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1.
Maturitas ; 147: 26-33, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33832644

RESUMO

OBJECTIVE: The menopausal transition is characterized by progressive changes in ovarian function and increasing circulating levels of gonadotropins, with some women having irregular menstrual cycles well before their final menstrual period. These observations indicate a progressive breakdown of the hypothalamic-pituitary-ovarian axis often associated with an increase in menopausal symptoms. Relationships between vasomotor symptoms (VMS) and depressed mood and sleep as well as a bidirectional association between VMS and depressed mood in mid-life women have been reported, but the endocrine foundations and hormone profiles associated with these symptoms have not been well described. Our objective was to determine the relationship between daily urinary hormone profiles and daily logs of affect and VMS during the early perimenopausal transition. STUDY DESIGN: SWAN, the Study of Women's Health Across the Nation, is a large, mutli-ethnic, multisite cohort study of 3302 women aged 42-52 at baseline, designed to examine predictors of health and disease in women as they traversed the menopause. Inclusion criteria were: an intact uterus and at least one ovary present, at least one menstrual period in the previous three months, no use of sex steroid hormones in the previous three months, and not pregnant or lactating. A subset (n = 849) of women aged 43-53 years from all study sites in the first Daily Hormone Study collection were evaluated for this substudy. OUTCOME MEASURES: We measured daily VMS, and urinary hormones: follicle stimulating hormone (FSH), luteinizing hormone (LH), pregnanediol glucuronide (PdG) and estradiol (estrone conjugate, E1C). RESULTS: A variable pattern of LH and negative LH feedback were the hormone patterns most strongly associated with increased VMS. In contrast, no hormone pattern was significantly related to negative mood. CONCLUSION: Fluctuations of LH associated with low progesterone production were associated with VMS but not negative mood, suggesting different endocrine patterns may be related to increased negative mood than to the occurrence of VMS.


Assuntos
Hormônio Luteinizante/urina , Perimenopausa/urina , Pregnanodiol/análogos & derivados , Progesterona/metabolismo , Adulto , Afeto , Estradiol/urina , Feminino , Hormônio Foliculoestimulante/urina , Humanos , Pessoa de Meia-Idade , Pregnanodiol/urina , Estados Unidos , Sistema Vasomotor , Saúde da Mulher
2.
Brain Res ; 1721: 146303, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31279842

RESUMO

Dehydroepiandrosterone-sulfate (DHEAS) is an adrenal androgen that is, in part, aromatized to estradiol. It continues to be produced after menopause and provides estrogenicity after depletion of ovarian hormones. Estradiol depletion contributes to memory circuitry changes over menopause, including changes in hippocampal (HIPP) and dorsolateral- and ventrolateral-prefrontal cortex (DLPFC; VLPFC) function. Further, major depressive disorder (MDD) patients have, in general, lower levels of estradiol and lower DHEAS than healthy controls, thus potentially a higher risk of adverse menopausal outcomes. We investigated whether higher DHEAS levels after menopause is associated with better memory circuitry function, especially in women with MDD. 212 adults (ages 45-55, 50% women) underwent clinical and fMRI testing. Participants performed a working memory (WM) N-back task and an episodic memory verbal encoding (VE) task during fMRI scanning. DHEAS levels were significantly associated with memory circuitry function, specifically in MDD postmenopausal women. On the WM task, lower DHEAS levels were associated with increased HIPP activity. On the VE task, lower DHEAS levels were associated with decreased activity in the HIPP and VLPFC. In contrast, there was no association between DHEAS levels and memory circuitry function in MDD pre/perimenopausal women, men, and non-MDD participants regardless of sex and reproductive status. In fact, MDD postmenopausal women with higher levels of DHEAS were similar to MDD pre/perimenopausal women and men. Thus, memory circuitry deficits associated with MDD and a lower ability of the adrenal gland to produce DHEAS after menopause may contribute to a lower ability to maintain intact memory function with age.


Assuntos
Envelhecimento/fisiologia , Sulfato de Desidroepiandrosterona/metabolismo , Memória/fisiologia , Glândulas Suprarrenais/metabolismo , Androgênios/fisiologia , Encéfalo/metabolismo , Transtorno Depressivo Maior/fisiopatologia , Estradiol/metabolismo , Feminino , Hipocampo/metabolismo , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Memória de Curto Prazo , Menopausa , Pessoa de Meia-Idade , Córtex Pré-Frontal/metabolismo , Caracteres Sexuais , Fatores Sexuais
3.
J Clin Endocrinol Metab ; 102(7): 2218-2229, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28368525

RESUMO

Context: Menstrual cycle hormone patterns in women approaching menopause are inadequately studied. Objective: To describe day-to-day menstrual cycle hormones in women as they approach menopause from the Study of Women's Health Across the Nation Daily Hormone Study (DHS). Design: DHS enrollees collected daily urine for one entire menstrual cycle or up to 50 days, whichever came first, annually, up to the final menstrual period (FMP) or for up to 10 years. Setting: Seven sites across the United States. Participants: A total of 511 premenopausal or early perimenopausal women at enrollment, within 10 years before menopause. Intervention: Time-to-FMP measurement. Main Outcome Measures: Evidence of luteal activity (ELA), determined using objective algorithms. Menstrual cycle/segment length; whole cycle, and segment integrated urinary luteinizing hormone, follicle-stimulating hormone, estrone conjugates, and pregnanediol glucuronide (Pdg) for each year, organized around the FMP. Results: Mean menstrual cycle length was remarkably preserved at 26 to 27 days in ELA cycles; non-ELA cycles had greater variability. The percentage of cycles that were ELA remained high until 5 years before the FMP (87.9%); only 22.8% of cycles within 1 year of the FMP were ELA. Whole cycle hormones remained relatively stable up to 3 years before the FMP, when gonadotropins began to increase. Pdg excretion declined slowly with progress to the FMP, but Pdg patterns of ELA cycles remained distinguishable from non-ELA. Conclusions: Menstrual cycle hormone patterns in perimenopausal women resemble those of midreproductive-aged women until 5 years before menopause, and presumably ovulatory cycles retain a potentially fertile pattern up to the end of reproductive life.


Assuntos
Hormônios/metabolismo , Ciclo Menstrual/metabolismo , Perimenopausa/metabolismo , Negro ou Afro-Americano , Povo Asiático , Índice de Massa Corporal , Corpo Lúteo/fisiologia , Estradiol/metabolismo , Estrona/metabolismo , Feminino , Hormônio Foliculoestimulante/metabolismo , Humanos , Hormônio Luteinizante/metabolismo , Ciclo Menstrual/etnologia , Pessoa de Meia-Idade , Perimenopausa/etnologia , Pregnanodiol/análogos & derivados , Pregnanodiol/metabolismo , Pré-Menopausa/etnologia , Pré-Menopausa/metabolismo , População Branca , Saúde da Mulher
4.
Anat Rec (Hoboken) ; 299(7): 973-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27084043

RESUMO

The aging lung is associated with increased susceptibility to chronic inflammatory diseases such as chronic obstructive pulmonary disease where females have been reported to be more susceptible than males. The changes in reproductive hormones due to aging may directly or indirectly affect lung structure and function and little is known on the mechanism of these changes. Twenty female rhesus macaques were divided into four groups. Ovariectomy (OVX) was performed on eight animals with three receiving estrogen/progesterone therapy (HRT) and five animals given implants containing vehicle. The remaining 12 animals represented control groups of ages 10-14 years (n = 6) and ages 20-24 (n = 6). A design-based stereological method was employed to estimate the number of alveoli in the right middle lung lobe along with hormone analysis for possible correlation. A significant decrease was found in the number of alveoli in the vehicle OVX animals compared to intact younger adult females (P < 0.001). A significant increase in alveoli between OVX vehicle animals and those on HRT was also found (P < 0.0001). There was difference in the number of alveoli between younger adult animals and animals on HRT. The loss of ovaries and hormones had a significant effect on alveolar lung morphology. This result mimics what is seen in the aging process and could contribute to gender differences reported in the elderly. Hormone replacement, as reported here, could possibly slow the loss of alveoli due to the aging process or aid in alveolar regeneration through direct or indirect mechanisms. Anat Rec, 299:973-978, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Envelhecimento/efeitos dos fármacos , Estrogênios/farmacologia , Terapia de Reposição Hormonal , Progesterona/farmacologia , Alvéolos Pulmonares/fisiologia , Animais , Feminino , Macaca mulatta , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/efeitos dos fármacos
5.
Neurobiol Aging ; 34(7): 1882-90, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23369546

RESUMO

Preclinical studies in aged, surgically-menopausal rhesus monkeys have revealed powerful benefits of intermittent estrogen injections on prefrontal cortex-dependent working memory, together with corresponding effects on dendritic spine morphology in the prefrontal cortex. This contrasts with the inconsistent effects of hormone therapy (HT) reported in clinical studies in women. Factors contributing to this discrepancy could include differences in the formulation and sequence of HT regimens, resulting in different neurobiological outcomes. The current study evaluated, in aging surgically menopausal rhesus monkeys, the cognitive effects of 4 HT regimens modeled directly on human clinical practice, including continuous estrogen treatment opposed by progesterone. None of the regimens tested produced any cognitive effect, despite yielding physiologically relevant serum hormone levels, as intended. These findings have implications for the design of regimens that might optimize the benefits of hormone treatment for healthy aging, and suggest that common HT protocols used by women may fail to result in substantial cognitive benefit, at least via direct effects on the prefrontal cortex.


Assuntos
Envelhecimento/efeitos dos fármacos , Envelhecimento/psicologia , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/psicologia , Estradiol/administração & dosagem , Terapia de Reposição de Estrogênios/métodos , Ovariectomia , Envelhecimento/sangue , Animais , Transtornos Cognitivos/sangue , Implantes de Medicamento , Estradiol/sangue , Feminino , Humanos , Macaca mulatta
6.
Menopause ; 20(3): 322-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23435030

RESUMO

OBJECTIVE: Circulating adrenal steroids rise during the menopausal transition in most middle-aged women and may contribute to differences in between-women symptoms and ultimate health outcomes. However, the mechanisms for this shift in adrenal steroid production in middle-aged women are not known. This study aims to determine whether hormone therapy (HT) for 1 year can modulate adrenal androgen production. METHODS: Younger (9.8 [0.4] years, n = 20) and older (22.7 [0.4] years, n = 37) female laboratory macaques were ovariectomized, and each group was treated with different regimens of HT for up to 1 year. Changes in adrenal histology and circulating adrenal androgens were monitored after estrogen-alone (E) or estrogen plus progesterone (E + P) treatment, and these changes were compared with the same measures in similarly aged animals given vehicle. RESULTS: Zona reticularis area, serum dehydroepiandrosterone (DHEA), and serum dehydroepiandrosterone sulfate (DHEAS) were higher in younger vehicle-treated animals compared with older vehicle-treated animals (P < 0.02). Both E and E + P treatments decreased circulating DHEAS in the younger group (P < 0.05). Although E treatment also decreased DHEAS in the older group, this was not statistically significant. In contrast, E + P treatment in the older group resulted in a rise in DHEAS over vehicle, which was significantly higher than the results of E treatment (P < 0.01). Circulating concentrations of DHEA exhibited similar trends, but these changes did not reach statistical significance. CONCLUSIONS: These data demonstrate that intervention with ovarian steroids can modulate adrenal androgen production in female higher primates and that both animal age and type of HT regimen determine adrenal response.


Assuntos
Glândulas Suprarrenais/metabolismo , Androgênios/metabolismo , Terapia de Reposição de Estrogênios , Macaca mulatta/fisiologia , Menopausa/fisiologia , Progesterona/administração & dosagem , Glândulas Suprarrenais/efeitos dos fármacos , Envelhecimento , Androstenodiol/sangue , Animais , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Terapia de Reposição de Estrogênios/métodos , Feminino , Modelos Animais , Ovariectomia , Zona Reticular/anatomia & histologia
7.
Menopause ; 20(3): 329-35, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23435031

RESUMO

OBJECTIVE: We propose that the adrenal gland of an older higher primate female animal model will respond to human chorionic gonadotropin (hCG) hormone challenge by secreting additional dehydroepiandrosterone sulfate (DHEAS). Such a response in surgically and chemically castrated animals will provide proof of concept and a validated animal model for future studies to explore the rise in DHEAS during the menopausal transition of women. METHODS: Twenty-four 18- to 26-year-old female cynomolgus monkeys were screened for ovarian function and then either ovariectomized (n = 4) or treated with a gonadotropin-releasing hormone agonist (GnRHa; n = 20) to block ovarian steroid production. After a recovery period from surgical procedure or down-regulation, a single-dose challenge (1,000 IU/animal, IM) of hCG was then administered to determine if luteinizing hormone (LH)/chorionic gonadotropin could accelerate circulating DHEAS production. Serum DHEAS, bioactive LH, and urinary metabolites of ovarian sex steroids were monitored before, during, and after these treatments. RESULTS: Circulating LH bioactivity and immunoreactive DHEAS concentrations were suppressed in all animals 14 days postadministration of GnRHa. Urinary metabolites of estradiol and progesterone remained low after the surgical procedure or a flare reaction to GnRHa. Circulating DHEAS levels were increased after hCG administration, and the increase in individual animals was proportional to the pretreatment DHEAS at baseline. Circulating DHEAS concentrations were positively correlated to endogenous LH bioactive concentrations prior to hCG challenge and were subsequently further elevated by the hCG challenge while no concomitant change in ovarian steroid hormone excretion was observed. CONCLUSIONS: These data demonstrate a positive adrenal androgen response to LH/chorionic gonadotropin in older female higher primates and suggest a mechanism for the rise in adrenal androgen production during the menopausal transition in women. These results also illustrate that the nonhuman primate animal model can be effectively used to investigate this phenomenon.


Assuntos
Envelhecimento/fisiologia , Gonadotropina Coriônica/farmacologia , Sulfato de Desidroepiandrosterona/sangue , Hormônio Luteinizante/biossíntese , Macaca fascicularis/fisiologia , Menopausa/fisiologia , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/fisiologia , Animais , Gonadotropina Coriônica/sangue , Estradiol/urina , Feminino , Hormônio Liberador de Gonadotropina/agonistas , Leuprolida/administração & dosagem , Hormônio Luteinizante/sangue , Modelos Animais , Ovariectomia , Progesterona/urina
8.
J Neurosci ; 32(34): 11700-5, 2012 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-22915112

RESUMO

Preclinical animal models have provided strong evidence that estrogen (E) therapy (ET) enhances cognition and induces spinogenesis in neuronal circuits. However, clinical studies have been inconsistent, with some studies revealing adverse effects of ET, including an increased risk of dementia. In an effort to bridge this disconnect between the preclinical and clinical data, we have developed a nonhuman primate (NHP) model of ET combined with high-resolution dendritic spine analysis of dorsolateral prefrontal cortical (dlPFC) neurons. Previously, we reported cyclic ET in aged, ovariectomized NHPs increased spine density on dlPFC neurons. Here, we report that monkeys treated with cyclic E treatment paired with cyclic progesterone (P), continuous E combined with P (either cyclic or continuous), or unopposed continuous E failed to increase spines on dlPFC neurons. Given that the most prevalent form of ET prescribed to women is a combined and continuous E and P, these data bring into convergence the human neuropsychological findings and preclinical neurobiological evidence that standard hormone therapy in women is unlikely to yield the synaptic benefit presumed to underlie the cognitive enhancement reported in animal models.


Assuntos
Envelhecimento/efeitos dos fármacos , Espinhas Dendríticas/efeitos dos fármacos , Estrogênios/farmacologia , Neurônios/citologia , Córtex Pré-Frontal/citologia , Progesterona/farmacologia , Envelhecimento/patologia , Análise de Variância , Animais , Estrogênios/sangue , Feminino , Macaca mulatta , Microscopia Confocal , Neurônios/efeitos dos fármacos , Ovariectomia , Córtex Pré-Frontal/efeitos dos fármacos , Progesterona/sangue
9.
Menopause ; 19(6): 650-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22415563

RESUMO

OBJECTIVE: The perimenopausal increase in circulating dehydroepiandrosterone sulfate (DHEAS) levels during the menopausal transition (MT) is accompanied by other adrenal steroids that have the potential to alter estrogen/androgen balance and explain the wide interwoman range of estrogen-related symptoms experienced during the MT. METHODS: Annual serum samples from the Study of Women's Health Across the Nation, which had previously been analyzed for immunoreactive estradiol (E2), testosterone, DHEAS, and sex hormone-binding globulin, were selected based on DHEAS concentration and analyzed for immunoreactive and bioactive estrogens and androgens, including immunoreactive androstenedione, dehydroepiandrosterone, and 5-androstene-3ß,17ß-diol (androstenediol [Adiol]). RESULTS: A two-fold increase in circulating androstenedione and testosterone was found to rise in parallel with the rise in circulating DHEAS, whereas dehydroepiandrosterone and Adiol concentrations rose seven- to eight-fold. Circulating Adiol, which has both androgenic and estrogenic biological activity, was significantly associated (P < 0.02) with circulating estrogen bioactivity only when E2 concentrations were low and Adiol levels were high. CONCLUSIONS: The wide range of circulating levels of Adiol and its contribution to total circulating estrogenicity during the MT is consistent with the observed interwoman difference in symptoms at this time. Therefore, we conclude that Adiol contributes to circulating estrogenicity when E2 production falls at menopause and may contribute significantly to the endocrine changes experienced by midlife women.


Assuntos
Androstenodiol/sangue , Estradiol/sangue , Perimenopausa/sangue , Adulto , Androstenodiona/sangue , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Testosterona/sangue
10.
Menopause ; 19(6): 658-63, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22415570

RESUMO

OBJECTIVE: It is now recognized that mean circulating dehydroepiandrosterone sulfate (DHEAS) concentrations in most midlife women exhibit a positive inflection starting in early perimenopause, continuing through early postmenopause and returning to early perimenopausal levels by late postmenopause. This rise in mean DHEAS is accompanied by concomitant rises in testosterone (T), dehydroepiandrosteone (DHEA), and androstenedione (Adione) and an equal rise in androstenediol (Adiol). These observations suggest that there is a specific relationship between the circulating levels of steroids emanating from the adrenal glands, declining ovarian function, and the stages of the menopausal transition. This study was designed to test the hypothesis that the menopausal stage-specific change in circulating DHEAS is associated with concomitant changes in the circulating pattern of adrenal steroids and that some of these adrenal androgens could influence the circulating estrogen/androgen balance. METHODS: Stored annual serum samples (N = 120) were first selected to represent four longitudinal DHEAS profiles of individual women to assess and compare changes in the adrenal contribution to circulating steroids. RESULTS: Changes in mean circulating DHEAS levels in midlife women during the menopausal transition is associated with changes in mean circulating T, Adione, and Adiol. Mean Adione and T concentrations changed the least, whereas mean DHEAS and Adiol changed the most. CONCLUSIONS: Changes in circulating steroid hormone emanating from the adrenal during the menopausal transition may be more important than the decline in ovarian function in terms of altering the estrogen/androgen balance.


Assuntos
Glândulas Suprarrenais/metabolismo , Androgênios/sangue , Perimenopausa/sangue , Adulto , Androstenodiol/sangue , Androstenodiona/sangue , Estudos de Coortes , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Feminino , Humanos , Hidrocortisona/sangue , Estudos Longitudinais , Pessoa de Meia-Idade , Testosterona/sangue
11.
Endocrinology ; 153(3): 1063-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22294752

RESUMO

Despite the vital physiological role of endometrial regeneration during the menstrual cycle and the various pathological implications of abnormal growth of endometrial epithelial cells, the local factors and regulatory mechanisms involved in endometrial regeneration and growth have not been well characterized. Here, we examine the pattern, hormone dependence, and potential functions of Wnt7a (wingless-type MMTV integration site family member 7a), which is known to play a critical role in the formation of the mouse endometrial epithelium during embryonic development, in both human and artificially cycling rhesus macaque endometrium, and using a potent Wnt-antagonist in a mouse model of endometrial regeneration. Wnt7a transcript levels were examined using quantitative real-time PCR and in situ hybridization, and immunohistochemistry was performed to detect Ki-67 and 3,5-bromodeoxyuridine. Stringent, fully conditional Wnt inhibition was achieved by adenoviral expression of Dickkopf-1 during artificial endometrial regeneration in mice. In macaques, Wnt7a expression was confined to the newly formed luminal epithelium (LE) and upper glands during the postmenstrual repair phase. The signal increased in the LE during the proliferative phase but decreased in the upper glands and was undetectable in the glands by the late proliferative phase. Interestingly, Wnt7a was completely suppressed in the LE and remained undetectable in other cell types after 7 d of progesterone treatment. The pattern of Wnt7a expression in the human endometrium was similar to that in macaques. Blockade of Wnt signaling during endometrial regeneration in mice resulted in a dramatic delay in reepithelialization and degeneration of glands and LE. These results strongly suggest, for the first time, a role for Wnt7a in postmenstrual regeneration and proliferation of endometrial glands and LE in primates, and its dramatic suppression by progesterone is likely essential for secretory transformation of the epithelium.


Assuntos
Regulação da Expressão Gênica , Proteínas Wnt/biossíntese , Adulto , Animais , Bromodesoxiuridina/farmacologia , Modelos Animais de Doenças , Endométrio/metabolismo , Epitélio/metabolismo , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Antígeno Ki-67/biossíntese , Macaca mulatta , Ciclo Menstrual , Camundongos , Modelos Biológicos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Proteínas Wnt/metabolismo
12.
Biol Reprod ; 86(1): 1-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21918127

RESUMO

The impact of compartmental expression of steroidogenic enzymes and of changes in flux through delta5 and delta4 metabolism on sex steroid synthesis was investigated by rebuilding pathways using recombinant enzyme expression by infection of insect cells with recombinant baculovirus constructs. Human cytochromes 17alpha-hydroxylase/17,20-lyase (P450c17) and aromatase (P450arom), always coexpressed with their redox partner NADPH-P450 oxidoreductase (CPR) and 3beta-hydroxysteroid dehydrogenase/delta5-4 isomerase (3betaHSD; types 1 or 2), were compartmentally expressed in different cell populations or coexpressed together with pregnenolone (100 nM) as substrate. Estrone was compared among cell compartments expressing different enzyme combinations or in cells coexpressing all enzymes (experiment 1). Additionally, P450c17, 3betaHSD, and CPR were all coexpressed, and androstenedione was measured in cells with different 3betaHSD expression levels or activity using an inhibitor, trilostane (experiment 2). Steroids were measured by immunoassay and mass spectrometry. In experiment 1, partitioning of P450c17, P450arom, and 3betaHSD markedly decreased estrone synthesis in comparison to cells coexpressing enzymes in different combinations. However, partitioning P450arom with 3betaHSD from P450c17 in different cell populations resulted in more estrone than either of the other two-cell compartment models. In experiment 2 (cells coexpressing P450c17, 3betaHSD, and CPR), androstenedione secretion was (paradoxically) higher at lower levels of 3betaHSD, and partial inhibition of 3betaHSD by trilostane also increased androstenedione when 3betaHSD expression was high. We conclude 1) that tissue or cell-specific, partitioned expression of sex steroid synthesizing enzymes limits rather than maximizes estrogen synthesis and 2) that limiting metabolism by 3betaHSD can paradoxically promote androgen synthesis when 3betaHSD expression is high by promoting delta5-steroid flux.


Assuntos
Androgênios/biossíntese , Sistema Enzimático do Citocromo P-450/metabolismo , Estrogênios/biossíntese , Regulação Enzimológica da Expressão Gênica/fisiologia , 17-alfa-Hidroxiprogesterona/metabolismo , Animais , Linhagem Celular , Sistema Enzimático do Citocromo P-450/genética , Feminino , Células da Granulosa/metabolismo , Humanos , Insetos , Isoformas de Proteínas , Proteínas Recombinantes , Especificidade por Substrato
13.
Obstet Gynecol Clin North Am ; 38(3): 467-75, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21961714

RESUMO

The concept that adrenal androgen production gradually declines with age has changed after analysis of longitudinal data from the Study of Women's Health Across the Nation (SWAN). It is now recognized that 4 adrenal androgens rise during the menopausal transition in most women. Ethnic and individual differences in sex steroids are more apparent in circulating adrenal steroids than in either estradiol or cyclic ovarian steroid hormone profiles, particularly during the early and late perimenopause. Thus, adrenal steroid production may play a larger role in the occurrence of symptoms and the potential for healthier aging than previously recognized.


Assuntos
Corticosteroides/sangue , Glândulas Suprarrenais/metabolismo , Androgênios/sangue , Perimenopausa/sangue , Androstenodiol/sangue , Sulfato de Desidroepiandrosterona/sangue , Feminino , Humanos , Testosterona/sangue
14.
Reprod Sci ; 18(2): 119-27, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20889956

RESUMO

Triclocarban (TCC; 3,4,4'-trichlorocarbanilide) is an antimicrobial agent used widely in various personal hygiene products including soaps. Recently, TCC has been shown to enhance testosterone-induced effects in vitro and to enlarge accessory sex organs in castrated male rats. This study was designed to evaluate the effects of TCC on intact age-matched male rats and on human prostate LNCaP and C4-2B cells. Seven-week-old male Sprague-Dawley rats received either a normal diet or a diet supplemented with TCC (0.25% in diet) for 10 days. Triclocarban induced hyperplasia of accessory sex organs in the absence of significant qualitative histological changes. Serum luteinizing hormone (LH) and testosterone were not significantly altered by TCC treatment. In prostate cancer-derived LNCaP and C4-2B cells, TCC potentiated androgen actions via androgen receptor-dependent actions. In conclusion, TCC significantly affects intact male reproductive organs and potentiates androgen effects in prostate cancer cells.


Assuntos
Anti-Infecciosos Locais/toxicidade , Carbanilidas/toxicidade , Hormônio Luteinizante/sangue , Próstata/efeitos dos fármacos , Testosterona/sangue , Animais , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Próstata/patologia , Próstata/fisiopatologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/fisiopatologia , Ratos , Ratos Sprague-Dawley , Receptores Androgênicos/metabolismo , Maturidade Sexual/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Água/metabolismo
15.
Am J Epidemiol ; 171(11): 1203-13, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20427327

RESUMO

The effect of change in reproductive hormones and menopause on incident obesity (body mass index > or =30 kg/m(2)) and severe obesity (body mass index > or =35 kg/m(2)) was evaluated over 9 years in 3,260 US women recruited in the multiethnic Study of Women's Health Across the Nation in 1996-1997. After 9 years, cumulative incidences of obesity and severe obesity reached 21.8% and 12.3%, respectively. In multivariate analysis, hormone changes, chronic health conditions, lower physical activity, race/ethnicity, and age were significantly associated with incident obesity and/or severe obesity. The odds of incident severe obesity increased with surgical menopause (odds ratio (OR) = 5.07, 95% confidence interval (CI): 2.29, 11.20; P < 0.001) and initiation of hormone therapy prior to 12 months of amenorrhea (OR = 2.94, 95% CI: 1.14, 7.58; P = 0.03). Predictors of obesity included an increase in free androgen index (OR = 1.37, 95% CI: 1.12, 1.68; P = 0.002) and a decrease in sex hormone-binding globulin (OR = 0.60, 95% CI: 0.45, 0.80; P = 0.0005). Similar results were found for severe obesity. Obesity rates varied by race, but no hormone-by-race interactions were observed. These longitudinal data demonstrate that higher androgens, lower sex hormone-binding globulin, surgical menopause, and early hormone therapy use predict incident obesity and/or severe obesity in a multiracial cohort of women transitioning into menopause.


Assuntos
Hormônios Esteroides Gonadais/sangue , Obesidade/sangue , Fatores Etários , Amenorreia/complicações , Índice de Massa Corporal , Intervalos de Confiança , Estudos Transversais , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Hormônios Esteroides Gonadais/fisiologia , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Estudos Longitudinais , Menopausa/fisiologia , Análise Multivariada , Obesidade/epidemiologia , Obesidade/etiologia , Obesidade/fisiopatologia , Obesidade Mórbida/sangue , Obesidade Mórbida/epidemiologia , Obesidade Mórbida/etiologia , Obesidade Mórbida/fisiopatologia , Razão de Chances , Prevalência , Grupos Raciais , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue , Estados Unidos/epidemiologia
16.
J Clin Endocrinol Metab ; 94(8): 2945-51, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19470626

RESUMO

CONTEXT: A previous report from the Study of Women Across the Nation indicated a rise in dehydroepiandrosterone sulfate (DHEAS) during the menopausal transition using data from three annual visits. OBJECTIVE: Our objective was to examine changes in DHEAS with chronological and ovarian aging, expanding the original analyses to include 10 yr of annual data. DESIGN: A longitudinal observational study and cross-sectional analyses of baseline data were conducted. OUTCOME MEASURES AND SUBJECTS: DHEAS, age, menopause status, ethnicity, smoking, weight, and height were assessed in 2886 women from five ethnic groups aged 42-52 yr at entry. Hysterectomy, bilateral oophorectomy, and hormone use were excluded. RESULTS: Cross-sectional analysis at baseline showed a linear decline in circulating log-transformed DHEAS with increasing age for either the entire cohort (2.81% per year) or for individual ethnicities. A similar negative association with baseline age (2.44% decline per year) was seen in longitudinal linear mixed modeling including observations from premenopause through late postmenopause, an additional 0.33% decline/year. In contradistinction, a late-transition rise in DHEAS was detected when the same women were analyzed by ovarian status. The average increase in mean circulating DHEAS level between early and late menopause transition, beyond changes predicted by aging, was 3.95%, followed by an average decline of 3.96% during the late postmenopause. Approximately 84.5% of the women had an estimated within-woman increase in DHEAS from premenopause/early perimenopause to late perimenopause/early postmenopause. CONCLUSION: These observations underscore differences between cross-sectional and longitudinal studies and the importance of considering ovarian status. Additional investigations regarding adrenal contribution to sex steroids in mid-aged women are warranted.


Assuntos
Sulfato de Desidroepiandrosterona/sangue , Menopausa/sangue , Adulto , Negro ou Afro-Americano , Envelhecimento/sangue , Povo Asiático , Estudos Transversais , Desidroepiandrosterona/sangue , Feminino , Hispânico ou Latino , Humanos , Estudos Longitudinais , Hormônio Luteinizante/sangue , Pessoa de Meia-Idade
17.
Arch Intern Med ; 168(19): 2146-53, 2008 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-18955645

RESUMO

BACKGROUND: The "timing hypothesis," in addressing findings from the Women's Health Initiative trial, suggests that hormone therapy (HT) should be initiated within 6 years of the menopause transition to extend a favorable estrogenic environment after menopause. METHODS: We compared sex steroid and cardiovascular profiles at the 5-year follow-up visit in a community-based, longitudinal study of the menopause transition (Study of Women's Health Across the Nation). Women aged 47 to 57 years were in 1 of 4 groups: premenopausal, women using conjugated equine estrogen with or without progestin, or postmenopausal (<5 years) without HT use. Cardiovascular assays included low-density lipoprotein cholesterol, oxidized low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, apolipoproteins A-I and B, F(2a)-isoprostanes, C-reactive protein, and lipoprotein (a)-1. Sex steroid assays were performed for estradiol, estrogen receptor ligand load, 2-hydroxyestrone, 16alpha-hydroxyestrone, total testosterone, and sex hormone-binding globulin. RESULTS: Users of HT had 50% higher levels of sex hormone-binding globulin (P < .001 for both HT groups), which limits binding of sex steroids to their receptors, and higher excreted estrone metabolites (more than 60%; P < .001 for both HT groups) than premenopausal or postmenopausal women. These findings were, in turn, associated with higher levels of F(2a)-isoprostanes, an oxidative stress measure, than in premenopausal women. The HT users had a more favorable ratio of high-density to low-density lipoprotein cholesterol than did premenopausal or postmenopausal women (P < .01), but higher triglyceride levels (P < .01). CONCLUSION: Although HT users had some more favorable lipid profiles than premenopausal and postmenopausal women, there was evidence of adverse HT effects even in women free of atherosclerosis studied within the approximate 6-year period proposed with the timing hypothesis.


Assuntos
Colesterol/sangue , Terapia de Reposição de Estrogênios , Estrogênios/sangue , Hormônios Esteroides Gonadais/sangue , Menopausa/sangue , Progestinas/administração & dosagem , Adulto , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Estrogênios/administração & dosagem , F2-Isoprostanos/sangue , Feminino , Hormônios Esteroides Gonadais/administração & dosagem , Humanos , Pessoa de Meia-Idade , Globulina de Ligação a Hormônio Sexual/metabolismo , Fatores de Tempo
18.
Environ Health Perspect ; 116(9): 1203-10, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18795164

RESUMO

BACKGROUND: Concerns have been raised about the biological and toxicologic effects of the antimicrobials triclocarban (TCC) and triclosan (TCS) in personal care products. Few studies have evaluated their biological activities in mammalian cells to assess their potential for adverse effects. OBJECTIVES: In this study, we assessed the activity of TCC, its analogs, and TCS in in vitro nuclear-receptor-responsive and calcium signaling bioassays. MATERIALS AND METHODS: We determined the biological activities of the compounds in in vitro, cell-based, and nuclear-receptor-responsive bioassays for receptors for aryl hydrocarbon (AhR), estrogen (ER), androgen (AR), and ryanodine (RyR1). RESULTS: Some carbanilide compounds, including TCC (1-10 muM), enhanced estradiol (E(2))-dependent or testosterone-dependent activation of ER- and AR-responsive gene expression up to 2.5-fold but exhibited little or no agonistic activity alone. Some carbanilides and TCS exhibited weak agonistic and/or antagonistic activity in the AhR-responsive bioassay. TCS exhibited antagonistic activity in both ER- and AR-responsive bioassays. TCS (0.1-10 muM) significantly enhanced the binding of [(3)H]ryanodine to RyR1 and caused elevation of resting cytosolic [Ca(2+)] in primary skeletal myotubes, but carbanilides had no effect. CONCLUSIONS: Carbanilides, including TCC, enhanced hormone-dependent induction of ER- and AR-dependent gene expression but had little agonist activity, suggesting a new mechanism of action of endocrine-disrupting compounds. TCS, structurally similar to noncoplanar ortho-substituted poly-chlorinated biphenyls, exhibited weak AhR activity but interacted with RyR1 and stimulated Ca(2+) mobilization. These observations have potential implications for human and animal health. Further investigations are needed into the biological and toxicologic effects of TCC, its analogs, and TCS.


Assuntos
Antibacterianos/farmacologia , Carbanilidas/farmacologia , Triclosan/farmacologia , Animais , Bioensaio , Humanos , Técnicas In Vitro , Modelos Moleculares , Receptores de Superfície Celular/efeitos dos fármacos , Células Tumorais Cultivadas
19.
Arch Intern Med ; 168(14): 1568-75, 2008 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-18663170

RESUMO

BACKGROUND: Cross-sectional studies suggest that prevalence of the metabolic syndrome (MetS) increases from premenopause to postmenopause in women, independent of age. Little is known about why. We hypothesized that the incidence of the MetS increases with progression through menopause and that this increase is explained by the progressive androgenicity of the hormonal milieu. METHODS: This longitudinal, 9-year study of 949 participants in the Study of Women's Health Across the Nation investigates the natural history of the menopausal transition. Participants of 5 ethnicities at 7 geographic sites were recruited when they were premenopausal or early perimenopausal and were eligible for this study if they (1) reached menopause during the study; (2) had never taken hormone therapy, and (3) did not have diabetes mellitus or the MetS at baseline. The primary outcome was the presence of MetS using National Cholesterol Education Program Adult Treatment Panel III criteria. Secondary outcomes were the components of the MetS. RESULTS: By the final menstrual period, 13.7% of the women had new-onset MetS. Longitudinal analyses, centered at the final menstrual period, were adjusted for age at menopause, ethnicity, study site, marital status, education, body mass index, smoking, and aging. Odds of developing the MetS per year in perimenopause were 1.45 (95% confidence interval, 1.35-1.56); after menopause, 1.24 (95% confidence interval, 1.18-1.30). These odds were significantly different (P < .001). An increase in bioavailable testosterone or a decrease in sex hormone-binding globulin levels increased the odds. CONCLUSIONS: As testosterone progressively dominates the hormonal milieu during the menopausal transition, the prevalence of MetS increases, independent of aging and other important covariates. This may be a pathway by which cardiovascular disease increases during menopause.


Assuntos
Menopausa , Síndrome Metabólica/epidemiologia , Saúde da Mulher , Intervalos de Confiança , Estudos Transversais , Feminino , Seguimentos , Humanos , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Morbidade/tendências , Razão de Chances , Estudos Retrospectivos , Fatores de Risco , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue , Estados Unidos/epidemiologia
20.
Endocrinology ; 149(3): 1173-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18048496

RESUMO

Many xenobiotics have been associated with endocrine effects in a wide range of biological systems. These associations are usually between small nonsteroid molecules and steroid receptor signaling systems. In this report, triclocarban (TCC; 3,4,4'-trichlorocarbanilide), a common ingredient in personal care products that is used as an antimicrobial agent was evaluated and found to represent a new category of endocrine-disrupting substance. A cell-based androgen receptor-mediated bioassay was used to demonstrate that TCC and other urea compounds with a similar structure, which have little or no endocrine activity when tested alone, act to enhance testosterone (T)-induced androgen receptor-mediated transcriptional activity in vitro. This amplification effect of TCC was also apparent in vivo when 0.25% TCC was added to the diet of castrated male rats that were supported by exogenous testosterone treatment for 10 d. All male sex accessory organs increased significantly in size after the T+TCC treatment, compared with T or TCC treatments alone. The data presented here suggest that the bioactivity of endogenous hormones may be amplified by exposure to commercial personal care products containing sufficient levels of TCC.


Assuntos
Anti-Infecciosos Locais/farmacologia , Carbanilidas/farmacologia , Disruptores Endócrinos/farmacologia , Genitália Masculina/efeitos dos fármacos , Próstata/efeitos dos fármacos , Testosterona/farmacologia , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Sinergismo Farmacológico , Genitália Masculina/patologia , Humanos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Próstata/patologia , Ratos , Ratos Sprague-Dawley , Receptores Androgênicos/metabolismo
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