Müllerian-inhibiting substance inhibits cytochrome P450 aromatase activity in human granulosa lutein cell culture

The Role of Anti-Müllerian Hormone in Ovarian Function

Anti-Müllerian hormone (AMH) is a member of the transforming growth factor β (TGFβ) superfamily, whose actions are restricted to the endocrine-reproductive system. Initially known for its role in male sex differentiation, AMH plays a role in the ovary, acting as a gatekeeper in folliculogenesis by regulating the rate of recruitment and growth of follicles. In the ovary, AMH is predominantly expressed by granulosa cells of preantral and antral follicles (i.e., post primordial follicle recruitment and prior to follicle-stimulating hormone (FSH) selection). AMH signals through a BMP-like signaling pathway in a manner distinct from other TGFβ family members. In this review, the latest insights in AMH processing, signaling, its regulation of spatial and temporal expression pattern, and functioning in folliculogenesis are summarized. In addition, effects of AMH variants on ovarian function are reviewed.

Anti-Mullerian Hormone and Fertility Treatment Decisions in Polycystic Ovary Syndrome: A Literature Review

Anti-Mullerian hormone is a robust marker of ovarian reserve and ovarian response in in vitro fertilisation (IVF). However, its role extends beyond improving the safety of IVF by aiding in choosing appropriate protocols and dosing. This review looks at the value of pre-treatment anti-Mullerian hormone (AMH) value in choosing the appropriate modality of treatment and its predictive ability for the outcomes of such treatment. It briefly addresses the factors that may modulate AMH levels and make clinical decision-making challenging.

Transcriptome Analysis of Granulosa Cells Reveals Regulatory Mechanisms Related to Chicken Follicle Development

In this study, we aimed to better understand the difference between the functions of the two types of granulosa cells and sought to discover more key genes involved in follicle development and follicle selection. Herein, we separately collected pre-hierarchical follicle granulosa cells (PHGCs) and preovulatory follicle granulosa cells (POGCs) for RNA extraction; the transcriptomes of the two groups were compared via RNA-seq. A total of 5273 differentially expressed genes (DEGs) were identified between the PHGCs and POGCs; 2797 genes were up-regulated and 2476 were down-regulated in the PHGCs compared with the POGCs. A qPCR analysis confirmed that the expression patterns of 16 randomly selected DEGs were highly consistent with the RNA-seq results. In the POGCs, many of the genes with the most significant increase in expression were related to steroid hormone synthesis. In addition, the genes with the most significant decline in expression, including AMH and WT1, were related to the inhibition of steroid hormone synthesis. These results suggest that steroid hormones play a key role in follicle development. Furthermore, a Gene Ontology (GO) analysis revealed that these DEGs were mainly involved in the primary metabolic process, the carbohydrate metabolic process, the cellular process, ribosomes, the cytoplasm, and intracellular processes. A Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the DEGs were mainly enriched in steroid biosynthesis, the cell cycle, ribosomes, the TGF-beta signaling pathway, focal adhesion, and so on. We also observed the morphology of the follicles at different developmental stages, and the results showed that the thickness of the granular layer of the small yellow follicles (SYFs) decreased significantly with further development. In addition, we also found that the thickness of the granulosa layer of hens over 300 days old was significantly lower than that of 200-day-old hens. In short, these data indicate that the tissue morphology and function of granulosa cells change throughout follicle development.

New insights into the role of LH in early ovarian follicular growth: a possible tool to optimize follicular recruitment

Evidence shows that LH participates in enhancing transition from the early stage to the antral stage of folliculogenesis. It has been demonstrated that functional LH receptors are expressed, albeit at a very low level and even in smaller follicles, during the phase that was traditionally considered to be gonadotrophin independent, suggesting a role for LH in accelerating the rate of progression of non-growing and primary follicles to the preantral/antral stage. Hypogonadotropic hypogonadism, together with other clinical conditions of pituitary suppression, has been associated with reduced functional ovarian reserve. The reduction in LH serum concentration is associated with a low concentration of anti-Müllerian hormone. This is the case in hypothalamic amenorrhoea, pregnancy, long-term GnRH-analogue therapy and hormonal contraception. The effect seems to be reversible, such that after pregnancy and after discontinuation of drugs, the functional ovarian reserve returns to the baseline level. Evidence suggests that women with similar primordial follicle reserves could present with different numbers of antral follicles, and that gonadotrophins may play a fundamental role in permitting a normal rate of progression of follicles through non-cyclic folliculogenesis. The precise role of gonadotrophins in early folliculogenesis, as well as their use to modify the functional ovarian reserve, must be investigated.

Durable contraception in the female domestic cat using viral-vectored delivery of a feline anti-Müllerian hormone transgene

Eighty percent of the estimated 600 million domestic cats in the world are free-roaming. These cats typically experience suboptimal welfare and inflict high levels of predation on wildlife. Additionally, euthanasia of healthy animals in overpopulated shelters raises ethical considerations. While surgical sterilization is the mainstay of pet population control, there is a need for efficient, safe, and cost-effective permanent contraception alternatives. Herein, we report evidence that a single intramuscular treatment with an adeno-associated viral vector delivering an anti-Müllerian hormone transgene produces long-term contraception in the domestic cat. Treated females are followed for over two years, during which transgene expression, anti-transgene antibodies, and reproductive hormones are monitored. Mating behavior and reproductive success are measured during two mating studies. Here we show that ectopic expression of anti-Müllerian hormone does not impair sex steroids nor estrous cycling, but prevents breeding-induced ovulation, resulting in safe and durable contraception in the female domestic cat.

Molecular characterization of extracellular vesicles derived from follicular fluid of women with and without PCOS: integrating analysis of differential miRNAs and proteins reveals vital molecules involving in PCOS

PURPOSE

To elucidate the characterization of extracellular vesicles (EVs) in the follicular fluid-derived extracellular vesicles (FF-EVs) and discover critical molecules and signaling pathways associating with the etiology and pathobiology of PCOS, the differentially expressed miRNAs (DEmiRNAs) and differentially expressed proteins profiles (DEPs) were initially explored and combinedly analyzed.

METHODS

First, the miRNA and protein expression profiles of FF-EVs in PCOS patients and control patients were compared by RNA-sequencing and tandem mass tagging (TMT) proteomic methods. Subsequently, Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes were used to analyze the biological function of target genes of DEmiRNAs and DEPs. Finally, to discover the functional miRNA-target gene-protein interaction pairs involved in PCOS, DEmiRs target gene datasets and DEPs datasets were used integratedly.

RESULTS

A total of 6 DEmiRNAs and 32 DEPs were identified in FF-EVs in patients with PCOS. Bioinformatics analysis revealed that DEmiRNAs target genes are mainly involved in thiamine metabolism, insulin secretion, GnRH, and Apelin signaling pathway, which are closely related to the occurrence of PCOS. DEPs also closely related to hormone metabolism processes such as steroid hormone biosynthesis. In the analysis integrating DEmiRNAs target genes and DEPs, two molecules, GRAMD1B and STPLC2, attracted our attention that are closely associated with cholesterol transport and ceramide biosynthesis, respectively.

CONCLUSION

Dysregulated miRNAs and proteins in FF-EVs, mainly involving in hormone metabolism, insulin secretion, neurotransmitters regulation, adipokine expression, and secretion, may be closely related to PCOS. The effects of GRAMD1B and STPLC2 on PCOS deserve further study.

Serum anti-Müllerian hormone levels are associated with perinatal outcomes in women undergoing IVF/ICSI: A multicenter retrospective cohort study

INTRODUCTION

Anti-Müllerian hormone (AMH) level has long been considered as a serum biomarker of ovarian reserve clinically, while emerging data suggest that serum AMH level may also predict pregnancy outcomes. However, whether pregestational serum AMH levels are related to perinatal outcomes among women undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles is unknown.

OBJECTIVE

To explore the association between different AMH levels and perinatal outcomes in women with live births in IVF/ICSI.

METHODS

This multicenter retrospective cohort study was conducted among three different provinces in China, from January 2014 to October 2019. A total of 13,763 IVF/ICSI cycles with 5657 live-delivery pregnant women and 6797 newborns were recruited. Participants were categorized into three groups according to the <25th (low), 25 to 75th (average), and >75th (high) percentile of serum AMH concentration. Perinatal outcomes were compared among groups. Subgroup analyses were conducted based on the number of live births.

RESULTS

Among women with singleton deliveries, low and high AMH levels increased the risk of intrahepatic cholestasis of pregnancy (ICP) (aOR1 = 6.02, 95%CI: 2.10-17.22; aOR2 = 3.65, 95%CI:1.32-10.08) and decreased the risk of macrosomia (aOR1 = 0.65, 95%CI:0.48-0.89; aOR2 = 0.72, 95%CI:0.57-0.96), while low AMH reduced the risk of large for gestational age (LGA, aOR=0.74, 95%CI:0.59-0.93) and premature rupture of membrane (PROM, aOR=0.50, 95%CI:0.31-0.79)compared with the average AMH group. In women with multiple deliveries, high AMH levels increased the risks of gestational diabetes mellitus (GDM, aOR=2.40, 95%CI:1.48-3.91) and pregnancy-induced hypertension (PIH, aOR=2.26, 95%CI:1.20-4.22) compared with the average AMH group, while low AMH levels increased the risk of ICP (aOR=14.83, 95%CI:1.92-54.30). However, there was no evidence of differences in preterm birth, congenital anomaly, and other perinatal outcomes among the three groups in both singleton and multiple deliveries.

CONCLUSIONS

Abnormal AMH levels increased the risk of ICP regardless of the number of live births for women undergoing IVF/ICSI, while high AMH levels increased the risks of GDM and PIH in multiple deliveries. However, serum AMH levels were not associated with adverse neonatal outcomes in IVF/ICSI. The underlying mechanism warrants further investigation.

Age-related changes in Folliculogenesis and potential modifiers to improve fertility outcomes - A narrative review

Reproductive aging is characterized by a decline in oocyte quantity and quality, which is directly associated with a decline in reproductive potential, as well as poorer reproductive success and obstetrical outcomes. As women delay childbearing, understanding the mechanisms of ovarian aging and follicular depletion have become increasingly more relevant. Age-related meiotic errors in oocytes are well established. In addition, it is also important to understand how intraovarian regulators change with aging and how certain treatments can mitigate the impact of aging. Individual studies have demonstrated that reproductive pathways involving antimullerian hormone (AMH), vascular endothelial growth factor (VEGF), neurotropins, insulin-like growth factor 1 (IGF1), and mitochondrial function are pivotal for healthy oocyte and cumulus cell development and are altered with increasing age. We provide a comprehensive review of these individual studies and explain how these factors change in oocytes, cumulus cells, and follicular fluid. We also summarize how modifiers of folliculogenesis, such as vitamin D, coenzyme Q, and dehydroepiandrosterone (DHEA) may be used to potentially overcome age-related changes and enhance fertility outcomes of aged follicles, as evidenced by human and rodent studies.

Anti-Müllerian hormone-mediated preantral follicle atresia is a key determinant of antral follicle count in mice

STUDY QUESTION

Does anti-Müllerian hormone (AMH) induce preantral follicle atresia in mice?

SUMMARY ANSWER

The present findings suggest that AMH-mediated follicle atresia only occurs in early follicles before they become sensitive to FSH.

WHAT IS KNOWN ALREADY

Most prior studies have investigated the ability of AMH to inhibit primordial follicle activation. Our previous study showed that AMH-overexpressing mice had fewer preantral follicles than expected after accounting for primordial follicle inhibition but the reason for this was not determined.

STUDY DESIGN, SIZE, DURATION

Cross-sectional-control versus transgenic/knockout mouse studies were carried out.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Studies were conducted on female wild-type (Amh+/+), AMH-knockout (Amh-/-) and AMH overexpressing (Thy1.2-AMHTg/0) mice on a C57Bl/6J background (age: 42-120 days). The follicle counts were conducted for primordial, transitioning, primary, secondary and antral follicles in Amh-/- and Amh+/+ mice. After confirming that follicle development speeds were identical (proliferating cell nuclear antigen immunohistochemistry), the ratio of follicles surviving beyond each stage of folliculogenesis was determined in both genotypes. Evidence for increased rates of preantral follicle atresia was assessed by active caspase-3 immunohistochemistry in wild-type and Thy1.2-AMHTg/0 mice.

MAIN RESULTS AND THE ROLE OF CHANCE

Amh -/- mice at 100-120 days of age had lower primordial follicle counts but higher primordial follicle activation rates compared to Amh+/+ mice. These counteracting effects led to equivalent numbers of primordial follicles transitioning to the primary stage in Amh+/+ and Amh-/- mice. Despite this, Amh+/+ mice had fewer primary, secondary, small antral and medium antral follicles than Amh-/- mice indicating differing rates of developing follicle atresia between genotypes. Cleaved caspase-3 immunohistochemistry in Thy1.2-AMHTg/0 ovaries revealed high rates of granulosa cell and oocyte apoptosis in late primary/early secondary follicles of Thy1.2-AMHTg/0 mice.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

The findings were shown only in one species and additional research will be required to determine generalizability to other species.

WIDER IMPLICATIONS OF THE FINDINGS

This study is consistent with prior studies showing that Amh-/- mice have increased primordial follicle activation but these new findings demonstrate that AMH-mediated preantral follicle atresia is a predominant cause of the increased small antral follicle counts in Amh-/- mice. This suggests that the role of AMH is not to conserve the ovarian reserve to prolong fertility, but instead to prevent the antral follicle pool from becoming too large. While this study may demonstrate a new function for AMH, the biological purpose of this function requires further investigation, particularly in mono-ovulatory species.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Health Research Council of New Zealand and the University of Otago. No competing interests to declare.

Knock-down of amh transcription by antisense RNA reduces FSH and increases follicular atresia in female Oreochromis niloticus

Anti-Müllerian hormone (Amh) plays an important role in regulating gonad development in teleosts. However, little is known about the effects of Amh on follicle development. In this study, we transfected the vector containing antisense RNA fragments of the amh gene to produce Nile tilapia, Oreochromis niloticus, with knocked-down Amh function in vivo. The results confirmed that the antisense RNA effectively inhibited amh transcription and Amh protein expression in female tilapia ovarian tissue. At 180 days of age, compared with control fish, female tilapia with knocked-down Amh function showed significantly increased growth and significantly decreased ovary weight and gonadosomatic index (P < 0.05). Female fish in the control group had ruddy-colored external genitalia, eggs extruded from the abdomen when gently squeezed, and most oocytes were developmental stage V. In contrast, the external genitalia of female fish with knocked-down Amh function did not have the ruddy color, no eggs extruded from the abdomen when squeezed, most oocytes were at developmental stages II and III, and considerable follicular atresia was apparent. At 180 days of age, the transcript levels of amhrII, cyp19a1a, foxl2 and sox9b in ovarian tissue, and the titers of luteinizing hormone, follicle stimulating hormone, and estradiol in the serum, were significantly lower in fish with knocked-down Amh function than in control fish (P < 0.05). We concluded that decreased serum hormone levels and an abnormal AMH signal delayed development and caused follicular degeneration in Nile tilapia with knocked-down Amh function. These findings show that antisense RNA is a feasible approach for gene silencing in fish, and represents an accurate and effective strategy to study gene function.

Role of anti-Mullerian hormone in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common gynecological endocrine disorders affecting up to 10% of all females in their reproductive age, and its cause of onset is still elusive. A spectrum of recent research reflected diverse associations between increased plasma level of anti-Mullerian hormone (AMH) and different clinical features of PCOS. Since AMH levels reflect the pool of growing follicles that potentially can ovulate, it can be stated that serum AMH levels can be used to assess the “functional ovarian reserve,” rather mentioning it as the “ovarian reserve.” AMH also appears to be a premier endocrine parameter for the assessment of atrophied ovarian follicular pool in response to age of individuals. AMH hinders the follicular development as well as the follicular recruitment and ultimately resulting in follicular arrest which is the key pathophysiologic condition for the onset of PCOS. Furthermore, FSH-induced aromatase activity remains inhibited by AMH that aids emergence of other associated clinical signs of PCOS, such as excess androgen, followed by insulin resistance among the PCOS individuals. Given the versatile association of AMH with PCOS and scarcity in literature explaining the underling mechanisms how AMH relates with PCOS, this review article will discuss the roles of AMH in the pathogenesis of PCOS which may introduce a new era in treatment approach of PCOS.

Fertility With Early Reduction of Ovarian Reserve

Female infertility is defined as the failure to conceive after a year of frequent, unprotected sexual activity. Infertility affects 8-10% of females worldwide. There are many causes of infertility. One of them is diminished ovarian reserve (DOR). In this condition, the ovary loses its reproductive potential, which affects fertility. This condition may be caused due to injury, but it usually results from aging. DOR is one of the main reasons for infertility in women worldwide. A woman with DOR has fewer eggs in her ovaries than usual. The quality of the remaining eggs may not be bad. This condition impairs the development of existing eggs. Patients with DOR may be able to get pregnant if they are properly treated according to their profile. Their treatments are individually tailored according to their needs. These patients should be recommended a robust approach toward treatment and increasing fertility. The chances of pregnancy increase if the treatment is started early.

Key signalling pathways underlying the aetiology of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine condition characterised by a range of reproductive, endocrine, metabolic and psychological abnormalities. Reports estimate that around 10% of women of reproductive age are affected by PCOS, representing a significant prevalence worldwide, which poses a high economic health burden. As the origin of PCOS remains largely unknown, there is neither a cure nor mechanism-based treatments leaving patient management suboptimal and focused solely on symptomatic treatment. However, if the underlying mechanisms underpinning the development of PCOS were uncovered then this would pave the way for the development of new interventions for PCOS. Recently, there have been significant advances in our understanding of the underlying pathways likely involved in PCOS pathogenesis. Key insights include the potential involvement of androgens, insulin, anti-Müllerian hormone and transforming growth factor beta in the development of PCOS. This review will summarise the significant scientific discoveries on these factors that have enhanced our knowledge of the mechanisms involved in the development of PCOS and discuss the impact these insights may have in shaping the future development of effective strategies for women with PCOS.

Anti-Müllerian Hormone Inhibits FSH-Induced Cumulus Oocyte Complex In Vitro Maturation and Cumulus Expansion in Mice

Anti-Müllerian hormone (AMH) is secreted by the ovaries of female animals and exerts its biological effects through the type II receptor (AMHR2). AMH regulates follicular growth by inhibiting the recruitment of primordial follicles and reducing the sensitivity of antral follicles to FSH. Despite the considerable research on the actions of AMH in granulosa cells, the effect of AMH on the in vitro maturation of oocytes remains largely unknown. In the current study, we showed that AMH is only expressed in cumulus cells, while AMHR2 is produced in both cumulus cells and oocytes. AMH had no significant effect on COCs nuclear maturation, whereas it inhibited the stimulatory effects of FSH on COCs maturation and cumulus expansion. Moreover, AMH treatment effectively inhibited the positive effect of FSH on the mRNA expressions of Hyaluronan synthase 2 (Has2), Pentraxin 3 (Ptx3), and TNF-alpha-induced protein 6 (Tnfaip 6) genes in COCs. In addition, AMH significantly decreased the FSH-stimulated progesterone production, but did not change estradiol levels. Taken together, our results suggest that AMH may inhibit the effects of FSH-induced COCs in vitro maturation and cumulus expansion. These findings increase our knowledge of the functional role of AMH in regulating folliculogenesis.

Chronic superphysiologic AMH promotes premature luteinization of antral follicles in human ovarian xenografts

Anti-Müllerian hormone (AMH) is produced by growing ovarian follicles and provides a diagnostic measure of reproductive reserve in women; however, the impact of AMH on folliculogenesis is poorly understood. We cotransplanted human ovarian cortex with control or AMH-expressing endothelial cells in immunocompromised mice and recovered antral follicles for purification and downstream single-cell RNA sequencing of granulosa and theca/stroma cell fractions. A total of 38 antral follicles were observed (19 control and 19 AMH) at long-term intervals (>10 weeks). In the context of exogenous AMH, follicles exhibited a decreased ratio of primordial to growing follicles and antral follicles of increased diameter. Transcriptomic analysis and immunolabeling revealed a marked increase in factors typically noted at more advanced stages of follicle maturation, with granulosa and theca/stroma cells also displaying molecular hallmarks of luteinization. These results suggest that superphysiologic AMH alone may contribute to ovulatory dysfunction by accelerating maturation and/or luteinization of antral-stage follicles.

Polycystic Ovarian Syndrome: A Complex Disease with a Genetics Approach

Polycystic ovarian syndrome (PCOS) is a complex endocrine disorder affecting females in their reproductive age. The early diagnosis of PCOS is complicated and complex due to overlapping symptoms of this disease. The most accepted diagnostic approach today is the Rotterdam Consensus (2003), which supports the positive diagnosis of PCOS when patients present two out of the following three symptoms: biochemical and clinical signs of hyperandrogenism, oligo, and anovulation, also polycystic ovarian morphology on sonography. Genetic variance, epigenetic changes, and disturbed lifestyle lead to the development of pathophysiological disturbances, which include hyperandrogenism, insulin resistance, and chronic inflammation in PCOS females. At the molecular level, different proteins and molecular and signaling pathways are involved in disease progression, which leads to the failure of a single genetic diagnostic approach. The genetic approach to elucidate the mechanism of pathogenesis of PCOS was recently developed, whereby four phenotypic variances of PCOS categorize PCOS patients into classic, ovulatory, and non-hyperandrogenic types. Genetic studies help to identify the root cause for the development of this PCOS. PCOS genetic inheritance is autosomal dominant but the latest investigations revealed it as a multigene origin disease. Different genetic loci and specific genes have been identified so far as being associated with this disease. Genome-wide association studies (GWAS) and related genetic studies have changed the scenario for the diagnosis and treatment of this reproductive and metabolic condition known as PCOS. This review article briefly discusses different genes associated directly or indirectly with disease development and progression.

Synergistic Regulatory Effect of Inhibin and Anti-Müllerian Hormone on Fertility of Mice

Inhibin (INH) and anti-Müllerian hormone (AMH) are essential in ovarian folliculogenesis and play an inhibitory role in mammalian fertility. However, the interactive effect of INH and AMH on the animal reproduction remains unknown. This study aimed to determine the possible interaction and synergy between INH and AMH in steroidogenesis by primary granulosa cells, and investigate their synergistic effect on fertility in mice. In in vitro granulosa cell culture system, we found that the treatment of either INHA or AMH had no significant effect on basal estradiol and progesterone production, whereas both significantly attenuated FSH-induced steroid hormone secretion. Importantly, combined treatment with INHA and AMH showed additive inhibitory effect on FSH-induced estradiol and progesterone production, accompanying a significant downregulation in the expression of FSH-stimulated CYP19A1, HSD3B, CYP11A1, StAR transcripts. The interrelationship of INH and AMH combinations was further investigated through active immune neutralization strategy. Female mice were immunized against INH and AMH eukaryotic expression plasmids, and the litter size was recorded after successfully mating. We observed that both INH and AMH plasmids were able to induce either anti-AMH or anti-INH antibodies in the immunized mice. In comparison with the control group, co-immunization with INH and AMH plasmids induced higher levels of estradiol, resulting in more litter size. Moreover, there was no significant difference on the offspring's weight between each group. Collectively, the results of the present study suggest that INH and AMH have synergistic effect in regulating steroidogenesis and the litter size in mice.

Anti-Müllerian Hormone in Female Reproduction

Anti-Müllerian hormone (AMH), also called Müllerian inhibiting substance, was shown to be synthesized by the ovary in the 1980s. This article reviews the main findings of the past 20 years on the regulation of the expression of AMH and its specific receptor AMHR2 by granulosa cells, the mechanism of action of AMH, the different roles it plays in the reproductive organs, its clinical utility, and its involvement in the principal pathological conditions affecting women. The findings in respect of regulation tell us that AMH and AMHR2 expression is mainly regulated by bone morphogenetic proteins, gonadotropins, and estrogens. It has now been established that AMH regulates the different steps of folliculogenesis and that it has neuroendocrine effects. On the other hand, the importance of serum AMH as a reliable marker of ovarian reserve and as a useful tool in the prediction of the polycystic ovary syndrome (PCOS) and primary ovarian failure has also been acknowledged. Last but not least, a large body of evidence points to the involvement of AMH in the pathogenesis of PCOS.

Functional Activity of Recombinant Forms of Amh and Synergistic Action with Fsh in European Sea Bass Ovary

Although anti-Müllerian hormone (AMH) has classically been correlated with the regression of Müllerian ducts in male mammals, involvement of this growth factor in other reproductive processes only recently come to light. Teleost is the only gnathostomes that lack Müllerian ducts despite having amh orthologous genes. In adult teleost gonads, Amh exerts a role in the early stages of germ cell development in both males and females. Mechanisms involving the interaction of Amh with gonadotropin- and growth factor-induced functions have been proposed, but our overall knowledge regarding Amh function in fish gonads remains modest. In this study, we report on Amh actions in the European sea bass ovary. Amh and type 2 Amh receptor (Amhr2) are present in granulosa and theca cells of both early and late-vitellogenic follicles and cannot be detected in previtellogenic ovaries. Using the Pichia pastoris system a recombinant sea bass Amh has been produced that is endogenously processed to generate a 12–15 kDa bioactive mature protein. Contrary to previous evidence in lower vertebrates, in explants of previtellogenic sea bass ovaries, mature Amh has a synergistic effect on steroidogenesis induced by the follicle-stimulating hormone (Fsh), increasing E2 and cyp19a1a levels.

Translational Physiology of Anti-Müllerian Hormone: Clinical Applications in Female Fertility Preservation and Cancer Treatment

Background

Whilst the ability of AMH to induce the regression of the Müllerian ducts in the male fetus is well appreciated, AMH has additional biological actions in relation to steroid biosynthesis and ovarian follicle dynamics. An understanding of the physiology of AMH illuminates the potential therapeutic utility of AMH to protect the ovarian reserve during chemotherapy and in the treatment of female malignancies. The translation of the biological actions of AMH into clinical applications is an emerging focus of research, with promising preliminary results.

Objective and Rationale

Studies indicate AMH restrains primordial follicle development, thus administration of AMH during chemotherapy may protect the ovarian reserve by preventing the mass activation of primordial follicles. As AMH induces regression of tissues expressing the AMH receptor (AMHRII), administration of AMH may inhibit growth of malignancies expressing AMHR II. This review evaluates the biological actions of AMH in females and appraises human clinical applications.

Search Methods

A comprehensive search of the Medline and EMBASE databases seeking articles related to the physiological functions and therapeutic applications of AMH was conducted in July 2021. The search was limited to studies published in English.

Outcomes

AMH regulates primordial follicle recruitment and moderates sex steroid production through the inhibition of transcription of enzymes in the steroid biosynthetic pathway, primarily aromatase and 17α-hydroxylase/17,20-lyase. Preliminary data indicates that administration of AMH to mice during chemotherapy conveys a degree of protection to the ovarian reserve. Administration of AMH at the time of ovarian tissue grafting has the potential to restrain uncontrolled primordial follicle growth during revascularization. Numerous studies demonstrate AMH induced regression of AMHR II expressing malignancies. As this action occurs via a different mechanism to traditional chemotherapeutic agents, AMH has the capacity to inhibit proliferation of chemo-resistant ovarian cancer cells and cancer stem cells.

Wider Implications

To date, AMH has not been administered to humans. Data identified in this review suggests administration of AMH would be safe and well tolerated. Administration of AMH during chemotherapy may provide a synchronistic benefit to women with an AMHR II expressing malignancy, protecting the ovarian reserve whilst the cancer is treated by dual mechanisms.

High serum anti-Müllerian hormone concentrations have a negative impact on fertilization and embryo development rates

RESEARCH QUESTION

What is the impact of high serum anti-Müllerian hormone (AMH) concentrations on fertilization and embryo development among infertile women undergoing treatment with assisted reproductive technology (ART)?

DESIGN

Retrospective study of 1036 infertile women undergoing ART; women were divided into three groups according to serum AMH concentrations: AMH <1.1 ng/ml, 1.1-5.0 ng/ml and >5.0 ng/ml. The fertilization and embryo development rates of patients with different AMH concentrations and after stratification according to age were compared.

RESULTS

Women with high AMH concentrations were younger and had higher testosterone concentrations (0.4 ± 0.13 versus 0.3 ± 0.12 versus 0.3 ± 0.08 µg/dl, P < 0.001) than women with low AMH concentrations. However, analysis of the embryo development rate showed negative outcomes for women with high AMH concentrations, including a poor fertilization rate (76.3 ± 17.36 versus 82.1 ± 19.15 versus 82.4 ± 25.38, P = 0.003), and poor day 3 embryo development rate (55.6 ± 23.88 versus 62.6 ± 26.52 versus 62.8 ± 32.65, P = 0.014). Multivariate linear regression analysis showed significantly negative correlations of the AMH concentrations with the fertilization rate (P < 0.001) and day 3 embryo development rate (P = 0.006). Subgroup analysis showed that age 30 years or younger had a significant negative correlation with AMH and the embryo development rate, including the fertilization rate (P < 0.001) and day 3 embryo development rate (P = 0.037).

CONCLUSION

These results suggest that high serum AMH concentrations, contributing to a hyperandrogenic environment and leading to decreased oocyte developmental competence, may have a negative impact on fertilization and the early stage of embryo development in women undergoing treatment with ART.

Randomized Controlled Trial of Neurokinin 3 Receptor Antagonist Fezolinetant for Treatment of Polycystic Ovary Syndrome

CONTEXT

Polycystic ovary syndrome (PCOS), a highly prevalent endocrine disorder characterized by hyperandrogenism, is the leading cause of anovulatory infertility.

OBJECTIVE

This proof-of-concept study evaluated clinical efficacy and safety of the neurokinin 3 (NK3) receptor antagonist fezolinetant in PCOS.

METHODS

This was a phase 2a, randomized, double-blind, placebo-controlled, multicenter study (EudraCT 2014-004409-34). The study was conducted at 5 European clinical centers. Women with PCOS participated in the study. Interventions included fezolinetant 60 or 180 mg/day or placebo for 12 weeks. The primary efficacy end point was change in total testosterone. Gonadotropins, ovarian hormones, safety and tolerability were also assessed.

RESULTS

Seventy-three women were randomly assigned, and 64 participants completed the study. Adjusted mean (SE) changes in total testosterone from baseline to week 12 for fezolinetant 180 and 60 mg/day were -0.80 (0.13) and -0.39 (0.12) nmol/L vs -0.05 (0.10) nmol/L with placebo (P < .001 and P < .05, respectively). Adjusted mean (SE) changes from baseline in luteinizing hormone (LH) for fezolinetant 180 and 60 mg/d were -10.17 (1.28) and -8.21 (1.18) vs -3.16 (1.04) IU/L with placebo (P < .001 and P = .002); corresponding changes in follicle-stimulating hormone (FSH) were -1.46 (0.32) and -0.92 (0.30) vs -0.57 (0.26) IU/L (P = .03 and P = .38), underpinning a dose-dependent decrease in the LH-to-FSH ratio vs placebo (P < .001). Circulating levels of progesterone and estradiol did not change significantly vs placebo (P > .10). Fezolinetant was well tolerated.

CONCLUSION

Fezolinetant had a sustained effect to suppress hyperandrogenism and reduce the LH-to-FSH ratio in women with PCOS.

Ovarian Reserve Biomarkers and Menstrual Cycle Length in a Prospective Cohort Study

CONTEXT

While age-related changes in menstrual cycle length are well known, it is unclear whether anti-Müllerian (AMH) or other ovarian reserve biomarkers have a direct association with cycle length.

OBJECTIVE

To determine the association between biomarkers of ovarian reserve and menstrual cycle length.

METHODS

Secondary analysis using data from time to conceive (TTC), a prospective time to pregnancy cohort study. The age-independent association between cycle length and biomarkers of ovarian reserve was analyzed using linear mixed and marginal models. Study participants were TTC-enrolled women aged 30-44 years with no history of infertility who were attempting to conceive for <3 months were enrolled. Serum AMH, follicle-stimulating hormone, and inhibin B levels were measured on cycle day 2, 3, or 4. Participants recorded daily menstrual cycle data for ≤4 months. The primary outcome was menstrual cycle length; follicular and luteal phase lengths were secondary outcomes.

RESULTS

Multivariable analysis included 1880 cycles from 632 women. Compared with AMH levels of 1.6 to 3.4 ng/mL, women with AMH <1.6 ng/mL had cycles and follicular phases that were 0.98 (95% CI -1.46, -0.50) and 1.58 days shorter (95% CI -2.53, -0.63), respectively, while women with AMH >8 ng/mL had cycles that were 2.15 days longer (95% CI 1.46, 2.83), follicular phases that were 2 days longer (95% CI 0.77, 3.24), and luteal phases that were 1.80 days longer (95% CI 0.71, 2.88).

CONCLUSION

Increasing AMH levels are associated with longer menstrual cycles due to both a lengthening of the follicular and the luteal phase independent of age.

Reduced FSH and LH action: implications for medically assisted reproduction

Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) play complementary roles in follicle development and ovulation via a complex interaction in the hypothalamus, anterior pituitary gland, reproductive organs, and oocytes. Impairment of the production or action of gonadotropins causes relative or absolute LH and FSH deficiency that compromises gametogenesis and gonadal steroid production, thereby reducing fertility. In women, LH and FSH deficiency is a spectrum of conditions with different functional or organic causes that are characterized by low or normal gonadotropin levels and low oestradiol levels. While the causes and effects of reduced LH and FSH production are very well known, the notion of reduced action has received less attention by researchers. Recent evidence shows that molecular characteristics, signalling as well as ageing, and some polymorphisms negatively affect gonadotropin action. These findings have important clinical implications, in particular for medically assisted reproduction in which diminished action determined by the afore-mentioned factors, combined with reduced endogenous gonadotropin production caused by GnRH analogue protocols, may lead to resistance to gonadotropins and, thus, to an unexpected hypo-response to ovarian stimulation. Indeed, the importance of LH and FSH action has been highlighted by the International Committee for Monitoring Assisted Reproduction Technologies (ICMART) in their definition of hypogonadotropic hypogonadism as gonadal failure associated with reduced gametogenesis and gonadal steroid production due to reduced gonadotropin production or action. The aim of this review is to provide an overview of determinants of reduced FSH and LH action that are associated with a reduced response to ovarian stimulation.

Comparison of Human Antral Follicles of Xenograft versus Ovarian Origin Reveals Disparate Molecular Signatures

The activation, growth, and maturation of oocytes to an ovulatory phase, termed folliculogenesis, is governed by the orchestrated activity of multiple specialized cell types within the ovary; yet, the mechanisms governing diversification and behavior of discrete cellular sub-populations within follicles are poorly understood. We use bulk and single-cell RNA sequencing to distinguish the transcriptional signature of prospectively isolated granulosa and theca/stroma cell subsets within human antral follicles derived from xenografts or ovaries. The analysis deconstructs phenotypic diversification within small (<4 mm) antral follicles, identifying secreted factors that are differentially enriched between mural and oophorus granulosa cells, and segregating stromal/support and steroidal activity between theca externa and interna, respectively. Multiple factors are differentially expressed in follicles of xenograft versus ovarian origin. These data capture a high-resolution transcriptional signature of granulosa and theca subpopulations and provide a systems-level portrait of cellular diversification in early antral human follicles.

Interactions between serum FSH, inhibin B and antral follicle count in the decline of serum AMH during the menstrual cycle in late reproductive age

Objective

To investigate the hormonal interrelationships during the menstrual cycle in women of late reproductive age with suppressed serum AMH and antral follicle count (AFC).

Methods

Serum hormones (AMH, FSH, LH, estradiol, progesterone, inhibin A, inhibin B), AFC (2-10 mm) and AMH/AFC ratio (an estimate of AMH/follicle) were assessed every 2-3 days across the menstrual cycle in 26 healthy ovulatory women aged 18-50 years.

Results

An 11-fold fall in AMH/AFC was observed in women aged ≥45 years compared to those 18-45 years (P < .001). Although women ≥45 years exhibited normal menstrual cycle patterns of serum estradiol, progesterone, LH and inhibin A, FSH was elevated (P < .001) and inhibin B suppressed (P < .001) compared to the younger group. Overall FSH was inversely correlated (r = .55, P < .05) and AMH directly correlated (r = .88, P < .01) with AFC; however, these relationships were curvilinear and more pronounced when AFC was low. Inhibin B was directly linearly correlated (r = .70, P < .01) with AFC across both high and low AMH/follicle groups.

Conclusions

It is hypothesized that the marked fall in AMH/follicle in late reproductive age is attributed to the change in the hormonal interplay between the pituitary and ovary. The fall in AFC leads to a decrease in inhibin B and a concomitant increase in FSH by a recognized feedback mechanism. It is postulated the elevated FSH suppresses AMH either directly or indirectly through oocyte-specific growth factors leading to a marked fall in AMH/follicle. We propose that pituitary-ovarian and intra-ovarian regulatory systems underpin the accelerated fall in AMH/follicle during the transition to menopause.

New Anti-Müllerian Hormone Target Genes Involved in Granulosa Cell Survival in Women With Polycystic Ovary Syndrome

PURPOSE

A protective effect of anti-Müllerian hormone (AMH) on follicle atresia was recently demonstrated using long-term treatments, but this effect has never been supported by mechanistic studies. This work aimed to gain an insight into the mechanism of action of AMH on follicle atresia and on how this could account for the increased follicle pool observed in women with polycystic ovary syndrome (PCOS).

METHODS

In vivo and in vitro experiments were performed to study the effects of AMH on follicle atresia and on the proliferation and apoptosis of granulosa cells (GCs). RNA-sequencing was carried out to identify new AMH target genes in GCs. The expression of some of these genes in GCs from control and PCOS women was compared using microfluidic real time quantitative RT-PCR.

RESULTS

A short-term AMH treatment prevented follicle atresia in prepubertal mice. Consistent with this result, AMH inhibited apoptosis and promoted proliferation of different models of GCs. Moreover, integrative biology analyses of 965 AMH target genes identified in 1 of these GC models, confirmed that AMH had initiated a gene expression program favoring cell survival and proliferation. Finally, on 43 genes selected among the most up- and down-regulated AMH targets, 8 were up-regulated in GCs isolated from PCOS women, of which 5 are involved in cell survival.

MAIN CONCLUSIONS

Our results provide for the first time cellular and molecular evidence that AMH protects follicles from atresia by controlling GC survival and suggest that AMH could participate in the increased follicle pool of PCOS patients.

The endocrine milieu in naturally matured follicles is different in women with high serum anti-Müllerian hormone concentrations

RESEARCH QUESTION

Is the endocrine milieu different in women with low serum anti-Müllerian hormone (AMH) concentration compared with women with high concentration?

DESIGN

Cohort study of 84 women (four groups) classified according to AMH concentration and age undergoing natural cycle IVF treatment. Concentrations of LH, oestradiol, testosterone, androstenedione and AMH were determined in follicular fluid (FF), associations analysed and clinical outcome parameters evaluated.

RESULTS

A positive correlation between serum and FF AMH concentrations was confirmed. Follicular fluid androstenedione concentration was positively correlated with serum AMH concentration (P < 0.0001, r² = 0.197). The correlation between FF LH and FF testosterone concentration in all women was not significant (P = 0.050, r² = 0.046); however, the correlation between FF androstenedione in women with high serum AMH concentration was significant (P = 0.032, r² = 0.220). Follicular fluid testosterone and androstenedione were positively correlated with FF oestradiol overall and in some individual groups. The high serum AMH concentration group showed the highest FF AMH and androstenedione concentrations and lowest oestradiol-testosterone and oestradiol-androstenedione ratios. High FF AMH concentration was associated with a higher clinical pregnancy rate and high FF oestradiol concentration with a slightly better embryo quality.

CONCLUSIONS

Differences in the endocrine milieu in women with high serum AMH concentration seem to be caused by increased follicular LH concentration. In women with high serum AMH concentration, FF androstenedione is increased and ratios of oestradiol-testosterone and oestradiol-androstenedione are decreased, suggesting a disturbed endocrine milieu caused by reduced metabolization of FF androgens into oestrogens. In natural cycles, FF AMH concentrations are positively associated with higher clinical pregnancy rates and oestradiol concentrations with a higher embryo score.

FSHB Transcription is Regulated by a Novel 5' Distal Enhancer With a Fertility-Associated Single Nucleotide Polymorphism

The pituitary gonadotropins, follicle-stimulating hormone (FSH) and luteinizing hormone, signal the gonads to regulate male and female fertility. FSH is critical for female fertility as it regulates oocyte maturation, ovulation, and hormone synthesis. Multiple genome-wide association studies (GWAS) link a 130 Kb locus at 11p14.1, which encompasses the FSH beta-subunit (FSHB) gene, with fertility-related traits that include polycystic ovary syndrome, age of natural menopause, and dizygotic twinning. The most statistically significant single nucleotide polymorphism from several GWAS studies (rs11031006) resides within a highly conserved 450 bp region 26 Kb upstream of the human FSHB gene. Given that sequence conservation suggests an important biological function, we hypothesized that the region could regulate FSHB transcription. In luciferase assays, the conserved region enhanced FSHB transcription and gel shifts identified a binding site for Steroidogenic factor 1 (SF1) contributing to its function. Analysis of mouse pituitary single-cell ATAC-seq demonstrated open chromatin at the conserved region exclusive to a gonadotrope cell-type cluster. Additionally, enhancer-associated histone markers were identified by immunoprecipitation of chromatin from mouse whole pituitary and an immortalized mouse gonadotrope-derived LβT2 cell line at the conserved region. Furthermore, we found that the rs11031006 minor allele upregulated FSHB transcription via increased SF1 binding to the enhancer. All together, these results identify a novel upstream regulator of FSHB transcription and indicate that rs11031006 can modulate FSH levels.

High Variability of Molecular Isoforms of AMH in Follicular Fluid and Granulosa Cells From Human Small Antral Follicles

Anti-Müllerian hormone (AMH) is a member of the TGF-β superfamily produced by follicular granulosa cells (GCs) in women from late gestation to the end of reproductive life. AMH is thought to inhibit aromatase (i.e., CYP19) expression and decrease the conversion of androgens to oestrogens, especially in small antral follicles before dominance is achieved. Thus, AMH acts as a gatekeeper of ovarian steroidogenesis. However, the exact function and processing of AMH has not been fully elucidated. The present study measured and determined AMH isoforms in human follicular fluid (FF) from small antral follicles and in human GCs using four ELISAs, western blot, and immunofluorescence analysis. We evaluated the presence of the following isoforms: full-length AMH precursor (proAMH), cleaved associated AMH (AMH_N,C), N-terminal pro-region (AMH_N), and active C-terminal (AMH_C) AMH. A negative correlation between follicle diameter and the AMH forms was detected. Moreover, western blot analysis detected various AMH forms in both FFs and GCs, which did not match our consensus forms, suggesting an unknown proteolytic processing of AMH. The presence of these new molecular weight isoforms of AMH differs between individual follicles of identical size in the same woman. This study detected several AMH forms in FF and GCs obtained from human small antral follicles, which suggests that intrafollicular processing of AMH is complex and variable. Thus, it may be difficult to develop an antibody-based AMH assay that detects all AMH isoforms. Furthermore, the variability between follicles suggests that designing a recombinant AMH standard will be difficult.

Effect of anti-müllerian hormone on the development and selection of ovarian follicle in hens

To elucidate the role of anti-müllerian hormone (AMH) in regulating the development of ovarian follicles in laying hens, the expressions of follicle-stimulating hormone receptor (FSHR), AMH receptor type 2 (AMHR2), steroidogenic-related genes steroidogenic acute regulatory protein (STAR), cytochrome P450 side-chain cleavage (CYP11A1), and 3β-hydroxysteroid dehydrogenase (HSD3B1) genes were measured from different sized follicles and granulosa cells. The results showed that the expressions of FSHR and AMHR2 genes were higher in small follicles and decreased after follicular selection. Oppositely, the expressions of STAR, CYP11A1, and HSD3B1 were significantly increased after follicular selection. It indicated that AMHR2 might mediate AMH suppression in the stimulating effects of follicle-stimulating hormone (FSH) on steroidogenic-related genes expression. To make sure the effects of AMH in this process, a total of 40 hens were treated (negative control, sham operation, 150 ng AMH/d or 300 ng AMH/d) for 25 d. We analyzed ovarian morphology, progesterone concentration in blood plasma, and the expressions of steroidogenic genes in ovaries and follicles. The AMH300 group had significantly lower weight of ovary and hierarchical follicles. Egg weight and ovary weight in AMH150 group were higher than those of sham operation and AMH300 groups, so did hierarchical follicles weight. The steroidogenic genes expressions showed an increase in ovarian tissue and the largest follicle of AMH150 and AMH300 groups. However, progesterone level in the blood was reduced by AMH injection with different concentrations. To further verify the above results, granulosa cells from 6 to 8 mm follicles were cultured with AMH (0, 5, 10, 20, 40, or 80 ng/mL). The results revealed that excessive AMH (80 ng/mL) exerted an inhibitory effect on progesterone synthesis and the expressions of STAR, CYP11A1, and HSD3B1. However, these genes expressions showed a significant increase in 20 ng/mL AMH-treated group. In summary, AMH inhibited the development of prehierarchical follicles in laying hens. The effects of AMH treatment with different concentrations on follicle development showed the follicle was selected by changing FSH responsiveness of prehierarchical follicles.

Genetic evidence for Amh modulation of gonadotropin actions to control gonadal homeostasis and gametogenesis in zebrafish and its noncanonical signaling through Bmpr2a receptor

Anti-Müllerian hormone (Amh) plays an important role in gonadal function. Amh deficiency causes severe gonadal dysgenesis and dysfunction in zebrafish, with gonadal hypertrophy in both sexes. However, its mechanism of action remains unknown. Intriguingly, the Amh cognate type II receptor (Amhr2) is missing in the zebrafish genome, in sharp contrast to other species. Using a series of zebrafish mutants (amh, fshb, fshr and lhcgr), we provided unequivocal evidence for actions of Amh, via modulation of gonadotropin signaling, on both germ cell proliferation and differentiation. The gonadal hypertrophy in amh mutants was abolished in the absence of Fshr in females or Fshr/Lhcgr in males. Furthermore, we demonstrated that knockout of bmpr2a, but not bmpr2b, phenocopied all phenotypes of the amh mutant in both sexes, including gonadal hypertrophy, hyperproliferation of germ cells, retarded gametogenesis and reduced fshb expression. In summary, the present study provided comprehensive genetic evidence for an intimate interaction of gonadotropin and Amh pathways in gonadal homeostasis and gametogenesis and for Bmpr2a as the possible missing link for Amh signaling in zebrafish.

Mining of variables from embryo morphokinetics, blastocyst's morphology and patient parameters: an approach to predict the live birth in the assisted reproduction service

Based on growing demand for assisted reproduction technology, improved predictive models are required to optimize in vitro fertilization/intracytoplasmatic sperm injection strategies, prioritizing single embryo transfer. There are still several obstacles to overcome for the purpose of improving assisted reproductive success, such as intra- and inter-observer subjectivity in embryonic selection, high occurrence of multiple pregnancies, maternal and neonatal complications. Here, we compare studies that used several variables that impact the success of assisted reproduction, such as blastocyst morphology and morphokinetic aspects of embryo development as well as characteristics of the patients submitted to assisted reproduction, in order to predict embryo quality, implantation or live birth. Thereby, we emphasize the proposal of an artificial intelligence-based platform for a more objective method to predict live birth.

Role of anti-Müllerian hormone and testosterone in follicular growth: a cross-sectional study

BACKGROUND

Anti-Müllerian hormone (AMH) is now considered the best serum biomarker of ovarian reserve, while basal sex hormones are classic markers used for assessing ovarian reserve. The interaction between AMH and sex hormones are complicated and not sufficiently addressed. In this study, we took diminished ovarian reserve (DOR) and polycystic ovarian syndrome (PCOS) as two extremes of ovarian reserve (deficient and excessive respectively) to investigate the role of AMH and sex hormones in follicular growth.

METHODS

A retrospective cross-sectional survey was performed. The patients assessed AMH and basal sex hormones in the Second Hospital of Zhejiang University from April 2016 to March 2019 were involved in this study. Serum AMH and sex hormone concentrations were tested with electrochemiluminescence method. Stepwise linear regression and binary logistic regression was used to determine the predictors of AMH level and to explore the involved factors determining DOR and PCOS.

RESULTS

In the present study, we found that age and follicle-stimulating hormone (FSH) were main negative correlation factors, and luteinizing hormone (LH) and testosterone (T) were main positive factors of AMH. In DOR group, age, FSH and estradiol (E₂) increased and T decreased, while in PCOS group, LH and T increased. Binary logistic regression found that age, weight, FSH, E₂, and T were the significant factors which independently predicted the likelihood of DOR, and that age, body mass index (BMI), AMH, LH, and T predicted the likelihood of PCOS.

CONCLUSIONS

Our study demonstrated that age, FSH, and T were factors that most closely correlated with AMH level, and T was involved in both DOR and PCOS. Since DOR and PCOS are manifested with insufficient AMH and excessive AMH respectively, it is suggested that total testosterone correlated with AMH closely and plays an important role in follicular growth. More attention should be given to testosterone level during controlled ovarian hyperstimulation (COH) process.

Recombinant Anti-Müllerian Hormone (rAMH) for Stalling In Vitro Granulosa Cell Replication

To investigate whether recombinant AMH (rAMH) is able to decrease cellular proliferation/apoptosis in luteinized granulosa cells (GCs) through hormonal regulation, a primary culture of GCs was established from GCs obtained at time of oocyte retrieval from follicular fluid of 3 patients. Cells were seeded in well cell culture plates at a density of 100,000 cells/well in medium and treated with rAMH 20 ng/ml (rAMH group), or phosphate-buffered saline (PBS-control group), for 24 h. Total RNA was extracted from all cells, followed by cDNA synthesis and real-time RT-PCR to quantify the expression levels of AMH, AMH-R2, FSH-R, inhibin B, cell proliferation (Ki67), and apoptosis (Caspase 3). We used independent sample t test (SPSS v25) and a p < 0.05 significance. Cellular expressions of AMH, AMH-R2, FSH-R, and inhibin B were reduced greater than 50% in the rAMH group, compared with that of the the control group (p ≤ 0.005 for all). Ki67 and Caspase3 were also reduced greater than 30% in the rAMH group (p ≤ 0.001 for both). Our findings show a direct inhibitory effect of AMH on luteinized GCs' expression of the major regulatory hormones, in addition to a significant decrease in markers of cell proliferation and apoptosis. These results confirm the inhibitory effects of AMH on follicular development.

Utilising FGF2, IGF2 and FSH in serum-free protocol for long-term in vitro cultivation of primary human granulosa cells

Human granulosa cells acquired as leftover from IVF treatment can be used to study infertility problems and are a valuable tool in the research of follicle maturation and ovulation. There is a need for more defined and long-term culture protocols for studying the response of granulosa cells upon treatment with selected hormones/chemicals. In the current study, we tested the effect of adding FGF2, IGF2 and FSH into defined basal medium in order to find culture conditions that would support proliferation of cumulus and mural granulosa cells along with the expression of common granulosa cell type markers such as FSHR, AMHR2, LHR and CYP19A1. We found that FGF2, IGF2 together with FSH helped to retain granulosa cell marker expression while supporting cell survival at least for two weeks of culture. The defined serum-free culture conditions for long-term culturing will be valuable in providing new standards in the research of human granulosa cells.

Virus analog decreases estradiol secretion in FSH-treated human ovarian granulosa cells

The aim of this study was to evaluate the effect of virus infection on estradiol (E₂) production in human ovarian granulosa cells. Polyriboinosinic polyribocytidylic acid [Poly (I: C)], a synthetic analog of viral double stranded RNA that can be recognized by Toll like receptor 3 (TLR3), was used to imitate virus infection. Granulosa cells (GCs) obtained from patients undergoing in vitro fertilization and embryo transfer (IVF-ET) were cultured in vitro and treated with Poly (I: C), FSH, or both. Concentration of E₂ was assayed by electrochemiluminescence. The mRNA and protein expression of TLR3 and aromatase were determined by real-time quantitative PCR (qPCR) and Western blot, respectively. The results showed that expression of TLR3 mRNA was significantly increased after Poly (I: C) stimulation. Poly (I: C) decreased E₂ synthesis in FSH-treated GCs. Poly (I: C) inhibited the expression of aromatase in FSH-treated GCs. This study demonstrated that Poly (I: C) inhibits the synthesis of estradiol by granulosa cells under the stimulation of FSH, which might contribute to disturbance of follicular development and ovulation.

High serum Antimullerian hormone levels are associated with lower live birth rates in women with polycystic ovarian syndrome undergoing assisted reproductive technology

INTRODUCTION

Antimullerian hormone (AMH) strongly correlates with ovarian reserve and response to controlled ovarian stimulation. Emerging data suggests that serum AMH level may also predict ART outcomes. However, AMH is characteristically elevated in PCOS women and it is unknown whether it may predict live birth outcomes in this population.

METHODS

This was a retrospective cohort study of 184 PCOS women (Rotterdam criteria) who underwent their first fresh IVF/ICSI cycle. Women were divided into 3 groups according to the <25th (low), 25 to 75th (average), or > 75th (high) percentile of serum AMH concentration. Cycle stimulation parameters and reproductive outcomes were compared between groups.

RESULTS

Women in the low serum AMH group were older than those in the average or high AMH (p < 0.05), and required greater gonadotropin dose for stimulation compared to the high AMH group (p < 0.05). Women with high AMH had greater testosterone level compared to women in the low or average AMH groups. No differences were noted between groups in terms of maximal E2, oocytes retrieved and fertilization rate. However, low serum AMH women had significantly greater live birth rates (p < 0.05) and showed a trend towards greater clinical pregnancy rates compared to women in the average and high AMH groups (p = 0.09). The significant association of AMH with live birth rate remained after adjusting for age, BMI, day of transfer and number of embryos transferred.

CONCLUSIONS

In PCOS women, elevated AMH concentrations are associated with hyperandrogenism and lower live birth rates.

Active immunization against AMH reveals its inhibitory role in the development of pre-ovulatory follicles in Zhedong White geese

The aim of this study was to investigate the effects of active immunization against recombinant Anti-Müllerian hormone (AMH) protein on the ovarian follicular development, egg production, and molecular regulatory mechanisms in broody-prone Zhedong White geese. For this, a recombinant goose AMH protein was expressed using a prokaryotic expression system. Fifty incubating geese from the same genetic background were selected and equally divided into two groups. The immunization group was actively immunized against the recombinant goose AMH protein, whereas the control group was immunized against bovine serum albumin (BSA). Immunization against AMH accelerated ovarian follicular development and increased clutch sizes by one to two eggs in two consecutive laying-incubation cycles. Furthermore, immunization against AMH upregulated the mRNA transcription levels of the FSH-beta gene in the pituitary gland, and FSHR, 3beta-HSD, and Smad4 genes in the granulosa layer of pre-ovulatory follicles; however, immunization downregulated the expression of the OCLN gene in the granulosa layer of pre-ovulatory follicles, and Smad5 and Smad9 genes in the granulosa layer of SYFs. These results suggest that AMH might hinder ovarian follicular development by decreasing both pituitary FSH secretion as well as ovarian follicular sensitivity to FSH. The latter molecular mechanism could be fulfilled by regulating Smad5 or Smad9 signals in SYFs, as well as the FSHR and Smad4 signals that affect progesterone synthesis and yolk deposition in the pre-ovulatory follicles.

Primary immunoprevention of adult onset cancers by vaccinating against retired tissue-specific self-proteins

Despite the enormous success of childhood prophylactic vaccination against diseases caused by pathogens, there is currently no similar preventive vaccine program against diseases confronted with age like breast cancer and ovarian cancer. With the exception of the annual influenza vaccine, current recommendations for adult vaccination are for either primary vaccines not received during childhood or for booster vaccinations to maintain the immunity against pathogens already induced during childhood. Here we describe a strategy to provide prophylactic pre-emptive immunity against the development of adult onset cancers not associated with any definitive etiopathogenic agent. We propose that safe and effective pre-emptive immunity may be induced in cancer-free subjects by vaccination against immunodominant tissue-specific self-proteins that are 'retired' from expression in normal tissues as part of the normal aging process but are expressed in tumors that emerge with age. Primary immunoprevention of adult onset cancers like breast cancer and ovarian cancer represents a great challenge and an even greater unmet need for our current healthcare.

MiR-29a regulates the proliferation, aromatase expression, and estradiol biosynthesis of human granulosa cells in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common cause of anovulatory infertility in reproductive-aged women; however, its etiology remains poorly understood. This study aimed to reveal the role of miR-29a in PCOS. MiR-29a levels were measured in the granulosa cells (GCs) of forty-seven PCOS patients and forty-seven controls. A receiver operating characteristic (ROC) curve was drawn to evaluate the diagnostic value of miR-29a in non-hyperandrogenism PCOS. MiR-29a was overexpressed in KGN and COV434 cells to examine its roles in proliferation, cell-cycle progression, and steroidogenesis. MiR-29a was significantly down-regulated in PCOS patients, and associated with an increased antral follicle count. The ROC curve showed a major separation between PCOS patients and controls. MiR-29a overexpression in KGN and COV434 cells inhibited cell proliferation, arrested cell-cycle progression, and decreased aromatase expression and estradiol production. These findings suggest that miR-29a is involved in GC proliferation and steroidogenesis, providing insights into PCOS pathogenesis.

Quantitative Differences in TGF-β Family Members Measured in Small Antral Follicle Fluids From Women With or Without PCO

CONTEXT

Members of the TGF-β family have been implicated in aberrant follicle development in women with polycystic ovaries (PCO).

OBJECTIVE

Are there quantitative differences in the concentrations of TGF-β family members in fluid from human small antral follicles (hSAFs) in women with or without PCO?

DESIGN AND SETTING

Follicle fluids (FFs) were collected from 4- to 11-mm hSAFs obtained from women undergoing ovarian tissue cryopreservation for fertility preservation.

PATIENTS

FFs from 16 women with PCO (FF = 93) and 33 women without PCO (FF = 92).

MAIN OUTCOME MEASURES

Intrafollicular concentrations of growth differentiation factor-9 (GDF9); anti-Müllerian hormone (AMH); inhibin-A and inhibin-B; total inhibin; activin-A, activin-B, and activin-AB; follistatin; follistatin-like-3; estradiol; and testosterone.

RESULTS

Activin-B concentrations were reported in hSAFs, and concentrations were 10 times higher than activin-A and activin-AB concentrations. Activin-B showed significant associations with other growth factors. Concentrations of inhibin-A and inhibin-B were significantly lower in FFs from women with PCO, especially in hSAFs <8 mm in diameter. AMH concentrations did not differ between the groups in hSAFs <8 mm; however, AMH remained high in hSAFs >8 mm in women with PCO but decreased in women without PCO. Estradiol was significantly lower in FFs from women with PCO and showed significant associations with AMH. Concentrations of GDF9 showed significantly higher concentrations in PCO FFs of follicles >6 mm.

CONCLUSIONS

Altered concentrations of TGF-β family members in hSAFs from women with PCO highlight altered growth factor signaling as a potential mechanism for follicle growth arrest.

Relationships between the antral follicle count, steroidogenesis, and secretion of follicle-stimulating hormone and anti-Müllerian hormone during follicular growth in cattle

BACKGROUND

The antral follicle count (AFC) in mammalian ovaries positively correlates with female fertility. To clarify the causes of differences in fertility between low and high AFC cows, we investigated follicular growth dynamics and hormone concentrations in plasma, follicular fluid, and in vitro growth (IVG) media at different stages of follicular growth.

METHODS

Seven cows were divided into high AFC (n = 4, > 30 follicles) and low AFC (n = 3, < 30 follicles) groups based on the peak AFC detected by ultrasonography. These cows were subjected to estrous synchronization, daily ovarian ultrasonography, and blood collection. Their follicular fluid was collected from dominant follicles at different stages (selection, luteal, and ovulatory phases). In another experiment, we cultured oocyte-cumulus-granulosa cell complexes collected from early antral follicles (< 1 mm) for 12 days. Estradiol-17β (E₂), testosterone (T), progesterone (P₄), and anti-Müllerian hormone (AMH) concentrations in follicular fluids and plasma were measured. Plasma follicle-stimulating hormone (FSH) concentrations were examined. E₂, P₄, and AMH concentrations were also measured in IVG media.

RESULTS

The numbers of small (< 4 mm) and intermediate (4-8 mm) follicles were larger in the high AFC group than in the low AFC group (P < 0.05). The number of intermediate follicles was stable in the low AFC group, indicating consistent development. However, the number of these follicles fluctuated in the high AFC group. Plasma FSH concentrations were higher, whereas E₂ and T concentrations were lower in the low AFC group (P < 0.05). E₂ concentrations and the E₂/P₄ ratio in ovulatory follicles and IVG media on day 8 were higher in the high AFC group (P < 0.05). AMH concentrations in plasma and IVG media (P < 0.01) were higher in the high AFC group.

CONCLUSIONS

The weaker response to FSH of granulosa cells caused low E₂ production in the low AFC group, resulting in high FSH concentrations and the consistent development of intermediate follicles. Conversely, higher E₂ concentrations suppressed FSH secretion in the high AFC group. Granulosa cells in the high AFC group had the ability to produce more AMH than those in the low AFC group throughout IVG culture.

Anti-Müllerian hormone inhibits luteinizing hormone-induced androstenedione synthesis in porcine theca cells

AMH (Anti-Müllerian Hormone) is involved in the regulation of follicle growth initiation and inhibits FSH-induced aromatase expression and estrogen production in granulosa cells. However, the function of AMH in steroidogenesis by theca cells remains unclear. The aim of this study is to investigate the role of AMH as a regulator of the basal and stimulated steroid production by pig granulosa cells (pGCs) and theca cells (pTCs). PGCs and pTCs were incubated with hormones AMH, LH (luteinizing hormone), FSH (follicle stimulating hormone), individually or in combination. The expression of CYP19A1, HSD3B1, CYP11A1, LHCGR, and CYP17A1 mRNA were evaluated by quantitative reverse transcriptase PCR. In pGCs, 10 ng/mL AMH significantly decreased the FSH-stimulated effect on FSHR and CYP19A1 expression and estradiol production. In pTCs, LH treatment significantly increased the expression of HSD3B1, CYP11A1, LHCGR, and androstenedione or progesterone production (P < 0.05). Additionally, 10 ng/mL AMH also significantly decreased the LH-stimulated effects on the expression of HSD3B1, CYP11A1, CYP17A1, LHCGR and androstenedione production. Transfection with siAMHR2-I abolished the suppressive effects of AMH on LH-induced HSD3B1 expression and androstenedione production. Taken together, these results demonstrate that AMH is involved in FSH induced estradiol production in pGCs and LH induced androstenedione production in pTCs by regulating the steroidogenesis pathway.

Functional Genetic Variation in the Anti-Müllerian Hormone Pathway in Women With Polycystic Ovary Syndrome

CONTEXT

Polycystic ovary syndrome (PCOS) is a highly heritable, common endocrine disorder characterized by hyperandrogenism, irregular menses, and polycystic ovaries. PCOS is often accompanied by elevated levels of anti-Müllerian hormone (AMH). AMH inhibits follicle maturation. AMH also inhibits steroidogenesis through transcriptional repression of CYP17A1. We recently identified 16 rare PCOS-specific pathogenic variants in AMH.

OBJECTIVE

To test whether additional members of the AMH signaling pathway also contribute to the etiology of PCOS.

PARTICIPANTS/DESIGN

Targeted resequencing of coding and regulatory regions of AMH and its specific type 2 receptor, AMHR2, was performed on 608 women affected with PCOS and 142 reproductively normal control women. Prediction tools of deleteriousness and in silico evidence of epigenetic modification were used to prioritize variants for functional evaluation. Dual-luciferase reporter assays and splicing assays were used to measure the impact of genetic variants on function.

RESULTS

We identified 20 additional variants in/near AMH and AMHR2 with significantly reduced signaling activity in in vitro assays. Collectively, from our previous study and as reported herein, we have identified a total of 37 variants with impaired activity in/near AMH and AMHR2 in 41 women affected with PCOS, or 6.7% of our PCOS cohort. Furthermore, no functional variants were observed in the 142 phenotyped controls. The functional variants were significantly associated with PCOS in our cohort of 608 women with PCOS and 142 controls (P = 2.3 × 10-5) and very strongly associated with PCOS relative to a larger non-Finnish European (gnomAD) population-based control cohort (P < 1 × 10-9).

CONCLUSION

The AMH signaling cascade plays an important role in PCOS etiology.

Anti-Müllerian Hormone in Fertility Preservation: Clinical and Therapeutic Applications

Anti-Müllerian hormone (AMH) is a member of the transforming growth factor (TGF)-beta family and a key regulator of sexual differentiation and folliculogenesis. While the serum AMH level has been used in reproductive medicine as a biomarker of quantitative ovarian reserve for more than 20 years, new potential therapeutic applications of recombinant AMH are emerging, notably in the field of oncofertility. Indeed, it is well known that chemotherapy, used to treat cancer, induces ovarian follicular depletion and subsequent infertility. Animal models have been used widely to understand the effects of different cytotoxic agents on ovarian function, and several hypotheses regarding chemotherapy gonadotoxicity have been proposed, that is, it might have a direct detrimental effect on the primordial follicles constituting the ovarian reserve and/or on the pool of growing follicles secreting AMH. Recently, a new mechanism of chemotherapy-induced follicular depletion, called the “burn-out effect,” has been proposed. According to this theory, chemotherapeutic agents may lead to a massive growth of dormant follicles which are then destroyed. As AMH is one of the factors regulating the recruitment of primordial follicles from the ovarian reserve, recombinant AMH administration concomitant with chemotherapy might limit follicular depletion, therefore representing a promising option for preserving fertility in women suffering from cancer. This review reports on the potential usefulness of AMH measurement as well as AMH’s role as a therapeutic agent in the field of female fertility preservation.

Clinical application of serum anti-Müllerian hormone in women

Anti-Müllerian hormone (AMH), a peptide growth factor of the transforming growth factor-β family, is a reliable marker of ovarian reserve. Regarding assisted reproductive technology, AMH has been efficiently used as a marker to predict ovarian response to stimulation. The clinical use of AMH has recently been extended and emphasized. The uses of AMH as a predictive marker of menopause onset, diagnostic tool for polycystic ovary syndrome, and assessment of ovarian function before and after gynecologic surgeries or gonadotoxic agents such as chemotherapy have been investigated. Serum AMH levels can also be affected by environmental and genetic factors; thus, the effects of factors that may alter AMH test results should be considered. This review summarizes the findings of recent studies focusing on the clinical application of AMH and factors that influence the AMH level and opinions on the use of the AMH level to assess the probability of conception before reproductive life planning as a “fertility test.”

FSH inhibits AMH to support ovarian estradiol synthesis in infantile mice

Anti-Müllerian hormone (AMH) regulates ovarian function in cyclic females, notably by preventing premature follicle-stimulating hormone (FSH)-mediated follicular growth and steroidogenesis. Its expression in growing follicles is controlled by FSH and by estradiol (E2). In infantile females, there is a transient increase in the activity of the gonadotrope axis, as reflected by elevated levels of both gonadotropins and E2. We previously demonstrated in mice that elevated FSH concentrations are necessary to induce E2 production by preantral/early antral follicles through the stimulation of aromatase expression without supporting their growth. However, whether this action of FSH could involve AMH is unknown. Here, we show that Amh mRNA and protein abundance and serum AMH levels are elevated in infantile mouse females, compared with those in adults. By experimentally manipulating FSH and E2 levels in infantile mice, we demonstrate that high FSH concentrations lower Amh expression specifically in preantral/early antral follicles, whereas E2 has no effect. Importantly, treatment of infantile ovaries in organotypic cultures with AMH decreases FSH-mediated expression of Cyp19a1 aromatase, but it does not alter the expression of cyclin D2-mediating granulosa cell proliferation. Overall, our data indicate that the infantile elevation in FSH levels suppresses Amh expression in preantral/early antral follicles, thereby favoring Cyp19a1 aromatase expression and E2 production. Together with recent discoveries that AMH can act on both the hypothalamus and the pituitary to increase gonadotropin levels, this work suggests that AMH is a critical regulator of the gonadotrope axis during the infantile period, thereby contributing to adult reproductive function programming.

The role of anti-Müllerian hormone in predicting clomiphene citrate resistance in women with polycystic ovarian syndrome

Clomiphene citrate (CC) is the agent of first choice in polycystic ovarian syndrome; however, anovulation problem does not resolve in a quarter of them. Thus, we investigated the value of anti-Müllerian hormone (AMH) in the prediction of ovarian response to CC in women with the polycystic ovarian syndrome (PCOS). This prospective cohort study included 90 anovulatory women with PCOS who were given 50 mg/d CC. The patients who ovulated occupied the group of responders and the patients who did not ovulate in three cycles included in the CC-resistant group. AMH levels of both groups were compared. p < .05 was considered statistically significant. Patients who ovulated had significantly lower serum AMH concentrations compared with the resistant group (p = .001). After analyzing the ROC curve, serum AMH concentration was found to be a useful predictor of CC resistance with the sensitivity of 66% and the specificity of 89%, when the threshold AMH concentration was >12.38 ng/ml in PCOS patients. In the present study, we revealed that the higher the AMH level the poorer the CC response would be in PCOS patients, therefore we recommend measuring the AMH levels of all PCOS patients before planning any ovulation induction treatment to achieve the desired success.