scholarly journals Subfertility in androgen-insensitive female mice is rescued by transgenic FSH

2017 ◽  
Vol 29 (7) ◽  
pp. 1426 ◽  
Author(s):  
K. A. Walters ◽  
M. C. Edwards ◽  
M. Jimenez ◽  
D. J. Handelsman ◽  
C. M. Allan
Keyword(s):  
Androgen Receptor ◽  
Litter Size ◽  
Ovarian Function ◽  
Reproductive Function ◽  
Antral Follicle ◽  
Female Fertility ◽  
Wild Type ◽  
Female Reproduction ◽  
Androgen Insensitivity ◽  
Female Mice

Androgens synergise with FSH in female reproduction but the nature of their interaction in ovarian function and fertility is not clear. In the present study, we investigated this interaction, notably whether higher endogenous FSH can overcome defective androgen actions in androgen receptor (AR)-knockout (ARKO) mice. We generated and investigated the reproductive function of mutant mice exhibiting AR resistance with or without expression of human transgenic FSH (Tg-FSH). On the background of inactivated AR signalling, which alone resulted in irregular oestrous cycles and reduced pups per litter, ovulation rates and antral follicle health, Tg-FSH expression restored follicle health, ovulation rates and litter size to wild-type levels. However, Tg-FSH was only able to partially rectify the abnormal oestrous cycles observed in ARKO females. Hence, elevated endogenous FSH rescued the intraovarian defects, and partially rescued the extraovarian defects due to androgen insensitivity. In addition, the observed increase in litter size in Tg-FSH females was not observed in the presence of AR signalling inactivation. In summary, the findings of the present study reveal that FSH can rescue impaired female fertility and ovarian function due to androgen insensitivity in female ARKO mice by maintaining follicle health and ovulation rates, and thereby optimal female fertility.

scholarly journals Female Mice Haploinsufficient for an Inactivated Androgen Receptor (AR) Exhibit Age-Dependent Defects That Resemble the AR Null Phenotype of Dysfunctional Late Follicle Development, Ovulation, and Fertility

Endocrinology ◽  
2007 ◽  
Vol 148 (8) ◽  
pp. 3674-3684 ◽  
Author(s):  
K. A. Walters ◽  
C. M. Allan ◽  
M. Jimenez ◽  
P. R. Lim ◽  
R. A. Davey ◽  
...  
Keyword(s):  
Androgen Receptor ◽  
Ovarian Function ◽  
Gene Dosage ◽  
Early Embryo ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Cell Stage ◽  
Gene Dosage Effect ◽  
Female Mice ◽  
Age Dependent

The role of classical genomic androgen receptor (AR) mediated actions in female reproductive physiology remains unclear. Female mice homozygous for an in-frame deletion of exon 3 of the Ar (AR−/−) were subfertile, exhibiting delayed production of their first litter (AR+/+ = 22 d vs. AR−/− = 61 d, P < 0.05) and producing 60% fewer pups/litter (AR+/+: 8.1 ± 0.4 vs. AR−/−: 3.2 ± 0.9, P < 0.01). Heterozygous females (AR+/−) exhibited an age-dependent 55% reduction (P < 0.01) in pups per litter, evident from 6 months of age (P < 0.05), compared with AR+/+, indicating a significant gene dosage effect on female fertility. Ovulation was defective with a significant reduction in corpora lutea numbers (48–79%, P < 0.01) in 10- to 12- and 26-wk-old AR+/− and AR−/− females and a 57% reduction in oocytes recovered from naturally mated AR−/− females (AR+/+: 9.8 ± 1.0 vs. AR−/−: 4.2 ± 1.2, P < 0.01); however, early embryo development to the two-cell stage was unaltered. The delay in first litter, reduction in natural ovulation rate, and aromatase expression in AR+/− and AR−/− ovaries, coupled with the restored ovulation rate by gonadotropin hyperstimulation in AR−/− females, suggest aberrant gonadotropin regulation. A 2.7-fold increase (AR+/+: 35.4 ± 13.4 vs. AR−/−: 93.9 ± 6.1, P < 0.01) in morphologically unhealthy antral follicles demonstrated deficiencies in late follicular development, although growing follicle populations and growth rates were unaltered. This novel model reveals that classical genomic AR action is critical for normal ovarian function, although not for follicle depletion and that haploinsufficiency for an inactivated AR may contribute to a premature reduction in female fecundity.

scholarly journals Subfertile Female Androgen Receptor Knockout Mice Exhibit Defects in Neuroendocrine Signaling, Intraovarian Function, and Uterine Development But Not Uterine Function

Endocrinology ◽  
2009 ◽  
Vol 150 (7) ◽  
pp. 3274-3282 ◽  
Author(s):  
K. A. Walters ◽  
K. J. McTavish ◽  
M. G. Seneviratne ◽  
M. Jimenez ◽  
A. C. McMahon ◽  
...  
Keyword(s):  
Androgen Receptor ◽  
Knockout Mice ◽  
Growth And Development ◽  
Direct Evidence ◽  
Female Fertility ◽  
Corpora Lutea ◽  
Wild Type ◽  
Uterine Growth ◽  
Uterine Function ◽  
Uterine Development

Female androgen receptor (AR) knockout mice (AR−/−) generated by an in-frame Ar exon 3 deletion are subfertile, but the mechanism is not clearly defined. To distinguish between extra- and intraovarian defects, reciprocal ovarian transplants were undertaken. Ovariectomized AR−/− hosts with wild-type (AR+/+) ovary transplants displayed abnormal estrus cycles, with longer cycles (50%, P < 0.05), and 66% were infertile (P < 0.05), whereas AR+/+ hosts with either AR−/− or surgical control AR+/+ ovary transplants displayed normal estrus cycles and fertility. These data imply a neuroendocrine defect, which is further supported by increased FSH (P <0.05) and estradiol (P <0.05), and greater LH suppressibility by estradiol in AR−/− females at estrus (P <0.05). Additional intraovarian defects were observed by the finding that both experimental transplant groups exhibited significantly reduced pups per litter (P < 0.05) and corpora lutea numbers (P < 0.05) compared with surgical controls. All groups exhibited normal uterine and lactation functions. AR−/− uteri were morphologically different from AR+/+ with an increase in horn length (P < 0.01) but a reduction in uterine diameter (P < 0.05), total uterine area (P < 0.05), endometrial area (P < 0.05), and myometrial area (P < 0.01) at diestrus, indicating a role for AR in uterine growth and development. Both experimental transplant groups displayed a significant reduction in uterine diameter (P < 0.01) compared with transplanted wild-type controls, indicating a role for both AR-mediated intraovarian and intrauterine influences on uterine physiology. In conclusion, these data provide direct evidence that extraovarian neuroendocrine, but not uterine effects, as well as local intraovarian AR-mediated actions are important in maintaining female fertility, and a disruption of AR signaling leads to altered uterine development.

scholarly journals Heterozygous Eif4nif1 Stop Gain Mice Replicate the Primary Ovarian Insufficiency Phenotype

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A774-A775
Author(s):  
Mika Moriwaki ◽  
Corrine Kolka Welt
Keyword(s):  
Mouse Model ◽  
Litter Size ◽  
Average Length ◽  
Reproductive Function ◽  
Protein Translation ◽  
Antral Follicle ◽  
Primary Ovarian Insufficiency ◽  
Primary Follicle ◽  
Ovarian Insufficiency ◽  
Exon 10

Abstract We identified a stop-gain mutation in eIF4ENIF1 in a family in which multiple women developed primary ovarian insufficiency (POI) at approximately age 30 years. We hypothesized that the same mutation in a mouse model would replicate POI. Methods: The Eif4enif1 C57/Bl6 transgenic mouse model contains a floxed exon 10-19 cassette and a conditional knock-in cassette containing exon 10 with the c.1286C>G stop-gain mutation causing familial POI and WT exons 11-19 (Eif4enif1WT/flx). The hybrid offspring of CMV-Cre mice with Eif4enif1WT/flx mice were designated Eif4enif1WT/Δ for simplicity. Follicles were counted in fixed H&E stained ovaries from mice age days 1-5 (primordial and primary follicles), day 10, day 22 (first wave of growing follicles from small preantral to small antral follicles), week 20 (peak fertility), then every 2 months from 10 months to 26 months (follicle exhaustion). Litter frequency, pup number and genotype were recorded. Serum FSH levels were measured by the University of Virginia Ligand Assay and Analysis Core. Results: The heterozygotes have no outward or internal phenotypic differences compared to WT (Eif4enif1WT/flx), with the exception of reproductive organs in females and males. A subset of female heterozygotes (Eif4enif1WT/Δ) had no litters for 20 weeks (2 of 18; 11%). In those with litters, the average length of time between litters was not different but the final litter was earlier (5.6±2.7 vs. 10.5±0.7 months; p=0.02). Heterozygous breeding pair (Eif4enif1WT/Δx Eif4enif1WT/Δ) litter size was 60% of WT litter size (3.9±2.3 vs. 7.2±2.1 pups/litter; 0<0.001). The genotypes were 35% Eif4enif1WT/flx and 65% Eif4enif1WT/Δ, with no homozygotes. The number of follicles in ovaries from Eif4enif1WT/Δ mice was lower starting at the primordial (499±290 vs. 1445±381) and primary follicle stage (1069±346 vs. 1450±193) on day 10 (p<0.05). The preantral follicle number was lower starting on day 21 (213±86 vs. 522±227; p<0.01) and the antral follicle count was lower starting on week 20 (78±38 vs. 119±18; p<0.01). The FSH level in 12-month old mice during estrus was higher in a heterozygote compared to WT (25.0 vs. 12.1 ng/mL). Conclusions: Heterozygous Eif4enif1 stop-gain mutants have follicle loss documented by day 10, decreased pup number with no homozygotes, earlier end of reproductive function and elevated FSH levels. These mice replicate the POI phenotype in women. eIF4ENIF1 regulates protein translation by binding and storing eIF4E bound mRNA. Therefore, the unique mouse model provides a platform to study temporal and spatial regulation of protein translation across oocyte and embryo development in mammals. Further studies will determine whether follicle loss results from premature protein translation in oocytes.

scholarly journals Effect of androgen treatment during foetal and/or neonatal life on ovarian function in prepubertal and adult rats

Reproduction ◽  
2012 ◽  
Vol 143 (1) ◽  
pp. 21-33 ◽  
Author(s):  
Victoria Tyndall ◽  
Marie Broyde ◽  
Richard Sharpe ◽  
Michelle Welsh ◽  
Amanda J Drake ◽  
...  
Keyword(s):  
Ovarian Function ◽  
Polycystic Ovary ◽  
Time Windows ◽  
Reproductive Function ◽  
Antral Follicle ◽  
Female Rats ◽  
Postnatal Life ◽  
Adult Rats ◽  
Stromal Compartment ◽  
Neonatal Life

We investigated the effects of different windows of testosterone propionate (TP) treatment during foetal and neonatal life in female rats to determine whether and when excess androgen exposure would cause disruption of adult reproductive function. Animals were killed prepubertally at d25 and as adults at d90. Plasma samples were taken for hormone analysis and ovaries serial sectioned for morphometric analyses. In prepubertal animals, only foetal+postnatal and late postnatal TP resulted in increased body weights, and an increase in transitory, but reduced antral follicle numbers without affecting total follicle populations. Treatment with TP during both foetal+postnatal life resulted in the development of streak ovaries with activated follicles containing oocytes that only progressed to a small antral (smA) stage and inactive uteri. TP exposure during foetal or late postnatal life had no effect upon adult reproductive function or the total follicle population, although there was a reduction in the primordial follicle pool. In contrast, TP treatment during full postnatal life (d1–25) resulted in anovulation in adults (d90). These animals were heavier, had a greater ovarian stromal compartment, no differences in follicle thecal cell area, but reduced numbers of anti-Mullerian hormone-positive smA follicles when compared with controls. Significantly reduced uterine weights lead reduced follicle oestradiol production. These results support the concept that androgen programming of adult female reproductive function occurs only during specific time windows in foetal and neonatal life with implications for the development of polycystic ovary syndrome in women.

scholarly journals Androgen Receptor Mutations Identified in Prostate Cancer and Androgen Insensitivity Syndrome Display Aberrant ART-27 Coactivator Function

2005 ◽  
Vol 19 (9) ◽  
pp. 2273-2282 ◽  
Author(s):  
Wenhui Li ◽  
Claudio N. Cavasotto ◽  
Timothy Cardozo ◽  
Susan Ha ◽  
Thoa Dang ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Transcriptional Activation ◽  
Transcriptional Response ◽  
Androgen Insensitivity Syndrome ◽  
Wild Type ◽  
Transcriptional Responses ◽  
Androgen Insensitivity ◽  
Naturally Occurring ◽  
Type Receptor

Abstract The transcriptional activity of the androgen receptor (AR) is modulated by interactions with coregulatory molecules. It has been proposed that aberrant interactions between AR and its coregulators may contribute to diseases related to AR activity, such as prostate cancer and androgen insensitivity syndrome (AIS); however, evidence linking abnormal receptor-cofactor interactions to disease is scant. ART-27 is a recently identified AR N-terminal coactivator that is associated with AR-mediated growth inhibition. Here we analyze a number of naturally occurring AR mutations identified in prostate cancer and AIS for their ability to affect AR response to ART-27. Although the vast majority of AR mutations appeared capable of increased activation in response to ART-27, an AR mutation identified in prostate cancer (AR P340L) and AIS (AR E2K) show reduced transcriptional responses to ART-27, whereas their response to the p160 class of coactivators was not diminished. Relative to the wild-type receptor, less ART-27 protein associated with the AR E2K substitution, consistent with reduced transcriptional response. Surprisingly, more ART-27 associated with AR P340L, despite the fact that the mutation decreased transcriptional activation in response to ART-27. Our findings suggest that aberrant AR-coactivator association interferes with normal ART-27 coactivator function, resulting in suppression of AR activity, and may contribute to the pathogenesis of diseases related to alterations in AR activity, such as prostate cancer and AIS.

scholarly journals Role of androgens in normal and pathological ovarian function

Reproduction ◽  
2015 ◽  
Vol 149 (4) ◽  
pp. R193-R218 ◽  
Author(s):  
K A Walters
Keyword(s):  
Animal Models ◽  
Ovarian Function ◽  
Female Fertility ◽  
Female Reproduction ◽  
Mediated Effects ◽  
Reproductive Disorder ◽  
Pharmacological Studies ◽  
And Function ◽  
Ovarian Syndrome

Androgens mediate their actions via the androgen receptor (AR), a member of the nuclear receptor superfamily. AR-mediated androgen action is essential in male reproductive development and function; however, only in the last decade has the suspected but unproven role for AR-mediated actions in female reproduction been firmly established. Deciphering the specific roles and precise pathways by which AR-mediated actions regulate ovarian function has been hindered by confusion on how to interpret results from pharmacological studies using androgens that can be converted into oestrogens, which exert actions via the oestrogen receptors. The generation and analysis of global and cell-specific femaleArknockout mouse models have deduced a role for AR-mediated actions in regulating ovarian function, maintaining female fertility, and have begun to unravel the mechanisms by which AR-mediated androgen actions regulate follicle health, development and ovulation. Furthermore, observational findings from human studies and animal models provide substantial evidence to support a role for AR-mediated effects not only in normal ovarian function but also in the development of the frequent ovarian pathological disorder, polycystic ovarian syndrome (PCOS). This review focuses on combining the findings from observational studies in humans, pharmacological studies and animal models to reveal the roles of AR-mediated actions in normal and pathological ovarian function. Together these findings will enable us to begin understanding the important roles of AR actions in the regulation of female fertility and ovarian ageing, as well as providing insights into the role of AR actions in the androgen-associated reproductive disorder PCOS.

scholarly journals Physiologic Course of Female Reproductive Function: A Molecular Look into the Prologue of Life

2015 ◽  
Vol 2015 ◽  
pp. 1-21 ◽  
Author(s):  
Joselyn Rojas ◽  
Mervin Chávez-Castillo ◽  
Luis Carlos Olivar ◽  
María Calvo ◽  
José Mejías ◽  
...  
Keyword(s):  
Reproductive Function ◽  
Prenatal Development ◽  
Female Fertility ◽  
Ovarian Hormone ◽  
Follicular Growth ◽  
Female Reproduction ◽  
Metabolic Disturbances ◽  
Pregnancy And Postpartum ◽  
Strict Regulation ◽  
Hormone Sensitive

The genetic, endocrine, and metabolic mechanisms underlying female reproduction are numerous and sophisticated, displaying complex functional evolution throughout a woman’s lifetime. This vital course may be systematized in three subsequent stages: prenatal development of ovaries and germ cells up untilin uteroarrest of follicular growth and the ensuing interim suspension of gonadal function; onset of reproductive maturity through puberty, with reinitiation of both gonadal and adrenal activity; and adult functionality of the ovarian cycle which permits ovulation, a key event in female fertility, and dictates concurrent modifications in the endometrium and other ovarian hormone-sensitive tissues. Indeed, the ultimate goal of this physiologic progression is to achieve ovulation and offer an adequate environment for the installation of gestation, the consummation of female fertility. Strict regulation of these processes is important, as disruptions at any point in this evolution may equate a myriad of endocrine-metabolic disturbances for women and adverse consequences on offspring both during pregnancy and postpartum. This review offers a summary of pivotal aspects concerning the physiologic course of female reproductive function.

scholarly journals Androgen-induced epigenetic modulations in the ovary

2021 ◽  
Vol 249 (3) ◽  
pp. R53-R64
Author(s):  
Irving Salinas ◽  
Niharika Sinha ◽  
Aritro Sen
Keyword(s):  
Androgen Receptor ◽  
Ovarian Function ◽  
Polycystic Ovary ◽  
Underlying Mechanism ◽  
Female Reproduction ◽  
Nuclear Signaling ◽  
Downstream Effects ◽  
Androgen Exposure ◽  
Epigenetic Modulation ◽  
Developmental Reprogramming

In recent years, androgens have emerged as critical regulators of female reproduction and women’s health in general. While high levels of androgens in women are associated with polycystic ovary syndrome (PCOS), recent evidence suggests that a certain amount of direct androgen action through androgen receptor is also essential for normal ovarian function. Moreover, prenatal androgen exposure has been reported to cause developmental reprogramming of the fetus that manifests into adult pathologies, supporting the Developmental Origins of Health and Disease (DOHaD) hypothesis. Therefore, it has become imperative to understand the underlying mechanism of androgen actions and its downstream effects under normal and pathophysiological conditions. Over the years, there has been a lot of studies on androgen receptor function as a transcriptional regulator in the nucleus as well as androgen-induced rapid extra-nuclear signaling. Conversely, new evidence suggests that androgen actions may also be mediated through epigenetic modulation involving both the nuclear and extra-nuclear androgen signaling. This review focuses on androgen-induced epigenetic modifications in female reproduction, specifically in the ovary, and discusses emerging concepts, latest perceptions, and highlight the areas that need further investigation.

scholarly journals A Phosphotyrosine Switch in Estrogen Receptor β Is Required for Mouse Ovarian Function

2021 ◽  
Vol 9 ◽  
Author(s):  
Bin Yuan ◽  
Jing Yang ◽  
Louis Dubeau ◽  
Yanfen Hu ◽  
Rong Li
Keyword(s):  
Breast Cancer Cells ◽  
Target Genes ◽  
Ovarian Function ◽  
Physiological Role ◽  
Molecular Evidence ◽  
Wild Type ◽  
Female Mice ◽  
Mutant Female ◽  
And Function

The two homologous estrogen receptors ERα and ERβ exert distinct effects on their cognate tissues. Previous work from our laboratory identified an ERβ-specific phosphotyrosine residue that regulates ERβ transcriptional activity and antitumor function in breast cancer cells. To determine the physiological role of the ERβ phosphotyrosine residue in normal tissue development and function, we investigated a mutant mouse model (Y55F) whereby this particular tyrosine residue in endogenous mouse ERβ is mutated to phenylalanine. While grossly indistinguishable from their wild-type littermates, mutant female mice displayed reduced fertility, decreased ovarian follicular cell proliferation, and lower progesterone levels. Moreover, mutant ERβ from female mice during superovulation is defective in activating promoters of its target genes in ovarian tissues. Thus, our findings provide compelling genetic and molecular evidence for a role of isotype-specific ERβ phosphorylation in mouse ovarian development and function.

scholarly journals Effect of neuronal nitric oxide synthase serine-1412 phosphorylation on hypothalamic–pituitary–ovarian function and leptin response

2020 ◽  
Vol 102 (6) ◽  
pp. 1281-1289 ◽  
Author(s):  
Damian D Guerra ◽  
Rachael Bok ◽  
Evelyn Llerena Cari ◽  
Cari Nicholas ◽  
David J Orlicky ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Estrous Cycle ◽  
Ovarian Function ◽  
Neuronal Nitric Oxide Synthase ◽  
Cycle Duration ◽  
Wild Type ◽  
Female Reproduction ◽  
Organ Systems ◽  
Oxide Synthase

Abstract Hypothalamic neuronal nitric oxide synthase (nNOS) potentiates adult female fertility in rodents by stimulating gonadotropin releasing hormone (GnRH) secretion, which in turn promotes luteinizing hormone (LH) release and ovulation. The mechanism of hypothalamic nNOS activation is not clear but could be via nNOS serine1412 (S1412) phosphorylation, which increases nNOS activity and physiologic NO effects in other organ systems. In female rodents, hypothalamic nNOS S1412 phosphorylation reportedly increases during proestrus or upon acute leptin exposure during diestrus. To determine if nNOS S1412 regulates female reproduction in mice, we compared the reproductive anatomy, estrous cycle duration and phase proportion, and fecundity of wild-type and nNOS serine1412➔alanine (nNOSS1412A) knock-in female mice. We also measured hypothalamic GnRH and serum LH, follicle stimulating hormone (FSH), estradiol, and progesterone in diestrus mice after intraperitoneal leptin injection. Organ weights and histology were not different by genotype. Ovarian primordial follicles, antral follicles, and corpora lutea were similar for wild-type and nNOSS1412A mice. Likewise, estrous cycle duration and phase length were not different, and fecundity was unremarkable. There were no differences among genotypes for LH, FSH, estradiol, or progesterone. In contrast to prior studies, our work suggests that nNOS S1412 phosphorylation is dispensable for normal hypothalamic–pituitary–ovarian function and regular estrous cycling. These findings have important implications for current models of fertility regulation by nNOS phosphorylation.

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