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Alternative splicing of the androgen receptor in polycystic ovary syndrome. Proc Natl Acad Sci U S A 2015; 112:4743-8. [PMID: 25825716 DOI: 10.1073/pnas.1418216112] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) is one of the most common female endocrine disorders and a leading cause of female subfertility. The mechanism underlying the pathophysiology of PCOS remains to be illustrated. Here, we identify two alternative splice variants (ASVs) of the androgen receptor (AR), insertion and deletion isoforms, in granulosa cells (GCs) in ∼62% of patients with PCOS. AR ASVs are strongly associated with remarkable hyperandrogenism and abnormalities in folliculogenesis, and are absent from all control subjects without PCOS. Alternative splicing dramatically alters genome-wide AR recruitment and androgen-induced expression of genes related to androgen metabolism and folliculogenesis in human GCs. These findings establish alternative splicing of AR in GCs as the major pathogenic mechanism for hyperandrogenism and abnormal folliculogenesis in PCOS.
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152
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Rivera OE, Varayoud J, Rodríguez HA, Santamaría CG, Bosquiazzo VL, Osti M, Belmonte NM, Muñoz-de-Toro M, Luque EH. Neonatal exposure to xenoestrogens impairs the ovarian response to gonadotropin treatment in lambs. Reproduction 2015; 149:645-55. [PMID: 25778539 DOI: 10.1530/rep-14-0567] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 03/16/2015] [Indexed: 11/08/2022]
Abstract
Bisphenol A (BPA) and diethylstilbestrol (DES) are xenoestrogens, which have been associated with altered effects on reproduction. We hypothesized that neonatal xenoestrogen exposure affects the ovarian functionality in lambs. Thus, we evaluated the ovarian response to exogenous ovine FSH (oFSH) administered from postnatal day 30 (PND30) to PND32 in female lambs previously exposed to low doses of DES or BPA (BPA50: 50 μg/kg per day, BPA0.5: 0.5 μg/kg per day) from PND1 to PND14. We determined: i) follicular growth, ii) circulating levels of 17β-estradiol (E2), iii) steroid receptors (estrogen receptor alpha, estrogen receptor beta, and androgen receptor (AR)) and atresia, and iv) mRNA expression levels of the ovarian bone morphogenetic protein (BMPs) system (BMP6, BMP15, BMPR1B, and GDF9) and FSH receptor (FSHR). Lambs neonatally exposed to DES or BPA showed an impaired ovarian response to oFSH with a lower number of follicles ≥2 mm in diameter together with a lower number of atretic follicles and no increase in E2 serum levels in response to oFSH treatment. In addition, AR induction by oFSH was disrupted in granulosa and theca cells of lambs exposed to DES or BPA. An increase in GDF9 mRNA expression levels was observed in oFSH-primed lambs previously treated with DES or BPA50. In contrast, a decrease in BMPR1B was observed in BPA0.5-postnatally exposed lambs. The modifications in AR, GDF9, and BMPR1B may be associated with the altered ovarian function due to neonatal xenoestrogen exposure in response to an exogenous gonadotropin stimulus. These alterations may be the pathophysiological basis of subfertility syndrome in adulthood.
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Affiliation(s)
- Oscar E Rivera
- Facultad de Ciencias AgrariasUniversidad Nacional de Lomas de Zamora, Buenos Aires, ArgentinaFacultad de Bioquímica y Ciencias BiológicasInstituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral, Casilla de Correo 242, 3000 Santa Fe, Argentina
| | - Jorgelina Varayoud
- Facultad de Ciencias AgrariasUniversidad Nacional de Lomas de Zamora, Buenos Aires, ArgentinaFacultad de Bioquímica y Ciencias BiológicasInstituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral, Casilla de Correo 242, 3000 Santa Fe, Argentina
| | - Horacio A Rodríguez
- Facultad de Ciencias AgrariasUniversidad Nacional de Lomas de Zamora, Buenos Aires, ArgentinaFacultad de Bioquímica y Ciencias BiológicasInstituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral, Casilla de Correo 242, 3000 Santa Fe, Argentina
| | - Clarisa G Santamaría
- Facultad de Ciencias AgrariasUniversidad Nacional de Lomas de Zamora, Buenos Aires, ArgentinaFacultad de Bioquímica y Ciencias BiológicasInstituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral, Casilla de Correo 242, 3000 Santa Fe, Argentina
| | - Verónica L Bosquiazzo
- Facultad de Ciencias AgrariasUniversidad Nacional de Lomas de Zamora, Buenos Aires, ArgentinaFacultad de Bioquímica y Ciencias BiológicasInstituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral, Casilla de Correo 242, 3000 Santa Fe, Argentina
| | - Mario Osti
- Facultad de Ciencias AgrariasUniversidad Nacional de Lomas de Zamora, Buenos Aires, ArgentinaFacultad de Bioquímica y Ciencias BiológicasInstituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral, Casilla de Correo 242, 3000 Santa Fe, Argentina
| | - Norberto M Belmonte
- Facultad de Ciencias AgrariasUniversidad Nacional de Lomas de Zamora, Buenos Aires, ArgentinaFacultad de Bioquímica y Ciencias BiológicasInstituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral, Casilla de Correo 242, 3000 Santa Fe, Argentina
| | - Mónica Muñoz-de-Toro
- Facultad de Ciencias AgrariasUniversidad Nacional de Lomas de Zamora, Buenos Aires, ArgentinaFacultad de Bioquímica y Ciencias BiológicasInstituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral, Casilla de Correo 242, 3000 Santa Fe, Argentina
| | - Enrique H Luque
- Facultad de Ciencias AgrariasUniversidad Nacional de Lomas de Zamora, Buenos Aires, ArgentinaFacultad de Bioquímica y Ciencias BiológicasInstituto de Salud y Ambiente del Litoral (ISAL), Universidad Nacional del Litoral, Casilla de Correo 242, 3000 Santa Fe, Argentina
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153
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Abstract
Although hormonal regulation of ovarian follicle development has been extensively investigated, most studies concentrate on the development of early antral follicles to the preovulatory stage, leading to the successful use of exogenous FSH for infertility treatment. Accumulating data indicate that preantral follicles are under stringent regulation by FSH and local intraovarian factors, thus providing the possibility to develop new therapeutic approaches. Granulosa cell-derived C-type natriuretic factor not only suppresses the final maturation of oocytes to undergo germinal vesicle breakdown before ovulation but also promotes preantral and antral follicle growth. In addition, several oocyte- and granulosa cell-derived factors stimulate preantral follicle growth by acting through wingless, receptor tyrosine kinase, receptor serine kinase, and other signaling pathways. In contrast, the ovarian Hippo signaling pathway constrains follicle growth and disruption of Hippo signaling promotes the secretion of downstream CCN growth factors capable of promoting follicle growth. Although the exact hormonal factors involved in primordial follicle activation has yet to be elucidated, the protein kinase B (AKT) and mammalian target of rapamycin signaling pathways are important for the activation of dormant primordial follicles. Hippo signaling disruption after ovarian fragmentation, combined with treating ovarian fragments with phosphatase and tensin homolog (PTEN) inhibitors and phosphoinositide-3-kinase stimulators to augment AKT signaling, promote the growth of preantral follicles in patients with primary ovarian insufficiency, leading to a new infertility intervention for such patients. Elucidation of intraovarian mechanisms underlying early folliculogenesis may allow the development of novel therapeutic strategies for patients diagnosed with primary ovarian insufficiency, polycystic ovary syndrome, and poor ovarian response to FSH stimulation, as well as for infertile women of advanced reproductive age.
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Affiliation(s)
- Aaron J W Hsueh
- Program of Reproductive and Stem Cell Biology (A.J.W.H., Y.C.), Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, CA 94305-5317; Department of Obstetrics and Gynecology (K.K.), St. Mariana University School of Medicine, Kawasaki, Kanagawa 216-8511, Japan; Department of Reproductive Medicine & Gynecology (B.C.J.M.F.), University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
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154
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Rodrigues JK, Navarro PA, Zelinski MB, Stouffer RL, Xu J. Direct actions of androgens on the survival, growth and secretion of steroids and anti-Müllerian hormone by individual macaque follicles during three-dimensional culture. Hum Reprod 2015; 30:664-74. [PMID: 25567619 DOI: 10.1093/humrep/deu335] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
STUDY QUESTION What are the direct effects of androgens on primate follicular development and function at specific stages of folliculogenesis? SUMMARY ANSWER Androgen addition altered primate follicle survival, growth, steroid and anti-Müllerian hormone (AMH) production, and oocyte quality in vitro, in a dose- and stage-dependent manner. WHAT IS KNOWN ALREADY Androgens have local actions in the ovary, particularly in the developing follicles. It is hypothesized that androgen promotes early follicular growth, but becomes detrimental to the antral follicles in primates. STUDY DESIGN, SIZE, DURATION In vitro follicle maturation was performed using rhesus macaques. Secondary (125-225 µm) follicles were mechanically isolated from 14 pairs of ovaries, encapsulated into alginate (0.25% w/v), and cultured for 40 days. PARTICIPANTS/MATERIALS, SETTING, METHODS Individual follicles were cultured in a 5% O2 environment, in alpha minimum essential medium supplemented with recombinant human FSH. Follicles were randomly assigned to experiments of steroid ablation by trilostane (TRL), testosterone (T) replacement and dihydrotestosterone (DHT) replacement. Follicle survival and growth were assessed. Follicles with diameters ≥500 μm at Week 5 were categorized as fast-grow follicles. Pregnenolone (P5), progesterone (P4), estradiol (E2) and AMH concentrations in media were measured. Meiotic maturation and fertilization of oocytes from recombinant human chorionic gonadotrophin-treated follicles were assessed at the end of culture. MAIN RESULTS AND THE ROLE OF CHANCE Compared with controls, TRL exposure reduced (P < 0.05) follicle survival, antrum formation rate and follicle diameters at Week 5. While P5 concentrations increased (P < 0.05) following TRL treatment, P4 levels decreased (P < 0.05) in fast-grow follicles at Week 5. Few healthy oocytes were retrieved from antral follicles developed in the presence of TRL. T replacement with TRL increased (P < 0.05) follicle survival and antrum formation at Week 5, compared with TRL alone, to levels comparable to controls. However, high-dose T with TRL decreased (P < 0.05) diameters of fast-grow follicles. Although P4 concentrations produced by fast-grow follicles were not altered by T in the presence of TRL, there was a dose-dependent increase (P < 0.05) in E2 levels at Week 5. High-dose T with TRL decreased (P < 0.05) AMH production by fast-grow follicles at Week 3. More healthy oocytes were retrieved from antral follicles developed in TRL+T compared with TRL alone. DHT had the similar effects to those of high-dose T, except that DHT replacement decreased (P < 0.05) E2 concentrations produced by fast-grow follicles at Week 5 regardless of TRL treatment. LIMITATION, REASONS FOR CAUTION This study reports T and DHT actions on in vitro-developed individual primate (macaque) follicles, which are limited to the interval from the secondary to small antral stage. WIDER IMPLICATION OF THE FINDINGS The above findings provide novel information on the role(s) of androgens in primate follicular development and oocyte maturation. We hypothesize that androgens promote pre-antral follicle development, but inhibit antral follicle growth and function in primates. While androgens can act positively, excess levels of androgens may have negative impacts on primate folliculogenesis. STUDY FUNDING/COMPETING INTERESTS NIH U54 RR024347/RL1HD058294/PL1EB008542 (Oncofertility Consortium), NIH U54 HD071836 (SCCPIR), NIH ORWH/NICHD 2K12HD043488 (BIRCWH), NIH FIC TW/HD-00668, ONPRC 8P51OD011092. There are no conflicts of interest.
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Affiliation(s)
- J K Rodrigues
- Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, 505 NW 185th Avenue, Beaverton, OR 97006, USA Department of Gynecology and Obstetrics, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Av. Bandeirantes 3900, Monte Alegre, CEP, 14049, Ribeirão Preto, São Paulo, Brazil Departamento de Pesquisa e Desenvolvimento, Pró-Criar Medicina Reprodutiva, Rua Bernardo Guimarães 2063, Lourdes, 30140, Belo Horizonte, Minas Gerais, Brazil
| | - P A Navarro
- Department of Gynecology and Obstetrics, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Av. Bandeirantes 3900, Monte Alegre, CEP, 14049, Ribeirão Preto, São Paulo, Brazil
| | - M B Zelinski
- Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, 505 NW 185th Avenue, Beaverton, OR 97006, USA Department of Obstetrics & Gynecology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - R L Stouffer
- Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, 505 NW 185th Avenue, Beaverton, OR 97006, USA Department of Obstetrics & Gynecology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - J Xu
- Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, 505 NW 185th Avenue, Beaverton, OR 97006, USA
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155
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Abstract
Although dehydroepiandrosterone (DHEA) and its sulphate ester dehydroepiandrosterone sulphate (DHEAS) are the most abundant steroid hormones in the human circulation, its exact physiological role is not yet fully understood. In patients with adrenal insufficiency, secretion of DHEA is impaired, leading to decreased circulating DHEA and DHEAS levels, and to androgen deficiency in women. Replacement of DHEA in patients with adrenal insufficiency positively influence mood, sexuality and subjective health status. These effects are generally moderate and show high inter-individual variability. Limited evidence exists for immunomodulatory effects of DHEA. Although an increase of IGF-I levels has been documented, relevant effects on body composition, metabolic or cardiovascular parameters has not been observed in patients with adrenal insufficiency receiving DHEA. Larger-scale phase III studies are still lacking; therefore, initiation of DHEA replacement is decided on an individual basis, focussing on those patients with impaired well-being associated with signs and symptoms of androgen deficiency.
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Affiliation(s)
- Katharina Lang
- Endocrinology and Diabetes Unit, Department of Internal Medicine I, University Hospital of Wuerzburg, Oberduerrbacher Strasse 6, D-97080 Wuerzburg, Germany.
| | - Stephanie Burger-Stritt
- Endocrinology and Diabetes Unit, Department of Internal Medicine I, University Hospital of Wuerzburg, Oberduerrbacher Strasse 6, D-97080 Wuerzburg, Germany.
| | - Stefanie Hahner
- Endocrinology and Diabetes Unit, Department of Internal Medicine I, University Hospital of Wuerzburg, Oberduerrbacher Strasse 6, D-97080 Wuerzburg, Germany.
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156
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Liu Z, Hao C, Song D, Zhang N, Bao H, Qu Q. Androgen Receptor Coregulator CTBP1-AS Is Associated With Polycystic Ovary Syndrome in Chinese Women: A Preliminary Study. Reprod Sci 2014; 22:829-37. [PMID: 25552498 DOI: 10.1177/1933719114565037] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Polycystic ovary syndrome (PCOS) is currently considered a predominantly hyperandrogenic syndrome. In theory, hyperandrogenism can be caused by high level of testosterone (T) as well as by enhanced androgen receptor (AR) activity. C-Terminal binding protein 1 antisense (CTBP1-AS) was a novel long noncoding RNA (lncRNA) to regulate AR activity. In this study, we found that expression level of CTBP1-AS in peripheral blood leukocytes was significantly higher in women with PCOS than that in controls after adjustment for age and body mass index (BMI). Individuals having higher expression of CTBP1-AS had significantly greater disease risk than those having lower expression. We also identified expression of CTBP1-AS as an independent risk factor for PCOS. A positive correlation was observed between the CTBP1-AS expression and the total T (TT) concentration either unadjusted or after adjusting for age, BMI, and homeostatic model assessment insulin resistance. Taken together, our current study presented the first evidence that the lncRNA CTBP1-AS, a novel AR modulator, is associated with PCOS in Chinese population and established the possibility that abnormal CTBP1-AS expression is a risk factor for PCOS and it is a predictor of variability in serum TT level in Chinese women with PCOS.
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Affiliation(s)
- Zhenteng Liu
- Medical College of Qingdao University, Qingdao, China Department of Reproductive Medicine, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College of Qingdao University, Yantai, Shandong, China
| | - Cuifang Hao
- Department of Reproductive Medicine, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College of Qingdao University, Yantai, Shandong, China
| | - Dehua Song
- Department of Reproductive Medicine, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College of Qingdao University, Yantai, Shandong, China
| | - Ning Zhang
- Department of Reproductive Medicine, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College of Qingdao University, Yantai, Shandong, China
| | - Hongchu Bao
- Department of Reproductive Medicine, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College of Qingdao University, Yantai, Shandong, China
| | - Qinglan Qu
- Department of Reproductive Medicine, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College of Qingdao University, Yantai, Shandong, China
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157
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Abstract
Rhythmic events in the female reproductive system depend on the coordinated and synchronized activity of multiple neuroendocrine and endocrine tissues. This coordination is facilitated by the timing of gene expression and cellular physiology at each level of the hypothalamo-pituitary-ovarian (HPO) axis, including the basal hypothalamus and forebrain, the pituitary gland, and the ovary. Central to this pathway is the primary circadian pacemaker in the suprachiasmatic nucleus (SCN) that, through its myriad outputs, provides a temporal framework for gonadotropin release and ovulation. The heart of the timing system, a transcription-based oscillator, imparts SCN pacemaker cells and a company of peripheral tissues with the capacity for daily oscillations of gene expression and cellular physiology. Although the SCN sits comfortably at the helm, peripheral oscillators (such as the ovary) have undefined but potentially critical roles. Each cell type of the ovary, including theca cells, granulosa cells, and oocytes, harbor a molecular clock implicated in the processes of follicular growth, steroid hormone synthesis, and ovulation. The ovarian clock is influenced by the reproductive cycle and diseases that perturb the cycle and/or follicular growth can disrupt the timing of clock gene expression in the ovary. Chronodisruption is known to negatively affect reproductive function and fertility in both rodent models and women exposed to shiftwork schedules. Thus, influencing clock function in the HPO axis with chronobiotics may represent a novel avenue for the treatment of common fertility disorders, particularly those resulting from chronic circadian disruption.
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Affiliation(s)
- Michael T. Sellix
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
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158
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Zhang HH, Xu PY, Wu J, Zou WW, Xu XM, Cao XY, Wei LZ. Dehydroepiandrosterone improves follicular fluid bone morphogenetic protein-15 and accumulated embryo score of infertility patients with diminished ovarian reserve undergoing in vitro fertilization: a randomized controlled trial. J Ovarian Res 2014; 7:93. [PMID: 25330837 PMCID: PMC4210503 DOI: 10.1186/s13048-014-0093-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 09/30/2014] [Indexed: 12/02/2022] Open
Abstract
Objective To evaluate the effect of dehydroepiandrosterone (DHEA) on infertility patients with diminished ovarian reserve undergoing in vitro fertilization. Methods This is a prospective study. Ninety-five patients with diminished ovarian reserve were included in this study. Of them, 42 patients were randomly allocated to the DHEA group, who received DHEA 75 mg daily for three consecutive menstrual cycles prior to IVF cycles, and 53 patients were allocated to the control group, who entered IVF cycles directly. All patients were treated with the same ovarian stimulation protocol. Follicular fluid samples from both groups were collected for bone morphogenetic protein-15 (BMP-15) and growth differentiation factor-9 (GDF-9). Fluid from the first aspirated follicle without any visible blood contamination was carefully collected. In addition, day 3 Blood samples were collected pre- and post-treatment of DHEA for serum anti-Mullerian hormone (AMH), follicle stimulating hormone (FSH) and estradiol (E2) in the DHEA group. Results The level of BMP-15 in follicular fluid samples from the DHEA group was significantly higher than that of the control samples (P=.000). Patients after DHEA treatment demonstrated a significantly higher level of AMH and a significantly lower level of FSH, E2 compared to themselves prior to DHEA therapy (P=.015; P=.036; P=.002; respectively). Moreover, the accumulated score of embryos was significantly higher in the DHEA group (P=.033). Conclusions These observations confirm the beneficial effect of DHEA for infertility patients with diminished ovarian reserve. Trial registration ChiCTR-TRC-14005002
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Affiliation(s)
| | | | | | | | | | | | - Lian Z Wei
- Department of Reproductive Endocrinology, the Reproductive Medicine Center, The Affiliated Hospital of Anhui Medical University, Anhui, People's Republic of China.
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159
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Lledó B, Llácer J, Turienzo A, Ortiz JA, Guerrero J, Morales R, Ten J, Bernabeu R. Androgen receptor CAG repeat length is associated with ovarian reserve but not with ovarian response. Reprod Biomed Online 2014; 29:509-15. [DOI: 10.1016/j.rbmo.2014.06.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 06/19/2014] [Accepted: 06/23/2014] [Indexed: 10/25/2022]
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160
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Abstract
For many decades, elevated androgens in women have been associated with poor reproductive health. However, recent studies have shown that androgens play a crucial role in women's fertility. The following review provides an overall perspective about how androgens and androgen receptor-mediated actions regulate normal follicular development, as well as discuss emerging concepts, latest perceptions, and controversies regarding androgen actions and signaling in the ovary.
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Affiliation(s)
- Hen Prizant
- Division of Endocrinology and MetabolismDepartment of Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, PO Box 693, Rochester, New York 14642, USACenter for Human ReproductionNew York, New York 10021, USA
| | - Norbert Gleicher
- Division of Endocrinology and MetabolismDepartment of Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, PO Box 693, Rochester, New York 14642, USACenter for Human ReproductionNew York, New York 10021, USA
| | - Aritro Sen
- Division of Endocrinology and MetabolismDepartment of Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, PO Box 693, Rochester, New York 14642, USACenter for Human ReproductionNew York, New York 10021, USADivision of Endocrinology and MetabolismDepartment of Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, PO Box 693, Rochester, New York 14642, USACenter for Human ReproductionNew York, New York 10021, USA
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161
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Wu S, Chen Y, Fajobi T, DiVall SA, Chang C, Yeh S, Wolfe A. Conditional knockout of the androgen receptor in gonadotropes reveals crucial roles for androgen in gonadotropin synthesis and surge in female mice. Mol Endocrinol 2014; 28:1670-81. [PMID: 25157703 DOI: 10.1210/me.2014-1154] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Polycystic ovary syndrome is the major cause of infertility in reproductive aged women. Polycystic ovary syndrome is associated with high circulating levels of androgens and impaired metabolic function. The goal of this study was to understand how androgen signaling via the androgen receptor (AR) affects reproductive function. We knocked out the AR gene specifically in pituitary gonadotropes (PitARKO) to explore the role of androgen on the development of reproductive function in female mice. There was no difference in the age of puberty between control and PitARKO littermates, which was assessed by the ages of vaginal opening and first estrus. Cyclicity and fertility were also studied, and there was no significant difference between control and PitARKO mice. We observed a significant decrease in basal FSH serum and mRNA levels with no corresponding change in LH serum and mRNA levels. Although the numbers of litters born to control and PitARKO females were the same, the litter size was significantly smaller for PitARKO mice. The LH and FSH responses to ovariectomy was altered with reduced LH/FSH hormone and mRNA levels in PitARKO females. This reduction may be due to reduced expression of activin A/B and gnrhr. The preovulatory surge levels of LH and FSH were dramatically lower in PitARKO mice. The number of corpora lutea was decreased whereas the number of antral follicles was similar between control and PitARKO mice. Overall the pituitary AR contributes to the elaboration of the LH surge and normal reproductive function by regulating LH/FSH expression and secretion.
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Affiliation(s)
- Sheng Wu
- Pediatrics Department (S.W., Y.C., T.F., S.A.D., A.W.), Johns Hopkins School of Medicine, Baltimore, Maryland 21286; Department of Pathology and Laboratory Medicine (C.C.), University of Rochester Medical Center, Rochester, New York 14642; and Department of Urology and Pathology (S.Y.), University of Rochester, Rochester, New York 14642
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162
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LH pretreatment as a novel strategy for poor responders. BIOMED RESEARCH INTERNATIONAL 2014; 2014:926172. [PMID: 25197669 PMCID: PMC4145542 DOI: 10.1155/2014/926172] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 07/18/2014] [Accepted: 07/30/2014] [Indexed: 11/23/2022]
Abstract
Introduction. Poor response to ovarian stimulation is still a major problem in IVF. The study presents a new stimulation protocol evaluated in a suppopulation of very difficult young poor ovarian responders. Material and Methods. The study consists in two sections. The first includes data from a randomized controlled study involving forty-three young patients with a poor ovarian response in at least two previous cycles (intended as cycle cancellation or with ≤3 collected oocytes). Patients were randomized in two groups: group A (control) received FSH (400 IU/day), while group B received the new stimulation protocol consisting in a sequential association of 150 IU r-LH for 4 days followed by 400 IU r-FSH/after downregulation with daily GnRh agonist. The second includes data from the overall results in 65 patients treated with the new protocol compared to their previous performance with conventional cycles (historical control). Results. Both in the RCT and in the historical control study, LH pretreatment was able to decrease the cancellation rate, to improve the in vitro performance, and to significantly increase the live birth rates. Conclusions. LH pretreatment improved oocyte quantity and quality in young repeated poor responders selected in accordance with the Bologna criteria.
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163
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Gleicher N, Barad DH, Kushnir VA, Sen A, Weghofer A. Poor responders and androgen adjuvant treatment: "Still haven't found what I'm looking for …". Reprod Biomed Online 2014; 29:650-2. [PMID: 25246123 DOI: 10.1016/j.rbmo.2014.07.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 07/09/2014] [Accepted: 07/24/2014] [Indexed: 12/23/2022]
Affiliation(s)
| | - David H Barad
- The Center for Human Reproduction, New York, NY, USA; Foundation for Reproductive Medicine, New York, NY, USA
| | | | - Aritro Sen
- Division of Medical Endocrinology and Metabolism, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Andrea Weghofer
- Department of Obstetrics and Gynecology, Vienna University School of Medicine, Vienna, Austria
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164
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Barad DH, Kushnir VA, Lee HJ, Lazzaroni E, Gleicher N. Effect of inter-cycle interval on oocyte production in humans in the presence of the weak androgen DHEA and follicle stimulating hormone: a case-control study. Reprod Biol Endocrinol 2014; 12:68. [PMID: 25048047 PMCID: PMC4123494 DOI: 10.1186/1477-7827-12-68] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 06/27/2014] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND In various animal models androgens have been demonstrated to enhance follicle stimulating hormone (FSH) activity on granulosa cells during small growing follicle stages. To assess whether similar synergism may also exist in humans we investigated women on androgen (dehydroepiandrosterone, DHEA) supplementation with varying concomitant FSH exposure. METHODS In a case controlled cohort study we determine if time interval between IVF cycles of IVF treatment with FSH had an effect on ovarian response to ovulation induction in women supplemented with DHEA. Among 85 women with known low functional ovarian reserve (LFOR), supplemented with DHEA, and undergoing at least 3 consecutive IVF cycles, 68 demonstrated short (<120 days) intervals between repeated cycles (Group 1) and were, therefore, considered to have consistent FSH exposure. In contrast 17 women (Group 2) demonstrated long (>=120 days) intervals between repeated cycles and, therefore, were considered to demonstrate inconsistent FSH exposure. Trends in oocyte yields were compared between these groups, utilizing mixed model repeated measures ANOVA, adjusted for initial age and FSH dose. RESULTS Only women in Group I demonstrated a linear increase in oocyte yields across their three cycles of treatments (F=7.92; df 1, 68.6; p=0.017). Moreover, the analysis revealed a significant interaction between the two patient groups and cycle number for retrieved oocytes (F=6.32, df=2, 85.9, p=0.003). CONCLUSIONS This study offers preliminary confirmatory evidence that repeated short interval exposure to androgens in combination with FSH improves human FOR. A higher level of evidence will require prospectively randomized studies.
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Affiliation(s)
- David H Barad
- The Center for Human Reproduction, 21 East 69th St, New York, New York, USA
- Foundation for Reproductive Medicine, New York, New York, USA
| | - Vitaly A Kushnir
- The Center for Human Reproduction, 21 East 69th St, New York, New York, USA
| | - Ho-Joon Lee
- The Center for Human Reproduction, 21 East 69th St, New York, New York, USA
| | - Emanuela Lazzaroni
- The Center for Human Reproduction, 21 East 69th St, New York, New York, USA
| | - Norbert Gleicher
- The Center for Human Reproduction, 21 East 69th St, New York, New York, USA
- Foundation for Reproductive Medicine, New York, New York, USA
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Gleicher N, Kushnir VA, Weghofer A, Barad DH. The "graying" of infertility services: an impending revolution nobody is ready for. Reprod Biol Endocrinol 2014; 12:63. [PMID: 25012752 PMCID: PMC4105876 DOI: 10.1186/1477-7827-12-63] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 07/06/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND As demand for infertility services by older women continues to grow, because achievable in vitro fertilization (IVF) outcomes are widely underestimated, most fertility centers do not offer maximal treatment options with use of autologous oocytes. Limited data suggest that clinical IVF outcomes in excess of what the American Society for Reproductive Medicine (ASRM) considers "futile" can, likely, be achieved up to at least age 45 years. METHODS In an attempt to point out an evolving demographic trend in IVF, we here report our center's IVF data for 2010-2012 and national U.S. data for 1997-2010. Though our center's data are representative of only one IVF center's patients, they, likely, are unique since they probably represent the most adversely selected IVF patient population ever reported and, thus, are predictive of future demographic trends. In addition we performed a systematic review of the literature on the subject based on PubMed, Medline and Google Scholar searches till year-end 2013. The literature search was performed using key words and phrases relevant to fertility treatments in older women. RESULTS As demonstrated by our center's patient demographics and national U.S. data, IVF centers are destined to treat increasingly adversely selected patients. Despite our center's already extremely adversely selected patient population, age-specific IVF cycle outcomes in women above age 40 years, nevertheless, exceeded criteria for "futility" by the ASRM and widely quoted outcome expectations in the literature for patient ages. Age 43 discriminates between better and poorer clinical pregnancy and live birth rates. CONCLUSIONS "Graying" of the infertility populations in the developed world, a problem with potentially far-reaching medical and societal consequences, has so far been only insufficiently addressed in the literature. As women's postmenopausal life spans already exceed postmenarcheal life spans at the start of the 20th century, the "graying" of infertility services can be expected to further accelerate, no longer as in recent decades bringing only women in their 40s into maternity wards but also women in their 50s and 60s. Medicine and society better get ready for this revolution.
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Affiliation(s)
- Norbert Gleicher
- Center for Human Reproduction, New York, NY 10021, USA
- Foundation for Reproductive Medicine, New York, NY 10021, USA
| | | | - Andrea Weghofer
- Center for Human Reproduction, New York, NY 10021, USA
- Department of Gynecologic Endocrinology and Reproductive Medicine, Medical University Vienna, Vienna 1090, Austria
| | - David H Barad
- Center for Human Reproduction, New York, NY 10021, USA
- Foundation for Reproductive Medicine, New York, NY 10021, USA
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A randomized, controlled, pilot trial on the effect of dehydroepiandrosterone on ovarian response markers, ovarian response, and in vitro fertilization outcomes in poor responders. Fertil Steril 2014; 102:108-115.e1. [DOI: 10.1016/j.fertnstert.2014.03.044] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 03/12/2014] [Accepted: 03/14/2014] [Indexed: 11/19/2022]
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Xu B, Li Z, Yue J, Jin L, Li Y, Ai J, Zhang H, Zhu G. Effect of dehydroepiandrosterone administration in patients with poor ovarian response according to the Bologna criteria. PLoS One 2014; 9:e99858. [PMID: 24932478 PMCID: PMC4059703 DOI: 10.1371/journal.pone.0099858] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 05/16/2014] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Dehydroepiandrosterone (DHEA) is now widely used as an adjuvant to IVF treatment protocols in poor responders. However, clinical evidence for DHEA on improvement of ovarian response and IVF outcome is still limited, the validity of the results of the earlier studies, especially the varied inclusion criteria, is a subject of debate. Recently, the ESHRE Working Group developed a new definition, the Bologna criteria. The aim of the current study was to investigate the potential effect of DHEA treatment on in vitro fertilization (IVF) outcome of poor ovarian responders that fulfill the Bologna criteria. METHODS This study investigated 386 poor ovarian responders that fulfill the Bologna criteria. Patients underwent IVF-ET treatment with the GnRH antagonist protocol. The study group contained 189 patients, who received 75 mg of DHEA daily (25 mg three times daily) before the IVF cycle. The control group was composed of 197 patients who received infertility treatment, but did not receive DHEA. The IVF outcome parameters in each group were compared. RESULTS The study and control groups did not show statistically significant differences in terms of patient demographics characteristics, mean numbers of oocytes retrieved, mature oocytes, fertilization rate, cleavage rate, or embryo availability. While the DHEA group demonstrated significantly higher implantation rates (18.7% vs. 10.1%; P<0.01) and ongoing PRs (26.7% vs. 15.8%; P<0.05) as compared with the control. CONCLUSIONS DHEA pre-treatment does not significantly increase oocyte yield. However, the ongoing PRs in this subgroup of women are significantly higher after DHEA administration, suggesting that DHEA may increase IVF results by improving oocyte and embryo quality.
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Affiliation(s)
- Bei Xu
- Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Zhou Li
- Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Jing Yue
- Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Lei Jin
- Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Yufeng Li
- Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Jihui Ai
- Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Hanwang Zhang
- Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Guijin Zhu
- Reproductive Medicine Center, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
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Sun B, Wang F, Sun J, Yu W, Sun Y. Basal serum testosterone levels correlate with ovarian response but do not predict pregnancy outcome in non-PCOS women undergoing IVF. J Assist Reprod Genet 2014; 31:829-35. [PMID: 24849376 DOI: 10.1007/s10815-014-0246-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 05/05/2014] [Indexed: 01/13/2023] Open
Abstract
PURPOSE To evaluate basal testosterone (T) levels in women undergoing in vitro fertilization (IVF) cycles and examine the association between basal T levels and ovarian response or IVF pregnancy outcome. METHODS We retrospectively analyzed 1413 infertile Chinese women undergoing their first IVF treatment at our institution's reproductive center from March 2011 to May 2013. The basal testosterone (T) levels in women undergoing in vitro fertilization (IVF) and the relationship between basal T levels and ovarian response or IVF pregnancy outcome were determined. These patients did not have polycystic ovary syndrome (PCOS) or endometriosis, and were treated with a long luteal down-regulation protocol. Subjects were divided into 2 groups according to basal testosterone (T) levels: Group 1, basal T values <20 ng/dl (n = 473), and Group 2, basal T values >20 ng/dl (n = 940). We evaluated the association of basal T levels with ovarian response and IVF outcome in the two groups. RESULTS In this study, BMI, basal follicle-stimulating hormone (FSH) levels, basal luteinizing hormone (LH) levels, antral follicle count (AFC), days of stimulation, total gonadotrophin dose, basal FSH/LH ratio, and the number of follicles >14 mm were significantly different (P < 0.05) between the two groups. Basal T level positively correlated with ovarian reserve function, number of follicles >14 mm on human chorionic gonadotrophin (HCG) day, and total gonadotropin dose. However, basal T levels play no role in predicting IVF pregnancy outcome. CONCLUSION Basal T level can be used as a good predictor for ovarian response and the number of large follicles on HCG day. Additionally, we may use basal T level as a marker to predict FSH dosage. In general women, lower level of T might relate with potential poor ovarian response. However, based on our data, basal T levels do not predict pregnancy outcome.
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Affiliation(s)
- Bo Sun
- Reproductive Medical Center, First Affiliated Hospital of Zhengzhou University, Henan, China
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169
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The role of androgen hormones in early follicular development. ISRN OBSTETRICS AND GYNECOLOGY 2014; 2014:818010. [PMID: 25006485 PMCID: PMC4003798 DOI: 10.1155/2014/818010] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 02/18/2014] [Indexed: 11/17/2022]
Abstract
Background. Although chronic hyperandrogenism, a typical feature of polycystic ovary syndrome, is often associated with disturbed reproductive performance, androgens have been shown to promote ovarian follicle growth in shorter exposures. Here, we review the main effects of androgens on the regulation of early folliculogenesis and the potential of their application in improving follicular in vitro growth. Review. Androgens may affect folliculogenesis directly via androgen receptors (ARs) or indirectly through aromatization to estrogen. ARs are highly expressed in the granulosa and theca cells of early stage follicles and slightly expressed in mature follicles. Short-term androgen exposure augments FSH receptor expression in the granulosa cells of developing follicles and enhances the FSH-induced cAMP formation necessary for the transcription of genes involved in the control of follicular cell proliferation and differentiation. AR activation also increases insulin-like growth factor (IGF-1) and its receptor gene expression in the granulosa and theca cells of growing follicles and in the oocytes of primordial follicles, thus facilitating IGF-1 actions in both follicular recruitment and subsequent development. Conclusion. During the early and intermediate stages of follicular maturation, locally produced androgens facilitate the transition of follicles from the dormant to the growing pool as well as their further development.
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Abstract
BACKGROUND Understanding the physiology of pregnancy enables effective management of pregnancy complications that could otherwise be life threatening for both mother and fetus. A functional uterus (i) retains the fetus in utero during pregnancy without initiating stretch-induced contractions and (ii) is able to dilate the cervix and contract the myometrium at term to deliver the fetus. The onset of labour is associated with successful cervical remodelling and contraction of myometrium, arising from concomitant activation of uterine immune and endocrine systems. A large body of evidence suggests that actions of local steroid hormones may drive changes occurring in the uterine microenvironment at term. Although there have been a number of studies considering the potential role(s) played by progesterone and estrogen at the time of parturition, the bio-availability and effects of androgens during pregnancy have received less scrutiny. The aim of this review is to highlight potential roles of androgens in the biology of pregnancy and parturition. METHODS A review of published literature was performed to address (i) androgen concentrations, including biosynthesis and clearance, in maternal and fetal compartments throughout gestation, (ii) associations of androgen concentrations with adverse pregnancy outcomes, (iii) the role of androgens in the physiology of cervical remodelling and finally (iv) the role of androgens in the physiology of myometrial function including any impact on contractility. RESULTS Some, but not all, androgens increase throughout gestation in maternal circulation. The effects of this increase are not fully understood; however, evidence suggests that increased androgens might regulate key processes during pregnancy and parturition. For example, androgens are believed to be critical for cervical remodelling at term, in particular cervical ripening, via regulation of cervical collagen fibril organization. Additionally, a number of studies highlight potential roles for androgens in myometrial relaxation via non-genomic, AR-independent pathways critical for the pregnancy reaching term. Understanding of the molecular events leading to myometrial relaxation is an important step towards development of novel targeted tocolytic drugs. CONCLUSIONS The increase in androgen levels throughout gestation is likely to be important for establishment and maintenance of pregnancy and initiation of parturition. Further investigation of the underlying mechanisms of androgen action on cervical remodelling and myometrial contractility is needed. The insights gained may facilitate the development of new therapeutic approaches to manage pregnancy complications such as preterm birth.
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Affiliation(s)
- Sofia Makieva
- Medical Research Council Centre for Reproductive Health, The University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, United Kingdom and Tommy's Centre for Maternal and Fetal Health, University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, United Kingdom
| | - Philippa T K Saunders
- Medical Research Council Centre for Reproductive Health, The University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, United Kingdom and
| | - Jane E Norman
- Medical Research Council Centre for Reproductive Health, The University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, United Kingdom and Tommy's Centre for Maternal and Fetal Health, University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, United Kingdom
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171
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Nozawa K, Nagaoka K, Zhang H, Usuda K, Okazaki S, Taya K, Yoshida M, Watanabe G. Neonatal exposure to 17α-ethynyl estradiol affects ovarian gene expression and disrupts reproductive cycles in female rats. Reprod Toxicol 2014; 46:77-84. [PMID: 24632129 DOI: 10.1016/j.reprotox.2014.03.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 02/27/2014] [Accepted: 03/03/2014] [Indexed: 01/10/2023]
Abstract
Neonatal exposure to synthetic estrogen causes delayed reproductive dysfunction in female rats. Exposure to 17α-ethynyl estradiol (EE, low: 20 and high: 2000 μg/kg) induced an abnormal estrous cycle during PND171-190 in low-dose and PND126-145 in high-dose group. At PND90 within normal estrous cycle, high-dose animals showed lack of LH surge and low of ovarian hormones in serum level. Gene expression analysis demonstrated that level of mRNA encoding luteinizing hormone/chorionic gonadotropin receptor (LHCGR) was higher in EE-treated ovaries than in control ovaries, and LHCGR protein colocalized with apoptosis-related proteins in the interstitial area of the ovary. At PND1, ovarian LHCGR mRNA levels were higher in EE-treated rats than in control rats, and direct induction of LHCGR expression by EE was observed in vitro. Our results indicate that neonatal exposure to EE induces irregular LHCGR expression in the immature ovary, which may influence the occurrence of delayed reproductive dysfunction in adult animals.
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Affiliation(s)
- Kaori Nozawa
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Kentaro Nagaoka
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan.
| | - Haolin Zhang
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Kento Usuda
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Sachiko Okazaki
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Kazuyoshi Taya
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Midori Yoshida
- Division of Pathology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan
| | - Gen Watanabe
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
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172
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Androgens regulate ovarian follicular development by increasing follicle stimulating hormone receptor and microRNA-125b expression. Proc Natl Acad Sci U S A 2014; 111:3008-13. [PMID: 24516121 DOI: 10.1073/pnas.1318978111] [Citation(s) in RCA: 208] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Although androgen excess is considered detrimental to women's health and fertility, global and ovarian granulosa cell-specific androgen-receptor (AR) knockout mouse models have been used to show that androgen actions through ARs are actually necessary for normal ovarian function and female fertility. Here we describe two AR-mediated pathways in granulosa cells that regulate ovarian follicular development and therefore female fertility. First, we show that androgens attenuate follicular atresia through nuclear and extranuclear signaling pathways by enhancing expression of the microRNA (miR) miR-125b, which in turn suppresses proapoptotic protein expression. Second, we demonstrate that, independent of transcription, androgens enhance follicle-stimulating hormone (FSH) receptor expression, which then augments FSH-mediated follicle growth and development. Interestingly, we find that the scaffold molecule paxillin regulates both processes, making it a critical regulator of AR actions in the ovary. Finally, we report that low doses of exogenous androgens enhance gonadotropin-induced ovulation in mice, further demonstrating the critical role that androgens play in follicular development and fertility. These data may explain reported positive effects of androgens on ovulation rates in women with diminished ovarian reserve. Furthermore, this study demonstrates mechanisms that might contribute to the unregulated follicle growth seen in diseases of excess androgens such as polycystic ovary syndrome.
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173
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Alebić MŠ, Stojanović N. Dehydroepiandrostendione sulphate and prediction of live birth after IVF in young women with low anti-Müllerian hormone concentration. Reprod Biomed Online 2014; 28:191-7. [DOI: 10.1016/j.rbmo.2013.09.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 06/26/2013] [Accepted: 09/24/2013] [Indexed: 12/01/2022]
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Abstract
An increasing body of evidence suggests that immune-mediated processes affect female reproductive success at multiple levels. Crosstalk between endocrine and immune systems regulates a large number of biological processes that affect target tissues, and this crosstalk involves gene expression, cytokine and/or lymphokine release and hormone action. In addition, endocrine-immune interactions have a major role in the implantation process of the fetal (paternally derived) semi-allograft, which requires a reprogramming process of the maternal immune system from rejection to temporary tolerance for the length of gestation. Usually, the female immune system is supportive of all of these processes and, therefore, facilitates reproductive success. Abnormalities of the female immune system, including autoimmunity, potentially interfere at multiple levels. The relevance of the immune system to female infertility is increasingly recognized by investigators, but clinically is often not adequately considered and is, therefore, underestimated. This Review summarizes the effect of individual autoimmune endocrine diseases on female fertility, and points towards selected developments expected in the near future.
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Affiliation(s)
- Aritro Sen
- The Center for Human Reproduction (CHR), 21 East 69th Street, New York, NY 10021, USA
| | - Vitaly A Kushnir
- The Center for Human Reproduction (CHR), 21 East 69th Street, New York, NY 10021, USA
| | - David H Barad
- The Center for Human Reproduction (CHR), 21 East 69th Street, New York, NY 10021, USA
| | - Norbert Gleicher
- The Center for Human Reproduction (CHR), 21 East 69th Street, New York, NY 10021, USA
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Bonnet A, Cabau C, Bouchez O, Sarry J, Marsaud N, Foissac S, Woloszyn F, Mulsant P, Mandon-Pepin B. An overview of gene expression dynamics during early ovarian folliculogenesis: specificity of follicular compartments and bi-directional dialog. BMC Genomics 2013; 14:904. [PMID: 24350644 PMCID: PMC3890531 DOI: 10.1186/1471-2164-14-904] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 12/10/2013] [Indexed: 12/03/2022] Open
Abstract
Background Successful early folliculogenesis is crucial for female reproductive function. It requires appropriate gene specific expression of the different types of ovarian cells at different developmental stages. To date, most gene expression studies on the ovary were conducted in rodents and did not distinguish the type of cell. In mono-ovulating species, few studies have addressed gene expression profiles and mainly concerned human oocytes. Results We used a laser capture microdissection method combined with RNA-seq technology to explore the transcriptome in oocytes and granulosa cells (GCs) during development of the sheep ovarian follicle. We first documented the expression profile of 15 349 genes, then focused on the 5 129 genes showing differential expression between oocytes and GCs. Enriched functional categories such as oocyte meiotic arrest and GC steroid synthesis reflect two distinct cell fates. We identified the implication of GC signal transduction pathways such as SHH, WNT and RHO GTPase. In addition, signaling pathways (VEGF, NOTCH, IGF1, etc.) and GC transzonal projections suggest the existence of complex cell-cell interactions. Finally, we highlighted several transcription regulators and specifically expressed genes that likely play an important role in early folliculogenesis. Conclusions To our knowledge, this is the first comprehensive exploration of transcriptomes derived from in vivo oocytes and GCs at key stages in early follicular development in sheep. Collectively, our data advance our understanding of early folliculogenesis in mono-ovulating species and will be a valuable resource for unraveling human ovarian dysfunction such as premature ovarian failure (POF).
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Affiliation(s)
- Agnes Bonnet
- INRA, UMR444 Génétique Cellulaire, Auzeville, BP52627, F-31326, Castanet-Tolosan, France.
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Androgens and the androgen receptor (AR). Mol Oncol 2013. [DOI: 10.1017/cbo9781139046947.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Yang M, Du J, Lu D, Ren C, Shen H, Qiao J, Chen X, Zhang H. Increased expression of kindlin 2 in luteinized granulosa cells correlates with androgen receptor level in patients with polycystic ovary syndrome having hyperandrogenemia. Reprod Sci 2013; 21:696-703. [PMID: 24336678 DOI: 10.1177/1933719113512536] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Hyperandrogenemia is the leading defect in patients with polycystic ovary syndrome (PCOS) and considered to be involved in the ovulation dysfunction of PCOS. During the process of ovulation, granulosa cells (GCs) undergo epithelial-mesenchymal transition (EMT), and integrin-interacting protein kindlin 2 is a well-known regulator in EMT. Therefore, our objective here was to compare the expression levels of kindlin 2 in luteinized GCs between patients with PCOS and control women and the relationship between kindlin 2 and PCOS pathogenesis. In this study, kindlin 2 expression was significantly increased in luteinized GCs from patients with PCOS, and kindlin 2 could be induced by testosterone both in vitro and in vivo. Meanwhile, kindlin 2 was positively correlated with androgen receptor (AR) in PCOS GCs. Taken together, kindlin 2 may play a role in luteinized GCs, especially in the case of excess androgen. Further studies are required to assess the specific role of kindlin 2 in follicular development and PCOS pathogenesis.
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Affiliation(s)
- Mei Yang
- 1Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, and Laboratory of Stem Cell, Development and Reproductive Medicine, Department of Anatomy, Histology and Embryology, Peking University Health Science Center, Beijing, China
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Lebbe M, Woodruff T. Involvement of androgens in ovarian health and disease. Mol Hum Reprod 2013; 19:828-37. [PMID: 24026057 PMCID: PMC3843026 DOI: 10.1093/molehr/gat065] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 09/04/2013] [Accepted: 09/05/2013] [Indexed: 11/13/2022] Open
Abstract
In women, ovary and adrenal gland produce androgens. Androgens are essential drivers of the primordial to antral follicle development, prior to serving as substrate for estrogen production in the later stages of folliculogenesis. Androgens play a crucial role in the follicular-stromal intertalk by fine tuning the extracellular matrix and vessel content of the ovarian stroma. Local auto-and paracrine factors regulate androgen synthesis in the pre-antral follicle. Androgen excess is a hallmark of polycystic ovary syndrome and is a key contributor in the exaggerated antral follicle formation, stromal hyperplasia and hypervascularity. Hyperandrogenaemia overrides the follicular-stromal dialog, resulting in follicular arrest and disturbed ovulation. On the other hand, androgen deficiency is likely to have a negative impact on fertility as well, and further research is needed to examine the benefits of androgen-replacement therapy in subfertility.
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Affiliation(s)
- M. Lebbe
- Centre for Endocrinology, Diabetes and Metabolism (CEDAM), School of Clinical & Experimental Medicine, University of Birmingham, Birmingham B15 2TT, UK
| | - T.K. Woodruff
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E Superior Street, Lurie 10-121, Chicago, IL 60610, USA
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Gleicher N, Kushnir VA, Barad DH. Therapeutic interventions into early stages of follicle maturation: a new treatment paradigm after over 50 years of modern infertility therapy. Endocrinology 2013; 154:3498-501. [PMID: 24058156 DOI: 10.1210/en.2013-1679] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Norbert Gleicher
- MD, The Center for Human Reproduction-New York, 21 East 69th Street, New York, New York 10021.
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181
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Dart DA, Waxman J, Aboagye EO, Bevan CL. Visualising androgen receptor activity in male and female mice. PLoS One 2013; 8:e71694. [PMID: 23940781 PMCID: PMC3737126 DOI: 10.1371/journal.pone.0071694] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 07/08/2013] [Indexed: 11/19/2022] Open
Abstract
Androgens, required for normal development and fertility of males and females, have vital roles in the reproductive tract, brain, cardiovascular system, smooth muscle and bone. Androgens function via the androgen receptor (AR), a ligand-dependent transcription factor. To assay and localise AR activity in vivo we generated the transgenic “ARE-Luc” mouse, expressing a luciferase reporter gene under the control of activated endogenous AR. In vivo imaging of androgen-mediated luciferase activity revealed several strongly expressing tissues in the male mouse as expected and also in certain female tissues. In males the testes, prostate, seminal vesicles and bone marrow all showed high AR activity. In females, strong activity was seen in the ovaries, uterus, omentum tissue and mammary glands. In both sexes AR expression and activity was also found in salivary glands, the eye (and associated glands), adipose tissue, spleen and, notably, regions of the brain. Luciferase protein expression was found in the same cell layers as androgen receptor expression. Additionally, mouse AR expression and activity correlated well with AR expression in human tissues. The anti-androgen bicalutamide reduced luciferase signal in all tissues. Our model demonstrates that androgens can act in these tissues directly via AR, rather than exclusively via androgen aromatisation to estrogens and activation of the estrogen receptor. Additionally, it visually demonstrates the fundamental importance of AR signalling outside the normal role in the reproductive organs. This model represents an important tool for physiological and developmental analysis of androgen signalling, and for characterization of known and novel androgenic or antiandrogenic compounds.
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Affiliation(s)
- D. Alwyn Dart
- Department of Surgery & Cancer, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom
| | - Jonathan Waxman
- Department of Surgery & Cancer, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom
| | - Eric O. Aboagye
- Department of Surgery & Cancer, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom
| | - Charlotte L. Bevan
- Department of Surgery & Cancer, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom
- * E-mail:
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182
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Orisaka M, Hattori K, Fukuda S, Mizutani T, Miyamoto K, Sato T, Tsang BK, Kotsuji F, Yoshida Y. Dysregulation of ovarian follicular development in female rat: LH decreases FSH sensitivity during preantral-early antral transition. Endocrinology 2013; 154:2870-80. [PMID: 23709086 DOI: 10.1210/en.2012-2173] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Several clinical studies have shown a correlation of hypersecretion of LH and polycystic ovary syndrome (PCOS), infertility, and miscarriage in women, suggesting that chronically elevated LH impairs fertility. Growth arrest of small antral follicles in PCOS is also assumed to be associated with an abnormal endocrine environment involving increased LH stimulation, a hyperandrogenic milieu, and subsequent dysregulated FSH action in the ovarian follicles. In this study, we examined whether and how LH modulates follicular development and steroid production during preantral-early antral follicle transition by using a rat preantral follicle culture system. LH augments testosterone and estradiol production in preantral follicles via up-regulating mRNA abundance of CYP17A1 and CYP19A1. LH promotes rat preantral follicle growth, and the follicular size reaches that of early antral follicles in vitro, a response attenuated by the specific androgen receptor antagonist and a targeted disruption of androgen receptor gene. Sustained follicle stimulation by LH, but not by androgen, decreases FSH receptor mRNA levels and FSH receptor signaling and inhibits FSH-induced follicular growth. The data suggest that LH promotes preantral-early antral transition via the increased synthesis and growth-promoting action of androgen. However, chronic LH stimulation impairs FSH-dependent antral follicle growth by suppressing granulosa cell FSHR expression via the modulation of intraovarian regulators, including LH-induced thecal factors.
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Affiliation(s)
- Makoto Orisaka
- Department of Obstetrics and Gynecology, University of Fukui, Fukui, Japan 910-1193.
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183
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Chang C, Lee SO, Wang RS, Yeh S, Chang TM. Androgen receptor (AR) physiological roles in male and female reproductive systems: lessons learned from AR-knockout mice lacking AR in selective cells. Biol Reprod 2013; 89:21. [PMID: 23782840 DOI: 10.1095/biolreprod.113.109132] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Androgens/androgen receptor (AR) signaling is involved primarily in the development of male-specific phenotypes during embryogenesis, spermatogenesis, sexual behavior, and fertility during adult life. However, this signaling has also been shown to play an important role in development of female reproductive organs and their functions, such as ovarian folliculogenesis, embryonic implantation, and uterine and breast development. The establishment of the testicular feminization (Tfm) mouse model exploiting the X-linked Tfm mutation in mice has been a good in vivo tool for studying the human complete androgen insensitivity syndrome, but this mouse may not be the perfect in vivo model. Mouse models with various cell-specific AR knockout (ARKO) might allow us to study AR roles in individual types of cells in these male and female reproductive systems, although discrepancies are found in results between labs, probably due to using various Cre mice and/or knocking out AR in different AR domains. Nevertheless, no doubt exists that the continuous development of these ARKO mouse models and careful studies will provide information useful for understanding AR roles in reproductive systems of humans and may help us to develop more effective and more specific therapeutic approaches for reproductive system-related diseases.
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Affiliation(s)
- Chawnshang Chang
- George Whipple Lab for Cancer Research, Departments of Pathology, Urology, and Radiation Oncology, University of Rochester Medical Center, Rochester, NY, USA.
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184
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Gleicher N, Weghofer A, Kushnir VA, Shohat-Tal A, Lazzaroni E, Lee HJ, Barad DH. Is androgen production in association with immune system activation potential evidence for existence of a functional adrenal/ovarian autoimmune system in women? Reprod Biol Endocrinol 2013; 11:58. [PMID: 23805952 PMCID: PMC3700837 DOI: 10.1186/1477-7827-11-58] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 06/24/2013] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Low functional ovarian reserve (FOR) is at all ages associated with low testosterone (T) levels. Causes are, however, unknown. We, therefore, investigate whether androgens with low FOR are associated with non-specific immune system activation. METHODS 322 infertile women with low and normal FOR (controls) were assessed with a broadly based immune profile, which in previous studies has proven effective in differentiating infertile patients with and without immune system activation. Patients were either immune-positive (greater than or equal to one positive tested parameter) or immune negative (no positive test). 135 suffered from prematurely diminished FOR (POA/OPOI; < age 38), 155 from physiologic diminished FOR due to age (DOR; > age 40), and 32 were controls (< age 38 with normal age-specific FOR). Prevalence of immune-positive vs. negative was assessed in all 3 patient groups. RESULTS Women with immune abnormalities, overall, demonstrated higher total T (TT, P = 0.004) and free T (FT, P < 0.001) levels than those without. The three clinical and two immunologic-defined patient groups demonstrated significant statistical interaction in mean TT (P = 0.008), with mean TT and FT in women with positive immune findings being significantly higher in control than in POA/OPOI and physiologic DOR patients (all 4 differences P < 0.001). No such differences between the three groups were seen in women without immune abnormalities. CONCLUSIONS In this study we used a definition of immune-positivity, which favors sensitivity over specificity, resulting in significant numbers of false-positives but likely only few false-negatives. The study allows suggesting the possibility of an immune system-derived androgen-production factor (APF), which maintains normal androgen levels but is deficient in women with low FOR and immune system inactivity. Existence of such an APF would suggest the presence of a still unknown functional adrenal autoimmune system.
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Affiliation(s)
- Norbert Gleicher
- Center for Human Reproduction, New York, NY 10021, USA
- Foundation for Reproductive Medicine, New York, NY 10021, USA
| | - Andrea Weghofer
- Center for Human Reproduction, New York, NY 10021, USA
- Department of Gynecologic Endocrinology and Reproductive Medicine, Medical University Vienna, Vienna 1090, Austria
| | | | | | | | - Ho-Joon Lee
- Center for Human Reproduction, New York, NY 10021, USA
| | - David H Barad
- Center for Human Reproduction, New York, NY 10021, USA
- Foundation for Reproductive Medicine, New York, NY 10021, USA
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185
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Fouany MR, Sharara FI. Is there a role for DHEA supplementation in women with diminished ovarian reserve? J Assist Reprod Genet 2013; 30:1239-44. [PMID: 23737215 DOI: 10.1007/s10815-013-0018-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 05/17/2013] [Indexed: 01/27/2023] Open
Abstract
PURPOSE Poor ovarian reserve and poor ovarian response presents a challenge to IVF centers. Dehydroepiandrosterone (DHEA) supplementation is increasingly being used by many IVF centers around the world in poor responders despite the lack of convincing data. We therefore examined the rationale for the use of DHEA in poor responders, address the relevant studies, present new data, and address its potential mechanisms of action. METHODS All published articles on the role of DHEA in infertile women from 1990 to April 2013 were reviewed. RESULTS Several studies have suggested an improvement in pregnancy rates with the use of DHEA. Potential mechanisms include improved follicular steroidogenesis, increased IGF-1, acting as a pre-hormone for follicular testosterone, reducing aneuploidy, and increasing AMH and antral follicle count. While the role of DHEA is intriguing, evidence-based recommendations are lacking. CONCLUSIONS While nearly 25 % of IVF programs use DHEA currently, large randomized prospective trials are sorely needed. Until (and if) such trials are conducted, DHEA may be of benefit in suitable, well informed, and consented women with diminished ovarian reserve.
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Affiliation(s)
- Mazen R Fouany
- Department of Obstetrics and Gynecology, Charles Cole Memorial Hospital, Coudersport, PA, USA
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186
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Testosterone-dependent interaction between androgen receptor and aryl hydrocarbon receptor induces liver receptor homolog 1 expression in rat granulosa cells. Mol Cell Biol 2013; 33:2817-28. [PMID: 23689136 DOI: 10.1128/mcb.00011-13] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Androgens play a major role in the regulation of normal ovarian function; however, they are also involved in the development of ovarian pathologies. These contrasting effects may involve a differential response of granulosa cells to the androgens testosterone (T) and dihydrotestosterone (DHT). To determine the molecular pathways that mediate the distinct effects of T and DHT, we studied the expression of the liver receptor homolog 1 (LRH-1) gene, which is differentially regulated by these steroids. We found that although both T and DHT stimulate androgen receptor (AR) binding to the LRH-1 promoter, DHT prevents T-mediated stimulation of LRH-1 expression. T stimulated the expression of aryl hydrocarbon receptor (AHR) and its interaction with the AR. T also promoted the recruitment of the AR/AHR complex to the LRH-1 promoter. These effects were not mimicked by DHT. We also observed that the activation of extracellular regulated kinases by T is required for AR and AHR interaction. In summary, T, but not DHT, stimulates AHR expression and the interaction between AHR and AR, leading to the stimulation of LRH-1 expression. These findings could explain the distinct response of granulosa cells to T and DHT and provide a molecular mechanism by which DHT negatively affects ovarian function.
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187
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Yazawa T, Kawabe S, Kanno M, Mizutani T, Imamichi Y, Ju Y, Matsumura T, Yamazaki Y, Usami Y, Kuribayashi M, Shimada M, Kitano T, Umezawa A, Miyamoto K. Androgen/androgen receptor pathway regulates expression of the genes for cyclooxygenase-2 and amphiregulin in periovulatory granulosa cells. Mol Cell Endocrinol 2013; 369:42-51. [PMID: 23415714 DOI: 10.1016/j.mce.2013.02.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 12/26/2012] [Accepted: 02/05/2013] [Indexed: 01/30/2023]
Abstract
It is well known that the androgen/androgen receptor (AR) pathway is involved in both male and female fertility in mammals. AR knockout female mice are reported to exhibit various abnormalities in follicle development, and a subfertile phenotype. In exogenous gonadotropin-induced superovulation, serum androgen levels were robustly elevated in female mice at the periovulatory stage after human chorionic gonadotropin (hCG) treatment. At this stage, ovarian AR proteins were strongly expressed in cumulus cells. Because these results suggested that the androgen/AR pathway is involved in ovulation, we investigated the expression of ovulation-related genes in the mouse ovary treated with the nonaromatizable androgen, 5α-dihydrotestosterone (DHT). DHT treatment induced the expression of the genes for cyclooxyganase-2 (Cox-2 or prostaglandin endoperoxidase synthase 2) and the epidermal growth factor-like factor, amphiregulin (Areg), in the ovary, whereas their hCG-induced expression was suppressed by the AR antagonist flutamide. These genes were also induced by DHT in AR-expressing primary granulosa and granulosa tumor-derived cells. Reporter assays, electrophoretic shift mobility assays and chromatin immunoprecipitation assays demonstrated that androgen response sequence(s) existing upstream of each gene were responsible for androgen responsiveness and were occupied by the AR in periovulatory granulosa cells. Our results suggest that the androgen/AR pathway is involved in the ovulatory process via expression of the Cox-2 and Areg genes in periovulatory granulosa cells.
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Affiliation(s)
- Takashi Yazawa
- Department of Biochemistry, Faculty of Medical Sciences, University of Fukui, Matsuoka, Fukui, Japan.
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188
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Sellix MT, Murphy ZC, Menaker M. Excess androgen during puberty disrupts circadian organization in female rats. Endocrinology 2013; 154:1636-47. [PMID: 23417420 PMCID: PMC3602624 DOI: 10.1210/en.2012-2066] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Circadian clocks have been described in each tissue of the hypothalamo-pituitary-ovarian axis. Although a role for the clock in the timing of ovulation is indicated, the impact of diseases that disrupt fertility on clock function or the clocks' role in the etiology of these pathologies has yet to be fully appreciated. Polycystic ovary syndrome (PCOS) is a particularly devastating endocrinopathy, affecting approximately 10% of women at childbearing age. Common features of PCOS are a polycystic ovary, amenorrhea, and excess serum androgen. Approximately 40% of these women have metabolic syndrome, including hyperinsulinemia, dyslipidemia, and hyperleptinemia. It has been suggested that excess androgen is a critical factor in the etiology of PCOS. We have examined the effects of androgen excess during puberty on the phase of circadian clocks in tissues of the metabolic and hypothalamo-pituitary-ovarian axes. Female period1-luciferase (per1-luc) rats were exposed to androgen (5α-dihydrotestosterone [DHT]) or placebo for 4-6 weeks (short term) or 9-15 weeks (long term). As expected, DHT-treated animals gained more weight than controls and had disrupted estrous cycles. At the end of treatment, tissues, including the liver, lung, kidney, white adipose, cornea, pituitary, oviduct, and ovarian follicles, were cultured, and per1-luc expression in each was recorded. Analysis of per1-luc expression revealed that DHT exposure increased phase distribution of multiple oscillators, including ovarian follicles, liver, and adipose, and altered phase synchrony between animals. These data suggest that excess androgen during puberty, a common feature of PCOS, negatively affects internal circadian organization in both the reproductive and metabolic axes.
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Affiliation(s)
- Michael T Sellix
- Department of Medicine, Division of Endocrinology and Metabolism, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Box 693, Rochester, New York 14642, USA.
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189
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Dumesic DA, Richards JS. Ontogeny of the ovary in polycystic ovary syndrome. Fertil Steril 2013; 100:23-38. [PMID: 23472949 DOI: 10.1016/j.fertnstert.2013.02.011] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 02/05/2013] [Accepted: 02/06/2013] [Indexed: 12/11/2022]
Abstract
Activation of primordial follicles into the growing pool, selection of the dominant follicle, and its eventual ovulation require complex endocrine and metabolic interactions as well as intraovarian paracrine signals to coordinate granulosa cell proliferation, theca cell differentiation, and oocyte maturation. Early preantral follicle development relies mostly upon mesenchymal-epithelial cell interactions, intraovarian paracrine signals, and oocyte-secreted factors, whereas development of the antral follicle depends on circulating gonadotropins as well as locally derived regulators. In women with polycystic ovary syndrome (PCOS), ovarian hyperandrogenism, hyperinsulinemia from insulin resistance, and altered intrafollicular paracrine signaling perturb the activation, survival, growth, and selection of follicles, causing accumulation of small antral follicles within the periphery of the ovary, giving it a polycystic morphology. Altered adipocyte-ovarian interactions further compound these adverse events on follicle development and also can harm the oocyte, particularly in the presence of increased adiposity. Finally, endocrine antecedents of PCOS occur in female infants born to mothers with PCOS, which suggests that interactions between genes and the maternal-fetal hormonal environment may program ovarian function after birth.
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Affiliation(s)
- Daniel A Dumesic
- Department of Obstetrics and Gynecology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA.
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190
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Gleicher N, Kim A, Weghofer A, Kushnir VA, Shohat-Tal A, Lazzaroni E, Lee HJ, Barad DH. Hypoandrogenism in association with diminished functional ovarian reserve. Hum Reprod 2013; 28:1084-91. [DOI: 10.1093/humrep/det033] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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191
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Butler MS, Yang X, Ricciardelli C, Liang X, Norman RJ, Tilley WD, Hickey TE. Small glutamine-rich tetratricopeptide repeat-containing protein alpha is present in human ovaries but may not be differentially expressed in relation to polycystic ovary syndrome. Fertil Steril 2013; 99:2076-83.e1. [PMID: 23433514 DOI: 10.1016/j.fertnstert.2013.01.140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 01/25/2013] [Accepted: 01/25/2013] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To evaluate the expression and function of small glutamine-rich tetratricopeptide repeat-containing protein alpha (SGTA), an androgen receptor (AR) molecular chaperone, in human ovarian tissues. DESIGN Examine the effect of SGTA on AR subcellular localization in granulosa tumor cells (KGN) and SGTA expression in ovarian tissues. SETTING University-based research laboratory. PATIENT(S) Archived tissues from premenopausal women and granulosa cells from infertile women receiving assisted reproduction. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) AR subcellular localization and SGTA protein or mRNA levels. RESULT(S) SGTA and AR proteins were expressed in the cytoplasm of KGN cells and exposure to androgen stimulated AR nuclear localization. SGTA protein knockdown increased AR nuclear localization at low (0-0.1 nmol/L) but not high (1-10 nmol/L) concentrations of androgen hormone. In ovarian tissues, SGTA was localized to the cytoplasm of granulosa cells at all stages of folliculogenesis and in thecal cells of antral follicles. SGTA protein levels were similar when comparing primordial and primary follicles within core biopsies (n = 40) from women with and without polycystic ovary syndrome (PCOS). Likewise, SGTA mRNA levels were not significantly different in granulosa cells from preovulatory follicles after hyperstimulation of women with and without PCOS. CONCLUSION(S) SGTA is present in human ovaries and has the potential to modulate AR signalling, but it may not be differentially expressed in PCOS.
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Affiliation(s)
- Miriam S Butler
- Dame Roma Mitchell Cancer Research Laboratories, School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
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192
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Tsuji I, Ami K, Fujinami N. Pregnancy following ovarian induction in a patient with premature ovarian failure and undetectable serum anti-Müllerian hormone. J Obstet Gynaecol Res 2013; 39:1070-2. [DOI: 10.1111/j.1447-0756.2012.02068.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 09/19/2012] [Indexed: 11/26/2022]
Affiliation(s)
- Isao Tsuji
- Department of Obstetrics and Gynecology; Kinki University Faculty of Medicine; Osaka; Japan
| | - Kazumi Ami
- Department of Obstetrics and Gynecology; Kinki University Faculty of Medicine; Osaka; Japan
| | - Nahoko Fujinami
- Department of Obstetrics and Gynecology; Kinki University Faculty of Medicine; Osaka; Japan
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193
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Dorward AM, Yaskowiak ES, Smith KN, Stanford KR, Shultz KL, Beamer WG. Chromosome X loci and spontaneous granulosa cell tumor development in SWR mice: epigenetics and epistasis at work for an ovarian phenotype. Epigenetics 2013; 8:184-91. [PMID: 23299801 PMCID: PMC3592904 DOI: 10.4161/epi.23399] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Females of the SWR/Bm (SWR) inbred mouse strain possess a unique susceptibility to juvenile-onset tumors originating from the granulosa cells (GC) of the ovarian follicles. Tumor susceptibility is an inherited, polygenic trait in SWR females, minimally involving an oncogenic Granulosa cell tumor susceptibility (Gct) locus on chromosome (Chr) 4 (Gct1), and two GC tumor susceptibility modifier genes mapped to distinct regions of Chr X (Gct4 and Gct6). Shifts in the frequency of GC tumor initiation in the SWR female population from low penetrance to moderate penetrance, or phenotype switching between GC tumor-susceptible and GC tumor-resistant, is strongly influenced by the allelic contributions at Gct4 and Gct6. In addition to the allele-specific effects, GC tumor susceptibility is controlled by the mode of X-linked transmission with a dominant, paternal parent-of-origin effect. We took advantage of the robust paternal effect with a recombinant male progeny testing strategy to resolve the Gct4 locus interval to 1.345 million base (Mb) pairs. Based on the mapping resolution and the phenotype sensitivity to endogenous and exogenous androgen exposure, a promising candidate for Gct4 identity is the androgen receptor (Ar) gene. We explored the mechanism of allelic variation for Ar between SWR (low penetrance allele) and SJL/Bm (SJL) (moderate penetrance allele) using an SWR.SJL-X congenic strain resource and a quantitative gene expression method. We report the low GC tumor penetrance allele of the SWR strain correlates with significantly reduced Ar transcript levels in the female ovary at the pubertal transition.
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Affiliation(s)
- Ann M Dorward
- Division of BioMedical Sciences, Memorial University of Newfoundland, St. John's, NL, Canada.
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194
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Morohashi K, Baba T, Tanaka M. Steroid Hormones and the Development of Reproductive Organs. Sex Dev 2013; 7:61-79. [DOI: 10.1159/000342272] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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195
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Walters KA, Middleton LJ, Joseph SR, Hazra R, Jimenez M, Simanainen U, Allan CM, Handelsman DJ. Targeted loss of androgen receptor signaling in murine granulosa cells of preantral and antral follicles causes female subfertility. Biol Reprod 2012; 87:151. [PMID: 23115271 DOI: 10.1095/biolreprod.112.102012] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Ovarian granulosa cells display strong androgen receptor (AR) expression, suggesting a functional role for direct AR-mediated actions within developing mammalian follicles. By crossing AR-floxed and anti-Müllerian hormone (AMH)-Cre recombinase mice, we generated granulosa cell-specific androgen receptor knockout mice (GCARKO). Cre expression, assessed by lacZ activity, localized to 70%-100% of granulosa cells in most preantral to antral follicles, allowing for selected evaluation of granulosa cell AR-dependent actions during follicle development. Relative to wild-type (WT) females, GCARKO females were subfertile, producing a 24% reduction in the number of litters (P < 0.05) over 6 mo and an age-dependent decrease in total number of pups born, evident from 6 mo of age (P < 0.05). Follicle dynamics were altered in GCARKO ovaries at 3 mo of age, with a significant reduction in large preantral and small antral follicle numbers compared to WT ovaries (P < 0.05). Global premature follicle depletion was not observed, but increased follicular atresia was evident in GCARKO ovaries at 6 mo of age, with an 81% increase in unhealthy follicles and zona pellucida remnants (P < 0.01). Cumulus cell expansion was decreased (P < 0.01) and oocyte viability was diminished in GCARKO females, with a significant reduction in the percentage of oocytes fertilized after natural mating and, thus, in the rate of progression to the two-cell embryo stage (P < 0.05). In addition, compared with age-matched WT females, 6-mo-old GCARKO females exhibited significantly prolonged estrous cycles (P ≤ 0.05), suggesting altered hypothalamic-pituitary-gonadal feedback signaling. In conclusion, our findings revealed that selective loss of granulosa cell AR actions during preantral and antral stages of development leads to a premature reduction in female fecundity through reduced follicle health and oocyte viability.
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Affiliation(s)
- Kirsty A Walters
- ANZAC Research Institute, Department of Andrology, Concord Hospital, University of Sydney, Sydney, New South Wales, Australia.
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196
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Gleicher N, Kim A, Weghofer A, Shohat-Tal A, Lazzaroni E, Lee HJ, Barad DH. Starting and resulting testosterone levels after androgen supplementation determine at all ages in vitro fertilization (IVF) pregnancy rates in women with diminished ovarian reserve (DOR). J Assist Reprod Genet 2012; 30:49-62. [PMID: 23212832 DOI: 10.1007/s10815-012-9890-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 11/04/2012] [Indexed: 10/27/2022] Open
Abstract
PURPOSE To investigate whether androgen conversion rates after supplementation with dehydroepiandrosterone (DHEA) differ, and whether differences between patients with diminished ovarian reserve (DOR) are predictive of pregnancy chances in association with in vitro fertilization (IVF). METHODS In a prospective cohort study we investigated 213 women with DOR, stratified for age (≤ 38 or >38 years) and ovarian FMR1 genotypes/sub-genotypes. All women were for at least 6 weeks supplemented with 75 mg of DHEA daily prior to IVF, between initial presentation and start of 1st IVF cycles. Levels of DHEA, DHEA-sulfate (DHEAS), total T (TT) and free T (FT) at baseline ((BL)) and IVF cycle start ((CS)) were then compared between conception and non-conception cycles. RESULTS Mean age for the study population was 41.5 ± 4.4 years. Forty-seven IVF cycles (22.1 %) resulted in clinical pregnancy. Benefits of DHEA on pregnancy rates were statistically associated with efficiency of androgen conversion from DHEA to T and amplitude of T gain. Younger women converted significantly more efficiently than older females, and selected FMR1 genotypes/sub-genotypes converted better than others. FSH/androgen and AMH/androgen ratios represent promising new predictors of IVF pregnancy chances in women with DOR. CONCLUSIONS DOR at all ages appears to represent an androgen-deficient state, benefitting from androgen supplementation. Efficacy of androgen supplementation with DHEA, however, varies depending on female age and FMR1 genotype/sub-genotype. Further clarification of FMR1 effects should lead to better individualization of androgen supplementation, whether via DHEA or other androgenic compounds.
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197
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Matsumoto T, Sakari M, Okada M, Yokoyama A, Takahashi S, Kouzmenko A, Kato S. The androgen receptor in health and disease. Annu Rev Physiol 2012; 75:201-24. [PMID: 23157556 DOI: 10.1146/annurev-physiol-030212-183656] [Citation(s) in RCA: 166] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Androgens play pivotal roles in the regulation of male development and physiological processes, particularly in the male reproductive system. Most biological effects of androgens are mediated by the action of nuclear androgen receptor (AR). AR acts as a master regulator of downstream androgen-dependent signaling pathway networks. This ligand-dependent transcriptional factor modulates gene expression through the recruitment of various coregulator complexes, the induction of chromatin reorganization, and epigenetic histone modifications at target genomic loci. Dysregulation of androgen/AR signaling perturbs normal reproductive development and accounts for a wide range of pathological conditions such as androgen-insensitive syndrome, prostate cancer, and spinal bulbar muscular atrophy. In this review we summarize recent advances in understanding of the epigenetic mechanisms of AR action as well as newly recognized aspects of AR-mediated androgen signaling in both men and women. In addition, we offer a perspective on the use of animal genetic model systems aimed at eventually developing novel therapeutic AR ligands.
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Affiliation(s)
- Takahiro Matsumoto
- Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503, Japan.
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198
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Lorenzetti* S, Narciso L. Nuclear Receptors: Connecting Human Health to the Environment. COMPUTATIONAL APPROACHES TO NUCLEAR RECEPTORS 2012. [DOI: 10.1039/9781849735353-00001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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199
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Duda M, Wolna A, Knapczyk-Stwora K, Durlej-Grzesiak M, Knet M, Tabarowski Z, Slomczynska M. The influence of the antiandrogen 2-hydroxyflutamide on the androgen receptor expression in the porcine ovarian follicles - an in vitro study. Reprod Domest Anim 2012; 48:454-62. [PMID: 23113830 DOI: 10.1111/rda.12097] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Accepted: 09/10/2012] [Indexed: 11/28/2022]
Abstract
Androgens are one of the most important agents influencing ovarian follicles growth and development. The biological action of androgens is primarily exerted through transcriptional regulation by the androgen receptor (AR), a member of the steroid hormone receptor superfamily. The purpose of this study was to test the role of androgen receptor agonist testosterone (T) or antagonist 2-hydroxyflutamide (2-Hf) and in combination on AR expression in cultured porcine granulosa cells (GC) or whole follicles. Granulosa cells isolated from mature pig follicles were cultured for 48 h. During the last 12 and 24 h of culture, they were incubated in the presence of T (10(-7) m/ml), 2-Hf (1.7 × 10(-4) m) or both T and 2-Hf (T + 2-Hf, at the same concentrations as when added separately). To better imitate in vivo conditions, whole follicles (6-8 mm in diameter) isolated from porcine ovaries have been incubated (for 12 and 24 h) in an organ culture system with the addition of the same factors. Thereafter, cells or sections obtained from cultured follicles were processed for AR detection by immunocytochemistry or immunohistochemistry. Moreover, expression of AR mRNA and protein was determined by real-time PCR and Western blot analysis. It was shown that the addition of 2-Hf in the presence of T had a positive effect on AR mRNA and protein expression in porcine GC and ovarian follicles. Moreover, the addition of 2-Hf influenced AR distribution in GC cultures which is seen as change of its localization from nuclear to perinuclear. Our results suggest that androgens acting through AR could be involved in the control of AR expression in porcine GC in vitro and in vivo.
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Affiliation(s)
- M Duda
- Department of Endocrinology, Institute of Zoology, Jagiellonian University, Krakow, Poland.
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Hirao Y. Isolation of ovarian components essential for growth and development of mammalian oocytes in vitro. J Reprod Dev 2012; 58:167-74. [PMID: 22738899 DOI: 10.1262/jrd.2011-052] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mammalian ovaries contain a large number of oocytes, most of which degenerate either before or at various stages of growth. Dynamic and precise regulation in the ovary involves many factors, each with a unique role. Identifying the single most important factor is impossible; however, it may be possible to identify factors essential for oocyte growth. It is evident that oocytes can grow into competent ova in vitro; however, how faithfully the follicle should mimic the in vivo conditions remains unclear. In the culture system discussed in this review, bovine and mouse oocyte-granulosa cell complexes, at approximately the late mid-growth stage, spread on a substratum without the involvement of theca cells. The structural simplicity of this system is advantageous because it reduces the basic conditions essential for regulation of oocyte growth. Apart from biological factors, high concentrations of polyvinylpyrrolidone (molecular weight: 360000) improved oocyte growth. Among ovarian factors, androstenedione was used to compensate for the absence of theca cells, and it promoted both follicular growth and acquisition of oocyte meiotic competence. Most oocytes cultured in a group were viable after long-term culture, suggesting that unlike ovarian events, there was no exhaustive follicle selection. Collectively, oocytes and their associated granulosa cells can establish independent units capable of supporting oocyte growth in appropriately modified culture media.
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Affiliation(s)
- Yuji Hirao
- Livestock and Forage Research Division, Tohoku Agricultural Research Center (TARC), National Agriculture and Food Research Organization (NARO), Morioka 020-0198, Japan.
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