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Publication
Journal: FASEB Journal
July/16/2003
Abstract
Follicle-stimulating hormone (FSH) controls the development of follicle-enclosed oocytes in the mammalian ovary by interacting with specific receptors located exclusively on granulosa cells. Its biological activity involves stimulation of intercellular communication, intracellular signaling, and up-regulation of steroidogenesis; the entire spectrum of genes regulated by FSH is not yet fully characterized. We have established monoclonal rat FSH-responsive granulosa cell lines that express FSH receptors at 20-fold higher rates than with primary cells, and thus increased the probability of yielding a distinct spectrum of genes modulated by FSH. Using Affymetrix DNA microarrays, we discovered 11 genes not reported earlier to be up-regulated by FSH and 9 genes not reported earlier to be down-regulated by FSH. Modulation of signal transduction associated with G-protein signaling, phosphorylation of proteins, and intracellular-extracellular ion balance was suggested by up-regulation of decay accelerating factor GPI-form precursor (DAF), membrane interacting protein RGS16, protein tyrosine phosphatase (PTPase), oxidative stress-inducible protein tyrosine phosphatase (OSIPTPase), and down-regulation of rat prostatic acid phosphatase (rPAP), Na+, K+-ATPase, and protein phosphatase 1beta. Elevation in granzyme-like proteins 1 and 3, and natural killer (NK) cell protease 1 (NKP-1) along with reduction in carboxypeptidase E indicates possible FSH-mediated preparation of the cells for apoptosis. Up-regulation of vascular endothelial growth factors indicates the ability of FSH to produce angiogenic factors upon their maturation; whereas, reduction in insulin-like growth factor binding protein (IGFBP3) indicates its increased potential to promote p53-induced apoptosis. Striking similarities in FSH modulation of gene expression were found in primary cultures of human granulosa cells obtained from IVF patients although these cells expressed only 1% of FSH receptor compared with immortalized rat cells, as indicated by microarray technique, which probably is in the normal range of expression of this receptor in nontransformed cells. These findings should increase our understanding of the mechanism of FSH action in stimulating development of the ovarian follicular cells, of intracellular and intercellular communication, and of increasing the potential of ovarian follicular cells to undergo apoptosis during the process of selection of the dominant follicle.
Publication
Journal: Menopause
October/26/2009
Abstract
OBJECTIVE
To investigate the variability and determinants of menopause age in two European cohort studies, the European Respiratory Health Survey and the Swiss Air Pollution and Lung Disease in Adults Cohort.
METHODS
Age at menopause was estimated in 5,288 women, aged 30 to 60 years, randomly selected in nine European countries between 1998 and 2002. Determinants of natural and surgically induced menopause were investigated by Cox regression and heterogeneity by meta-analysis. Follicle-stimulating hormone and luteinizing hormone levels were assessed in a subsample.
RESULTS
A quarter of the women were postmenopausal by age 50.8 years. Median age of natural menopause was 54 years. Hormone levels were within expected ranges for premenopausal and postmenopausal women. Surgically induced menopause was highly prevalent (22%-47%), associated with earlier timing of menopause. Determinants of earlier menopause were current smoking (hazard ratio [HR], 1.59; 95% CI, 1.27-1.98), body mass index greater than 30 kg/m (HR, 1.32; 95%, CI, 1.02-1.70), and low physical activity (HR, 1.37; 95%, CI, 1.12-1.67). The determinant for later menopause was multiparity (HR, 0.74; 95% CI, 0.62-0.89). Predictors were similar for naturally and surgically induced menopause. Oral contraceptive use yielded heterogeneous effects on timing of menopause. Later birth was associated with later menopause (HR, 0.934; 95% CI, 0.91-0.96). This evidence of a secular trend is heterogeneous across countries.
CONCLUSIONS
Age at menopause varies across Europe, shifting toward higher ages. This secular trend seems paradoxical because several adult determinants, that is, overweight, smoking, sedentarity, and nulliparity, associated with early menopause are on the rise in Europe. The heterogeneity of the secular trend suggests additional country-specific factors not included in the study, such as improved childhood nutrition and health, that have an influence on reproductive aging.
Publication
Journal: Molecular Endocrinology
November/29/1999
Abstract
Premature ovarian failure occurs in almost 1% of women under age 40. Molecular alterations of the FSH receptor (FSHR) have recently been described. A first homozygous mutation of the FSHR was identified in Finland. More recently, we described two new mutations of the FSHR in a woman presenting a partial FSH-resistance syndrome (patient 1). We now report new molecular alterations of the FSHR in another woman (patient 2) who presented at the age of 19 with primary amenorrhea contrasting with normal pubertal development. She had high plasma FSH, and numerous ovarian follicles up to 3 mm in size were evidenced by ultrasonography. Histological and immunohistochemical examination of ovarian biopsies revealed the presence of a normal follicular development up to the antral stage and disruption at further stages. DNA sequencing showed two heterozygous mutations: Asp224Val in the extracellular domain and Leu601Val in the third extracellular loop of FSHR. Cells transfected with expression vectors encoding the wild type or the mutated Leu601Val receptors bound hormone with similar affinity, whereas binding was barely detectable with the Asp224Val mutant. Confocal microscopy showed the latter to have an impaired targeting to the cell membrane. This was confirmed by its accumulation as a mannose-rich precursor. Adenylate cyclase stimulation by FSH of the Leu601Val mutant receptor showed a 12+/-3% residual activity, whereas in patient 1 a 24+/-4% residual activity was detected for the Arg573Cys mutant receptor. These results are in keeping with the fact that estradiol and inhibin B levels were higher in patient 1 and that stimulation with recombinant FSH did not increase follicular size, estradiol, or inhibin B levels in patient 2 in contrast to what was observed for patient 1. Thus, differences in the residual activity of mutated FSHR led to differences in the clinical, biological, and histological phenotypes of the patient.
Publication
Journal: Journal of reproductive medicine, The
October/9/1996
Abstract
Depot medroxyprogesterone acetate (DMPA) is an aqueous suspension of 17-acetoxy 6-methyl progestin administered by intramuscular injection for long-term contraception. This highly effective injectable formulation of medroxyprogesterone acetate (MPA) has a prolonged duration of action since the progestin is released slowly from the muscle. MPA is detected in the serum within 30 minutes after an injection of 150 mg. Serum concentrations vary between individual women but generally plateau at about 1.0 ng/mL for about three months, after which there is a gradual decline. In some women, MPA can be detected in the serum for as long as nine months after a single injection of 150 mg. The circulating MPA initially inhibits the midcycle leutinizing hormone (LH) peak, but LH and follicle stimulating hormone (FSH) levels remain in the range of those for the luteal phase of a pretreatment control cycle. Since ovulation is inhibited, serum progesterone levels remain low (< 0.4 ng/mL) for several months following an injection of DMPA. When MPA levels fall below 0.1 ng/mL, ovulation resumes. Thus, return to fertility is delayed for several months if a woman wishes to conceive after receiving one or more injections of DMPA. Following an injection of DMPA, serum estradiol levels initially are in the early to midfollicular phase range (mean approximately 50 pg/nL). Serum estradiol levels begin to rise about four months after a single injection when MPA levels fall below 0.5 ng/mL. For women who have used DMPA for several years, serum estradiol levels range between 10 and 92 pg/mL, with mean levels of about 40 pg/mL. Despite these low levels of estradiol, hot flushes are a rare event, and the vaginal epithelium remains moist and well rugated. Women using DMPA for several years do not observe a change in breast size. DMPA causes the endometrium to become atrophic, with small, straight endometrial glands and decidualized stroma. The cervical mucus remains thick and viscid. DMPA is a very effective form of contraception because of its multiple mechanisms of action and slow release into the circulation.
Publication
Journal: American Journal of Epidemiology
March/24/1994
Abstract
Human reproductive endocrine data may be an important source of epidemiologic information in regard to the toxic potential of 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin). The association of serum dioxin with total serum testosterone, luteinizing hormone, and follicle-stimulating hormone was examined in 248 chemical production workers from New Jersey and Missouri plants and 231 nonexposed neighborhood referents who participated in a medical evaluation in 1987. In linear regression analyses, current serum dioxin was positively and significantly related to luteinizing hormone and follicle-stimulating hormone and inversely related to total testosterone after adjustment for potential confounders (p < 0.05). These trends were also apparent in logistic regression analyses, in which the authors examined the odds ratios of high luteinizing hormone >> 28 IU/liter), high follicle-stimulating hormone >> 31 IU/liter), and low testosterone (< 10.4 nmol/liter) by serum dioxin quartiles. There was a greater prevalence of high luteinizing hormone among workers in the second (odds ratio (OR) = 1.9, 95% confidence interval (CI) 0.7-5.5), third (OR = 2.5, 95% CI 0.9-7.3), and fourth (OR = 1.9, 95% CI 0.7-5.0) quartiles of serum dioxin compared with referents. For follicle-stimulating hormone, the authors observed a greater prevalence of high follicle-stimulating hormone among workers in the fourth quartile (OR = 2.0, 95% CI 0.7-5.6) compared with referents. Similarly, the prevalence of low testosterone was two to four times greater among workers in the second (OR = 3.9, 95% CI 1.3-11.3), third (OR = 2.7, 95% CI 0.9-8.2), and fourth quartiles (OR = 2.1, 95% CI 0.8-5.8) than among referents. The trends observed in these data offer human evidence of alterations in male reproductive hormone levels associated with dioxin exposure. The results support the animal literature in which dioxin-related effects have been observed on the hypothalamic-pituitary-Leydig-cell axis and on testosterone synthesis.
Publication
Journal: Archives of Gynecology and Obstetrics
June/23/2011
Abstract
BACKGROUND
The diagnosis of premature ovarian failure (POF) is based on the finding of amenorrhea before the age of 40 years associated with follicle-stimulating hormone levels in the menopausal range. It is a heterogeneous disorder affecting approximately 1% of women <40 years, 1:10,000 women by age 20 years and 1:1,000 women by age 30 years. POF is generally characterized by low levels of gonadal hormones (estrogens and inhibins) and high levels of gonadotropins (LH and FSH) (hypergonadotropic amenorrhea).
METHODS
Review of significant articles regarding genetic causes that are associated with POF.
RESULTS
Heterogeneity of POF is reflected by a variety of possible causes, including autoimmunity, toxics, drugs, as well as genetic defects. Changes at a single autosomal locus and many X-linked loci have been implicated in women with POF. X chromosome abnormalities (e.g., Turner syndrome) represent the major cause of primary amenorrhea associated with ovarian dysgenesis. Many genes have been involved in POF development, among them BMP15, FMR1, FMR2, LHR, FSHR, INHA, FOXL2, FOXO3, ERα, SF1, ERβ and CYP19A1 genes.
CONCLUSIONS
Despite the description of several candidate genes, the cause of POF remains undetermined in the vast majority of cases.
Publication
Journal: American Journal of Epidemiology
May/21/2012
Abstract
C-reactive protein (CRP) is one of the most commonly used markers of acute phase reaction in clinical settings and predictors of cardiovascular risk in healthy women; however, data on its physiologic regulation in premenopausal women are sparse. The objective of this study was to evaluate the association between endogenous reproductive hormones and CRP in the BioCycle Study (2005-2007). Women aged 18-44 years from western New York were followed prospectively for up to 2 menstrual cycles (n = 259). Serum levels of CRP, estradiol, progesterone, luteinizing hormone, and follicle-stimulating hormone were measured up to 8 times per cycle, timed by fertility monitors. CRP levels varied significantly across the cycle (P < 0.001). More women were classified as being at elevated risk of cardiovascular disease (CRP, >3 mg/L) during menses compared with other phases (12.3% vs. 7.4%; P < 0.001). A 10-fold increase in estradiol was associated with a 24.3% decrease in CRP (95% confidence interval: 19.3, 29.0). A 10-fold increase in luteal progesterone was associated with a 19.4% increase in CRP (95% confidence interval: 8.4, 31.5). These results support the hypothesis that endogenous estradiol might have antiinflammatory effects and highlight the need for standardization of CRP measurement to menstrual cycle phase in reproductive-aged women.
Publication
Journal: Obstetrics and Gynecology
July/8/2007
Abstract
OBJECTIVE
Traditionally, the most important measurement in the assessment of ovarian function has been age-independent baseline follicle-stimulating hormone (FSH) levels. The objective of this study was to characterize the continuum of ovarian function based on age-specific categories of baseline FSH.
METHODS
In a cross-sectional historical cohort study we evaluated records of 434 patients with baseline FSH levels of less than 12 milli international units/mL that underwent ovulation induction for in vitro fertilization (IVF) with long gonadotropin-releasing hormone (GnRH) antagonist or GnRH agonist suppression and modal gonadotropin stimulation of 300 units of gonadotropins per day. In these patients with apparent normal ovarian function by current baseline FSH criteria and with routine ovarian stimulation, we assessed IVF cycle outcomes, including oocyte yields, based on age-specific baseline FSH levels, defined as levels less than or equal to the 95% confidence interval for each age group.
RESULTS
Age-specific baseline FSH levels predicted the retrieval of fewer than or equal to four oocytes, with a positive predictive value of 19.5% and a negative predictive value of 88%. The Mantel-Haenszel common odds ratio for fewer than or equal to 4 oocyte production in the presence of premature ovarian aging was 2.8 (95% confidence interval 1.52-5.17; P<.001).
CONCLUSIONS
These results suggest that, within generally accepted normal baseline FSH values, women with baseline FSH above the 95% confidence limits for age produce fewer oocytes in response to normal ovulation induction protocols compared with other women their age.
Publication
Journal: Endocrinology
February/12/2003
Abstract
We recently created a novel transgenic (tg) model to examine the specific gonadal actions of FSH, distinct from LH effects, by expressing tg-FSH in gonadotropin-deficient hypogonadal (hpg) mice. Using this unique in vivo paradigm, we now describe the postnatal cellular development in seminiferous tubules selectively stimulated by tg-FSH alone or combined with testosterone (T). In the alphabeta.6 line, tg-FSH stimulated the maturation and proliferation ( approximately 2-fold) of Sertoli cells in hpg testes. Total Sertoli cell numbers were also significantly increased (1.5-fold) independently of FSH effects by T treatment alone. Selective FSH activity in alphabeta.6 hpg testes increased total spermatogonia numbers 3-fold, which established a normal spermatogonia/Sertoli cell ratio. FSH also elevated meiotic spermatocyte numbers 7-fold, notably at pachytene (28-fold), but induced only limited numbers of postmeiotic haploid cells (absent in hpg controls) that arrested during spermatid elongation. In contrast, T treatment alone had little effect on postnatal spermatogonial proliferation but greatly enhanced meiotic progression with total spermatocytes increased 12-fold (pachytene 53-fold) relative to hpg testes, and total spermatid numbers 11-fold higher than tg-FSH hpg testes. Combining tg-FSH and T treatment had no further effect on Sertoli or spermatogonia numbers relative to FSH alone but had marked additive and synergistic effects on meiotic cells, particularly pachytene (107-fold more than hpg), to establish normal meiotic germ cell/Sertoli cell ratios. Furthermore, tg-FSH had a striking synergistic effect with T treatment on total spermatid numbers (19-fold higher than FSH alone), although spermatid to Sertoli cell ratios were not fully restored to normal, indicating elevated Sertoli cell numbers alone are insufficient to establish a maximal postmeiotic germ cell capacity. This unique model has allowed a detailed dissection of FSH in vivo activity alone or with T and provided compelling evidence that FSH effects on spermatogenesis are primarily via Sertoli and spermatogonial proliferation and the stimulation of meiotic and postmeiotic germ cell development in synergy with and dependent on T actions.
Publication
Journal: Molecular Endocrinology
August/16/2010
Abstract
Activin is a major physiological regulator of FSH. We identify FoxL2 as a critical component in activin induction of FSHbeta, both for the mouse gene, induction of which is Sma- and Mad-related protein (Smad) dependent, and for the human gene that is Smad independent. FoxL2 has been shown to regulate gonadotrope gene expression (GnRH receptor, alpha-glycoprotein subunit, porcine FSHbeta, and follistatin), but the mechanisms of action are not well understood. We identify novel sites required for activin action in both the mouse and human FSHbeta promoters, some of which bind FoxL2, and show that the FoxL2-binding element encompasses a larger region (12 bp) than the previously identified forkhead-binding consensus (7 bp). Remarkably, although required for activin induction, FoxL2 sites neither contribute to basal FSHbeta promoter activity nor confer activin response to a heterologous promoter; thus, they are neither classical activin-response elements nor is their role solely to recruit Smads to the promoter. FoxL2 overexpression can potentiate activin induction in gonadotropes and can confer activin responsiveness to FSHbeta in heterologous cells where this promoter is normally refractory to activin induction. Although Smad3 requires the presence of FoxL2 sites to induce mouse FSHbeta, even through its consensus Smad-binding element; the human promoter, which is induced by activin independently of Smad3, also requires FoxL2 sites for its induction by activin; thus the actions of FoxL2 are not exclusively through interactions with the Smad pathway. Thus, FoxL2 plays a key role in activin induction of the FSHbeta gene, by binding to sites conserved across multiple species.
Publication
Journal: Endocrinology
September/21/2008
Abstract
Spermatogenesis in the adult male depends on the action of FSH and androgen. Ablation of either hormone has deleterious effects on Sertoli cell function and the progression of germ cells through spermatogenesis. In this study we generated mice lacking both FSH receptors (FSHRKO) and androgen receptors on the Sertoli cell (SCARKO) to examine how FSH and androgen combine to regulate Sertoli cell function and spermatogenesis. Sertoli cell number in FSHRKO-SCARKO mice was reduced by about 50% but was not significantly different from FSHRKO mice. In contrast, total germ cell number in FSHRKO-SCARKO mice was reduced to 2% of control mice (and 20% of SCARKO mice) due to a failure to progress beyond early meiosis. Measurement of Sertoli cell-specific transcript levels showed that about a third were independent of hormonal action on the Sertoli cell, whereas others were predominantly androgen dependent or showed redundant control by FSH and androgen. Results show that FSH and androgen act through redundant, additive, and synergistic regulation of spermatogenesis and Sertoli cell activity. In addition, the Sertoli cell retains a significant capacity for activity, which is independent of direct hormonal regulation.
Publication
Journal: Fertility and Sterility
July/14/2008
Abstract
OBJECTIVE
To investigate the effects of Müllerian-inhibiting substance (MIS) on cytochrome P450 aromatase (CYP19) gene expression in cultured human granulosa lutein cells (GLC).
METHODS
In vitro primary cell culture study.
METHODS
Academic research laboratory and hospital-based fertility center.
METHODS
Eight normo-ovulatory patients undergoing IVF procedures due to male factor or tubal infertility.
METHODS
Serum and follicular fluid (FF) collected and stored at -80 degrees C until assayed. Granulosa lutein cells were harvested from follicular aspirates obtained during oocyte retrieval and cultured for 7 days with media in the presence or absence of MIS (10 ng/mL) or FSH 0.2 IU/mL.
METHODS
Serum and FF levels of E2 and MIS, and E2 production by GLC in culture. Levels of CYP19 mRNA in cultured GLC were determined by quantitative polymerase chain reaction (PCR) and CYP19 protein by Western blot. Statistical comparison used ANOVA and post hoc Tukey tests.
RESULTS
Follicle-stimulating hormone significantly increased E2 production in cultured GLC compared with control. The increase in E2 production is associated with higher levels of CYP19 mRNA and protein in GLC. The presence of MIS significantly inhibited FSH-induced E2 production, with concomitant reduction in CYP19mRNA and protein levels.
CONCLUSIONS
Müllerian-inhibiting substance inhibits FSH augmentation of CYP19 enzyme activity and CYP19 gene expression in GLC. These findings may help to explain the association of high MIS levels and low FF E2 levels reported in women with polycystic ovary syndrome (PCOS).
Publication
Journal: Journal of Epidemiology and Community Health
September/29/2011
Abstract
OBJECTIVE
To assess the risk of autism spectrum disorders (ASD) in children born after assisted conception compared with children born after natural conception.
METHODS
Population-based follow-up study.
METHODS
All children born alive in Denmark 1995-2003.
METHODS
588,967 children born in Denmark from January 1995 to December 2003. Assisted conception was defined as in vitro fertilisation (IVF) with or without intracytoplasmic sperm injection and ovulation induction (OI) with or without subsequent insemination. Children exposed to IVF or OI were identified in the IVF Register and in the Danish Drug Prescription Register.
METHODS
A diagnosis of ASD in the Danish Psychiatric Central Register.
RESULTS
33,139 (5.6%) of all children born in Denmark in 1995-2003 resulted from assisted conception, 225 of whom (0.68%) had a diagnosis of ASD. Of the 555,828 children born in this period after natural conception, 3394 (0.61%) had a diagnosis of ASD. The follow-up time was 4-13 years (median 9 years). In crude analyses, children born after assisted conception had an increased risk of a diagnosis of ASD: crude hazard rate ratio (HRR) 1.25 (95% CI 1.09 to 1.43). In analyses adjusting for maternal age, educational level, parity, smoking, birth weight and multiplicity, the risk disappeared: adjusted HRR 1.13. (95% CI 0.97 to 1.31). However, subgroup analyses that suggest possible associations in women who received follicle stimulating hormone indicate the need for further study.
CONCLUSIONS
This population-based follow-up study found no risk of ASD in children born after assisted conception.
Publication
Journal: Obstetrics and Gynecology
March/11/2002
Abstract
OBJECTIVE
To examine the change in menopausal symptoms and cardiovascular risk factors in response to 4 months of daily 100-mg soy isoflavone in postmenopausal women.
METHODS
In this double-blind, placebo-controlled study, 80 women were randomly assigned to isoflavone (n = 40) and placebo (n = 40) treatment. The menopausal Kupperman index was used to assess change in menopausal symptoms at baseline and after 4 months of treatment. Cardiovascular risk factors were assessed by evaluating plasma lipid levels, body mass index, blood pressure, and glucose levels in the participants. To examine the effects of this regime on endogenous hormone levels, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and 17 beta-estradiol were measured. Transvaginal sonography was performed to quantify endometrial thickness.
RESULTS
The data showed a decrease in menopausal symptoms (P <.01, paired t test, two-tailed, between baseline and isoflavone groups, and P <.01, unpaired t test, between placebo and isoflavone groups). Total cholesterol and low-density lipoprotein decreased significantly in the isoflavone group compared with the baseline or placebo group (P <.001, paired t test, two-tailed, between baseline and isoflavone groups, and P <.01, unpaired t test, between placebo and isoflavone groups). The isoflavone treatment appeared to have no effect on blood pressure, plasma glucose, and high-density lipoprotein and triglyceride levels.
CONCLUSIONS
This study suggests that isoflavone 100-mg regime treatment may be a safe and effective alternative therapy for menopausal symptoms and may offer a benefit to the cardiovascular system.
Publication
Journal: European Journal of Clinical Investigation
July/20/2003
Abstract
BACKGROUND
Because there is reason to assume that also in Austria calcium and vitamin D malnutrition is wide-spread, we initiated a comprehensive study on calcium and vitamin D status in relation to bone health in a large group of the normal adult population.
METHODS
We assessed dietary calcium and vitamin D intake, serum concentrations of Ca2+, phosphate, alkaline phosphatase, 25(OH)D, 1,25(OH)2D, parathyroid hormone (PTH), follicle-stimulating hormone (FSH), sex hormones and bone mineral density (BMD) by double-energy X-ray absorptiometry at five different skeletal sites in 648 females and 400 males (age 21-76 years).
RESULTS
Mean daily intake of vitamin D (101 IU, range 0.2-320) and calcium (569 mg, range 40-2170) was significantly less than the respective recommended dietary allowances. Two hundred and seventy-one (26%) individuals had hypovitaminosis D with serum 25(OH)D < 12 ng mL(-1), while serum Ca2+ was less than normal in 82 (7.8%) subjects. Multiple regression analysis revealed significant correlations between mean calcium intake and BMD in the femoral region in the men (r = 0.13, P < 0.05) though not in the women. No consistent data could be obtained for associations between BMD and vitamin D status, except for 25(OH)D and BMD at the spine in the men (r = 0.10, P < 0.05). 25(OH)D correlated negatively (P < 0.05) with age in the women (r = -0.11) and with PTH in the women (r = -0.11) and men (r = -0.16). Inversely, a significant (P < 0.001) age-related increase in PTH was observed in both sexes (men, r = 0.19; women, r = 0.14).
CONCLUSIONS
Prevalence of hypovitaminosis D in adult Austrians is an imminent risk for development of secondary hyperparathyroidism with advancing age, and requires timely correction of nutritional deficits.
Publication
Journal: Environmental Health Perspectives
September/19/2013
Abstract
BACKGROUND
Perfluorinated alkyl acids (PFAAs), persistent chemicals with unique water-, dirt-, and oil-repellent properties, are suspected of having endocrine-disrupting activity. The PFAA compounds perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are found globally in humans; because they readily cross the placental barrier, in utero exposure may be a cause for concern.
OBJECTIVE
We investigated whether in utero exposure to PFOA and PFOS affects semen quality, testicular volume, and reproductive hormone levels.
METHODS
We recruited 169 male offspring (19-21 years of age) from a pregnancy cohort established in Aarhus, Denmark, in 1988-1989, corresponding to 37.6% of the eligible sons. Each man provided a semen sample and a blood sample. Semen samples were analyzed for sperm concentration, total sperm count, motility, and morphology, and blood samples were used to measure reproductive hormones. As a proxy for in utero exposure, PFOA and PFOS were measured in maternal blood samples from pregnancy week 30.
RESULTS
Multivariable linear regression analysis suggested that in utero exposure to PFOA was associated with lower adjusted sperm concentration (ptrend = 0.01) and total sperm count (ptrend = 0.001) and with higher adjusted levels of luteinizing hormone (ptrend = 0.03) and follicle-stimulating hormone (ptrend = 0.01). PFOS did not appear to be associated with any of the outcomes assessed, before or after adjustment.
CONCLUSIONS
The results suggest that in utero exposure to PFOA may affect adult human male semen quality and reproductive hormone levels.
Publication
Journal: Molecular and Cellular Endocrinology
September/19/2001
Abstract
The ability of gonadotropins to act on and regulate normal ovarian surface epithelial (OSE) cells and ovarian cancer cells was investigated. Bovine OSE was used as a model to study normal OSE. Results demonstrate that follicle stimulating hormone (FSH) and the luteinizing hormone (LH) like molecule, human chorionic gonadotropin (hCG), can both stimulate (3H)-thymidine incorporation into DNA in normal OSE cells. Similar results were obtained using either purified hormones or recombinant human hormones. A human ovarian cancer cell-line OCC1 was also stimulated to grow in response to FSH and hCG, but the growth of a different human ovarian cancer cell-line SKOV3 was not affected. In addition to effects on cell growth, gonadotropins also stimulated growth factor expression. Both FSH and hCG stimulated steady state levels of keratinocyte growth factor (KGF), hepatocyte growth factor (HGF), and kit ligand (KL) mRNA in OSE cells. Previously, KGF, HGF, and KL have been shown to stimulate OSE growth. Both follicle stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHR) were observed in OSE cells by Northern blot analysis. Reverse transcription polymerase chain reaction (RT-PCR) analysis was performed on fresh and cultured OSE cells. Normal OSE was found to express FSHR and LHR both in vivo and in vitro. The PCR reaction products were sequenced and found to provide a 100% homology with the bovine gonadotropin receptor sequences previously reported. FSHR and LHR transcripts were also detected in gonadotropin responsive OCC1 cells, but not in the gonadotropin insensitive SKOV3 cells. Observations support the hypothesis that gonadotropins may influence some ovarian cancers. In summary, the current study demonstrates the novel observation that both the FSHR and LHR are expressed by bovine OSE and selected ovarian cancers. Interestingly, the actions of FSH and LH to promote OSE growth may in part be mediated indirectly through an elevation in the expression of autocrine growth factors (KGF, HGF, and KL). Ovarian cancer is more common in conditions with elevated gonadotropins such as post-menopausal women. Therefore, gonadotropin actions on the OSE are postulated to be a potential factor in the onset and progression of some ovarian cancers.
Publication
Journal: Endocrine
March/7/2011
Abstract
MicroRNAs (miRNAs) regulate gene expression post-transcriptionally by interacting with the 3' untranslated regions of their target mRNAs. Previously, miRNAs have been shown to regulate genes involved in cell growth, apoptosis, and differentiation, but their role in ovarian granulosa cell follicle-stimulating hormone (FSH)-stimulated steroidogenesis is unclear. Here we show that expression of 31 miRNAs is altered during FSH-mediated progesterone secretion of cultured granulosa cells. Specifically, 12 h after FSH treatment, miRNAs mir-29a and mir-30d were significantly down-regulated. However, their expression increased after 48 h. Bioinformatic analysis used to predict potential targets of mir-29a and mir-30d revealed a wide array of potential mRNA target genes, including those encoding genes involved in multiple signaling pathways. Taken together, our results pointed to a novel mechanism for the pleiotropic effects of FSH.
Publication
Journal: Journal of Bone and Mineral Research
September/23/1998
Abstract
There is a need to better understand potential bone mineral density (BMD) loss during the menopausal transition since this period may include the initiation of interventions. The study purpose was to determine if there was BMD loss at the femoral neck, lumbar spine, or total body bone sites in a population-based study of women approaching or transitioning the midlife. The 583 enrollees were 25-45 years of age at the first of four annual measurements from 1992 through 1996. Bone mineral content and bone width were measured using dual-energy X-ray absorptiometry. Considering all enrollees collectively, there was a significant 3-year decline (1%) in BMD at the femoral neck over the 3-year period (p = 0.076). There was no significant annual change in the lumbar spine (p = 0.11), and a significant annual increase in the total body BMD (p = 0.0003). Within subgroups and cross-sectionally, BMD values of the femoral neck were 5% lower in women classified as perimenopausal compared with premenopausal enrollees; BMD was 3% and 1% lower at the lumbar spine and total body site, respectively. Longitudinally, among perimenopausal women, a double oophorectomy was associated with BMD loss in the spine (p = 0.0003), even though 75-85% of these women had a hormone replacement prescription at some time during the study period. In summary, the site with evidence of loss was the femoral neck, specifically among perimenopausal women. There was little evidence of substantial total body or lumbar spine BMD loss in premenopausal women with ovaries who maintained follicle-stimulating hormone levels < 20 mIU/l in the early follicular period. Double oophorectomy, even with hormone replacement, was associated with bone loss.
Publication
Journal: Molecular and Cellular Biology
February/11/2010
Abstract
Oscillatory synthesis and secretion of the gonadotropins, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), under the control of pulsatile hypothalamic gonadotropin-releasing hormone (GnRH), is essential for normal reproductive development and fertility. The molecular mechanisms by which various patterns of pulsatile GnRH regulate gonadotrope responsiveness remain poorly understood. In contrast to the alpha and LH beta subunit genes, FSH beta subunit transcription is preferentially stimulated at low rather than high frequencies of pulsatile GnRH. In this study, mutation of a cyclic AMP response element (CRE) within the FSH beta promoter resulted in the loss of preferential GnRH stimulation at low pulse frequencies. We hypothesized that high GnRH pulse frequencies might stimulate a transcriptional repressor(s) to attenuate the action of CRE binding protein (CREB) and show that inducible cAMP early repressor (ICER) fulfills such a role. ICER was not detected under basal conditions, but pulsatile GnRH stimulated ICER to a greater extent at high than at low pulse frequencies. ICER binds to the FSH beta CRE site to reduce CREB occupation and abrogates both maximal GnRH stimulation and GnRH pulse frequency-dependent effects on FSH beta transcription. These data suggest that ICER production antagonizes the stimulatory action of CREB to attenuate FSH beta transcription at high GnRH pulse frequencies, thereby playing a critical role in regulating cyclic reproductive function.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
May/12/2002
Abstract
Targeted disruption of exon 9 of the cyp19 gene gives rise to a non-functional aromatase enzyme incapable of converting androgens to oestrogens. The aromatase knockout (ArKO) mouse is, thus, characterised by a dysfunctional pituitary-gonadal axis, which manifests in non-detectable levels of oestrogen in serum. These mice also exhibit elevated levels of circulating gonadotrophins (luteinising hormone (LH) and follicle stimulating hormone (FSH)) and testosterone. The ArKO mouse is infertile due to folliculogenic disruption and a failure to ovulate. The age-dependent ovarian phenotype revealed a block in follicular development at the antral stage and a complete absence of corpora lutea. By 21-23 weeks of age haemorrhagic cystic follicles were present and by 1 year there were abnormal follicles, an absence of secondary and antral follicles and atretic primary follicles. Interstitial tissue remodelling was extensive and exemplified by an increase in collagen deposition and an influx of macrophages, coincident with the loss of follicles. In mice, maintained on a soy-free and, thus, phytoestrogen-free diet, the ovarian phenotype was accelerated and exacerbated. In conclusion, the ovarian phenotype of the ArKO mouse can be attributed to the altered hormonal environment brought about by the absence of aromatase and the failure of androgens to be converted to oestrogens in the presence of elevated gonadotropins.
Publication
Journal: Nature
August/13/1986
Abstract
One in 10,000 children develops Wilms' tumour, an embryonal malignancy of the kidney. Although most Wilms' tumours are sporadic, a genetic predisposition is associated with aniridia, genito-urinary malformations and mental retardation (the WAGR syndrome). Patients with this syndrome typically exhibit constitutional deletions involving band p13 of one chromosome 11 homologue. It is likely that these deletions overlap a cluster of separate but closely linked genes that control the development of the kidney, iris and urogenital tract (the WAGR complex). A discrete aniridia locus, in particular, has been defined within this chromosomal segment by a reciprocal translocation, transmitted through three generations, which interrupts 11p13. In addition, the specific loss of chromosome 11p alleles in sporadic Wilms' tumours has been demonstrated, suggesting that the WAGR complex includes a recessive oncogene, analogous to the retinoblastoma locus on chromosome 13. In WAGR patients, the inherited 11p deletion is thought to represent the first of two events required for the initiation of a Wilms' tumour, as suggested by Knudson from epidemiological data. We have now isolated the deleted chromosomes 11 from four WAGR patients in hamster-human somatic cell hybrids, and have tested genomic DNA from the hybrids with chromosome 11-specific probes. We show that 4 of 31 markers are deleted in at least one patient, but that of these markers, only the gene encoding the beta-subunit of follicle-stimulating hormone (FSHB) is deleted in all four patients. Our results demonstrate close physical linkage between FSHB and the WAGR locus, suggest a gene order for the four deleted markers and exclude other markers tested from this region. In hybrids prepared from a balanced translocation carrier with familial aniridia, the four markers segregate into proximal and distal groups. The translocation breakpoint, which identifies the position of the aniridia gene on 11p, is immediately proximal to FSHB, in the interval between FSHB and the catalase gene.
Publication
Journal: Human Reproduction
December/4/1997
Abstract
A systematic review was conducted to evaluate the effectiveness of intrauterine insemination (IUI) with or without ovarian stimulation using gonadotrophin in the treatment of persistent infertility. Relevant randomized controlled trials were identified by a diverse strategy including a hand search of 43 core journals from 1966 to the present. Two approaches to meta-analysis were used to summarize data. First, using a standard Mantel-Haenszel approach, eight trials comparing FSH/IUI with FSH/timed intercourse for unexplained infertility were combined. The common odds ratio for pregnancy was 2.37 [95% confidence interval (CI), 1.43, 3.90], suggesting a significant improvement with IUI following ovulation induction in this patient group. Although the data were statistically homogeneous, clinically important heterogeneity was present. Second, across all diagnostic groups, the independent effects of treatment with follicle stimulating hormone (FSH), clomiphene citrate, IUI, as well as the diagnoses of male factor and endometriosis were assessed using stepwise logistic regression. Based on 5214 cycles reported in 22 trials, the odds ratio for pregnancy associated with FSH use was 2.35 (95% CI, 1.87, 2.94) for IUI, 2.82 (95% CI, 2.18, 3.66) for male factor, 0.48 (95% CI, 0.37, 0.61), and for endometriosis 0.45 (95% CI, 0.27, 0.76). This summary of the best available evidence may prove useful in counselling couples who are considering FSH and/or IUI therapy.
Authors
Publication
Journal: Journal of Women's Health
October/18/2007
Abstract
OBJECTIVE
To determine whether hot flashes, depressed mood, sleep, cognitive and sexual symptoms correlate with urinary follicle-stimulating hormone (FSH), estrone (E(1)G), and testosterone (T) and with each other during the menopausal transition and early postmenopause (PM).
METHODS
Forty-one women who transitioned from middle or late transition stage to PM rated symptoms and provided monthly urine specimens as part of a longitudinal study of the menopausal transition.
RESULTS
Correlations between endocrine levels and symptom severity ratings over time revealed that hot flash severity was significantly and positively related to FSH and negatively to E1 G. Vaginal dryness was positively correlated with FSH and negatively correlated with T. Decreased sexual desire was correlated negatively with E(1)G levels. Forgetfulness was positively correlated with FSH; difficulty concentrating was negatively correlated with T. Severity of sleep symptoms and depressed mood were not correlated with E(1)G, FSH, or T. Correlations among the symptoms revealed that severity of hot flashes was associated with sleep disruption and forgetfulness. Depressed mood was correlated with sleep disruption, difficulty concentrating, and decreased sexual desire but not with hot flashes or vaginal dryness. Awakening during the night was correlated with decreased sexual desire and vaginal dryness, as well as hot flashes. Forgetfulness was associated with hot flashes and difficulty concentrating, whereas difficulty concentrating was associated with depressed mood and early awakening.
CONCLUSIONS
Symptoms many women experience during the menopausal transition and early PM are related to different endocrine levels (FSH, E(1)G, and T).
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