An agonist for membrane progestin receptor (mPR) induces oocyte maturation and ovulation in zebrafish in vivo

Progestin stimulation of sperm hypermotility remains poorly understood despite having been described in numerous vertebrate species. We show here that progestin stimulation of sperm hypermotility in a teleost, the Atlantic croaker (Micropogonias undulatus) is associated with activation of an olfactory G protein (Golf). Furthermore, we provide evidence that this progestin action is mediated by membrane progestin receptor-α (mPRα). Golf was identified in croaker sperm membranes and was specifically activated after treatment with the progestin 17,20β,21-trihydroxy-4-pregnen-3-one (20β-S). Treatment of sperm membranes with 20β-S caused an increase in cAMP production, which was blocked by pretreatment with cholera toxin and two membrane adenylyl cyclase inhibitors: 2′,5′-dideoxyadenosine and SQ22536. Moreover, preincubation of croaker sperm with 2′,5′-dideoxyadenosine and SQ22536 resulted in a significant inhibition of 20β-S-stimulated hypermotility. Binding of [3H]20β-S to sperm membranes was decreased after pretreatment with GTPγS but not pertussis toxin, suggesting the receptor is coupled to a pertussis toxin-insensitive G protein. Golf and mPRα were coexpressed on the sperm midpiece and flagella and were coimmunoprecipitated from sperm membranes. Finally, expression of mPRα protein on sperm increased after in vivo treatment with LHRH and was associated with increased induction of sperm motility by 20β-S. These results suggest that 20β-S activates mPRα in croaker sperm, which in turn activates Golf and membrane adenylyl cyclase to stimulate sperm hypermotility. Taken together these findings provide a plausible mechanism by which progestins stimulate sperm hypermotility in croaker and provide the first evidence of hormonal activation of Golf in any species. Progestin activation of an olfactory G protein pathway, likely through membrane progestin receptor alpha, is associated with induction of hypermotility in Atlantic croaker sperm.

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Fine selection of up-regulated genes during ovulation by in vivo induction of oocyte maturation and ovulation in zebrafish

Zoological Letters ◽

10.1186/s40851-017-0065-8 ◽

2017 ◽

Vol 3 (1) ◽

Cited By ~ 1

Author(s):

Wanlada Klangnurak ◽

Toshinobu Tokumoto

Keyword(s):

Oocyte Maturation ◽

In Vivo Induction ◽

Selection Of

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Rac1 is dispensable for oocyte maturation and female fertility in vivo

PLoS ONE ◽

10.1371/journal.pone.0177202 ◽

2017 ◽

Vol 12 (5) ◽

pp. e0177202 ◽

Cited By ~ 1

Author(s):

Jian-Xiu Hao ◽

Tie-Gang Meng ◽

Li-Hua Fan ◽

Yuan-Qing Yao

Keyword(s):

Oocyte Maturation ◽

Female Fertility

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Induction of sperm hypermotility through membrane progestin receptor alpha (mPRα): A teleost model of rapid, multifaceted, nongenomic progestin signaling

General and Comparative Endocrinology ◽

10.1016/j.ygcen.2018.12.002 ◽

2019 ◽

Vol 279 ◽

pp. 60-66 ◽

Cited By ~ 2

Author(s):

Wenxian Tan ◽

Yefei Pang ◽

Christopher Tubbs ◽

Peter Thomas

Keyword(s):

Receptor Alpha ◽

Progestin Receptor ◽

Membrane Progestin Receptor

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Investigating the Intrafollicular Factors Affecting Oocyte Developmental Competency

10.26686/wgtn.17068070.v1 ◽

2021 ◽

Author(s):

◽

Zaramasina Clark

Keyword(s):

Gene Expression ◽

Oocyte Maturation ◽

Granulosa Cells ◽

Embryo Quality ◽

Cumulus Cells ◽

Significant Finding ◽

High Quality ◽

Final Maturation

<p>The number of cycles of assisted reproductive technologies (ART) performed increased by ~9.5 % globally between 2008 and 2010. In spite of this, the success rate in terms of delivery was only ~19.0 % (Dyer et al., 2016). This discrepancy between the demand for, and success of, these technologies necessitates the development of tools to improve ART efficiency. To facilitate this, a better understanding of how the microenvironment changes within the developing follicle to culminate in a mature, developmentally-competent oocyte is required. This study employed an in vivo and in vitro ovine model to investigate the relationship between the surrounding microenvironment and oocyte maturation, and in particular, the attainment of oocyte developmental competency and high-quality embryos. The first objective of this PhD study was to comprehensively investigate the changing microenvironment of in vivo matured, presumptive preovulatory (PPOV) follicles from wild-type (++) and high ovulation rate (OR; I+B+) ewes. The high OR ewes were heterozygous carriers of mutations in BMP15 (I+) and BMPRIB (B+). Functional differences in follicular somatic (granulosa and cumulus) cells between these genotypes, including differential gonadotropin responsiveness of granulosa cells, composition of follicular fluid and gene expression profiles in cumulus cells were evident. These differences emerged as part of a compensatory mechanism by which oocytes from smaller follicles, containing fewer granulosa cells, achieved developmental competency in I+B+ ewes. The second objective of this PhD study was to develop new approaches for improving current in vitro maturation (IVM) strategies. The first approach utilised in this study focused on developing biomarkers that could be used to improve prediction of developmental competency in oocytes and in vitro produced embryos. This involved interrogating the hypothesis that a combination of molecular and morphokinetic biomarkers would better predict the developmental competency of oocytes and embryos compared to using these biomarkers alone. The second approach utilised in this PhD study tested the effects of modulating IVM conditions to better mimic the follicular microenvironment of a high, compared to a low, OR species on oocyte developmental competency and embryo quality. This involved supplementing IVM media with different ratios of two oocyte-secreted growth factors, i.e. GDF9:BMP15, that were representative of low or high OR species. These approaches demonstrated significant potential and warrant further investigation. The most significant finding of this study was that despite variances in the surrounding microenvironment during in vivo and in vitro oocyte maturation that culminated in differential gene expression patterns in cumulus cells, and divergent gonadotropin-responsiveness of granulosa cells, the gene expression signatures of developmentally-competent oocytes and the morphokinetics of high-quality embryos were unaltered. This confirms the value of developing such biomarkers for oocyte development competency and embryo quality that remain unaltered despite a changing surrounding environment. Interestingly, simulating the ratio of GDF9:BMP15 that oocytes from high OR species are exposed to during maturation improved developmental competency in oocytes as demonstrated by increased blastocyst rates. Furthermore, this study has demonstrated that combinations of molecular (cumulus cell gene expression) and morphokinetic biomarkers improved the ability to predict developmental competency in oocytes and embryos. Overall, this study revealed novel information regarding the follicular microenvironment during final maturation and identified several novel approaches to improving the efficiency of ART.</p>

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P–199 A case report to suggest that there must be other mutations than PATL2 or TUBB8 to cause oocyte maturation arrest

Human Reproduction ◽

10.1093/humrep/deab130.198 ◽

2021 ◽

Vol 36 (Supplement_1) ◽

Author(s):

E Molinari ◽

M Yang ◽

J Hu ◽

L Zhang ◽

D F Albertini ◽

...

Keyword(s):

Case Report ◽

Oocyte Maturation ◽

Fertilization Rate ◽

Functional Study ◽

Embryo Morphology ◽

Loss Of Function ◽

Maturation Arrest ◽

Polar Bodies

Abstract Study question What causes our patient’s repeated almost complete oocyte maturation arrest (OMA)? Summary answer Since we did not detect PATL2 and TUBB8 mutations, both known to cause OMA, this case was likely caused by mutations in HUS1 and ITGB3 What is known already OMA has been associated with loss-of-function in key genes, such as PATL2 and TUBB8. Such patients have, however, uniformly have been unable to conceive with IVF Study design, size, duration We here report the case of repeatedly presenting patient between 2009 until 2020 (age 30 at 1st and 41 at last visit). Participants/materials, setting, methods The couple underwent 7 IVF treatments under several ovarian stimulation protocols at different gonadotropin dosages and in different preparations to try to recruit mature eggs. She conceived in her 2nd IVF cycle in 2009 and delivered uneventfully in 2010. She then conceived spontaneously and delivered a healthy boy in 2014. The couple since then has been attempting another pregnancy. Remarkably, in all IVF cycles all eggs but one arrested at prophase. Main results and the role of chance The female demonstrates abnormally high ovarian reserve for age (AMH=5.9 ng/mL in 2019) (mean, 10.6 oocytes). In all cycles, all but one retrieved were immature. In vitro maturation rate for the GV oocytes was 28%. Resultant M2s, however, demonstrated morphological abnormalities, such as giant polar bodies. In vivo M2s, in contrast, were always morphologically unremarkable, and their fertilization rate was 85%. Embryo morphology deteriorated appreciatively with advancing age. Sanger sequencing for TUBB8 and PATL2 genes were unremarkable. Whole genome sequencing of her and her sister (who had no fertility problems) revealed mutations of genes belonging to the integrin family (ITGB3) and DNA repair checkpoint (HUS1), both of which could be determinants in the observed maturation arrest. Limitations, reasons for caution A functional study, coupled with imaging of the discarded material, will likely offer further information regarding the mechanisms leading to OMA in this female. Wider implications of the findings: This case report represents a new phenotype of female infertility, characterized by almost complete maturation arrest which, however, still offers opportunity for pregnancy. Further isolation of underlying mutation(s) may offer additional insights about checkpoints required for the transition of prophase to metaphase in human oocytes. Trial registration number NA

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P–442 Cancer does not adversely affect oocyte maturation in vitro with the exception of breast cancer

Human Reproduction ◽

10.1093/humrep/deab130.441 ◽

2021 ◽

Vol 36 (Supplement_1) ◽

Author(s):

I Viran. . Klun ◽

J Bedenk ◽

N Jancar

Keyword(s):

Breast Cancer ◽

Cancer Patients ◽

Oocyte Maturation ◽

In Vitro Maturation ◽

Hormonal Stimulation ◽

Infertile Women ◽

Maturation In Vitro ◽

Infertile Patients

Abstract Study question Do different types of cancer affect the success of oocyte maturation in vitro compared to infertile women included in the in vitro fertilization (IVF) program? Summary answer Cancer does not adversely affect oocyte maturation in vitro, with the exception of breast cancer, compared to infertile women in the in vitro fertilization program. What is known already Vitrification and storage of oocytes in liquid nitrogen is one of the real options for maintaining reproductive function in cancer patients. Despite careful hormonal stimulation of the ovaries, however, the proportion of oocytes is immature and lost to the patient. In vitro maturation of oocytes can play an important role in resolving immature oocytes and increasing the chances of conception in cancer patients. Moreover, it can mean a safe way to store oocytes when ovarian hormonal stimulation could worsen the disease. Therefore, the aim of this study was to determine whether different types of cancer affect oocyte in vitro maturation. Study design, size, duration After ovarian stimulation in 18 cancer patients, the number and maturity of oocytes were compared to 21 infertile patients in the IVF program over a three-year period. In both groups, 119 germinal vesicle-GV oocytes were matured in vitro to compare the maturation rate. After IVF in a subset of 17 infertile patients, the fertilization of in vitro and in vivo matured oocytes was compared in the same cycles. The procedure was considered in cancer patients. Participants/materials, setting, methods In this prospective study, forty-five GV oocytes in cancer patients and 74 GV oocytes in infertile patients underwent in vitro maturation procedure. Each oocyte was matured in vitro in the MediCult IVM System by conditioning in LAG medium and maturation for up to 28 hours in IVM medium with added hormones FSH and hCG, in coculture with cumulus cells from mature oocytes in the same patients. Oocytes were fertilized by intracytoplasmic sperm injection (ICSI). Main results and the role of chance After controlled ovarian hormonal stimulation, 198 oocytes were retrieved in cancer patients and 259 oocytes in infertile women and there were no significant differences in the number of retrieved oocytes, proportion of degenerated oocytes and proportion of GV oocytes. In cancer patients, the proportion of oocytes that matured in vitro was lower than in infertile patients (66.0 vs. 80.0%), but the difference was not significant. Among cancer patients, the oocyte maturation rate tended to be lower in patients with breast cancer than in patients with other cancers (54.5% vs. 81.2%; difference not significant). However, in patients with breast cancer, significantly fewer oocytes matured in vitro than in infertile patients (54.5% vs. 80.0%; P < 0.05, Chi-Square test) even though they tended to be younger (29.3 ± 7.4 vs. 33.4 ± 5.0 years; non-significant difference). After in vitro maturation, there was a 13% increase in mature oocyte yield in cancer patients and a 20.1% increase in infertile women with no significant difference observed. After ICSI in a subset of infertile women, there was approximately the same fertilization rate between oocytes matured in vitro and in vivo (55.1% vs. 57.0%) in the same cycles. Limitations, reasons for caution For ICSI in oocytes matured in vitro, we had to use semen collected the day before, while oocytes matured in vivo were fertilized with fresh semen in the same cycle. Therefore, we could not compare the development of embryos in both groups. Wider implications of the findings: In vitro maturation of oocytes in connection with their vitrification or vitrification of embryos after their fertilization appears to be a valuable way to maintain the fertility of young cancer patients, but a worse outcome is expected in breast cancer patients. Trial registration number National Medical Ethical Committee Approval, No. 0120–222/2016–2; KME 115/04/16.

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