Decreased inhibin B responses following recombinant human chorionic gonadotropin administration in normal women and women with polycystic ovary syndrome

OBJECTIVE

To determine whether granulosa cells contribute to excess androgen production, by assessing inhibin B (Inh B) responses to hCG in women with polycystic ovary syndrome (PCOS) and in normal women.

DESIGN

Prospective study.

SETTING

Academic medical center.

PATIENT(S)

Twenty women with PCOS and 16 normal women.

INTERVENTION(S)

Blood samples obtained before and 24 hours after injection of 25 μg recombinant hCG (r-hCG).

MAIN OUTCOME MEASURE(S)

Basal and stimulated Inh B, E2, androstenedione (A), and T responses after r-hCG administration.

RESULT(S)

In normal and PCOS women, r-hCG induced a significant reduction of Inh B levels. Lowered Inh B responses were not related to body mass index, PCOS status, or age by multivariate regression. Recombinant hCG significantly increased serum A and E2 in both normal and PCOS women.

CONCLUSION(S)

In normal and PCOS women, Inh B production was decreased following r-hCG administration. These findings strongly suggest that in PCOS women androgen excess is not enhanced by LH-stimulated Inh B production.

CLINICAL TRIAL REGISTRATION NUMBER

NCT00747617.

Disordered follicle development

Alterations of ovarian follicle morphology and function have been well documented in women with PCOS. These include increased numbers of growing preantral follicles, failure of follicle growth beyond the mid-antral stage, evidence of granulosa call degeneration, and theca cell hyperplasia. Functional abnormalities include paradoxical granulosa cell hyperresponsiveness to FSH which is clinically linked to ovarian hyperstimulation during ovulation induction. In addition, there is likely a primary theca cell defect that accounts for the majority of excess androgen production in this disorder. The precise mechanisms responsible for altered follicle function are not completely clear. However, several factors appear to influence normal advancement of follicle development as well as impair ovarian steroidogenesis. These include intra- as well as extraovarian influences that distort normal ovarian growth and disrupt steroid production by follicle cells.

Paracrine regulation of theca androgen production by granulosa cells in the ovary

OBJECTIVE

To test whether and to what extent inhibin mediates Cyp17 messenger RNA (mRNA) expression in theca cells (TCs) in response to FSH stimulation of granulosa cells (GCs).

DESIGN

Ex vivo and in vitro experimental study.

SETTING

University.

ANIMAL(S)

Immature female Sprague Dawley rats.

INTERVENTION(S)

Ovarian tissue explants and isolated theca cell preparations with or without GCs were treated with FSH, inhibin, inhibin antibody, or β-glycan antibody.

MAIN OUTCOME MEASURE(S)

As a key enzyme in androgen production, Cyp17 mRNA levels were measured by real-time reverse transcription-polymerase chain reaction.

RESULT(S)

After 24 hours, Cyp17 mRNA expression was dose-dependently increased by FSH in ovarian tissue explants and theca cells, suggesting that paracrine factor(s) secreted from GCs in response to FSH mediates Cyp17 mRNA expression in TCs. Antibodies against inhibin and inhibin coreceptor, β-glycan, blocked the stimulatory effect of FSH on Cyp17 mRNA expression. However, inhibin alone did not increase Cyp17 mRNA level to the same extent.

CONCLUSION(S)

These findings suggest a role for inhibin in the paracrine regulation of TC Cyp17 mRNA expression by GCs influenced by FSH; however, other paracrine factors produced by GCs by virtue of FSH seem to be required.

The RHOX homeobox gene cluster is selectively expressed in human oocytes and male germ cells

STUDY QUESTION

What human tissues and cell types express the X-linked reproductive homeobox (RHOX) gene cluster?

SUMMARY ANSWER

The RHOX homeobox genes and proteins are selectively expressed in germ cells in both the ovary and testis.

WHAT IS KNOWN ALREADY

The RHOX homeobox transcription factors are encoded by an X-linked gene cluster whose members are selectively expressed in the male and female reproductive tract of mice and rats. The Rhox genes have undergone strong selection pressure to rapidly evolve, making it uncertain whether they maintain their reproductive tissue-centric expression pattern in humans, an issue we address in this report.

STUDY DESIGN, SIZE, DURATION

We examined the expression of all members of the human RHOX gene cluster in 11 fetal and 8 adult tissues. The focus of our analysis was on fetal testes, where we evaluated 16 different samples from 8 to 20 weeks gestation. We also analyzed fixed sections from fetal testes, adult testes and adult ovaries to determine the cell type-specific expression pattern of the proteins encoded by RHOX genes.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We used quantitative reverse transcription-polymerase chain reaction analysis to assay human RHOX gene expression. We generated antisera against RHOX proteins and used them for western blotting, immunohistochemical and immunofluorescence analyses of RHOXF1 and RHOXF2/2B protein expression.

MAIN RESULTS AND THE ROLE OF CHANCE

We found that the RHOXF1 and RHOXF2/2B genes are highly expressed in the testis and exhibit low or undetectable expression in most other organs. Using RHOXF1- and RHOXF2/2B-specific antiserum, we found that both RHOXF1 and RHOXF2/2B are primarily expressed in germ cells in the adult testis. Early stage germ cells (spermatogonia and early spermatocytes) express RHOXF2/2B, while later stage germ cells (pachytene spermatocytes and round spermatids) express RHOXF1. Both RHOXF1 and RHOXF2/2B are expressed in prespermatogonia in human fetal testes. Consistent with this, RHOXF1 and RHOXF2/2B mRNA expression increases in the second trimester during fetal testes development when gonocytes differentiate into prespermatogonia. In the human adult ovary, we found that RHOXF1 and RHOXF2/2B are primarily expressed in oocytes.

LIMITATIONS, REASONS FOR CAUTION

While the average level of expression of RHOX genes was low or undetectable in all 19 human tissues other than testes, it is still possible that RHOX genes are highly expressed in a small subset of cells in some of these non-testicular tissues. As a case in point, we found that RHOX proteins are highly expressed in oocytes within the human ovary, despite low levels of RHOX mRNA in the whole ovary.

WIDER IMPLICATIONS OF THE FINDINGS

The cell type-specific and developmentally regulated expression pattern of the RHOX transcription factors suggests that they perform regulatory functions during human fetal germ cell development, spermatogenesis and oogenesis. Our results also raise the possibility that modulation of RHOX gene levels could correct some cases of human infertility and that their encoded proteins are candidate targets for contraceptive drug design.

Future Directions in Oncofertility and Fertility Preservation: A Report from the 2011 Oncofertility Consortium Conference

Fertility impairment and loss due to cancer or its treatment is a significant survivorship consideration for many pediatric, adolescent, and young adult cancer survivors. Chemotherapeutics, radiation, and surgery can impact the future fertility of men, women, and children with cancer. The field of oncofertility, founded to ensure the reproductive future of cancer survivors, gained momentum with 5 years of funding through a 2007 National Institutes of Health Roadmap Grant for Biomedical Research. This report from working group meetings at the fifth annual Oncofertility Consortium Conference speaks to the present state of oncofertility research and clinical care, existing gaps, and future directions for the field. This summary from conference participants and leaders in the field addresses the science, clinical specialties, and academic scholarship that can guide the field as the Roadmap Grant funding comes to a close.

Ovarian imaging by magnetic resonance in adolescent girls with polycystic ovary syndrome and age-matched controls

PURPOSE

To compare ovarian morphology in adolescent girls with and without polycystic ovary syndrome (PCOS) using magnetic resonance imaging (MRI).

MATERIALS AND METHODS

In 21 adolescent girls (age 12-18 years) without and 19 adolescents with PCOS (diagnosis based on excessive hair growth and irregular menstrual cycles) ovarian volume, antral follicle count (AFC) per ovary, and follicle size were evaluated. MRI was performed at 1.5 T or 3 T and axial or angled-axial single-shot echo-train spin echo images of 6 mm slice thickness were acquired. In a subset of subjects, 2-mm images were also obtained. PCOS and non-PCOS groups were compared using mixed affects regression.

RESULTS

Mean AFC per ovary and ovarian volume were substantially greater in PCOS subjects compared to non-PCOS subjects. Mean follicle size was similar between groups. Follicles exceeding 10 mm were seen in 2/19 PCOS subjects versus 9/21 non-PCOS subjects. Consistently higher follicle counts were detected in images obtained at 2 mm compared to 6-mm slice thickness.

CONCLUSION

In adolescence, MRI of the ovary reveals distinct differences between girls with and without PCOS. MRI may help evaluate young patients in whom transvaginal ultrasound is contraindicated.

Distinct developmental signatures of human abdominal and gluteal subcutaneous adipose tissue depots

CONTEXT

Fat distribution differs in men and women, but in both sexes, a predominantly gluteal-femoral compared with abdominal (central) fat distribution is associated with lower metabolic risk. Differences in cellular characteristics and metabolic functions of these depots have been described, but the molecular mechanisms involved are not understood.

OBJECTIVE

Our objective was to identify depot- and sex-dependent differences in gene expression in human abdominal and gluteal sc adipose tissues.

DESIGN AND METHODS

Abdominal and gluteal adipose tissue aspirates were obtained from 14 premenopausal women [age 27.5 ± 7.0 yr, body mass index (BMI) 27.3 ± 6.2 kg/m(2), and waist-to-hip ratio 0.82 ± 0.04] and 21 men (age 29.7±7.4 yr, BMI 27.2 ± 4.5 kg/m(2), and waist-to-hip ratio 0.91 ± 0.07) and transcriptomes were analyzed using Illumina microarrays. Expression of selected genes was determined in isolated adipocytes and stromal vascular fractions from each depot, and in in vitro cultures before and after adipogenic differentiation.

RESULTS

A total of 284 genes were differentially expressed between the abdominal and gluteal depot, either specifically in males (n = 66) or females (n = 159) or in both sexes (n = 59). Most notably, gene ontology and pathway analysis identified homeobox genes (HOXA2, HOXA3, HOXA4, HOXA5, HOXA9, HOXB7, HOXB8, HOXC8, and IRX2) that were down-regulated in the gluteal depot in both sexes (P = 2 × 10(-10)). Conversely, HOXA10 was up-regulated in gluteal tissue and HOXC13 was detected exclusively in this depot. These differences were independent of BMI, were present in both adipocytes and stromal vascular fractions of adipose tissue, and were retained throughout in vitro differentiation.

CONCLUSIONS

We conclude that developmentally programmed differences may contribute to the distinct phenotypic characteristics of peripheral fat.

Elevated androgens during puberty in female rhesus monkeys lead to increased neuronal drive to the reproductive axis: a possible component of polycystic ovary syndrome

BACKGROUND

Hyperandrogenemia is associated with several clinical disorders in which both reproductive dysfunction and metabolic changes may coexist [i.e. polycystic ovary syndrome (PCOS), obesity and congenital adrenal hyperplasia]. Moreover, there is growing evidence that the elevated levels of circulating androgens in obese girls may lead to an increased neuroendocrine drive to the reproductive axis, similar to that associated with PCOS.

METHODS

To test whether androgen exposure in the childhood and adolescent period could lead to pubertal alterations in LH secretory patterns, female rhesus monkeys received subcutaneous testosterone implants prepubertally beginning at 1 year of age, maintaining a 3.7-fold increase (P = 0.001) in circulating testosterone levels over cholesterol-implant controls (n = 6/group) into the post-pubertal period. In early adulthood, pulsatile secretion of LH was measured over 12 h during the early follicular phase of a menstrual cycle, and responsiveness of the pituitary to gonadotrophin-releasing hormone was determined. In addition, ultrasounds were performed to assess ovarian morphology and glucose tolerance testing was performed to assess insulin sensitivity.

RESULTS

The timing of menarche was similar between groups. Testosterone-treated animals had a significantly greater LH pulse frequency during the early follicular phase compared with controls (P = 0.039) when measured at 5 years of age. There was a larger LH response to GnRH when testosterone-treated animals were 4 years of age (P = 0.042), but not when the animals were 5 years old (P = 0.57). No differences were seen in insulin sensitivity or ovarian morphology, and the groups showed similar rates of ovulation in early adulthood.

CONCLUSIONS

Exposure to increased levels of androgens over the course of pubertal development appears to trigger physiological changes in the neural drive to the reproductive axis that resemble those of obese hyperandrogenemic girls in early adulthood and are characteristic of PCOS.

Clinical evidence for predominance of delta-5 steroid production in women with polycystic ovary syndrome

CONTEXT

In women with polycystic ovary syndrome (PCOS), the basis for ovarian androgen overproduction involves an overall increase of steroidogenesis, notably in the delta-4 pathway. However, in vitro studies have suggested that excessive androgen production occurs predominantly through the delta-5 pathway.

OBJECTIVE

This study was performed to assess androgen dose-responses after human chorionic gonadotropin (hCG) stimulation in PCOS and normal women.

DESIGN

We conducted a prospective study to compare androgen production after iv hCG in PCOS and normal women.

SETTING

The study was conducted in a General Clinical Research Center in an academic medical center.

PARTICIPANTS

Women with PCOS (age, 18-37 yr; n = 10) and normal ovulatory controls (age, 18-37 yr; n = 11) were recruited.

INTERVENTIONS

For dose-response studies, blood samples were obtained before and at 0.5, 24, and 48 h after iv recombinant hCG (1, 10, 25, 100, and 250 μg). A subset of subjects underwent frequent blood sampling over 24 h after iv injection of 25 μg of recombinant hCG.

MAIN OUTCOME MEASURE(S)

We measured basal and stimulated serum 17-hydroxyprogesterone (17-OHP), androstenedione (A), testosterone (T), dehydroepiandrosterone, estradiol, and progesterone responses after hCG administration.

RESULTS

In PCOS women, maximal A and T production was observed at the lowest doses of hCG, whereas responses were minimal in normal women. Incremental responses of 17-OHP, estradiol, and progesterone were greater in PCOS compared to normal women.

CONCLUSION

In PCOS women, maximal A and T responses to hCG relative to those of 17-OHP are consistent with ovarian androgen overproduction via the delta-5 pathway.

Hyperandrogenemia in obese peripubertal girls: correlates and potential etiological determinants

Obesity in peripubertal girls is associated with hyperandrogenemia (HA), which can represent a forerunner of polycystic ovary syndrome (PCOS). However, not all obese girls demonstrate HA, and determinants of HA in obese girls remain unclear. We hypothesized that insulin and luteinizing hormone (LH) are independent predictors of free testosterone (T) concentration in obese girls. To assess this further, fasting morning blood samples were collected from 92 obese (BMI-for-age percentile ≥95) girls in various stages of puberty. A multivariate regression model was then constructed using free T (dependent variable), LH, insulin, pubertal group (early, mid-, or late puberty), BMI z-score, and age. Free testosterone (T) concentrations were highly variable among obese girls in each pubertal group. The regression model accounted for roughly half of the variability of free T in obese girls (adjusted R(2) = 0.53, P < 0.001). LH was found to have the greatest independent ability to predict free T, followed by insulin, then age and BMI z-score. Pubertal group was not an independent predictor of free T. We conclude that morning LH and fasting insulin are significant predictors of free T in obese girls, even after adjusting for potential confounders (age, pubertal group, adiposity). We suggest that abnormal LH secretion and hyperinsulinemia can promote HA in some peripubertal girls with obesity.

Polycystic ovary syndrome and acne

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in reproductive aged women. It is typically characterized by hyperandrogenism, chronic anovulation, and polycystic ovaries. Women with PCOS often experience dermatologic manifestations of hyperandrogenism, including hirsutism, acne vulgaris, and androgenic alopecia. This article will review the treatments for acne due to androgen excess in PCOS women.

Serum anti-mullerian hormone concentrations are elevated in oligomenorrheic girls without evidence of hyperandrogenism

CONTEXT

Serum anti-Müllerian hormone (AMH) levels are significantly elevated in adolescents with polycystic ovary syndrome (PCOS) compared to normal controls. Whether adolescents with oligomenorrhea have elevated AMH levels is unknown.

OBJECTIVE

This study was performed to assess serum AMH levels in oligomenorrheic (OLIGO) girls without evidence of hyperandrogenism.

DESIGN

This was a prospective study comparing AMH levels in OLIGO, PCOS, and normal control adolescents.

SETTING

The study was conducted through four tertiary academic medical centers.

PARTICIPANTS

The study groups were comprised of OLIGO (n = 24), PCOS (n = 153), and normal adolescent girls (n = 39), as well as PCOS (n = 73) and normal adult women (n = 36).

INTERVENTIONS

In each subject, serum AMH levels were assessed in the early to midfollicular phases for regularly menstruating subjects and on an arbitrary day for OLIGO or PCOS subjects.

MAIN OUTCOME MEASURE(S)

Basal serum AMH levels were assessed among OLIGO, PCOS, and normal girls, in addition to PCOS and normal women.

RESULTS

OLIGO girls had serum AMH levels (5.33 +/- 0.47 ng/ml) that were significantly greater than the normal adolescents (3.05 +/- 0.31 ng/ml) and adults (2.33 +/- 0.22 ng/ml), but similar to values seen in the PCOS adolescents (5.28 +/- 0.26 ng/ml) and adults (6.36 +/- 0.47 ng/ml). Obese adolescents and PCOS women had significantly lower AMH levels compared to lean controls (P < 0.02).

CONCLUSION

In OLIGO adolescents, elevated serum AMH levels suggest increased antral follicle number similar to that observed in girls with PCOS.

Comparison of inhibin B and estradiol responses to intravenous FSH in women with polycystic ovary syndrome and normal women

BACKGROUND

Inhibin B (Inh B) is produced by pre-antral and early antral follicles whereas estradiol (E(2)) is a product of follicles undergoing antrum formation. This temporal distinction is evident in the patterns of Inh B and E(2) release earlier and later during the follicular phase of the menstrual cycle, respectively. However, in previous studies of women with polycystic ovary syndrome (PCOS) and normal controls, release of these granulosa cell (GC) products appears to be simultaneous in response to FSH stimulation. In order to reconcile these disparate findings, we conducted dose-response studies in both PCOS women and normal controls to determine whether GC product responses were due to the amount of FSH administered. In addition, we compared FSH-stimulated responses in PCOS women at various stages of recovery following ovarian suppression with a long-acting GnRH agonist to examine whether Inh B and E(2) responses reflected the level of ovarian follicle activity (i.e. circulating E(2) levels).

METHODS

Women with PCOS, 18-35 years (n = 23), and normal ovulatory controls, 18-35 years (n = 10) were recruited for study. Dose-responses were assessed over 24 h following intravenous administration of 0 (saline), 37.5, 75 and 150 IU of recombinant human FSH (r-hFSH) in PCOS and normal women. In addition, E(2) and Inh B responses to 150 IU of r-hFSH were assessed at baseline and 4, 6 and 8 weeks following suppression of ovarian steroidogenesis by a long-acting GnRH agonist in PCOS women.

RESULTS

In PCOS women and normal controls, serum Inh B and E(2) exhibit similar and simultaneous dose-responsiveness to FSH stimulation. During recovery from ovarian suppression, basal and stimulated Inh B release appear to be restored earlier than that of E(2) in PCOS women.

CONCLUSIONS

These findings are consistent with the notion that, in PCOS women, the level of ovarian follicle activity largely determines the earlier release of Inh B compared with E(2).

Modulation of gonadotropin-releasing hormone pulse generator sensitivity to progesterone inhibition in hyperandrogenic adolescent girls--implications for regulation of pubertal maturation

CONTEXT

Adult women with polycystic ovary syndrome (PCOS) have decreased GnRH pulse generator sensitivity to progesterone (P)-mediated slowing. This defect is androgen mediated because it is reversed with androgen receptor blockade. Adolescent hyperandrogenism often precedes PCOS.

OBJECTIVE

The aim of the study was to evaluate GnRH pulse generator sensitivity to P-mediated slowing in normal and hyperandrogenic girls.

DESIGN

We conducted a controlled interventional study.

SETTING

The study was conducted in a general clinical research center.

PARTICIPANTS

A total of 26 normal control (NC) and 26 hyperandrogenic (HA) girls were studied.

INTERVENTION

Frequent blood sampling was performed for 11 h to assess LH pulse frequency before and after 7 d of oral estradiol and P.

MAIN OUTCOME MEASURE

We measured the slope of the percentage reduction in LH pulse frequency as a function of d 7 P (slope).

RESULTS

Overall, Tanner 3-5 HA subjects were less sensitive to P-mediated slowing than Tanner 3-5 NC (slope, 4.7 +/- 3.4 vs. 10.3 +/- 7.7; P = 0.006). However, there was variability in the responses of HA subjects; 15 had P sensitivities within the range seen in NC, whereas nine were relatively P insensitive. The two groups had similar testosterone levels. Fasting insulin levels were higher in P-insensitive HA girls (39.6 +/- 30.6 vs. 22.2 +/- 13.9 microIU/ml; P = 0.02), and there was an inverse relationship between fasting insulin and P sensitivity in HA girls (P = 0.02). Tanner 1-2 NC had lower testosterone levels and were more P sensitive than Tanner 3-5 NC (slope, 19.3 +/- 5.8; P = 0.04).

CONCLUSIONS

Hyperandrogenism is variably associated with reduced GnRH pulse generator sensitivity to P-mediated slowing during adolescence. In addition to androgen levels, insulin resistance may modulate P sensitivity.

Metabolic and hormonal changes induced by pioglitazone in polycystic ovary syndrome: a randomized, placebo-controlled clinical trial

CONTEXT

Polycystic ovary syndrome (PCOS) is characterized by insulin resistance, compensatory hyperinsulinemia, increased prevalence of impaired glucose tolerance, and increased ovarian androgen biosynthesis.

OBJECTIVE

The aim of the study was to evaluate effects of pioglitazone on whole body insulin action and ovarian androgen biosynthesis in PCOS.

DESIGN

We performed a randomized placebo-controlled trial.

SETTING

The study was conducted at the Special Diagnostic and Treatment Unit of the Veterans Affairs Medical Center, San Diego, and the University of California, San Diego, General Clinical Research Center.

PATIENTS OR OTHER PARTICIPANTS

A total of 23 subjects with PCOS were evaluated at baseline and end of treatment. Six age- and body mass index-matched women without PCOS were normal controls for baseline evaluation.

INTERVENTION

Subjects with PCOS were randomized to oral placebo or pioglitazone 45 mg daily for 6 months.

MAIN OUTCOME MEASURE(S)

The primary outcome measures were whole body insulin action as measured by hyperinsulinemic euglycemic clamp and ovarian androgen biosynthesis as measured by leuprolide-stimulated production of 17-hydroxyprogesterone (17-OHP).

RESULTS

Compared with placebo, pioglitazone treatment significantly improved multiple measures of insulin action, including glucose disposal rate (P < 0.01), 2-h glucose during 75-g oral glucose tolerance test (P < 0.01), area under the curve glucose during oral glucose tolerance test (P < 0.01), serum adiponectin (P < 0.01), and fasting hyperinsulinemia (P < 0.01). Compared to placebo, pioglitazone treatment reduced the increment of leuprolide-stimulated 17-OHP (P < 0.02). Improvements in glucose disposal rate correlated with reductions in 17-OHP stimulation (P < 0.02).

CONCLUSIONS

Compared to placebo, pioglitazone treatment in PCOS was associated with improvements in insulin action and glucose homeostasis and ameliorated the hyperandrogenic ovarian response.

Polycystic ovary syndrome is associated with tissue-specific differences in insulin resistance

OBJECTIVE

The potential differential contributions of skeletal muscle and adipose tissue to whole body insulin resistance were evaluated in subjects with polycystic ovary syndrome (PCOS).

RESEARCH DESIGN AND METHODS

Forty-two PCOS subjects and 15 body mass index-matched control subjects were studied. Insulin action was evaluated by the hyperinsulinemic/euglycemic clamp procedure. Isolated adipocytes and cultured muscle cells were analyzed for glucose transport activity; adipocytes, muscle tissue, and myotubes were analyzed for the expression and phosphorylation of insulin-signaling proteins.

RESULTS

Fifty-seven per cent of the PCOS subjects had impaired glucose tolerance and the lowest rate of maximal insulin-stimulated whole body glucose disposal compared to controls (P < 0.01). PCOS subjects with normal glucose tolerance had intermediate reduction in glucose disposal rate (P < 0.05 vs. both control and impaired glucose tolerance subjects). However, rates of maximal insulin-stimulated glucose transport (insulin responsiveness) into isolated adipocytes were comparable between all three groups, whereas PCOS subjects displayed impaired insulin sensitivity. In contrast, myotubes from PCOS subjects displayed reduced insulin responsiveness for glucose uptake and normal sensitivity. There were no differences between groups in the expression of glucose transporter 4 or insulin-signaling proteins or maximal insulin stimulation of phosphorylation of Akt in skeletal muscle, myotubes, or adipocytes.

CONCLUSIONS

Individuals with PCOS display impaired insulin responsiveness in skeletal muscle and myotubes, whereas isolated adipocytes display impaired insulin sensitivity but normal responsiveness. Skeletal muscle and adipose tissue contribute differently to insulin resistance in PCOS. Insulin resistance in PCOS cannot be accounted for by differences in the expression of selected signaling molecules or maximal phosphorylation of Akt.

Evidence for insulin suppression of baseline luteinizing hormone in women with polycystic ovarian syndrome and normal women

CONTEXT

In women with polycystic ovarian syndrome (PCOS), the relationship of insulin to LH secretion and responses to GnRH remains unresolved. A rigorous analytical examination of this relationship has not been performed.

OBJECTIVE

Our objective was to determine the relationship of basal LH secretion and responses to GnRH, insulin, and other endocrine variables in normal and PCOS women.

DESIGN

In PCOS and normal women, mean composite 12-h LH secretion was analyzed for correlating factors. LH responses to varying doses of GnRH during a fixed rate of insulin infusion and LH responses to a fixed dose of GnRH during varying doses of insulin infusion were analyzed for contributing factors.

PATIENTS AND SETTING

Eighteen PCOS and 21 normal women underwent studies of frequent blood sampling and GnRH stimulation before and during insulin infusion at the General Clinical Research Center, University of California, San Diego.

MAIN OUTCOME MEASURES

Group mean composite 12-h LH levels were assessed with respect to other endocrine variables. In addition, LH responses to GnRH with or without insulin infusion were assessed.

RESULTS

In normal women, insulin negatively predicted mean LH. In PCOS, the combined effect of body mass index (negative) and testosterone (positive) predicted LH. The best predictor of LH was body mass index and insulin combined. Basal LH and LH responses to GnRH were unaltered by insulin infusion in normal women. These measures were reduced during insulin infusion in PCOS women.

CONCLUSIONS

In PCOS, insulin infusion suppresses pituitary response to GnRH. In normal women, insulin negatively correlates with mean LH and suppresses GnRH response at a high infusion rate.

Increased androgen response to follicle-stimulating hormone administration in women with polycystic ovary syndrome

CONTEXT

In women with polycystic ovary syndrome (PCOS), excess ovarian androgen production is driven by increased LH secretion. Studies conducted in animals suggest that the granulosa cell may influence LH-stimulated theca cell androgen production.

OBJECTIVE

The objective of this study was to determine whether FSH enhances androgen production in women with PCOS compared with that of normal women.

DESIGN

A prospective study was conducted to compare androgen production in response to FSH in two groups of women.

SETTING

The study was conducted in a General Clinical Research Center in a tertiary academic medical center.

PATIENTS

Women with PCOS, 18-35 yr (n = 20), and normal ovulatory controls, 18-35 yr (n = 10), were recruited for study.

INTERVENTIONS

Serial blood samples were obtained over a 24-h period after an iv injection of recombinant human FSH (150 IU).

MAIN OUTCOME MEASURES

The main outcome measures were serum 17-hydroxyprogesterone (17-OHP), androstenedione (A), dehydroepiandrosterone (DHEA), testosterone (T), and inhibin B (Inh B) responses after FSH administration.

RESULTS

Basal serum 17-OHP, A, and T levels were markedly increased in women with PCOS compared with that observed in normal women. Basal DHEA and Inh B levels were similar to those of normal controls. After FSH injection, PCOS women demonstrated enhanced production of 17-OHP, A, DHEA, and Inh B, whereas in normal women no increases were observed. T levels declined slightly in both groups.

CONCLUSIONS

These findings provide evidence that, in PCOS women, theca cell androgen production is enhanced by FSH administration and suggest a granulosa-theca cell paracrine mechanism.

Evaluation and treatment of hirsutism in premenopausal women: an endocrine society clinical practice guideline

OBJECTIVE

Our objective was to develop clinical practice guidelines for the evaluation and treatment of hirsutism in premenopausal women.

PARTICIPANTS

The Task Force was composed of a chair, selected by the Clinical Guidelines Subcommittee (CGS) of The Endocrine Society, six additional experts, two methodologists, and a medical writer. The Task Force received no corporate funding or remuneration.

EVIDENCE

Systematic reviews of available evidence were used to formulate the key treatment and prevention recommendations. We used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) group criteria to describe both the quality of evidence and the strength of recommendations. We used "recommend" for strong recommendations, and "suggest" for weak recommendations.

CONSENSUS PROCESS

Consensus was guided by systematic reviews of evidence and discussions during one group meeting, several conference calls, and e-mail communications. The drafts prepared by the Task Force with the help of a medical writer were reviewed successively by The Endocrine Society's CGS, Clinical Affairs Core Committee (CACC), and Council. The version approved by the CGS and CACC was placed on The Endocrine Society's Web site for comments by members. At each stage of review, the Task Force received written comments and incorporated needed changes.

CONCLUSIONS

We suggest testing for elevated androgen levels in women with moderate or severe hirsutism or hirsutism of any degree when it is sudden in onset, rapidly progressive, or associated with other abnormalities such as menstrual dysfunction, obesity, or clitoromegaly. For women with patient-important hirsutism despite cosmetic measures, we suggest either pharmacological therapy or direct hair removal methods. For pharmacological therapy, we suggest oral contraceptives for the majority of women, adding an antiandrogen after 6 months if the response is suboptimal. We recommend against antiandrogen monotherapy unless adequate contraception is used. We suggest against using insulin-lowering drugs. For women who choose hair removal therapy, we suggest laser/photoepilation.

The reproductive phenotype in polycystic ovary syndrome

The symptoms of women with polycystic ovary syndrome (PCOS) include hirsutism and irregular menstrual bleeding due to ovarian androgen excess and chronic anovulation. Typically, these features emerge late in puberty or shortly thereafter. The proposed mechanism(s) responsible for increased ovarian androgen production include heightened theca cell responsiveness to gonadotropin stimulation, increased pituitary secretion of luteinizing hormone, and hyperinsulinemia. The cause of ovulatory dysfunction is not well understood, but is linked to abnormal follicle growth and development within the ovary. As a result, infertility is common among women with PCOS and, in many instances, is the initial presenting complaint. Insulin resistance and obesity are frequently associated with PCOS and probably contribute to the severity of symptoms. The polycystic ovary that accompanies the syndrome has recently been defined as having 12 or more follicles per ovary or an ovarian volume greater than 10 ml as determined by ultrasonography. In addition, there is an increased number of growing follicles in the polycystic ovary. Despite this distinctive appearance, the cause and development of the polycystic ovary are completely unknown.

Circulating and cellular adiponectin in polycystic ovary syndrome: relationship to glucose tolerance and insulin action

OBJECTIVE

To evaluate serum adiponectin levels and organization into multimers in women with polycystic ovary syndrome (PCOS) and assess relationships between adiponectin, glucose tolerance, and insulin resistance.

DESIGN

In vivo and in vitro study.

SETTING

Outpatient clinic at university and Veterans hospitals in the United States and university laboratory.

PATIENT(S)

Thirty-one obese women with PCOS and six age- and body mass index (BMI)-matched normal cycling control subjects.

INTERVENTION(S)

All subjects studied in the fasting state.

MAIN OUTCOME MEASURE(S)

A 75-g oral glucose tolerance test (OGTT), hyperinsulinemic/euglycemic clamp, circulating adiponectin levels, adipocyte adiponectin content, and organization of adiponectin into multimeric forms.

RESULT(S)

Whole body insulin action (glucose disposal rate, 5.61 +/- 2.90 vs. 8.79 +/- 0.81 mg/kg/min, PCOS and control) and adiponectin levels (9.5 +/- 0.7 7 vs. 17.4 +/- 1 microg/mL, PCOS vs. control) were significantly reduced in the subjects with PCOS. There were significant correlations between glucose tolerance, insulin action, and circulating adiponectin levels in all subjects. The content of adiponectin protein was reduced in subcutaneous adipocytes from subjects with PCOS (252 +/- 31 vs. 388 +/- 58 arbitrary units/10 microg protein). Subjects with PCOS had less of their circulating adiponectin organized into high molecular weight (HMW) multimeric complexes. Glucose-intolerant subjects with PCOS also had less intracellular HMW adiponectin.

CONCLUSION(S)

Both circulating adiponectin levels and the portion present as the most active HMW form are reduced in PCOS, with differences related to the degree of glucose intolerance and insulin resistance.

Serum anti-mullerian hormone concentrations are not altered by acute administration of follicle stimulating hormone in polycystic ovary syndrome and normal women

CONTEXT

In the human ovary, expression of anti-Mullerian hormone (AMH) is detected primarily in granulosa cells of preantral and small antral follicles. This finding is consistent with the tight correlation between circulating AMH levels and the number of small antral follicles (2-5 mm) in normal and polycystic ovary syndrome (PCOS) women. In addition, the greater follicle count in PCOS is mirrored by significantly higher serum AMH levels compared with those of normal women. Despite the utility of AMH measurements in evaluating ovarian physiology and function, the regulation of AMH remains poorly understood.

OBJECTIVE

The objective was to determine whether gonadotropins acutely regulate serum AMH in women with PCOS and normal women.

DESIGN

We conducted a prospective study to compare ovarian responses to FSH in two groups of women.

SETTING

The study was conducted in a General Clinical Research Center in a tertiary academic medical center.

PATIENTS

Women with PCOS (age, 18-35 yr; n = 16) and normal ovulatory controls (age, 18-35 yr; n = 11) were recruited for study.

INTERVENTIONS

Serum samples were measured over a 24-h period after an iv injection of recombinant human FSH (150 IU).

MAIN OUTCOME MEASURE(S)

Serum AMH responses after FSH administration were measured.

RESULTS

Basal serum AMH levels were markedly increased in women with PCOS compared with levels observed in normal women. After FSH injection, PCOS women failed to demonstrate changes in circulating AMH over 24 h. A similar lack of alteration in serum AMH was observed in normal women.

CONCLUSIONS

These findings suggest that in PCOS and normal women, acute exposure to FSH does not appear to exert an effect on AMH production.