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McCartney CR, Campbell RE, Marshall JC, Moenter SM. The role of gonadotropin-releasing hormone neurons in polycystic ovary syndrome. J Neuroendocrinol 2022; 34:e13093. [PMID: 35083794 PMCID: PMC9232905 DOI: 10.1111/jne.13093] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 12/21/2021] [Accepted: 01/11/2022] [Indexed: 01/28/2023]
Abstract
Given the critical central role of gonadotropin-releasing hormone (GnRH) neurons in fertility, it is not surprising that the GnRH neural network is implicated in the pathology of polycystic ovary syndrome (PCOS), the most common cause of anovulatory infertility. Although many symptoms of PCOS relate most proximately to ovarian dysfunction, the central reproductive neuroendocrine system ultimately drives ovarian function through its regulation of anterior pituitary gonadotropin release. The typical cyclical changes in frequency of GnRH release are often absent in women with PCOS, resulting in a persistent high-frequency drive promoting gonadotropin changes (i.e., relatively high luteinizing hormone and relatively low follicle-stimulating hormone concentrations) that contribute to ovarian hyperandrogenemia and ovulatory dysfunction. However, the specific mechanisms underpinning GnRH neuron dysfunction in PCOS remain unclear. Here, we summarize several preclinical and clinical studies that explore the causes of aberrant GnRH secretion in PCOS and the role of disordered GnRH secretion in PCOS pathophysiology.
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Affiliation(s)
- Christopher R. McCartney
- Center for Research in Reproduction and Department of MedicineUniversity of Virginia School of MedicineCharlottesvilleVAUSA
| | - Rebecca E. Campbell
- Centre for Neuroendocrinology and Department of PhysiologySchool of Biomedical SciencesUniversity of OtagoDunedinNew Zealand
| | - John C. Marshall
- Center for Research in Reproduction and Department of MedicineUniversity of Virginia School of MedicineCharlottesvilleVAUSA
| | - Suzanne M. Moenter
- Departments of Molecular & Integrative PhysiologyInternal MedicineObstetrics and GynecologyUniversity of MichiganAnn ArborMIUSA
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2
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Abstract
The pathophysiology of symptomatic polycystic ovary syndrome (PCOS) often unfolds across puberty, but the ontogeny of PCOS is difficult to study because, in general, its pathophysiology is well entrenched before the diagnosis can be confirmed. However, the study of high-risk groups (daughters of women with PCOS, girls with premature pubarche, and girls with obesity) can offer insight in this regard. Available data support the hypothesis that the pubertal development of PCOS involves various combinations of genetic predisposition, intrauterine programming, hyperinsulinism, and numerous other abnormalities that provoke reproductive symptoms (eg, hyperandrogenism, ovulatory dysfunction) in response to the pubertal increase in gonadotropin secretion.
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Affiliation(s)
- Christine M Burt Solorzano
- Center for Research in Reproduction, University of Virginia School of Medicine, OMS Suhling Building, Room 6921, Hospital Drive, Charlottesville, VA 22908, USA; Department of Pediatrics, Division of Endocrinology and Metabolism, University of Virginia School of Medicine, University of Virginia Health, Box 800386, Charlottesville, VA 22908, USA
| | - Christopher R McCartney
- Center for Research in Reproduction, University of Virginia School of Medicine, OMS Suhling Building, Room 6921, Hospital Drive, Charlottesville, VA 22908, USA; Department of Medicine, Division of Endocrinology and Metabolism, University of Virginia School of Medicine, University of Virginia Health, Box 801406, Charlottesville, VA 22908, USA.
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3
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Burger LL, Wagenmaker ER, Phumsatitpong C, Olson DP, Moenter SM. Prenatal Androgenization Alters the Development of GnRH Neuron and Preoptic Area RNA Transcripts in Female Mice. Endocrinology 2020; 161:5906406. [PMID: 33095238 PMCID: PMC7583650 DOI: 10.1210/endocr/bqaa166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 09/14/2020] [Indexed: 01/27/2023]
Abstract
Polycystic ovary syndrome (PCOS) is the most common form of infertility in women. The causes of PCOS are not yet understood and both genetics and early-life exposure have been considered as candidates. With regard to the latter, circulating androgens are elevated in mid-late gestation in women with PCOS, potentially exposing offspring to elevated androgens in utero; daughters of women with PCOS are at increased risk for developing this disorder. Consistent with these clinical observations, prenatal androgenization (PNA) of several species recapitulates many phenotypes observed in PCOS. There is increasing evidence that symptoms associated with PCOS, including elevated luteinizing hormone (LH) (and presumably gonadotropin-releasing hormone [GnRH]) pulse frequency emerge during the pubertal transition. We utilized translating ribosome affinity purification coupled with ribonucleic acid (RNA) sequencing to examine GnRH neuron messenger RNAs from prepubertal (3 weeks) and adult female control and PNA mice. Prominent in GnRH neurons were transcripts associated with protein synthesis and cellular energetics, in particular oxidative phosphorylation. The GnRH neuron transcript profile was affected more by the transition from prepuberty to adulthood than by PNA treatment; however, PNA did change the developmental trajectory of GnRH neurons. This included families of transcripts related to both protein synthesis and oxidative phosphorylation, which were more prevalent in adults than in prepubertal mice but were blunted in PNA adults. These findings suggest that prenatal androgen exposure can program alterations in the translatome of GnRH neurons, providing a mechanism independent of changes in the genetic code for altered expression.
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Affiliation(s)
- Laura L Burger
- Department of Molecular and Integrative Physiology, Ann Arbor, Michigan
| | | | | | - David P Olson
- Department of Molecular and Integrative Physiology, Ann Arbor, Michigan
- Department of Pediatrics, Ann Arbor, Michigan
| | - Suzanne M Moenter
- Department of Molecular and Integrative Physiology, Ann Arbor, Michigan
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan
- Correspondence: Suzanne M. Moenter; 7725 Med Sci II; 1137 E Catherine St; Ann Arbor, MI 48109-5622, USA. E-mail:
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Santoro M, De Amicis F, Aquila S, Bonofiglio D. Peroxisome proliferator-activated receptor gamma expression along the male genital system and its role in male fertility. Hum Reprod 2020; 35:2072-2085. [PMID: 32766764 DOI: 10.1093/humrep/deaa153] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/28/2020] [Indexed: 12/14/2022] Open
Abstract
Peroxisome proliferator-activated receptor gamma (PPARγ) acts as a ligand activated transcription factor and regulates processes, such as energy homeostasis, cell proliferation and differentiation. PPARγ binds to DNA as a heterodimer with retinoid X receptor and it is activated by polyunsaturated fatty acids and fatty acid derivatives, such as prostaglandins. In addition, the insulin-sensitizing thiazolidinediones, such as rosiglitazone, are potent and specific activators of PPARγ. PPARγ is present along the hypothalamic-pituitary-testis axis and in the testis, where low levels in Leydig cells and higher levels in Sertoli cells as well as in germ cells have been found. High amounts of PPARγ were reported in the normal epididymis and in the prostate, but the receptor was almost undetectable in the seminal vesicles. Interestingly, in the human and in pig, PPARγ protein is highly expressed in ejaculated spermatozoa, suggesting a possible role of PPARγ signaling in the regulation of sperm biology. This implies that both natural and synthetic PPARγ ligands may act directly on sperm improving its performance. Given the close link between energy balance and reproduction, activation of PPARγ may have promising metabolic implications in male reproductive functions. In this review, we first describe PPARγ expression in different compartments of the male reproductive axis. Subsequently, we discuss the role of PPARγ in both physiological and several pathological conditions related to the male fertility.
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Affiliation(s)
- Marta Santoro
- Department of Pharmacy, Health and Nutritional Sciences (Department of Excellence, Italian Law 232/2016), Arcavacata di Rende, Cosenza 87036, Italy.,Centro Sanitario, University of Calabria, Arcavacata di Rende, Cosenza 87036, Italy
| | - Francesca De Amicis
- Department of Pharmacy, Health and Nutritional Sciences (Department of Excellence, Italian Law 232/2016), Arcavacata di Rende, Cosenza 87036, Italy
| | - Saveria Aquila
- Department of Pharmacy, Health and Nutritional Sciences (Department of Excellence, Italian Law 232/2016), Arcavacata di Rende, Cosenza 87036, Italy.,Centro Sanitario, University of Calabria, Arcavacata di Rende, Cosenza 87036, Italy
| | - Daniela Bonofiglio
- Department of Pharmacy, Health and Nutritional Sciences (Department of Excellence, Italian Law 232/2016), Arcavacata di Rende, Cosenza 87036, Italy.,Centro Sanitario, University of Calabria, Arcavacata di Rende, Cosenza 87036, Italy
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Dulka EA, DeFazio RA, Moenter SM. Chemogenetic Suppression of GnRH Neurons during Pubertal Development Can Alter Adult GnRH Neuron Firing Rate and Reproductive Parameters in Female Mice. eNeuro 2020; 7:ENEURO. [PMID: 32513661 DOI: 10.1523/ENEURO.0223-20.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 05/28/2020] [Indexed: 12/02/2022] Open
Abstract
Gonadotropin-releasing hormone (GnRH) neurons control anterior pituitary, and thereby gonadal, function. GnRH neurons are active before outward indicators of puberty appear. Prenatal androgen (PNA) exposure mimics reproductive dysfunction of the common fertility disorder polycystic ovary syndrome (PCOS) and reduces prepubertal GnRH neuron activity. Early neuron activity can play a critical role in establishing circuitry and adult function. We tested the hypothesis that changing prepubertal GnRH neuron activity programs adult GnRH neuron activity and reproduction independent of androgen exposure in female mice. Activating (3Dq) or inhibitory (4Di) designer receptors exclusively activated by designer drugs (DREADDs) were targeted to GnRH neurons using Cre-lox technology. In control studies, the DREADD ligand clozapine n-oxide (CNO) produced the expected changes in GnRH neuron activity in vitro and luteinizing hormone (LH) release in vivo. CNO was administered to control or PNA mice between two and three weeks of age, when GnRH neuron firing rate is reduced in PNA mice. In controls, reducing prepubertal GnRH neuron activity with 4Di increased adult GnRH neuron firing rate and days in diestrus but did not change puberty onset or GABA transmission to these cells. In contrast, activating GnRH neurons had no effect on reproductive parameters or firing rate and did not rescue reproductive phenotypes in PNA mice. These studies support the hypothesis that prepubertal neuronal activity sculpts elements of the adult reproductive neuroendocrine axis and cyclicity but indicate that other PNA-induced programming actions are required for full reproductive phenotypes and/or that compensatory mechanisms overcome activity-mediated changes to mitigate reproductive changes in adults.
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Abstract
Although the fundamental symptoms of polycystic ovary syndrome (PCOS) relate most directly to ovarian dysfunction, central neuroendocrine systems play a prominent role in its pathophysiology. Gonadotropin-releasing hormone (GnRH) pulse generator resistance to negative feedback contributes to rapid GnRH pulse secretion, which promotes gonadotropin abnormalities that foster ovarian hyperandrogenemia and ovulatory dysfunction. The causes of GnRH neuron dysfunction, however, have remained enigmatic. In this review, we highlight a number of recent preclinical and clinical studies pertinent to the neuroendocrine abnormalities of PCOS, including those that have provided important insights into the relevance of animal models with PCOS-like features, the potential roles of kisspeptin and γ-aminobutyric acid (GABA)-ergic neurons, and the potential role of anti-Müllerian hormone.
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Schafer D, Kane G, Colledge WH, Piet R, Herbison AE. Sex- and sub region-dependent modulation of arcuate kisspeptin neurones by vasopressin and vasoactive intestinal peptide. J Neuroendocrinol 2018; 30:e12660. [PMID: 30422333 DOI: 10.1111/jne.12660] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 10/11/2018] [Accepted: 11/07/2018] [Indexed: 02/04/2023]
Abstract
A population of kisspeptin neurones located in the hypothalamic arcuate nucleus (ARN) very likely represent the gonadotrophin-releasing hormone pulse generator responsible for driving pulsatile luteinising hormone secretion in mammals. As such, it has become important to understand the neural inputs that modulate the activity of ARN kisspeptin (ARNKISS ) neurones. Using a transgenic GCaMP6 mouse model allowing the intracellular calcium levels ([Ca2+ ]i ) of individual ARNKISS neurones to be assessed simultaneously, we examined whether the circadian neuropeptides vasoactive intestinal peptide (VIP) and arginine vasopressin (AVP) modulated the activity of ARNKISS neurones directly. To validate this methodology, we initially evaluated the effects of neurokinin B (NKB) on [Ca2+ ]i in kisspeptin neurones residing within the rostral, middle and caudal ARN subregions of adult male and female mice. All experiments were undertaken in the presence of tetrodotoxin and ionotropic amino acid antagonists. NKB was found to evoke an abrupt increase in [Ca2+ ]i in 95%-100% of kisspeptin neurones throughout the ARN of both sexes. By contrast, both VIP and AVP were found to primarily activate kisspeptin neurones located in the caudal ARN of female mice. Although 58% and 59% of caudal ARN kisspeptin neurones responded to AVP and VIP, respectively, in female mice, only 0%-8% of kisspeptin neurones located in other ARN subregions responded in females and 0%-12% of cells in any subregion in males (P < 0.05). These observations demonstrate unexpected sex differences and marked heterogeneity in functional neuropeptide receptor expression amongst ARNKISS neurones organised on a rostro-caudal basis. The functional significance of this unexpected influence of VIP and AVP on ARNKISS neurones remains to be established.
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Affiliation(s)
- Danielle Schafer
- Centre for Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Grace Kane
- Centre for Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - William H Colledge
- Reproductive Physiology Group, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Richard Piet
- Centre for Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Allan E Herbison
- Centre for Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
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Burt Solorzano CM, Knudsen KL, Anderson AD, Hutchens EG, Collins JS, Patrie JT, Marshall JC, McCartney CR. Insulin Resistance, Hyperinsulinemia, and LH: Relative Roles in Peripubertal Obesity-Associated Hyperandrogenemia. J Clin Endocrinol Metab 2018; 103:2571-2582. [PMID: 29897474 PMCID: PMC6692879 DOI: 10.1210/jc.2018-00131] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 04/17/2018] [Indexed: 11/19/2022]
Abstract
CONTEXT Peripubertal obesity is associated with variable hyperandrogenemia, but precise mechanisms remain unclear. OBJECTIVE To assess insulin resistance, hyperinsulinemia, and LH roles in peripubertal obesity-associated hyperandrogenemia. DESIGN Cross-sectional analysis. SETTING Academic clinical research unit. PARTICIPANTS Eleven obese (body mass index for age ≥95%) peripubertal girls. INTERVENTION Blood samples were taken during a mixed-meal tolerance test (1900 to 2100), overnight (2100 to 0700), while fasting (0700 to 0900), and during an 80 mU/m2/min hyperinsulinemic-euglycemic clamp (0900 to 1100). MAIN OUTCOME MEASURES The dependent variable was morning free testosterone level; independent variables were insulin sensitivity index (ISI), estimated 24-hour insulin, and estimated 24-hour LH levels. RESULTS All participants demonstrated insulin resistance and hyperinsulinemia. ISI, but not estimated 24-hour insulin level, correlated positively with morning free testosterone level when correcting for estimated 24-hour LH level and Tanner stage (rs = 0.68, P = 0.046). The correlation between estimated 24-hour LH and free testosterone levels approached significance after adjusting for estimated 24-hour insulin level and Tanner stage (rs = 0.63, P = 0.067). Estimated 24-hour insulin level did not correlate with free testosterone level after adjusting for estimated 24-hour LH level and Tanner stage (rs = 0.47, P = 0.20). CONCLUSION In insulin-resistant obese girls with hyperinsulinemia, free testosterone levels correlated positively with insulin sensitivity and, likely, circulating LH concentrations but not with circulating insulin levels. In the setting of relatively uniform hyperinsulinemia, variable steroidogenic-cell insulin sensitivity may correlate with metabolic insulin sensitivity and contribute to variable free testosterone concentrations.
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Affiliation(s)
- Christine M Burt Solorzano
- Division of Endocrinology, Department of Pediatrics, University of Virginia School of Medicine, Charlottesville, Virginia
- Center for Research in Reproduction, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Karen L Knudsen
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Amy D Anderson
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Eleanor G Hutchens
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Jessicah S Collins
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - James T Patrie
- Department of Public Health Sciences, University of Virginia School of Medicine, Charlottesville, Virginia
| | - John C Marshall
- Center for Research in Reproduction, University of Virginia School of Medicine, Charlottesville, Virginia
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Christopher R McCartney
- Center for Research in Reproduction, University of Virginia School of Medicine, Charlottesville, Virginia
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
- Correspondence and Reprint Requests: Christopher R. McCartney, MD, Center for Research in Reproduction, Box 800391, University of Virginia Health System, Charlottesville, Virginia 22908. E-mail:
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Berg T, Silveira MA, Moenter SM. Prepubertal Development of GABAergic Transmission to Gonadotropin-Releasing Hormone (GnRH) Neurons and Postsynaptic Response Are Altered by Prenatal Androgenization. J Neurosci 2018; 38:2283-93. [PMID: 29374136 DOI: 10.1523/JNEUROSCI.2304-17.2018] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 12/29/2017] [Accepted: 01/20/2018] [Indexed: 11/21/2022] Open
Abstract
Gonadotropin-releasing hormone (GnRH) neurons regulate reproduction through pulsatile GnRH release. Women with polycystic ovary syndrome (PCOS) have persistently elevated luteinizing hormone release frequency, reflecting GnRH release; this exacerbates hyperandrogenemia and disrupted reproductive cycles that are characteristic of this disorder. Clinical evidence suggests that neuroendocrine features of PCOS may manifest peripubertally. Adult mice prenatally exposed to androgens (PNA) mimic several reproductive features of PCOS. GnRH neurons from these mice have increased firing activity and receive increased GABAergic transmission, which is excitatory. When changes emerge during development is unknown. To study the typical postnatal development of GABAergic transmission and the effects of PNA treatment and sex, whole-cell voltage-clamp recordings were made of GABAergic postsynaptic currents (PSCs) in GnRH neurons in brain slices from prepubertal through adult control and PNA female and male mice. GABAergic transmission was present by 1 week of age in females and males and increased in frequency, reaching adult levels at 3 and 4 weeks, respectively. GABAergic PSC frequency was elevated in 3-week-old PNA versus control females. PSC frequency in both controls and PNA mice was activity independent, suggesting that PNA induces changes in synapse organization. PNA also alters the functional response of GnRH neurons to GABA. GABA induced firing in fewer neurons from 3-week-old PNA than control females; membrane potential depolarization induced by GABA was also reduced in cells from PNA mice at this age. PNA thus induces changes during development in the presynaptic organization of the GABAergic network afferent to GnRH neurons as well as the postsynaptic GnRH neuron response, both of which may contribute to adult reproductive dysfunction.SIGNIFICANCE STATEMENT The central neuronal network that regulates reproduction is overactive in polycystic ovary syndrome (PCOS), a leading cause of infertility. Recent evidence of neuroendocrine dysfunction in midpubertal girls suggests that the pathophysiological mechanisms underlying PCOS may arise before pubertal maturation. Prenatal exposure to androgens (PNA) in mice mimics several neuroendocrine features of PCOS. GABAergic transmission to gonadotropin-releasing hormone (GnRH) neurons is important for reproduction and is increased in adult PNA mice. The typical development of this network and when changes with PNA and sex arise relative to puberty are unknown. These studies provide evidence that PNA alters prepubertal development of the GABAergic network afferent to GnRH neurons, including both the presynaptic organization and postsynaptic response. These changes may contribute to reproductive dysfunction in adults.
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Abbott DH, Vepraskas SH, Horton TH, Terasawa E, Levine JE. Accelerated Episodic Luteinizing Hormone Release Accompanies Blunted Progesterone Regulation in PCOS-like Female Rhesus Monkeys (Macaca Mulatta) Exposed to Testosterone during Early-to-Mid Gestation. Neuroendocrinology 2018; 107:133-146. [PMID: 29949806 PMCID: PMC7363207 DOI: 10.1159/000490570] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 06/04/2018] [Indexed: 12/25/2022]
Abstract
BACKGROUND/AIMS Ovarian theca cell hyperandrogenism in women with polycystic ovary syndrome (PCOS) is compounded by androgen receptor-mediated impairment of estradiol and progesterone negative feedback regulation of episodic luteinizing hormone (LH) release. The resultant LH hypersecretion, likely the product of accelerated episodic release of gonadotropin-releasing hormone (GnRH) from the median eminence of the hypothalamus, hyperstimulates ovarian theca cell steroidogenesis, enabling testosterone (T) and androstenedione excess. Prenatally androgenized (PA) female monkeys exposed to fetal male levels of T during early-to-mid gestation, when adult, demonstrate PCOS-like traits, including high T and LH levels. This study tests the hypothesis that progesterone resistance-associated acceleration in episodic LH release contributes to PA monkey LH excess. METHODS A total of 4 PA and 3 regularly cycling, healthy control adult female rhesus monkeys of comparable age and body mass index underwent (1) a 10 h, frequent intravenous sampling assessment for LH episodic release, immediately followed by (2) IV infusion of exogenous GnRH to quantify continuing pituitary LH responsiveness, and subsequently (3) an SC injection of a progesterone receptor antagonist, mifepristone, to examine LH responses to blockade of progesterone-mediated action. RESULTS Compared to controls, the relatively hyperandrogenic PA females exhibited ~100% increase (p = 0.037) in LH pulse frequency, positive correlation of LH pulse amplitude (p = 0.017) with androstenedione, ~100% greater increase (p = 0.034) in acute (0-10 min) LH responses to exogenous GnRH, and an absence (p = 0.008) of modest LH elevation following acute progesterone receptor blockade suggestive of diminished progesterone negative feedback. CONCLUSION Such dysregulation of LH release in PCOS-like monkeys implicates impaired feedback control of episodic release of hypothalamic GnRH reminiscent of PCOS neuroendocrinopathy.
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Affiliation(s)
- David H Abbott
- Department of Obstetrics and Gynecology, University of Wisconsin, Madison, Wisconsin, USA
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin, USA
| | - Sarah H Vepraskas
- Department of Obstetrics and Gynecology, University of Wisconsin, Madison, Wisconsin, USA
| | - Teresa H Horton
- Department of Neurobiology and Physiology, Institute for Neuroscience, Center for Reproductive Science, Northwestern University, Evanston, Illinois, USA
| | - Ei Terasawa
- Department of Pediatrics, University of Wisconsin, Madison, Wisconsin, USA
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin, USA
| | - Jon E Levine
- Department of Neuroscience, University of Wisconsin, Madison, Wisconsin, USA
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin, USA
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11
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Abstract
Gonadotropin-releasing hormone (GnRH) neurons are critical to many aspects of fertility regulation, from producing episodic release critical to both sexes, to providing a central signal to induce the ovulatory cascade in females. This year saw progress through the rejection, and occasional support, of hypotheses in understanding how GnRH neurons contribute to these processes. This brief review provides one laboratory's view of new insights into possible roles for these cells in development, adult reproductive function, and what may go wrong with GnRH neurons in some cases of infertility.
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MESH Headings
- Animals
- Biomedical Research/methods
- Biomedical Research/trends
- Endocrinology/methods
- Endocrinology/trends
- Female
- Gonadotropin-Releasing Hormone/metabolism
- Humans
- Infertility, Female/etiology
- Infertility, Female/pathology
- Infertility, Female/physiopathology
- Infertility, Female/psychology
- Infertility, Male/etiology
- Infertility, Male/pathology
- Infertility, Male/physiopathology
- Infertility, Male/psychology
- Male
- Models, Neurological
- Neurons/cytology
- Neurons/metabolism
- Neurons/pathology
- Neurons/physiology
- Reproducibility of Results
- Reproduction
- Sexual Maturation
- Stress, Physiological
- Stress, Psychological/physiopathology
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Affiliation(s)
- Suzanne M. Moenter
- Departments of Molecular and Integrative Physiology, Internal Medicine, and Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan 48109
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12
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Dulka EA, Moenter SM. Prepubertal Development of Gonadotropin-Releasing Hormone Neuron Activity Is Altered by Sex, Age, and Prenatal Androgen Exposure. Endocrinology 2017; 158:3943-3953. [PMID: 28938422 PMCID: PMC5695838 DOI: 10.1210/en.2017-00768] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Accepted: 09/12/2017] [Indexed: 11/19/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) neurons regulate reproduction though pulsatile hormone release. Disruption of GnRH release as measured via luteinizing hormone (LH) pulses occurs in polycystic ovary syndrome (PCOS), and in young hyperandrogenemic girls. In adult prenatally androgenized (PNA) mice, which exhibit many aspects of PCOS, increased LH is associated with increased GnRH neuron action potential firing. How GnRH neuron activity develops over the prepubertal period and whether this is altered by sex or prenatal androgen treatment are unknown. We hypothesized GnRH neurons are active before puberty and that this activity is sexually differentiated and altered by PNA. Dams were injected with dihydrotestosterone (DHT) on days 16 to 18 post copulation to generate PNA mice. Action potential firing of GFP-identified GnRH neurons in brain slices from 1-, 2-, 3-, and 4-week-old and adult mice was monitored. GnRH neurons were active at all ages tested. In control females, activity increased with age through 3 weeks, then decreased to adult levels. In contrast, activity did not change in PNA females and was reduced at 3 weeks. Activity was higher in control females than males from 2 to 3 weeks. PNA did not affect GnRH neuron firing rate in males at any age. Short-term action potential patterns were also affected by age and PNA treatment. GnRH neurons are thus typically more active during the prepubertal period than adulthood, and PNA reduces prepubertal activity in females. Prepubertal activity may play a role in establishing sexually differentiated neuronal networks upstream of GnRH neurons; androgen-induced changes during this time may contribute to the adult PNA, and possibly PCOS, phenotype.
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Affiliation(s)
- Eden A. Dulka
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109
| | - Suzanne M. Moenter
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan 48109
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Zhao Y, Hou L, Gao HJ, Zhan D, Zhang C, Luo XP. Independent relationship between body mass index and LH peak value of GnRH stimulation test in ICPP girls: A cross-sectional study. ACTA ACUST UNITED AC 2017; 37:556-562. [PMID: 28786058 DOI: 10.1007/s11596-017-1772-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 06/15/2017] [Indexed: 10/18/2022]
Abstract
The effect of obesity on idiopathic central precocious puberty (ICPP) girls is still under discussion. The relationship between body mass index (BMI) and sexual hormone levels of gonadotropin-releasing hormone (GnRH) stimulation test in ICPP girls is controversial and the underlying mechanism is unclear. This study aims to further explore the independent effect of excess adiposity on peak luteinizing hormone (LH) level of stimulation test in ICPP girls and the role of other related factors. A retrospective cross-sectional study was performed on 618 girls diagnosed as having ICPP, including 355 cases of normal weight, 99 cases of overweight and 164 cases of obese. The results showed that obese group had more progressed Tanner stage and no significant difference (P=0.28) in LH peak was found as basal LH value was used as a covariate. The obese group had higher total testosterone (TT), adrenocorticotrophic hormone (ACTH), 17-α hydroxyprogesterone (17-αOHP) and androstendione (AN), with significantly increased fasting insulin (FIN) and homeostasis model of assessment for insulin resistance index (HOMA-IR). Stratified analysis showed inconsistency of the relationship between BMI-standard deviation score (BMI-SDS) and LH peak in different Tanner stages (P for interaction=0.017). Further smoothing plot showed linear and non-linear relationship between BMI-SDS and LH peak in three Tanner stages. Then linear regression model was used to analyze the relationship between BMI-SDS and LH peak in different Tanner stages, with and without different confounding factors being adjusted. In B2 stage, BMI-SDS was negatively associated with LH peak. In B3 stage, when BMI-SDS <1.5, as BMI-SDS increased, the level of LH peak decreased (model I: β=-1.8, 95% CI=-4.7 to 1.1, P=0.214). When BMI-SDS ≥1.5, BMI-SDS was significantly positively associated with LH peak (model I: β=4.5, 95% CI=1.7 to 7.4, P=0.002). In B4 stage, when BMI-SDS <1.5, BMI-SDS was negatively associated with LH peak (model I: β=-11.6, 95% CI=-22.7 to-0.5, P=0.049). When BMI-SDS ≥1.5, BMI-SDS was positively associated with LH peak (model I: β=-4.2, 95% CI=-3.3 to 11.7, P=0.28). It is concluded that there is an independent correlation between BMI-SDS and LH peak of stimulation test in ICPP girls, their relationships are different in different Tanner stages, and the effect of BMI-SDS can be affected by adrenal androgens, estradiol and glucose metabolism parameters.
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Affiliation(s)
- Yue Zhao
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Ling Hou
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hong-Jie Gao
- Department of Pediatrics, Qilu Hospital, Shandong University, Jinan, 250012, China
| | - Di Zhan
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Cai Zhang
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xiao-Ping Luo
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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Lin S, Ji W. Association between insulin resistance and estrogen in sexual precocity of obese children. Exp Ther Med 2016; 12:2497-2500. [PMID: 27703507 PMCID: PMC5038903 DOI: 10.3892/etm.2016.3663] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 06/28/2016] [Indexed: 01/24/2023] Open
Abstract
The aim of the study was to examine the association between sexual precocity and high-molecular weight (HMW)-adiponectin and investigate the correlation of insulin resistance and estrogen levels in obese children. In total, 60 obese children (30 boys and 30 girls) with sexual precocity were included in group A, 60 obese children (30 boys and 30 girls) without sexual precocity were included in group B, and 60 average weight children (30 boys and 30 girls) were included in group C. The levels of HMW adiponectin, fasting blood glucose, fasting insulin, luteinizing hormone (LH) peak, estradiol and testosterone were measured. The results showed that the HMW-adiponectin level of group A was the lowest and that of group C was the highest. The difference was statistically significant (P<0.05). The homeostasis model assessment of insulin resistance (HOMA-IR) and estradiol levels of group A were significantly higher than those of group B, and group B was higher than that of group C. LH peak and testosterone levels of group A were the lowest while those of group C were the highest. The differences were statistically significant (P<0.05). A subgroup analysis showed that the above results were more significant in girls. The Pearson correlation analysis revealed that the level of HMW-adiponectin was negatively correlated with HOMA-IR and estradiol (P<0.05), and positively correlated with the LH peak (P<0.05). In conclusion, sexual precocity of obese children may be associated with insulin resistance, and the link may be HMW-adiponectin.
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Affiliation(s)
- Shixia Lin
- Department of Paediatrics, Jiangyin Hospital Affiliated to Medical School of Southeast University, Jiangyin, Jiangsu 214499, P.R. China; Department of Paediatrics, Children's Hospital Affiliated to Soochow University, Suzhou, Jiangsu 215003, P.R. China
| | - Wei Ji
- Department of Paediatrics, Children's Hospital Affiliated to Soochow University, Suzhou, Jiangsu 215003, P.R. China
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Vitti M, Di Emidio G, Di Carlo M, Carta G, Antonosante A, Artini PG, Cimini A, Tatone C, Benedetti E. Peroxisome Proliferator-Activated Receptors in Female Reproduction and Fertility. PPAR Res 2016; 2016:4612306. [PMID: 27559343 DOI: 10.1155/2016/4612306] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 06/01/2016] [Accepted: 06/19/2016] [Indexed: 12/31/2022] Open
Abstract
Reproductive functions may be altered by the exposure to a multitude of endogenous and exogenous agents, drug or environmental pollutants, which are known to affect gene transcription through the peroxisome proliferator-activated receptors (PPARs) activation. PPARs act as ligand activated transcription factors and regulate metabolic processes such as lipid and glucose metabolism, energy homeostasis, inflammation, and cell proliferation and differentiation. All PPARs isotypes are expressed along the hypothalamic-pituitary-gonadal axis and are strictly involved in reproductive functions. Since female fertility and energy metabolism are tightly interconnected, the research on female infertility points towards the exploration of potential PPARs activating/antagonizing compounds, mainly belonging to the class of thiazolidinediones (TZDs) and fibrates, as useful agents for the maintenance of metabolic homeostasis in women with ovarian dysfunctions. In the present review, we discuss the recent evidence about PPARs expression in the hypothalamic-pituitary-gonadal axis and their involvement in female reproduction. Finally, the therapeutic potential of their manipulation through several drugs is also discussed.
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Abstract
BACKGROUND Acne occurs because the sebaceous glands are overstimulated by high levels of androgens or are hypersensitive to normal levels of testosterone. In women with mild or moderate acne, the association of norgestimate (NG), and ethinyl estradiol (EE) is an effective treatment. This is related to the effect of oral contraceptives on androgen production and transport and the antiandrogenic properties of NG itself. DESIGN The present work was undertaken to find out whether NG and its derivative, 17-deacetylnorgestimate(dNG), present steroid activities other than antiandrogen activities, using human progesterone receptor(PR), estrogen receptor α(ERα) and β(ERβ), glucocorticoid receptor(GR) and mineralocorticoid receptor(MR)-responsive cell lines. RESULTS We confirmed that NG and its metabolite were progestogen partial agonists (EC50 of 13 and 11.1 nM) and ERα selective agonists (EC50 of 30.4 and 43.4 nM), as well as full antagonists of low affinity for GR (IC50 of 325 and 255 nM) and moderate affinity for MR (IC50 of 81.2 and 83.7). CONCLUSION We demonstrated that NG and dNG have full progestogen and weak estrogenic (through ERα) properties, which could explain in part the efficacy of NG in association with EE for the treatment of moderate acne in women. Moreover, their antagonist MR activity might have a favorable impact on cardiovascular risk, atherosclerosis and lipid profiles.
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Affiliation(s)
- Françoise Paris
- INSERM U896, Institut de Recherche en Cancérologie de Montpellier (IRCM) Parc Euromédecine - ICM F-34298 , Montpellier , France
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