KI, Kawata M, Tsukahara S. Sex differences in cells expressing green fluorescent protein under the control of the estrogen receptor-α promoter in the hypothalamus of mice. Neurosci Res 2015; 101:44-52. [DOI: 10.1016/j.neures.2015.07.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 06/26/2015] [Accepted: 07/08/2015] [Indexed: 01/06/2023]
|