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Publication
Journal: The Lancet
July/18/1982
Abstract
Four premenopausal women with metastatic breast cancer were treated with a potent luteinising-hormone-releasing-hormone (LHRH) analogue as a single first-line agent. Buserelin (6-D-ser-(but(-LHRH-(1-9)-ethylamide) was given in very high dose intravenously and then intranasally; ovarian function did not decrease within 1-2 weeks, but after this period low to very low (postmenopausal) plasma oestradiol levels were reached in all patients, accompanied by flushes. Two patients, however, subsequently showed transient peaks of plasma oestradiol, probably due to a persistent follicle, which lasted for some weeks without a rise in plasma luteinising hormone, follicle-stimulating hormone, or progesterone. In two patients there was a significant change in the tumour, whereas in the other two patients there was remarkable improvement.
Publication
Journal: Endocrinology
February/26/2007
Abstract
FSH is produced by the pituitary gonadotrope to regulate gametogenesis. Production of the beta-subunit of FSH is the rate-limiting step in FSH synthesis, and a number of peptide and steroid hormones within the reproductive axis have been found to regulate transcription of the FSH beta-subunit gene. Although both activin and glucocorticoids are notable regulators of FSHbeta by themselves, we find that cotreatment results in a synergistic interaction on the mouse FSHbeta promoter at the level of the gonadotrope using transient transfection of a reporter gene into the LbetaT2 immortalized gonadotrope-derived cell line. This synergistic interaction is specific to FSHbeta, because only additive effects of these two hormones are observed on LH beta-subunit, GnRH receptor, and mouse mammary tumor virus gene expression. Components of both activin and glucocorticoid signaling are found to be necessary for synergy, and there are specific cis elements on the mouse FSHbeta promoter that contribute to the synergistic response as well. We also identify novel activin-responsive regions in the mouse FSHbeta promoter and find that the -120 site can bind Smad2/3 in vitro. In addition, the glucocorticoid receptor and Smad3 are sufficient to confer a striking synergy with glucocorticoids on the mouse FSHbeta promoter. Our studies provide the first evidence of a synergistic interaction between activin and glucocorticoids within the gonadotrope cell and demonstrate that this synergy can occur directly at the level of the mouse FSHbeta promoter.
Publication
Journal: Biochemical and Biophysical Research Communications
December/19/2004
Abstract
Epiregulin and amphiregulin are growth factors involved in cancer development, but their potential role in signaling in the gonads is still obscure. We report here that basal expression of these growth factors is evident in human granulosa cells obtained from women treated for in vitro fertilization, when examined by RT-PCR using RNA isolated from primary cultures of ovarian granulosa cells. Expression of these factors was elevated concomitantly with elevation of progesterone production in these cells upon stimulation with luteinizing hormone (LH), and to a lesser extent with follicle stimulating hormone (FSH), both essential stimulants for ovulation and luteinization. Epiregulin and amphiregulin gene expression was dose- and time-dependent when measured subsequent to LH stimulation. Moreover, forskolin, which activates adenylate cyclase, was as efficient as LH in stimulating expression of these growth factors. It is suggested that upregulation of the epiregulin and amphiregulin expression is part of the signal transduction pathway which leads to ovulation and luteinization in the human ovary.
Publication
Journal: Medicine and Science in Sports and Exercise
October/14/1986
Abstract
The increase in serum testosterone levels generally observed with intense, short-term exercise remains unexplained since most investigators have not reported any increase in the levels of luteinizing hormone, the pituitary glycoprotein most responsible for testicular steroidogenesis. Hemoconcentration and decreased metabolic clearance have been suggested as mechanisms to explain the exercise-associated testosterone increase. Such non-specific mechanisms should apply to other steroid hormones as well as to testosterone. To investigate whether the exercise-induced changes in other steroid hormones were similar to that of testosterone, we measured serum levels of testosterone, androstenedione, dehydroepiandrosterone, and cortisol as well as gonadotropins, luteinizing hormone and follicle-stimulating hormone, and prolactin at 5-15 min intervals throughout progressive maximal intensity exercise on a cycle ergometer. Significant increases were observed with all hormones with exercise. The increase in serum testosterone began prior to exercise, peaked at 20 min after the beginning of exercise, and fell to baseline within 10 min. The serum luteinizing hormone increase was synchronous with that of testosterone, suggesting that gonadotropin stimulation was not responsible for the testosterone increment. The increments in serum cortisol, androstenedione, dehydroepiandrosterone, and prolactin levels were simultaneous but began 25-30 min after that of testosterone in all subjects. These findings, therefore, suggest that, contrary to previous evidence, the exercise-associated increase in serum testosterone results predominantly from a specific mechanism, presumably involving increased testicular production without gonadotropin stimulation.
Publication
Journal: FEBS Letters
December/8/2002
Abstract
The gap junctional intercellular communication mediated by Cx43 plays indispensable roles in both germ line development and postnatal folliculogenesis. In this study, we focused on the effect of follicle-stimulating hormone (FSH) on the Cx43 protein in rat primary granulosa cells and found that FSH stimulation elevated the phosphorylation in addition to the protein level of Cx43. Serine residues in the carboxyl-terminal region were exclusively phosphorylated in this system and we identified Ser365, Ser368, Ser369 and Ser373 as major phosphorylation sites by FSH stimulation. A Cx43 variant containing mutations at all these serine residues was found to severely reduce dye transfer activity when assayed in HeLa cells. The present study revealed a novel regulatory mechanism of Cx43-mediated gap junctional intercellular communication through phosphorylation in the carboxyl-terminus.
Publication
Journal: Journal of Neurosurgery
February/25/1991
Abstract
In a review of autopsy material from two centers, 20 pituitary glands were found containing multiple adenomas. In total, 44 adenomas were identified histologically; 16 glands contained double tumors and in four glands triple adenomas were found. Size was measured in 30 tumors, all of which were microadenomas. Thirty-four adenomas were located in the lateral wings and 10 lay in the median wedge. Forty-one tumors were chromophobic and three were basophilic. Immunocytochemical analysis of the 44 tumors demonstrated the presence of prolactin in 11, adrenocorticotropic hormone in three, growth hormone in one, and alpha-subunit as well as follicle-stimulating hormone and luteinizing hormone in one. Of the 20 patients studied, there were 11 men and nine women, with an average age of 69 years. All patients died from various nonendocrine causes. With the exception of one patient who appeared mildly acromegalic, no correlation was observed between pituitary morphology and clinical data. This study found a 10.4% frequency of adenomas in pituitaries studied randomly at autopsy. Multiple tumors were encountered in 0.9% of cases. Despite its low frequency, adenoma multiplicity may underlie surgical failure in cases in which one adenoma is removed and the other is left behind.
Publication
Journal: Journal of Clinical Investigation
December/22/1987
Abstract
Approximately 25% of patients with pituitary adenomas have no clinical or biochemical evidence for excess hormone secretion and are classified as having null cell or nonfunctioning adenomas. To characterize the cell type of these tumors, we analyzed pituitary hormone gene expression in clinically nonfunctioning pituitary adenomas using specific oligonucleotide probes for the messenger (m)RNAs encoding growth hormone, prolactin, ACTH, and the glycoprotein hormone subunits, alpha, luteinizing hormone (LH)beta, follicle-stimulating hormone (FSH)beta, and thyroid-stimulating hormone (TSH)beta. Expression of one or more of the anterior pituitary hormone genes was found in 12/14 (86%) of the patients with clinically classified nonfunctioning adenomas. Expression of one or more of the glycoprotein hormone genes (alpha, LH beta, FSH beta, TSH beta) was identified most commonly (79%) with expression of multiple beta-subunit genes in many cases. Expression of alpha-subunit mRNA was found in each of the adenomas from patients expressing one of the beta-subunit mRNAs and in three patients with no detectable beta-subunit mRNA. Although FSH beta and LH beta mRNAs were found with similar frequencies in nonfunctioning adenomas, expression of FSH beta mRNA was generally much more abundant. TSH beta mRNA was detected in only one adenoma. The levels of glycoprotein hormone subunit mRNAs were variable in different adenomas, but the lengths of the mRNAs and transcriptional start sites for the alpha- and beta-subunit genes were the same in the pituitary adenomas and in normal pituitary. Growth hormone and prolactin gene expression were not observed in the nonfunctioning adenomas, but ACTH mRNA was found in a single case. Immunohistochemistry of the adenomas confirmed production of one or more pituitary hormones in 13/14 (93%) nonfunctioning tumors, with a distribution of hormone production similar to that of the hormone mRNAs. These data indicate that pituitary adenomas originating from cells producing glycoprotein hormones are common, but are difficult to recognize clinically because of the absence of characteristic endocrine syndromes and defective hormone biosynthesis and secretion.
Publication
Journal: FASEB Journal
December/30/2008
Abstract
The cytochrome P450 (CYP) enzymes participate in a wide range of biochemical functions, including metabolism of arachidonic acid and steroid hormones. Mouse CYP2J5 is abundant in the kidney where its products, the cis-epoxyeicosatrienoic acids (EETs), modulate sodium transport and vascular tone. To define the physiological role of CYP2J5 in the kidney, knockout mice were generated using a conventional gene targeting approach. Cyp2j5 (-/-) mice develop normally and exhibit no overt renal pathology. While renal EET biosynthesis was apparently unaffected by the absence of CYP2J5, deficiency of this CYP in female mice was associated with increased blood pressure, enhanced proximal tubular transport rates, and exaggerated afferent arteriolar responses to angiotensin II and endothelin I. Interestingly, plasma 17beta-estradiol levels were reduced in female Cyp2j5 (-/-) mice and estrogen replacement restored blood pressure and vascular responsiveness to normal levels. There was no evidence of enhanced estrogen metabolism, or altered expression or activities of steroidogenic enzymes in female Cyp2j5 (-/-) mice, but their plasma levels of luteinizing hormone and follicle stimulating hormone were inappropriately low. Together, our findings illustrate a sex-specific role for CYP2J5 in regulation of blood pressure, proximal tubular transport, and afferent arteriolar responsiveness via an estrogen-dependent mechanism.
Publication
Journal: The Lancet
December/28/1977
Abstract
In eight impotent haemodialysed men with low plasma-zinc levels sexual function, including potency, frequency of intercourse, libido, and plasma testosterone, follicle-stimulating hormone, and luteinising hormone levels, was determined before and after therapy with zinc (four patients) or placebo (four patients). Dialytic administration of zinc strikingly improved potency in all patients and raised the plasma-testosterone to normal in the two with low pretreatment plasma-testosterone levels. Placebo did not improve sexual function in any patient. Zinc deficiency is a reversible cause of gonadal dysfunction in uraemia.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
April/11/2001
Abstract
Studies of sex steroid regulation of gonadotropin secretion in the human male have focused primarily on the respective site(s) of negative feedback of testosterone (T) and estradiol (E(2)). The use of pharmacological doses of sex steroids in these studies has precluded conclusions about the relative roles of T and E(2) in gonadotropin feedback. Thus, the aims of the present study were to 1) determine the relative contributions of T vs. E(2) to the sex steroid component of gonadotropin regulation, and 2) distinguish the feedback effects of T that that are direct (i.e. mediated by the androgen receptor) vs. indirect (mediated by aromatization to E(2)). Two experimental interventions were used: 1) inhibition of aromatization by a selective aromatase inhibitor to examine the impact of selective E(2) withdrawal; and 2) acute medical castration to examine the effect of ablating both T and E(2). Sixteen normal (NL) men (mean age, 30.5 +/- 2.2 yr) were studied. Nine NL subjects were treated with the aromatase inhibitor, anastrozole (10 mg, orally, daily, for 5 days). Twelve NL men underwent medical castration with ketoconazole (1-g loading dose followed by 400 mg, orally, four times a day for 5 days). Ketoconazole-treated subjects received concomitant treatment with dexamethasone (0.5 mg twice daily) to prevent the development of adrenal insufficiency. Single blood samples were drawn daily between 0800-1000 h. To ensure that dexamethasone was not altering the gonadotropin response to sex steroid ablation by a direct pituitary effect, five GnRH-deficient men (mean age, 37.6 +/- 3.9 yr) underwent GnRH dose-response studies at baseline and after treatment with dexamethasone (0.5 mg twice daily). Aromatase blockade caused significant lowering of E(2) (33 +/- 3 to 14 +/- 1 pg/mL; P: < 0.0005) with a corresponding increase in T levels (563 +/- 42 to 817 +/- 81 ng/dL; P: < 0.05). Treatment with ketoconazole resulted in equivalent suppression of E(2) (41 +/- 4 to 14 +/- 1 pg/mL; P: < 0.0005), but also induced castrate levels of T (491 +/- 28 to 40 +/- 3 ng/dL; P: < 0.0005). Both treatment regimens were associated with a significant increase in gonadotropin levels. For LH, the percent increase in serum levels after castration was almost 3-fold greater than that seen after selective E(2) withdrawal (275 +/- 23% with ketoconazole vs. 95.6 +/- 21% with anastrozole; P: < 0.005). Despite the divergent changes in T levels with these two maneuvers (a marked decrease after ketoconazole and a significant increase with anastrozole), the percent rise in FSH levels was similar in the two protocols (91 +/- 6% vs. 71 +/- 7%, respectively; P: = NS). Inhibin B levels were unchanged after selective E(2) withdrawal (156 +/- 23 vs. 176 +/- 19 pg/mL), but decreased slightly with ketoconazole (156 +/- 15 to 131 +/- 11 pg/mL; P: < 0.05). In contrast to the effects of glucocorticoid administration on gonadotropin secretion in women, no significant changes were observed in the GnRH-deficient men treated with dexamethasone in terms of mean LH levels (19.8 +/- 3.2 vs. 23.3 +/- 5.4 IU/L), mean LH pulse amplitude after GnRH (16.0 +/- 2.5 vs. 19.0 +/- 5.1 IU/L), or mean FSH levels (8.0 +/- 1.9 vs. 9.2 +/- 2.4 IU/L, pre vs. post). These studies provide evidence of differential regulation of gonadotropin secretion by T in the human male. T exerts both direct and indirect feedback on LH secretion, whereas its effects on FSH appear to be mediated largely by aromatization to E(2). From these data we conclude that in terms of sex steroid feedback, E(2) is the predominant regulator of FSH secretion in the human male.
Publication
Journal: Journal of Neuroendocrinology
July/31/2007
Abstract
In the male monkey, luteinising hormone (LH) secretion is regulated by a negative feedback action of testicular testosterone that is exerted indirectly at the hypothalamic level to decelerate pulsatile gonadotrophin-releasing hormone release (GnRH). The purpose of the present experiment was to investigate whether the kisspeptin-G protein-coupled receptor 54 (GPR54) signalling pathway is involved in mediating the action of testosterone to suppress GnRH release in the monkey, as has been indicated by studies of nonprimates. To this end, 12 castrated adult male rhesus monkeys were implanted with either testosterone containing or empty Silastic capsules. Testosterone treatment produced a square wave increment in circulating testosterone levels within the physiologic range. After suppression of LH and follicle-stimulating hormone secretion was established at 5-6 weeks of testosterone exposure, the animals were killed and expression of the genes encoding for kisspeptin, GPR54 and GnRH determined in the mediobasal hypothalamus and preoptic area of both treated and control animals using RNase protection assays. The suppression in pituitary gonadotrophin secretion was associated with a reduction in kisspeptin mRNA levels in the mediobasal hypothalamus, but not the preoptic area. GPR54 mRNA levels, on the other hand, were not influenced by testosterone treatment. These results are consistent with those previously reported for the rodent, and suggest that the neurobiology of the negative feedback action of testicular testosterone on LH secretion in the monkey, a representative higher primate, may be mediated by kisspeptinergic neurones upstream to the GnRH network.
Publication
Journal: Molecular Endocrinology
June/8/2003
Abstract
Spermatogenesis requires the presence of functional somatic Sertoli cells in the seminiferous tubules of the testis. Sertoli cells provide support and factors necessary for the successful progression of germ cells into spermatozoa. Sertoli cells are regulated to a large degree by the glycoprotein hormone FSH, which is required for the testis to acquire full size and spermatogenic capacity. Signaling events initiated by the binding of FSH to its receptor lead to an alteration of Sertoli cell gene expression. To characterize the changes in gene expression in FSH-treated Sertoli cells, we used the mRNA from these cells to screen Affymetrix U34A rat GeneChip oligonucleotide microarrays. Sertoli cells from 20-d-old rats were cultured in the presence of 25 ng/ml ovine FSH. At 0, 2, 4, 8, and 24 h after the addition of FSH, total RNA was purified and used to prepare biotinylated target, which was hybridized to the U34A rat microarray containing approximately 9000 rat genes. Analysis identified 100-300 transcripts at each time point that were up-regulated or down-regulated by 2-fold or greater. Genes previously reported to be FSH or cAMP regulated in rat Sertoli cells were identified, in addition to numerous genes not reported to be expressed or FSH regulated in Sertoli cells. The expression patterns of five of these genes, encoding nerve growth factor inducible gene B, PRL-1, PC3 nerve growth factor-inducible antiproliferative putative secreted protein, diacylglycerol acyltransferase, and an expressed sequence tag, in FSH- and N,O'-dibutyryl cAMP-treated rat Sertoli cells were confirmed and characterized by Northern blot analysis. Thus, we have begun to define the transcriptome induced and repressed by FSH in rat Sertoli cells, and we have generated datasets of genes available for further analysis in regard to spermatogenesis and Sertoli cell signaling.
Publication
Journal: Obesity
February/14/2007
Abstract
OBJECTIVE
To examine whether obesity and insulin resistance have an independent effect on the gonadotropin, estradiol, and inhibin B serum levels and follicle count in the early follicular phase of fertile women with a wide range of BMI and without signs of hyperandrogenism.
METHODS
Twenty-two overweight and obese (BMI>> or =25.0 kg/m(2)) women and 10 normal-weight (BMI <25.0 kg/m(2)) women, all having apparently normal fertility, were studied. Serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, inhibin B, and insulin, level of insulin resistance (estimated by homeostasis model assessment for insulin resistance), and follicle count were measured during the early follicular phase (Days 2 to 5 of the menstrual cycle).
RESULTS
Overweight women showed lower FSH (p < 0.001), LH (p < 0.001), and inhibin B (p < 0.05) levels compared with normal-weight women, whereas estradiol concentrations and follicle count were not significantly different between the two groups. When normal-weight and overweight women were examined as a group and multiple regression analyses were performed, estradiol showed a negative association with BMI (or waist circumference) (p < 0.05) and a positive correlation with LH (p < 0.05) and FSH (p < 0.05); inhibin B maintained a positive association only with estradiol (p < 0.05); and FSH and LH showed a negative correlation with BMI (or waist circumference) (p < 0.001 and p < 0.01, respectively).
CONCLUSIONS
Overweight and obese fertile women have lower FSH, LH, inhibin B, and estradiol levels in the early follicular phase, with a possible direct inhibitory effect of body mass on gonadotropin and estradiol production, independently of age, insulin (concentrations and sensitivity), and other hormones. By contrast, the number of ovary follicles does not seem to be influenced by insulin and body mass in these patients.
Publication
Journal: Obstetrics and Gynecology
June/29/2005
Abstract
OBJECTIVE
Several clinical studies suggest that black cohosh may be effective in climacteric complaints. However, evidence of its efficacy based on current quality standards has been limited.
METHODS
This randomized, multicenter, double-blind clinical trial compared the efficacy and tolerability of the isopropanolic black cohosh extract in the treatment of climacteric complaints compared with placebo. A total of 304 patients were randomly allocated to receive tablets corresponding to 40 mg drug or matching placebo daily for 12 weeks. The primary efficacy measure was the change from baseline on the Menopause Rating Scale I; secondary measures included changes in its subscores and safety variables.
RESULTS
Patient groups did not differ in baseline characteristics. The isopropanolic black cohosh extract was more effective than placebo (P < .001) depending on time from symptom onset (P = .014) and follicle-stimulating hormone level (P = .011). The effect size was 0.03 to 0.05 Menopause Rating Scale units which is similar to recent hormone replacement therapy study results (0.036 Menopause Rating Scale units) and may therefore be considered clinically relevant. Women in the early climacteric phase benefited more than in the late phase. The hot flush subscore was the most effective measure of the isopropanolic black cohosh extract's efficacy. There were no relevant group differences in adverse events, laboratory findings, or tolerability.
CONCLUSIONS
This isopropanolic extract of black cohosh root stock is effective in relieving climacteric symptoms, especially in early climacteric women.
Publication
Journal: Endocrinology
May/22/1995
Abstract
Activin markedly stimulates FSH beta messenger RNA (mRNA) levels in rat pituitary cells. Nonetheless, the molecular mechanisms through which activin enhances FSH beta gene expression are not clear. To assess the role of transcriptional activation in activin stimulation, we first transfected two -2300FSH beta Luc constructs into primary pituitary cells and treated them with activin in plated culture and perifusion. Basal expression of the constructs was low, and no activin response was observed. These results suggested that additional FSH beta sequences are required for basal expression or that the effects of activin are not transcriptional. An alternative approach for measuring transcriptional responses was developed based upon changes in the levels of FSH beta primary transcripts (FSH beta-PT; newly transcribed mRNAs that still contain the first intron) after activin (3 ng/ml) stimulation of perifused rat pituitary cells. An increase in FSH beta-PT was observed after 30 min of activin stimulation, preceding the first observable rise in mature FSH beta mRNA. Levels of FSH beta-PT peaked between 1-2 h, then fell to a lower level (28% of maximal) at 4 h, which was maintained through 10 h of activin stimulation (36% of maximal at 10 h). Mature FSH beta mRNA levels peaked between 2-4 h, which is after the increase in FSH beta-PT, and fell more gradually between 4-10 h of stimulation (56% of maximal at 10 h). Unstimulated levels of mature mRNA and FSH beta-PT did not vary significantly over the course of the experiments. Cotreatment with the transcriptional inhibitor actinomycin-D (2 microM) blocked activin stimulation of both FSH beta-PT and FSH beta mRNA, confirming the transcriptional basis for these events. In summary, we have documented rapid and sequential increases in FSH beta-PT and mature FSH beta mRNAs after activin stimulation, which are prevented by transcriptional blockade. These data provide evidence that the increase in FSH beta mRNA levels after activin treatment are at least partly due to transcriptional activation of the FSH beta gene.
Publication
Journal: Fertility and Sterility
April/22/1993
Abstract
OBJECTIVE
To isolate intact preantral follicles from the human ovary for in vitro studies.
METHODS
Premenopausal human ovary was digested by a mixture of collagenase and deoxyribonuclease (DNase) for 1 hour at 37 degrees C and for 36 hour at 4 degrees C. Intact preantral follicles at classes 1 and 2 were isolated and cultured for up to 120 hours in a serum-free Dulbecco's modified Eagle's medium (GIBCO, Grand Island, NY) with ITS+ (insulin, transferrin, selenium, linoleic acid, and bovine serum albumin; Collaborative Research, Bedford, MA) with or without FSH. Follicular DNA synthesis was measured by [3H]thymidine incorporation, whereas steroidogenic capacity was assessed by P, androstenedione (A), and 17 beta-E2 RIA. The morphology of long-term cultured follicles was studied by routine histologic procedure.
RESULTS
A large number of intact, preantral follicles was efficiently dissociated from a portion of ovary. Morphologically, follicles were healthy and did not have any thecal layer. Follicle-stimulating hormone, in vitro, induced follicular DNA synthesis by 24 hours and antrum formation in class 2 follicles after 120 hours. Both class 1 and 2 follicles were able to produce a small basal amount of P and A, but they did not produce any measurable E2. However, both classes synthesized increasing amounts of P, A, and E2 after FSH exposure.
CONCLUSIONS
This is a first report of a successful enzymatic isolation of human preantral follicles and their long-term culture in vitro. The growth and differentiation of preantral follicles by FSH clearly indicate the importance of FSH in human follicular development. These results provide an opportunity for quantitative studies on factors regulating folliculogenesis in the human and a novel future direction for human IVF.
Publication
Journal: Arteriosclerosis, Thrombosis, and Vascular Biology
April/25/2001
Abstract
-Postmenopausal hormone replacement therapy (HRT) is associated with low cardiovascular morbidity and mortality in epidemiological studies. Yet, no randomized trial has examined whether HRT is effective for prevention of coronary heart disease (CHD) in women with increased risk. The objective of this study was to determine whether HRT can slow progression of atherosclerosis, measured as intima-media thickness (IMT) in carotid arteries. Carotid IMT is an appropriate intermediate end point to investigate clinically relevant effects on atherogenesis. This randomized, controlled, observer-blind, clinical, single-center trial enrolled 321 healthy postmenopausal women with increased IMT in>>/=1 segment of the carotid arteries. For a period of 48 weeks, subjects received either 1 mg/d 17ss-estradiol continuously plus 0.025 mg gestodene for 12 days every month (standard-progestin group), or 1 mg 17ss-estradiol plus 0.025 mg gestodene for 12 days every third month (low-progestin group), or no HRT. Maximum IMT in 6 carotid artery segments (common, bifurcation, and internal, both sides) was measured by B-mode ultrasound before and after intervention. HRT did not slow IMT progression in carotid arteries. Mean maximum IMT in the carotid arteries increased by 0.02+/-0.05 mm in the no HRT group and by 0.03+/-0.05 and 0.03+/-0.05 mm, respectively, in the HRT groups (P:>0.2). HRT significantly decreased LDL cholesterol, fibrinogen, and follicle-stimulating hormone. In conclusion, 1 year of HRT was not effective in slowing progression of subclinical atherosclerosis in postmenopausal women at increased risk.
Publication
Journal: Menopause
October/7/2009
Abstract
OBJECTIVE
The aim of this study was to examine the relationship between perimenopausal memory complaints and performance on objective neuropsychological tests. A secondary aim was to determine if putative deficits are related to other relevant factors, such as hormone levels, mood state, or sleep quality.
METHODS
Twenty-four perimenopausal women were enrolled. Participants completed questionnaires assessing mood, anxiety, menopausal symptoms, health, and subjective memory function. They also underwent comprehensive cognitive testing, which included measures of attention, working memory, verbal memory, verbal fluency, visuospatial skill, and fine motor dexterity. We obtained serum estradiol and follicle-stimulating hormone levels on the day of testing.
RESULTS
We found no association between memory complaints and performance on tests of retentive memory. However, memory complaints were associated with poorer memory encoding and increased depressive symptoms. Regression analyses revealed that memory complaints were best predicted by depressive symptoms, whereas encoding performance was predicted by depressive symptoms and estrogen level. Women with significant memory complaints performed worse on tests of encoding, after controlling for depression and sleep disturbance.
CONCLUSIONS
These results suggest a complex relationship between mood, memory, and hormones that may underlie perimenopausal memory complaints. Furthermore, they suggest that some women may be particularly vulnerable to the subjective experience of memory problems and relative decreases in attentionally mediated cognitive function.
Publication
Journal: Biology of Reproduction
August/6/2000
Abstract
Sertoli cells express functional receptors for FSH, one of the two pituitary hormones that regulate spermatogenesis in mammals. We recently produced genetic mutant (FORKO) mice that lack FSH receptor, in order to examine the effects on testicular function and fertility. Mutant males exhibited weight loss of testis, epididymis, and seminal vesicle as well as low levels of testosterone. Except for reduced seminiferous tubular diameter, no gross changes were apparent upon histological examination. Analysis of testicular germ cells by flow cytometry revealed a significant increase in the percentage of 2C cells (spermatogonia and non-germ cells) and a significant decrease in the percentage of HC cells (elongated spermatids) of FORKO males. The absolute number of homogenization-resistant elongated spermatids was also significantly reduced in the mutant males. A 2-fold increase in c-kit-positive 2C cells was recorded in the mutant males. Elongated spermatids of FORKO males showed a dramatic increase in propidium iodide binding suggesting reduced nuclear compaction. The increase in size of the sperm head in mutants, as well as susceptibility to dithiothreitol-induced decondensation, suggests the inadequate condensation of sperm chromatin. Sperm chromatin structure assay, a technique that reflects DNA stability, revealed that sperm from FORKO males are susceptible to acid denaturation, indicating the poor quality of sperm. These data allow us to conclude that genetic disruption of FSH receptor signaling in the rodent induces major changes that might contribute to reduced fertility.
Publication
Journal: Psychosomatic Medicine
November/15/2012
Abstract
OBJECTIVE
The neurobiological mechanisms of structural brain abnormalities in patients with anorexia nervosa (AN) remain poorly understood. In particular, little is known about the changes in and the recovery of gray matter (GM) volumes after weight gain and the relation to hormonal normalization in adolescent patients with AN.
METHODS
Nineteen female patients aged 12 to 17 years were assessed using magnetic resonance imaging at the time of admission to the hospital (T1) and after weight recovery (T2). Patients were compared with typically developing girls matched for age and intelligence quotient. Structural brain images were analyzed using a voxel-based morphometric approach. Circulating levels of cortisol and gonadotropins were assessed in blood samples.
RESULTS
Compared with controls, patients with AN showed reduced GM in several brain regions along the cortical midline, reaching from the occipital cortex to the medial frontal areas. These GM reductions were mostly reversible at T1. Patients showed a GM increase from T1 to T2 along the cortical midline and in the occipital, temporal, parietal, and frontal lobes. GM increases at T2 correlated inversely with cortisol levels at T1 and positively with weight gain at T2. The strongest associations between regional GM increase and weight gain were found in the cerebellum. In addition, increases in GM volumes at T2 in the thalamus, hippocampus, and amygdala were associated with increases in follicle-stimulating hormone.
CONCLUSIONS
Our data suggest that brain alterations in adolescents with acute AN are mostly reversible at T1 and that GM recovery in specific brain regions is associated with weight and hormonal normalization.
Publication
Journal: Developmental Biology
July/9/2002
Abstract
The second messenger cyclic adenosine 5'monophosphate (cAMP) has been implicated in controlling meiotic maturation. To date, there have been no direct measurements of cAMP in living mammalian oocytes. Here, we have used the fluorescently labelled cAMP-dependent protein kinase A (PKA), FlCRhR, to monitor cAMP in mouse oocytes. In cumulus-enclosed oocytes, follicle-stimulating hormone (FSH) stimulated an increase in the oocyte [cAMP] that was prevented by using the gap junction inhibitor, carbenoxolone. The FSH-induced increase in oocyte [cAMP] was suppressed in a time-dependent manner by prior exposure to ATP, while epidermal growth factor had no effect on basal or stimulated levels of cAMP. Finally, using confocal microscopy, we show that the regulatory and catalytic subunits of the microinjected PKA are distributed in a punctate manner with a stronger accumulation in the perinuclear region. On an increase in [cAMP], in response to phosphodiesterase inhibition or FSH, the catalytic subunit diffused throughout the cytoplasm and germinal vesicle, while the regulatory subunit remained anchored. These experiments show that increases in cAMP in ovarian somatic cells are communicated via gap junctions to the oocyte, where it can lead to a redistribution of the catalytic subunit of PKA.
Publication
Journal: Menopause
April/15/2015
Abstract
OBJECTIVE
This study aims to estimate the risk of hot flashes relative to natural menopause and to evaluate the associations of hormone levels, behavioral variables, and demographic variables with the risk of hot flashes after menopause.
METHODS
We performed annual assessment of 255 women who were premenopausal at baseline and reached natural menopause within 16 years of follow-up.
RESULTS
The prevalence of moderate/severe hot flashes increased in each premenopausal year, reaching a peak of 46% in the first 2 years after the final menstrual period (FMP). Hot flashes decreased slowly after menopause and did not return to premenopausal levels until 9 years after the FMP. The mean (SD) duration of moderate/severe hot flashes after the FMP was 4.6 (2.9) years (for any hot flashes, 4.9 [3.1] y). One third of women at 10 years or more after menopause continued to experience moderate/severe hot flashes. African-American women (obese and nonobese) and obese white women had significantly greater risks of hot flashes compared with nonobese white women (interaction, P = 0.01). In multivariable analysis, increasing follicle-stimulating hormone levels before the FMP (P < 0.001), decreasing estradiol (odds ratio, 0.87; 95% CI, 0.78-0.96; P = 0.008), and increasing anxiety (odds ratio, 1.05; 95% CI, 1.03-1.06; P < 0.001) were significant risk factors for hot flashes, whereas higher education levels were protective (odds ratio, 0.66; 95% CI, 0.47-0.91; P = 0.011).
CONCLUSIONS
Moderate/severe hot flashes continue, on average, for nearly 5 years after menopause; more than one third of women observed for 10 years or more after menopause have moderate/severe hot flashes. Continuation of hot flashes for more than 5 years after menopause underscores the importance of determining individual risks/benefits when selecting hormone or nonhormone therapy for menopausal symptoms.
Publication
Journal: Fertility and Sterility
September/6/1990
Abstract
Prior studies have demonstrated that gonadotropin stimulation quality and pregnancy rates are better in in vitro fertilization (IVF) patients with low basal cycle day 3 follicle-stimulating hormone (FSH) levels. The records of 81 patients who had undergone three or more IVF attempts during a 2-year period were studied to determine the degree and potential impact of intercycle variability in basal FSH concentrations. The mean of the individual standard deviations for all 81 patients was 4.2 +/- 0.4 mIU/mL. However, the patients with a mean basal FSH of less than 15 mIU/mL had a mean deviation of only 2.6 +/- 0.2 mIU/mL, whereas those with a mean basal FSH of greater than or equal to 15 mIU/mL had a mean deviation of 7.3 +/- 0.7 mIU/mL. Intercycle variability in basal FSH values did not predict changes in ovarian response to gonadotropin stimulation and thus may not be used to select an optimal cycle in which to stimulate an individual patient. Furthermore, patients with large intercycle variation responded poorly to gonadotropin stimulation independent of their basal FSH concentration. This information allows more precise counseling of patients regarding their appropriateness for assisted reproduction.
Publication
Journal: FEBS Letters
October/21/2013
Abstract
Forkhead L2 (Foxl2) is expressed in ovarian granulosa cells and participates in steroidogenesis by transcriptionally regulating target genes such as steroidogenic acute regulatory protein (StAR) and CYP19A1. In this study, a direct link between microRNA-133b (miR-133b) and Foxl2-mediated estradiol release in granulosa cells was established. miR-133b was involved in follicle-stimulating hormone (FSH)-induced estrogen production. Luciferase assays confirmed that miR-133b was bound to the 3' untranslated region (3'UTR) of Foxl2 mRNA. Consistent with this finding, miR-133b overexpression reduced the Foxl2 levels. Furthermore, miR-133b inhibited Foxl2 binding to the StAR and CYP19A1 promoter sequences. These results demonstrate that miR-133b down-regulates Foxl2 expression in granulosa cells by directly targeting the 3'UTR, thus inhibiting the Foxl2-mediated transcriptional repression of StAR and CYP19A1to promote estradiol production.
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