1
|
Arismendi D, Alanis C, Richter P, Paredes AH. Effect of triclosan exposure on ovarian hormones, trace elements and growth in female rats. CHEMOSPHERE 2022; 307:135964. [PMID: 35970220 DOI: 10.1016/j.chemosphere.2022.135964] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 08/01/2022] [Accepted: 08/02/2022] [Indexed: 06/15/2023]
Abstract
Triclosan (TCS) is an antibacterial compound used mainly in personal care products. Its widespread use for decades has made it one of the most widely detected compounds in environmental matrices and in biological fluids. Although it has been shown to be an endocrine disruptor in rats and aquatic species, its safe use by humans is unclear. The aim of the present study was to evaluate the effects of exposure to TCS in female rats. To this end, 14 rats were divided into two groups and fed daily as follows: the control group with sesame oil and the TCS group at a dose of 50 mg/kg/day for 28 days. Any signs of toxicity in the rats were observed daily, and the weight and phase of the estrous cycle were recorded. At the end, the rats were decapitated, the serum and ovaries were collected. The levels of testosterone and progesterone in serum were determined by immunoassay and mass spectrometry. Estradiol (in serum) and kisspeptin-10 (in serum and ovary) were measured only by immunoassays. Trace elements were determined by inductively coupled plasma-mass spectrometry (ICP-MS). The weight gain study of the rats showed a significant decrease by exposure to TCS, while the estrous cycle was not significantly affected compared to the control. The optimized methods based on mass spectrometry showed a significant decrease in the levels of progesterone and testosterone due to exposure to TCS. In addition, elements determined by ICP-MS in rat serum showed significant changes in calcium, lithium and aluminum due to TCS treatment. Finally, the kisspeptin-10 levels did not show a negative effect due to the treatment by TCS. The results suggest that medium-term exposure to TCS did not significantly alter estrous cyclicity but caused alterations in growth, sex hormone levels and some elements in the rat serum.
Collapse
Affiliation(s)
- Daniel Arismendi
- Department of Inorganic and Analytical Chemistry, Faculty of Chemical and Pharmaceutical Sciences, University of Chile, P.O. Box 233, Santiago, Chile
| | - Constanza Alanis
- Department of Biochemistry and Molecular Biology, Faculty of Chemical and Pharmaceutical Sciences, University of Chile, P.O. Box 233, Santiago, Chile
| | - Pablo Richter
- Department of Inorganic and Analytical Chemistry, Faculty of Chemical and Pharmaceutical Sciences, University of Chile, P.O. Box 233, Santiago, Chile
| | - Alfonso H Paredes
- Department of Biochemistry and Molecular Biology, Faculty of Chemical and Pharmaceutical Sciences, University of Chile, P.O. Box 233, Santiago, Chile.
| |
Collapse
|
2
|
PASSARELLI A, LETTIERI A, DEMIRCI TN, MAGNI P. Gonadotropin-releasing hormone-secreting neuron development and function: an update. Minerva Endocrinol (Torino) 2022; 47:58-69. [DOI: 10.23736/s2724-6507.22.03683-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
3
|
Emanuel RHK, Roberts J, Docherty PD, Lunt H, Campbell RE, Möller K. A review of the hormones involved in the endocrine dysfunctions of polycystic ovary syndrome and their interactions. Front Endocrinol (Lausanne) 2022; 13:1017468. [PMID: 36457554 PMCID: PMC9705998 DOI: 10.3389/fendo.2022.1017468] [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: 08/12/2022] [Accepted: 10/27/2022] [Indexed: 11/16/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) affects up to 20% of women but remains poorly understood. It is a heterogeneous condition with many potential comorbidities. This review offers an overview of the dysregulation of the reproductive and metabolic systems associated with PCOS. Review of the literature informed the development of a comprehensive summarizing 'wiring' diagram of PCOS-related features. This review provides a justification for each diagram aspect from the relevant academic literature, and explores the interactions between the hypothalamus, ovarian follicles, adipose tissue, reproductive hormones and other organ systems. The diagram will provide an efficient and useful tool for those researching and treating PCOS to understand the current state of knowledge on the complexity and variability of PCOS.
Collapse
Affiliation(s)
- Rebecca H. K. Emanuel
- Department of Mechanical Engineering, University of Canterbury, Christchurch, New Zealand
| | - Josh Roberts
- Department of Mechanical Engineering, University of Canterbury, Christchurch, New Zealand
| | - Paul D. Docherty
- Department of Mechanical Engineering, University of Canterbury, Christchurch, New Zealand
- Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
- *Correspondence: Paul D. Docherty,
| | - Helen Lunt
- Diabetes Services, Te Whatu Ora Waitaha Canterbury, Canterbury, New Zealand
- Department of Medicine, University of Otago, Christchurch, New Zealand
| | - Rebecca E. Campbell
- School of Biomedical Sciences, Department of Physiology, Centre for Neuroendocrinology, University of Otago, Dunedin, New Zealand
| | - Knut Möller
- Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
| |
Collapse
|
4
|
Schaefer J, Vilos AG, Vilos GA, Bhattacharya M, Babwah AV. Uterine kisspeptin receptor critically regulates epithelial estrogen receptor α transcriptional activity at the time of embryo implantation in a mouse model. Mol Hum Reprod 2021; 27:gaab060. [PMID: 34524460 PMCID: PMC8786495 DOI: 10.1093/molehr/gaab060] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 09/07/2021] [Indexed: 12/14/2022] Open
Abstract
Embryo implantation failure is a major cause of infertility in women of reproductive age and a better understanding of uterine factors that regulate implantation is required for developing effective treatments for female infertility. This study investigated the role of the uterine kisspeptin receptor (KISS1R) in the molecular regulation of implantation in a mouse model. To conduct this study, a conditional uterine knockout (KO) of Kiss1r was created using the Pgr-Cre (progesterone receptor-CRE recombinase) driver. Reproductive profiling revealed that while KO females exhibited normal ovarian function and mated successfully to stud males, they exhibited significantly fewer implantation sites, reduced litter size and increased neonatal mortality demonstrating that uterine KISS1R is required for embryo implantation and a healthy pregnancy. Strikingly, in the uterus of Kiss1r KO mice on day 4 (D4) of pregnancy, the day of embryo implantation, KO females exhibited aberrantly elevated epithelial ERα (estrogen receptor α) transcriptional activity. This led to the temporal misexpression of several epithelial genes [Cftr (Cystic fibrosis transmembrane conductance regulator), Aqp5 (aquaporin 5), Aqp8 (aquaporin 8) and Cldn7 (claudin 7)] that mediate luminal fluid secretion and luminal opening. As a result, on D4 of pregnancy, the lumen remained open disrupting the final acquisition of endometrial receptivity and likely accounting for the reduction in implantation events. Our data clearly show that uterine KISS1R negatively regulates ERα signaling at the time of implantation, in part by inhibiting ERα overexpression and preventing detrimentally high ERα activity. To date, there are no reports on the regulation of ERα by KISS1R; therefore, this study has uncovered an important and powerful regulator of uterine ERα during early pregnancy.
Collapse
Affiliation(s)
- Jennifer Schaefer
- Laboratory of Human Growth and Reproductive Development, Department of Pediatrics, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
- School of Graduate Studies, Joint Graduate Program in Toxicology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Angelos G Vilos
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynaecology, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - George A Vilos
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynaecology, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Moshmi Bhattacharya
- Department of Medicine, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
- Child Health Institute of New Jersey, New Brunswick, NJ, USA
| | - Andy V Babwah
- Laboratory of Human Growth and Reproductive Development, Department of Pediatrics, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
- School of Graduate Studies, Joint Graduate Program in Toxicology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
- Child Health Institute of New Jersey, New Brunswick, NJ, USA
| |
Collapse
|
5
|
Uenoyama Y, Nagae M, Tsuchida H, Inoue N, Tsukamura H. Role of KNDy Neurons Expressing Kisspeptin, Neurokinin B, and Dynorphin A as a GnRH Pulse Generator Controlling Mammalian Reproduction. Front Endocrinol (Lausanne) 2021; 12:724632. [PMID: 34566891 PMCID: PMC8458932 DOI: 10.3389/fendo.2021.724632] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/23/2021] [Indexed: 01/16/2023] Open
Abstract
Increasing evidence accumulated during the past two decades has demonstrated that the then-novel kisspeptin, which was discovered in 2001, the known neuropeptides neurokinin B and dynorphin A, which were discovered in 1983 and 1979, respectively, and their G-protein-coupled receptors, serve as key molecules that control reproduction in mammals. The present review provides a brief historical background and a summary of our recent understanding of the roles of hypothalamic neurons expressing kisspeptin, neurokinin B, and dynorphin A, referred to as KNDy neurons, in the central mechanism underlying gonadotropin-releasing hormone (GnRH) pulse generation and subsequent tonic gonadotropin release that controls mammalian reproduction.
Collapse
|
6
|
Simonneaux V. A Kiss to drive rhythms in reproduction. Eur J Neurosci 2018; 51:509-530. [DOI: 10.1111/ejn.14287] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 10/08/2018] [Accepted: 11/19/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Valérie Simonneaux
- Institut des Neurosciences Cellulaires et IntégrativesCNRSUniversité de Strasbourg Strasbourg France
| |
Collapse
|
7
|
McIlwraith EK, Loganathan N, Belsham DD. Phoenixin Expression Is Regulated by the Fatty Acids Palmitate, Docosahexaenoic Acid and Oleate, and the Endocrine Disrupting Chemical Bisphenol A in Immortalized Hypothalamic Neurons. Front Neurosci 2018; 12:838. [PMID: 30524225 PMCID: PMC6262291 DOI: 10.3389/fnins.2018.00838] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 10/29/2018] [Indexed: 01/22/2023] Open
Abstract
Phoenixin (PNX) is a newly identified reproductive peptide required for the estrous cycle. It is most highly expressed in the hypothalamus, where it is a positive regulator of gonadotropin-releasing hormone (GnRH) and kisspeptin. However, it is unknown what signals lie upstream of Pnx to coordinate its effects on GnRH and kisspeptin. We investigated the effects of the hormones, estrogen and leptin; the fatty acids, palmitate, docosahexaenoic acid (DHA), oleate and palmitoleate; and the endocrine disrupting chemical BPA on Pnx mRNA levels. We also examined whether the signaling pathways of nitric oxide, lipopolysaccharide, cAMP and protein kinase C could alter Pnx expression. Immortalized hypothalamic neurons were treated from 2 to 24 h with these compounds and Pnx mRNA levels were measured with RT-qPCR. Unexpectedly, only BPA as well as the fatty acids, palmitate, DHA and oleate, could alter Pnx expression; therefore suggesting that Pnx may fulfill a nutrient-sensing role in the hypothalamus. Our study is the first to delineate potential regulators of this novel neuropeptide, and our findings provide some insight into the functional role of PNX in the hypothalamus.
Collapse
Affiliation(s)
- Emma K McIlwraith
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Neruja Loganathan
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Denise D Belsham
- Department of Physiology, University of Toronto, Toronto, ON, Canada.,Department of Obstetrics and Gynaecology, University of Toronto, Toronto, ON, Canada.,Department of Medicine, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
8
|
Abstract
The life of a human female is characterized from teenage years by monthly menstruation which ceases (the menopause) typically between the age of 40 and 60 years. The potential for reproduction declines and ceases as the ovaries become depleted of follicles. A transition period in mid-life, for 2 to 10 years, when menstruation is less regular is called the perimenopause. The menopause is associated with a significant decline in plasma concentrations of sex hormones, an increase in the concentrations of the gonadotrophins and changes in other hormones such as the inhibins. These changes are superimposed with effects of aging, social and metabolic factors, daily activity and well-being. Although the menopause is entirely natural, in some cases ovarian failure can occur earlier than usual; this is pathological and warrants careful biochemical investigations to distinguish it from conditions causing infertility. Elderly females are affected by a range of clinical disorders including endocrine, cardiovascular, skeletal, urogenital tract and immunological systems, body mass, vasomotor tone, mood and sleep pattern. Reference intervals for many diagnostic biochemical tests for the menopause need to be used when interpreting results in clinical investigations for patient management. The standardization and harmonization of assays are being addressed. Many women now choose to develop their career before bearing children, and the health service has had to change services around this. This review does not cover screening for and tests during pregnancy. The review is timely since the population is aging and there will be more demand on healthcare services.
Collapse
Affiliation(s)
- John W Honour
- Institute of Women's Health, University College London, London, UK
| |
Collapse
|
9
|
d'Anglemont de Tassigny X, Jayasena C, Murphy KG, Dhillo WS, Colledge WH. Mechanistic insights into the more potent effect of KP-54 compared to KP-10 in vivo. PLoS One 2017; 12:e0176821. [PMID: 28464043 PMCID: PMC5413024 DOI: 10.1371/journal.pone.0176821] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 04/18/2017] [Indexed: 01/03/2023] Open
Abstract
Kisspeptins regulate the mammalian reproductive axis by stimulating release of gonadotrophin releasing hormone (GnRH). Different length kisspeptins (KP) are found of 54, 14, 13 or 10 amino-acids which share a common C-terminal 10-amino acid sequence. KP-54 and KP-10 have been widely used to stimulate the reproductive axis but data suggest that KP-54 and KP-10 are not equally effective at eliciting reproductive hormone secretion after peripheral delivery. To confirm this, we analysed the effect of systemic administration of KP-54 or KP-10 on luteinizing hormone (LH) secretion into the bloodstream of male mice. Plasma LH measurements 10 min or 2 hours after kisspeptin injection showed that KP-54 can sustain LH release far longer than KP-10, suggesting a differential mode of action of the two peptides. To investigate the mechanism for this, we evaluated the pharmacokinetics of the two peptides in vivo and their potential to cross the blood brain barrier (BBB). We found that KP-54 has a half-life of ~32 min in the bloodstream, while KP-10 has a half-life of ~4 min. To compensate for this difference in half-life, we repeated injections of KP-10 every 10 min over 1 hr but failed to reproduce the sustained rise in LH observed after a single KP-54 injection, suggesting that the failure of KP-10 to sustain LH release may not just be related to peptide clearance. We tested the ability of peripherally administered KP-54 and KP-10 to activate c-FOS in GnRH neurons behind the blood brain barrier (BBB) and found that only KP-54 could do this. These data are consistent with KP-54 being able to cross the BBB and suggest that KP10 may be less able to do so.
Collapse
Affiliation(s)
- Xavier d'Anglemont de Tassigny
- Reproductive Physiology Group, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Channa Jayasena
- Section of Endocrinology and Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London at Hammersmith Campus, Commonwealth Building, London, United Kingdom
| | - Kevin G. Murphy
- Section of Endocrinology and Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London at Hammersmith Campus, Commonwealth Building, London, United Kingdom
| | - Waljit S. Dhillo
- Section of Endocrinology and Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Imperial College London at Hammersmith Campus, Commonwealth Building, London, United Kingdom
| | - William H. Colledge
- Reproductive Physiology Group, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
| |
Collapse
|
10
|
Abreu AP, Kaiser UB. Pubertal development and regulation. Lancet Diabetes Endocrinol 2016; 4:254-264. [PMID: 26852256 PMCID: PMC5192018 DOI: 10.1016/s2213-8587(15)00418-0] [Citation(s) in RCA: 269] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 10/22/2015] [Accepted: 10/22/2015] [Indexed: 12/12/2022]
Abstract
Puberty marks the end of childhood and is a period when individuals undergo physiological and psychological changes to achieve sexual maturation and fertility. The hypothalamic-pituitary-gonadal axis controls puberty and reproduction and is tightly regulated by a complex network of excitatory and inhibitory factors. This axis is active in the embryonic and early postnatal stages of life and is subsequently restrained during childhood, and its reactivation culminates in puberty initiation. The mechanisms underlying this reactivation are not completely known. The age of puberty onset varies between individuals and the timing of puberty initiation is associated with several health outcomes in adult life. In this Series paper, we discuss pubertal markers, epidemiological trends of puberty initiation over time, and the mechanisms whereby genetic, metabolic, and other factors control secretion of gonadotropin-releasing hormone to determine initiation of puberty.
Collapse
Affiliation(s)
- Ana Paula Abreu
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Ursula B Kaiser
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
11
|
Zhu HJ, Li SJ, Pan H, Li N, Zhang DX, Wang LJ, Yang HB, Wu Q, Gong FY. The Changes of Serum Leptin and Kisspeptin Levels in Chinese Children and Adolescents in Different Pubertal Stages. Int J Endocrinol 2016; 2016:6790794. [PMID: 27990162 PMCID: PMC5136392 DOI: 10.1155/2016/6790794] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 09/07/2016] [Accepted: 10/11/2016] [Indexed: 11/29/2022] Open
Abstract
The aim of the study is to investigate the changes of serum leptin and kisspeptin levels in children and adolescents with different pubertal stages and nutritional states. A total of 647 Chinese children and adolescents were recruited, and serum estradiol, testosterone, pituitary gonadotropins, leptin, and kisspeptin levels were measured. The results showed that serum leptin levels of boys in T2 stage were the highest among the five stages, while they showed a gradual increase from T1 to T5 stage in girls and reached the highest in T5 stage (P < 0.05). Conversely, serum kisspeptin levels of boys were higher in T4 and T5 stages than those in T1 stage, while its levels of girls were the highest in T2 stage, 21.4% higher than those in T1 stage (P < 0.05). Both leptin and kisspeptin levels were positively correlated with BMI, WC, and weight in all boys and girls (all P < 0.05). In conclusion, kisspeptin levels were firstly found to be notably changed in pubertal stages and nutritional status in Chinese children and adolescents with a significant sexual dimorphism. Obese/overweight girls had higher kisspeptin levels, and there was a positive correlation between kisspeptin and FSH and LH and obesity-related parameters in all boys and girls.
Collapse
Affiliation(s)
- Hui juan Zhu
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Su juan Li
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
- Emergency Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Hui Pan
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Naishi Li
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Dian xi Zhang
- Department of Laboratory Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Lin jie Wang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Hong bo Yang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Qinyong Wu
- Department of Laboratory Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Feng ying Gong
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
- *Feng ying Gong:
| |
Collapse
|
12
|
Maggi R, Cariboni AM, Marelli MM, Moretti RM, Andrè V, Marzagalli M, Limonta P. GnRH and GnRH receptors in the pathophysiology of the human female reproductive system. Hum Reprod Update 2015; 22:358-81. [PMID: 26715597 DOI: 10.1093/humupd/dmv059] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 12/03/2015] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Human reproduction depends on an intact hypothalamic-pituitary-gonadal (HPG) axis. Hypothalamic gonadotrophin-releasing hormone (GnRH) has been recognized, since its identification in 1971, as the central regulator of the production and release of the pituitary gonadotrophins that, in turn, regulate the gonadal functions and the production of sex steroids. The characteristic peculiar development, distribution and episodic activity of GnRH-producing neurons have solicited an interdisciplinary interest on the etiopathogenesis of several reproductive diseases. The more recent identification of a GnRH/GnRH receptor (GnRHR) system in both the human endometrium and ovary has widened the spectrum of action of the peptide and of its analogues beyond its hypothalamic function. METHODS An analysis of research and review articles published in international journals until June 2015 has been carried out to comprehensively summarize both the well established and the most recent knowledge on the physiopathology of the GnRH system in the central and peripheral control of female reproductive functions and diseases. RESULTS This review focuses on the role of GnRH neurons in the control of the reproductive axis. New knowledge is accumulating on the genetic programme that drives GnRH neuron development to ameliorate the diagnosis and treatment of GnRH deficiency and consequent delayed or absent puberty. Moreover, a better understanding of the mechanisms controlling the episodic release of GnRH during the onset of puberty and the ovulatory cycle has enabled the pharmacological use of GnRH itself or its synthetic analogues (agonists and antagonists) to either stimulate or to block the gonadotrophin secretion and modulate the functions of the reproductive axis in several reproductive diseases and in assisted reproduction technology. Several inputs from other neuronal populations, as well as metabolic, somatic and age-related signals, may greatly affect the functions of the GnRH pulse generator during the female lifespan; their modulation may offer new possible strategies for diagnostic and therapeutic interventions. A GnRH/GnRHR system is also expressed in female reproductive tissues (e.g. endometrium and ovary), both in normal and pathological conditions. The expression of this system in the human endometrium and ovary supports its physiological regulatory role in the processes of trophoblast invasion of the maternal endometrium and embryo implantation as well as of follicular development and corpus luteum functions. The GnRH/GnRHR system that is expressed in diseased tissues of the female reproductive tract (both benign and malignant) is at present considered an effective molecular target for the development of novel therapeutic approaches for these pathologies. GnRH agonists are also considered as a promising therapeutic approach to counteract ovarian failure in young female patients undergoing chemotherapy. CONCLUSIONS Increasing knowledge about the regulation of GnRH pulsatile release, as well as the therapeutic use of its analogues, offers interesting new perspectives in the diagnosis, treatment and outcome of female reproductive disorders, including tumoral and iatrogenic diseases.
Collapse
Affiliation(s)
- Roberto Maggi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti, 9, 20133 Milano, Italy
| | - Anna Maria Cariboni
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti, 9, 20133 Milano, Italy
| | - Marina Montagnani Marelli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti, 9, 20133 Milano, Italy
| | - Roberta Manuela Moretti
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti, 9, 20133 Milano, Italy
| | - Valentina Andrè
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti, 9, 20133 Milano, Italy
| | - Monica Marzagalli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti, 9, 20133 Milano, Italy
| | - Patrizia Limonta
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti, 9, 20133 Milano, Italy
| |
Collapse
|
13
|
Millar RP. New Insights into GnRH Neuron Development, Programming and Regulation in Health and Disease. Preface. Neuroendocrinology 2015; 102:181-3. [PMID: 26394199 DOI: 10.1159/000441115] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Robert P Millar
- Centre for Neuroendocrinology and Mammal Research Institute, University of Pretoria, Pretoria, South Africa
| |
Collapse
|
14
|
Choe HK, Chun SK, Kim J, Kim D, Kim HD, Kim K. Real-Time GnRH Gene Transcription in GnRH Promoter-Driven Luciferase-Expressing Transgenic Mice: Effect of Kisspeptin. Neuroendocrinology 2015; 102:194-9. [PMID: 25571901 DOI: 10.1159/000371805] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 12/25/2014] [Indexed: 11/19/2022]
Abstract
Pulsatile secretion of hypothalamic gonadotropin-releasing hormone (GnRH) is indispensable for controlling proper pituitary gonadotrope functions; however, the mechanism underlying GnRH pulse generation remains largely unknown. It is important to understand the cellular oscillator in individual GnRH neurons and temporal synchronization among GnRH neurons. In this brief review, we summarize our recent findings on episodic GnRH gene transcription at the single GnRH neuron level and in synchronized multicellular burst in relation to the temporal pattern of GnRH secretion. We also detail the effects of kisspeptin on ultradian rhythmic GnRH gene transcription and secretion. We extend our discussion to the hierarchical interaction between circadian and ultradian rhythms. Taken together, the current review elucidates the genomic control of GnRH pulse generation in hypothalamic neurons.
Collapse
Affiliation(s)
- Han Kyoung Choe
- Department of Brain and Cognitive Sciences and School of Biological Sciences, Seoul National University, Seoul, South Korea
| | | | | | | | | | | |
Collapse
|