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1.
J Neuroendocrinol ; 33(12): e13058, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34748236

RESUMO

Prenatal exposure to excess androgens is associated with the development of polycystic ovary syndrome (PCOS). In prenatally androgenised (PNA) mice, a model of PCOS, progesterone receptor (PR) protein expression is reduced in arcuate nucleus (ARC) GABA neurons. This suggests a mechanism for PCOS-related impaired steroid hormone feedback and implicates androgen excess with respect to inducing transcriptional repression of the PR-encoding gene Pgr in the ARC. However, the androgen sensitivity of ARC neurons and the relative gene expression of PRs over development and following prenatal androgen exposure remain unknown. Here, we used a quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) of microdissected ARC to determine the relative androgen receptor (Ar) and progesterone receptor (Pgr) gene expression in PNA and control mice at five developmental timepoints. In a two-way analysis of variance, none of the genes examined showed expression changes with a statistically significant interaction between treatment and age, although PgrA showed a borderline interaction. For all genes, there was a statistically significant main effect of age on expression levels, reflecting a general increase in expression with increasing age, regardless of treatment. For PgrB and Ar, there was a statistically significant main effect of treatment, indicating a change in expression following PNA (increased for PgrB and decreased for Ar), regardless of age. For PgrA, there was a borderline main effect of treatment, suggesting a possible change in expression following PNA, regardless of age. PgrAB gene expression changes showed no significant main effect of treatment. We additionally examined androgen and progesterone responsiveness specifically in P60 ARC GABA neurons using RNAScope® (Advanced Cell Diagnostics, Inc.) in situ hybridization. This analysis revealed that Pgr and Ar were expressed in the majority of ARC GABA neurons in normal adult females. However, our RNAScope® analysis did not show significant changes in Pgr or Ar expression within ARC GABA neurons following PNA. Lastly, because GABA drive to gonadotropin-releasing hormone neurons is increased in PNA, we hypothesised that PNA mice would show increased expression of glutamic acid decarboxylase (GAD), the rate-limiting enzyme in GABA production. However, the RT-qPCR showed that the expression of GAD encoding genes (Gad1 and Gad2) was unchanged in adult PNA mice compared to controls. Our findings indicate that PNA treatment can impact Pgr and Ar mRNA expression in adulthood. This may reflect altered circulating steroid hormones in PNA mice or PNA-induced epigenetic changes in the regulation of Pgr and Ar gene expression in ARC neurons.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Efeitos Tardios da Exposição Pré-Natal/genética , Receptores Androgênicos/genética , Receptores de Progesterona/genética , Virilismo , Animais , Animais Recém-Nascidos , Núcleo Arqueado do Hipotálamo/crescimento & desenvolvimento , Embrião de Mamíferos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Crescimento e Desenvolvimento/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Androgênicos/metabolismo , Receptores de Progesterona/metabolismo , Virilismo/embriologia , Virilismo/genética , Virilismo/metabolismo
2.
Endocrinology ; 154(5): 1921-33, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23546603

RESUMO

Prenatal androgenization induces a polycystic ovary syndrome-like phenotype in adult female offspring, which is associated with alterations that can be detected in the fetal ovary, suggesting gestational origins of this condition. We therefore investigated whether increased prenatal androgen exposure also altered testicular development using ovine animal models. Biweekly maternal testosterone propionate (TP; 100 mg) from day 62 to day 70/day 90 of gestation altered male developmental trajectory. In male fetuses serum LH was decreased (P < .01), and testicular STAR, CYP11, and CYP17 abundance were reduced. Coincident with this, basal testicular T synthesis was decreased in vitro (P < .001). Leydig cell distribution was severely perturbed in all testes prenatally exposed to TP (P < .001). To examine the contribution of estrogens, fetuses were injected with TP (20 mg), the potent estrogen agonist, diethylstilbestrol (DES; 20 mg), or vehicle control at day 62 and day 82 and assessed at day 90. The effects of fetal (direct) TP treatment, but not DES, paralleled maternal (indirect) TP exposure, supporting a direct androgen effect. Cessation of maternal androgenization at day 102 returned Leydig cell distribution to normal but increased basal T output, at day 112, demonstrating Leydig cell developmental plasticity. Earlier maternal androgen exposure from day 30 similarly influenced Leydig cell development at day 90 but additionally affected the expression of Sertoli and germ cell markers. We show in this study that increased prenatal androgen exposure alters development and function of Leydig cells at a time when androgen production is paramount for male development. This supports the concept that gestational antecedents associated with polycystic ovary syndrome may have effects on the male fetus.


Assuntos
Androgênios/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Testículo/efeitos dos fármacos , Testículo/embriologia , Androgênios/sangue , Androgênios/farmacologia , Animais , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Feto/efeitos dos fármacos , Masculino , Exposição Materna/efeitos adversos , Concentração Osmolar , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Diferenciação Sexual/efeitos dos fármacos , Ovinos , Virilismo/sangue , Virilismo/embriologia
3.
Horm Behav ; 55(5): 633-45, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19446080

RESUMO

After proposing the organizational hypothesis from research in prenatally androgenized guinea pigs (Phoenix, C.H., Goy, R.W., Gerall, A.A., Young, W.C., 1959. Organizational action of prenatally administered testosterone propionate on the tissues mediating mating behavior in the female guinea pig. Endocrinology 65, 369-382.), the same authors almost immediately extended the hypothesis to a nonhuman primate model, the rhesus monkey. Studies over the last 50 years have verified that prenatal androgens have permanent effects in rhesus monkeys on the neural circuits that underlie sexually dimorphic behaviors. These behaviors include both sexual and social behaviors, all of which are also influenced by social experience. Many juvenile behaviors such as play, mounting, and vocal behaviors are masculinized and/or defeminized, and aspects of adult sexual behavior are both masculinized (e.g. approaches, sex contacts, and mounts) and defeminized (e.g. sexual solicits). Different behavioral endpoints have different periods of maximal susceptibility to the organizing actions of prenatal androgens. Aromatization is not important, as both testosterone and dihydrotestosterone are equally effective in rhesus monkeys. Although the full story of the effects of prenatal androgens on sexual and social behaviors in the rhesus monkey has not yet completely unfolded, much progress has been made. Amazingly, a large number of the inferences drawn from the original 1959 study have proved applicable to this nonhuman primate model.


Assuntos
Androgênios/fisiologia , Comportamento Animal/fisiologia , Encéfalo/embriologia , Efeitos Tardios da Exposição Pré-Natal , Diferenciação Sexual/fisiologia , Virilismo/embriologia , Animais , Encéfalo/fisiologia , Período Crítico Psicológico , Feminino , Desenvolvimento Fetal/fisiologia , Genitália/embriologia , Genitália/fisiologia , Macaca mulatta , Masculino , Gravidez , Caracteres Sexuais , Comportamento Sexual Animal/fisiologia , Comportamento Social
4.
Rev Invest Clin ; 59(1): 73-81, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-17569302

RESUMO

Different perturbations during fetal and postnatal development unleash endocrine adaptations that permanently alter metabolism, increasing the susceptibility to develop later disease, process known as "developmental programming." Endocrine disruptor compounds (EDC) are widely spread in the environment and display estrogenic, anti-estrogenic or anti-androgenic activity; they are lipophilic and stored for long periods in the adipose tissue. Maternal exposure to EDC during pregnancy and lactation produces the exposure of the fetus and neonate through placenta and breast milk. Epidemiological and experimental studies have demonstrated reproductive alterations as a consequence of intrauterine and/or neonatal exposure to EDC. Diethystilbestrol (DES) is the best documented compound, this synthetic estrogen was administered to pregnant women in the 1950s and 1960s to prevent miscarriage. It was implicated in urogenital abnormalities in children exposed in utero and was withdrawn from the market. The "DES daughters" are women with high incidence of vaginal hypoplasia, spontaneous abortion, premature delivery, uterine malformation, menstrual abnormalities and low fertility. The "DES sons" show testicular dysgenesis syndrome, which is characterized by hypospadias, cryptorchidism and low semen quality. This entity is also associated wtih fetal exposure to anti-androgens as flutamide. The effects on the reproductive axis depend on the stage of development and the window of exposure, as well as the dose and the compound. The wide distribution of EDC into the environment affects both human health and ecosystems in general, the study of their mechanisms of action is extremely important currently.


Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Disruptores Endócrinos/efeitos adversos , Genitália/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Anormalidades Induzidas por Medicamentos/epidemiologia , Adulto , Antagonistas de Androgênios/efeitos adversos , Antagonistas de Androgênios/farmacologia , Animais , Mama/embriologia , Dietilestilbestrol/efeitos adversos , Dietilestilbestrol/farmacologia , Dietilestilbestrol/uso terapêutico , Dioxinas/efeitos adversos , Desenvolvimento Embrionário/efeitos dos fármacos , Disruptores Endócrinos/farmacologia , Antagonistas de Estrogênios/efeitos adversos , Antagonistas de Estrogênios/farmacologia , Estrogênios/agonistas , Feminino , Feminização/induzido quimicamente , Feminização/embriologia , Genitália/anormalidades , Genitália/embriologia , Humanos , Hipotálamo/anormalidades , Hipotálamo/efeitos dos fármacos , Hipotálamo/embriologia , Masculino , Glândulas Mamárias Animais/embriologia , Leite Humano/química , Ácidos Ftálicos/efeitos adversos , Fitoestrógenos/efeitos adversos , Fitoestrógenos/farmacologia , Fitoestrógenos/uso terapêutico , Gravidez , Ratos , Virilismo/induzido quimicamente , Virilismo/embriologia
5.
Rev. invest. clín ; 59(1): 73-81, ene.-feb. 2007. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-632393

RESUMO

Different perturbations during fetal and post natal development unleash endocrine adaptations that permanently alter metabolism, increasing the susceptibility to develop later disease, process known as "developmental programming"'. Endocrine disruptor compounds (EDC) are widely spread on the environment and display estrogenic, anti-estrogenic or anti-androgenic activity; they are lypophilyc and stored for long periods on the adipose tissue. Maternal exposure to EDC during pregnancy and lactation produces the exposure of the fetus and neonate through placenta and breast milk. Epidemiological and experimental studies have demonstrated reproductive alterations as a consequence of intrauterine and/or neonatal exposure to EDC. Diethystilbestrol (DES) is the best documented compound, this synthetic estrogen was administered to pregnant women at the BO and 60 to prevent miscarriage. It was implicated in urogenital abnormalities in children exposed in utero and withdrawn from the market. The "DES daughters" are women with high incidence of vaginal hypoplasia, spontaneous abortion, premature delivery, uterine malformation, menstrual abnormalities and low fertility. The "DES sons" show testicular dysgenesis syndrome, which is characterized by hypospadias, cryptorchidism and low semen quality. This entity is also associated to the fetal exposure to anti-androgens as flutamide. The effects on the reproductive axis depend on the stage of development and the window of exposure, as well as the dose and the compound. The wide distribution of EDC into the environment affects both human health and ecosystems in general, the study of their mechanisms of action is extremely important currently.


Diversas perturbaciones durante el desarrollo fetal y posnatal desencadenan adaptaciones endocrinas que modifican permanentemente el metabolismo, incrementando la susceptibilidad para el desarrollo de enfermedades, proceso conocido como "programación durante el desarrollo". Los compuestos disruptores endocrinos (CDE) se encuentran en el medio ambiente y presentan actividad estrogénica, antiestrogénica o antiandrogénica; son altamente lipofílicos y se almacenan por periodos prolongados en el tejido adiposo. La exposición materna a CDE durante el embarazo y la lactancia permite su paso al producto a través de la placenta y la leche materna. Estudios epidemiológicos y experimentales han demostrado alteraciones en el eje reproductivo como consecuencia de la exposición intrauterina y/o neonatal a CDE. El compuesto mejor documentado es el dietilestilbestrol (DES), este estrógeno sintético fue administrado a mujeres embarazadas durante los 50s y 60s y retirado del mercado por su implicación en anormalidades urogenitales de los bebés expuestos in útero. Las denominadas "hijas del DES" son mujeres con alta incidencia de hipoplasia vaginal, malformaciones uterinas, irregularidades menstruales, baja fertilidad y alta prevalencia de aborto espontáneo y parto prematuro. Por su parte, "los hijos del DES" presentan una entidad clínica conocida como síndrome de disgenesia testicular caracterizado por hipospadias, criptorquidia y baja calidad del semen. Este síndrome también se asocia a la exposición fetal a compuestos antiandrogénicos como la ñutamida. Los efectos en el eje reproductivo dependen del estadio de desarrollo y del tiempo de exposición, así como de la dosis y el compuesto del que se trate. La extensa presencia de CDE en el ambiente afecta la salud humana e impacta al ecosistema en general por lo cual es de suma importancia el estudio de los mecanismos involucrados en su acción.


Assuntos
Adulto , Animais , Feminino , Humanos , Masculino , Gravidez , Ratos , Anormalidades Induzidas por Medicamentos/etiologia , Disruptores Endócrinos/efeitos adversos , Genitália/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Anormalidades Induzidas por Medicamentos/epidemiologia , Antagonistas de Androgênios/efeitos adversos , Antagonistas de Androgênios/farmacologia , Mama/embriologia , Dietilestilbestrol/efeitos adversos , Dietilestilbestrol/farmacologia , Dietilestilbestrol/uso terapêutico , Dioxinas/efeitos adversos , Desenvolvimento Embrionário/efeitos dos fármacos , Disruptores Endócrinos/farmacologia , Antagonistas de Estrogênios/efeitos adversos , Antagonistas de Estrogênios/farmacologia , Estrogênios/agonistas , Feminização/induzido quimicamente , Feminização/embriologia , Genitália/anormalidades , Genitália/embriologia , Hipotálamo/anormalidades , Hipotálamo/efeitos dos fármacos , Hipotálamo/embriologia , Glândulas Mamárias Animais/embriologia , Leite Humano/química , Ácidos Ftálicos/efeitos adversos , Fitoestrógenos/efeitos adversos , Fitoestrógenos/farmacologia , Fitoestrógenos/uso terapêutico , Virilismo/induzido quimicamente , Virilismo/embriologia
6.
Trends Endocrinol Metab ; 17(9): 349-56, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17010637

RESUMO

Female spotted hyenas (Crocuta crocuta) are the only female mammals that lack an external vaginal opening. Mating and birth take place through a urogenital canal that exits at the tip of a hypertrophied clitoris. This 'masculine' phenotype spurred a search for an alternate source of fetal androgens. Although androstenedione from the maternal ovary is readily metabolized to testosterone by the hyena placenta, formation of the penile clitoris and scrotum appear to be largely androgen independent. However, secretions from the fetal testes underlie sex differences in the genitalia and central nervous system that are essential for male reproduction. Naturally circulating androgens, acting prenatally, reduce reproductive success in adult female spotted hyenas. Effects on aggression and dominance might offset these reproductive 'costs' of female androgenization in utero.


Assuntos
Hyaenidae/embriologia , Mamíferos/embriologia , Diferenciação Sexual/fisiologia , Androgênios/fisiologia , Animais , Feminino , Genitália/fisiologia , Masculino , Modelos Biológicos , Sistema Urogenital/anatomia & histologia , Virilismo/embriologia
7.
J Clin Endocrinol Metab ; 84(9): 3129-34, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10487675

RESUMO

Congenital adrenal hyperplasia (CAH) consists of autosomal recessive disorders of cortisol biosynthesis, which in the majority of cases result from 21-hydroxylase deficiency. Another enzymatic defect causing CAH is 11beta-hydroxylase deficiency. In both forms, the resulting excessive androgen secretion causes genital virilization of the female fetus. For over 10 yr female fetuses affected with 21-hydroxylase deficiency have been safely and successfully prenatally treated with dexamethasone. We report here the first successful prenatal treatment with dexamethasone of an affected female with 11beta-hydroxylase deficiency CAH. The family had two girls affected with 1beta-hydroxylase deficiency born with severe ambiguous genitalia who were both homozygous for the T318M mutation in the CYP11B1 gene, which codes for the 11beta-hydroxylase enzyme. In the third pregnancy in this family, the female fetus was treated in utero by administering dexamethasone to the mother, starting at 5 weeks gestation. The treatment was successful, as the newborn was not virilized and had normal female external genitalia. A second family with two affected sons was also studied in preparation for a future pregnancy. We report a novel 1-bp deletion in codon 394 (R394delta1) in the CYP11B1 gene in this family.


Assuntos
Hiperplasia Suprarrenal Congênita , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Dexametasona/uso terapêutico , Glucocorticoides/uso terapêutico , Diagnóstico Pré-Natal , Virilismo/prevenção & controle , Hiperplasia Suprarrenal Congênita/genética , Amostra da Vilosidade Coriônica , Consanguinidade , Análise Mutacional de DNA , Dexametasona/administração & dosagem , Feminino , Doenças Fetais/diagnóstico , Doenças Fetais/tratamento farmacológico , Doenças Fetais/genética , Idade Gestacional , Glucocorticoides/administração & dosagem , Humanos , Masculino , Troca Materno-Fetal , Mutação de Sentido Incorreto , Linhagem , Gravidez , Esteroide 11-beta-Hidroxilase/genética , Virilismo/embriologia , Virilismo/etiologia
8.
Pediatr. día ; 12(5): 249-52, nov.-dic. 1996.
Artigo em Espanhol | LILACS | ID: lil-194972

RESUMO

El oportuno y adecuado manejo médico de la HSRV por deficiencia de la 21-OH, permite que estos pacientes sobrevivan el período de recién nacido y el primer año de vida. En la peri o pospubertad es frecuente observar signos de hiperandrogenismo que no responden al tratamiento clásico de cortisol a dosis fisiológica y qye es posible controlar con dexametasona (Dex) 0,25 a 0,50 mg nocturna sin efectos colaterales importantes. En este artículo se revisan los criterios actuales de control del tratamiento y se plantea el tratamiento prenatla, cuando existen los recursos adecuados para hacer el diagnóstico prenatal de HSRV, informándose a la madre que ya ha tenido un hijo afectado, que la terapia con Dex 20 ug/kg iniciado en la 5ta. semana de gestación permite evitar o disminuir la malformación intrauterina de los genitales externos de un feto femenino con def de 21-OH


Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Esteroide 21-Hidroxilase/deficiência , Virilismo/tratamento farmacológico , Dexametasona/uso terapêutico , Glucocorticoides/uso terapêutico , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/embriologia , Hiperplasia Suprarrenal Congênita/etiologia , Complicações na Gravidez , Diagnóstico Pré-Natal , Virilismo/diagnóstico , Virilismo/embriologia , Virilismo/etiologia
10.
J Clin Endocrinol Metab ; 58(3): 574-7, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6607266

RESUMO

The characteristic excess production of androgens in the cortisol 21-hydroxylase defect is generally considered to be secondary to ACTH stimulation of alternate pathways. Whenever a morphological examination of the adrenals has been possible in this disorder, adrenocortical hyperplasia was a constant finding. The availability of methods for the prenatal diagnosis of the 21-hydroxylase defect has made it possible to examine some of the manifestations of this disorder during fetal life. We studied a severely virilized 20-week-old aborted female fetus with the 21-hydroxylase defect whose adrenals were neither grossly enlarged nor microscopically hyperplastic. In a pregnancy at risk for congenital adrenal hyperplasia due to a 21-hydroxylase deficiency, amniocentesis was performed in the 18th week of gestation. The 21-hydroxylase defect was established by HLA typing and highly elevated levels of 17-hydroxyprogesterone, testosterone, and androstendione in amniotic fluid. After counselling, the parents, who already had a girl with the salt-wasting form of 21-hydroxylase deficiency, wished termination of the pregnancy. The aborted 20-week-old fetus was within the normal range for gestational age in weight and height. The external genitalia were ambiguous and extremely virilized, with an enlarged clitoris and fused labioscrotal folds. A urogenital sinus opened at the base of the clitoris. The internal organs were female, with a normal uterus and ovaries. Both adrenals were normal in size and weight for their gestational age. Histological examination of the adrenals revealed no abnormalities, and no hyperplasia was detectable. Thus, the adrenals in the 21-hydroxylase defect during fetal life secrete excessive amounts of androgens and cause virilization in the absence of adrenocortical hyperplasia.


Assuntos
Hiperplasia Suprarrenal Congênita/complicações , Doenças Fetais/enzimologia , Esteroide Hidroxilases/deficiência , Virilismo/enzimologia , Feminino , Doenças Fetais/genética , Doenças Fetais/patologia , Antígenos HLA/análise , Humanos , Cariotipagem , Gravidez , Virilismo/embriologia , Virilismo/patologia
11.
Endocrinol Jpn ; 25(4): 309-13, 1978 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-568545

RESUMO

A single injection of 50 microgram testosterone was given to fetal rats on day 17, 18, 19 or 20 of gestation. On day 21, the fetuses were removed from the mother under maternal ether anesthesia, and the length of the urovaginal septum was measured microscopically in female fetuses in order to assess the virilizing effect of testosterone. In fetuses treated with testosterone on day 17, the length of the urovaginal septum was comparable to that of oil-treated littermate controls. In fetuses treated on day 18, the length was significantly abridged compared with controls. In fetuses treated on day 19, the abridgment of the urovaginal septum was most marked. In fetuses treated on day 20, the length of the septum was again comparable to that of controls. The observations suggest that day 19 is the critical day for the virilizing effect of testosterone. Various amounts of testosterone and its metabolites including dihydrotestosterone, androstane-3 beta, 17beta-diol and androstane-3 alpha, 17beta-diol were injected into 19-day-old female fetuses, in order to test the dose relation to the virilizing effects of these steroids in terms of abridgment of the urovaginal septum. As a consequence, it was found that testosterone was the most effective for virilization.


Assuntos
Feto/efeitos dos fármacos , Testosterona/farmacologia , Uretra/efeitos dos fármacos , Vagina/efeitos dos fármacos , Virilismo/induzido quimicamente , Androstenodiona/farmacologia , Androsterona/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Idade Gestacional , Masculino , Gravidez , Ratos , Virilismo/embriologia
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