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Publication
Journal: Journal of Clinical Endocrinology and Metabolism
October/23/2012
Abstract
BACKGROUND
Variability in the pattern of change in estradiol (E2) and FSH levels over the menopause transition has not been well defined.
OBJECTIVE
The current study aimed to determine whether different trajectories of E2 and FSH could be identified and whether race/ethnicity and body mass index were related to the different trajectories.
METHODS
The Study of Women's Health Across the Nation is a longitudinal observational study of the menopausal transition.
METHODS
Women aged 42-52 yr from seven participating sites were recruited and underwent up to 11 annual visits.
METHODS
Postmenopausal women with 12 or more months of amenorrhea that was not due to hysterectomy/oophorectomy and who were not using hormone therapy before the final menstrual period participated in the study.
METHODS
Annual serum E2 and FSH levels anchored to final menstrual period were measured.
RESULTS
Four distinct E2 trajectories and three distinct FSH trajectories were identified. The E2 trajectories were: slow decline (26.9%), flat (28.6%), rise/slow decline (13.1%), and rise/steep decline (31.5%). The FSH trajectories were: low (10.6%), medium (48.7%), and high (41.7%) rising patterns. Obesity increased the likelihood of a flat E2 and low FSH trajectory for all race/ethnic groups. Normal-weight Caucasian and African-American women tended to follow the rise/steep decline E2 and high FSH trajectories. Normal-weight Chinese/Japanese women tended to follow the slow decline E2 and the high/medium FSH trajectories.
CONCLUSIONS
E2 and FSH trajectories over the menopausal transition are not uniform across the population of women. Race/ethnicity and body mass index affect the trajectory of both E2 and FSH change over the menopausal transition.
Publication
Journal: Gynecologic Oncology
June/27/2013
Abstract
OBJECTIVE
The objective of this study is to compare ovarian function and surgical outcomes between patients affected by benign uterine pathologies submitted to total laparoscopic hysterectomy (TLH) plus salpingectomy and women in which standard TLH with adnexal preservation was performed.
METHODS
We retrospectively compared data of 79 patients who underwent TLH plus bilateral salpingectomy (group A), with those of 79 women treated by standard TLH without adnexectomy (sTLH) (group B). Ovarian reserve modification, expressed as the difference between 3 months post-operative and pre-operative values of Anti-Müllerian Hormone (AMH), Follicle Stimulating Hormone (FSH), Antral Follicle Count (AFC), mean ovarian diameters and Peak Systolic Velocity (PSV), was recorded for each patient. For each surgical procedure, operative time, variation of hemoglobin level (ΔHb), postoperative hospital stay, postoperative return to normal activity, and complication rate were recorded as secondary outcomes.
RESULTS
According to our post-hoc analysis, this equivalence study resulted to have a statistical power of 96.8%. Significant difference was not observed between groups with respect to ΔAMH (p=0.35), ΔFSH (p=0.15), ΔAFC (p=0.09), Δ mean ovarian diameters (p=0.57) and ΔPSV (p=0.61). In addition, secondary outcomes such as operative time (p=0.79), ΔHb (p=0.41), postoperative hospital stay (p=0.16), postoperative return to normal activity (p=0.11) and complication rate also did not show any significant difference.
CONCLUSIONS
The addition of bilateral salpingectomy to TLH for prevention of ovarian cancer in women who do not carry a BRCA1/2 mutations do not show negative effects on the ovarian function. In addition, no perioperative complications are related to the salpingectomy step in TLH.
Publication
Journal: Journal of the American Chemical Society
June/29/2009
Abstract
A highly convergent synthesis of the sialic acid-rich biantennary N-linked glycan found in human glycoprotein hormones and its use in the synthesis of a fragment derived from the beta-domain of human Follicle-Stimulating Hormone (hFSH) are described. The synthesis highlights the use of the Sinay radical glycosidation protocol for the simultaneous installation of both biantennary side-chains of the dodecasaccharide as well as the use of glycal chemistry to construct the tetrasaccharide core in an efficient manner. The synthetic glycan was used to prepare the glycosylated 20-27aa domain of the beta-subunit of hFSH under a Lansbury aspartylation protocol. The proposed strategy for incorporating the prepared N-linked dodecasaccharide-containing 20-27aa domain into beta-hFSH subunit was validated in the context of a model system, providing protected beta-hFSH subunit functionalized with chitobiose at positions 7 and 24.
Publication
Journal: BioMetals
May/18/2005
Abstract
In 123 Croatian men with no occupational exposure to metals, the influence of cadmium on reproductive parameters was examined after adjusting for age, smoking, alcohol, and biomarkers of lead, copper, zinc, and selenium. The following variables were measured: blood cadmium (BCd), blood lead (BPb), activity of delta-aminolevulinic acid dehydratase (ALAD), erythrocyte protoporphyrin, serum copper (SCu), serum zinc (SZn), serum selenium (SSe), activity of glutathione peroxidase (GPx) in blood, testis size, semen quality (including sperm concentration, motility, viability, and morphology), indicators in seminal fluid (the lactate dehydrogenase isoenzyme LDH-C4, fructose, zinc, acid phosphatase, and citric acid), and hormones in serum (follicle-stimulating hormone--FSH, luteinizing hormone, prolactin, testosterone, and estradiol). The median and range BCd values were 2.94 (0.49-11.93) microg/L in 61 smokers and 0.59 (0.20-3.71) microg/L in 62 nonsmokers (p < 0.0001). Smoking habits (cigarettes/day) highly significantly correlated with BCd (p < 0.0001). After adjusting for potential confounding variables by multiple regression, BCd was significantly associated with a decrease in testis size (p < 0.03) and an increase in serum estradiol (p < 0.005), FSH (p < 0.03), and testosterone (p < 0.04). Smoking was significantly associated with a decrease in serum prolactin (p < 0.006) and LDH-C4 in seminal fluid (p < 0.03). Several reproductive parameters were significantly associated with BPb and ALAD, biomarkers of lead, and/or with SCu, SZn, SSe, and GPx. The necessity of controlling for various metals, and other potential confounders when assessing the influence of a particular metal on reproductive function in men, is emphasized.
Publication
Journal: Endocrinology
June/20/2001
Abstract
FSH is produced in pituitary gonadotropes as an alpha/beta heterodimer, and synthesis of the beta-subunit is the rate-limiting step in overall FSH production. Synthesis of FSHbeta can be regulated by activin and inhibin, both of which are members of the transforming growth factor-beta superfamily. Bone morphogenetic proteins (BMPs) also belong to the transforming growth factor-beta family and are multifunctional growth factors involved in many aspects of tissue development and morphogenesis, including regulation of FSH action in the ovary. Here we report a novel function for BMP-7 and BMP-6 in regulating FSH synthesis in the pituitary. Using primary pituitary cell cultures derived from transgenic mice that carry the ovine FSHbeta promoter linked to a luciferase reporter gene (oFSHbetaLuc), BMP-7 or BMP-6 was found to stimulate oFSHbetaLuc expression by 6-fold. Transient expression of the oFSHbetaLuc in a transformed gonadotrope cell line, LbetaT2, was induced 4-fold by BMP-7 or BMP-6 treatment. More importantly, BMP-7 and BMP-6 increased endogenous FSH secretion by 10- and 14-fold, respectively, from LbetaT2 cells, demonstrating for the first time that a functional signaling BMP system is present in gonadotropes. Two bioneutralizing antibodies to BMP-7, which cross-react with BMP-6, but not with activin A, decreased basal oFSHbetaLuc expression and FSH secretion from transgenic mouse pituitary cultures by 83-88% and 47-48%, respectively, suggesting an autocrine or paracrine role for BMP-7 or BMP-6 in FSH synthesis. Neither bioneutralizing antibody to activin A or activin B decreased basal oFSHbetaLuc expression or mouse FSH secretion significantly. Dose-dependent inhibition of FSH synthesis by anti-BMP7 was also observed in rat and sheep pituitary cultures. These results combined with the fact that the messenger RNAs for BMP-7 and BMP-6 were detected in mouse pituitaries and LbetaT2 cells indicate that BMP-7 and/or BMP-6 can function as FSH stimulators and may be significant physiological factors maintaining basal FSH expression in vivo.
Publication
Journal: Reproductive Biology and Endocrinology
February/14/2010
Abstract
BACKGROUND
Women have been able to delay childbearing since effective contraception became available in the 1960s. However, fertility decreases with increasing maternal age. A slow but steady decrease in fertility is observed in women aged between 30 and 35 years, which is followed by an accelerated decline among women aged over 35 years. A combination of delayed childbearing and reduced fecundity with increasing age has resulted in an increased number and proportion of women of greater than or equal to 35 years of age seeking assisted reproductive technology (ART) treatment.
METHODS
Literature searches supplemented with the authors' knowledge.
RESULTS
Despite major advances in medical technology, there is currently no ART treatment strategy that can fully compensate for the natural decline in fertility with increasing female age. Although chronological age is the most important predictor of ovarian response to follicle-stimulating hormone, the rate of reproductive ageing and ovarian sensitivity to gonadotrophins varies considerably among individuals. Both environmental and genetic factors contribute to depletion of the ovarian oocyte pool and reduction in oocyte quality. Thus, biological and chronological ovarian age are not always equivalent. Furthermore, biological age is more important than chronological age in predicting the outcome of ART. As older patients present increasingly for ART treatment, it will become more important to critically assess prognosis, counsel appropriately and optimize treatment strategies. Several genetic markers and biomarkers (such as anti-Müllerian hormone and the antral follicle count) are emerging that can identify women with accelerated biological ovarian ageing. Potential strategies for improving ovarian response include the use of luteinizing hormone (LH) and growth hormone (GH). When endogenous LH levels are heavily suppressed by gonadotrophin-releasing hormone analogues, LH supplementation may help to optimize treatment outcomes for women with biologically older ovaries. Exogenous GH may improve oocyte development and counteract the age-related decline of oocyte quality. The effects of GH may be mediated by insulin-like growth factor-I, which works synergistically with follicle-stimulating hormone on granulosa and theca cells.
CONCLUSIONS
Patients with biologically older ovaries may benefit from a tailored approach based on individual patient characteristics. Among the most promising adjuvant therapies for improving ART outcomes in women of advanced reproductive age are the administration of exogenous LH or GH.
Publication
Journal: Journal of Ovarian Research
April/7/2013
Abstract
BACKGROUND
Follicle stimulating hormone (FSH) exerts action on both germline and somatic compartment in both ovary and testis although FSH receptors (FSHR) are localized only on the somatic cells namely granulosa cells of growing follicles and Sertoli cells in the seminiferous tubules. High levels of FSH in females are associated with poor ovarian reserve, ovarian hyper stimulation syndrome etc. and at the same time FSH acts as a survival factor during in vitro organotypic culture of ovarian cortical strips. Thus a further understanding of FSH action on the ovary is essential. We have earlier reported presence of pluripotent very small embryonic-like stem cells (VSELs express Oct-4A in addition to other pluripotent markers) and their immediate descendants 'progenitors' ovarian germ stem cells (OGSCs express Oct-4B in addition to other germ cell markers) in ovarian surface epithelium (OSE) in various mammalian species including mice, rabbit, monkey, sheep and human. Present study was undertaken to investigate the effect of pregnant mare serum gonadotropin (PMSG) on adult mice ovaries with a focus on VSELs, OGSCs, postnatal oogenesis and primordial follicle assembly.
METHODS
Ovaries were collected from adult mice during different stages of estrus cycle and after 2 and 7 days of PMSG (5 IU) treatment to study histo-architecture and expression for FSHR, pluripotent stem cells , meiosis and germ cell specific markers.
RESULTS
PMSG treatment resulted in increased FSHR and proliferation as indicated by increased FSHR and PCNA immunostaining in OSE and oocytes of primordial follicles (PF) besides the granulosa cells of large antral follicles. Small 1-2 regions of multilayered OSE invariably associated with a cohort of PF during estrus stage in control ovary were increased to 5-8 regions after PMSG treatment. This was associated with an increase in pluripotent transcripts (Oct-4A, Nanog), meiosis (Scp-3) and germ cells (Oct-4B, Mvh) specific markers. MVH showed positive immuno staining on germ cell nest-like clusters and at places primordial follicles appeared connected through oocytes.
CONCLUSIONS
The results of the present study show that gonadotropin (PMSG) treatment to adult mouse leads to increased pluripotent stem cell activity in the ovaries, associated with increased meiosis, appearance of several cohorts of PF and their assembly in close proximity of OSE. This was found associated with the presence of germ cell nests and cytoplasmic continuity of oocytes in PF. We have earlier reported that pluripotent ovarian stem cells in the adult mammalian ovary are the VSELs which give rise to slightly differentiated OGSCs. Thus we propose that gonadotropin through its action on pluripotent VSELs augments neo-oogenesis and PF assembly in adult mouse ovaries.
Publication
Journal: Journal of Urology
March/29/1987
Abstract
The testicular sizes of 305 men were measured by a recently developed orchidometer and related to 9 other known parameters of testicular function. Mean testicular size had the strongest correlation with serum follicle-stimulating hormone levels, total sperm count and sperm concentration, while a significant correlation also was noted with sperm motility, percentage of live sperm, sperm morphology (normal and immature forms), and serum luteinizing hormone and testosterone levels. Sperm quantity had stronger correlations with testicular size than did sperm quality, although both were impaired in testes smaller than 14 ml. It is concluded that the size of the testis bears a direct correlation with testicular function and, thus, it can be helpful to assess rapidly andrological status during the initial physical examination.
Publication
Journal: Biology of Reproduction
May/21/2015
Abstract
Expression and function of the follicle-stimulating hormone receptor (FSHR) in females were long thought to be limited to the ovary. Here, however, we identify extragonadal FSHR in both the human female reproductive tract and the placenta, and test its physiological relevance in mice. We show that in nonpregnant women FSHR is present on: endothelial cells of blood vessels in the endometrium, myometrium, and cervix; endometrial glands of the proliferative and secretory endometrium; cervical glands and the cervical stroma; and (at low levels) stromal cells and muscle fibers of the myometrium. In pregnant women, placental FSHR was detected as early as 8-10 wk of gestation and continued through term. It was expressed on: endothelial cells in fetal portions of the placenta and the umbilical cord; epithelial cells of the amnion; decidualized cells surrounding the maternal arteries in the maternal decidua; and the stromal cells and muscle fibers of the myometrium, with particularly strong expression at term. These findings suggest that FSHR expression is upregulated during decidualization and upregulated in myometrium as a function of pregnancy. The presence of FSHR in the placental vasculature suggests a role in placental angiogenesis. Analysis of genetically modified mice in which Fshr is lacking in fetal portions of the placenta revealed adverse effects on fetoplacental development. Our data further demonstrate FSHB and CGA mRNAs in placenta and uterus, consistent with potential local sources of FSH. Collectively, our data suggest heretofore unappreciated roles of extragonadal FSHR in female reproductive physiology.
Publication
Journal: American Journal of Obstetrics and Gynecology
August/30/2017
Abstract
Ovarian reserve is a complex clinical phenomenon influenced by age, genetics, and environmental variables. Although it is challenging to predict the rate of an individual's ovarian reserve decline, clinicians are often asked for advice about fertility potential and/or recommendations regarding the pursuit of fertility treatment options. The purpose of this review is to summarize the state-of-the-art of ovarian reserve testing, providing a guide for the obstetrician/gynecologist generalist and reproductive endocrinologist. The ideal ovarian reserve test should be convenient, be reproducible, display little if any intracycle and intercycle variability, and demonstrate high specificity to minimize the risk of wrongly diagnosing women as having diminished ovarian reserve and accurately identify those at greatest risk of developing ovarian hyperstimulation prior to fertility treatment. Evaluation of ovarian reserve can help to identify patients who will have poor response or hyperresponse to ovarian stimulation for assisted reproductive technology. Ovarian reserve testing should allow individualization of treatment protocols to achieve optimal response while minimizing safety risks. Ovarian reserve testing may inform patients regarding their reproductive lifespan and menopausal timing as well as aid in the counselling and selection of treatment for female cancer patients of reproductive age who receive gonadotoxic therapy. In addition, it may aid in establishing the diagnosis of polycystic ovary syndrome and provide insight into its severity. While there is currently no perfect ovarian reserve test, both antral follicular count and antimüllerian hormone have good predictive value and are superior to day-3 follicle-stimulating hormone. The convenience of untimed sampling, age-specific values, availability of an automated platform, and potential standardization of antimüllerian hormone assay make this test the preferred biomarker for the evaluation of ovarian reserve in women.
Publication
Journal: Developmental Biology
January/26/1993
Abstract
Follicle-stimulating hormone (FSH) and its intracellular mediator, cAMP, increase the mRNA levels for the Steel factor (SLF, the c-kit ligand) in cultured primary mouse Sertoli cells. The inductive effect of cAMP is more evident in cultures from 13-day-old animals than in cultures from 18-day-old animals. Analysis through the polymerase chain reaction (PCR) indicates that (Bu)2cAMP or FSH treatment increases the levels of the mRNAs for both the potentially soluble form and the transmembrane form of SLF in cultured Sertoli cells. The ratio between mRNAs encoding the potentially soluble form and the transmembrane form of SLF increases during postnatal testis development, and it is higher in cultured Sertoli cells with respect to total testis, suggesting that, under the in vitro conditions, SLF could be produced by Sertoli cells mainly as a soluble factor. Soluble recombinant SLF stimulates, in a dose-dependent fashion, thymidine incorporation in cultures of isolated germ cell populations enriched in the mitotic stages (spermatogonia), independently of the presence of serum, whereas cAMP analogs have no effect. Autoradiographic analysis shows that SLF selectively stimulates DNA synthesis in type A spermatogonia.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
February/28/1985
Abstract
Neuropeptide Y (NPY) has recently been localized in the rat hypothalamus. We have evaluated the effects of NPY on hypothalamic and pituitary function by injecting NPY into the third ventricle in vivo and by examining its action on perifused pituitary cells in vitro. Injections of NPY into the third ventricle of conscious ovariectomized rats led to a dramatic and highly significant reduction in plasma luteinizing hormone (LH) relative to pretreatment levels in these animals or to those of controls injected with physiological saline. Significant inhibition was obtained with doses ranging from 0.02 to 5.0 micrograms (4.7-1175 pmol) of NPY. These inhibitory effects on LH release were dose dependent and lasted for at least 120 min after injection of 5.0 micrograms of NPY. Intraventricular injection of NPY also significantly decreased plasma growth hormone; however, the threshold dose was 2.0 micrograms (470 pmol), a dose 100-fold greater than the lowest dose that inhibited LH release. Plasma follicle-stimulating hormone was unaffected by injection of NPY. NPY (10(-6) and 10(-7) M) stimulated secretion of LH, growth hormone, and follicle-stimulating hormone from perifused anterior pituitary cells loaded in a Bio-Gel P-2 column. These results indicate that NPY acts on structures adjacent to the third ventricle to inhibit the secretion of LH and growth hormone but not follicle-stimulating hormone, whereas it can directly stimulate the secretion of all three hormones from the cells of the anterior pituitary in vitro. Since NPY has been found in the hypothalamus and median eminence, it is quite likely that it plays a physiologically significant role at both hypothalamic and pituitary sites: influencing secretion of pituitary hormones.
Publication
Journal: Biochemical and Biophysical Research Communications
October/2/1986
Abstract
A 24,000 Dalton protein with follicle stimulating hormone (FSH)-releasing activity, named activin, has been characterized previously from porcine follicular fluid as a heterodimer composed of the beta-subunits of inhibins A and B linked by disulfide bond(s) [Ling et al. (1986) Nature, in press]. In this paper we report the isolation of another 24,000 Dalton protein with FSH-releasing activity from porcine follicular fluid, using successive steps of heparin-Sepharose affinity chromatography, gel filtration on Sephacryl S-200, and four steps of reversed-phase HPLC, followed by preparative sodium dodecyl-sulfate-polyacrylamide gel electrophoresis chromatography. Based on the molecular weight of the isolated molecule and its deduced NH2-terminal sequence, we propose that this second FSH-releasing substance present in porcine follicular fluid is a homodimeric protein composed of two beta-subunits of inhibin A joined together by disulfide bond(s). The name homo-activin-A is proposed for this substance.
Publication
Journal: Developmental Biology
July/15/1992
Abstract
Mural and cumulus granulosa cells synthesize hyaluronic acid (HA) and expand in vitro in response to follicle-stimulating hormone and a soluble factor(s) produced by fully grown oocytes. In the present study we examined HA synthesis and extracellular matrix organization by the two cell populations in vivo during the preovulatory period. After injection of human chorionic gonadotropin into pregnant mares' serum gonadotropin-primed animals, a progressive increase in HA synthesis was observed by the cumulus cell-oocyte complex (COC), and by the mural granulosa cells adjacent to the antrum (antral granulosa cells). The outermost layers of mural granulosa cells (peripheral granulosa cells) did not synthesize HA. Net HA synthesis was approximately 4 pg/cell for COCs isolated after full expansion induced either in vivo or in vitro, whereas the total HA content and cell number in the ovulated COC (approximately 11 ng HA and approximately 3000 cells per COC) were about threefold higher than for COCs expanded in vitro (approximately 4 ng HA and approximately 1000 cells per COC). The increased cell content of ovulated COCs appears to be primarily the result of inclusion of proximal mural granulosa cells which synthesize HA in response to the oocyte factor(s) and become incorporated in the expanded COC extracellular matrix mass. Media conditioned by oocytes enclosed in the cumulus cell mass (intact COCs) contained only 10-20% of the HA-stimulatory activity of media conditioned by an equal number of isolated oocytes when tested on mural granulosa cell cultures. Further, HA-stimulatory activity of media conditioned by isolated oocytes was dramatically reduced (approximately 70%) by preincubation for 5 hr with cumulus cells compared to preincubation in the absence of cells. The results suggest that differences in HA synthesis between subregions of membrana granulosa depend on a diffusion gradient of the oocyte factor(s).
Publication
Journal: British Journal of Cancer
March/11/2004
Abstract
A total of 16 premenopausal women with metastatic breast cancer (N=13) or locally advanced primary breast cancer (N=3) were treated with a combination of a gonadotropin-releasing hormone agonist goserelin, and a selective aromatase inhibitor anastrozole. All had previously been treated with goserelin and tamoxifen. In all, 12 patients (75%) achieved objective response or durable stable disease at 6 months, with a median duration of remission of 17+ months (range 6-47 months). Four patients still have clinical benefit. Introduction of goserelin and tamoxifen resulted in an 89% reduction in mean oestradiol levels (pretreatment vs 6 months=224 vs 24 pmol l(-1)) (P<0.0001). Substitution of tamoxifen by anastrozole on progression resulted in a further 76% fall (to 6 pmol l(-1) at 3 months) (P<0.0001). Treatment with goserelin and tamoxifen led to a 90% fall in the mean follicle-stimulating hormone (P<0.001). This was reversed once therapy was changed to goserelin and anastrozole. A similar initial reduction was seen in the mean luteinising hormone levels, but substitution of tamoxifen by anastrozole on progression resulted in no significant change. Goserelin and tamoxifen did not lead to any significant change in testosterone and androstenedione levels. The combined use of goserelin and anastrozole as second-line endocrine therapy produces a significant clinical response of worthwhile duration, with demonstrable endocrine changes, in premenopausal women with advanced breast cancer, and offers them another therapeutic option. Further studies involving more patients and longer follow-up are indicated.
Publication
Journal: Journal of andrology
October/26/2006
Abstract
Inhibin-B is a heterodimeric glycoprotein produced by Sertoli cells. Although inhibin-B levels are low when seminiferous tubules are damaged, studies in normal monkeys reveal that inhibin-B levels also correlate positively with Sertoli cell number. In this study, we measured inhibin-B levels in healthy young adult men aged 18-24 years and in prepubertal boys aged 5-9 years in relation to body mass index (BMI). Inhibin-B levels declined with increasing obesity in young adult men; values were 26% lower in men who were obese compared to normal-weight men. Sex hormone-binding globulin and total testosterone, but not free testosterone, were also lower with increasing BMI; serum follicle-stimulating hormone and luteinizing hormone levels were unaffected by obesity. In prepubertal boys, by contrast, inhibin-B was unaffected by obesity. We propose that reduced levels of inhibin-B indicate that obese men have fewer Sertoli cells than men of normal weight. Moreover, normal values in obese prepubertal boys suggest that the effect of obesity on inhibin-B is established during puberty. Finally, because each Sertoli cell is thought to support a finite number of germ cells, fewer Sertoli cells in obesity may predispose to a lower sperm count in adulthood. We speculate that the escalating prevalence of obesity and insulin resistance among adolescents might negatively influence male reproductive function for the next generation.
Publication
Journal: Contraception
May/12/1981
Abstract
In a group of 5 women on long-term anticonvulsant and oral contraceptive therapy, the plasma ethynylestradiol (EE) concentration on 50 microgram EE daily was 11.1 +/- 4.5 pg/ml. These values were at the lower end of the range found in normal women in this laboratory taking 30 microgram EE daily (6-190 pg/ml). Four women have been studied prospectively for 3 months, over 1 cycle before and 2 cycles during phenobarbital 30 mg b.i.d. therapy. Significant falls in the plasma EE concentration were seen in two women (from 104.8 +/- 13.4 to 37.7 +/- 2.0 pg/ml and from 125.6 +/- 23.8 to 34.8 +/- 6.7 pg/ml p less than 0.01) and breakthrough bleeding was seen in both women. No changes in plasma concentrations of follicle stimulating hormone, progesterone, norethindrone or norgestrel were seen. There was a significant increase in the sex hormone binding globulin capacity from 100.7 +/- 5.8 to 133.3 +/- 1.2 nmoles/1 (p less than 0.05). These changes are consistent with the known microsomal enzyme inducing effect of phenobarbital.
Publication
Journal: Animal Reproduction Science
October/11/2004
Abstract
Productivity in farm species is controlled by many factors, including ovulation rate. In cattle, single ovulations occur most frequently and in sheep (and goats) the number of ova released can range from one to many depending upon the breed, whilst the pig is polyovular. The processes of recruitment and selection determine the number of ovulatory follicles in all these species with FSH and subsequently LH playing major roles. GnRH-agonist models in which endogenous gonadotrophin secretion is suppressed and exogenous LH and/or FSH are administered at specific concentrations in defined patterns, are useful in all three species for elucidating the precise roles of specific hormones in stimulating follicular development. Differences in the hypothalamic-pituitary-ovarian feedback response lead to the differences in the number of ovulatory follicles, as does the pool of antral follicles from which the ovulatory ones are selected. Precocious development of follicles is also associated with more ovulations, as is the case with the Booroola due to the single gene acting through bone morphogenetic proteins (BMPs). It is well established that ovulation rate can also be influenced by exogenous hormone administration and by environmental factors such as nutrition. It has become apparent that these nuritional effects are mediated by a direct action at the level of the ovary, involving insulin, insulin-like growth factors (IGF) I and II and their binding proteins among other factors. These factors can also affect the quality of the oocyte and consequently embryo development and survival. Recently, the regulation of follicular angiogenesis has been shown to be important for the development of ovulatory follicles, particularly vascular endothelial growth factor (VEGF) which is produced primarily by the granulosa cells within the ovary and can be stimulated by gonadotrophins. Administration of VEGF has been shown to stimulate pre-antral follicular growth and increase the number of pre-ovulatory follicles. In summary both extra- and intra-ovarian factors are involved in the control of ovulation rate. Manipulation of the angiogenic process may also provide new opportunities for regulating the quality and number of follicles that ovulate.
Publication
Journal: Journal of Nervous and Mental Disease
December/1/1999
Abstract
This study determined which variables affect women's mood state during the menopausal transition by using six prospective annual assessments of a community-based sample of 354 Australian mid-aged women. Repeated measures multivariate analysis of covariance found that negative mood scores decreased significantly over time and were not related to natural menopausal transition, follicle-stimulating hormone, estradiol, inhibin, age, or education. The magnitude of negative mood was significantly predicted by baseline reporting of premenstrual complaints, negative attitudes to ageing and menopause, and parity of one. During follow-up, the magnitude of negative mood was significantly adversely affected by: prior experience of negative mood, experience of bothersome symptoms, poor self-rated health, negative feelings for partner, no partner, current smoking, low exercise, daily hassles, and high stress. Negative mood was reduced by decreasing symptoms, improving health, positive feelings for partner, gaining a partner, and reducing stress. The menopausal transition had an indirect effect in amplifying the effect of reducing paid work, poor health, and daily hassles.
Publication
Journal: Seminars in Reproductive Medicine
October/3/2007
Abstract
Aging has dramatic effects on the reproductive system in women. Undoubtedly, the most notable changes in the neuroendocrine axis arise from the loss of ovarian function, and thus, the loss of negative feedback on the hypothalamus and pituitary. Progressive decreases in inhibin B and inhibin A result in an early increase in follicle-stimulating hormone (FSH), which initially maintains folliculogenesis and estradiol secretion. Over time, regular ovulatory cycles give way to inconsistent folliculogenesis and ovulation, dramatic swings in estradiol and gonadotropin levels, and markedly irregular cycles. Changes in estrogen positive feedback may contribute to cycle disruption. Studies in younger and older postmenopausal women indicate that changes in the neuroendocrine axis occur with aging that are independent of the changing ovarian hormonal milieu of the menopausal transition. Luteinizing hormone and FSH decrease progressively after the menopause, as does gonadotropin-releasing hormone (GnRH) pulse frequency. However, the overall amount of GnRH increases with aging, consistent with a significant degree of adaptability in the aging brain in women, and suggesting that aging alters pituitary responsiveness to GnRH. Estrogen negative feedback is not altered by aging; studies of the effects of aging on estrogen positive feedback are ongoing.
Publication
Journal: PLoS ONE
January/31/2010
Abstract
The synthesis of the gonadotropin subunits is directed by pulsatile gonadotropin-releasing hormone (GnRH) from the hypothalamus, with the frequency of GnRH pulses governing the differential expression of the common alpha-subunit, luteinizing hormone beta-subunit (LHbeta) and follicle-stimulating hormone beta-subunit (FSHbeta). Three mitogen-activated protein kinases, (MAPKs), ERK1/2, JNK and p38, contribute uniquely and combinatorially to the expression of each of these subunit genes. In this study, using both experimental and computational methods, we found that dual specificity phosphatase regulation of the activity of the three MAPKs through negative feedback is required, and forms the basis for decoding the frequency of pulsatile GnRH. A fourth MAPK, ERK5, was shown also to be activated by GnRH. ERK5 was found to stimulate FSHbeta promoter activity and to increase FSHbeta mRNA levels, as well as enhancing its preference for low GnRH pulse frequencies. The latter is achieved through boosting the ultrasensitive behavior of FSHbeta gene expression by increasing the number of MAPK dependencies, and through modulating the feedforward effects of JNK activation on the GnRH receptor (GnRH-R). Our findings contribute to understanding the role of changing GnRH pulse-frequency in controlling transcription of the pituitary gonadotropins, which comprises a crucial aspect in regulating reproduction. Pulsatile stimuli and oscillating signals are integral to many biological processes, and elucidation of the mechanisms through which the pulsatility is decoded explains how the same stimulant can lead to various outcomes in a single cell.
Publication
Journal: Biology of Reproduction
December/6/1989
Abstract
Twenty-three rhesus monkeys were subjected to 9 days of ovarian hyperstimulation with sequential exposure to human follicle-stimulating hormone (hFSH) and then human luteinizing hormone (hLH) + hFSH. Six animals (26%) did not exhibit sustained, elevated levels of circulating estradiol, primarily due to the occurrence of a premature surge of endogenous LH (n = 4). Seventeen animals (74%) responded with supraphysiologic levels of circulating estradiol (peak value: means = 4480 pg/ml) and received human chorionic gonadotropin (hCG) on Day 10. Oocytes were collected 26 h later by aspiration of large antral follicles. Oocyte quantity (means = 18/animal) and quality (63% mature) were evaluated by in vitro fertilization (IVF), embryonic development, and embryo transfer to foster mothers. Modified conditions for the successful fertilization of oocytes used a Tyrode's augmented (TALP) medium supplemented with 0.3% bovine serum albumin (BSA). Oocytes were inseminated at the metaphase II stage with ejaculated, washed sperm (50 100 x 10(3)/ml) preexposed at ambient temperature to caffeine and dibutyryl cyclic adenosine 3'5'-monophosphate. Successful fertilization ranged from 26% to 75%. In one experiment, 5 of 11 embryos produced by IVF developed in vitro to hatched blastocysts. Embryo freezing employed a propanediol-based protocol and was applied to early cleavage-stage embryos with 100% (5 of 5) post-thaw survival. Two frozen-thawed embryos were transferred transtubally on 3 occasions into rhesus monkeys during the early luteal phase of spontaneous menstrual cycles. One pregnancy resulted, which proceeded normally to the unassisted delivery of a male offspring 170 days after the LH surge. We conclude that this sequential regimen of human gonadotropins provides a cohort of oocytes from rhesus monkeys that will complete meiotic maturation and fertilize in vitro, with embryonic development proceeding in vitro and in vivo. The production of putative antibodies to human gonadotropins, assessed by the presence of Protein A-precipitated hCG binding components in sera, limits the repeated use of monkeys in the hyperstimulation protocol. Nevertheless, this model system should facilitate further studies on oocyte maturation, fertilization, and early embryogenesis in primates.
Publication
Journal: Menopause
December/12/2005
Abstract
OBJECTIVE
To investigate factors associated with the presence, severity, and frequency of hot flushes.
METHODS
A 9-year prospective study of 438 Australian-born women, aged 45 to 55 years and menstruating at baseline. Annual fasting blood collection, physical measurements, and interviews including questions about bothersome hot flushes in previous 2 weeks were performed. A "hot flush index" score was calculated from the product of the severity and frequency data. Data were analyzed using random-effects time-series regression models.
RESULTS
A total of 381 women supplied complete data over the follow-up years. A total of 350 women experienced the menopause transition, of whom 60 (17%) never reported bothersome hot flushes. At baseline, women who reported hot flushes were significantly more likely to have higher negative moods, not be in full- or part-time paid work, smoke, and not report exercising every day. Over the 9-year period of the study, variables significantly associated with reporting bothersome hot flushes were relatively young age (P < 0.001), low exercise levels (P < 0.05), low estradiol levels (P < 0.001), high follicle-stimulating hormone (FSH) levels (P < 0.001), smoking (P < 0.01), being in the late menopause transition (P < 0.001), or being postmenopausal (P < 0.001). In women reporting hot flushes, the hot flush index score increased as their FSH levels increased (P < 0.01), as they entered the late stage of the menopause transition (P < 0.001), and as they became postmenopausal (P < 0.05), and decreased with as their age (P < 0.001) and exercise level (P < 0.05) increased. Between-women analyses found that the hot flush index score was greater in women with higher average FSH levels over time (P < 0.05).
CONCLUSIONS
Menopause status, FSH and estradiol levels, age, exercise level, and smoking status all contributed to the experience of bothersome hot flushes.
Publication
Journal: Annals of the New York Academy of Sciences
April/18/2001
Abstract
During infection, bacterial and viral products, such as bacterial lipopolysaccharide (LPS), cause the release of cytokines from immune cells. These cytokines can reach the brain by several routes. Furthermore, cytokines, such as interleukin-1 (IL-1), are induced in neurons within the brain by systemic injection of LPS. These cytokines determine the pattern of hypothalamic-pituitary secretion that characterizes infection. IL-2, by stimulation of cholinergic neurons, activates neural nitric oxide synthase (nNOS). The nitric oxide (NO) released diffuses into corticotropin-releasing hormone (CRH)-secreting neurons and releases CRH. IL-2 also acts in the pituitary to stimulate adrenocorticotropic hormone (ACTH) secretion. On the other hand, IL-1 alpha blocks the NO-induced release of luteinizing hormone-releasing hormone (LHRH) from LHRH neurons, thereby blocking pulsatile LH but not follicle-stimulating hormone (FSH) release and also inhibiting sex behavior that is induced by LHRH. IL-1 alpha and granulocyte macrophage colony-stimulating factor (GMCSF) block the response of the LHRH terminals to NO. The mechanism of action of GMCSF to inhibit LHRH release is as follows. It acts on its receptors on gamma-aminobutyric acid (GABA)ergic neurons to stimulate GABA release. GABA acts on GABAa receptors on the LHRH neuronal terminal to block NOergic stimulation of LHRH release. IL-1 alpha inhibits growth hormone (GH) release by inhibiting GH-releasing hormone (GHRH) release, which is mediated by NO, and stimulating somatostatin release, also mediated by NO. IL-1 alpha-induced stimulation of PRL release is also mediated by intrahypothlamic action of NO, which inhibits release of the PRL-inhibiting hormone dopamine. The actions of NO are brought about by its combined activation of guanylate cyclase-liberating cyclic guanosine monophosphate (cGMP) and activation of cyclooxygenase (COX) and lipoxygenase (LOX) with liberation of prostaglandin E2 and leukotrienes, respectively. Thus, NO plays a key role in inducing the changes in release of hypothalamic peptides induced in infection by cytokines. Cytokines, such as IL-1 beta, also act in the anterior pituitary gland, at least in part via induction of inducible NOS. The NO produced inhibits release of ACTH. The adipocyte hormone leptin, a member of the cytokine family, has largely opposite actions to those of the proinflammatory cytokines, stimulating the release of FSHRF and LHRH from the hypothalamus and FSH and LH from the pituitary directly by NO.
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