Lack of Serum anti-Mullerian hormone responses after recombinant human chorionic gonadotropin stimulation in women with polycystic ovary syndrome.

CONTEXT: Polycystic ovary syndrome (PCOS) is an anovulatory disorder characterized by excess androgen production and increased LH secretion. Serum anti-Mullerian hormone (AMH) is also elevated in this disorder. Women with PCOS exhibit a positive correlation between AMH and LH levels and recent in vitro data demonstrate that LH can directly stimulate AMH production by granulosa cells from women with PCOS. OBJECTIVE: The objective of the study was to directly test whether LH increases AMH production in women with PCOS in vivo by assessing responses after recombinant human chorionic gonadotropin (r-hCG) stimulation. DESIGN: This was a prospective study. SETTING: The study was conducted at a research center at an academic medical center. PARTICIPANTS: Women with PCOS (n = 28) and normal controls (n = 29) participated in the study. INTERVENTIONS: Blood samples were obtained before and 24 hours after iv administration of 25 µg r-hCG. MAIN OUTCOME MEASURES: Basal and stimulated serum AMH, androstenedione, T, and 17-hydroxyprogesterone levels were measured. RESULTS: Baseline AMH levels in women with PCOS were greater than in normal controls and correlated with levels of LH as well as androstenedione, T, and 17-hydroxyprogesterone. A rise of serum AMH levels was not observed after r-hCG administration in women with PCOS or normal ovaries. CONCLUSION: These findings are in contrast to in vitro evidence demonstrating that AMH secretion by granulosa cells of PCOS women in response to LH stimulation and suggest AMH regulation in vivo is complex and that the elevated serum AMH in women with PCOS is not a direct effect of the excess LH production characteristic of PCOS.

Metformin inhibits follicle-stimulating hormone (FSH) action in human granulosa cells: relevance to polycystic ovary syndrome.

BACKGROUND: Women with anovulatory polycystic ovary syndrome (PCOS) are generally insulin-resistant and as a consequence are often treated with the biguanide metformin. Results with metformin have, however, been variable with some studies demonstrating induction of regular cycles and an increase in ovulation, whereas others do not. Hence more understanding is needed regarding the mechanism of metformin's actions in ovarian granulosa cells especially in light of previous demonstrations of direct actions. OBJECTIVE: The aim of this study was to investigate metformin's interaction with the FSH/cAMP/protein kinase A pathway, which is the primary signaling pathway controlling CYP19A1 (aromatase) expression in the ovary. METHODS: The effect of metformin on FSH and forskolin-stimulated aromatase expression in human granulosa cells was measured by quantitative real-time PCR. Activity was assessed after transfection with a promoter II-luciferase construct, and by an RIA measuring conversion of androgen to estrogens. The effect on FSH receptor (FSHR) mRNA was assessed by quantitative PCR. Levels of phosphorylated cAMP response element binding protein (CREB) and CREB-regulated transcription coactivator 2 (CRTC2) were measured by Western blotting and cAMP by a bioluminescent assay. RESULTS: Metformin markedly reduced FSH but not forskolin-stimulated aromatase expression and activity. This effect was exerted by inhibition of basal and ligand-induced up-regulation of FSHR expression. Metformin also reduced FSH-induced phosphorylation of CREB and hence CRE activity, which could potentially disrupt the CREB-CREB-binding protein-CRTC2 coactivator complex that binds to CRE in promoter II of the aromatase gene. This is mediated in an AMP-activated protein kinase-independent manner, and does not involve alteration of cAMP levels. CONCLUSION: These finding have implications for the use of metformin in the treatment of anovulation in women with PCOS.

Ovarian 11ß-hydroxysteroid dehydrogenase (11ßHSD) activity is suppressed in women with anovulatory polycystic ovary syndrome (PCOS): apparent role for ovarian androgens.

CONTEXT: Altered hepatic cortisol-cortisone metabolism by type 1 11ß-hydroxysteroid dehydrogenase (11ßHSD1) has previously been linked with polycystic ovary (PCO) syndrome (PCOS). OBJECTIVES: Our objectives were to establish whether ovarian 11ßHSD activities are also altered in PCOS and to determine whether any changes in ovarian cortisol metabolism might reflect exposure to elevated concentrations of insulin or androgens. DESIGN: Cortisol and cortisone concentrations were measured in follicular fluid aspirated from size-matched follicles dissected from normal, ovulatory, and anovulatory PCOs. Human granulosa-lutein cells, recovered during oocyte retrieval for assisted conception, were maintained in primary culture for 4 days, after which 11ßHSD1 activities were measured as the net oxidation of [(3)H]cortisol (100 nmol/L) in the absence and presence of insulin (100 nmol/L) with or without metformin (1 µmol/L) or a range of androgens/oxy-androgen metabolites (0.01-10 µmol/L). RESULTS: Intrafollicular cortisol to cortisone ratios were elevated in anovulatory PCOs (2.1 ± 0.4, P < .05, n = 13) but did not differ between follicles from ovulatory PCOs (1.6 ± 0.1, n = 24) and normal ovaries (1.2 ± 0.1, n = 14). 11ßHSD1 activities were lower in granulosa-lutein cells recovered from patients with PCOS compared with all other causes of infertility (median = 5.8 vs 14.9 pmol cortisone/4 h, respectively; P < .05). Cortisol oxidation was unaffected by insulin with or without metformin, dehydroepiandrosterone, and androstenedione, but was inhibited in a concentration-dependent manner by testosterone, 11ß-hydroxyandrostenedione, and 7α- and 7ß-hydroxy-dehydroepiandrosterone (P < .01). CONCLUSIONS: There is decreased inactivation of cortisol in follicles from anovulatory PCOS. This may reflect inhibition of 11ßHSD1 by androgens and their 7/11-oxy-metabolites, local concentrations of which are increased in PCOS, and may contribute to the block to folliculogenesis seen in PCOS.

Anti-Müllerian hormone reduces follicle sensitivity to follicle-stimulating hormone in human granulosa cells.

OBJECTIVE: To determine that anti-Müllerian hormone (AMH) has been shown to inhibits E(2) production in rodents and in luteinized granulosa cells (GC). We determined whether this occurs in human cells most highly expressing AMH (i.e., from small antral follicles) and whether this is an effect on aromatase promoter activity. We also investigated the effects of AMH on other factors determining FSH sensitivity. DESIGN: Granulosa cells were exposed to AMH with and without gonadotropins for 48 hours. SETTING: University laboratory. PATIENT(S): Not applicable. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Aromatase and FSH receptor messenger RNA expression measured using real time quantitative polymerase chain reaction (PCR). Aromatase promoter II activity measured using a luciferase assay. Estradiol, inhibin A and B, and vascular endothelial growth factor production were measured in the conditioned medium. RESULT(S): The AMH decreased gonadotropin-stimulated aromatase expression and decreased forskolin-stimulated aromatase in KGN cells and this effect was through a dose-dependent inhibition of promoter II. Surprisingly, AMH also reduced FSH receptor mRNA expression. High AMH doses had no effect on inhibin B, whereas a low dose stimulated production. There was no effect on inhibin A or vascular endothelial growth factor. CONCLUSION(S): The AMH inhibits factors affecting FSH sensitivity. As AMH levels decrease with follicle growth, this inhibition would be removed. The AMH overproduction in anovulatory polycystic ovaries (PCO) may therefore restrict folliculogenesis by an inhibitory effect on FSH sensitivity, thereby contributing to anovulation.

Linkage of regulators of TGF-ß activity in the fetal ovary to polycystic ovary syndrome.

Although not often discussed, the ovaries of women with polycystic ovary syndrome (PCOS) show all the hallmarks of increased TGF-ß activity, with increased amounts of fibrous tissue and collagen in the ovarian capsule or tunica albuginea and ovarian stroma. Recent studies suggest that PCOS could have fetal origins. Genetic studies of PCOS have also found linkage with a microsatellite located in intron 55 of the extracellular matrix protein fibrillin 3. Fibrillins regulate TGF-ß bioactivity in tissues by binding latent TGF-ß binding proteins. We therefore examined expression of fibrillins 1-3, latent TGF-ß binding proteins 1-4, and TGF-ß 1-3 in bovine and human fetal ovaries at different stages of gestation and in adult ovaries. We also immunolocalized fibrillins 1 and 3. The results indicate that TGF-ß pathways operate during ovarian fetal development, but most important, we show fibrillin 3 is present in the stromal compartments of fetal ovaries and is highly expressed at a critical stage early in developing human and bovine fetal ovaries when stroma is expanding and follicles are forming. These changes in expression of fibrillin 3 in the fetal ovary could lead to a predisposition to develop PCOS in later life.

Anti-Müllerian hormone and polycystic ovary syndrome: a mountain too high?

Anti-Müllerian hormone (AMH) was initially thought to be produced solely by the foetal male during sexual differentiation to promote regression of the Müllerian ducts. Over the last decade, however, a new and interesting role has emerged for AMH in the ovary. In human ovaries, AMH is produced by granulosa cells from 36 weeks of gestation until menopause, with the highest expression being in small antral follicles. AMH production gradually declines as follicles grow; once follicles reach a size at which they are dominant, it has largely disappeared. Its removal from these larger follicles appears to be an important requirement for dominant follicle selection and progression to ovulation as AMH has an inhibitory role in the ovary, reducing both primordial follicle initiation and follicle sensitivity to FSH by inhibition of aromatase. It is for this reason that AMH is a focus of interest in polycystic ovary syndrome (PCOS). Serum levels are doubled, and granulosa cell production is greatly increased. Interestingly, there appear to be two groups of women with PCOS who can be distinguished by their AMH level: one group consists of those who have high levels which do not reduce with treatment and who respond less well to induction of ovulation, and a second group consists of those in whom the level is less elevated and reduces on treatment and who seem to respond rather better. Understanding the reason for the raised AMH in PCOS may give clues as to the mechanism of anovulation. To conclude, AMH appears to have a major inhibitory role during folliculogenesis, which may contribute to anovulation in PCOS.

Genetic and gene expression analyses of the polycystic ovary syndrome candidate gene fibrillin-3 and other fibrillin family members in human ovaries.

Several studies have demonstrated an association between polycystic ovary syndrome (PCOS) and the dinucleotide repeat microsatellite marker D19S884, which is located in intron 55 of the fibrillin-3 (FBN3) gene. Fibrillins, including FBN1 and 2, interact with latent transforming growth factor (TGF)-beta-binding proteins (LTBP) and thereby control the bioactivity of TGFbetas. TGFbetas stimulate fibroblast replication and collagen production. The PCOS ovarian phenotype includes increased stromal collagen and expansion of the ovarian cortex, features feasibly influenced by abnormal fibrillin expression. To examine a possible role of fibrillins in PCOS, particularly FBN3, we undertook tagging and functional single nucleotide polymorphism (SNP) analysis (32 SNPs including 10 that generate non-synonymous amino acid changes) using DNA from 173 PCOS patients and 194 controls. No SNP showed a significant association with PCOS and alleles of most SNPs showed almost identical population frequencies between PCOS and control subjects. No significant differences were observed for microsatellite D19S884. In human PCO stroma/cortex (n = 4) and non-PCO ovarian stroma (n = 9), follicles (n = 3) and corpora lutea (n = 3) and in human ovarian cancer cell lines (KGN, SKOV-3, OVCAR-3, OVCAR-5), FBN1 mRNA levels were approximately 100 times greater than FBN2 and 200-1000-fold greater than FBN3. Expression of LTBP-1 mRNA was 3-fold greater than LTBP-2. We conclude that FBN3 appears to have little involvement in PCOS but cannot rule out that other markers in the region of chromosome 19p13.2 are associated with PCOS or that FBN3 expression occurs in other organs and that this may be influencing the PCOS phenotype.

Phenotypes of the ovarian follicular basal lamina predict developmental competence of oocytes.

BACKGROUND: The ovarian follicular basal lamina underlies the epithelial membrana granulosa and maintains the avascular intra-follicular compartment. Additional layers of basal lamina occur in a number of pathologies, including pili annulati and diabetes. We previously found additional layers of follicular basal lamina in a significant percentage of healthy bovine follicles. We wished to determine if this phenomenon existed in humans, and if it was related to oocyte function in the bovine. METHODS AND RESULTS: We examined follicles from human ovaries (n = 18) by electron microscopy and found that many follicles had additional layers of basal lamina. Oocytes (n = 222) from bovine follicles with normal or unusual basal laminas were isolated and their ability to undergo in vitro maturation, fertilization and culture to blastocyst was compared. Healthy bovine follicles with a single layer of basal lamina had oocytes with significantly (P < 0.01) greater developmental competence than healthy follicles with additional layers of follicular basal lamina (65% versus 28%). CONCLUSIONS: These findings provide direct evidence that the phenotype of the follicular basal lamina is related to oocyte competence.

Pelvic ultrasonography in anorexia nervosa: what the clinician should ask the radiologist and how to use the information provided.

Pelvic ultrasonography is generally regarded as the gold standard for determination of pelvic maturity and hence the need for further weight gain in patients with anorexia nervosa. Many clinicians, however, have limited knowledge of this technique. Here, we describe the use of pelvic ultrasonography in anorexia nervosa and present an algorithm to assist the clinician, both with what questions to ask from the radiologist, and how to use the information provided to determine the morphology and hence maturity of the pelvic organs. We then show how this information can be used to assign the level of pelvic maturity a grade from 1 to 5. Finally, we demonstrate use of this system in two patients who progressively gained weight until pelvic maturity was achieved.

Phytoestrogens and their low dose combinations inhibit mRNA expression and activity of aromatase in human granulosa-luteal cells.

There is evidence that certain phytoestrogens inhibit aromatase, the enzyme that converts androgens to oestrogens. Kinetic studies in cell-free preparations show that they may inhibit aromatase by competitive binding to the enzyme, but there is a paucity of studies investigating longer-term effects of phytoestrogens on the expression of steroidogenic enzymes. This study tested the hypothesis that phytoestrogens could reduce aromatase activity by down-regulation of its expression. Experiments were carried out on primary cultures of human granulosa-luteal (GL) cells after they had been exposed to phytoestrogens for 48 h. Aromatase activity was measured by the ability of cells to convert testosterone to estradiol over a 4h period and aromatase mRNA expression (mRNA(arom)) was subsequently measured from the same cells using quantitative real-time PCR. The compounds investigated were the flavones, apigenin and quercetin, and the isoflavones, genistein, biochanin A and daidzein at doses of 10 microM and 100 nM. Combinations of these compounds at the lower dose were also investigated. All compounds tested dose-dependently reduced mean mRNA(arom) compared with controls. Apigenin was the most potent inhibitor with significant inhibition of mRNA(arom) seen at both 10 microM and 100 nM, whilst other flavonoids (except biochanin A) only induced significant inhibition (p

Extracellular matrix of the human cyclic corpus luteum.

Extracellular matrix regulates many cellular processes likely to be important for development and regression of corpora lutea. Therefore, we identified the types and components of the extracellular matrix of the human corpus luteum at different stages of the menstrual cycle. Two different types of extracellular matrix were identified by electron microscopy; subendothelial basal laminas and an interstitial matrix located as aggregates at irregular intervals between the non-vascular cells. No basal laminas were associated with luteal cells. At all stages, collagen type IV alpha1 and laminins alpha5, beta2 and gamma1 were localized by immunohistochemistry to subendothelial basal laminas, and collagen type IV alpha1 and laminins alpha2, alpha5, beta1 and beta2 localized in the interstitial matrix. Laminin alpha4 and beta1 chains occurred in the subendothelial basal lamina from mid-luteal stage to regression; at earlier stages, a punctate pattern of staining was observed. Therefore, human luteal subendothelial basal laminas potentially contain laminin 11 during early luteal development and, additionally, laminins 8, 9 and 10 at the mid-luteal phase. Laminin alpha1 and alpha3 chains were not detected in corpora lutea. Versican localized to the connective tissue extremities of the corpus luteum. Thus, during the formation of the human corpus luteum, remodelling of extracellular matrix does not result in basal laminas as present in the adrenal cortex or ovarian follicle. Instead, novel aggregates of interstitial matrix of collagen and laminin are deposited within the luteal parenchyma, and it remains to be seen whether this matrix is important for maintaining the luteal cell phenotype.

Health-related quality of life in women with polycystic ovary syndrome: a comparison with the general population using the Polycystic Ovary Syndrome Questionnaire (PCOSQ) and the Short Form-36 (SF-36).

BACKGROUND: We examined whether women with polycystic ovary syndrome (PCOS) have poorer health-related quality of life (HRQoL) than women in the general population and than patients with other medical conditions. METHOD: Women with PCOS were recruited from an outpatient clinic and a control group was recruited from a family planning clinic. Both groups completed the Short Form-36 (SF-36) and the Polycystic Ovary Syndrome Questionnaire (PCOSQ). SF-36 data from the Oxford Health and Lifestyle Survey were used to compare PCOS with other conditions. RESULTS: Twenty-two women with PCOS and 96 control women took part. Women with PCOS scored lower in both summary scores of the SF-36 and in all domains of the PCOSQ. After adjusting for body mass index, the differences between the groups in the SF-36 disappeared, while those in the PCOSQ remained. When compared with asthma, epilepsy, diabetes, back pain, arthritis and coronary heart disease, our PCOS group had the same or better physical HRQoL but poorer psychological HRQoL. The PCOSQ showed good internal reliability, good concurrent validity and good discriminant validity. CONCLUSIONS: PCOS has a negative impact on HRQoL even when compared with other serious health conditions. The PCOSQ is reliable and valid for clinical use.

Selection of gonadotrophin surge attenuating factor phage antibodies by bioassay.

BACKGROUND: We aimed to combine the generation of "artificial" antibodies with a rat pituitary bioassay as a new strategy to overcome 20 years of difficulties in the purification of gonadotrophin surge-attenuating factor (GnSAF). METHODS: A synthetic single-chain antibody (Tomlinson J) phage display library was bio-panned with partially purified GnSAF produced by cultured human granulosa/luteal cells. The initial screening with a simple binding immunoassay resulted in 8 clones that were further screened using our in-vitro rat monolayer bioassay for GnSAF. Initially the antibodies were screened as pooled phage forms and subsequently as individual, soluble, single-chain antibody (scAbs) forms. Then, in order to improve the stability of the scAbs for immunopurification purposes, and to widen the range of labelled secondary antibodies available, these were engineered into full-length human immunoglobulins. The immunoglobulin with the highest affinity for GnSAF and a previously described rat anti-GnSAF polyclonal antiserum was then used to immunopurify bioactive GnSAF protein. The two purified preparations were electrophoresed on 1-D gels and on 7 cm 2-D gels (pH 4-7). The candidate GnSAF protein bands and spots were then excised for peptide mass mapping. RESULTS: Three of the scAbs recognised GnSAF bioactivity and subsequently one clone of the purified scAb-derived immunoglobulin demonstrated high affinity for GnSAF bioactivity, also binding the molecule in such as way as to block its bioactivity. When used for repeated immunopurification cycles and then Western blot, this antibody enabled the isolation of a GnSAF-bioactive protein band at around 66 kDa. Similar results were achieved using the rat anti-GnSAF polyclonal antiserum. The main candidate molecules identified from the immunopurified material by excision of 2-D gel protein spots was human serum albumin precursor and variants. CONCLUSION: This study demonstrates that the combination of bioassay and phage display technologies is a powerful tool in the study of uncharacterised proteins that defy conventional approaches. In addition, we conclude that these data support suggestions that GnSAF may be structurally related to serum albumin or very tightly bound to serum albumin.

Ovarian gonadotrophin surge-attenuating factor (GnSAF): where are we after 20 years of research?

When gonadotrophin-stimulated IVF methods were being developed in the 1970s and 1980s, understanding of the physiology of FSH improved. In addition to its classic actions of stimulating aromatase activity and oestradiol secretion by ovarian granulosa cells, FSH was found to stimulate the ovarian production of an uncharacterized hormone known by its specific effect of reducing pituitary responsiveness to GnRH. This hormone has been called gonadotrophin surge-attenuating factor (GnSAF), gonadotropin surge-inhibiting factor (GnSIF), various abbreviations (GnSAF/IF, GnSIF/AF) and also attenuin. Although first described in the 1980s, GnSAF has still not been convincingly characterized and no published candidate amino acid sequences conclusively relate to GnSAF bioactivity. On the basis of superovulation studies and in vitro experimentation into the roles of steroids in regulating LH, GnRH and GnRH self-priming, the concept that GnSAF has a role in the regulation of LH secretion, the timing of the LH surge and the prevention of premature luteinization developed. For at least a decade, understanding of the specific GnSAF effects of reducing pituitary sensitivity to GnRH, especially GnRH self-priming and antagonizing the stimulatory effects of oestradiol on GnRH-induced LH secretion, supported this concept. However, improved knowledge of the changes in GnSAF bioactivity in follicular fluid and serum in women requires revision of this concept. The present authors propose that the main role of GnSAF is probably the negative regulation of pulsatile LH secretion, mainly during the first half of the follicular phase, indicating a critical role in the regulation of folliculogenesis and oestradiol secretion.

A 60-66 kDa protein with gonadotrophin surge attenuating factor bioactivity is produced by human ovarian granulosa cells.

We aimed to confirm the ovarian site of gonadotrophin surge-attenuating factor (GnSAF) production and produce granulosa/luteal cell-conditioned medium (G/LCM) containing GnSAF for purification studies. Blue dye affinity chromatography followed by pseudochromatofocusing of G/LCM yielded bioactive fractions at pH 5.74 and 5.77. The former had a major 60-66 kDa band with an internal amino acid sequence of EPQVYVHAP following tryptic digestion. A rat polyclonal antiserum (rPAb) raised against this band completely blocked in-vitro GnSAF bioactivity in human follicular fluid, serum and G/LCM. GnSAF bioactivity was localized to a 64 kDa band of serum-free G/LCM and following 2D gel electrophoresis, one of the spots recognized by Western blotting with the GnSAF rPAb had an N-terminal amino acid sequence of NH-XVPQGNAXXN. Neither amino acid sequence had significant homology with proteins in the human genome database. When ovarian tissues from spontaneously cycling women were cultured under serum-free conditions, neither theca- nor stroma-conditioned media contained GnSAF bioactivity. However, granulosa cell-conditioned medium significantly reduced GnRH-induced LH secretion, an effect that was reversed by incubation with the GnSAF rPAb. In conclusion, we have confirmed that human granulosa cells produce GnSAF within the ovary and have two candidate amino acid sequences for GnSAF. We have also demonstrated that serum-free granulosa cell culture constitutes the method of choice for the characterization of GnSAF since recovery of bioactivity is superior in the presence of fewer serum proteins.

Insulin-like growth factor (IGF)-independent effects of IGF binding protein-4 on human granulosa cell steroidogenesis.

The ovarian insulin-like growth factor (IGF)/IGF binding protein (IGFBP) system operates to permit maximal stimulation of steroidogenesis in the dominant follicle. In atretic follicles, the predominant IGFBPs are IGFBP-2 and IGFBP-4, which appear to be selectively cleaved in healthy follicles. We have recently demonstrated potent inhibition by IGFBP-4 of both theca and granulosa cell steroid production. The degree to which the inhibition occurred suggested that it was greater than might be expected by sequestration of IGF alone. Our study was designed to test this idea. Granulosa cells were harvested from follicles dissected intact from patients undergoing total abdominal hysterectomy and bilateral salpingoophorectomy. Granulosa cells were incubated with or without gonadotropins and IGFBP-4 in the presence or absence of either the IGF type I receptor blocker alphaIR3 or excess IGFBP-3 to remove the effects of endogenous IGF action. Steroid accumulation in the medium was assessed. IGFBP-4 continued to exert potent inhibitory effects when the action of endogenous IGF was removed from the system, demonstrating that its actions are independent of IGF binding. There was no effect on cell metabolism, and the effects on steroidogenesis were reversible after IGFBP-4 removal from the culture medium. No similar effects were seen with IGFBP-2. These reasults are the first evidence of IGF-independent IGFBP-4 actions and the first evidence of IGF-independent actions of any IGFBPs in the ovary.