Regulated Expression of ADAMTS Family Members in Follicles and Cumulus Oocyte Complexes: Evidence for Specific and Redundant Patterns During Ovulation1

New insights into the ovulatory process in the human ovary

BACKGROUND

Successful ovulation is essential for natural conception and fertility. Defects in the ovulatory process are associated with various conditions of infertility or subfertility in women. However, our understanding of the intra-ovarian biochemical mechanisms underlying this process in women has lagged compared to our understanding of animal models. This has been largely due to the limited availability of human ovarian samples that can be used to examine changes across the ovulatory period and delineate the underlying cellular/molecular mechanisms in women. Despite this challenge, steady progress has been made to improve our knowledge of the ovulatory process in women by: (i) collecting granulosa cells across the IVF interval, (ii) creating a novel approach to collecting follicular cells and tissues across the periovulatory period from normally cycling women, and (iii) developing unique in vitro models to examine the LH surge or hCG administration-induced ovulatory changes in gene expression, the regulatory mechanisms underlying the ovulatory changes, and the specific functions of the ovulatory factors.

OBJECTIVE AND RATIONALE

The objective of this review is to summarize findings generated using in vivo and in vitro models of human ovulation, with the goal of providing new insights into the mechanisms underlying the ovulatory process in women.

SEARCH METHODS

This review is based on the authors' own studies and a search of the relevant literature on human ovulation to date using PubMed search terms such as 'human ovulation EGF-signaling', 'human ovulation steroidogenesis', 'human ovulation transcription factor', 'human ovulation prostaglandin', 'human ovulation proteinase', 'human ovulation angiogenesis' 'human ovulation chemokine', 'human ovulatory disorder', 'human granulosa cell culture'. Our approach includes comparing the data from the authors' studies with the existing microarray or RNA-seq datasets generated using ovarian cells obtained throughout the ovulatory period from humans, monkeys, and mice.

OUTCOMES

Current findings from studies using in vivo and in vitro models demonstrate that the LH surge or hCG administration increases the expression of ovulatory mediators, including EGF-like factors, steroids, transcription factors, prostaglandins, proteolytic systems, and other autocrine and paracrine factors, similar to those observed in other animal models such as rodents, ruminants, and monkeys. However, the specific ovulatory factors induced, their expression pattern, and their regulatory mechanisms vary among different species. These species-specific differences stress the necessity of utilizing human samples to delineate the mechanisms underlying the ovulatory process in women.

WIDER IMPLICATIONS

The data from human ovulation in vivo and in vitro models have begun to fill the gaps in our understanding of the ovulatory process in women. Further efforts are needed to discover novel ovulatory factors. One approach to address these gaps is to improve existing in vitro models to more closely mimic in vivo ovulatory conditions in humans. This is critically important as the knowledge obtained from these human studies can be translated directly to aid in the diagnosis of ovulation-associated pathological conditions, for the development of more effective treatment to help women with anovulatory infertility or, conversely, to better manage ovulation for contraceptive purposes.

REGISTRATION NUMBER

N/A.

Protease expression in the human and rat cumulus-oocyte complex during the periovulatory period: a role in cumulus-oocyte complex migration†

The migratory and matrix-invading capacities of the cumulus-oocyte complex have been shown to be important for the ovulatory process. In metastatic cancers, these capacities are due to increased expression of proteases, however, there is limited information on protease expression in the cumulus-oocyte complexes. The present study examined cumulus-oocyte complex expression of plasmins, matrix metalloproteases, and A Disintegrin and Metalloproteinase with Thrombospondin Motifs family members in the rat and human. In the rat, human chorionic gonadotropin (hCG) administration increased cumulus-oocyte complex expression of Mmp2, Mmp9, Mmp13, Mmp14, Mmp16, Adamts1, and the protease inhibitors Timp1, Timp3, and Serpine1 by 8-12 h. This ovulatory induction of proteases in vivo could be mimicked by forskolin and ampiregulin treatment of cultured rat cumulus-oocyte complexes with increases observed in Mmp2, Mmp13, Mmp14, Mmp16, Mmp19, Plat, and the protease inhibitors Timp1, Timp3, and Serpine1. Comparison of expression between rat cumulus-oocyte complexes and granulosa cells at the time of ovulation showed decreased Mmp9 and increased Mmp13, Mmp14, Mmp16, Adamts1, Timp1, and Timp3 expression in the cumulus-oocyte complexes. In human, comparison of expression between cumulus and granulosa cells at the time of in vitro fertilization retrieval showed decreased MMP1, MMP2, MMP9, and ADAMTS1, while expression of MMP16, TIMP1, and TIMP3 were increased. Treatment of expanding rat cumulus-oocyte complexes with a broad spectrum matrix metalloproteases inhibitor, GM6001, significantly reduced the migration of cumulus cells in vitro. These data provide evidence that multiple proteases and their inhibitors are expressed in the cumulus-oocyte complex and play an important role in imparting the migratory phenotype of the cumulus-oocyte complex at the time of ovulation. Summary Sentence  Multiple proteases and their inhibitors are induced in the cumulus-oocyte complex (COC) during the periovulatory period and potentially play an important role in imparting the migratory phenotype of the COC at the time of ovulation.

A delayed ovulation of progestin-primed ovarian stimulation (PPOS) by downregulating the LHCGR/PGR pathway

Progestin-primed ovarian stimulation (PPOS) is a new ovulation stimulation protocol, and its role in ovulation and regulatory mechanism is unclear. The clinical PPOS protocol was simulated in mice. The ovulated oocytes, estradiol, progesterone, and luteinizing hormone (LH) levels were analyzed at different hours after trigger. mRNA extraction and real-time PCR, hematoxylin and eosin staining, and immunofluorescence of ovaries were used to explore the involved signaling pathways. The PPOS group had a delayed ovulation at 12.5 h after trigger. Its suppressed LH level reduced the expression of luteinizing hormone/choriogonadotropin receptor (LHCGR) on the preovulatory follicles before trigger and significantly decreased the following progesterone synthesis, blood progesterone level, and progesterone receptor (PGR) expression within 4-6 h after trigger. Furthermore, the important ovulatory genes regulated by PGR including ADAMTS-1, VEGF-A, and EDN2 were downregulated, ultimately delaying the ovulation. PPOS suppresses the LH level before trigger and decreases the synthesis of progesterone after trigger, thus delaying the ovulation by downregulating the LHCGR-PGR pathway.

ADAMTS Proteases: Importance in Animal Reproduction

Many reproductive physiological processes, such as folliculogenesis, ovulation, implantation, and fertilization, require the synthesis, remodeling, and degradation of the extracellular matrix (ECM). The ADAMTS (A Disintegrin and Metalloproteinase with Thrombospondin Motifs) family genes code for key metalloproteinases in the remodeling process of different ECM. Several genes of this family encode for proteins with important functions in reproductive processes; in particular, ADAMTS1, 4, 5 and 9 are genes that are differentially expressed in cell types and the physiological stages of reproductive tissues. ADAMTS enzymes degrade proteoglycans in the ECM of the follicles so that the oocytes can be released and regulate follicle development during folliculogenesis, favoring the action of essential growth factors, such as FGF-2, FGF-7 and GDF-9. The transcriptional regulation of ADAMTS1 and 9 in preovulatory follicles occurs because of the gonadotropin surge in preovulatory follicles, via the progesterone/progesterone receptor complex. In addition, in the case of ADAMTS1, pathways involving protein kinase A (PKA), extracellular signal regulated protein kinase (ERK1/2) and the epidermal growth factor receptor (EGFR) might contribute to ECM regulation. Different Omic studies indicate the importance of genes of the ADAMTS family from a reproductive aspect. ADAMTS genes could serve as biomarkers for genetic improvement and contribute to enhance fertility and animal reproduction; however, more research related to these genes, the synthesis of proteins encoded by these genes, and regulation in farm animals is needed.

Metzincin metalloproteases in PGC migration and gonadal sex conversion

Development of a functional gonad includes migration of primordial germ cells (PGCs), differentiations of somatic and germ cells, formation of primary follicles or spermatogenic cysts with somatic gonadal cells, development and maturation of gametes, and subsequent releasing of mature germ cells. These processes require extensive cellular and tissue remodeling, as well as broad alterations of the surrounding extracellular matrix (ECM). Metalloproteases, including MMPs (matrix metalloproteases), ADAMs (a disintegrin and metalloproteinases), and ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs), are suggested to have critical roles in the remodeling of the ECM during gonad development. However, few research articles and reviews are available on the functions and mechanisms of metalloproteases in remodeling gonadal ECM, gonadal development, or gonadal differentiation. Moreover, most studies focused on the roles of transcription and growth factors in early gonad development and primary sex determination, leaving a significant knowledge gap on how differentially expressed metalloproteases exert effects on the ECM, cell migration, development, and survival of germ cells during the development and differentiation of ovaries or testes. We will review gonad development with focus on the evidence of metalloprotease involvements, and with an emphasis on zebrafish as a model for studying gonadal sex differentiation and metalloprotease functions.

Association of ADAMTS proteoglycanases downregulation with IVF-ET outcomes in patients with polycystic ovary syndrome: a systematic review and meta-analysis

BACKGROUND

A disintegrin and metalloproteinase with thrombospondin-like motifs (ADAMTS) is involved in inflammation and fertility in women with polycystic ovary syndrome (PCOS). This study aims to assess the role of ADAMTS level in the outcomes of in vitro fertilization and embryo transfer (IVF-ET) in women with PCOS, using a meta-analytic approach.

METHODS

We systematically searched Web of Science, PubMed, EmBase, and the Cochrane library to identify potentially eligible studies from inception until December 2021. Study assess the role of ADAMTS levels in patients with PCOS was eligible in this study. The pooled effect estimates for the association between ADAMTS level and IVF-ET outcomes were calculated using the random-effects model.

RESULTS

Five studies involving a total of 181 patients, were selected for final analysis. We noted that ADAMTS-1 levels were positively correlated to oocyte maturity (r = 0.67; P = 0.004), oocyte recovery (r = 0.74; P = 0.006), and fertilization (r = 0.46; P = 0.041) rates. Moreover, ADAMTS-4 levels were positively correlated to oocyte recovery (r = 0.91; P = 0.001), and fertilization (r = 0.85; P = 0.017) rates. Furthermore, downregulation of ADAMTS-1, ADAMTS-4, ADAMTS-5, and ADAMTS-9 was associated with elevated follicle puncture (ADAMTS-1: weighted mean difference [WMD], 7.24, P < 0.001; ADAMTS-4: WMD, 7.20, P < 0.001; ADAMTS-5: WMD, 7.20, P < 0.001; ADAMTS-9: WMD, 6.38, P < 0.001), oocytes retrieval (ADAMTS-1: WMD, 1.61, P < 0.001; ADAMTS-4: WMD, 3.63, P = 0.004; ADAMTS-5: WMD, 3.63, P = 0.004; ADAMTS-9: WMD, 3.20, P = 0.006), and Germinal vesicle oocytes levels (ADAMTS-1: WMD, 2.89, P < 0.001; ADAMTS-4: WMD, 2.19, P < 0.001; ADAMTS-5: WMD, 2.19, P < 0.001; ADAMTS-9: WMD, 2.89, P < 0.001). Finally, the oocytes recovery rate, oocyte maturity rate, fertilization rate, cleavage rate, good-quality embryos rate, blastocyst formation rate, and clinical pregnancy rate were not affected by the downregulation of ADAMTS-1, ADAMTS-4, ADAMTS-5, and ADAMTS-9 (P > 0.05).

CONCLUSIONS

This study found that the outcomes of IVF-EF in patients with PCOS could be affected by ADAMTS-1 and ADAMTS-4; further large-scale prospective studies should be performed to verify these results.

Transcriptomic analyses of the HPG axis-related tissues reveals potential candidate genes and regulatory pathways associated with egg production in ducks

BACKGROUND

Egg production is one of the most important economic traits in the poultry industry. The hypothalamic-pituitary-gonadal (HPG) axis plays an essential role in regulating reproductive activities. However, the key genes and regulatory pathways within the HPG axis dominating egg production performance remain largely unknown in ducks.

RESULTS

In this study, we compared the transcriptomic profiles of the HPG-related tissues between ducks with high egg production (HEP) and low egg production (LEP) to reveal candidate genes and regulatory pathways dominating egg production. We identified 543, 759, 670, and 181 differentially expressed genes (DEGs) in the hypothalamus, pituitary, ovary stroma, and F5 follicle membrane, respectively. Gene Ontology (GO) analysis revealed that DEGs from four HPG axis-related tissues were enriched in the "cellular component" category. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that the neuroactive ligand-receptor interaction pathway was significantly enriched based on DEGs commonly identified in all four HPG axis-related tissues. Gene expression profiles and Protein-Protein Interaction (PPI) network were performed to show the regulatory relationships of the DEGs identified. Five DEGs encoding secreted proteins in the hypothalamus and pituitary have interaction with DEGs encoding targeted proteins in the ovary stroma and F5 follicle membrane, implying that they were these DEGs might play similar roles in the regulation of egg production.

CONCLUSIONS

Our results revealed that neuroactive ligand-receptor interaction pathway and five key genes(VEGFC, SPARC, BMP2, THBS1, and ADAMTS15) were identified as the key signaling pathways and candidate genes within the HPG axis responsible for different egg production performance between HEP and LEP. This is the first study comparing the transcriptomic profiles of all HPG axis-related tissues in HEP and LEP using RNA-seq in ducks to the best of our knowledge. These data are helpful to enrich our understanding of the classical HPG axis regulating the egg production performance and identify candidate genes that can be used for genetic selection in ducks.

Metalloproteases in gonad formation and ovulation

Changes in expression or activation of various metalloproteases including matrix metalloproteases (Mmp), a disintegrin and metalloprotease (Adam) and a disintegrin and metalloprotease with thrombospondin motif (Adamts), and their endogenous inhibitors (tissue inhibitors of metalloproteases, Timp), have been shown to be critical for ovulation in various species from studies in past decades. Some of these metalloproteases such as Adamts1, Adamts9, Mmp2, and Mmp9 have also been shown to be regulated by luteinizing hormone (LH) and/or progestin, which are essential triggers for ovulation in all vertebrate species. Most of these metalloproteases also express broadly in various tissues and cells including germ cells and somatic gonad cells. Thus, metalloproteases likely play roles in gonad formation processes comprising primordial germ cell (PGC) migration, development of germ and somatic cells, and sex determination. However, our knowledge on the functions and mechanisms of metalloproteases in these processes in vertebrates is still lacking. This review will summarize our current knowledge on the metalloproteases in ovulation and gonad formation with emphasis on PGC migration and germ cell development.

Induction of right open reading frame kinase 3 (RIOK3) during ovulation and luteinisation in rat ovary

Atypical protein serine kinase RIOK3 is involved in cellular invasion and survival. The spatiotemporal expression pattern and regulatory mechanisms controlling expression of Riok3 were investigated in the rat ovary during the periovulatory period. Immature female rats (22-23 days old) were treated with pregnant mare's serum gonadotropin (PMSG) to stimulate follicular development, followed 48h later by injection with human chorionic gonadotrophin (hCG). Ovaries, granulosa cells, or theca-interstitial cells were collected at various times after hCG administration. Both real-time polymerase chain reaction (PCR) and in situ hybridisation analysis revealed that Riok3 was highly induced in both granulosa cells and theca-interstitial cells by hCG. Riok3 expression was induced in theca-interstitial cells at 4h after hCG. However, the expression of Riok3 mRNA was stimulated in granulosa cells at 8h. Both protein kinase C inhibitor (GF109203) and the protein kinase A inhibitor (H89) could block the stimulation of Riok3 mRNA by hCG. Furthermore, Riok3 induction is dependent on new protein synthesis. Inhibition of prostaglandin synthesis or progesterone action did not alter Riok3 mRNA expression, whereas inhibition of the epidermal growth factor (EGF) pathway downregulated Riok3 expression. In conclusion, our findings suggest that the induction of the RIOK3 may be important for ovulation and luteinisation.

To Compare the Effect of GnRH Agonist versus Human Chorionic Gonadotropin (HCG) Trigger on Clinical Pregnancy Rate in Intrauterine Insemination Cycle

Context:

Gonadotropin-releasing hormone (GnRH) agonist trigger mimics the natural surge more closely with both luteinizing hormone (LH) and follicle-stimulating hormone surge. The present study attempts to find whether this apparent physiological advantage translates into the better pregnancy rate.

Aims:

To compare the effect of GnRH agonist versus human chorionic gonadotropin (hCG) trigger on the clinical pregnancy rate (CPR) in infertile women undergoing intrauterine insemination (IUI) with oral ovulogens.

Settings and Design:

Retrospective analysis at a tertiary care in vitro fertilization center.

Materials and Methods:

The records of 280 infertile women, who underwent IUI with oral ovulogens were analyzed. Women who received 0.2 mg triptorelin (GnRH agonist (GnRHa)) as trigger were categorised in Group A (n = 129) and those who received 10,000 IU urinary hCG in Group B (n = 151). The outcome in terms of CPR was studied.

Statistical Analysis Used:

The quantitative variables were compared using the independent t-test/Mann–Whitney test. The qualitative variables were compared using the Chi-square test. P < 0.05 was considered statistically significant.

Results:

There was a trend toward better CPR in Group A (21/129 – 16.28%) than in Group B (16/151 – 10.60%), although the difference was not found to be statistically significant (P – 0.162).

Conclusions:

There was a trend toward better CPR with the use of GnRH agonist trigger in IUI cycles with oral ovulogens in comparison to hCG trigger, although the difference was not found to be statistically significant. Further randomized controlled trials are needed to confirm these findings.

ADAMTS proteoglycanases downregulation with impaired oocyte quality in PCOS

OBJECTIVE

A disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS-4) and ADAMTS-5 normal expression levels are essential for ovulation and subsequent fertilization. The objective of the present study was to assess expression pattern of these genes in cumulus cells (CCs) taken from patients with polycystic ovary syndrome (PCOS) and to investigate any possible relationship with the oocyte quality.

METHODS

ADAMTS-4 and -5 expression levels within CCs containing oocytes at the metaphase II (MII) and germinal vesicle (GV) stages, taken from 35 patients with PCOS and 35 women with normal ovarian function, were investigated using RT-qPCR. Moreover, possible correlations between ADAMTS-4, ADAMTS-5, and progesterone receptors (PRs) expression as well as oocyte quality were evaluated.

RESULTS

ADAMTS-4 and -5 expression levels were dramatically diminished in the CCs of the PCOS patients when compared to the controls. ADAMTS-4 and -5 expression levels were correlated with each other and with the oocyte quality. Furthermore, lower expression levels of ADAMTS-4 and -5 in the PCOS patients were strongly correlated with the diminished PRs expression levels.

CONCLUSION

Downregulation of ADAMTS-4 and -5 in the human CCs of the PCOS patients correlated with the decline in the PRs expression, and impaired oocyte quality may cause lower oocyte recovery, maturation, and fertilization rate.

Morphology and Biochemistry of Ovulation

The process of ovulation involves multiple and iterrelated genetic, biochemical, and morphological events: cessation of the proliferation of granulosa cells, resumption of oocyte meiosis, expansion of cumulus cell-oocyte complexes, digestion of the follicle wall, and extrusion of the metaphase-II oocyte. The present narrative review examines these interrelated steps in detail. The combined or isolated roles of the follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are highlighted. Genes indiced by the FSH genes are relevant in the cumulus expansion, and LH-induced genes are critical for the resumption of meiosis and digestion of the follicle wall. A non-human model for follicle-wall digestion and oocyte release was provided.

Androgens regulate ovarian gene expression by balancing Ezh2-Jmjd3 mediated H3K27me3 dynamics

Conventionally viewed as male hormone, androgens play a critical role in female fertility. Although androgen receptors (AR) are transcription factors, to date very few direct transcriptional targets of ARs have been identified in the ovary. Using mouse models, this study provides three critical insights about androgen-induced gene regulation in the ovary and its impact on female fertility. First, RNA-sequencing reveals a number of genes and biological processes that were previously not known to be directly regulated by androgens in the ovary. Second, androgens can also influence gene expression by decreasing the tri-methyl mark on lysine 27 of histone3 (H3K27me3), a gene silencing epigenetic mark. ChIP-seq analyses highlight that androgen-induced modulation of H3K27me3 mark within gene bodies, promoters or distal enhancers have a much broader impact on ovarian function than the direct genomic effects of androgens. Third, androgen-induced decrease of H3K27me3 is mediated through (a) inhibiting the expression and activity of Enhancer of Zeste Homologue 2 (EZH2), a histone methyltransferase that promotes tri-methylation of K27 and (b) by inducing the expression of a histone demethylase called Jumonji domain containing protein-3 (JMJD3/KDM6B), responsible for removing the H3K27me3 mark. Androgens through the PI3K/Akt pathway, in a transcription-independent fashion, increase hypoxia-inducible factor 1 alpha (HIF1α) protein levels, which in turn induce JMJD3 expression. Furthermore, proof of concept studies involving in vivo knockdown of Ar in the ovary and ovarian (granulosa) cell-specific Ar knockout mouse model show that ARs regulate the expression of key ovarian genes through modulation of H3K27me3.

Identification of Circular RNAs in Hypothalamus of Gilts during the Onset of Puberty

The disorders of puberty have shown negative outcomes on health of mammals, and the hypothalamus is thought to be the main regulator of puberty by releasing GnRH. Many studies show that the circular RNAs (circRNAs) might be implicated in the timing of puberty in mammals. However, the circRNAs in the hypothalamus of gilts have not been explored. To profile the changes and biological functions of circRNAs in the hypothalamus during the onset of puberty, RNA-seq was utilized to establish pre-, in-, and post-pubertal hypothalamic circRNAs profiles. In this study, the functions of hypothalamic circRNAs were enriched in the signaling pathway of neurotrophin, progesterone-mediated oocyte maturation, oocyte meiosis, insulin, ErbB, and mTOR, which have been highly suggested to be involved in the timing of puberty. Furthermore, 53 circRNAs were identified to be putative hypothalamus-specific expressed circRNAs, and some of them were exclusively expressed in the one of three pubertal stages. Moreover, 22 differentially expressed circRNAs were identified and chosen to construct the circRNA-miRNA-gene network. Moreover, 10 circRNAs were found to be driven by six puberty-related genes (ESR1, NF1, APP, ENPP2, ARNT, and DICER1). Subsequently, the expression changes of several circRNAs were confirmed by RT-qPCR. Collectively, the preliminary results of hypothalamic circRNAs provided useful information for the investigation of the molecular mechanism for the timing of puberty in gilts.

Nuclear receptors: Key regulators of somatic cell functions in the ovulatory process

The development of the ovarian follicle to its culmination by ovulation is an essential element of fertility. The final stages of ovarian follicular growth are characterized by granulosa cell proliferation and differentiation, and steroid synthesis under the influence of follicle-stimulating hormone (FSH). The result is a population of granulosa cells poised to respond to the ovulatory surge of luteinizing hormone (LH). Members of the nuclear receptor superfamily of transcription factors play indispensable roles in the regulation of these events. The key regulators of the final stages of follicular growth that precede ovulation from this family include the estrogen receptor beta (ESR2) and the androgen receptor (AR), with additional roles for others, including steroidogenic factor-1 (SF-1) and liver receptor homolog-1 (LRH-1). Following the LH surge, the mural and cumulus granulosa cells undergo rapid changes that result in expansion of the cumulus layer, and a shift in ovarian steroid hormone biosynthesis from estradiol to progesterone production. The nuclear receptor best associated with these events is LRH-1. Inadequate cumulus expansion is also observed in the absence of AR and ESR2, but not the progesterone receptor (PGR). The terminal stages of ovulation are regulated by PGR, which increases the abundance of the proteases that are directly responsible for rupture. It further regulates the prostaglandins and cytokines associated with the inflammatory-like characteristics of ovulation. LRH-1 regulates PGR, and is also a key regulator of steroidogenesis, cellular proliferation, and cellular migration, and cytoskeletal remodeling. In summary, nuclear receptors are among the panoply of transcriptional regulators with roles in ovulation, and several are necessary for normal ovarian function.

Core Binding Factors are essential for ovulation, luteinization, and female fertility in mice

Core Binding Factors (CBFs) are a small group of heterodimeric transcription factor complexes composed of DNA binding proteins, RUNXs, and a non-DNA binding protein, CBFB. The LH surge increases the expression of Runx1 and Runx2 in ovulatory follicles, while Cbfb is constitutively expressed. To investigate the physiological significance of CBFs, we generated a conditional mutant mouse model in which granulosa cell expression of Runx2 and Cbfb was deleted by the Esr2Cre. Female Cbfbflox/flox;Esr2cre/+;Runx2flox/flox mice were infertile; follicles developed to the preovulatory follicle stage but failed to ovulate. RNA-seq analysis of mutant mouse ovaries collected at 11 h post-hCG unveiled numerous CBFs-downstream genes that are associated with inflammation, matrix remodeling, wnt signaling, and steroid metabolism. Mutant mice also failed to develop corpora lutea, as evident by the lack of luteal marker gene expression, marked reduction of vascularization, and excessive apoptotic staining in unruptured poorly luteinized follicles, consistent with dramatic reduction of progesterone by 24 h after hCG administration. The present study provides in vivo evidence that CBFs act as essential transcriptional regulators of both ovulation and luteinization by regulating the expression of key genes that are involved in inflammation, matrix remodeling, cell differentiation, vascularization, and steroid metabolisms in mice.

Versican expression level in cumulus cells is associated with human oocyte developmental competence

To study the relationship between the expression of 10 selected genes in cumulus cells and the corresponding oocyte development competence, and the effect of patient age and body mass index on gene expression of cumulus cells, we collected 354 cumulus cell masses associated with individual oocyte from 48 women. The expression levels of the genes involved in glucose metabolism (PFKP, PKM2, LDHA and GFPT) and expansion (HAS2, VCAN, TNFAIP6, PTGS2, PTX3 and SDC4) in cumulus cells were detected by reverse transcription polymerase chain reaction. These were compared among oocyte maturity, fertilization, embryo morphology and implantation, and analyzed the effect of the subject's age and body mass index. Cumulus cell PFKP expression from mature oocytes was higher than those from immature oocytes (P = 0.014), and VCAN expression was higher from oocytes that developed into high-quality embryos (P = 0.024). TNFAIP6 expression in cumulus cells from fertilized oocytes was lower than that from unfertilized oocytes (P = 0.044). The levels of VCAN, TNFAIP6, PTX3 and SDC4 were changed significantly as a function of the subject's age and body mass index. In conclusion, the level of VCAN expression in cumulus cells is positively correlated with the early embryo morphology score, and with further development could perhaps be used to evaluate oocyte developmental competence to complement embryonic morphological assessment.

ABBREVIATIONS

CCs: cumulus cells; GDF9: growth differentiation factor 9; BMP15: bone morphogenetic protein 15; PTGS2: prostaglandin synthase 2; HAS2: hyaluronic acid synthase 2; VCAN: versican; GREM1: gremlin 1; PFKP: phosphofructokinase, platelet; PKM2: pyruvate kinase isozyme type M2; LDHA: lactic dehydrogenase; GFPT: glucosaminefructo-6-phosphate transaminase; TNFAIP6: tumor necrosis factor 6 protein; PTX3: penetrin 3; SDC4: syndecan-4; BMI: body mass index; MD: median values; IQR: interquartile range; FSH: follicle-stimulating hormone; LH: luteinizing hormone; HCG: human chorionic gonadotropin; ICSI: intracytoplasmic sperm injection; GnRH: gonadotropin-releasing hormone; hMG: human menopausal gonadotropin; GV: germinal vesicle; M I: metaphase I; M II: metaphase II; cDNA: complementary DNA; SD: standard deviation.

ADAMTS1 and HSPG2 mRNA levels in cumulus cells are related to human oocyte quality and controlled ovarian hyperstimulation outcomes

PURPOSE

The study investigated potential correlations between the expression levels of ADAMTS1 and HSPG2 in cumulus cells (CCs) and controlled ovarian hyperstimulation (COH) outcomes.

METHODS

RT-PCR was used to determine ADAMTS1 and HSPG2 mRNA levels in mice CCs at different timepoints (0, 4, 8, 12, and 16 h) after human chorionic gonadotropin (hCG) injection, and in CCs after RNAi treatment. Women with polycystic ovary syndrome (PCOS) (n = 45) and normal ovulatory controls (n = 103) undergoing IVF/ICSI were recruited. Relative ADAMTS1 and HSPG2 mRNA levels were measured by RT-PCR. Moreover, correlations of ADAMTS1 and HSPG2 levels with COH outcomes were analyzed.

RESULTS

At different timepoints after hCG treatment, ADAMTS1 mRNA had the highest level at 12 h, whereas HSPG2 showed opposite profiles to ADAMTS1 with the lowest level at 12 h. HSPG2 expression was upregulated after ADAMTS1 RNAi treatment The PCOS group had higher HSPG2 and lower ADAMTS1 expression levels than controls. In normal ovulatory women (control group), a higher expression of ADAMTS1 and lower expression of HSPG2 were associated with more mature oocytes, transplantable embryos, and good quality embryos, whereas higher transplantable embryo rates and good quality embryo rates were obtained only with lower HSPG2 expression. ROC curves showed the co-measurement of ADAMTS1 and HSPG2 had a better predictive power than separate analyses.

CONCLUSION

The dynamic profiles of ADAMTS1 and HSPG2 were inversely correlated in CCs. In PCOS and normal ovulatory patients, higher ADAMTS1 and lower HSPG2 expression levels in CCs were related to better COH outcomes.

Matrix-degrading protease ADAMTS-5 cleaves inter-α-inhibitor and releases active heavy chain 2 in synovial fluids from arthritic patients

Destruction of the cartilage matrix in joints is an important feature of arthritis. Proteolytic degradation of cartilage glycoproteins can contribute to the loss of matrix integrity. Human inter-α-inhibitor (IαI), which stabilizes the extracellular matrix, is composed of the light-chain serine proteinase inhibitor bikunin and two homologous heavy chains (HC1 and HC2) covalently linked through chondroitin 4-sulfate. Inflammation promotes the transfer of HCs from chondroitin 4-sulfate to hyaluronan by tumor necrosis factor-stimulated gene-6 protein (TSG-6). This reaction generates a covalent complex between the heavy chains and hyaluronan that can promote leukocyte invasion. This study demonstrates that both IαI and the HC-hyaluronan complex are substrates for the extracellular matrix proteases ADAMTS-5 and matrix metalloprotease (MMP) -3, -7, and -13. The major cleavage sites for all four proteases are found in the C terminus of HC2. ADAMTS-5 and MMP-7 displayed the highest activity toward HC2. ADAMTS-5 degradation products were identified in mass spectrometric analysis of 29 of 33 arthropathic patients, indicating that ADAMTS-5 cleavage occurs in synovial fluid in arthritis. After cleavage, free HC2, together with TSG-6, is able to catalyze the transfer of heavy chains to hyaluronan. The release of extracellular matrix bound HC2 is likely to increase the mobility of the HC2/TSG-6 catalytic unit and consequently increase the rate of the HC transfer reaction. Ultimately, ADAMTS-5 cleavage of HC2 could alter the physiological and mechanical properties of the extracellular matrix and contribute to the progression of arthritis.

MicroRNA-375 regulates oocyte in vitro maturation by targeting ADAMTS1 and PGR in bovine cumulus cells

MicroRNAs (miRNAs) have attracted increasing attention for their function in oocyte in vitro maturation (IVM). In this study, we aimed to explore the functional role and underlying mechanism of miR-375 in oocyte IVM. Cumulus-oocyte complexes (COCs) were cultured in standard cell culture conditions until they reach metaphase II (MII) stage. MiR-375 overexpression or knockdown was achieved by corresponding lentiviral transduction. Levels of miR-375, disintegrin and metalloproteinase with thrombospondin-like motifs 1 (ADAMTS1) mRNA and progesterone receptor (PGR) mRNA were detected by qRT-PCR. Western blotting was used to assess the expression of ADAMTS1 and PGR protein. The targeted interaction between miR-375 and ADAMTS1 or PGR was verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. Our results demonstrate that miR-375 is downregulated, and ADAMTS1 and PGR are upregulated in cumulus cells during COC maturation. MiR-375 negatively regulates COC maturation. Moreover, ADAMTS1 and PGR are two targets of miR-375 in cumulus cells. ADAMTS1 or PGR knockdown represses COC maturation and miR-375 inhibits the expression levels of ADAMTS1 and PGR in cumulus cells. Additionally, miR-375 overexpression-mediated suppressive effect on COC maturation is abated by ADAMTS1 or PGR expression restoration. In conclusion, our study suggests that miR-375 represses oocyte IVM at least partially through targeting ADAMTS1 and PGR in cumulus cells, providing a novel insight for the involvement and underlying mechanism of miR-375 in oocyte IVM.

Hypoxia Limits the Growth of Bovine Follicles in Vitro by Inhibiting Estrogen Receptor α

Simple Summary

It is well documented that a hypoxic environment at high altitudes decreased the fertility of female domestic animals because of embryonic or fetal losses, intrauterine growth restriction, and birth weight reduction. However, little study has been performed on for the effects of hypoxia on bovine ovary function. In this study, we found that the hypoxia plays an important role in regulating follicular survival and genes expression. Hypoxia limits the growth of bovine follicles cultured in vitro through inhibition of ERα, which could provide useful information for future studies relating to reproduction of cattle.

Abstract

Female animals living in the Qinghai-Tibet Plateau have lower ovulation rates because of the hypoxic environment, however, the mechanism of hypoxia on animal follicles is unclear. In this study, the effects of hypoxia on bovine follicles were investigated using an in vitro follicular culture system. The results show that there was a significant decrease in follicular diameter from day 3 to day 6 in both hypoxia and hypoxia with estrogen (E₂) and fulvestrant (ICI 182780) (hypoxia + E₂ + ICI) groups, when compared with a normoxia group (p < 0.05). We also observed significant downregulation of ERα and FSHR, while upregulation of LHCGR expression in the hypoxia group and hypoxia + E₂ + ICI groups compared to the normoxia group (p < 0.05). The expression of IGF1 gene was significantly downregulated in hypoxia + E₂ + ICI group when compared to the hypoxia + E₂ group (p < 0.05). The expression of HIF1A, ADAMTS1, VEGFA, and EDN2 were upregulated in both hypoxia and hypoxia + E₂ + ICI groups in comparison to normoxia group (p < 0.05). Under hypoxic conditions, the addition of E₂ resulted in a decrease of HIF1A protein but an increase of ERα protein in cultured bovine follicles (p < 0.05). In summary, hypoxia limits the growth of bovine follicle cultured in vitro through inhibition of ERα.

Expression and regulation of high mobility group AT-hook 1 (HMGA1) during ovulation and luteinisation in rat ovary

High mobility group AT-hook 1 (HMGA1) is able to regulate gene expression and function as a tumour suppressor. The spatiotemporal expression pattern of HMGA1 was investigated in this study. Immature female rats (22–23 days old) were treated with 10IU, s.c., pregnant mare’s serum gonadotrophin to stimulate follicular development, followed 48h later by injection with 5IU, s.c., human chorionic gonadotrophin (hCG). Whole ovaries or granulosa cells were collected at various times after hCG administration (n=3 per time point). Real-time polymerase chain reaction and western blot analysis revealed that HMGA1 was highly stimulated in the ovary by 4–12h after hCG treatment. In situ hybridisation analysis demonstrated that Hmga1 mRNA expression was induced in granulosa cells between 8 and 12h after hCG treatment. There was negligible Hmga1 mRNA signal observed in newly forming corpora lutea. In addition, the data indicated that both the protein kinase (PK) A and PKC pathways regulated Hmga1 expression in rat granulosa cells. In rat granulosa cell cultures, upregulation of Hmga1 was dependent on new protein synthesis because Hmga1 was inhibited by cycloheximide. Furthermore, Hmga1 mRNA expression in rat granulosa cell cultures was inhibited by AG1478, whereas NS398 and RU486 had no effect, suggesting that Hmga1 expression was regulated, in part, by the epidermal growth factor pathway. In summary, the findings of this study suggest that induction of Hmga1 may be important for theca and granulosa cell differentiation into luteal cells.

The role of ADAMTS4 and ADAMTS9 in cardiovascular disease in premature ovarian insufficiency and idiopathic hypogonadotropic hypogonadism

PURPOSE

We aimed to determine the relation of a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS4), and a disintegrin and metalloproteinase with thrombospondin motifs-9 (ADAMTS9) with cardiovascular disease (CVD) risk, in ovarian dysfunction patients with premature ovarian insufficiency (POI), and idiopathic hypogonadotropic hypogonadism (IHH).

METHODS

43 IHH and 44 POI patients were enrolled to this case-control study. Serum hormonal parameters, lipid profiles, ADAMTS4 and ADAMTS9 levels were measured. Lipid accumulation product (LAP) index, visceral adiposity index (VAI), and homeostasis model assessment of insulin resistance (HOMA-IR) were calculated. The patients with at least two out of the four following criteria were accepted to have increased CVD risk; waist-to-hip ratio (WHR) ≥ 0.8, waist circumference (WC) ≥ 79 cm, triglycerides (TG) ≥ 150 mg/dL, high-density lipoprotein cholesterol (HDL-C) < 50 mg/dL. Serum ADAMTS4 and ADAMTS9 levels were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

ADAMTS4 and ADAMTS9 levels were significantly higher in the IHH group than the POI group (p = 0.002, and p = 0.013, respectively). IHH group had significantly higher levels of insulin, HOMA-IR index, and LAP index (p = 0.006, p = 0.005, and p = 0.013, respectively). The mean age of patients in the IHH group (23.60 ± 5.64 years) was significantly lower than the POI group (31.05 ± 6.03 years), (p < 0.001). Odds ratios (OR) were 1.236 (95% CI 1.055-1.447) and 1.002 (95% CI 1.000-1.004) for LAP index and ADAMTS4, respectively, in the IHH group. These two parameters found to have high predictivity for CVD risk in the IHH group (p = 0.009 and p = 0.028, respectively).

CONCLUSION

The lower levels of ADAMTS4 in the POI group, when compared with the IHH patients pointed out that even limited hormone secretion and ovulation in the POI group, may have protective effect on cardiovascular system. The higher levels of ADAMTS4 and LAP index in the IHH group demonstrated the increased risk of these patients for CVD.

Molecular organization and mechanical properties of the hyaluronan matrix surrounding the mammalian oocyte

Successful ovulation and oocyte fertilization are essential prerequisites for the beginning of life in sexually reproducing animals. In mammalian fertilization, the relevance of the protein coat surrounding the oocyte plasma membrane, known as zona pellucida, has been widely recognized, while, until not too long ago, the general belief was that the cumulus oophorus, consisting of follicle cells embedded in a hyaluronan rich extracellular matrix, was not essential. This opinion was based on in vitro fertilization procedures, in which a large number of sperms are normally utilized and the oocyte can be fertilized even if depleted of cumulus cells. Conversely, in vivo, only very few sperm cells reach the fertilization site, arguing against the possibility of a coincidental encounter with the oocyte. In the last two decades, proteins required for HA organization in the cumulus extracellular matrix have been identified and the study of fertility in mice deprived of the corresponding genes have provided compelling evidence that this jelly-like coat is critical for fertilization. This review focuses on the advances in understanding the molecular interactions making the cumulus environment suitable for oocyte and sperm encounter. Most of the studies on the molecular characterization of the cumulus extracellular matrix have been performed in the mouse and we will refer essentially to findings obtained in this animal model.

Expression of ADAMTS13 in Normal and Abnormal Placentae and Its Potential Role in Angiogenesis and Placenta Development

OBJECTIVE

ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 repeats, member 13) is primarily synthesized in liver. The biosynthesis of ADAMTS13 and its physiological role in placenta are not known.

APPROACH AND RESULTS

We used real-time polymerase chain reaction, immunohistochemistry, and Western blotting analyses, as well as proteolytic cleavage of FRETS (fluorescent resonance energy transfers)-VWF73, to determine ADAMTS13 expression in placenta and trophoblasts obtained from individuals with normal pregnancy and patients with severe preeclampsia. We also determined the role of ADAMTS13 in extravillous trophoblasts using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, wound scratch assay, transwell migration assay, tube formation assay, and tissue outgrowth assays. We showed that full-length and proteolytically active ADAMTS13 was expressed in normal human placenta, primarily in the trophoblasts and villous core fetal vessel endothelium during pregnancy. Placental expression of ADAMTS13 mRNA, protein, and proteolytic activity was at the highest levels during the first trimester and significantly reduced at the term of gestation. Additionally, significantly reduced levels of placental ADAMTS13 expression was detected under hypoxic conditions and in patients with preeclampsia. In addition, recombinant ADAMTS13 protease stimulated proliferation, migration, invasion, and network formation of trophoblastic cells in culture. Finally, knockdown of ADAMTS13 expression attenuated the ability of tube formation in trophoblast (HTR-8/SVNEO) cells and the extravillous trophoblast outgrowth in placental explants.

CONCLUSIONS

Our results demonstrate for the first time the expression of ADAMTS13 mRNA and protein in normal and abnormal placental tissues and its role in promoting angiogenesis and trophoblastic cell development. The findings support the potential role of the ADAMTS13-von Willebrand factor pathway in normal pregnancy and pathogenesis of preeclampsia.

The ADAMTS hyalectanase family: biological insights from diverse species

The a disintegrin-like and metalloproteinase with thrombospondin type-1 motifs (ADAMTS) family of metzincins are complex secreted proteins that have diverse functions during development. The hyalectanases (ADAMTS1, 4, 5, 8, 9, 15 and 20) are a subset of this family that have enzymatic activity against hyalectan proteoglycans, the processing of which has important implications during development. This review explores the evolution, expression and developmental functions of the ADAMTS family, focusing on the ADAMTS hyalectanases and their substrates in diverse species. This review gives an overview of how the family and their substrates evolved from non-vertebrates to mammals, the expression of the hyalectanases and substrates in different species and their functions during development, and how these functions are conserved across species.

Role of Versican and ADAMTS-1 in Polycystic Ovary Syndrome

OBJECTIVE

ADAMTS-1 is a matrix metalloproteinase which cleaves versican in the cumulus oocyte complex under the effect of luteinizing hormone surge in the periovulatory period. Altered levels may have a role in the pathogenesis of polycystic ovary syndrome (PCOS). We aimed to determine the serum versican and ADAMTS-1 (a disintegrin and metalloproteinase with thrombospondin motif-1) levels in PCOS patients and compare the results with healthy controls.

METHODS

Thirty-eight patients with PCOS and forty healthy controls aged between 15 and 22 years were included in the study. They were sampled according to their basal hormone, serum versican, and ADAMTS-1 levels. Serum versican and ADAMTS-1 levels were measured by enzyme-linked immunosorbent assay. A multivariate logistic regression model was used to identify the independent risk factors of PCOS.

RESULTS

Serum versican levels were significantly decreased in the PCOS group when compared with the controls. The best versican cut-off value for PCOS was calculated to be 33.65 with 76.74% sensitivity and 52.94% specificity. Serum versican levels, homeostasis model assessment of insulin resistance index, a Ferriman-Gallwey score higher than 8, and oligomenorrhea were the strongest predictors of PCOS. Serum versican levels were significantly decreased in PCOS patients. Besides, serum ADAMTS-1 and versican levels were significantly and positively correlated with each other.

CONCLUSION

Serum versican levels were significantly decreased in patients with PCOS. This suggests a possible role of versican in ovulatory dysfunction and in the pathogenesis of PCOS.

Progesterone receptor and prostaglandins mediate luteinizing hormone-induced changes in messenger RNAs for ADAMTS proteases in theca cells of bovine periovulatory follicles

Little is known about the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family of extracellular proteases in ovarian follicles of non-rodent species, particularly in theca cells. In the present study, temporal changes in the abundance of mRNA encoding four ADAMTS subtypes and hormonal regulation of mRNA encoding two subtypes were investigated in theca interna cells during the periovulatory period in cattle. Gonadotropin-releasing hormone (GnRH) was injected into animals to induce a luteinizing hormone (LH)/follicle-stimulating hormone (FSH) surge, and follicles were obtained at 0 hr post-GnRH (preovulatory) or at 6, 12, 18, or 24 hr (periovulatory). ADAMTS1, -2, -7, and -9 transcript abundance was then determined in the isolated theca interna. ADAMTS1 and -9 mRNA levels were up-regulated at 24 hr post-GnRH, whereas ADAMTS2 mRNA was higher at 12-24 hr post-GnRH and ADAMTS7 mRNA increased transiently at 12 hr post-GnRH compared to other time points. Subsequent in vitro experiments using preovulatory theca interna (0 hr post-GnRH) showed that application of LH in vitro can mimic the effects of the gonadotropin surge on mRNAs encoding ADAMTS1 and -9 and that progesterone/progesterone receptor and/or prostaglandins may regulate the levels of mRNA encoding ADAMTS1 and -9 in theca interna, downstream of the LH surge. Time- and subtype-specific changes in ADAMTS mRNA abundance in vivo, and their regulation in vitro by hormones, indicate that ADAMTS family members produced by theca cells may play important roles in follicle rupture and the accompanying tissue remodeling in cattle. Mol. Reprod. Dev. 84: 55-66, 2017. © 2016 Wiley Periodicals, Inc.

Induction of Tissue Factor Pathway Inhibitor 2 by hCG Regulates Periovulatory Gene Expression and Plasmin Activity

Increased proteolytic activity is a key event that aids in breakdown of the follicular wall to permit oocyte release. How the protease activity is regulated is still unknown. We hypothesize that tissue factor pathway inhibitor 2 (TFPI2), a Kunitz-type serine protease inhibitor, plays a role in regulating periovulatory proteolytic activity as in other tissues. TFPI2 is secreted into the extracellular matrix (ECM) where it is postulated to regulate physiological ECM remodeling. The expression profile of TFPI2 during the periovulatory period was assessed utilizing a well-characterized human menstrual cycle model and a gonadotropin-primed rat model. Administration of an ovulatory dose of human chorionic gonadotropin (hCG) increased TFPI2 expression dramatically in human and rat granulosa and theca cells. This increase in Tfpi2 expression in rat granulosa cells required hCG-mediated epidermal growth factor, protein kinase A, mitogen-activated protein kinase (MAPK) 1/2, p38 MAPK and protease activated receptor 1-dependent cell signaling. A small interferingRNA-mediated knockdown of TFPI2 in rat granulosa cells resulted in increased plasmin activity in the granulosa cell conditioned media. Knockdown of TFPI2 also reduced expression of multiple genes including interleukin 6 (Il6) and amphiregulin (Areg). Overexpression of TFPI2 using an adenoviral vector partially restored the expression of Il6 and Areg in TFPI2 siRNA treated rat granulosa cells. These data support the hypothesis that TFPI2 is important for moderating plasmin activity and regulating granulosa cell gene expression during the periovulatory period. We, therefore, propose that through these actions, TFPI2 aids in the tissue remodeling taking place during follicular rupture and corpus luteum formation.

Clinical significance of ADAMTS1, ADAMTS5, ADAMTS9 aggrecanases and IL-17A, IL-23, IL-33 cytokines in polycystic ovary syndrome

PURPOSE

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders among women of reproductive age. A disintegrin and metalloproteinase with thrombospondin-like motifs (ADAMTS) are involved in inflammation and fertility. The aim of this investigation was to evaluate the serum levels of ADAMTS1, ADAMTS5, ADAMTS9, IL-17, IL-23, IL-33 and to find out the relationship between these inflammatory cytokines and ADAMTSs in PCOS patients.

METHODS

A case-control study was performed in a training and research hospital. Eighty patients with PCOS and seventy-eight healthy female volunteers were recruited in the present study. Serum ADAMTS and IL levels were determined by a human enzyme-linked immunoassay (ELISA) in all subjects.

RESULTS

The IL-17A, IL-23 and IL-33 levels were significantly higher in the PCOS patients compared to the controls (p < 0.05). We could not find significant difference between the groups in terms of ADAMTS1, ADAMTS5 and ADAMTS9 levels. IL-17A had positive correlations with LDL cholesterol and IL-33 and negative correlations with ADAMTS1, ADAMTS5, and ADAMTS9. IL-33 had positive correlation with LDL cholesterol and IL-17A. In ROC curve analysis, PCOS can be predicted by the use of IL-17A, IL-23 and IL-33 which at a cut-off value of 8.37 pg/mL (44 % sensitivity, 83 % specificity), 26.75 pg/mL (36 % sensitivity, 64 % specificity) and 14.28 pg/mL (83 % sensitivity, 39 % specificity), respectively.

CONCLUSIONS

The results of the study might suggest that ADAMTS and IL molecules have a role in the pathogenesis of the PCOS. Further efforts are needed to establish causality for ADAMTS-IL axis.

The spatiotemporal hormonal orchestration of human folliculogenesis, early embryogenesis and blastocyst implantation

The early reproductive events starting with folliculogenesis and ending with blastocyst implantation into the uterine endometrium are regulated by a complex interplay among endocrine, paracrine and autocrine factors. This review examines the spatiotemporal integration of these maternal and embryonic signals that are required for successful reproduction. In coordination with hypothalamic-pituitary-gonadal (HPG) hormones, an intraovarian HPG-like axis regulates folliculogenesis, follicular quiescence, ovulation, follicular atresia, and corpus luteal functions. Upon conception and passage of the zygote through the fallopian tube, the contribution of maternal hormones in the form of paracrine secretions from the endosalpinx to embryonic development declines, with autocrine and paracrine signaling becoming increasingly important as instructional signals for the differentiation of the early zygote/morula into a blastocyst. These maternal and embryonic signals include activin and gonadotropin-releasing hormone 1 (GnRH1) that are crucial for the synthesis and secretion of the 'pregnancy' hormone human chorionic gonadotropin (hCG). hCG in turn signals pre-implantation embryonic cell division and sex steroid production required for stem cell differentiation, and subsequent blastulation, gastrulation, cavitation and blastocyst formation. Upon reaching the uterus, blastocyst hatching occurs under the influence of decreased activin signaling, while the attachment and invasion of the trophoblast into the endometrium appears to be driven by a decrease in activin signaling, and by increased GnRH1 and hCG signaling that allows for tissue remodeling and the controlled invasion of the blastocyst into the uterine endometrium. This review demonstrates the importance of integrative endocrine, paracrine, and autocrine signaling for successful human reproduction.

Progesterone acts via the progesterone receptor to induce adamts proteases in ovarian cancer cells

BACKGROUND

Ovarian carcinomas, usually associated with sex hormones dysregulation, are the leading cause of gynecological neoplastic death. In normal ovaries, hormones play a central role in regulating cell proliferation, differentiation, and apoptosis. On the other hand, hormonal alterations also play a variety of roles in cancer. Stimulation by sex hormones potentially affects gene expression, invasiveness, cell growth and angiogenesis. Proteases of the "a disintegrin and metalloproteinase with thrombospondin motifs" (ADAMTS) family are secreted by different cell types and become involved in collagen processing, cleavage of the proteoglycan matrix, and angiogenesis. We evaluated whether sex hormones affect ADAMTS 1 and 4 expression in ovarian cancer cells.

METHODS

We analysed mRNA and protein levels in human ovarian tumor cells with different degrees of malignancy, NIH-OVCAR-3 and ES-2, that were treated or not with estrogen, testosterone and progesterone.

RESULTS

Our results suggest that progesterone increases ADAMTS protein and mRNA levels in the lysates from ES-2 cells, and it increases ADAMTS protein in the lysates and conditioned media from NIH-OVCAR-3. Progesterone effects were reversed by RU486 treatment.

CONCLUSION

We conclude that progesterone acts via the progesterone receptor to modulate ADAMTS 1 and 4 levels in ovarian cancer cell lines.

Ephrin-A5 Is Required for Optimal Fertility and a Complete Ovulatory Response to Gonadotropins in the Female Mouse

Follicle growth and ovulation involve the coordinated expression of many genes, driven by FSH and LH. Reports indicate that Eph receptors and ephrins are expressed in the ovary, suggesting roles in follicle growth and/or ovulation. We previously reported FSH-induced expression of ephrin-A5 (EFNA5) and 4 of its cognate Eph receptors in mouse granulosa cells. We now report that female mice lacking EFNA5 are subfertile, exhibit a compromised response to LH, and display abnormal ovarian histology after superovulation. Efna5(-/-) females litters were 40% smaller than controls, although no difference in litter frequency was detected. The ovarian response to superovulation was also compromised in Efna5(-/-) females, with 37% fewer oocytes ovulated than controls. These results corresponded with a reduction in ovarian mRNA levels of several LH-responsive genes, including Pgr, Ptgs2, Tnfaip6, Ereg, Btc, and Adamts4, suggesting that Efna5(-/-) ovaries exhibit a partially attenuated response to LH. Histopathological analysis indicated that superovulated Efna5(-/-) females exhibited numerous ovarian defects, including intraovarian release of cumulus oocyte complexes, increased incidence of oocytes trapped within luteinized follicles, granulosa cell and follicular fluid emboli, fibrin thrombi, and interstitial hemorrhage. In addition, adult Efna5(-/-) ovaries exhibited a 4-fold increase in multioocyte follicles compared with controls, although no difference was detected in 3-week-old mice, suggesting the possibility of follicle merging. Our observations indicate that loss of EFNA5 in female mice results in subfertility and imply that Eph-ephrin signaling may also play a previously unidentified role in the regulation of fertility in women.

ADAMTS proteases in fertility

The reproductive organs are unique among adult organs in that they must undergo continual tissue remodelling as a key aspect of their normal function. The processes for persistent maturation and release of new gametes, as well as fertilisation, implantation, placentation, gestation and parturition involve cyclic development and regression of tissues that must continually regenerate to support fertility. The ADAMTS family of proteases has been shown to contribute to many aspects of the tissue morphogenesis required for development and function of each of the reproductive organs. Dysregulation or functional changes in ADAMTS family proteases have been associated with reproductive disorders such as polycystic ovarian syndrome (PCOS) and premature ovarian failure (POF). Likewise, proteolytic substrates of ADAMTS enzymes have also been linked to reproductive function. New insight into the roles of ADAMTS proteases has yielded a deeper understanding of the molecular mechanisms behind fertility with clinical potential to generate therapeutic targets to resolve infertility, develop biomarkers that predict dysfunction of the reproductive organs and potentially offer targets for development of non-hormonal male and female contraceptives.

ADAMTS proteases in vascular biology

ADAMTS (a disintegrin and metalloprotease with thrombospondin motifs) proteases comprise the most recently discovered branch of the extracellular metalloenzymes. Research during the last 15years, uncovered their association with a variety of physiological and pathological processes including blood coagulation, tissue repair, fertility, arthritis and cancer. Importantly, a frequent feature of ADAMTS enzymes relates to their effects on vascular-related phenomena, including angiogenesis. Their specific roles in vascular biology have been clarified by information on their expression profiles and substrate specificity. Through their catalytic activity, ADAMTS proteases modify rather than degrade extracellular proteins. They predominantly target proteoglycans and glycoproteins abundant in the basement membrane, therefore their broad contributions to the vasculature should not come as a surprise. Furthermore, in addition to their proteolytic functions, non-enzymatic roles for ADAMTS have also been identified expanding our understanding on the multiple activities of these enzymes in vascular-related processes.

Progesterone receptor expression in granulosa cells is suppressed by microRNA-378-3p

In developing ovarian follicles, the progesterone receptor (PGR) is essential for mediating transcription of key factors that coordinate cellular functions including follicular remodeling. With recent investigations examining the role of microRNA (miRNA) in regulating ovarian function we used a lentiviral approach to over express miR-378 in cultured primary porcine granulosa cells to study the role this miRNA may play in granulosa cell development. We revealed that miR-378-3p decreased protein levels and mRNA levels of PGR via targeting its 3'UTR. We observed that this regulation of PGR by miR-378-3p resulted in a corresponding decrease in gene transcripts of ADAMTS1, CTSL1, and PPARG, all known to be regulated by PGR and important for follicular maturation and remodeling. Our study provides the first evidence for post-transcriptional regulation of PGR and further elucidates the role of miR-378-3p in the ovary.

A new biological marker candidate in female reproductive system diseases: Matrix metalloproteinase with thrombospondin motifs (ADAMTS)

Playing a key role in the pathophysiology of many diseases, A Disintegrin-like and Metalloproteinase with Thrombospondin type-1 motif (ADAMTS) proteinases have been attracted more attention in obstetrics and gynecology. First discovered in 1997, this zinc-dependent proteinase family has 19 members today. These enzymes, which are located in the extracellular matrix (ECM), have a lot of very important functions, like matrix formation and resorption, angiogenesis, ovulation, and coagulation. In addition, in the pathogenesis of cancer, inflammation, arthritis, and connective tissue diseases, ADAMTS proteinases have crucial roles. The purpose of this review is to collect previous studies about obstetrics and gynecology that are related to ADAMTS enzymes and discuss the subject in many aspects to give an idea to the investigators who are interested in the subject.

Interaction between thyroglobulin and ADAMTS16 in premature ovarian failure

Objective

The aim of the present study was to examine whether interactions between polymorphisms in the thyroglobulin and ADAM metallopeptidase with thrombospondin type 1 motif, 16 (ADAMTS16) genes are associated with the development of premature ovarian failure (POF).

Methods

A total of 75 patients with POF and 196 controls were involved in this study. We used a GoldenGate assay to genotype single nucleotide polymorphisms (SNPs). Logistic regression analysis was performed to identify POF-associated polymorphisms and synergistic interactions between polymorphisms in the thyroglobulin and ADAMTS16 genes.

Results

Single gene analyses using logistic regression analysis showed no significant association between polymorphisms in the two genes and POF. In the results from interaction analyses, we found seven synergistic interactions between the polymorphisms in thyroglobulin and ADAMTS16, although there was no combination showing p-values lower than the significant threshold using the Bonferroni correction. When the AG genotype was present at the rs853326 missense SNP, the A and G alleles at the tagging SNPs rs16875268 and rs13168665 showed significant interactions (odds ratios=5.318 and 16.2 respectively; 95% confidence intervals, 1.64-17.28 and 2.08-126.4; p=0.0054 and 0.0079).

Conclusion

Synergistic interactions between polymorphisms in the thyroglobulin and ADAMTS16 genes were associated with an increased risk of POF development in Korean women.

Cryptorchidism and infertility in rats with targeted disruption of the Adamts16 locus

A Disintegrin And Metalloproteinase with ThromboSpondin motifs16 (ADAMTS-16) is a member of a family of metalloproteinases. Using a novel zinc-finger nuclease based gene-edited rat model harboring a targeted mutation of the Adamts16 locus, we previously reported this gene to be linked to blood pressure regulation. Here we document our observation with this model that Adamts16 is essential for normal development of the testis. Absence of Adamts16 in the homozygous Adamts16^mutant males resulted in cryptorchidism and male sterility. Heterozygous Adamts16^mutant males were normal, indicating that this is a recessive trait. Testes of homozygous Adamts16^mutant males were significantly smaller with significant histological changes associated with the lack of sperm production. Temporal histological assessments of the testis demonstrated that the seminiferous tubules did not support active spermatogenesis, but progressively lost germ cells, accumulated vacuoles and did not have any sperm. These observations, taken together with our previous report of renal abnormalities observed with the same Adamts16^mutant rats, suggest an important mechanistic link between Adamts16 and the functioning of the male genitourinary system.