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Publication
Journal: Journal of andrology
July/28/2009
Abstract
Experimental animal studies have demonstrated that exposure to some phthalates may be associated with altered endocrine function and adverse effects on male reproductive development and function, but human studies are limited. In the present study, urine and serum samples were collected from 425 men recruited through a US infertility clinic. Urinary concentrations of mono(2-ethylhexyl) phthalate (MEHP), the hydrolytic metabolite of di(2-ethylhexyl) phthalate (DEHP), and other phthalate monoester metabolites were measured, along with serum levels of testosterone, estradiol, sex hormone-binding globulin (SHBG), follicle-stimulating hormone, luteinizing hormone, inhibin B, and prolactin. Two oxidized urinary metabolites of DEHP were also measured in urine from 221 of the men. In multiple regression models adjusted for potential confounders, MEHP was inversely associated with testosterone, estradiol, and free androgen index (FAI). An interquartile range increase in MEHP was associated with 3.7% (95% confidence interval [CI], -6.8% to -0.5%) and 6.8% (95% CI, -11.2% to -2.4%) declines in testosterone and estradiol, respectively, relative to the population median hormone levels. There was limited evidence for effect modification of the inverse association between MEHP and FAI by the proportion of DEHP metabolites in the urine measured as MEHP (MEHP%), which is considered a phenotypic marker of less efficient metabolism of DEHP to its oxidized metabolites. Finally, the ratio of testosterone to estradiol was positively associated with MEHP (P = .07) and MEHP% (P = .007), suggesting potential relationships with aromatase suppression. In conclusion, these results suggest that urinary metabolites of DEHP are inversely associated with circulating steroid hormone levels in adult men. However, additional research is needed to confirm these findings.
Publication
Journal: Behavioral Neuroscience
March/14/2001
Abstract
The aim of this study was (a) to show that different measures of spatial cognition are modulated by the menstrual cycle and (b) to analyze which steroid is responsible for these cognitive alterations. The authors collected blood samples in 3-day intervals over 6 weeks from 12 young women with a regular menstrual cycle to analyze concentrations of estradiol, progesterone, testosterone, luteinizing hormone, and follicle-stimulating hormone. The performance on 3 spatial tests was measured during the menstrual and the midluteal phases. A significant cycle difference in spatial ability as tested by the Mental Rotation Test was found, with high scores during the menstrual phase and low scores during the midluteal phase. Testosterone had a strong and positive influence on mental rotation performance, whereas estradiol had a negative one. These results clearly indicate that testosterone and estradiol are able to modulate spatial cognition during the menstrual cycle.
Publication
Journal: Molecular Endocrinology
February/11/2007
Abstract
Classically, the FSH receptor (FSH-R) mediates its effects through coupling to guanine nucleotide-binding protein alpha S subunit (Galpha(s)) and activation of the cAMP/protein kinase A (PKA) signaling pathway. beta-Arrestins are rapidly recruited to the FSH-activated receptor and play key roles in its desensitization and internalization. Here, we show that the FSH-R expressed in HEK 293 cells activated ERK by two temporally distinct pathways dependent, respectively, on Galpha(s)/PKA and beta-arrestins. Galpha(s)/PKA-dependent ERK activation was rapid, transient, and blocked by H89 (a PKA inhibitor), but it was insensitive to small interfering RNA-mediated depletion of beta-arrestins. beta-Arrestin-dependent ERK activation was slower but more sustained and was insensitive to H89. We identified five Ser/Thr residues in the C terminus of the receptor (638-644) as a major phosphorylation site. Mutation of these residues into Ala (5A FSH-R) significantly reduced the stability of FSH-induced beta-arrestin 1 and 2 interaction when compared with the wild-type receptor. As expected, the 5A FSH-R-mediated cAMP accumulation was enhanced, and its internalization was reduced. In striking contrast, the ability of the 5A FSH-R to activate ERK via the beta-arrestin-dependent pathway was increased. G protein-coupled receptor kinase 5 (GRK5) and GRK6 were required for beta-arrestin-dependent ERK activation by both the wild-type and 5A FSH-R. By contrast, GRK2 depletion enhanced ERK activation by the wild-type FSH-R but not by the 5A FSH-R. In conclusion, we demonstrate the existence of a beta-arrestin-dependent, GRK-regulated mechanism for ERK activation by the FSH-R. A phosphorylation cluster in the C terminus of the FSH-R, identified as a site of beta-arrestin recruitment, positively regulated both desensitization and internalization but negatively regulated beta-arrestin-dependent ERK activation.
Publication
Journal: Journal of Biological Chemistry
August/29/1993
Abstract
Follistatin (FS), an activin-binding protein, is a monomer derived from two polypeptide core sequences of 315 (FS-315) and 288 (FS-288) amino acids originated from alternatively spliced mRNA. To define the structural heterogeneity of native FS, we purified six molecular forms of FS from porcine ovaries. Protein chemical analysis revealed that the structural differences among the six isoforms were caused by truncation of the carboxyl-terminal region and/or the presence of carbohydrate chains, resulting in the formation of FS-315, FS-288, and FS composed of 303 amino acids (FS-303) in various forms of glycosylation on the two potential Asn-linked glycosylation sites. The majority of FS isolated from porcine ovaries was FS-303, which may have been derived from FS-315 by proteolytic cleavage of the 12 COOH-terminal amino acids. All six molecular species have almost the same activin binding activity (Kd = 540-680 pM). By contrast, the COOH-terminal truncated form, FS-288, showed much higher affinity for the rat granulosa cell surface than FS-303, whereas FS-315 had no affinity. FS-288 bound to heparan sulfate-Sepharose CL-4B, but FS-315 did not, suggesting that the truncated forms of FS bind to heparan sulfate proteoglycans on the cell. COS cells transfected with the FS-288 DNA expressed the FS-288 protein, which adhered to the cell surface, but cells transfected with the FS-315 DNA secreted the expressed protein into the medium, which did not bind to the cell surface. In rat anterior pituitary culture, FS-288 (ED50 = 2 ng/ml) was more potent in suppressing follicle-stimulating hormone release than FS-303 (ED50 = 10 ng/ml) and FS-315 (ED50 = 20 ng/ml). These results suggest that cell-associated FS traps activin more tightly in the matrix, thereby more effectively blocking the activity of activin on heparan sulfate proteoglycans of the cell surface and that cell-associated FS plays an important role in controlling the various actions of activin in a paracrine or autocrine manner.
Publication
Journal: Arteriosclerosis, Thrombosis, and Vascular Biology
August/9/1995
Abstract
The goal of the study was to compare cardiovascular heart disease risk factors in women with polycystic ovary syndrome (PCOS) and matched control subjects. Women with PCOS have risk factors, including anovulation, hyperandrogenism, and insulin resistance, that suggest a male coronary heart disease risk-factor profile. A total of 206 women with PCOS were recruited by using records from a large reproductive endocrinology practice. A clinical diagnosis of PCOS was made if there was a history of chronic anovulation in association with either clinical evidence of androgen excess (hirsutism) or if total testosterone level was>> 2 nm/L or the luteinizing hormone/follicle-stimulating hormone ratio was greater than 2. The overall response rate for cases was 76%. A control population was obtained by using a combination of area voters' registration tapes and directories of households. A control subject was matched to each case subject by age +/- 5 years, race, and neighborhood. The response rate for recruitment of the first or second eligible control subject was 83.6%. The average age at initial interview was 35.9 +/- 7.4 years for case and 37.2 +/- 7.8 years for control subjects. Women with PCOS had significantly increased cardiovascular disease risk factors compared with control women. These included increases in body mass index, insulin, and triglyceride levels (P < .001), decreased total HDL and HDL2 levels (P < .01), and increased total cholesterol and fasting LDL levels, waist/hip ratio, and systolic blood pressure (P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)
Publication
Journal: BJOG: An International Journal of Obstetrics and Gynaecology
December/25/2002
Abstract
OBJECTIVE
To evaluate the mid-term efficacy and complications of uterine artery embolisation in women with symptomatic fibroids. To assess reduction in uterine and dominant fibroid volumes using ultrasound and magnetic resonance imaging.
METHODS
Prospective observational single-centre study.
METHODS
A district general hospital in Surrey and a private hospital in London.
METHODS
Four hundred consecutive women were treated between December 1996 and February 2001. Indications for treatment were menorrhagia, menstrual pain, abdominal swelling or bloating and other pressure effects. Uterine artery embolisation was performed using polyvinyl alcohol particles and platinum coils.
METHODS
Imaging was performed before embolisation and at regular intervals thereafter. Clinical evaluation was made at regular intervals after embolisation to assess patient outcome.
RESULTS
Bilateral uterine artery embolisation was achieved in 395 women, while 5 women had a unilateral procedure. With a mean clinical follow up of 16.7 months, menstrual bleeding was improved in 84% of women and menstrual pain was improved in 79%. Using ultrasound, the median uterine and dominant fibroid volumes before embolisation were 608 and 112 cc, respectively, and after embolisation 255 and 19 cc, respectively (P = .0001). Three (1%) infective complications requiring emergency hysterectomy occurred. Twenty-three (6%) patients had clinical failure or recurrence. Of these, nine (2%) had a hysterectomy. Twenty-six (7%) women had permanent amenorrhoea after embolisation including four patients under the age of 45 (2%). Of these, amenorrhea started between 4 and 18 months after embolisation, and only three had elevated follicle stimulating hormone levels when amenorrhea developed. Thirteen (4%) women had chronic vaginal discharge considered as a major irritant. Thirteen pregnancies occurred in 12 patients. Ninety-seven percent of women were pleased with the outcome and would recommend this treatment to others.
CONCLUSIONS
Uterine artery embolisation is associated with a high clinical success rate and good fibroid volume reduction. Infective complications requiring hysterectomy, amenorrhoea under the age of 45 and chronic vaginal discharge may complicate the procedure.
Publication
Journal: Reproductive Health
February/22/2012
Abstract
BACKGROUND
A high body mass index (BMI) has been associated with reduced semen quality and male subfecundity, but no studies following obese men losing weight have yet been published. We examined semen quality and reproductive hormones among morbidly obese men and studied if weight loss improved the reproductive indicators.
METHODS
In this pilot cohort study, 43 men with BMI>> 33 kg/m² were followed through a 14 week residential weight loss program. The participants provided semen samples and had blood samples drawn, filled in questionnaires, and had clinical examinations before and after the intervention. Conventional semen characteristics as well as sperm DNA integrity, analysed by the sperm chromatin structure assay (SCSA) were obtained. Serum levels of testosterone, estradiol, sex hormone-binding globulin (SHBG), luteinizing hormone (LH), follicle-stimulating hormone (FSH), anti-Müllerian hormone (AMH) and inhibin B (Inh-B) were measured.
RESULTS
Participants were from 20 to 59 years of age (median = 32) with BMI ranging from 33 to 61 kg/m². At baseline, after adjustment for potential confounders, BMI was inversely associated with sperm concentration (p = 0.02), total sperm count (p = 0.02), sperm morphology (p = 0.04), and motile sperm (p = 0.005) as well as testosterone (p = 0.04) and Inh-B (p = 0.04) and positively associated to estradiol (p < 0.005). The median (range) percentage weight loss after the intervention was 15% (3.5-25.4). Weight loss was associated with an increase in total sperm count (p = 0.02), semen volume (p = 0.04), testosterone (p = 0.02), SHBG (p = 0.03) and AMH (p = 0.02). The group with the largest weight loss had a statistically significant increase in total sperm count [193 millions (95% CI: 45; 341)] and normal sperm morphology [4% (95% CI: 1; 7)].
CONCLUSIONS
This study found obesity to be associated with poor semen quality and altered reproductive hormonal profile. Weight loss may potentially lead to improvement in semen quality. Whether the improvement is a result of the reduction in body weight per se or improved lifestyles remains unknown.
Publication
Journal: Nature Medicine
December/18/2006
Abstract
Throughout spermatogenesis, developing germ cells remain attached to Sertoli cells via testis-specific anchoring junctions. If adhesion between these cell types is compromised, germ cells detach from the seminiferous epithelium and infertility often results. Previously, we reported that Adjudin is capable of inducing germ cell loss from the epithelium. In a small subset of animals, however, oral administration of Adjudin (50 mg per kg body weight (b.w.) for 29 d) resulted in adverse effects such as liver inflammation and muscle atrophy. Here, we report a novel approach in which Adjudin is specifically targeted to the testis by conjugating Adjudin to a recombinant follicle-stimulating hormone (FSH) mutant, which serves as its 'carrier'. Using this approach, infertility was induced in adult rats when 0.5 microg Adjudin per kg b.w. was administered intraperitoneally, which was similar to results when 50 mg per kg b.w. was given orally. This represents a substantial increase in Adjudin's selectivity and efficacy as a male contraceptive.
Publication
Journal: Science of the Total Environment
June/3/2009
Abstract
Despite documented widespread human exposure to polybrominated diphenyl ethers (PBDEs) through dietary intake and contact with or inhalation of indoor dust, along with growing laboratory evidence for altered endocrine function following exposure, human studies of PBDE exposure and endocrine effects remain limited. We conducted a preliminary study within an ongoing study on the impact of environmental exposures on male reproductive health. We measured serum hormone levels and PBDE concentrations (BDE 47, 99 and 100) in house dust from 24 men recruited through a US infertility clinic. BDE 47 and 99 were detected in 100% of dust samples, and BDE 100 was detected in 67% of dust samples, at concentrations similar to those reported in previous US studies. In multivariable regression models adjusted for age and BMI, there was a statistically significant inverse relationship between dust PBDE concentrations and free androgen index. Dust PBDE concentrations were also strongly and inversely associated with luteinizing hormone (LH) and follicle stimulating hormone (FSH), and positively associated with inhibin B and sex hormone binding globulin (SHBG). Finally, consistent with limited recent human studies of adults, PBDEs were positively associated with free T4. In conclusion, the present study provides compelling evidence of altered hormone levels in relation to PBDE exposures estimated as concentrations in house dust, and that house dust is an important source of human PBDE exposure, but more research is urgently needed.
Publication
Journal: Archives of general psychiatry
February/1/2001
Abstract
BACKGROUND
Stress and corticotropin-releasing hormone inhibit the reproductive axis. We hypothesized that reproductive axis hormone secretion, particularly luteinizing hormone secretion, is inhibited in women with depression, similar to what has been observed to be caused by stress in numerous species.
METHODS
Blood samples were collected every 10 minutes for 12 hours in 25 untreated premenopausal women with depression and 25 nondepressed women who were matched by age and menstrual cycle day. Samples were assayed for luteinizing hormone, follicle-stimulating hormone, estradiol, and progesterone.
RESULTS
The mean plasma estradiol level was 30% lower in the follicular phase in women with depression than in their matched controls: 191 + 136 vs 261 + 169 pmol/L (52 + 37 vs 71 + 46 pg/mL). The half-life of luteinizing hormone was significantly shorter in women with depression than in their matched controls during both the follicular (22% shorter) and luteal (15% shorter) phases.
CONCLUSIONS
The blood levels of reproductive hormones were mostly normal in women with depression, but the blood level of estradiol was significantly lower. Estradiol is known to affect a number of neurotransmitter systems in the brain. Arch Gen Psychiatry. 2000;57:1157-1162.
Publication
Journal: Journal of molecular and applied genetics
October/20/1982
Abstract
The gene encoding the common alpha subunit of the four human glycoprotein hormones, chorionic gonadotropin (CG), luteinizing hormone (LH), follicle stimulating hormone (FSH), and thyroid stimulating hormone (TSH), has been cloned in a bacteriophage lambda vector. Restriction endonuclease digestion of total human DNA suggests that the common alpha subunit is coded for by a single gene. Three distinct polymorphic hybridization patterns have been observed for this gene in the human population. The cloned gene encompasses a total of 9.4 kilobases (kb) and contains three intervening sequences whose locations have been established by restriction enzyme mapping and by DNA sequencing. One of the intervening sequences is located in the 5' untranslated region, generating a leader sequence that is separated from the rest of the gene by 6.4 kb. The other two intervening sequences are 1.7 and 0.4 kb long and are located within codon number 6, and between codons 67 and 68, respectively. The location of the 5' end of the mature transcript has been established by priming placental mRNA with a restriction fragment obtained from the cloned cDNA. A transcript of similar size for the alpha subunit gene has been detected in both the pituitary, where the gene is expressed for the synthesis of LH, FSH, and TSH, and the placenta, where the gene is expressed for the synthesis of CG. When parts of the 5' untranslated nucleotide sequences of the alpha subunit and the human growth hormone genes are compared a highly homologous region is observed. These otherwise unrelated genes share the common feature that they encode a secreted pituitary polypeptide hormone.
Publication
Journal: Endocrinology
September/15/2003
Abstract
Although FSH receptors are linked to the cAMP second messenger system, additional intracellular signaling pathways appear to be required for the induction of aromatase and the LH receptor during granulosa cell differentiation. We employed adenovirus vectors to modulate specific intracellular signaling systems in undifferentiated granulosa cells to identify the signaling pathway(s) that may be involved in the FSH-mediated induction of aromatase and the LH receptor. Expression of either the constitutively activated human LH receptor D578H or the constitutively active human G(s)alpha Q227L resulted in increased cAMP production without increasing aromatase activity or mRNA levels for the LH receptor. To explore the contributions of other pathways, we expressed the constitutively activated forms MAPK kinase (MEK) and protein kinase B (PKB). Neither MEK nor PKB alone increased estrogen or progesterone production by undifferentiated granulosa cells. Stimulation of granulosa cells by FSH in the presence of the constitutively active PKB, but not MEK, led to an amplification of FSH-induced aromatase and LH receptor mRNA levels, whereas a dominant negative PKB vector completely abolished the actions of FSH. The expression of the constitutively active PKB in combination with the constitutively active LH receptor D578H, the constitutively active G(s)alpha Q227L, or 8-bromo-cAMP led to an induction of aromatase as well as LH receptor mRNA comparable to that seen in cells stimulated with FSH alone. These results demonstrate that PKB is an essential component of the FSH-mediated granulosa cell differentiation and that both PKB and G(s)alpha signaling pathways are required.
Publication
Journal: New England Journal of Medicine
March/21/2006
Abstract
BACKGROUND
Single-embryo transfer has been recommended to reduce the incidence of multiple gestations when in vitro fertilization is performed in women under 36 years of age. We designed a prospective, randomized, controlled trial to determine whether there were any differences in the rates of pregnancy and delivery between women undergoing transfer of a single cleavage-stage (day 3) embryo and those undergoing transfer of a single blastocyst-stage (day 5) embryo.
METHODS
We studied 351 infertile women under 36 years of age who were randomly assigned to undergo transfer of either a single cleavage-stage embryo (176 patients) or a single blastocyst-stage embryo (175 patients). Multifollicular ovarian stimulation was performed with a gonadotropin-releasing hormone antagonist and recombinant follicle-stimulating hormone.
RESULTS
The study was terminated early after a prespecified interim analysis (which included 50 percent of the planned number of patients) found a higher rate of pregnancy among women undergoing transfer of a single blastocyst-stage embryo (P=0.02). The rate of delivery was also significantly higher in this group than in the group undergoing transfer of a single cleavage-stage embryo (32.0 percent vs. 21.6 percent; relative risk, 1.48; 95 percent confidence interval, 1.04 to 2.11). Two multiple births occurred, both of monozygotic twins, both of which were in the group undergoing transfer of a single cleavage-stage embryo.
CONCLUSIONS
These findings support the transfer of a single blastocyst-stage (day 5) embryo in infertile women under 36 years of age.
Publication
Journal: Orphanet Journal of Rare Diseases
October/1/2007
Abstract
The term Klinefelter syndrome (KS) describes a group of chromosomal disorder in which there is at least one extra X chromosome to a normal male karyotype, 46,XY. XXY aneuploidy is the most common disorder of sex chromosomes in humans, with prevalence of one in 500 males. Other sex chromosomal aneuploidies have also been described, although they are much less frequent, with 48,XXYY and 48,XXXY being present in 1 per 17,000 to 1 per 50,000 male births. The incidence of 49,XXXXY is 1 per 85,000 to 100,000 male births. In addition, 46,XX males also exist and it is caused by translocation of Y material including sex determining region (SRY) to the X chromosome during paternal meiosis. Formal cytogenetic analysis is necessary to make a definite diagnosis, and more obvious differences in physical features tend to be associated with increasing numbers of sex chromosomes. If the diagnosis is not made prenatally, 47,XXY males may present with a variety of subtle clinical signs that are age-related. In infancy, males with 47,XXY may have chromosomal evaluations done for hypospadias, small phallus or cryptorchidism, developmental delay. The school-aged child may present with language delay, learning disabilities, or behavioral problems. The older child or adolescent may be discovered during an endocrine evaluation for delayed or incomplete pubertal development with eunuchoid body habitus, gynecomastia, and small testes. Adults are often evaluated for infertility or breast malignancy. Androgen replacement therapy should begin at puberty, around age 12 years, in increasing dosage sufficient to maintain age appropriate serum concentrations of testosterone, estradiol, follicle stimulating hormone (FSH), and luteinizing hormone (LH). The effects on physical and cognitive development increase with the number of extra Xs, and each extra X is associated with an intelligence quotient (IQ) decrease of approximately 15-16 points, with language most affected, particularly expressive language skills.
Publication
Journal: Environmental Health Perspectives
December/14/2010
Abstract
BACKGROUND
Rodent and in vitro studies have demonstrated the estrogenicity of bisphenol A (BPA). However, few studies have examined the relationship between human exposure to BPA and male reproductive function.
OBJECTIVE
We investigated the relationships between environmental BPA exposure and reproductive parameters, including semen quality and male reproductive hormones, in prospectively recruited fertile men.
METHODS
Participants (n = 375) were partners of pregnant women who participated in the Study for Future Families in four U.S. cities, and all of the men provided blood, semen, and urine samples. BPA was measured in urine. Serum samples were analyzed for reproductive hormones, including follicle-stimulating hormone, luteinizing hormone (LH), testosterone, inhibin B, estradiol, and sex hormone-binding globulin (SHBG), as well as the free androgen index (FAI). Semen analyses were performed according to World Health Organization criteria. Pearson correlations were used for unadjusted analyses, and multiple linear regression analyses were used to examine associations controlling for age, body mass index, smoking, ethnicity, urinary creatinine concentration, time of sample collection, and duration of abstinence.
RESULTS
After multivariate adjustment, we observed no significant associations between any semen parameter and urinary BPA concentration. However, a significant inverse association was found between urinary BPA concentration and FAI levels and the FAI/LH ratio, as well as a significant positive association between BPA and SHBG.
CONCLUSIONS
Our results suggest that, in fertile men, exposure to low environmental levels of BPA may be associated with a modest reduction in markers of free testosterone, but any effects on reproductive function are likely to be small, and of uncertain clinical significance.
Publication
Journal: Nature
November/20/1984
Abstract
Human reproduction is controlled by the hypothalamic-pituitary-gonadal axis laid down early in fetal development. Luteinizing hormone releasing hormone (LHRH), also termed gonadotropin releasing hormone (GnRH), is a decapeptide and is a key molecule in this control circuit. It is produced by hypothalamic neurones, secreted in a pulsatile manner into the capillary plexus of the median eminence and effects the release of luteinizing hormone and follicle stimulating hormone from gonadotropic cells in the anterior pituitary. The peptide may have further functions, including behavioural ones, as LHRH or LHRH-like immunoreactivity has been found in gonadal tissue, placenta and the central nervous system, and exogenously administered LHRH is shown to affect behaviour. To investigate the biosynthesis of LHRH, we have now isolated cloned genomic and cDNA sequences encoding the precursor form of LHRH, the existence of which had been suggested from chromatographic studies of hypothalamic and placental extracts. These DNA sequences code for a protein of 92 amino acids in which the LHRH decapeptide is preceded by a signal peptide of 23 amino acids and followed by a Gly-Lys-Arg sequence, as expected for enzymatic cleavage of the decapeptide from its precursor and amidation of the carboxy-terminal of LHRH.
Publication
Journal: International Journal of Radiation Oncology Biology Physics
December/16/2010
Abstract
OBJECTIVE
To identify single nucleotide polymorphisms (SNPs) associated with erectile dysfunction (ED) among African-American prostate cancer patients treated with external beam radiation therapy.
METHODS
A cohort of African-American prostate cancer patients treated with external beam radiation therapy was observed for the development of ED by use of the five-item Sexual Health Inventory for Men (SHIM) questionnaire. Final analysis included 27 cases (post-treatment SHIM score ≤7) and 52 control subjects (post-treatment SHIM score ≥16). A genome-wide association study was performed using approximately 909,000 SNPs genotyped on Affymetrix 6.0 arrays (Affymetrix, Santa Clara, CA).
RESULTS
We identified SNP rs2268363, located in the follicle-stimulating hormone receptor (FSHR) gene, as significantly associated with ED after correcting for multiple comparisons (unadjusted p = 5.46 × 10(-8), Bonferroni p = 0.028). We identified four additional SNPs that tended toward a significant association with an unadjusted p value < 10(-6). Inference of population substructure showed that cases had a higher proportion of African ancestry than control subjects (77% vs. 60%, p = 0.005). A multivariate logistic regression model that incorporated estimated ancestry and four of the top-ranked SNPs was a more accurate classifier of ED than a model that included only clinical variables.
CONCLUSIONS
To our knowledge, this is the first genome-wide association study to identify SNPs associated with adverse effects resulting from radiotherapy. It is important to note that the SNP that proved to be significantly associated with ED is located within a gene whose encoded product plays a role in male gonad development and function. Another key finding of this project is that the four SNPs most strongly associated with ED were specific to persons of African ancestry and would therefore not have been identified had a cohort of European ancestry been screened. This study demonstrates the feasibility of a genome-wide approach to investigate genetic predisposition to radiation injury.
Publication
Journal: American Journal of Psychiatry
January/27/2005
Abstract
OBJECTIVE
Mood and reproductive function were prospectively evaluated in asymptomatic premenopausal women to determine whether the onset of depression was temporally linked to the perimenopause.
METHODS
Twenty-nine asymptomatic, regularly cycling women were monitored longitudinally for an average of 5 years until at least 6 months of amenorrhea occurred. Outcome measures included mood ratings and menstrual diaries completed daily, the Structured Clinical Interview for DSM-IV, and plasma levels of follicle-stimulating hormone obtained at 3-6-month intervals. The number of episodes of depression and their timing relative to the final menstrual period were determined. Differences in outcome measures between women who did and did not become depressed during the perimenopause were determined by Student's t test, chi-square tests, and Fisher's exact test.
RESULTS
The authors observed 11 episodes of new-onset depression in nine of the 29 women. In the 24 months surrounding the last menstrual period nine episodes of depression were observed. Six of the nine women who became depressed during the study had no prior depressive episodes. For the 24 months surrounding the final menses, the risk for onset of depression was 14 times as high as for a 31-year premenopausal period of time. Women who developed depression during the perimenopause were not distinguished from those who remained asymptomatic on the basis of symptom profile, duration of the perimenopause, endocrine measures, or past historical variables.
CONCLUSIONS
These preliminary data suggest that events related to the late perimenopause may be associated with an increased susceptibility to develop depression in some women.
Publication
Journal: JAMA - Journal of the American Medical Association
December/26/2004
Abstract
BACKGROUND
The onset of human menopause is thought to be caused solely by ovarian failure and oocyte depletion. However, clinical symptoms and certain recent data in perimenopausal women suggest central nervous system involvement.
OBJECTIVE
To determine if modifications of hypothalamic-pituitary response to estrogen feedback mechanisms occur in older reproductive-age women as a mechanism of the onset of menopause.
METHODS
The Study of Women's Health Across the Nation (SWAN) is a multiethnic observational cohort study of the menopausal transition in 3302 women at 7 US sites. Of the subcohort of 840 women who participated in the Daily Hormone Study between 1997 and 1999, 680 women had evidence of luteal activity. The remaining 160 women (19%) did not have luteal activity and are the subject of this report.
METHODS
Daily urinary hormone levels of estrogen and progesterone metabolites, luteinizing hormone (LH), and follicle-stimulating hormone (FSH).
RESULTS
Three groups of women were studied: those with estrogen increases with an LH surge, those with estrogen increases without an LH surge, and those with neither. There were no differences in age or ethnicity among the 3 groups of women. Women in the third group (no increases) experienced more menopausal symptoms (hot flashes) than did women in the other groups with estrogen increases. In older reproductive-age women, the frequent existence of anovulatory cycles with estrogen peaks, equivalent to those that result in LH surges in younger women, yet in which no LH surges occur, indicates failure of estrogen-positive feedback on LH secretion. In other anovulatory cycles, follicular-phase estrogen levels did not lower LH secretion as occurs in cycles of younger women, indicating decreased estrogen-negative feedback on LH secretion.
CONCLUSIONS
Our findings are compatible with hypothalamic-pituitary insensitivity to estrogen in aging perimenopausal women.
Publication
Journal: Journal of Biological Chemistry
February/9/2003
Abstract
Bone morphogenetic protein-15 (BMP-15), an oocyte growth factor belonging to the transforming growth factor-beta superfamily, has recently been shown to be necessary for normal female fertility in mammals. We have previously demonstrated that BMP-15 regulates granulosa cell (GC) proliferation and differentiation; namely, BMP-15 promotes GC mitosis, suppresses follicle-stimulating hormone (FSH) receptor expression, and stimulates kit ligand expression. Although the role of BMP-15 in female reproduction has progressively deserved much attention, there is nothing known to date about the signaling pathway and receptors for BMP-15. Using rat primary GCs and a human GC cell line, COV434, we have now found that administration of BMP-15 causes a rapid and transient phosphorylation, thus activation, of the Smad1/5/8 pathway. BMP-15 also stimulated promoter activity of a selective BMP-responsive reporter construct, further demonstrating the stimulation of Smad1/5/8 signaling by BMP-15. In contrast, BMP-15 stimulation of Smad2 phosphorylation was very weak. To identify the receptors for BMP-15, we utilized recombinant extracellular domains of individual transforming growth factor-beta superfamily receptors and found that activin receptor-like kinase-6 extracellular domain most effectively co-immunoprecipitates with BMP-15, whereas BMP receptor type II extracellular domain was most effective in inhibiting BMP-15 bioactivity on FSH-induced progesterone production and GC thymidine incorporation. We also investigated whether activation of the MAPK pathway is necessary for BMP-15 biological activity and found that the addition of U0126, an inhibitor of ERK1/2 phosphorylation, suppresses BMP-15 activity on GC mitotsis but not on FSH-induced progesterone production, suggesting a selective signaling cascade in GC proliferation and differentiation.
Publication
Journal: Archives of general psychiatry
January/22/2003
Abstract
BACKGROUND
Few studies have determined the impact of a lifetime history of major depression on an early transition to menopause.
METHODS
Reproductive and psychiatric interviews and early follicular-phase blood specimens were obtained at study enrollment and every 6 months during 36 months of follow-up from 332 women with and 644 women without a history of major depression, 36 to 45 years of age. We used menstrual cycle markers to determine inception of perimenopause, defined as time from study enrollment to a follow-up interview with: (1) 7-day or more change in menstrual cycle length; (2) a change in menstrual flow amount or duration; or (3) amenorrhea lasting at least 3 months.
RESULTS
Women with a history of depression had 1.2 times the rate of perimenopause of women with no such history (95% confidence interval, 0.9-1.6). Compared with nondepressed women, depressed women with more pronounced depressive symptoms at study enrollment (Hamilton Rating Scale for Depression scores >8) had twice the risk of an earlier perimenopausal transition. Among the women with greater depressive symptoms (Hamilton scores >8), those who also reported use of antidepressants had nearly 3 times the risk of an earlier perimenopausal transition (hazard ratio, 2.7; 95% confidence interval, 1.5-4.8) of nondepressed women. Women with a lifetime history of depression also had higher follicle-stimulating hormone and luteinizing hormone levels and lower estradiol levels at study enrollment and during the follow-up period after adjustment for covariates.
CONCLUSIONS
A lifetime history of major depression may be associated with an early decline in ovarian function.
Publication
Journal: Journal of Clinical Oncology
December/16/1996
Abstract
OBJECTIVE
The current study evaluates the extent and reversibility of late sequelae after chemotherapy in longterm survivors of testicular cancer. The influence of therapy and patient characteristics and the relationship between different toxicities are assessed.
METHODS
Ninety patients with a median age of 28 years (range, 19 to 53) and a median followup time of 58 months (range, 15 to 159) participated in the clinical examinations, a personal interview, and technical investigations. Overall health and the impact of late toxicity were assessed by the patients. All patients were in complete remission (CR) for at least 1 year. Chemotherapy had consisted of cisplatin (P), bleomycin (B), and vinblastine (V) in 30 patients (33%); P, B, and etoposide (E) in 26 patients (29%); P, B, E, and a vinca alkaloid in 22 patients (24%); and other P-based combination regimens in 12 patients (13%).
RESULTS
Alterations of gonadotropin levels (follicle-stimulating hormone [FSH] luteinizing hormone [LH]) in up to 68% of patients and Leydig cell insufficiency in one third of patients were the most frequently detected abnormalities. Approximately 20% of patients had low serum magnesium [Mg] or phosphate levels, or elevated creatinine levels. Cardiovascular risk factors were identified in one third of patients with elevated serum cholesterol levels with or without obesity; 15% had developed arterial hypertension after chemotherapy. The most frequent symptomatic toxicities were Raynaud's phenomenon (RP) in 30% of patients, ototoxicity in 21%, and peripheral neuropathy in 17%. Major risk factors for the development of toxicity were cumulative dose of P (P < .0001 for ototoxicity and neurotoxicity; P < .01 for overall toxicity, gonadal toxicity, and dehydroepiandrosteron elevation; P < .05 for hypertension and Mg depletion) and type of chemotherapy (57% of PVB-treated patients v25% of PEB +/- vincristine-treated patients with RP; P < .01).
CONCLUSIONS
The cumulative dose of P was a major predictor for toxicity. Patients and treatment characteristics such as noise exposure, age, history of smoking, and mode of B application were less important. Further clinical trials should evaluate the sequelae of chemotherapy treatment for testicular cancer prospectively.
Publication
Journal: Molecular Endocrinology
August/2/1999
Abstract
The role of FSH in gonadal tumorigenesis and, in particular, in human ovarian cancer has been debated. It is also unclear what role the elevated FSH levels in the inhibin-deficient mouse play in the gonadal tumorigenesis. To directly assess the role of FSH in gonadal growth, differentiation, and gonadal tumorigenesis, we have generated both gain-of-function and loss-of-function transgenic mutant mice. In the gain-of-function model, we have generated transgenic mice that ectopically overexpress human FSH from multiple tissues using a mouse metallothionein-1 promoter, achieving levels far exceeding those seen in postmenopausal women. Male transgenic mice are infertile despite normal testicular development and demonstrate enlarged seminal vesicles secondary to elevated serum testosterone levels. Female transgenic mice develop highly hemorrhagic and cystic ovaries, have elevated serum estradiol and progesterone levels, and are infertile, mimicking the features of human ovarian hyperstimulation and polycystic ovarian syndromes. Furthermore, the female transgenic mice develop enlarged and cystic kidneys and die between 6-13 weeks as a result of urinary bladder obstruction. In a complementary loss-of-function approach, we have generated double-homozygous mutant mice that lack both inhibin and FSH by a genetic intercross. In contrast to male mice lacking inhibin alone, 95% of which die of a cancer cachexia-like syndrome by 12 weeks of age, only 30% of the double-mutant male mice lacking both FSH and inhibin die by 1 yr of age. The remaining double-mutant male mice develop slow-growing and less hemorrhagic testicular tumors, which are noted after 12 weeks of age, and have minimal cachexia. Similarly, the double-mutant female mice develop slow-growing, less hemorrhagic ovarian tumors, and 70% of these mice live beyond 17 weeks. The double-mutant mice demonstrate minimal cachexia in contrast to female mice lacking only inhibin, which develop highly hemorrhagic ovarian tumors, leading to cachexia and death by 17 weeks of age in 95% of the cases. The milder cachexia-like symptoms of the inhibin and FSH double-mutant mice are correlated with low levels of serum estradiol and activin A and reduced levels of aromatase mRNA in the gonadal tumors. Based on these and our previous genetic analyses, we conclude that elevated FSH levels do not directly cause gonadal tumors. However, these results suggest FSH is an important trophic modifier factor for gonadal tumorigenesis in inhibin-deficient mice.
Publication
Journal: Animal Reproduction Science
October/22/2003
Abstract
Members of the transforming growth factor-beta (TGF-beta) superfamily have wide-ranging influences on many tissue and organ systems including the ovary. Two recently discovered TGF-beta superfamily members, growth/differentiation factor-9 (GDF-9) and bone morphogenetic protein-15 (BMP-15; also designated as GDF-9B) are expressed in an oocyte-specific manner from a very early stage and play a key role in promoting follicle growth beyond the primary stage. Follicle growth to the small antral stage does not require gonadotrophins but appears to be driven by local autocrine/paracrine signals from both somatic cell types (granulosa and theca) and from the oocyte. TGF-beta superfamily members expressed by follicular cells and implicated in this phase of follicle development include TGF-beta, activin, GDF-9/9B and several BMPs. Acquisition of follicle-stimulating hormone (FSH) responsiveness is a pre-requisite for growth beyond the small antral stage and evidence indicates an autocrine role for granulosa-derived activin in promoting granulosa cell proliferation, FSH receptor expression and aromatase activity. Indeed, some of the effects of FSH on granulosa cells may be mediated by endogenous activin. At the same time, activin may act on theca cells to attenuate luteinizing hormone (LH)-dependent androgen production in small to medium-size antral follicles. Dominant follicle selection appears to depend on differential FSH sensitivity amongst a growing cohort of small antral follicles. Activin may contribute to this selection process by sensitizing those follicles with the highest "activin tone" to FSH. Production of inhibin, like oestradiol, increases in selected dominant follicles, in an FSH- and insulin-like growth factor-dependent manner and may exert a paracrine action on theca cells to upregulate LH-induced secretion of androgen, an essential requirement for further oestradiol secretion by the pre-ovulatory follicle. Like activin, BMP-4 and -7 (mostly from theca), and BMP-6 (mostly from oocyte), can enhance oestradiol and inhibin secretion by bovine granulosa cells while suppressing progesterone secretion; this suggests a functional role in delaying follicle luteinization and/or atresia. Follistatin, on the other hand, may favor luteinization and/or atresia by bio-neutralizing intrafollicular activin and BMPs. Activin receptors are expressed by the oocyte and activin may have a further intrafollicular role in the terminal stages of follicle differentiation to promote oocyte maturation and developmental competence. In a reciprocal manner, oocyte-derived GDF-9/9B may act on the surrounding cumulus granulosa cells to attenuate oestradiol output and promote progesterone and hyaluronic acid production, mucification and cumulus expansion.
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