Hypogonadotropic hypogonadism is defined as a deficiency of the pituitary secretion of follicle-stimulating hormone and luteinizing hormone, which results in the impairment of pubertal maturation and of reproductive function. In the absence of pituitary or hypothalamic anatomical lesions and of anosmia (Kallmann syndrome), hypogonadotropic hypogonadism is referred to as isolated hypogonadotropic hypogonadism (IHH). A limited number of IHH cases are due to loss-of-function mutations of the gonadotropin-releasing hormone receptor. To identify additional gene defects leading to IHH, a large consanguineous family with five affected siblings and with a normal gonadotropin-releasing hormone receptor coding sequence was studied. Homozygosity whole-genome mapping allowed the localization of a new locus within the short arm of chromosome 19 (19p13). Sequencing of several genes localized within this region showed that all affected siblings of the family carried a homozygous deletion of 155 nucleotides in the GPR54 gene. This deletion encompassed the splicing acceptor site of intron 4-exon 5 junction and part of exon 5. The deletion was absent or present on only one allele in unaffected family members. GPR54 has been initially identified as an orphan G protein-coupled receptor with 40% homology to galanin receptors. Recently, a 54-aa peptide derived from the KiSS1 protein was identified as a ligand of GPR54. The present study shows that loss of function of GPR54 is a cause of IHH, and it identifies GPR54 and possibly KiSS1 protein-derived peptide as playing a major and previously unsuspected role in the physiology of the gonadotropic axis.

METHODS

Mutations in the estrogen-receptor gene have been thought to be lethal. A 28-year-old man whose estrogen resistance was caused by a disruptive mutation in the estrogen-receptor gene underwent studies of pituitary-gonadal function and bone density and received transdermal estrogen for six months. Estrogen-receptor DNA, extracted from lymphocytes, was evaluated by analysis of single-strand-conformation polymorphisms and by direct sequencing.

RESULTS

The patient was tall (204 cm [80.3 in.]) and had incomplete epiphyseal closure, with a history of continued linear growth into adulthood despite otherwise normal pubertal development. He was normally masculinized and had bilateral axillary acanthosis nigricans. Serum estradiol and estrone concentrations were elevated, and serum testosterone concentrations were normal. Serum follicle-stimulating hormone and luteinizing hormone concentrations were increased. Glucose tolerance was impaired, and hyperinsulinemia was present. The bone mineral density of the lumbar spine was 0.745 g per square centimeter, 3.1 SD below the mean for age-matched normal women; there was biochemical evidence of increased bone turnover. The patient had no detectable response to estrogen administration, despite a 10-fold increase in the serum free estradiol concentration. Conformation analysis of his estrogen-receptor gene revealed a variant banding pattern in exon 2. Direct sequencing of exon 2 revealed a cytosine-to-thymine transition at codon 157 of both alleles, resulting in a premature stop codon. The patient's parents were heterozygous carriers of this mutation, and pedigree analysis revealed consanguinity.

CONCLUSIONS

Disruption of the estrogen receptor in humans need not be lethal. Estrogen is important for bone maturation and mineralization in men as well as women.

We have recently described a molecular gatekeeper of the hypothalamic-pituitary-gonadal axis with the observation that G protein-coupled receptor 54 (GPR54) is required in mice and men for the pubertal onset of pulsatile luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion to occur. In the present study, we investigate the possible central mode of action of GPR54 and kisspeptin ligand. First, we show that GPR54 transcripts are colocalized with gonadotropin-releasing hormone (GnRH) neurons in the mouse hypothalamus, suggesting that kisspeptin, the GPR54 ligand, may act directly on these neurons. Next, we show that GnRH neurons seem anatomically normal in gpr54-/- mice, and that they show projections to the median eminence, which demonstrates that the hypogonadism in gpr54-/- mice is not due to an abnormal migration of GnRH neurons (as occurs with KAL1 mutations), but that it is more likely due to a lack of GnRH release or absence of GnRH neuron stimulation. We also show that levels of kisspeptin injected i.p., which stimulate robust LH and FSH release in wild-type mice, have no effect in gpr54-/- mice, and therefore that kisspeptin acts directly and uniquely by means of GPR54 signaling for this function. Finally, we demonstrate by direct measurement, that the central administration of kisspeptin intracerebroventricularly in sheep produces a dramatic release of GnRH into the cerebrospinal fluid, with a parallel rise in serum LH, demonstrating that a key action of kisspeptin on the hypothalamo-pituitary-gonadal axis occurs directly at the level of GnRH release. The localization and GnRH release effects of kisspeptin thus define GPR54 as a major control point in the reproductive axis and suggest kisspeptin to be a neurohormonal effector.

Follicle stimulating hormone (FSH) is a member of the glycoprotein hormone family that includes luteinzing hormone (LH), thyroid stimulating hormone, and chorionic gonadotropin. These heterodimeric hormones share a common alpha subunit and differ in their hormone-specific beta subunit. The biological activity is conferred only by the heterodimers. FSH and LH are synthesized in the same cells of the pituitary, the gonadotrophs. FSH receptors are localized to Sertoli cells of the testes and granulosa cells of the ovary. Minimal data has been accumulated so far involving human mutations in the FSH beta, LH beta, or the gonadotropin receptor genes. There are no known mouse strains with mutations in the FSH beta gene. To generate animal models for human diseases involving the gonadotropin signal transduction pathway, we produced mice deficient in the FSH beta subunit and therefore in FSH using ES cell technology. FSH-deficient females are infertile due to a block in folliculogenesis prior to antral follicle formation. Although FSH was predicted to be necessary for spermatogenesis and Sertoli cell growth in males, FSH-deficient males are fertile despite having small testes. Our findings have important implications for male contraceptive development in humans.

The timely secretion of gonadal sex steroids is essential for the initiation of puberty, the postpubertal maintenance of secondary sexual characteristics and the normal perinatal development of male external genitalia. Normal gonadal steroid production requires the actions of the pituitary-derived gonadotropins, luteinizing hormone and follicle-stimulating hormone. We report four human pedigrees with severe congenital gonadotropin deficiency and pubertal failure in which all affected individuals are homozygous for loss-of-function mutations in TAC3 (encoding Neurokinin B) or its receptor TACR3 (encoding NK3R). Neurokinin B, a member of the substance P-related tachykinin family, is known to be highly expressed in hypothalamic neurons that also express kisspeptin, a recently identified regulator of gonadotropin-releasing hormone secretion. These findings implicate Neurokinin B as a critical central regulator of human gonadal function and suggest new approaches to the pharmacological control of human reproduction and sex hormone-related diseases.

THE D-type cyclins (D1, D2 and D3) are critical governors of the cell-cycle clock apparatus during the G1 phase of the mammalian cell cycle. These three D-type cyclins are expressed in overlapping, apparently redundant fashion in the proliferating tissues. To investigate why mammalian cells need three distinct D-type cyclins, we have generated mice bearing a disrupted cyclin D2 gene by using gene targeting in embryonic stem cells. Cyclin D2-deficient females are sterile owing to the inability of ovarian granulosa cells to proliferate normally in response to follicle-stimulating hormone (FSH), whereas mutant males display hypoplastic testes. In ovarian granulosa cells, cyclin D2 is specifically induced by FSH via a cyclic-AMP-dependent pathway, indicating that expression of the various D-type cyclins is under control of distinct intracellular signalling pathways. The hypoplasia seen in cyclin D2(-/-) ovaries and testes prompted us to examine human cancers deriving from corresponding tissues. We find that some human ovarian and testicular tumours contain high levels of cyclin D2 messenger RNA.

The established function of thyroid stimulating hormone (TSH) is to promote thyroid follicle development and hormone secretion. The osteoporosis associated with hyperthyroidism is traditionally viewed as a secondary consequence of altered thyroid function. We provide evidence for direct effects of TSH on both components of skeletal remodeling, osteoblastic bone formation, and osteoclastic bone resorption, mediated via the TSH receptor (TSHR) found on osteoblast and osteoclast precursors. Even a 50% reduction in TSHR expression produces profound osteoporosis (bone loss) together with focal osteosclerosis (localized bone formation). TSH inhibits osteoclast formation and survival by attenuating JNK/c-jun and NFkappaB signaling triggered in response to RANK-L and TNFalpha. TSH also inhibits osteoblast differentiation and type 1 collagen expression in a Runx-2- and osterix-independent manner by downregulating Wnt (LRP-5) and VEGF (Flk) signaling. These studies define a role for TSH as a single molecular switch in the independent control of both bone formation and resorption.

OBJECTIVE

This study assessed longitudinal changes in body composition, fat distribution and energy balance in perimenopausal women. We hypothesized that total fat and abdominal body fat would increase at menopause due to decreased energy expenditure (EE) and declining estrogen, respectively.

METHODS

Observational, longitudinal study with annual measurements for 4 years.

METHODS

Healthy women (103 Caucasian; 53 African-American), initially premenopausal. During follow-up, lack of menstruation for 1 year and follicle-stimulating hormone >30 mIU ml(-1) defined a subject as postmenopausal.

METHODS

Fat and lean mass (dual-energy X-ray absorptiometry), visceral (VAT) and subcutaneous abdominal fat (SAT) (computed tomography), dietary intake (4-day food record), serum sex hormones and physical activity (tri-axial accelerometry). Twenty-four hour EE was measured by whole-room calorimeter in a subset of 34 women at baseline and at year 4.

RESULTS

Body fat and weight increased significantly over time only in those women who became postmenopausal by year 4 (n=51). All women gained SAT over time; however, only those who became postmenopausal had a significant increase in VAT. The postmenopausal group also exhibited a significant decrease in serum estradiol. Physical activity decreased significantly 2 years before menopause and remained low. Dietary energy, protein, carbohydrate and fiber intake were significantly higher 3-4 years before the onset of menopause compared with menopause onset. Twenty-four hour EE and sleeping EE decreased significantly with age; however, the decrease in sleeping EE was 1.5-fold greater in women who became postmenopausal compared with premenopausal controls (-7.9 vs -5.3%). Fat oxidation decreased by 32% in women who became postmenopausal (P<0.05), but did not change in those who remained premenopausal.

CONCLUSIONS

Middle-aged women gained SAT with age, whereas menopause per se was associated with an increase in total body fat and VAT. Menopause onset is associated with decreased EE and fat oxidation that can predispose to obesity if lifestyle changes are not made.

The formation of estrogens from C19 steroids is catalyzed by aromatase cytochrome P450 (P450arom), the product of the cyp19 gene. The actions of estrogen include dimorphic anatomical, functional, and behavioral effects on the development of both males and females, considerations that prompted us to examine the consequences of deficiency of aromatase activity in mice. Mice lacking a functional aromatase enzyme (ArKO) were generated by targeted disruption of the cyp19 gene. Male and female ArKO mice were born with the expected Mendelian frequency from F1 parents and grew to adulthood. Female ArKO mice at 9 weeks of age displayed underdeveloped external genitalia and uteri. Ovaries contained numerous follicles with abundant granulosa cells and evidence of antrum formation that appeared arrested before ovulation. No corpora lutea were present. Additionally the stroma were hyperplastic with structures that appeared to be atretic follicles. Development of the mammary glands approximated that of a prepubertal female. Examination of male ArKO mice of the same age revealed essentially normal internal anatomy but with enlargement of the male accessory sex glands because of increased content of secreted material. The testes appeared normal. Male ArKO mice are capable of breeding and produce litters of approximately average size. Whereas serum estradiol levels were at the limit of detection, testosterone levels were elevated, as were the levels of follicle-stimulating hormone and luteinizing hormone. The phenotype of these animals differs markedly from that of the previously reported ERKO mice, in which the estrogen receptor alpha is deleted by targeted disruption.

Pituitary gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone stimulate the gonads by regulating germ cell proliferation and differentiation. FSH receptors (FSH-Rs) are localized to testicular Sertoli cells and ovarian granulosa cells and are coupled to activation of the adenylyl cyclase and other signaling pathways. Activation of FSH-Rs is considered essential for folliculogenesis in the female and spermatogenesis in the male. We have generated mice lacking FSH-R by homologous recombination. FSH-R-deficient males are fertile but display small testes and partial spermatogenic failure. Thus, although FSH signaling is not essential for initiating spermatogenesis, it appears to be required for adequate viability and motility of the sperms. FSH-R-deficient females display thin uteri and small ovaries and are sterile because of a block in folliculogenesis before antral follicle formation. Although the expression of marker genes is only moderately altered in FSH-R -/- mice, drastic sex-specific changes are observed in the levels of various hormones. The anterior lobe of the pituitary gland in females is enlarged and reveals a larger number of FSH- and thyroid-stimulating hormone (TSH)-positive cells. The phenotype of FSH-R -/- mice is reminiscent of human hypergonadotropic ovarian dysgenesis and infertility.

The genetic loci agouti and extension control the relative amounts of eumelanin (brown-black) and phaeomelanin (yellow-red) pigments in mammals: extension encodes the receptor for melanocyte-stimulating hormone (MSH) and agouti encodes a novel 131-amino-acid protein containing a signal sequence. Agouti, which is produced in the hair follicle, acts on follicular melanocytes to inhibit alpha-MSH-induced eumelanin production, resulting in the subterminal band of phaeomelanin often visible in mammalian fur. Here we use partially purified agouti protein to demonstrate that agouti is a high-affinity antagonist of the MSH receptor and blocks alpha-MSH stimulation of adenylyl cyclase, the effector through which alpha-MSH induces eumelanin synthesis. Agouti was also found to be an antagonist of the melanocortin-4 receptor, a related MSH-binding receptor. Consequently, the obesity caused by ectopic expression of agouti in the lethal yellow (Ay) mouse may be due to the inhibition of melanocortin receptor(s) outside the hair follicle.

The G protein-coupled receptor GPR54 (AXOR12, OT7T175) is central to acquisition of reproductive competency in mammals. Peptide ligands (kisspeptins) for this receptor are encoded by the Kiss1 gene, and administration of exogenous kisspeptins stimulates hypothalamic gonadotropin-releasing hormone (GnRH) release in several species, including humans. To establish that kisspeptins are the authentic agonists of GPR54 in vivo and to determine whether these ligands have additional physiological functions we have generated mice with a targeted disruption of the Kiss1 gene. Kiss1-null mice are viable and healthy with no apparent abnormalities but fail to undergo sexual maturation. Mutant female mice do not progress through the estrous cycle, have thread-like uteri and small ovaries, and do not produce mature Graffian follicles. Mutant males have small testes, and spermatogenesis arrests mainly at the early haploid spermatid stage. Both sexes have low circulating gonadotropin (luteinizing hormone and follicle-stimulating hormone) and sex steroid (beta-estradiol or testosterone) hormone levels. Migration of GnRH neurons into the hypothalamus appears normal with appropriate axonal connections to the median eminence and total GnRH content. The hypothalamic-pituitary axis is functional in these mice as shown by robust luteinizing hormone secretion after peripheral administration of kisspeptin. The virtually identical phenotype of Gpr54- and Kiss1-null mice provides direct proof that kisspeptins are the true physiological ligand for the GPR54 receptor in vivo. Kiss1 also does not seem to play a vital role in any other physiological processes other than activation of the hypothalamic-pituitary-gonadal axis, and loss of Kiss1 cannot be overcome by compensatory mechanisms.

Changes of bone turnover with aging are responsible for bone loss and play a major role in osteoporosis. Although an increase of bone turnover has been documented at the time of menopause, the subsequent abnormalities of bone resorption and formation and their potential role in determining bone mass in the elderly have not been investigated. To address this issue, we have measured a battery of new sensitive and specific markers of bone turnover in a population-based study of 653 healthy women analyzed cross-sectionally, including 432 women postmenopausal from 1 to 40 years, and the data were correlated with bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) at different skeletal sites. Bone formation was assessed by serum osteocalcin (OC), serum bone-specific alkaline phosphatase (B-ALP), serum C-propeptide of type I collagen (PICP), and bone resorption by the urinary excretion of two pyridinoline cross-linked peptides (NTX and CTX). Bone turnover increased in perimenopausal women with both irregular menses and elevated serum follicle stimulating hormone (FSH). Menopause induced a 37-52% and 79-97% increase in the bone formation and bone resorption marker levels, respectively (p < 0.0001 except for PICP). In postmenopausal women, bone formation markers did not decrease with age. When resorption markers were corrected by whole body bone mineral content (BMC), the fraction of bone resorbed per day was not correlated with age in postmenopausal women and remained elevated for up to 40 years after menopause. In premenopausal women, the bone turnover rate accounted for only 0-10% of the variation in whole body BMC, total hip, distal radius, and lumbar spine BMD. With increasing time after menopause, the importance of the bone turnover rate as a determinant of bone mass increased at all sites and accounted for up to 52% of the BMD variance in elderly women. Thus, in women 20 years or more postmenopause, bone turnover was higher in those in the lowest quartile than in those in the highest quartile of BMD. In elderly women, 20 years since menopause and over, but not in younger ones, serum PTH was negatively correlated with serum 25-hydroxyvitamin D (r = -0.22, p < 0.05) and explained only 5-8% of the bone turnover variance (p < 0.01-0.001). These data indicate that the overall rates of both bone formation and bone resorption remain high in elderly women. The rate of bone turnover appears to play an increasing role as a determinant of bone mass with increasing time since menopause with a high bone turnover rate being associated with a low bone mass. Thus assessing bone marker levels may be useful in the evaluation of osteoporosis risk. In elderly women, secondary hyperparathyroidism caused in part by reduced serum 25-hydroxyvitamin D appears to be a marginal determinant of an increased bone turnover rate.

Follicle-stimulating hormone (FSH) is central to reproduction in mammals. It acts through a G-protein-coupled receptor on the surface of target cells to stimulate testicular and ovarian functions. We present here the 2.9-A-resolution structure of a partially deglycosylated complex of human FSH bound to the extracellular hormone-binding domain of its receptor (FSHR(HB)). The hormone is bound in a hand-clasp fashion to an elongated, curved receptor. The buried interface of the complex is large (2,600 A2) and has a high charge density. Our analysis suggests that all glycoprotein hormones bind to their receptors in this mode and that binding specificity is mediated by key interaction sites involving both the common alpha- and hormone-specific beta-subunits. On binding, FSH undergoes a concerted conformational change that affects protruding loops implicated in receptor activation. The FSH-FSHR(HB) complexes form dimers in the crystal and at high concentrations in solution. Such dimers may participate in transmembrane signal transduction.

G-protein-coupled receptors (GPCRs) are generally thought to signal to second messengers like cyclic AMP (cAMP) from the cell surface and to become internalized upon repeated or prolonged stimulation. Once internalized, they are supposed to stop signaling to second messengers but may trigger nonclassical signals such as mitogen-activated protein kinase (MAPK) activation. Here, we show that a GPCR continues to stimulate cAMP production in a sustained manner after internalization. We generated transgenic mice with ubiquitous expression of a fluorescent sensor for cAMP and studied cAMP responses to thyroid-stimulating hormone (TSH) in native, 3-D thyroid follicles isolated from these mice. TSH stimulation caused internalization of the TSH receptors into a pre-Golgi compartment in close association with G-protein alpha(s)-subunits and adenylyl cyclase III. Receptors internalized together with TSH and produced downstream cellular responses that were distinct from those triggered by cell surface receptors. These data suggest that classical paradigms of GPCR signaling may need revision, as they indicate that cAMP signaling by GPCRs may occur both at the cell surface and from intracellular sites, but with different consequences for the cell.

Using QCT, we made a longitudinal, population-based assessment of rates of bone loss over life at the distal radius, distal tibia, and lumbar spine. Cortical bone loss began in perimenopause in women and later in life in men. In contrast, trabecular bone loss began in young adulthood in both sexes.

BACKGROUND

Although conventional wisdom holds that bone loss begins at menopause in women and later in life in men, this has not been examined longitudinally in population-based studies using precise technology capable of distinguishing cortical and trabecular bone.

METHODS

In an age- and sex-stratified population sample (n = 553), we measured volumetric BMD (vBMD) of trabecular and cortical bone by QCT annually for up to 3 yr at the distal radius (DR) and distal tibia (DT) (n = 552) and trabecular vBMD at baseline and 3 yr at the lumbar spine (LS) (n = 474).

RESULTS

Substantial cortical bone loss began in middle life in women but began mainly after age 75 in men. In contrast, substantial trabecular bone loss began in young adult women and men at all three skeletal sites and continued throughout life with acceleration during perimenopause in women. Women experienced 37% and men experienced 42% of their total lifetime trabecular bone loss before age 50 compared with 6% and 15%, respectively, for cortical bone. Median rates of change in trabecular bone (%/yr) were -0.40, -0.24, and -1.61 in young adult women and -0.38, -0.40, and -0.84 in young adult men at the DR, DT, and LS, respectively (all p < 0.001). The early trabecular bone loss did not consistently correlate with putative causal factors, except for a trend with IGF-related variables at DT in women. However, in postmenopausal women and, to a lesser extent, in older men, higher rates of cortical and trabecular bone loss were associated with lower levels of biologically-active sex steroids and with higher levels of follicle-stimulating hormone and bone turnover markers.

CONCLUSIONS

The late onset of cortical bone loss is temporally associated with sex steroid deficiency. However, the early-onset, substantial trabecular bone loss in both sexes during sex steroid sufficiency is unexplained and indicates that current paradigms on the pathogenesis of osteoporosis are incomplete.

BACKGROUND

Whether depressed mood reported in the transition to menopause by women with no history of depression is associated with menopausal status and changes in reproductive hormones is controversial and lacks scientific information.

OBJECTIVE

To identify new onset of depressive symptoms and diagnosed depressive disorders in the menopausal transition and to determine the associations of menopausal status, reproductive hormones, and other risk factors with these cases.

METHODS

A within-woman, longitudinal (8-year) study to identify risk factors of depressed mood.

METHODS

A subset of a randomly identified, population-based cohort.

METHODS

Premenopausal women with no history of depression at cohort enrollment.

METHODS

The Center for Epidemiological Studies of Depression scale (CES-D) was used to assess depressive symptoms, and the Primary Care Evaluation of Mental Disorders (PRIME-MD) was used to identify clinical diagnoses of depressive disorders.

RESULTS

High CES-D scores >> or=16) were more than 4 times more likely to occur during a woman's menopausal transition compared with when she was premenopausal (odds ratio, 4.29; 95% confidence interval, 2.39-7.72; P<.001). Within-woman change in menopausal status, increased levels of follicle-stimulating hormone and luteinizing hormone, and increased variability of estradiol, follicle-stimulating hormone, and luteinizing hormone around the woman's own mean levels were each significantly associated with high CES-D scores after adjusting for smoking, body mass index, premenstrual syndrome, hot flashes, poor sleep, health status, employment, and marital status. A diagnosis of depressive disorder was 2(1/2) times more likely to occur in the menopausal transition compared with when the woman was premenopausal (odds ratio, 2.50; 95% confidence interval, 1.25-5.02; P=.01); the hormone measures were also significantly associated with this outcome.

CONCLUSIONS

Transition to menopause and its changing hormonal milieu are strongly associated with new onset of depressed mood among women with no history of depression.

The immediate-early transcription factor NGFI-A (also called Egr-1, zif/268, or Krox-24) is thought to couple extracellular signals to changes in gene expression. Although activins and inhibins regulate follicle-stimulating hormone (FSH) synthesis, no factor has been identified that exclusively regulates luteinizing hormone (LH) synthesis. An analysis of NGFI-A-deficient mice derived from embryonic stem cells demonstrated female infertility that was secondary to LH-beta deficiency. Ovariectomy led to increased amounts of FSH-beta but not LH-beta messenger RNA, which suggested a pituitary defect. A conserved, canonical NGFI-A site in the LH-beta promoter was required for synergistic activation by NGFI-A and steroidogenic factor-1 (SF-1). NGFI-A apparently influences female reproductive capacity through its regulation of LH-beta transcription.

Hypergonadotropic ovarian dysgenesis (ODG) with normal karyotype is a heterogeneous condition that in some cases displays Mendelian recessive inheritance. By systematically searching for linkage in multiplex affected families, we mapped a locus for ODG to chromosome 2p. As the previously cloned follicle-stimulating hormone receptor (FSHR) gene had been assigned to 2p, we searched it for mutations. A C566T transition in exon 7 of FSHR predicting an Ala to Val substitution at residue 189 in the extracellular ligand-binding domain segregated perfectly with the disease phenotype. Expression of the gene in transfected cells demonstrated a dramatic reduction of binding capacity and signal transduction, but apparently normal ligand-binding affinity of the mutated receptor. We conclude that the mutation causes ODG in these families.

OBJECTIVE

To identify symptoms that change in prevalence and severity during midlife and evaluate their relationships to menopausal status, hormonal levels, and other factors.

METHODS

In a longitudinal, population-based study of 438 Australian-born women observed for 7 years with an 89% retention rate, 172 advanced from premenopause to perimenopause or postmenopause. Annual measures included a 33-item symptom check list; psychosocial, lifestyle, and health-related factors; menstrual status; hormone usage; and blood levels of follicle-stimulating hormone and estradiol (E2).

RESULTS

Increasing from early to late perimenopause were the number of women who reported five or more symptoms (+14%), hot flushes (+27%), night sweats (+17%) and vaginal dryness (+17%) (all P <.05). Breast soreness-tenderness decreased with the menopausal transition (-21%). Trouble sleeping increased by +6%. The major change in prevalence was from early to late perimenopause, except for insomnia, which showed a gradual increase. Those variables most related to onset of hot flushes were number of symptoms at early perimenopause (P <.05), having an unskilled or no occupation (P <.05), more than 10 pack-years of smoking (P <.01), and decreased E2 (P <.01). The onset of night sweats increased with the change in E2 (P <.05). The onset of vaginal dryness decreased with more years of education (P <.05). Trouble sleeping was predicted by prior lower well-being (P <.01), belief at baseline that women with many interests hardly notice menopause (P <.01), and hot flushes (P <.01).

CONCLUSIONS

Although middle-aged women are highly symptomatic, the symptoms that appear to be specifically related to hormonal changes of menopausal transition are vasomotor symptoms, vaginal dryness, and breast tenderness. Insomnia reflected bothersome hot flushes and psychosocial factors.

OBJECTIVE

The aim of this article is to summarize the recommended updates to the 2001 Stages of Reproductive Aging Workshop (STRAW) criteria. The 2011 STRAW + 10 reviewed advances in understanding of the critical changes in hypothalamic-pituitary-ovarian function that occur before and after the final menstrual period.

METHODS

Scientists from five countries and multiple disciplines evaluated data from cohort studies of midlife women and in the context of chronic illness and endocrine disorders on change in menstrual, endocrine, and ovarian markers of reproductive aging including antimüllerian hormone, inhibin-B, follicle-stimulating hormone, and antral follicle count. Modifications were adopted by consensus.

RESULTS

STRAW + 10 simplified bleeding criteria for the early and late menopausal transition, recommended modifications to criteria for the late reproductive stage (Stage -3) and the early postmenopause stage (Stage +1), provided information on the duration of the late transition (Stage -1) and early postmenopause (Stage +1), and recommended application regardless of women's age, ethnicity, body size, or lifestyle characteristics.

CONCLUSIONS

STRAW + 10 provides a more comprehensive basis for assessing reproductive aging in research and clinical contexts. Application of the STRAW + 10 staging system should improve comparability of studies of midlife women and facilitate clinical decision making. Nonetheless, important knowledge gaps persist, and seven research priorities are identified.

BACKGROUND

Circumstantial evidence links endogenous estrogens to increased risk of breast cancer in women, but direct epidemiologic support is limited. In particular, only a few small prospective studies have addressed this issue.

OBJECTIVE

Our purpose was to assess breast cancer risk in relation to circulating levels of the two major endogenous estrogens, estrone and estradiol, measured before the clinical onset of the disease.

METHODS

The association between serum levels of estrogens and the risk of breast cancer was examined in a prospective cohort study of 14,291 New York City women, 35-65 years of age, who received screening for breast cancer at the time of blood sampling and who had not been diagnosed with breast cancer. During the first 5 1/2 years of study, we identified 130 breast cancers among the postmenopausal group (7063 women, 35,509 person-years). The case subjects and twice as many postmenopausal control subjects were included in a case-control study nested within the cohort. Biochemical analyses for percent free estradiol, percent estradiol bound to sex hormone-binding globulin (SHBG), total estradiol, estrone, and follicle-stimulating hormone were performed on sera that had been kept at -80 degrees C since sampling.

RESULTS

For increasing quartiles of total estradiol, the odds ratio (ORs) of breast cancer, as adjusted for Quetelet index (weight in kilograms divided by the square of the height in meters), were 1.0, 0.9, 1.8, and 1.8 (P value for trend = .06); the ORs for increasing quartiles of estrone were 1.0, 2.2, 3.7, and 2.5 (P value for trend = .06). For increasing quartiles of free estradiol, defined as the fraction of estradiol that is not bound to proteins, the Quetelet index-adjusted ORs of breast cancer were 1.0, 1.4, 3.0, and 2.9 (P value for trend < .01). When we considered the percent of estradiol bound to SHBG, the Quetelet index-adjusted ORs were 1.0, 0.70, 0.40, and 0.32 (P value for trend < .01), thus suggesting a strong protective effect. These associations persisted or became even stronger when analyses were restricted to women whose samples had been drawn 2 or more years before breast cancer diagnosis.

CONCLUSIONS

These data represent the first confirmation in a large prospective epidemiologic study of a link between circulating estrogens and breast cancer risk. Although estrogen levels appeared to fall within the conventional limits of normality in all women under study, those who subsequently developed breast cancer tended to show higher levels of estrone, total estradiol, and free estradiol, and a lower percent of estradiol bound to SHBG than women who remained free of cancer.

CONCLUSIONS

Factors that increase endogenous estrogen production or reduce the binding of estradiol to SHBG may increase a woman's risk of developing breast cancer later in life.

Inhibin is a gonadal protein that specifically inhibits the secretion of pituitary follicle-stimulating hormone (FSH). Two forms of inhibin (A and B) have been purified from porcine follicular fluid and characterized as heterodimers of relative molecular mass (Mr) 32,000 (ref. 2). Each inhibin is comprised of an identical alpha-subunit of Mr 18,000 and a distinct but related beta-subunit of Mr 13,800-14,700 linked by interchain disulphide bond(s). Throughout the purification of inhibins, we consistently observed two fractions which stimulated the secretion of pituitary FSH. We report here the isolation of one of the FSH-releasing proteins; it has a Mr of 24,000 and its N-terminal sequences up to residue 32 are identical to those of each beta-subunit of inhibins A and B. In the presence of reducing agents, SDS-polyacrylamide gel electrophoresis resolves the FSH-releasing substance into two subunits which are identical in their migration behaviour to the reduced beta-subunits of inhibins A and B. Based on the N-terminal sequence data and Mr of the intact and reduced molecules, we propose that the FSH-releasing substance, which is active in picomolar concentrations, is a heterodimeric protein composed of the two beta-subunits of inhibins A and B linked by interchain disulphide bond(s). The structural organization of the FSH-releasing substance is homologous to that of transforming growth factor-beta (TGF-beta), which also possesses FSH-releasing activity in the same bioassay. We suggest that the substance be called activin to signify the fact that it has opposite biological effects to inhibin.