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Wu X, Zhang Z, Li Y, Zhao Y, Ren Y, Tian Y, Hou M, Guo Y, Li Q, Tian W, Jiang R, Zhang Y, Gong Y, Li H, Li G, Liu X, Kang X, Li D, Tian Y. Estrogen promotes gonadotropin-releasing hormone expression by regulating tachykinin 3 and prodynorphin systems in chicken. Poult Sci 2024; 103:103820. [PMID: 38759565 PMCID: PMC11127269 DOI: 10.1016/j.psj.2024.103820] [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: 01/23/2024] [Revised: 04/12/2024] [Accepted: 05/02/2024] [Indexed: 05/19/2024] Open
Abstract
The "KNDy neurons" located in the hypothalamic arcuate nucleus (ARC) of mammals are known to co-express kisspeptin, neurokinin B (NKB), and dynorphin (DYN), and have been identified as key mediators of the feedback regulation of steroid hormones on gonadotropin-releasing hormone (GnRH). However, in birds, the genes encoding kisspeptin and its receptor GPR54 are genomic lost, leaving unclear mechanisms for feedback regulation of GnRH by steroid hormones. Here, the genes tachykinin 3 (TAC3) and prodynorphin (PDYN) encoding chicken NKB and DYN neuropeptides were successfully cloned. Temporal expression profiling indicated that TAC3, PDYN and their receptor genes (TACR3, OPRK1) were mainly expressed in the hypothalamus, with significantly higher expression at 30W than at 15W. Furthermore, overexpression or interference of TAC3 and PDYN can regulate the GnRH mRNA expression. In addition, in vivo and in vitro assays showed that estrogen (E2) could promote the mRNA expression of TAC3, PDYN, and GnRH, as well as the secretion of GnRH/LH. Mechanistically, E2 could dimerize the nuclear estrogen receptor 1 (ESR1) to regulate the expression of TAC3 and PDYN, which promoted the mRNA and protein expression of GnRH gene as well as the secretion of GnRH. In conclusion, these results revealed that E2 could regulate the GnRH expression through TAC3 and PDYN systems, providing novel insights for reproductive regulation in chickens.
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Affiliation(s)
- Xing Wu
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China
| | - Zihao Zhang
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China
| | - Yijie Li
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China
| | - Yudian Zhao
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China
| | - Yangguang Ren
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China
| | - Yixiang Tian
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang 453003, China
| | - Meng Hou
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China
| | - Yulong Guo
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China
| | - Qi Li
- Henan zhumadian agricultural school, zhumadian, 463000, China
| | - Weihua Tian
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou 450046, China
| | - Ruirui Jiang
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou 450046, China
| | - Yanhua Zhang
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou 450046, China
| | - Yujie Gong
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou 450046, China
| | - Hong Li
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou 450046, China
| | - Guoxi Li
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou 450046, China
| | - Xiaojun Liu
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou 450046, China
| | - Xiangtao Kang
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou 450046, China
| | - Donghua Li
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou 450046, China
| | - Yadong Tian
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou 450046, China.
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Torres T, Adam N, Mhaouty-Kodja S, Naulé L. Reproductive function and behaviors: an update on the role of neural estrogen receptors alpha and beta. Front Endocrinol (Lausanne) 2024; 15:1408677. [PMID: 38978624 PMCID: PMC11228153 DOI: 10.3389/fendo.2024.1408677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Accepted: 05/29/2024] [Indexed: 07/10/2024] Open
Abstract
Infertility is becoming a major public health problem, with increasing frequency due to medical, environmental and societal causes. The increasingly late age of childbearing, growing exposure to endocrine disruptors and other reprotoxic products, and increasing number of medical reproductive dysfunctions (endometriosis, polycystic ovary syndrome, etc.) are among the most common causes. Fertility relies on fine-tuned control of both neuroendocrine function and reproductive behaviors, those are critically regulated by sex steroid hormones. Testosterone and estradiol exert organizational and activational effects throughout life to establish and activate the neural circuits underlying reproductive function. This regulation is mediated through estrogen receptors (ERs) and androgen receptor (AR). Estradiol acts mainly via nuclear estrogen receptors ERα and ERβ. The aim of this review is to summarize the genetic studies that have been undertaken to comprehend the specific contribution of ERα and ERβ in the neural circuits underlying the regulation of the hypothalamic-pituitary-gonadal axis and the expression of reproductive behaviors, including sexual and parental behavior. Particular emphasis will be placed on the neural role of these receptors and the underlying sex differences.
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Affiliation(s)
| | | | | | - Lydie Naulé
- Sorbonne Université, CNRS UMR8246, INSERM U1130, Neuroscience Paris Seine – Institut de Biologie Paris Seine, Paris, France
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Peng W, Zhang Y, Song B, Yang P, Liu L. Developmental Delay and Male-Biased Sex Ratio in esr2b Knockout Zebrafish. Genes (Basel) 2024; 15:636. [PMID: 38790265 PMCID: PMC11121336 DOI: 10.3390/genes15050636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/27/2024] [Accepted: 05/15/2024] [Indexed: 05/26/2024] Open
Abstract
The estrogen receptor signaling pathway plays an important role in vertebrate embryonic development and sexual differentiation. There are four major estrogen receptors in zebrafish: esr1, esr2a, esr2b and gper. However, the specific role of different estrogen receptors in zebrafish is not clear. To investigate the role of esr2b in zebrafish development and reproduction, this study utilized TALENs technology to generate an esr2b knockout homozygous zebrafish line. The number of eggs laid by esr2b knockout female zebrafish did not differ significantly from that of wild zebrafish. The embryonic development process of wild-type and esr2b knockout zebrafish was observed, revealing a significant developmental delay in the esr2b knockout zebrafish. Additionally, mortality rates were significantly higher in esr2b knockout zebrafish than in their wild-type counterparts at 24 hpf. The reciprocal cross experiment between esr2b knockout zebrafish and wild-type zebrafish revealed that the absence of esr2b resulted in a decline in the quality of zebrafish oocytes, while having no impact on sperm cells. The knockout of esr2b also led to an abnormal sex ratio in the adult zebrafish population, with a female-to-male ratio of approximately 1:7. The quantitative PCR (qPCR) and in situ hybridization results demonstrated a significant downregulation of cyp19ab1b expression in esr2b knockout embryos compared to wild-type embryos throughout development (at 2 dpf, 3 dpf and 4 dpf). Additionally, the estrogen-mediated induction expression of cyp19ab1b was attenuated, while the estradiol-induced upregulated expression of vtg1 was disrupted. These results suggest that esr2b is involved in regulating zebrafish oocyte development and sex differentiation.
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Affiliation(s)
- Wei Peng
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China; (Y.Z.); (B.S.); (P.Y.); (L.L.)
- State Key Laboratory of Development Biology of Freshwater Fish Sub-Center for Health Aquaculture, Changde 415000, China
| | - Yunsheng Zhang
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China; (Y.Z.); (B.S.); (P.Y.); (L.L.)
- State Key Laboratory of Development Biology of Freshwater Fish Sub-Center for Health Aquaculture, Changde 415000, China
| | - Bolan Song
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China; (Y.Z.); (B.S.); (P.Y.); (L.L.)
- State Key Laboratory of Development Biology of Freshwater Fish Sub-Center for Health Aquaculture, Changde 415000, China
| | - Pinhong Yang
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China; (Y.Z.); (B.S.); (P.Y.); (L.L.)
- State Key Laboratory of Development Biology of Freshwater Fish Sub-Center for Health Aquaculture, Changde 415000, China
| | - Liangguo Liu
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China; (Y.Z.); (B.S.); (P.Y.); (L.L.)
- State Key Laboratory of Development Biology of Freshwater Fish Sub-Center for Health Aquaculture, Changde 415000, China
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Jeseta M, Kalina J, Franzova K, Fialkova S, Hosek J, Mekinova L, Crha I, Kempisty B, Ventruba P, Navratilova J. Cross sectional study on exposure to BPA and its analogues and semen parameters in Czech men. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 345:123445. [PMID: 38325504 DOI: 10.1016/j.envpol.2024.123445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 02/09/2024]
Abstract
Exposure to bisphenols has been found to have adverse effects on male reproductive function in animals. Human exposure to bisphenols is widespread. Bisphenol A (BPA) and its analogues, including bisphenol S (BPS), bisphenol F (BPF), and bisphenol AF (BPAF) are utilized in various consumer products such as food contact materials and dental resins. The effects of these compounds on male fertility and spermatogenesis are unclear and findings from human studies are inconsistent. In this cross-sectional study, we evaluated the influence of BPA, BPS, BPF, BPAF (BPs) measured in semen on number of spermatozoa, total motility, progressive motility, morphology, and DNA fragmentation. We also examined the association of bisphenols (BPs) exposure with patients' occupation. A total of 358 patients aged 17-62 years with BMI 18-42 were included in the study from 2019 to 2021. BPs were extracted using solvent extraction followed by preconcentration step and determined by high-performance liquid chromatography and tandem mass spectrometry (LC/MSMS). Bisphenols were detected in 343 from 349 analysed samples (98.3% of all the samples). In 6 samples, the concentration of all BPs was under the limit of detection and in 20 samples under the limit of quantification. We did not find a statistically significant relationship between occupation and BPs. However, we observed significant correlations between the concentration of BPA and a lower motility and normal morphology. For BPS, a significant correlation with a lower ejaculate volume and a lower total sperm count was found. BPF and BPAF were detected only in 14.3% and 23.9% of samples, respectively. For BPF and BPAF, no significant correlations with spermiogram parameters were observed. Our results show that BPs are widespread in the male population (more than 90% of analysed samples), independently of an occupation and in case of BPA and BPS having a negative impact on spermiogram parameters.
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Affiliation(s)
- Michal Jeseta
- Department of Gynecology and Obstetrics, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic; Department of Veterinary Sciences, Czech University of Life Sciences in Prague, Czech Republic.
| | - Jiri Kalina
- RECETOX Centre, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Katerina Franzova
- Department of Gynecology and Obstetrics, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Sandra Fialkova
- RECETOX Centre, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Jan Hosek
- Veterinary Research Institute, Hudcova 70, Brno, Czech Republic; Department of Molecular Pharmacy, Faculty of Pharmacy, Masaryk University, Brno, Czech Republic
| | - Lenka Mekinova
- Department of Gynecology and Obstetrics, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Igor Crha
- Department of Gynecology and Obstetrics, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic; Department of Health Sciences, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Bartosz Kempisty
- Institute of Veterinary Medicine, Nicolaus Copernicus University, Torun, Poland; Department of Human Morphology and Embryology, Wroclaw Medical University, Poland; Physiology Graduate Faculty, North Carolina State University, Raleigh NC, USA
| | - Pavel Ventruba
- Department of Gynecology and Obstetrics, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Jana Navratilova
- RECETOX Centre, Faculty of Science, Masaryk University, Brno, Czech Republic
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Ethridge SB, Smith MA. Estradiol and Mu opioid-mediated reward: The role of estrogen receptors in opioid use. ADDICTION NEUROSCIENCE 2023; 9:100139. [PMID: 38155959 PMCID: PMC10753849 DOI: 10.1016/j.addicn.2023.100139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/30/2023]
Abstract
Opioid use and opioid use disorder are characterized by sex and gender differences, and some of these differences may be mediated by differences in the hormonal milieu within and across individuals. This review focuses on the role of ovarian hormones, and particularly estradiol, on the endogenous mu opioid receptor system. There is an abundance of data indicating that estradiol influences the activity of endogenous mu opioid peptides, the activation of mu opioid receptors, and the internalization and desensitization of mu opioid receptors. These effects have functional consequences on behaviors mediated by endogenous mu opioid receptor activity and on sensitivity to mu opioid agonists and antagonists. Recent behavioral data suggest these consequences extend to mu opioid reward, and preclinical studies report that estradiol decreases self-administration of mu opioid receptor agonists across a range of experimental conditions. Data collected in human laboratory studies suggest that estradiol may have functionally similar effects in clinical populations, and thus estrogen receptors may be a potential target in the development of novel therapeutics. This review summarizes data from cellular assays to clinical trials to explore how estradiol influences mu opioid receptor activity, as well as potential ways in which estrogen receptors may be targeted to address the problems of opioid use.
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Affiliation(s)
- Sarah B. Ethridge
- Department of Psychology, Program in Neuroscience, Davidson College, Davidson, NC, USA
| | - Mark A. Smith
- Department of Psychology, Program in Neuroscience, Davidson College, Davidson, NC, USA
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Guelfi G, Pasquariello R, Anipchenko P, Capaccia C, Pennarossa G, Brevini TAL, Gandolfi F, Zerani M, Maranesi M. The Role of Genistein in Mammalian Reproduction. Molecules 2023; 28:7436. [PMID: 37959856 PMCID: PMC10647478 DOI: 10.3390/molecules28217436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 11/03/2023] [Accepted: 11/03/2023] [Indexed: 11/15/2023] Open
Abstract
Genistein is a natural compound belonging to flavonoids, having antioxidant, anti-inflammatory, and anti-neoplastic properties. Genistein is considered a phytoestrogen. As such, genistein can bind estrogen receptors (ERα and ERβ), although with a lower affinity than that of estradiol. Despite considerable work, the effects of genistein are not well established yet. This review aims to clarify the role of genistein on female and male reproductive functions in mammals. In females, at a high dose, genistein diminishes the ovarian activity regulating several pathway molecules, such as topoisomerase isoform I and II, protein tyrosine kinases (v-src, Mek-4, ABL, PKC, Syk, EGFR, FGFR), ABC, CFTR, Glut1, Glut4, 5α-reductase, PPAR-γ, mitogen-activated protein kinase A, protein histidine kinase, and recently circulating RNA-miRNA. The effect of genistein on pregnancy is still controversial. In males, genistein exerts an estrogenic effect by inducing testosterone biosynthesis. The interaction of genistein with both natural and synthetic endocrine disruptors has a negative effect on testis function. The positive effect of genistein on sperm quality is still in debate. In conclusion, genistein has a potentially beneficial effect on the mechanisms regulating the reproduction of females and males. However, this is dependent on the dose, the species, the route, and the time of administration.
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Affiliation(s)
- Gabriella Guelfi
- Department of Veterinary Medicine, University of Perugia, 06126 Perugia, Italy; (G.G.); (C.C.); (M.Z.); (M.M.)
| | - Rolando Pasquariello
- Department of Agricultural and Environmental Sciences, University of Milan, 20133 Milano, Italy; (R.P.); (F.G.)
| | - Polina Anipchenko
- Department of Veterinary Medicine, University of Perugia, 06126 Perugia, Italy; (G.G.); (C.C.); (M.Z.); (M.M.)
| | - Camilla Capaccia
- Department of Veterinary Medicine, University of Perugia, 06126 Perugia, Italy; (G.G.); (C.C.); (M.Z.); (M.M.)
| | - Georgia Pennarossa
- Department of Veterinary Medicine and Animal Science, University of Milan, 26900 Lodi, Italy;
| | - Tiziana A. L. Brevini
- Department of Veterinary Medicine and Animal Science, University of Milan, 26900 Lodi, Italy;
| | - Fulvio Gandolfi
- Department of Agricultural and Environmental Sciences, University of Milan, 20133 Milano, Italy; (R.P.); (F.G.)
| | - Massimo Zerani
- Department of Veterinary Medicine, University of Perugia, 06126 Perugia, Italy; (G.G.); (C.C.); (M.Z.); (M.M.)
| | - Margherita Maranesi
- Department of Veterinary Medicine, University of Perugia, 06126 Perugia, Italy; (G.G.); (C.C.); (M.Z.); (M.M.)
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Kiyokage E, Ichikawa S, Horie S, Hayashi S, Toida K. Effects of estradiol on dopaminergic synapse formation in the mouse olfactory bulb. J Comp Neurol 2023; 531:528-547. [PMID: 36519231 DOI: 10.1002/cne.25441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 10/24/2022] [Accepted: 11/26/2022] [Indexed: 12/23/2022]
Abstract
Olfactory glomeruli are the sites of initial synaptic integration in olfactory information processing. They are surrounded by juxtaglomerular (JG) cells, which include periglomerular, superficial short axon, and external tufted cells. A subpopulation of JG cells expresses the dopamine synthetic enzymes, tyrosine hydroxylase (TH), and aromatic l-amino acid decarboxylase (AADC). TH cells corelease γ-aminobutyric acid (GABA) and their processes extend to multiple glomeruli forming intra- and interglomerular circuits. It is well established that 17β-estradiol (E2) exerts wide ranging effects in the central nervous system. However, participation of E2 in the modulation of neurotransmission and synaptic plasticity of TH cells in olfactory glomeruli is unknown. To address this, we subcutaneously implanted a 60-day release pellet of E2 or placebo into intact male mice and compared glomerular TH, AADC, and vesicular γ-aminobutyric acid transporter (VGAT) immunoreactivity between them. High-voltage electron microscopy (HVEM) and ultra-HVEM using immunogold revealed significantly increased immunoreactive intensity at the cellular level for TH and AADC after E2 treatment and for VGAT in TH cells. These results indicate that E2 may affect the interplay between dopaminergic and GABAergic systems. Moreover, random-section electron microscopy analysis showed a significant increase in the number of symmetrical synapses from TH cell to mitral/tufted cell dendrites after E2 treatment. This result was supported by quantitative immunofluorescence staining with synapse markers. Together, these data indicate that E2 may regulate inhibition between TH cells and olfactory bulb neurons within the glomerulus via interaction between dopaminergic and GABAergic systems, thereby contributing to neuromodulation of odor information processing.
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Affiliation(s)
- Emi Kiyokage
- Department of Medical Technology, Kawasaki University of Medical Welfare, Kurashiki, Japan
| | - Satoshi Ichikawa
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Ibaraki, Japan
| | - Sawa Horie
- Department of Anatomy, Kawasaki Medical School, Kurashiki, Japan
| | - Shuichi Hayashi
- Department of Anatomy, Kawasaki Medical School, Kurashiki, Japan
| | - Kazunori Toida
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Ibaraki, Japan.,Department of Anatomy, Kawasaki Medical School, Kurashiki, Japan
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Li H, Zhao Y, Shen Q, Li H. Multiple circRNAs regulated by QKI5 conjointly spongemiR-214-3p to antagonize bisphenol A-inducedspermatocyte toxicity. Acta Biochim Biophys Sin (Shanghai) 2022; 54:1090-1099. [PMID: 35959880 PMCID: PMC9827849 DOI: 10.3724/abbs.2022101] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 01/07/2022] [Indexed: 11/25/2022] Open
Abstract
Although circular RNAs (circRNAs) are found to play important roles in many pathophysiological processes, the canonical theory that they act as microRNA sponges is now more and more challenged, given that most circRNAs only have few binding sites in a particular microRNA. Our previous study revealed that some up-regulated circRNAs play protective roles in bisphenol A (BPA)-induced toxicity in GC-2 germ cells. Here by CCK-8 assay, apoptosis assay, qRT-PCR and western blot analysis, we further discover that circRNAs (represented by circDcbld2, circMapk1 and circTbcld20) can cooperatively sponge miR-214-3p and then up-regulate AKT1 in ameliorating BPA-induced reproductive toxicity. They share binding sites with miR-214-3p and collectively reinforce the sponging effects. In addition, the upstream regulation mechanism, proven by bioinformatics analysis and in vitro gain- and loss-of-function study, shows that down-regulation of RNA binding protein QKI5 after BPA exposure can increase the expressions of these protective circRNAs, and thus activate the cell protective process. The QKI5-circDcbld2/circMapk1/circTblcd20-miR-214-3p-AKT1 axis ameliorates the toxic effect of BPA on GC-2 cells. Many other circRNAs up-regulated upon BPA treatment and QKI5 down-regulation also show binding sites with miR-214-3p. Thus the above axis may also be extrapolated to other circRNAs. Our results enrich the context of circRNA sponge mode and may provide new ideas in future multiple nucleic acid therapy.
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Affiliation(s)
- Huimin Li
- Institute of Reproductive Health/Center of Reproductive MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China
- Guilin Medical UniversityGuilin541000China
| | - Yunhan Zhao
- Institute of Reproductive Health/Center of Reproductive MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China
| | - Qiuzi Shen
- Institute of Reproductive Health/Center of Reproductive MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China
| | - Honggang Li
- Institute of Reproductive Health/Center of Reproductive MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China
- Wuhan Tongji Reproductive Medicine HospitalWuhan430030China
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Yang W, Deng J, Gao J, Yang H, Chen Q, Niya Z, Ling X, Zhang G, Zou P, Sun L, Huang L, Liu J, Cao J, Ao L. Associations between isoflavone exposure and reproductive damage in adult males: evidence from human and model system studies. Biol Reprod 2022; 107:1360-1373. [PMID: 35948002 DOI: 10.1093/biolre/ioac157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 03/21/2022] [Accepted: 08/08/2022] [Indexed: 11/14/2022] Open
Abstract
It's controversial whether exposure to isoflavones, constituents of certain plants such as soy bean, exerts male reproductive toxicity. This study was designed to investigate whether isoflavone exposure during adulthood could have deleterious impacts on male reproductive health by the cross-sectional study, animal experiments, and in vitro tests. In the cross-sectional study, we observed that urinary isoflavones were not significantly associated with semen quality including sperm concentrations, sperm count, progressive motility, and total motility, respectively (All P-value for trend>0.05). However, negative associations were found between plasma testosterone and urinary Σisoflavones, genistein, glycitein, and dihydrodaidzein (all P-value for trend <0.05). In the animal experiments, serum and intratesticular testosterone levels were decreased in mice exposed to several dosages of genistein. Genistein administration caused up-regulation of estrogen receptor alpha (ERα) and down-regulation of cytochrome P45017A1 (CYP17A1) protein levels in testes of mice. However, genistein treatment during adulthood did not induce appreciable structural damages of reproductive system in mice. In vitro tests, we observed that genistein of different dosages (0.01, 2.5, 10 μM) caused a concentration dependent inhibition of testosterone production by TM3 Leydig cells (half-maximal inhibitory concentration = 3.796 nM, P < 0.05). Elevated protein expression of ERα and decreased mRNA/protein level of CYP17A1 were also observed in genistein-treated cells. Protein level of CYP17A1 and testosterone concentration were significantly restored in the ERα siRNA-transfected cells, compared to cells that treated with genistein alone (P < 0.05). The results demonstrate that exposure to isoflavones during adulthood may be associated with alterations of reproductive hormones. Particularly for genistein, which inhibits testosterone biosynthesis through up-regulation of ERα in Leydig cells of mice, might induce the disruption of testosterone production in human. The present study provides novel perspective into potential targets for male reproductive compromise induced by isoflavone exposure.
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Affiliation(s)
- Wang Yang
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Jiuyang Deng
- Department of Occupational Health, School of Public Health, Shanxi Medical University, 56 Xinjian South Road, Taiyuan 030001, China
| | - Jianfang Gao
- Tongren Hospital, Shanghai Jiao Tong University School of Medicine, 1111 Xianxia Road, Shanghai 200336, China
| | - Huan Yang
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Qing Chen
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Zhou Niya
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Xi Ling
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Guowei Zhang
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Peng Zou
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Lei Sun
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Linping Huang
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Jinyi Liu
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Jia Cao
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
| | - Lin Ao
- Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Gaotanyan St 30, Chongqing 400038, China
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10
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Navin AK, Aruldhas MM, Navaneethabalakrishnan S, Mani K, Michael FM, Srinivasan N, Banu SK. Prenatal exposure to hexavalent chromium disrupts testicular steroidogenic pathway in peripubertal F 1 rats. Reprod Toxicol 2021; 101:63-73. [PMID: 33675932 DOI: 10.1016/j.reprotox.2021.01.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 01/07/2021] [Accepted: 01/29/2021] [Indexed: 11/21/2022]
Abstract
We have reported sub-fertility in F1 progeny rats with gestational exposure to hexavalent chromium [Cr(VI)], which had disrupted Sertoli cell (SC) structure and function, and decreased testosterone (T). However, the underlying mechanism for reduced T remains to be understood. We tested the hypothesis "transient prenatal exposure to Cr(VI) affects testicular steroidogenesis by altering hormone receptors and steroidogenic enzyme proteins in Leydig cells (LCs)." Pregnant Wistar rats were given drinking water containing 50, 100, and 200 mg/L potassium dichromate during gestational days 9-14, encompassing fetal differentiation window of the testis from the bipotential gonad. F1 male rats were euthanized on postnatal day 60 (peripubertal rats with adult-type LCs alone). Results showed that prenatal exposure to Cr(VI): (i) increased accumulation of Cr(III) in the testis of F1 rats; (ii) increased serum levels of luteinizing and follicle stimulating hormones (LH and FSH), and 17β estradiol, and decreased prolactin and T; (iii) decreased steroidogenic acute regulatory protein, cytochrome P450 11A1, cytochrome P450 17A1, 3β- and 17β-hydroxysteroid dehydrogenases, cytochrome P450 aromatase and 5α reductase proteins, (iv) decreased specific activities of 3β and 17β hydroxysteroid dehydrogenases; (v) decreased receptors of LH, androgen and estrogen in LCs; (vi) decreased 5α reductase and receptor proteins of FSH, androgen, and estrogen in SCs. The current study concludes that prenatal exposure to Cr(VI) disrupts testicular steroidogenesis in F1 progeny by repressing hormone receptors and key proteins of the steroidogenic pathway in LCs and SCs.
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Affiliation(s)
- Ajit Kumar Navin
- Department of Endocrinology, Dr. A.L.M. Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Taramani-Velachery Link Road, Chennai, 600113, Tamil Nadu, India; Department of Veterinary Integrative Biosciences, College of Veterinary Medicine & Biomedical Sciences, TAMU-4458, Texas A&M University, College Station, TX, 77843, USA
| | - Mariajoseph Michael Aruldhas
- Department of Endocrinology, Dr. A.L.M. Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Taramani-Velachery Link Road, Chennai, 600113, Tamil Nadu, India.
| | - Shobana Navaneethabalakrishnan
- Department of Endocrinology, Dr. A.L.M. Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Taramani-Velachery Link Road, Chennai, 600113, Tamil Nadu, India
| | - Kathireshkumar Mani
- Department of Endocrinology, Dr. A.L.M. Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Taramani-Velachery Link Road, Chennai, 600113, Tamil Nadu, India
| | - Felicia Mary Michael
- Department of Anatomy, Dr. A.L.M. Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Taramani-Velachery Link Road, Chennai, 600113, Tamil Nadu, India
| | - Narasimhan Srinivasan
- Department of Tissue Engineering and Regenerative Medicine, Chettinad Academy of Research and Education, Chettinad Health City, Kelambakkam, 603103, Tamil Nadu, India
| | - Sakhila K Banu
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine & Biomedical Sciences, TAMU-4458, Texas A&M University, College Station, TX, 77843, USA
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11
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Smith KB, Murray E, Chandrasegaram R, Liang J, Mallet JF, Matar C, Blaustein JD, Ismail N. Pubertal immune challenge suppresses the hypothalamic-pituitary-gonadal axis in male and female mice. Brain Res Bull 2021; 170:90-97. [PMID: 33571552 DOI: 10.1016/j.brainresbull.2021.02.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 01/24/2021] [Accepted: 02/02/2021] [Indexed: 12/18/2022]
Abstract
Kisspeptin is a neuropeptide responsible for propagating the hypothalamic-pituitary-gonadal (HPG) axis and initiating puberty. Pubertal exposure to an immune challenge causes enduring sexual behavior dysfunction in males and females, but the mechanism underlying this stress-induced sexual dysfunction remains unknown. Previous findings show that stress exposure can downregulate the HPG axis in adult females. However, it is unclear whether stress induced HPG axis suppression is limited to adult females or also extends to males and to pubertal animal models. The current study was designed to investigate the sex-specific consequences of a pubertal immune challenge on specific components of the HPG axis. Six-week old pubertal male and female mice were treated with saline or with lipopolysaccharide, a bacterial endotoxin. Expression of hypothalamic Kiss1 and Kiss1R as well as serum concentrations of luteinizing hormone, follicle-stimulating hormone, and growth hormone were examined. Pubertal lipopolysaccharide treatment decreased hypothalamic Kiss1, but not Kiss1R, expression in both males and females. Furthermore, only males showed decreases in circulating luteinizing and follicle-stimulating hormones. These results show that pubertal immune challenge suppresses the HPG axis by inhibiting Kiss1 production and decreasing serum gonadotropin concentrations in pubertal males, but points to a different mechanism in pubertal females.
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Affiliation(s)
- Kevin B Smith
- NISE Laboratory, School of Psychology, Faculty of Social Science, University of Ottawa, 136 Jean-Jacques Lussier, Ottawa, Ontario, K1N 6N5, Canada.
| | - Emma Murray
- NISE Laboratory, School of Psychology, Faculty of Social Science, University of Ottawa, 136 Jean-Jacques Lussier, Ottawa, Ontario, K1N 6N5, Canada.
| | - Rajini Chandrasegaram
- NISE Laboratory, School of Psychology, Faculty of Social Science, University of Ottawa, 136 Jean-Jacques Lussier, Ottawa, Ontario, K1N 6N5, Canada.
| | - Jacky Liang
- NISE Laboratory, School of Psychology, Faculty of Social Science, University of Ottawa, 136 Jean-Jacques Lussier, Ottawa, Ontario, K1N 6N5, Canada.
| | - Jean-François Mallet
- Faculty of Health Sciences, University of Ottawa, 451 Smyth Rd, Ottawa, Ontario, K1H 8L1, Canada.
| | - Chantal Matar
- Faculty of Health Sciences, University of Ottawa, 451 Smyth Rd, Ottawa, Ontario, K1H 8L1, Canada
| | - Jeffrey D Blaustein
- Center for Neuroendocrine Studies, Department of Psychological and Brain Sciences, University of Massachusetts, 135 Hicks Way, Amherst, MA, 01003, USA.
| | - Nafissa Ismail
- NISE Laboratory, School of Psychology, Faculty of Social Science, University of Ottawa, 136 Jean-Jacques Lussier, Ottawa, Ontario, K1N 6N5, Canada; Brain and Mind Research Institute, University of Ottawa, Ottawa, Ontario, Canada.
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12
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Esparza LA, Terasaka T, Lawson MA, Kauffman AS. Androgen Suppresses In Vivo and In Vitro LH Pulse Secretion and Neural Kiss1 and Tac2 Gene Expression in Female Mice. Endocrinology 2020; 161:5930836. [PMID: 33075809 PMCID: PMC7671291 DOI: 10.1210/endocr/bqaa191] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Indexed: 12/12/2022]
Abstract
Androgens can affect the reproductive axis of both sexes. In healthy women, as in men, elevated exogenous androgens decrease gonad function and lower gonadotropin levels; such circumstances occur with anabolic steroid abuse or in transgender men (genetic XX individuals) taking androgen supplements. The neuroendocrine mechanisms by which endogenous or exogenous androgens regulate gonadotropin release, including aspects of pulsatile luteinizing hormone (LH) secretion, remain unknown. Because animal models are valuable for interrogating neural and pituitary mechanisms, we studied effects of androgens in the normal male physiological range on in vivo LH secretion parameters in female mice and in vitro LH secretion patterns from isolated female pituitaries. We also assessed androgen effects on hypothalamic and gonadotrope gene expression in female mice, which may contribute to altered LH secretion profiles. We used a nonaromatizable androgen, dihydrotestosterone (DHT), to isolate effects occurring specifically via androgen receptor (AR) signaling. Compared with control females, DHT-treated females exhibited markedly reduced in vivo LH pulsatility, with decreases in pulse frequency, amplitude, peak, and basal LH levels. Correlating with reduced LH pulsatility, DHT-treated females also exhibited suppressed arcuate nucleus Kiss1 and Tac2 expression. Separate from these neural effects, we determined in vitro that the female pituitary is directly inhibited by AR signaling, resulting in lower basal LH levels and reduced LH secretory responses to gonadotropin-releasing hormone pulses, along with lower gonadotropin gene expression. Thus, in normal adult females, male levels of androgen acting via AR can strongly inhibit the reproductive axis at both the neural and pituitary levels.
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Affiliation(s)
- Lourdes A Esparza
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California San Diego, La Jolla, California
| | - Tomohiro Terasaka
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California San Diego, La Jolla, California
| | - Mark A Lawson
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California San Diego, La Jolla, California
| | - Alexander S Kauffman
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California San Diego, La Jolla, California
- Correspondence: Dr. Alexander S. Kauffman, Department of Obstetrics, Gynecology and Reproductive Sciences, Leichtag Building, Room 3A-15, University of California, San Diego, 9500 Gilman Drive, #0674, La Jolla, CA 92093, USA. E-mail:
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13
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Zheng Z, Liu M, Meng F, Zhang W, Zhang L. Differential distribution and potential regulatory roles of estrogen receptor 2a and 2b in the pituitary of ricefield eel Monopterus albus. Gen Comp Endocrinol 2020; 298:113554. [PMID: 32687932 DOI: 10.1016/j.ygcen.2020.113554] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 06/24/2020] [Accepted: 07/14/2020] [Indexed: 12/14/2022]
Abstract
Estrogens play important regulatory roles in the pituitary of vertebrates. Two forms of estrogen receptor 2 (Esr2), namely Esr2a and Esr2b, are identified in teleosts, but their differential roles remain to be fully elucidated. In the present study, expression and potential functional roles of Esr2a and Esr2b were characterized in ricefield eels. esr2a and esr2b mRNA were broadly distributed in tissues, with high levels observed in the brain, pituitary, and gonads. In order to examine the cellular localization of Esr2a and Esr2b in the pituitary, specific antisera against ricefield eel Esr2a and Esr2b were generated, respectively. Interestingly, immunohistochemistry and Western blot analysis revealed that Esr2a and Esr2b were differentially distributed in the pituitary, with the former localized to the adenohypophysis while the latter to the neurohypophysis. Dual fluorescent immunostaining showed that immunoreactive Esr2a was present in Gh and Prl cells, but not in Lh and Fsh cells. Estradiol (E2) stimulated lhb and prl gene expression in dispersed pituitary cells of intersexual ricefield eels, but had no effects on gh, fshb, and gnrhr2 gene expression and Gh release. Results of the present study are helpful for further understanding the roles and mechanisms of estrogen signals in the pituitary.
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Affiliation(s)
- Zhiqiang Zheng
- Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, PR China
| | - Minqi Liu
- Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, PR China
| | - Feiyan Meng
- Biology Department, School of Life Sciences, Sun Yat-Sen University, Guangzhou, PR China
| | - Weimin Zhang
- Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, PR China; Biology Department, School of Life Sciences, Sun Yat-Sen University, Guangzhou, PR China.
| | - Lihong Zhang
- Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, PR China; Biology Department, School of Life Sciences, Sun Yat-Sen University, Guangzhou, PR China.
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14
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Adegoke EO, Rahman MS, Pang MG. Bisphenols Threaten Male Reproductive Health via Testicular Cells. Front Endocrinol (Lausanne) 2020; 11:624. [PMID: 33042007 PMCID: PMC7518410 DOI: 10.3389/fendo.2020.00624] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 07/30/2020] [Indexed: 12/14/2022] Open
Abstract
Male reproductive function and health are largely dependent on the testes, which are strictly regulated by their major cell components, i. e., Sertoli, Leydig, and germ cells. Sertoli cells perform a crucial phagocytic function in addition to supporting the development of germ cells. Leydig cells produce hormones essential for male reproductive function, and germ cell quality is a key parameter for male fertility assessment. However, these cells have been identified as primary targets of endocrine disruptors, including bisphenols. Bisphenols are a category of man-made organic chemicals used to manufacture plastics, epoxy resins, and personal care products such as lipsticks, face makeup, and nail lacquers. Despite long-term uncertainty regarding their safety, bisphenols are still being used worldwide, especially bisphenol A. While considerable attention has been paid to the effects of bisphenols on health, current bisphenol-related reproductive health cases indicate that greater attention should be given to these chemicals. Bisphenols, especially bisphenol A, F, and S, have been reported to elicit various effects on testicular cells, including apoptosis, DNA damage, disruption of intercommunication among cells, mitochondrial damage, disruption of tight junctions, and arrest of proliferation, which threaten male reproductive health. In addition, bisphenols are xenoestrogens, which alter organs and cells functions via agonistic or antagonistic interplay with hormone receptors. In this review, we provide in utero, in vivo, and in vitro evidence that currently available brands of bisphenols impair male reproductive health through their action on testicular cells.
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Affiliation(s)
| | | | - Myung-Geol Pang
- Department of Animal Science and Technology and BET Research Institute, Chung-Ang University, Anseong, South Korea
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15
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Cara AL, Myers MG, Elias CF. Lack of AR in LepRb Cells Disrupts Ambulatory Activity and Neuroendocrine Axes in a Sex-Specific Manner in Mice. Endocrinology 2020; 161:bqaa110. [PMID: 32609838 PMCID: PMC7383963 DOI: 10.1210/endocr/bqaa110] [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: 02/26/2020] [Accepted: 06/26/2020] [Indexed: 11/19/2022]
Abstract
Disorders of androgen imbalance, such as hyperandrogenism in females or hypoandrogenism in males, increase risk of visceral adiposity, type 2 diabetes, and infertility. Androgens act upon androgen receptors (AR) which are expressed in many tissues. In the brain, AR are abundant in hypothalamic nuclei involved in regulation of reproduction and energy homeostasis, yet the role of androgens acting via AR in specific neuronal populations has not been fully elucidated. Leptin receptor (LepRb)-expressing neurons coexpress AR predominantly in hypothalamic arcuate and ventral premammillary nuclei (ARH and PMv, respectively), with low colocalization in other LepRb neuronal populations, and very low colocalization in the pituitary gland and gonads. Deletion of AR from LepRb-expressing cells (LepRbΔAR) has no effect on body weight, energy expenditure, and glucose homeostasis in male and female mice. However, LepRbΔAR female mice show increased body length later in life, whereas male LepRbΔAR mice show an increase in spontaneous ambulatory activity. LepRbΔAR mice display typical pubertal timing, estrous cycles, and fertility, but increased testosterone levels in males. Removal of sex steroid negative feedback action induced an exaggerated rise in luteinizing hormone in LepRbΔAR males and follicle-stimulating hormone in LepRbΔAR females. Our findings show that AR can directly affect a subset of ARH and PMv neurons in a sex-specific manner and demonstrate specific androgenic actions in the neuroendocrine hypothalamus.
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Affiliation(s)
- Alexandra L Cara
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| | - Martin G Myers
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
- Department of Obstetrics and Gynaecology, University of Michigan, Ann Arbor, Michigan
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16
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Wang L, Moenter SM. Differential Roles of Hypothalamic AVPV and Arcuate Kisspeptin Neurons in Estradiol Feedback Regulation of Female Reproduction. Neuroendocrinology 2020; 110:172-184. [PMID: 31466075 PMCID: PMC7047625 DOI: 10.1159/000503006] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 08/28/2019] [Indexed: 11/19/2022]
Abstract
Mammalian reproductive function includes puberty onset and completion, reproductive cyclicity, steroidogenesis, gametogenesis, fertilization, pregnancy, and lactation; all are indispensable to perpetuate species. Reproductive cycles are critical for providing the hormonal milieu needed for follicular development and maturation of eggs, but cycles, in and of themselves, do not guarantee ovulation will occur. Here, we review the roles in female reproductive neuroendocrine function of two hypothalamic populations that produce the neuropeptide kisspeptin, demonstrating distinct roles in maintaining cycles and ovulation.
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Affiliation(s)
- Luhong Wang
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Suzanne M Moenter
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA,
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA,
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan, USA,
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17
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Davis TL. Nonclassical actions of estradiol-17beta are not detectable in the alphaT3-1 and LbetaT2 immortalized gonadotrope cell lines†. Biol Reprod 2019; 101:791-799. [PMID: 31290547 DOI: 10.1093/biolre/ioz118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 06/24/2019] [Accepted: 07/05/2019] [Indexed: 11/13/2022] Open
Abstract
The immortalized mouse gonadotrope cell lines alphaT3-1 and LbetaT2 cells have been a substitute model for primary gonadotropes. These cell lines have provided a homogeneous cell population, as compared to the dissociated anterior pituitaries, which contain a heterogeneous population of cells potentially responsive to estradiol-17beta (E2). Nonclassical actions of E2 assumed to occur through the plasma membrane estrogen receptor 1 (ESR1, also known as ERalpha). These actions have included inhibition of gonadotropin-releasing hormone (GnRH)-induced increases in intracellular calcium concentrations and phosphorylation of p44/42 mitogen-activated protein kinase (ERK-1/2) in ovine pituitaries including primary gonadotropes in vitro. The objective of the present experiment was to determine if alphaT3-1 and LbetaT2 are cell models with limitations to examine the nonclassical actions of E2 occurring in gonadotropes. Experiments were conducted to determine if the cells have ESR1 at the plasma membrane using biotinylation cell and isolation of surface protein and staining with a fluorescently labeled E2 conjugate. The alphaT3-1 cells contain ESR1 associated with but not enriched within lipid rafts of the plasma membrane and do not translocate to lipid rafts upon binding of E2. In contrast, LbetaT2 cells lack ESR1 associated with the plasma membrane. Pretreatment with E2 did not cause inhibition of GnRH-stimulated increases in intracellular concentrations of calcium for either cell type. Phosphorylation of ERK-1/2 was not stimulated by E2 in either cell type. Although these cells lines have been used extensively to study GnRH signaling, in vitro or in vivo effects of nonclassical actions of E2 cannot be replicated in either cell line.
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Affiliation(s)
- Tracy L Davis
- Department of Biology, Wingate University, Wingate, North Carolina, USA
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18
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Templin JS, Wyrosdic JC, David CD, Wyrosdic BN, Lapp HE, Bala A, Bartlett A, Khan Z, Rokicki A, Park JH. Peripubertal gonadal steroids are necessary for steroid-independent male sexual behavior in castrated B6D2F1 male mice. Horm Behav 2019; 113:38-46. [PMID: 31047887 DOI: 10.1016/j.yhbeh.2019.04.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 04/14/2019] [Accepted: 04/27/2019] [Indexed: 11/23/2022]
Abstract
Gonadal steroids play an integral role in male sexual behavior, and in most rodent models, this relationship is tightly coupled. However, many other species, including humans, continue to demonstrate male sex behavior in the absence of gonadal steroids, and the mechanisms that regulate steroid-independent male sex behavior are not well understood. Approximately 30% of castrated male B6D2F1 hybrid mice display male sex behavior many months after castration, allowing for the investigation of individual variation in steroidal regulation of male sex behavior. During both the perinatal and peripubertal periods of development, the organizational effects of gonadal steroids on sexual differentiation of the neural circuits controlling male sex behavior are well-documented. Several factors can alter the normal range of gonadal steroids or their receptors which may lead to the disruption of the normal processes of masculinization and defeminization. It is unknown whether the organizational effects of gonadal hormones during puberty are necessary for steroid-independent male sex behavior. However, gonadal steroids during puberty were not necessary for either testosterone or estradiol to activate male sex behavior in adulthood. Furthermore, activation of male sex behavior was initiated sooner in hybrid male mice castrated prior to puberty that were administered estradiol in adulthood compared to those that were provided testosterone. The underlying mechanisms by which gonadal hormones, during both the perinatal and peripubertal developmental periods of sexual differentiation, organize the normal maturation of neural circuitry that regulates steroid-independent male sex behavior in adult castrated B6D2F1 male mice warrants further investigation.
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Affiliation(s)
- Jay Scott Templin
- Psychology Department, University of Massachusetts Boston, Boston, MA 02125, United States of America.
| | - Joshua C Wyrosdic
- Psychology Department, University of Massachusetts Boston, Boston, MA 02125, United States of America; Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre, 1650 Cedar Avenue, Montreal H3G 1A4, Canada
| | - Caroline D David
- Psychology Department, University of Massachusetts Boston, Boston, MA 02125, United States of America
| | - Brianna N Wyrosdic
- Psychology Department, University of Massachusetts Boston, Boston, MA 02125, United States of America
| | - Hannah E Lapp
- Psychology Department, University of Massachusetts Boston, Boston, MA 02125, United States of America
| | - Andis Bala
- Psychology Department, University of Massachusetts Boston, Boston, MA 02125, United States of America
| | - Alexander Bartlett
- Psychology Department, University of Massachusetts Boston, Boston, MA 02125, United States of America
| | - Zara Khan
- Psychology Department, University of Massachusetts Boston, Boston, MA 02125, United States of America
| | - Alicia Rokicki
- Psychology Department, University of Massachusetts Boston, Boston, MA 02125, United States of America
| | - Jin Ho Park
- Psychology Department, University of Massachusetts Boston, Boston, MA 02125, United States of America
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19
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Cariati F, D'Uonno N, Borrillo F, Iervolino S, Galdiero G, Tomaiuolo R. "Bisphenol a: an emerging threat to male fertility". Reprod Biol Endocrinol 2019; 17:6. [PMID: 30660193 PMCID: PMC6339693 DOI: 10.1186/s12958-018-0447-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/17/2018] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Among the factors causing male infertility, one of the most debated is the exposure to environmental contaminants. Recently, the chemical compound Bisphenol A (BPA) has drawn attention from the reproductive science community, due to its ubiquitous presence in day-to-day life. Its toxic action appears to mainly affect the male reproductive system, directly impacting male fertility. MAIN: The purpose of this review is to investigate current research data on BPA, providing an overview of the findings obtained from studies in animal and human models, as well as on its supposed mechanisms of action. CONCLUSION A clear understanding of BPA action mechanisms, as well as the presumed risks deriving from its exposure, is becoming crucial to preserve male fertility. The development and validation of methodologies to detect BPA toxic effects on reproductive organs can provide greater awareness of the potential threat that this chemical represents.
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Affiliation(s)
- Federica Cariati
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Via Sergio Pansini, 5 -, 80131, Naples, Italy.
- CEINGE-Biotecnologie Avanzate s.c.a r.l., Naples, Italy.
- KronosDNA s.r.l., Spin-off Università degli Studi di Napoli Federico II, Naples, Italy.
| | - Nadja D'Uonno
- CEINGE-Biotecnologie Avanzate s.c.a r.l., Naples, Italy
| | - Francesca Borrillo
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Via Sergio Pansini, 5 -, 80131, Naples, Italy
- CEINGE-Biotecnologie Avanzate s.c.a r.l., Naples, Italy
| | - Stefania Iervolino
- KronosDNA s.r.l., Spin-off Università degli Studi di Napoli Federico II, Naples, Italy
| | - Giacomo Galdiero
- Dipartimento di Medicina Clinica e Chirurgia, Università degli Studi di Napoli Federico II, Naples, Italy
| | - Rossella Tomaiuolo
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Via Sergio Pansini, 5 -, 80131, Naples, Italy
- CEINGE-Biotecnologie Avanzate s.c.a r.l., Naples, Italy
- KronosDNA s.r.l., Spin-off Università degli Studi di Napoli Federico II, Naples, Italy
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Ogrizek M, Grgurevič N, Snoj T, Majdič G. Injections to pregnant mice produce prenatal stress that affects aggressive behavior in their adult male offspring. Horm Behav 2018; 106:35-43. [PMID: 30201533 DOI: 10.1016/j.yhbeh.2018.09.001] [Citation(s) in RCA: 4] [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: 03/23/2018] [Revised: 09/04/2018] [Accepted: 09/06/2018] [Indexed: 12/11/2022]
Abstract
Maternal stress could reprogram the developing fetal nervous system. A common target of maternal glucocorticoids is fetal neuro-endocrine axis. In the present study, pregnant mice were exposed to stress by injection and their male offspring were tested for sexual and aggressive behaviors in adult life. Three groups of pregnant mice were exposed to stress by sham syringe injection. The first group was injected on days 13, 14, and 15 p.c., the second group was injected on days 17 and 18 p.c., and the third group was injected daily from days 13 to 18 p.c. while control mice were not injected. Male offspring that were exposed to stress on days 13-18 p.c. and 17-18 p.c. were less aggressive and had lower blood testosterone levels in comparison to the control group. In male sexual behavior, there were no statistically significant differences between the groups. Body weight differed significantly with groups injected on days 13-18 p.c. and 13-15 p.c. having significantly higher body weight in adult life than the other two groups. After behavioral testing, brains were processed for immunohistochemical staining with antibodies against vasopressin (AVP) and calbindin (CALB). The expression of AVP and CALB in the lateral septum and in the preoptic area, respectively, did not differ between groups, suggesting that these two masculinization markers were not affected by prenatal stress. Present study therefore shows that even presumably mild and short prenatal stress weakens aggressive behavior of adult male mice, possibly due to reduced testosterone levels in blood.
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Affiliation(s)
- Monika Ogrizek
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia
| | - Neža Grgurevič
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia
| | - Tomaž Snoj
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia
| | - Gregor Majdič
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia; Institute of Physiology, Medical School, University of Maribor, Maribor, Slovenia.
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Pyun BJ, Yang H, Sohn E, Yu SY, Lee D, Jung DH, Ko BS, Lee HW. Tetragonia tetragonioides (Pall.) Kuntze Regulates Androgen Production in a Letrozole-Induced Polycystic Ovary Syndrome Model. Molecules 2018; 23:molecules23051173. [PMID: 29757997 PMCID: PMC6099488 DOI: 10.3390/molecules23051173] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 05/04/2018] [Accepted: 05/11/2018] [Indexed: 11/16/2022] Open
Abstract
Tetragonia tetragonioides (Pall.) Kuntze (TTK) is a medicinal plant traditionally used to treat various diseases such as diabetic, inflammatory, and female-related disorders. Polycystic ovary syndrome (PCOS) is a common endocrinological disorder in women of reproductive age, and hyperandrogenism is a prominent feature of PCOS resulting in anovulation and infertility. In this study, we investigated the effects of a TTK extract on androgen generation and regulation of steroidogenic enzymes in vitro and in vivo. Human adrenocortical NCI-H295R cells were used to assess the effects of TTK extract on production of dehydroepiandrosterone and testosterone, as well as the protein expression of steroidogenic enzymes. Further, a letrozole-induced PCOS rat model was used in vivo to assess whether dietary administration of TTK extract restores normal hormones and reduces PCOS symptoms. TTK extract significantly inhibited forskolin (FOR)-induced androgen production in NCI-H295R cells and serum luteinizing hormone, testosterone, and follicular cysts, but not estradiol, were reduced in letrozole-induced PCOS rats orally administered the TTK extract. In addition, TTK extract inhibits androgen biosynthesis through the ERK-CREB signaling pathway, which regulates CYP17A1 or HSD3B2 expression. TTK extract could be utilized for the prevention and treatment of hyperandrogenism and other types of PCOS.
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Affiliation(s)
- Bo-Jeong Pyun
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Korea.
| | - Hyun Yang
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Korea.
| | - Eunjin Sohn
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Korea.
| | - Song Yi Yu
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Korea.
| | - Dongoh Lee
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Korea.
| | - Dong Ho Jung
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Korea.
| | - Byoung Seob Ko
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Korea.
| | - Hye Won Lee
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Korea.
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Mhaouty-Kodja S. Role of the androgen receptor in the central nervous system. Mol Cell Endocrinol 2018; 465:103-112. [PMID: 28826929 DOI: 10.1016/j.mce.2017.08.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 07/30/2017] [Accepted: 08/02/2017] [Indexed: 11/17/2022]
Abstract
The involvement of gonadal androgens in functions of the central nervous system was suggested for the first time about half a century ago. Since then, the number of functions attributed to androgens has steadily increased, ranging from regulation of the hypothalamic-pituitary-gonadal axis and reproductive behaviors to modulation of cognition, anxiety and other non-reproductive functions. This review focuses on the implication of the neural androgen receptor in these androgen-sensitive functions and behaviors.
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Affiliation(s)
- Sakina Mhaouty-Kodja
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Neuroscience Paris Seine - Institut de Biologie Paris Seine, 7 Quai St Bernard, 75005 Paris, France.
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23
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Büdefeld T, Spanic T, Vrecl M, Majdic G. Fezf1 is a novel regulator of female sex behavior in mice. Horm Behav 2018; 97:94-101. [PMID: 29080672 DOI: 10.1016/j.yhbeh.2017.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 09/26/2017] [Accepted: 10/24/2017] [Indexed: 11/24/2022]
Abstract
UNLABELLED Female sexual behavior is a complex process regulated by multiple brain circuits and influenced by sex steroid hormones acting in the brain. Several regions in the hypothalamus have been implicated in the regulation of female sexual behavior although a complete circuitry involved in female sexual behavior is not understood. Fez family zinc finger 1 (Fezf1) gene is a brain specific gene that has been mostly studied in the context of olfactory development, although in a recent study, FEZF1 has been identified as one of the genes responsible for the development of Kallman syndrome. In the present study, we utilized shRNA approach to downregulate Fezf1 in the ventromedial nucleus of the hypothalamus (VMN) with the aim to explore the role of this gene. Adult female mice were stereotaxically injected with lentiviral vectors encoding shRNA against Fezf1 gene. Mice injected with shRNA against Fezf1 had significantly reduced female sexual behavior, presumably due to the downregulation of estrogen receptor alpha (ERα), as the number of ERα-immunoreactive cells in the VMN of Fezf1 mice was significantly lower in comparison to controls. However, no effect on body weight or physical activity was observed in mice with downregulated Fezf1, suggesting that the role of Fezf1 in the VMN is limited to the regulation of sexual behavior. SIGNIFICANCE STATEMENT Fezf1 gene has been identified in the present study as a regulator of female sexual behavior in mice. Regulation of the female sexual behavior could be through the regulation of estrogen receptor alpha expression in the ventromedial nucleus of the hypothalamus, as the expression of this receptor was reduced in mice with downregulated Fezf1. As expression of Fezf1 is very specific in the brain, this gene could present a potential target for the development of novel drugs regulating hypoactive sexual desire disorder in women, if similar function of FEZF1 will be confirmed in humans.
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Affiliation(s)
- Tomaz Büdefeld
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia
| | - Tanja Spanic
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia
| | - Milka Vrecl
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia
| | - Gregor Majdic
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia; Institute of Physiology, Medical School, University of Maribor, Maribor, Slovenia.
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24
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Davey RA, Clarke MV, Russell PK, Rana K, Seto J, Roeszler KN, How JMY, Chia LY, North K, Zajac JD. Androgen Action via the Androgen Receptor in Neurons Within the Brain Positively Regulates Muscle Mass in Male Mice. Endocrinology 2017; 158:3684-3695. [PMID: 28977603 DOI: 10.1210/en.2017-00470] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 07/25/2017] [Indexed: 11/19/2022]
Abstract
Although it is well established that exogenous androgens have anabolic effects on skeletal muscle mass in humans and mice, data from muscle-specific androgen receptor (AR) knockout (ARKO) mice indicate that myocytic expression of the AR is dispensable for hind-limb muscle mass accrual in males. To identify possible indirect actions of androgens via the AR in neurons to regulate muscle, we generated neuron-ARKO mice in which the dominant DNA binding-dependent actions of the AR are deleted in neurons of the cortex, forebrain, hypothalamus, and olfactory bulb. Serum testosterone and luteinizing hormone levels were elevated twofold in neuron-ARKO males compared with wild-type littermates due to disruption of negative feedback to the hypothalamic-pituitary-gonadal axis. Despite this increase in serum testosterone levels, which was expected to increase muscle mass, the mass of the mixed-fiber gastrocnemius (Gast) and the fast-twitch fiber extensor digitorum longus hind-limb muscles was decreased by 10% in neuron-ARKOs at 12 weeks of age, whereas muscle strength and fatigue of the Gast were unaffected. The mass of the soleus muscle, however, which consists of a high proportion of slow-twitch fibers, was unaffected in neuron-ARKOs, demonstrating a stimulatory action of androgens via the AR in neurons to increase the mass of fast-twitch hind-limb muscles. Furthermore, neuron-ARKOs displayed reductions in voluntary and involuntary physical activity by up to 60%. These data provide evidence for a role of androgens via the AR in neurons to positively regulate fast-twitch hind-limb muscle mass and physical activity in male mice.
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Affiliation(s)
- Rachel A Davey
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia
| | - Michele V Clarke
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia
| | - Patricia K Russell
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia
| | - Kesha Rana
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia
| | - Jane Seto
- Murdoch Children's Research Institute, Parkville 3052, Victoria, Australia
| | - Kelly N Roeszler
- Murdoch Children's Research Institute, Parkville 3052, Victoria, Australia
| | - Jackie M Y How
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia
| | - Ling Yeong Chia
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia
| | - Kathryn North
- Murdoch Children's Research Institute, Parkville 3052, Victoria, Australia
| | - Jeffrey D Zajac
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia
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25
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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.
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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.
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26
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Jacob DA, Temple JL, Patisaul HB, Young LJ, Rissman EF. Coumestrol Antagonizes Neuroendocrine Actions of Estrogen via the Estrogen Receptor α. Exp Biol Med (Maywood) 2016; 226:301-6. [PMID: 11368421 DOI: 10.1177/153537020122600406] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The phytoestrogen coumestrol has estrogenic actions on peripheral reproductive tissues. Yet in the brain this compound has both estrogenic and anti-estrogenic effects. We used estrogen receptor α knockout mice (ERαKO) to determine whether coumestrol has estrogenic actions in mice and also if these effects are mediated by the classic ERα. Female wild-type (WT) and ERαKO mice were ovariectomized and treated with estradiol (E2), dietary coumestrol, both, or neither compound. Ten days later the animals were sacrificed, blood was collected, and brain tissues were perfused. Fixed brains were sectioned and immunocytochemistry was employed to quantify progesterone receptors (PR) in the medial preoptic (POA) and ventromedial nucleus of the hypothalamus (VMN). Plasma was assayed for luteinizing hormone (LH). Estrogen treatment induced PR immunoreactivity in both regions in brains of WT females. In ERαKO mice, lower levels of PR were induced. The stimulatory effects of E2 on PR were attenuated in the POA by cotreatment with coumestrol, and the same trend was noted in the VMN. WT ovariectomized females treated with E2 had low levels of LH, while LH was high in untreated females and even higher in ovariectomized females treated with coumestrol. ERαKO females in all treatment groups had high levels of LH. Taken together, the results show that coumestrol has anti-estrogenic actions in the brain and pituitary and that ERα mediates these effects.
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Affiliation(s)
- D A Jacob
- Department of Biology and Neuroscience Program, University of Virginia, Charlottesville 22904-4328, USA
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27
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Bálint F, Liposits Z, Farkas I. Estrogen Receptor Beta and 2-arachidonoylglycerol Mediate the Suppressive Effects of Estradiol on Frequency of Postsynaptic Currents in Gonadotropin-Releasing Hormone Neurons of Metestrous Mice: An Acute Slice Electrophysiological Study. Front Cell Neurosci 2016; 10:77. [PMID: 27065803 PMCID: PMC4809870 DOI: 10.3389/fncel.2016.00077] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 03/11/2016] [Indexed: 11/25/2022] Open
Abstract
Gonadotropin-releasing hormone (GnRH) neurons are controlled by 17β-estradiol (E2) contributing to the steroid feedback regulation of the reproductive axis. In rodents, E2 exerts a negative feedback effect upon GnRH neurons throughout the estrus-diestrus phase of the ovarian cycle. The present study was undertaken to reveal the role of estrogen receptor subtypes in the mediation of the E2 signal and elucidate the downstream molecular machinery of suppression. The effect of E2 administration at low physiological concentration (10 pM) on GnRH neurons in acute brain slices obtained from metestrous GnRH-green fluorescent protein (GFP) mice was studied under paradigms of blocking or activating estrogen receptor subtypes and interfering with retrograde 2-arachidonoylglycerol (2-AG) signaling. Whole-cell patch clamp recordings revealed that E2 significantly diminished the frequency of spontaneous postsynaptic currents (sPSCs) in GnRH neurons (49.62 ± 7.6%) which effect was abolished by application of the estrogen receptor (ER) α/β blocker Faslodex (1 μM). Pretreatment of the brain slices with cannabinoid receptor type 1 (CB1) inverse agonist AM251 (1 μM) and intracellularly applied endocannabinoid synthesis blocker THL (10 μM) significantly attenuated the effect of E2 on the sPSCs. E2 remained effective in the presence of tetrodotoxin (TTX) indicating a direct action of E2 on GnRH cells. The ERβ specific agonist DPN (10 pM) also significantly decreased the frequency of miniature postsynaptic currents (mPSCs) in GnRH neurons. In addition, the suppressive effect of E2 was completely blocked by the selective ERβ antagonist PHTPP (1 μM) indicating that ERβ is required for the observed rapid effect of the E2. In contrast, the ERα agonist PPT (10 pM) or the membrane-associated G protein-coupled estrogen receptor (GPR30) agonist G1 (10 pM) had no significant effect on the frequency of mPSCs in these neurons. AM251 and tetrahydrolipstatin (THL) significantly abolished the effect of E2 whereas AM251 eliminated the action of DPN on the mPSCs. These data suggest the involvement of the retrograde endocannabinoid mechanism in the rapid direct effect of E2. These results collectively indicate that estrogen receptor beta and 2-AG/CB1 signaling mechanisms are coupled and play an important role in the mediation of the negative estradiol feedback on GnRH neurons in acute slice preparation obtained from intact, metestrous mice.
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Affiliation(s)
- Flóra Bálint
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of SciencesBudapest, Hungary; Roska Tamás Doctoral School of Sciences and Technology, Faculty of Information Technology and Bionics, Pázmány Péter Catholic UniversityBudapest, 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
| | - Imre Farkas
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences Budapest, Hungary
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28
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Swift-Gallant A, Coome LA, Ramzan F, Monks DA. Nonneural Androgen Receptors Affect Sexual Differentiation of Brain and Behavior. Endocrinology 2016; 157:788-98. [PMID: 26636184 DOI: 10.1210/en.2015-1355] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Testosterone, acting via estrogenic and androgenic pathways, is the major endocrine mechanism promoting sexual differentiation of the mammalian nervous system and behavior, but we have an incomplete knowledge of which cells and tissues mediate these effects. To distinguish between neural and nonneural actions of androgens in sexual differentiation of brain and behavior, we generated a loxP-based transgenic mouse, which overexpresses androgen receptors (ARs) when activated by Cre. We used this transgene to overexpress AR globally in all tissues using a cytomegalovirus (CMV)-Cre driver (CMV-AR), and we used a Nestin-Cre driver to overexpress AR only in neural tissue (Nes-AR). We then examined whether neural or global AR overexpression can affect socio-sexual behaviors using a resident-intruder paradigm. We found that both neural and global AR overexpression resulted in decreased aggressive behaviors and increased thrusting during mounting of intruders, consistent with a neural site of action. Global, but not neural, AR overexpression in males led to an increase in same-sex anogenital investigation. Together, these results suggest novel roles for nonneural AR in sexual differentiation of mice, and indicate that excess AR can lead to a paradoxical reduction of male-typical behavior.
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Affiliation(s)
- Ashlyn Swift-Gallant
- Departments of Psychology (A.S.-G., L.A.C., F.R., D.A.M.), Neuroscience (L.A.C., F.R., D.A.M.), and Cells and Systems Biology (D.A.M.), University of Toronto, Toronto, Ontario, Canada M5S 3G3; and Department of Psychology (A.S.-G., L.A.C., F.R., D.A.M.), University of Toronto, Mississauga, Mississauga, Ontario, Canada L5L 1C6
| | - Lindsay A Coome
- Departments of Psychology (A.S.-G., L.A.C., F.R., D.A.M.), Neuroscience (L.A.C., F.R., D.A.M.), and Cells and Systems Biology (D.A.M.), University of Toronto, Toronto, Ontario, Canada M5S 3G3; and Department of Psychology (A.S.-G., L.A.C., F.R., D.A.M.), University of Toronto, Mississauga, Mississauga, Ontario, Canada L5L 1C6
| | - Firyal Ramzan
- Departments of Psychology (A.S.-G., L.A.C., F.R., D.A.M.), Neuroscience (L.A.C., F.R., D.A.M.), and Cells and Systems Biology (D.A.M.), University of Toronto, Toronto, Ontario, Canada M5S 3G3; and Department of Psychology (A.S.-G., L.A.C., F.R., D.A.M.), University of Toronto, Mississauga, Mississauga, Ontario, Canada L5L 1C6
| | - D Ashley Monks
- Departments of Psychology (A.S.-G., L.A.C., F.R., D.A.M.), Neuroscience (L.A.C., F.R., D.A.M.), and Cells and Systems Biology (D.A.M.), University of Toronto, Toronto, Ontario, Canada M5S 3G3; and Department of Psychology (A.S.-G., L.A.C., F.R., D.A.M.), University of Toronto, Mississauga, Mississauga, Ontario, Canada L5L 1C6
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29
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O’Hara L, Curley M, Tedim Ferreira M, Cruickshanks L, Milne L, Smith LB. Pituitary androgen receptor signalling regulates prolactin but not gonadotrophins in the male mouse. PLoS One 2015; 10:e0121657. [PMID: 25799562 PMCID: PMC4370825 DOI: 10.1371/journal.pone.0121657] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Accepted: 02/11/2015] [Indexed: 12/02/2022] Open
Abstract
Production of the androgen testosterone is controlled by a negative feedback loop within the hypothalamic-pituitary-gonadal (HPG) axis. Stimulation of testicular Leydig cells by pituitary luteinising hormone (LH) is under the control of hypothalamic gonadotrophin releasing hormone (GnRH), while suppression of LH secretion by the pituitary is controlled by circulating testosterone. Exactly how androgens exert their feedback control of gonadotrophin secretion (and whether this is at the level of the pituitary), as well as the role of AR in other pituitary cell types remains unclear. To investigate these questions, we exploited a transgenic mouse line (Foxg1Cre/+; ARfl/y) which lacks androgen receptor in the pituitary gland. Both circulating testosterone and gonadotrophins are unchanged in adulthood, demonstrating that AR signalling is dispensable in the male mouse pituitary for testosterone-dependent regulation of LH secretion. In contrast, Foxg1Cre/+; ARfl/y males have a significant increase in circulating prolactin, suggesting that, rather than controlling gonadotrophins, AR-signalling in the pituitary acts to suppress aberrant prolactin production in males.
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Affiliation(s)
- Laura O’Hara
- Medical Research Council Centre for Reproductive Health, University of Edinburgh, Edinburgh, United Kingdom
| | - Michael Curley
- Medical Research Council Centre for Reproductive Health, University of Edinburgh, Edinburgh, United Kingdom
| | - Maria Tedim Ferreira
- Medical Research Council Centre for Reproductive Health, University of Edinburgh, Edinburgh, United Kingdom
| | - Lyndsey Cruickshanks
- Medical Research Council Centre for Reproductive Health, University of Edinburgh, Edinburgh, United Kingdom
| | - Laura Milne
- Medical Research Council Centre for Reproductive Health, University of Edinburgh, Edinburgh, United Kingdom
| | - Lee B. Smith
- Medical Research Council Centre for Reproductive Health, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail:
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30
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Kercmar J, Tobet SA, Majdic G. Social isolation during puberty affects female sexual behavior in mice. Front Behav Neurosci 2014; 8:337. [PMID: 25324747 PMCID: PMC4179611 DOI: 10.3389/fnbeh.2014.00337] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 09/08/2014] [Indexed: 11/13/2022] Open
Abstract
Exposure to stress during puberty can lead to long-term behavioral alterations in adult rodents coincident with sex steroid hormone-dependent brain remodeling and reorganization. Social isolation is a stress for social animals like mice, but little is known about the effects of such stress during adolescence on later reproductive behaviors. The present study examined sexual behavior of ovariectomized, estradiol and progesterone primed female mice that were individually housed from 25 days of age until testing at approximately 95 days, or individually housed from day 25 until day 60 (during puberty), followed by housing in social groups. Mice in these isolated groups were compared to females that were group housed throughout the experiment. Receptive sexual behaviors of females and behaviors of stimulus males were recorded. Females housed in social groups displayed greater levels of receptive behaviors in comparison to both socially isolated groups. Namely, social females had higher lordosis quotients (LQs) and more often displayed stronger lordosis postures in comparison to isolated females. No differences between female groups were observed in stimulus male sexual behavior suggesting that female "attractiveness" was not affected by their social isolation. Females housed in social groups had fewer cells containing immunoreactive estrogen receptor (ER) α in the anteroventral periventricular nucleus (AVPV) and in the ventromedial nucleus of the hypothalamus (VMH) than both isolated groups. These results suggest that isolation during adolescence affects female sexual behavior and re-socialization for 1 month in adulthood is insufficient to rescue lordosis behavior from the effects of social isolation during the pubertal period.
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Affiliation(s)
- Jasmina Kercmar
- Veterinary Faculty, Center for Animal Genomics, University of Ljubljana Ljubljana, Slovenia
| | - Stuart A Tobet
- Department of Biomedical Sciences, Colorado State University Fort Collins, CO, USA
| | - Gregor Majdic
- Veterinary Faculty, Center for Animal Genomics, University of Ljubljana Ljubljana, Slovenia ; Institute of Physiology, Medical School, University of Maribor Maribor, Slovenia
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31
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Kercmar J, Snoj T, Tobet SA, Majdic G. Gonadectomy prior to puberty decreases normal parental behavior in adult mice. Horm Behav 2014; 66:667-73. [PMID: 25245159 PMCID: PMC4252646 DOI: 10.1016/j.yhbeh.2014.09.007] [Citation(s) in RCA: 11] [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: 02/14/2014] [Revised: 09/09/2014] [Accepted: 09/11/2014] [Indexed: 01/29/2023]
Abstract
Sex steroid hormones secreted by gonads influence development and expression of many behaviors including parental behaviors. The capacity to display many behaviors develops under the influence of sex steroid hormones; it begins with gonadal differentiation and lasts through puberty. The timing of gonadectomy may have important and long lasting effects on the organization and activation of neural circuits regulating the expression of different behaviors. The present study investigated the importance of exposure to endogenous gonadal steroid hormones during pubertal period/adolescence on parental behavior in adult mice. Male and female WT mice were gonadectomized either before puberty (25 days of age) or after puberty (60 days of age) and tested for parental behavior with and without estradiol benzoate (EB) replacement in adulthood. Additional groups of mice were gonadectomized at P25 and supplemented with estradiol (females) or testosterone (males) during puberty. Female mice gonadectomized after puberty or gonadectomized before puberty and supplemented with estradiol during puberty, displayed better pup directed parental behaviors in comparison to mice gonadectomized at 25 days of age regardless of treatment with estradiol in adulthood. However, mice treated with EB in adulthood displayed better non-pup directed nest building behavior than when they were tested without EB treatment regardless of sex and time of gonadectomy. To examine whether the sensitivity to sex steroid hormones was altered due to differences in time without gonads prior to the testing, mice were also tested for female sex behavior and there were no differences between mice gonadectomized at P25 or P60, although this could not completely rule out the possibility that parental behavior is more sensitive to prolonged absence of steroid hormones than female sex behavior. These results suggest that the absence of gonads and thereby the absence of appropriate gonadal steroid hormones during puberty/adolescence may have a profound effect on pup directed parental behaviors in adult mice.
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Affiliation(s)
- Jasmina Kercmar
- Center for Animal Genomics, Veterinary Faculty, University of Ljubljana, Slovenia
| | - Tomaz Snoj
- Institute of Physiology, Pharmacology and Toxicology, Veterinary Faculty, University of Ljubljana, Slovenia
| | - Stuart A Tobet
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Gregor Majdic
- Center for Animal Genomics, Veterinary Faculty, University of Ljubljana, Slovenia; Institute of Physiology, Medical School, University of Maribor, Maribor, Slovenia.
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Yeo SH, Herbison AE. Estrogen-negative feedback and estrous cyclicity are critically dependent upon estrogen receptor-α expression in the arcuate nucleus of adult female mice. Endocrinology 2014; 155:2986-95. [PMID: 24905671 DOI: 10.1210/en.2014-1128] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The location and characteristics of cells within the brain that suppress GnRH neuron activity to contribute to the estrogen-negative feedback mechanism are poorly understood. Using adeno-associated virus (AAV)-mediated Cre-LoxP recombination in estrogen receptor-α (ERα) floxed mice (ERα(flox/flox)), we aimed to examine the role of ERα-expressing neurons located in the arcuate nucleus (ARN) in the estrogen-negative feedback mechanism. Bilateral injection of AAV-Cre into the ARN of ERα(flox/flox) mice (n = 14) resulted in the time-dependent ablation of up to 99% of ERα-immunoreactive cell numbers throughout the rostrocaudal length of the ARN. These mice were all acyclic by 5 weeks after AAV-Cre injections with most mice in constant estrous. Control wild-type mice injected with AAV-Cre (n = 13) were normal. Body weight was not altered in ERα(flox/flox) mice. After ovariectomy, a significant increment in LH secretion was observed in all genotypes, although its magnitude was reduced in ERα(flox/flox) mice. Acute and chronic estrogen-negative feedback were assessed by administering 17β-estradiol to mice as a bolus (LH measured 3 h later) or SILASTIC brand capsule implant (LH measured 5 d later). This demonstrated that chronic estrogen feedback was absent in ERα(flox/flox) mice, whereas the acute feedback was normal. These results reveal a critical role for ERα-expressing cells within the ARN in both estrous cyclicity and the chronic estrogen negative feedback mechanism in female mice. This suggests that ARN cells provide a key indirect, transsynpatic route through which estradiol suppresses the activity of GnRH neurons.
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Affiliation(s)
- Shel-Hwa Yeo
- Centre for Neuroendocrinology and Department of Physiology, University of Otago School of Medical Sciences, Dunedin 9054, New Zealand
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Cheong RY, Porteous R, Chambon P, Abrahám I, Herbison AE. Effects of neuron-specific estrogen receptor (ER) α and ERβ deletion on the acute estrogen negative feedback mechanism in adult female mice. Endocrinology 2014; 155:1418-27. [PMID: 24476134 DOI: 10.1210/en.2013-1943] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The negative feedback mechanism through which 17β-estradiol (E2) acts to suppress the activity of the GnRH neurons remains unclear. Using inducible and cell-specific genetic mouse models, we examined the estrogen receptor (ER) isoforms expressed by neurons that mediate acute estrogen negative feedback. Adult female mutant mice in which ERα was deleted from all neurons in the neonatal period failed to exhibit estrous cycles or negative feedback. Adult mutant female mice with neonatal neuronal ERβ deletion exhibited normal estrous cycles, but a failure of E2 to suppress LH secretion was seen in ovariectomized mice. Mutant mice with a GnRH neuron-selective deletion of ERβ exhibited normal cycles and negative feedback, suggesting no critical role for ERβ in GnRH neurons in acute negative feedback. To examine the adult roles of neurons expressing ERα, an inducible tamoxifen-based Cre-LoxP approach was used to ablate ERα from neurons that express calmodulin kinase IIα in adults. This resulted in mice with no estrous cycles, a normal increase in LH after ovariectomy, but an inability of E2 to suppress LH secretion. Finally, acute administration of ERα- and ERβ-selective agonists to adult ovariectomized wild-type mice revealed that activation of ERα suppressed LH secretion, whereas ERβ agonists had no effect. This study highlights the differences in adult reproductive phenotypes that result from neonatal vs adult ablation of ERα in the brain. Together, these experiments expand previous global knockout studies by demonstrating that neurons expressing ERα are essential and probably sufficient for the acute estrogen negative feedback mechanism in female mice.
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Affiliation(s)
- Rachel Y Cheong
- Centre for Neuroendocrinology (R.Y.C., R.P., I.A., A.E.H.), Department of Physiology, University of Otago School of Medical Sciences, Dunedin 9054, New Zealand; and Institut de Génétique et de Biologie Moléculaire et Cellulaire (P.C.), 67400 Illkirch, France
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Han X, Cheng W, Chen Z, Du X, Cao X, Zeng X. Active immunisation against pregnenolone reduces testicular steroidogenesis and GnRH synthesis in rabbits. Anim Reprod Sci 2014; 145:161-9. [DOI: 10.1016/j.anireprosci.2014.01.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 01/18/2014] [Accepted: 01/24/2014] [Indexed: 11/16/2022]
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Chimento A, Sirianni R, Casaburi I, Pezzi V. Role of estrogen receptors and g protein-coupled estrogen receptor in regulation of hypothalamus-pituitary-testis axis and spermatogenesis. Front Endocrinol (Lausanne) 2014; 5:1. [PMID: 24474947 PMCID: PMC3893621 DOI: 10.3389/fendo.2014.00001] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 01/03/2014] [Indexed: 11/13/2022] Open
Abstract
Male reproductive function is under the control of both gonadotropins and androgens through a negative feedback loop that involves the hypothalamus, pituitary, and testis known as hypothalamus-pituitary-gonadal axis (HPG). Indeed, estrogens also play an important role in regulating HPG axis but the study on relative contribution to the inhibition of gonadotropins secretion exerted by the amount of estrogens produced within the hypothalamus and/or the pituitary or by the amount of circulating estrogens is still ongoing. Moreover, it is known that the maintenance of spermatogenesis is controlled by gonadotropins and testosterone, the effects of which are modulated by a complex network of locally produced factors, including estrogens. Physiological effects of estrogens are mediated by the classical nuclear estrogen receptor alpha and estrogen receptor beta, which mediate both genomic and rapid signaling events. In addition, estrogens induce rapid non-genomic responses through a membrane-associated G protein-coupled estrogen receptor (GPER). Ours and other studies reported that, in the testis, GPER is expressed in both normal germ cells and somatic cells and it is involved in mediating the estrogen action in spermatogenesis controlling proliferative and/or apoptotic events. Interestingly, GPER expression has been revealed also in the hypothalamus and pituitary. However, its role in mediating estrogen rapid actions in this context is under investigation. Recent studies indicate that GPER is involved in modulating gonadotropin-releasing hormone (GnRH) release as well as gonadotropins secretion. In this review, we will summarize the current knowledge concerning the role of estrogen/estrogen receptors molecular pathways in regulating GnRH, follicle-stimulating hormone, and luteinizing hormone release at the hypothalamic and pituitary levels in males as well as in controlling specific testicular functions such as spermatogenesis, focusing our attention mainly on estrogen signaling mediated by GPER.
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Affiliation(s)
- Adele Chimento
- Laboratory of Applied Biology, Department of Pharmacy, Health and Nutrition Sciences, University of Calabria, Cosenza, Italy
| | - Rosa Sirianni
- Laboratory of Applied Biology, Department of Pharmacy, Health and Nutrition Sciences, University of Calabria, Cosenza, Italy
| | - Ivan Casaburi
- Laboratory of Applied Biology, Department of Pharmacy, Health and Nutrition Sciences, University of Calabria, Cosenza, Italy
| | - Vincenzo Pezzi
- Laboratory of Applied Biology, Department of Pharmacy, Health and Nutrition Sciences, University of Calabria, Cosenza, Italy
- *Correspondence: Vincenzo Pezzi, Laboratory of Applied Biology, Department of Pharmacy, Health and Nutrition Sciences, University of Calabria, Edificio Polifunzionale, Arcavacata di Rende, Cosenza 87036, Italy e-mail:
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Durán-Pastén ML, Fiordelisio T. GnRH-Induced Ca(2+) Signaling Patterns and Gonadotropin Secretion in Pituitary Gonadotrophs. Functional Adaptations to Both Ordinary and Extraordinary Physiological Demands. Front Endocrinol (Lausanne) 2013; 4:127. [PMID: 24137156 PMCID: PMC3786263 DOI: 10.3389/fendo.2013.00127] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Accepted: 08/31/2013] [Indexed: 11/13/2022] Open
Abstract
PITUITARY GONADOTROPHS ARE A SMALL FRACTION OF THE ANTERIOR PITUITARY POPULATION, YET THEY SYNTHESIZE GONADOTROPINS: luteinizing (LH) and follicle-stimulating (FSH), essential for gametogenesis and steroidogenesis. LH is secreted via a regulated pathway while FSH release is mostly constitutive and controlled by synthesis. Although gonadotrophs fire action potentials spontaneously, the intracellular Ca(2+) rises produced do not influence secretion, which is mainly driven by Gonadotropin-Releasing Hormone (GnRH), a decapeptide synthesized in the hypothalamus and released in a pulsatile manner into the hypophyseal portal circulation. GnRH binding to G-protein-coupled receptors triggers Ca(2+) mobilization from InsP3-sensitive intracellular pools, generating the global Ca(2+) elevations necessary for secretion. Ca(2+) signaling responses to increasing (GnRH) vary in stereotyped fashion from subthreshold to baseline spiking (oscillatory), to biphasic (spike-oscillatory or spike-plateau). This progression varies somewhat in gonadotrophs from different species and biological preparations. Both baseline spiking and biphasic GnRH-induced Ca(2+) signals control LH/FSH synthesis and exocytosis. Estradiol and testosterone regulate gonadotropin secretion through feedback mechanisms, while FSH synthesis and release are influenced by activin, inhibin, and follistatin. Adaptation to physiological events like the estrous cycle, involves changes in GnRH sensitivity and LH/FSH synthesis: in proestrus, estradiol feedback regulation abruptly changes from negative to positive, causing the pre-ovulatory LH surge. Similarly, when testosterone levels drop after orquiectomy the lack of negative feedback on pituitary and hypothalamus boosts both GnRH and LH secretion, gonadotrophs GnRH sensitivity increases, and Ca(2+) signaling patterns change. In addition, gonadotrophs proliferate and grow. These plastic changes denote a more vigorous functional adaptation in response to an extraordinary functional demand.
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Affiliation(s)
- Maria Luisa Durán-Pastén
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México (UNAM), México DF, México
| | - Tatiana Fiordelisio
- Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México (UNAM), México DF, México
- *Correspondence: Tatiana Fiordelisio, Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México (UNAM), Circuito exterior s/n. Ciudad Universitaria, C.P. 04510 México DF, México e-mail:
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Brock O, Bakker J, Baum MJ. Assessment of urinary pheromone discrimination, partner preference, and mating behaviors in female mice. Methods Mol Biol 2013; 1068:319-329. [PMID: 24014373 DOI: 10.1007/978-1-62703-619-1_24] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Behavioral testing methods are described for determining whether female mice can discriminate between volatile urinary pheromones of conspecifics of the same vs. opposite sex and/or in different endocrine conditions, for determining sexual partner preference, for quantifying receptive (lordosis) behavior, and for monitoring the expression of male-typical mounting behavior in female mice.
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Affiliation(s)
- Olivier Brock
- Netherlands Institute of Neuroscience, Amsterdam, The Netherlands
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Sánchez-Criado JE, Trudgen K, Millán Y, Blanco A, Monterde J, Garrido-Gracia JC, Gordon A, Aguilar R, Martín de las Mulas J, Ko C. Estrogen receptor (ESR) 2 partially offsets the absence of ESR1 in gonadotropes of pituitary-specific Esr1 knockout female mice. Reproduction 2012; 143:549-58. [DOI: 10.1530/rep-11-0214] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Estrogen receptor 1 and 2 (ESR1 and 2) mediate estrogen (E) action on gonadotrope function. While much is known about the effects of ESR1 on the gonadotrope, there is still some controversy regarding the effects of ESR2. To investigate the role of ESR2 in the gonadotrope, 45-day-old female mice of two different genotypes were used: wild type (WT) and pituitary (gonadotropes and thyrotropes)-specific Esr1 knockout (KO). All mice were ovariectomized (OVX) and 15 days later injected over 3 days with 2.5 μg 17β-estradiol (E2), 0.2 mg of the selective ESR1 or 2 agonists, propylpyrazole triol and diarylpropionitrile, respectively, or 0.1 ml oil. The day after treatment, anterior pituitary glands were dissected out for evaluation of gonadotrope ultrastructural morphology and pituitary immunohistochemical expression of progesterone receptor (Pgr (Pr)). Blood was collected and serum LH levels were assessed. Activation of ESR1 in WT mice resulted in the following: i) uterine ballooning and vaginal cornification, ii) negative feedback on LH secretion, iii) increased number of homogeneous (functional) gonadotropes, and iv) pituitary Pgr expression (35.9±2.0% of pituitary cells). Activation of ESR1 in KO mice induced normal uterine, vaginal, and LH secretion responses, but failed to increase the number of functional gonadotropes, and induced significantly lower Pgr expression (21.0±3.0% of pituitary cells) than in WT mice. Whilst activation of ESR2 had no significant effects in WT mice, it doubled the number of functional gonadotropes exhibited by KO mice injected with oil. It is concluded that E2 exerted its action in KO mouse gonadotropes via ESR2.
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Lv X, Guo Y, Shi D. Effects of quinestrol on reproductive hormone expression, secretion, and receptor levels in female Mongolian gerbils (Meriones unguiculatus). Theriogenology 2012; 77:1223-31. [DOI: 10.1016/j.theriogenology.2011.10.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 10/23/2011] [Accepted: 10/23/2011] [Indexed: 10/14/2022]
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Radovick S, Levine JE, Wolfe A. Estrogenic regulation of the GnRH neuron. Front Endocrinol (Lausanne) 2012; 3:52. [PMID: 22654870 PMCID: PMC3356008 DOI: 10.3389/fendo.2012.00052] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 03/16/2012] [Indexed: 11/17/2022] Open
Abstract
Reproductive function is regulated by the secretion of luteinizing hormone (LH) and follicle-stimulating hormone from the pituitary and the steroid hormones from the gonads. The dynamic changes in the levels of the reproductive hormones regulate secondary sex characteristics, gametogenesis, cellular function, and behavior. Hypothalamic GnRH neurons, with cell bodies located in the basal hypothalamus, represent the final common pathway for neuronally derived signals to the pituitary. As such, they serve as integrators of a dizzying array of signals including sensory inputs mediating information about circadian, seasonal, behavioral, pheromonal, and emotional cues. Additionally, information about peripheral physiological function may also be included in the integrative signal to the GnRH neuron. These signals may communicate information about metabolic status, disease, or infection. Gonadal steroid hormones arguably exert the most important effects on GnRH neuronal function. In both males and females, the gonadal steroid hormones exert negative feedback regulation on axis activity at both the level of the pituitary and the hypothalamus. These negative feedback loops regulate homeostasis of steroid hormone levels. In females, a cyclic reversal of estrogen feedback produces a positive feedback loop at both the hypothalamic and pituitary levels. Central positive feedback results in a dramatic increase in GnRH secretion (Moenter et al., 1992; Xia et al., 1992; Clarke, 1993; Sisk et al., 2001). This is coupled with an increase in pituitary sensitivity to GnRH (Savoy-Moore et al., 1980; Turzillo et al., 1995), which produces the massive surge in secretion of LH that triggers ovulation. While feedback regulation of the axis in males is in part mediated by estrogen receptors (ER), there is not a clear consensus as to the relative role of ER versus AR signaling in males (Lindzey et al., 1998; Wersinger et al., 1999). Therefore, this review will focus on estrogenic signaling in the female.
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Affiliation(s)
- Sally Radovick
- Department of Pediatrics, Johns Hopkins University School of MedicineBaltimore, MD, USA
| | - Jon E. Levine
- Wisconsin National Primate Research CenterMadison, WI, USA
| | - Andrew Wolfe
- Department of Pediatrics, Johns Hopkins University School of MedicineBaltimore, MD, USA
- *Correspondence: Andrew Wolfe, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. e-mail:
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Davis TL, Whitesell JD, Cantlon JD, Clay CM, Nett TM. Does a nonclassical signaling mechanism underlie an increase of estradiol-mediated gonadotropin-releasing hormone receptor binding in ovine pituitary cells? Biol Reprod 2011; 85:770-8. [PMID: 21734267 DOI: 10.1095/biolreprod.111.091926] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Estradiol-17beta (E2) is the major regulator of GnRH receptor (GnRHR) gene expression and number during the periovulatory period; however, the mechanisms underlying E2 regulation of the GNRHR gene remain undefined. Herein, we find that E2 conjugated to BSA (E2-BSA) mimics the stimulatory effect of E2 on GnRH binding in primary cultures of ovine pituitary cells. The time course for maximal GnRH analog binding was similar for both E2 and E2-BSA. The ability of E2 and E2-BSA to increase GnRH analog binding was blocked by the estrogen receptor (ER) antagonist ICI 182,780. Also, increased GnRH analog binding in response to E2 and the selective ESR1 agonist propylpyrazole triol was blocked by expression of a dominant-negative form of ESR1 (L540Q). Thus, membrane-associated ESR1 is the likely candidate for mediating E2 activation of the GNRHR gene. As cAMP response element binding protein (CREB) is an established target for E2 activation in gonadotrophs, we next explored a potential role for this protein as an intracellular mediator of the E2 signal. Consistent with this possibility, adenoviral-mediated expression of a dominant-negative form of CREB (A-CREB) completely abolished the ability of E2 to increase GnRH analog binding in primary cultures of ovine pituitary cells. Finally, the presence of membrane-associated E2 binding sites on ovine pituitary cells was demonstrated using a fluorescein isothiocyanate conjugate of E2-BSA. We suggest that E2 regulation of GnRHR number during the preovulatory period reflects a membrane site of action and may proceed through a nonclassical signaling mechanism, specifically a CREB-dependent pathway.
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Affiliation(s)
- Tracy L Davis
- Animal Reproduction and Biotechnology Laboratory, Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
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Cao J, Patisaul HB, Petersen SL. Aryl hydrocarbon receptor activation in lactotropes and gonadotropes interferes with estradiol-dependent and -independent preprolactin, glycoprotein alpha and luteinizing hormone beta gene expression. Mol Cell Endocrinol 2011; 333:151-9. [PMID: 21187122 PMCID: PMC3059512 DOI: 10.1016/j.mce.2010.12.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 12/15/2010] [Accepted: 12/20/2010] [Indexed: 01/13/2023]
Abstract
Arylhydrocarbon receptor (Ahr) activation by 2,3,7,8-tetrachlordibenzo-p-dioxin (TCDD) interferes with female reproductive functions, but there is little information on the specific targets of TCDD in the hypothalamic-pituitary-gonadal (HPG) axis. In these studies, we found that TCDD upregulated known AhR target genes, cytochrome p450 1a1 (Cyp1a1), Cyp1a2 and Cyp1b1 in the rat pituitary gland. Moreover, 75% of pituitary lactotropes and 45% of gonadotropes contained Ahr mRNA, and most Ahr-containing cells were estrogen receptor 1 (Esr1)-positive. TCDD abrogated estradiol (E(2))-induced prolactin (Prl) expression in vivo and in vitro; conversely, E(2) blocked TCDD upregulation of luteinizing hormone beta (Lhb) and glycoprotein hormone alpha polypeptide (Cga) expression. TCDD had no effect on levels of Ahr mRNA, but upregulated Esr1 mRNA. E(2) independently repressed Ahr and Esr1 expression and blocked TCDD upregulation of Esr1. Thus, complex interactions between Ahr and Esr alter Prl and luteinizing hormone (LH) synthesis by direct actions in lactotropes and gonadotropes. These findings provide important insights into how TCDD disrupts female reproductive functions.
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Affiliation(s)
- JinYan Cao
- Molecular and Cellular Biology Graduate Program, 435 Morrill I North, University of Massachusetts Amherst, 637 North Pleasant Street, Amherst, MA 01003-9298
- Department of Biology, 127 David Clark Labs, North Carolina State University, Raleigh, NC 27695
| | - Heather B. Patisaul
- Department of Biology, 127 David Clark Labs, North Carolina State University, Raleigh, NC 27695
| | - Sandra L. Petersen
- Molecular and Cellular Biology Graduate Program, 435 Morrill I North, University of Massachusetts Amherst, 637 North Pleasant Street, Amherst, MA 01003-9298
- Department of Veterinary and Animal Sciences, 661 North Pleasant Street, University of Massachusetts, Amherst MA 01003
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Singh SP, Wolfe A, Ng Y, DiVall SA, Buggs C, Levine JE, Wondisford FE, Radovick S. Impaired estrogen feedback and infertility in female mice with pituitary-specific deletion of estrogen receptor alpha (ESR1). Biol Reprod 2009; 81:488-96. [PMID: 19439729 DOI: 10.1095/biolreprod.108.075259] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Mice lacking estrogen receptor alpha in the pituitary gonadotroph (PitEsr1KO) were generated to determine the physiologic role of pituitary estrogen signaling in the reproductive axis. PitEsr1KO female mice are subfertile or infertile and have elevated levels of serum luteinizing hormone (LH) and LH beta subunit gene expression, reflecting a lack of estrogen negative feedback effect on the gonadotroph. While serum LH values are elevated in PitEsr1KO mice, the degree of elevation is much less than that observed in ESR1-null mice, indicating that the hypothalamus must also have an important role in estrogen negative feedback. PitEsr1KO mice also demonstrate a defect in estrogen positive feedback, as surge LH values and estrous cyclicity are absent in these mice. Although sex steroid feedback in the reproductive axis is thought to involve discrete anatomic regions that mediate either a positive or negative estrogen effect, PitEsr1KO mice demonstrate novel evidence that localizes both estrogen positive feedback and estrogen negative feedback to the gonadotroph, which suggests that they may be mechanistically related.
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Affiliation(s)
- Surya P Singh
- Divisions of Pediatric Endocrinology and Metabolism, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
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Conditional inactivation of androgen receptor gene in the nervous system: effects on male behavioral and neuroendocrine responses. J Neurosci 2009; 29:4461-70. [PMID: 19357272 DOI: 10.1523/jneurosci.0296-09.2009] [Citation(s) in RCA: 168] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Testosterone (T) profoundly influences central sexual differentiation and functions. In the brain, T signals either directly through androgen receptor (AR) or indirectly through estrogen receptor (ER) following aromatization into E2 (17-beta-estradiol). As T, through AR, also controls peripheral male sexual differentiation, the relative contribution of central AR in T-mediated regulation of behavioral and neuroendocrine responses still remains unclear. To address this question, we generated, by using Cre-loxP technology, mice selectively lacking AR expression in the nervous system. The mutant male urogenital tract was normally developed, and mice were able to produce offspring. Nonetheless, sexual motivation and performance as well as aggressive behaviors were affected. Only a low percentage of males displayed a complete sexual behavior and offensive attacks. The latency to show masculine behaviors was increased and copulation length prolonged. Erectile activity during mating was also altered. These alterations occurred despite increased levels of T and its metabolites, and an unaffected number of ERalpha-immunoreactive cells. Olfactory preference and neuronal activation, mapped by Fos immunoreactivity, following exposure to estrus female-soiled bedding were also normal. At comparable T levels, greater differences in masculine behaviors were observed between gonadectomized control and mutant males. AR invalidation in the nervous system also disrupted the somatotropic axis since mutant males exhibited growth retardation and decreased serum levels of insulin-like growth factor I. Our findings show that central AR is required in T-induced regulation of male-typical behaviors and gonadotrope and somatotropic axes. This genetic model offers a unique opportunity in the understanding of AR's role in cerebral functions of T.
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Christian CA, Glidewell-Kenney C, Jameson JL, Moenter SM. Classical estrogen receptor alpha signaling mediates negative and positive feedback on gonadotropin-releasing hormone neuron firing. Endocrinology 2008; 149:5328-34. [PMID: 18635656 PMCID: PMC2584581 DOI: 10.1210/en.2008-0520] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Accepted: 07/09/2008] [Indexed: 01/22/2023]
Abstract
During the female reproductive cycle, the neuroendocrine action of estradiol switches from negative feedback to positive feedback to initiate the preovulatory GnRH and subsequent LH surges. Estrogen receptor-alpha (ERalpha) is required for both estradiol negative and positive feedback regulation of LH. ERalpha may signal through estrogen response elements (EREs) in DNA and/or via ERE-independent pathways. Previously, a knock-in mutant allele (ERalpha-/AA) that selectively restores ERE-independent signaling onto the ERalpha-/- background was shown to confer partial negative but not positive estradiol feedback on serum LH. The current study investigated the roles of the ERE-dependent and ERE-independent ERalpha pathways for estradiol feedback at the level of GnRH neuron firing activity. The above ERalpha genetic models were crossed with GnRH-green fluorescent protein mice to enable identification of GnRH neurons in brain slices. Targeted extracellular recordings were used to monitor GnRH neuron firing activity using an ovariectomized, estradiol-treated mouse model that exhibits diurnal switches between negative and positive feedback. In wild-type mice, GnRH neuron firing decreased in response to estradiol during negative feedback and increased during positive feedback. In contrast, both positive and negative responses to estradiol were absent in GnRH neurons from ERalpha-/- and ERalpha-/AA mice. ERE-dependent signaling is thus required to increase GnRH neuron firing to generate a GnRH/LH surge. Furthermore, ERE-dependent and -independent ERalpha signaling pathways both appear necessary to mediate estradiol negative feedback on serum LH levels, suggesting central and pituitary estradiol feedback may use different combinations of ERalpha signaling pathways.
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Affiliation(s)
- Catherine A Christian
- Neuroscience Graduate Program, Department of Medicine, University of Virginia, Charlottesville, Virginia 22908, USA
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McDevitt MA, Glidewell-Kenney C, Jimenez MA, Ahearn PC, Weiss J, Jameson JL, Levine JE. New insights into the classical and non-classical actions of estrogen: evidence from estrogen receptor knock-out and knock-in mice. Mol Cell Endocrinol 2008; 290:24-30. [PMID: 18534740 PMCID: PMC2562461 DOI: 10.1016/j.mce.2008.04.003] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Accepted: 04/04/2008] [Indexed: 02/07/2023]
Abstract
Estrogen receptor alpha (ERalpha) mediates estrogen (E2) actions in the brain and is critical for normal reproductive function and behavior. In the classical pathway, ERalpha binds to estrogen response elements (EREs) to regulate gene transcription. ERalpha can also participate in several non-classical pathways, including ERE-independent gene transcription via protein-protein interactions with transcription factors and rapid, non-genotropic pathways. To distinguish between ERE-dependent and ERE-independent mechanisms of E2 action in vivo, we have created ERalpha null mice that possess an ER knock-in mutation (E207A/G208A; "AA"), in which the mutant ERalpha cannot bind to DNA but retains activity in ERE-independent pathways (ERalpha(-/AA) mice). Understanding the molecular mechanisms of ERalpha action will be helpful in developing pharmacological therapies that differentiate between ERE-dependent and ERE-independent processes. This review focuses on how the ERalpha(-/AA) model has contributed to our knowledge of ERalpha signaling mechanisms in estrogen regulation of the reproductive axis and sexual behavior.
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Affiliation(s)
- Melissa A. McDevitt
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois 60208, USA
| | - Christine Glidewell-Kenney
- Department of Endocrinology, Metabolism and Molecular Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611 USA
| | - Mariana A. Jimenez
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois 60208, USA
| | - Patrick C. Ahearn
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois 60208, USA
| | - Jeffrey Weiss
- Department of Endocrinology, Metabolism and Molecular Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611 USA
| | - J. Larry Jameson
- Department of Endocrinology, Metabolism and Molecular Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611 USA
| | - Jon E. Levine
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois 60208, USA
- Corresponding author: Jon E. Levine, PhD, 2205 Tech Drive, Evanston, IL 60208, Tel: 847-491-7180, Fax: 847-491-5211,
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Glidewell-Kenney C, Weiss J, Hurley LA, Levine JE, Jameson JL. Estrogen receptor alpha signaling pathways differentially regulate gonadotropin subunit gene expression and serum follicle-stimulating hormone in the female mouse. Endocrinology 2008; 149:4168-76. [PMID: 18467444 PMCID: PMC2488215 DOI: 10.1210/en.2007-1807] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Estrogen, acting via estrogen receptor (ER)alpha, regulates serum gonadotropin levels and pituitary gonadotropin subunit expression. However, the cellular pathways mediating this regulation are unknown. ERalpha signals through classical estrogen response element (ERE)-dependent genomic as well as nonclassical ERE-independent genomic and nongenomic pathways. Using targeted mutagenesis in mice to disrupt ERalpha DNA binding activity, we previously demonstrated that ERE-independent signaling is sufficient to suppress serum LH levels. In this study, we examined the relative roles of ERE-dependent and -independent estrogen signaling in estrogen regulation of LH, FSH, prolactin, and activin/inhibin subunit gene expression, pituitary LH and FSH protein content, and serum FSH levels. ERE-independent signaling was not sufficient for estrogen to induce pituitary prolactin mRNA or suppress pituitary LHbeta mRNA, LH content, or serum FSH in estrogen-treated ovariectomized mice. However, ERE-independent signaling was sufficient to reduce pituitary glycoprotein hormone alpha-subunit, FSHbeta, and activin-betaB mRNA expression. Together with previous serum LH results, these findings suggest ERE-independent ERalpha signaling suppresses serum LH via reduced secretion, not synthesis. Additionally, ERE-dependent and ERE-independent ERalpha pathways may distinctly regulate steps involved in the synthesis and secretion of FSH.
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Affiliation(s)
- C Glidewell-Kenney
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
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Abstract
Oestrogen receptor beta (ERbeta) was discovered more than 10 years ago. It is widely distributed in the brain. In some areas, such as the entorhinal cortex, it is present as the only ER, whereas in other regions, such as the bed nucleus of the stria terminalis and preoptic area, it can be found co-expressed with ERalpha, often within the same neurones. These ERs share ligands, and there are several complex relationships between the two receptors. Initially, the relationship between them was labelled as 'yin/yang', meaning that the actions of each complemented those of the other, but now, years later, other relationships have been described. Based on evidence from neuroendocrine and behavioural studies, three types of interactions between the two oestrogen receptors are described in this review. The first relationship is antagonistic; this is evident from studies on the role of oestrogen in spatial learning. When oestradiol is given in a high, chronic dose, spatial learning is impaired. This action of oestradiol requires ERalpha, and when ERbeta is not functional, lower doses of oestradiol have this negative effect on behaviour. The second relationship between the two receptors is one that is synergistic, and this is illustrated in the combined effects of the two receptors on the production of the neuropeptide oxytocin and its receptor. The third relationship is sequential; separate actions of the two receptors are postulated in activation and organisation of sexually dimorphic reproductive behaviours. Future studies on all of these topics will inform us about how ER selective ligands might affect oestrogen functions at the organismal level.
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Affiliation(s)
- E F Rissman
- Department of Biochemistry and Molecular Genetics, Program in Neuroscience, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
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Attardi BJ, Pham TC, Radler LC, Burgenson J, Hild SA, Reel JR. Dimethandrolone (7alpha,11beta-dimethyl-19-nortestosterone) and 11beta-methyl-19-nortestosterone are not converted to aromatic A-ring products in the presence of recombinant human aromatase. J Steroid Biochem Mol Biol 2008; 110:214-22. [PMID: 18555683 PMCID: PMC2575079 DOI: 10.1016/j.jsbmb.2007.11.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2007] [Accepted: 11/20/2007] [Indexed: 10/22/2022]
Abstract
Dimethandrolone undecanoate (DMAU: 7alpha,11beta-dimethyl-19-nortestosterone 17beta-undecanoate) is a potent orally active androgen in development for hormonal therapy in men. Cleavage of the 17beta-ester bond by esterases in vivo leads to liberation of the biologically active androgen, dimethandrolone (DMA), a 19-norandrogen. For hormone replacement in men, administration of C19 androgens such as testosterone (T) may lead to elevations in circulating levels of estrogens due to aromatization. As several reports have suggested that certain 19-norandrogens may serve as substrates for the aromatase enzyme and are converted to the corresponding aromatic A-ring products, it was important to investigate whether DMA, the related compound, 11beta-methyl-19-nortestosterone (11beta-MNT), also being tested for hormonal therapy in men, and other 19-norandrogens can be converted to aromatic A-ring products by human aromatase. The hypothetical aromatic A-ring product corresponding to each substrate was obtained by chemical synthesis. These estrogens bound with high affinity to purified recombinant human estrogen receptors (ER) alpha and beta in competitive binding assays (IC50's: 5-12 x 10(-9) M) and stimulated transcription of 3XERE-luciferase in T47Dco human breast cancer cells with a potency equal to or greater than that of estradiol (E2) (EC50's: 10(-12) to 10(-11) M). C19 androgens (T, 17alpha-methyltestosterone (17alpha-MT), androstenedione (AD), and 16alpha-hydroxyandrostenedione (16alpha-OHAD)), 19-norandrogens (DMA, 11beta-MNT, 19-nortestosterone (19-NT), and 7alpha-methyl-19-nortestosterone (MENT)) or the structurally similar 19-norprogestin, norethindrone (NET) were incubated at 50 microM with recombinant human aromatase for 10-180 min at 37 degrees C. The reactions were terminated by extraction with acetonitrile and centrifugation, and substrate and potential product were separated by HPLC. Retention times were monitored by UV absorption, and UV peaks were quantified using standard curves. Aromatization of the positive controls, T, AD, and 16alpha-OHAD was linear for 40-60 min, and conversion of T or AD was complete by 120 min. The nonsteroidal aromatase inhibitor, letrozole, demonstrated concentration-dependent suppression of T aromatization. Under the same conditions, there was no detectable conversion of DMA, 11beta-MNT, or NET to their respective hypothetical aromatic A-ring products during incubation times up to 180 min. Aromatization of MENT and 19-NT proceeded slowly and was limited. Collectively, these data support the notion that in the absence of the C19-methyl group, which is the site of attack by oxygen, aromatization of androgenic substrates proceeds slowly or not at all and that this reaction is impeded by the presence of a methyl group at the 11beta position.
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Affiliation(s)
- Barbara J Attardi
- Division of Reproductive Endocrinology and Toxicology, BIOQUAL Inc., 9600 Medical Center Drive, Rockville, MD 20850, USA.
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Caba M, Tovar A, Silver R, Mogado E, Meza E, Zavaleta Y, Juárez C. Nature's food anticipatory experiment: entrainment of locomotor behavior, suprachiasmatic and dorsomedial hypothalamic nuclei by suckling in rabbit pups. Eur J Neurosci 2008; 27:432-43. [PMID: 18215239 DOI: 10.1111/j.1460-9568.2008.06017.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In nature and under laboratory conditions, dams nurse rabbit pups once daily for a duration of fewer than 5 min. The present study explored neural mechanisms mediating the timing of nursing in this natural model of food anticipatory activity, focussing on the suprachiasmatic nucleus (SCN), the locus of the master circadian clock and on the dorsomedial hypothalamic nucleus (DMH), a region implicated in timing of food-entrained behavior. Rabbit pups are born in the dark, with eyelids closed. Nursing visits to the litters also occurs during the dark phase. To explore the effect of the timing of feeding, pups were maintained in constant darkness, while females housed in a light-dark cycle were permitted to nurse their pups either during the night (night-fed group) or day (day-fed group). All pups exhibited anticipatory locomotor activity before daily nursing. In the SCN, PER1 and FOS peaked during the night in both groups, with a longer duration of elevated protein expression in the night-fed group. In contrast, DMH peak PER1 expression occurred 8 h after pups were fed, corresponding to the shift in timing of nursing. Comparison of nursed and 48 h fasted pups indicates that the timing of PER1 expression was similar in the SCN and DMH, with fewer PER1-positive cells in the latter group. The results indicate that rabbit pups show food anticipatory activity, and that timing of nursing differentially affects PER1 expression in the SCN and DMH.
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Affiliation(s)
- Mario Caba
- Lab. Biol. of Reproduction, IIB, Universidad Veracruzana, A.P. # 114, Xalapa 91000, Ver. Mexico.
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