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1.
Mol Hum Reprod ; 17(1): 63-70, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20843821

RESUMO

Human small antral follicles (diameter 3-9 mm) were obtained from ovaries surgically removed for fertility preservation. From the individual aspirated follicles, granulosa cells and the corresponding follicular fluid were isolated in 64 follicles, of which 55 were available for mRNA analysis (24 women). Expressions of androgen receptor (AR) mRNA levels in granulosa cells, and of androstenedione and testosterone in follicular fluid, were correlated to the expression of the FSH receptor (FSHR), LH receptor (LHR), CYP19 and anti-Müllerian Hormone-receptor II (AMHRII) mRNA in the granulosa cells and to the follicular fluid concentrations of AMH, inhibin-B, progesterone and estradiol. AR mRNA expression in granulosa cells and the follicular fluid content of androgens both showed a highly significant positive association with the expression of FSHR mRNA in granulosa cells. AR mRNA expression also correlated significantly with the expression of AMHRII, but did not correlate with any of the hormones in the follicular fluid. These data demonstrate an intimate association between AR expression in immature granulosa cells, and the expression of FSHR in normal small human antral follicles and between the follicular fluid levels of androgen and FSHR expression. This suggests that follicular sensitivity towards FSH stimulation may be augmented by stimulation of androgens via the AR.


Assuntos
Androgênios/metabolismo , Líquido Folicular/metabolismo , Células da Granulosa/metabolismo , Folículo Ovariano/metabolismo , Receptores Androgênicos/genética , Receptores do FSH/genética , Adolescente , Adulto , Western Blotting , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Imuno-Histoquímica , Técnicas In Vitro , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
2.
Hum Reprod ; 26(8): 2140-5, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21593044

RESUMO

BACKGROUND: The number of germ cells in human embryonic and fetal ovaries in relation to age is currently based on volumetric estimations from one study including a total of 12 ovaries. Six recent publications present stereological estimations of the number of germ cells in ovaries and testes for the first two trimesters. METHODS: Germ cell numbers from 103 human first and second trimester gonads aged 37-133 days post-conception (p.c.), obtained after legal termination of pregnancy, were collected from six independent studies that all used similar validated stereological methods for estimating germ cell numbers as well as somatic cell numbers. RESULTS: Statistically, the six studies estimated similar number of germ cells (P > 0.05) and no interaction between the studies and age was found (P > 0.05), indicating that the increase in cell numbers in relation to age was of comparable magnitude in each study. The number of germ cells increased from a mean of 7200 to 4,933,000 in fetal ovaries and from 3700 to 1,417,000 in fetal testes, from week 5 to week 19 p.c. A higher rate of increase was found for female germ cells as compared with males (P = 0.004). During the same period, the number of somatic cells increased from a mean of 158,000 to 1,017,000 in ovaries and from 154,000 to 2,035,000 in testes, respectively. CONCLUSIONS By the use of validated stereological methods, this study provides more accurate and improved information on human germ and somatic cell numbers in ovaries and testes during the first two trimesters of pregnancy.


Assuntos
Células Germinativas/citologia , Ovário/embriologia , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Testículo/embriologia , Contagem de Células , Feminino , Humanos , Masculino , Ovário/citologia , Gravidez , Testículo/citologia
3.
Hum Reprod ; 26(8): 2129-39, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21572085

RESUMO

BACKGROUND: Conflicting results of studies on mouse and human have either verified or refuted the presence of oogonia/primordial germ cells in the post-natal ovary. The aim of this study was to trace whether oogonia recognized by immunohistochemical methods in the first trimester human ovary were present also in peri- and post-natal ovaries. METHODS: For this study, 82 human ovaries were collected: 25 from embryos from 5 to 10 weeks post conception (wpc), 2 at 18 wpc, 32 from 32 wpc to 2 years and 23 from 2 to 32 years. Of these, 80 ovaries were fixed and paraffin-embedded and 2 (8 year-old) ovaries were processed for plastic sections. Serial sections were prepared for immunohistochemical detection of markers for oogonia: tyrosine kinase receptor for stem cell factor (SCF)(C-KIT), stage-specific embryonic antigen-4 (SSEA4), homeobox gene transcription factor (NANOG), octamer binding transcription factor 4 (OCT4) and melanoma antigen-4 (Mage-A4), while noting that C-KIT also stains diplotene oocytes. RESULTS: Almost all oogonia exclusively stained for SSEA4, NANOG, OCT4 and C-KIT, whereas MAGE-A4 only stained a small fraction. At birth only a few oogonia were stained. These disappeared before 2 years, leaving only diplotene oocytes stained for C-KIT. From 18 wpc to 2 years, the medulla contained conglomerates of healthy and degenerating oogonia and small follicles, waste baskets (WBs) and oogonia enclosed in growing follicles (FWB). Medulla of older ovaries contained groups of primordial, healthy follicles. CONCLUSIONS: We found no evidence for the presence of oogonia in the human ovary after their final clearing during the first 2 years. We suggest that perinatal medullary WB and FWB give rise to the groups of small, healthy follicles in the medulla.


Assuntos
Ovário/embriologia , Ovário/crescimento & desenvolvimento , Adulto , Antígenos de Neoplasias/análise , Criança , Pré-Escolar , Feminino , Proteínas de Homeodomínio/análise , Humanos , Lactente , Proteína Homeobox Nanog , Proteínas de Neoplasias/análise , Fator 3 de Transcrição de Octâmero/análise , Oogônios , Ovário/metabolismo , Gravidez , Primeiro Trimestre da Gravidez , Proteínas Proto-Oncogênicas c-kit/análise , Antígenos Embrionários Estágio-Específicos/análise
4.
Mol Hum Reprod ; 16(9): 621-31, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20566702

RESUMO

The aim of this study was to investigate the spatiotemporal development of autonomic nerve fibers and primordial germ cells (PGCs) along their migratory route from the dorsal mesentery to the gonadal ridges in human embryos using immunohistochemical markers and electron microscopy. Autonomic nerve fibers in the dorsal mesentery, the pre-aortic and para-aortic plexuses and in the gonadal ridge were stained for beta III tubulin, neuron specific enolase and the glia fibrillary acidic protein. Electron microscopy demonstrated the presence of neurofilaments and neurotubules in these nerve fibers and their intimate contact with PGCs. PGCs expressed GAGE, MAGE-A4, OCT4 and c-Kit. Serial paraffin sections showed that most PGCs were located inside bundles of autonomic nerve fibers with the majority adjacent to the most peripheral fibers (close to Schwann cells). We also show that both nerve fibers and PGCs arrive at the gonadal ridge between 29 and 33 days pc. In conclusion, our data suggest that PGCs in human embryos preferentially migrate along autonomic nerve fibers from the dorsal mesentery to the developing gonad where they are delivered via a fine nerve plexus.


Assuntos
Sistema Nervoso Autônomo/embriologia , Movimento Celular , Células Germinativas/fisiologia , Gônadas/embriologia , Mesentério/embriologia , Fibras Nervosas/fisiologia , Células de Schwann/fisiologia , Sistema Nervoso Autônomo/química , Sistema Nervoso Autônomo/ultraestrutura , Biomarcadores/análise , Feminino , Células Germinativas/química , Células Germinativas/ultraestrutura , Idade Gestacional , Gônadas/química , Gônadas/ultraestrutura , Humanos , Imuno-Histoquímica , Mesentério/química , Mesentério/ultraestrutura , Microscopia Eletrônica , Fibras Nervosas/química , Fibras Nervosas/ultraestrutura , Ovário/embriologia , Células de Schwann/química , Células de Schwann/ultraestrutura
5.
Hum Reprod ; 25(11): 2755-61, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20823112

RESUMO

BACKGROUND: Cigarette smoking during pregnancy is associated with negative reproductive consequences for male fetuses in adult life such as reduced testicular volume and sperm concentration. The present study evaluates the number of germ and somatic cells present in human embryonic first-trimester gonads in relation to maternal smoking. METHODS: The study includes 24 human first-trimester testes, aged 37-68 days post-conception, obtained from women undergoing legal termination of pregnancy. A questionnaire was used to obtain information about smoking and drinking habits during pregnancy. Validated stereological methods were used to estimate gonadal cell numbers in histological sections. Results were also evaluated in the context of previously published data on ovaries from our laboratory. RESULTS: A significant reduction in the number of germ cells by 55% [95% confidence interval (CI) 74-21% reduction, P = 0.004] and somatic cells by 37% (95% CI 59-3%, P = 0.023) was observed in testes prenatally exposed to maternal cigarette smoking, compared with unexposed. The effect of maternal smoking was dose-dependent being higher in the heavy smokers and remained consistent after adjusting for possible confounders such as alcohol and coffee consumption (P = 0.002). The number of germ cells in embryonic gonads, irrespective of gender, was also significantly reduced by 41% (95% CI 58-19%, P = 0.001) in exposed versus non-exposed embryonic gonads. CONCLUSIONS: Prenatal exposure to maternal cigarette smoke reduces the number of germ and somatic cells in embryonic male and female gonads. This effect may have long-term consequences on the future fertility of exposed offspring. These findings may provide one potential cause of the reduced fertility observed during recent years.


Assuntos
Células Germinativas/citologia , Exposição Materna , Fumar , Testículo/citologia , Testículo/embriologia , Adulto , Feminino , Humanos , Masculino , Ovário/citologia , Ovário/enzimologia , Gravidez , Primeiro Trimestre da Gravidez , Efeitos Tardios da Exposição Pré-Natal
6.
Hum Reprod ; 24(8): 1825-33, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19429660

RESUMO

BACKGROUND: Reliable age determination of first-trimester human embryos and fetuses is an important parameter for clinical use and basic science. Age determination by ultrasound or morphometric parameters of embryos 4-6 weeks post conception (p.c.) have been questioned, and more accurate methods are required. Data on whether and how maternal smoking and alcohol consumption influence embryonic and fetal foot growth is also lacking. METHODS: Embryonic tissue from 102 first-trimester legal abortions (aged 35-69 days p.c.) were collected. All women answered a questionnaire concerning smoking and drinking habits, and delivered a urine sample for cotinine analysis. Embryonic age was evaluated by vaginal ultrasound measurements and by post-termination foot length and compared with the Carnegie stages. RESULTS: Foot bud and foot plate were defined and measured as foot length in embryos aged 35-47 days p.c. (range 0.8-2.1 mm). In embryos and fetuses aged 41-69 days p.c., heel-toe length was measured (range 2.5-7.5 mm). We found a significant linear correlation between foot length and age. Morphology of the feet was compared visually with the Carnegie collection, and we found that the mean ages of the two collections correlated well. Foot length was independent of gender, Environmental Tobacco Smoke, maternal smoking and alcohol consumption. CONCLUSION: Foot length correlated linearly to embryonic and foetal age, and was unaffected by gender, ETS, maternal smoking and alcohol consumption.


Assuntos
Pé/embriologia , Idade Gestacional , Fumar/efeitos adversos , Cotinina/urina , Feminino , Humanos , Exposição Materna , Gravidez , Primeiro Trimestre da Gravidez , Análise de Regressão , Ultrassonografia Pré-Natal
7.
Hum Reprod ; 24(10): 2558-66, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19553240

RESUMO

BACKGROUND: Prenatal exposure to maternal cigarette smoking or compounds of cigarette smoke is associated with serious reproductive hazards such as apoptotic death of oogonia in murine offspring and decreased fecundability in human offspring. The present study addresses potential effects of in utero exposure to cigarette smoking. METHODS: Twenty-nine human first-trimester ovaries from legal abortions [aged 38-64 days post-conception (p.c.)] were collected. Mothers filled out a questionnaire about their smoking habits and delivered a urine sample for cotinine analysis. The ovarian cell numbers were estimated using stereological methods. RESULTS: A non-linear correlation between the numbers of oogonia and somatic cells in relation to age of the embryo/fetus was shown in 28 ovaries, including the first estimates performed in ovaries younger than 47 days p.c. Prenatal exposure to smoke showed a significant decrease in the number of somatic cells (P < or = 0.01). The number of oogonia was not significantly associated with prenatal exposure to maternal smoking (P < or = 0.09). The ratio between the two cell types decreased considerably from 1:45 to 1:23 from 38 to 46 days p.c. and was not affected by smoking. CONCLUSIONS: Oogonia proliferate and/or invade the developing ovary at a much faster relative rate than somatic cells. In utero exposure to maternal smoking significantly reduces the number of somatic cells from Days 38 to 64 p.c. Since oocytes cannot survive without being enclosed by somatic cells in a follicle, reduction in the somatic cells number may have long-range consequences on the number of oocytes available in adult life and on the future fertility of female offspring exposed to smoking in utero.


Assuntos
Embrião de Mamíferos/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Feto/efeitos dos fármacos , Exposição Materna , Oogônios/efeitos dos fármacos , Fumar , Adolescente , Adulto , Proliferação de Células/efeitos dos fármacos , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Feminino , Feto/citologia , Humanos , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/embriologia , Ovário/citologia , Ovário/efeitos dos fármacos , Ovário/embriologia , Gravidez , Primeiro Trimestre da Gravidez
8.
Science ; 212(4496): 817-8, 1981 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-7221564

RESUMO

Gonads were removed from fetal mice at about the time that gonadal sex differentiation occurs. The gonads were cultured in vitro with or without their mesonephric tissue. When gonads and ducts removed from sexually undifferentiated fetuses were cultured together, the gonads of both sexes developed female characteristics, whereas gonads cultured without mesonephros developed according to the sex of the fetus from which they were removed. Gonads of sexually differentiated fetuses developed whether they were cultured with or without the mesonephros.


Assuntos
Mesonefro/fisiologia , Ovário/embriologia , Testículo/embriologia , Animais , Técnicas de Cultura , Indução Embrionária , Feminino , Idade Gestacional , Masculino , Camundongos , Ductos Paramesonéfricos/fisiologia , Diferenciação Sexual , Ductos Mesonéfricos/fisiologia
9.
Hum Reprod ; 23(1): 37-45, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17932084

RESUMO

BACKGROUND: Oocyte competence for maturation and embryogenesis is associated with diameter in many mammals. We aimed to test whether this relationship exists in humans and to quantify its impact upon in vitro maturation (IVM). METHODS: We used computer-assisted image analysis daily to measure average diameter, zona thickness and other parameters in oocytes. Immature oocytes originated from unstimulated patients with polycystic ovaries, and from stimulated patients undergoing intracytoplasmic sperm injection (ICSI). Some were cultured with meiosis activating sterol (FF-MAS). Matured oocytes were inseminated using ICSI and embryo development was monitored. In vivo matured oocytes were also measured. RESULTS: Immature oocytes were smaller at collection than in vivo matured oocytes. Maturation was related to oocyte diameter and many oocytes grew in culture. FF-MAS stimulated growth in oocytes derived from ICSI patients, but only stimulated growth in PCO derived oocytes if they matured in vitro. Degenerating oocytes showed cytoplasmic shrinkage. Neither zona thickness, perivitelline space, nor the total diameter of the oocyte plus zona were informative regarding maturation capacity. CONCLUSIONS: Immature oocytes grow during maturation culture. FF-MAS promotes oocyte growth in vitro. Oocytes from different sources have different growth profiles in vitro. Measuring oocytes in clinical IVM may provide additional non-invasive information that could potentially avoid the use of growing oocytes.


Assuntos
Oócitos/crescimento & desenvolvimento , Síndrome do Ovário Policístico/patologia , Injeções de Esperma Intracitoplásmicas , Adulto , Tamanho Celular , Células Cultivadas , Colestenos/farmacologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Oócitos/citologia , Oócitos/patologia , Oócitos/fisiologia
10.
Mol Cell Endocrinol ; 234(1-2): 87-93, 2005 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-15836957

RESUMO

Survival and growth of follicles in human ovarian tissue is presently only performed with limited success. We evaluated the effect of anti-Müllerian hormone (AMH) and/or testosterone on follicular growth during a 4-week culture period using ovarian cortical tissue from six women in their reproductive years. The cortex of each biopsy was isolated and immediately cryopreserved upon collection and stored in liquid nitrogen. After thawing the tissue was placed in culture. After the culture period all follicles were counted on histological sections and classified for viability and stage of development. Based on evaluation of 6603 follicles it was found that the number of growing follicles significantly increased during the culture period as compared to the uncultured control, irrespective of the composition of the culture medium. Furthermore, significantly more follicles advanced to the primary and secondary stage (p<0.05) in tissue cultured with AMH (54%) as compared to tissue cultured in control medium (41%). The mean diameter of follicles classified as primary follicles was significantly enhanced in tissue cultured in the presence of AMH (p=0.002) and AMH plus testosterone (p<0.001) as compared to that observed in tissue cultured with control medium and medium containing testosterone alone. In contrast the mean diameter of the oocyte and its nucleus remained similar irrespective of culture medium. In conclusion, AMH seems to affect early stages of human follicular development by enhancing recruitment, survival and/or growth during a 4-week culture period.


Assuntos
Glicoproteínas/farmacologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Hormônios Testiculares/farmacologia , Adulto , Hormônio Antimülleriano , Núcleo Celular/efeitos dos fármacos , Feminino , Glicoproteínas/fisiologia , Humanos , Folículo Ovariano/citologia , Hormônios Testiculares/fisiologia , Testosterona/farmacologia , Testosterona/fisiologia
11.
J Mol Med (Berl) ; 76(12): 818-23, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9846952

RESUMO

Several years ago we discovered that spent media from cultured human and bull testes contain components that initiate meiosis in germ cells from fetal mouse testes which have been cultured for 6 days in the spent medium. The active substance(s) was termed meiosis-inducing substance. We later found that human follicular fluid harvested after stimulation with gonadotropins has a similar effect. These meiosis-activating substances have now been identified and characterized in extracts from bull testes and human preovulatory follicular fluid as naturally occurring sterols (meiosis-activating sterols, MAS). MAS are intermediates in the cholesterol biosynthetic pathway and are thus present in all cells which produce cholesterol de novo and from lanosterol. However, MAS accumulate only in the gonads. We discuss the possible physiological role of these sterols in initiating meiosis and in oocyte resumption of meiosis, and their potential use in promoting and preventing fertility.


Assuntos
Meiose/fisiologia , Esteróis , Animais , Bioensaio , Feminino , Fertilidade , Humanos , Masculino , Mitose , Óvulo , Espermatozoides , Esteróis/isolamento & purificação , Esteróis/farmacologia
12.
J Clin Endocrinol Metab ; 55(4): 693-8, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7107813

RESUMO

Granulosa cell aspirates from human ovarian follicles were analyzed by flow cytometry to determine the fraction of cells in the DNA S-phase of the mitotic cell cycle. The aim of the study was to evaluate if the percentage of granulosa cells in S-phase (the S-fraction) could be used to indicate whether a follicle was healthy or atretic. A highly significant relationship was found between the S-fraction and the concentration of estradiol in the follicular fluid (r = 0.6, P less than 0.001). More than 85% of the follicles having an S-fraction of 16% or greater contained intrafollicular levels of estradiol equal to or greater than 200 ng/ml and had a low androstenedione:estradiol ratio. Conversely, 95% or more of the follicles that had an S-fraction of less than 16% contained low estradiol (less than 200 ng/ml) and had a high androstenedione to estradiol ratio. We conclude that flow cytometric DNA measurements on follicular aspirates provide a reliable and rapid method by which to distinguish healthy and atretic ovarian follicles. Since only a small fraction (less than 5%) of an entire granulosa cell population is required for S-phase analysis, the technique allows the majority of cells to be immediately available or other biochemical studies. Moreover, since excision of ovarian tissue is avoided, the technique may be acceptable for studies on women with normal ovarian function but who are undergoing laparotomy or laparoscopy for some reason.


Assuntos
DNA/análise , Células da Granulosa/citologia , Folículo Ovariano/anatomia & histologia , Adolescente , Adulto , Androstenodiona/análise , Líquidos Corporais/análise , Estradiol/análise , Feminino , Citometria de Fluxo , Células da Granulosa/análise , Humanos , Mitose , Folículo Ovariano/análise
13.
J Endocrinol ; 127(2): 363-7, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2250159

RESUMO

Levels of epidermal growth factor (EGF) and steroids were measured by radioimmunoassay in follicular fluid (FF) aspirated from 114 small antral follicles with diameters from 1 to 6 mm and in serum from 19 women undergoing Caesarean section at term. Concentrations of EGF in FF were inversely and significantly correlated to follicular size, being 4.7 +/- 0.4 (mean +/- S.E.M.) nmol/l in follicles of 1-2 mm in diameter and declining to 2.2 +/- 0.2 and 1.4 +/- 0.2 nmol/l in follicles of 3-4 mm and 5-6 mm in diameter respectively. The mean +/- S.E.M. concentration of EGF in serum (0.7 +/- 0.03 nmol/l) was significantly lower than that in FF. Levels of EGF, progesterone and oestradiol in FF were not significantly correlated to one another. In contrast to EGF, levels of progesterone and oestradiol in FF did not vary significantly with follicular diameter in these small follicles. On the basis of these results we suggest that EGF is synthesized in small human antral follicles, and that EGF stimulates granulosa cell proliferation and follicle growth up to 6 mm in diameter. Furthermore, the high intrafollicular levels of EGF may protect the small follicles against untimely effects of high levels of FSH, for instance during the mid-cycle surge of gonadotrophins. It is concluded that EGF plays an important role as an autocrine and/or paracrine regulator of development of small antral follicles in women.


Assuntos
Fator de Crescimento Epidérmico/análise , Líquido Folicular/química , Gravidez/metabolismo , Adolescente , Adulto , Fator de Crescimento Epidérmico/sangue , Estradiol/análise , Feminino , Humanos , Folículo Ovariano/anatomia & histologia , Progesterona/análise , Radioimunoensaio
14.
J Endocrinol ; 167(1): 29-37, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11018750

RESUMO

This study examined whether the endocrine disruptor octylphenol (OP) mimics the synthetic oestrogen diethylstilbestrol (DES) in ability to induce oestrogen receptor-alpha (ER-alpha) expression in the newborn mouse uterine epithelium after prenatal exposure. Pregnant mice were given daily s.c. injections with DES (10 or 100 microgram DES/kg maternal wt) or OP (100 or 250 mg/kg maternal wt) or with vehicle alone from day 11.5 to 16.5 of pregnancy. ER-alpha expression was evaluated on histological sections by detecting ER-alpha mRNA with the in situ hybridization technique and ER-alpha protein using immunohistochemistry. The immunostaining was quantitated using a microspectrophotometer. Oestrogen-like activity of the DES and OP batches used for in vivo exposure was confirmed in an in vitro assay based on transient gene expression of an oestrogen-dependent reporter plasmid. In mice exposed prenatally to vehicle alone, the uterine epithelium did not express either ER-alpha mRNA or protein, while both were highly expressed in the stroma. Exposure to either DES dose induced the expression of both ER-alpha mRNA and protein in the epithelium, whereas it was unchanged in the stroma. In contrast, neither OP dose induced the expression of ER-alpha mRNA or protein in the epithelium and expression was unchanged in the stroma. Our data stress the importance of in vivo studies when investigating endocrine disruptors.


Assuntos
Dietilestilbestrol/farmacologia , Fenóis/farmacologia , Efeitos Tardios da Exposição Pré-Natal , Receptores de Estrogênio/efeitos dos fármacos , Útero/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Epitélio/metabolismo , Receptor alfa de Estrogênio , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas Imunoenzimáticas , Hibridização In Situ , Camundongos , Gravidez , RNA Mensageiro/genética , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Tensoativos/farmacologia , Útero/metabolismo
15.
Mol Cell Endocrinol ; 164(1-2): 191-6, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11026570

RESUMO

Meiosis-activating sterol (MAS) has been shown to induce mouse oocytes cultured in the presence of hypoxanthine (HX) to resume meiosis. The present research was conducted to determine whether amphotericin B or ketoconazole (a promoter and an inhibitor of production of MAS), affected oocyte maturation. Mouse cumulus cell-enclosed oocytes (CEO) or denuded oocytes (DO) were cultured for 24 h in the presence of 4 mM HX with FSH or amphotericin B or ketoconazole. At the end of the culture, the frequency of germinal vesicle break down (GVBD) and polar body formation (PB) were recorded. The results demonstrated: (i) FSH (10-200 IU/l) induced dose-dependent oocytes maturation in CEO, but was without effect on DO. A maximum increase in GVBD and PB was observed with 25-50 IU/l FSH. The presence of FSH (50 IU/l) for 1 h was sufficient to induce meiotic resumption, which after 2 h reached a plateau similar to that of a continuous presence of FSH. (ii) CEO exposed to amphotericin B (0.0025-2.5 microg/l) underwent GVBD dose-dependently, whereas no effect was observed on DO. The presence of amphotericin B (0.025 microg/l) for 1 h stimulated oocyte resumption in a way similar to that of FSH. (iii) Amphotericin B (0.025 microg/l) and FSH (50 IU/l) did not show any additive effect on resumption of meiosis. (iv) Ketoconazole (10(-7)-10(-3) M) inhibited the effect of FSH on resumption of meiosis, but had no effect on oocyte spontaneous maturation. These results show that FSH and amphotericin B induce resumption of meiosis and indicate that they are likely to cause an accumulation of meiosis activating sterols in the CEO, but ketoconazole blocks the production of MAS. The present study supports the notion that MAS plays a physiological relevant role in triggering resumption of meiosis in mouse oocytes.


Assuntos
Anfotericina B/farmacologia , Antibacterianos/farmacologia , Cetoconazol/farmacologia , Oócitos/citologia , Oócitos/efeitos dos fármacos , Esteróis/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Meiose/efeitos dos fármacos , Camundongos , Oócitos/metabolismo
16.
Mol Cell Endocrinol ; 184(1-2): 25-32, 2001 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-11694338

RESUMO

Previously, we identified a partial cDNA sequence of a novel human transcript, designated fetal and adult testis expressed transcript (FATE). FATE is testis-specific in fetal life and co-expressed with SRY in a 7 weeks old fetal testis, suggesting a function in early testicular differentiation. Herein, full-length cDNA clones of human and porcine FATE were isolated and the gene structure and promoter region of the human FATE gene was characterized. The human FATE gene, which maps to Xq28, consists of five exons spanning approximately 7 kb of genomic DNA. Examination of 1 kb of the FATE promoter region revealed the presence of a putative steroidogenic factor 1 (SF-1) binding site at position -79 to -71 upstream of the transcription start site. We propose that FATE might represent a novel target gene of SF-1 in human testicular differentiation and/or germ cell development.


Assuntos
DNA Complementar/genética , Proteínas de Ligação a DNA/genética , Testículo/metabolismo , Fatores de Transcrição/genética , Cromossomo X/genética , Adulto , Animais , Sequência de Bases , Sítios de Ligação , Mapeamento Cromossômico , DNA Complementar/isolamento & purificação , Proteínas de Ligação a DNA/isolamento & purificação , Feto , Fatores de Transcrição Fushi Tarazu , Genes sry , Ligação Genética , Proteínas de Homeodomínio , Humanos , Masculino , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Receptores Citoplasmáticos e Nucleares , Fator Esteroidogênico 1 , Suínos , Fatores de Transcrição/isolamento & purificação
17.
APMIS ; 107(7): 631-5, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10440058

RESUMO

MIC2 is a pseudoautosomal gene localized on X and Y chromosomes. The MIC2 gene product is a glycoprotein expressed on the cell membranes of a number of somatic cells, including Sertoli cells of the testis, but not on the cell membranes of germ cells. In cases of cryptorchidism, a testicular biopsy is recommended in order to evaluate future fertility potential. The spermatogonia are identified on histological sections and the number per tubular transverse section is compared with normal values for age. The patient is at 33-100% risk of subsequent infertility when the number of spermatogonia per tubular transverse section is lower than 1% of the lowest normal age-matched value. Besides Sertoli cells the seminiferous tubules in undescended testes contain only a few germ cells, and it may be difficult to pinpoint the germ cells in small biopsies. Especially in nonpalpable testes their number may be heavily reduced. A reliable identification of germ cells may also be difficult in cultures of testicular biopsies from undescended testes. Against this background, we tried the use of an immunohistochemical method with DAKO antibody to the MIC2 gene product (MIC2, 12 E7, code no. M3601) in order to obtain a "negative reaction" of germ cells, contrasting with the stained Sertoli cells. The material comprised: 44 specimens of testicular parenchyma taken at time of surgery for cryptorchidism from 24 cryptorchid boys with nonpalpable testes and 14 testicular biopsies from 13 cryptorchid patients with palpable testes which had been cultured in vitro for 7, 14 or 21 days. In all cases the immunohistochemical method with DAKO antibody to the MIC2 gene product was helpful for identification of Sertoli cells and germ cells, and we therefore recommend the use of anti-MIC2 in all testicular biopsies where it is difficult to pinpoint the germ cells.


Assuntos
Antígenos CD , Moléculas de Adesão Celular , Criptorquidismo , Proteínas/análise , Células de Sertoli/química , Espermatozoides/química , Testículo/química , Antígeno 12E7 , Adolescente , Criança , Criptorquidismo/patologia , Humanos , Lactente , Masculino , Testículo/citologia , Testículo/patologia
18.
Fertil Steril ; 35(2): 199-204, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7202743

RESUMO

The initiation of meiosis is controlled by two substances, a meiosis-inducing substance (MIS) and a meiosis-preventing substance (MPS). These have been shown to be present in reproductive organs of both sexes of different mammals. In this investigation MIS and MPS were also shown to be present in man. MIS was found in fetal and adult epididymides and testes. MPS was obtained from the tests of one fetus, which was delivered by laparotomy. MPS could not be found in the testes of another fetus, which was aborted by prostaglandin F2 alpha and oxytocin. No or only weak MPS activity was detectable in the adult testis. This report indicates that continued spermatogenesis might be influenced by the MIS:MPS ratio. MPS was shown not to be species-specific. MIS and MPS activity have been evaluated by qualitative scoring of the different germ cell stages present in fetal gonads after culture in used media containing MIS or MPS.


Assuntos
Epididimo/citologia , Testículo/citologia , Adulto , Animais , Meios de Cultura , Feminino , Feto/citologia , Células Germinativas/citologia , Humanos , Masculino , Meiose , Camundongos
19.
Fertil Steril ; 73(4): 742-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10731535

RESUMO

OBJECTIVE: To compare IVF and pregnancy outcomes before and after anovulation induced by oral contraceptives. DESIGN: Observational clinical study. SETTING: Infertility clinic. PATIENT(S): Forty women with two intact ovaries (32 of 40 couples with male factor infertility and 8 with unknown causes of infertility) underwent 190 IVF treatment cycles (55 natural cycles and 135 clomiphene citrate-stimulated cycles). INTERVENTION(S): If the women failed to conceive after 2-4 IVF treatment cycles, oral contraceptives were used to induce anovulation for 1 month before IVF was performed in two consecutive cycles. MAIN OUTCOME MEASURE(S): Rates of oocyte retrieval, fertilization, cleavage, preembryo formation, pregnancy, and implantation were compared before and after a period of anovulation. RESULT(S): The pregnancy rate per cycle of the first and second cycle combined (23%) and that of the second cycle alone (30%) after a period of anovulation were significantly higher than that observed before a period of anovulation (9%). CONCLUSION(S): Anovulation induced by oral contraceptives, showing bilateral ovarian quiescence, enhances pregnancy rates in the following two menstrual cycles of IVF treatment.


PIP: This observational clinical study compared the in vitro fertilization (IVF) and pregnancy outcomes before and after anovulation induced by oral contraceptives. A total of 40 patients from the Fukuda Ladies Clinic, Japan, with two intact ovaries who underwent 190 IVF treatment cycles were enrolled in the study. If the women failed to conceive after 2-4 IVF treatment cycles, oral contraceptives were used to induce anovulation for 1 month before IVF was performed in two consecutive cycles. Rates of oocyte retrieval, fertilization, cleavage, pre-embryo formation, pregnancy, and implantation were compared before and after a period of anovulation. Results revealed that the pregnancy rate per cycle of the first and second cycle combined (23%) and that of the second cycle alone (30%) after a period of anovulation were significantly higher than that observed before a period of anovulation (9%). Based on this finding, it is concluded that anovulation induced by oral contraceptives, showing bilateral ovarian quiescence, enhances pregnancy rates in the following two menstrual cycles of IVF treatment.


Assuntos
Anovulação/induzido quimicamente , Anticoncepcionais Orais Sintéticos/uso terapêutico , Fertilização in vitro/métodos , Adulto , Clomifeno/uso terapêutico , Implantação do Embrião , Embrião de Mamíferos/fisiologia , Etinilestradiol/uso terapêutico , Estudos de Avaliação como Assunto , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Humanos , Ciclo Menstrual , Norgestrel/uso terapêutico , Indução da Ovulação , Gravidez , Taxa de Gravidez
20.
Fertil Steril ; 40(1): 73-9, 1983 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6683202

RESUMO

Ovarian antral follicles from patients with breast cancer were compared with follicles from healthy women. Steroid levels in the follicular fluid and the health status of the follicles were evaluated. Follicles were judged to be healthy or atretic by flow cytometric determinations of the deoxyribonucleic acid content of aspirated granulosa cell nuclei. Fifteen of the 25 follicles (60%) from the cancer patients contained unmeasurable or abnormally low steriod levels (i.e., less than 100 ng/ml) which were significantly (P less than 0.001) lower than in follicles of the same health status from healthy women (500 to 1000 ng/ml). It is speculated whether substances other than the usual follicular steriods are produced by the cancer patients, which stimulate mitotic activity of the granulosa cells.


Assuntos
Neoplasias da Mama/fisiopatologia , Folículo Ovariano/fisiopatologia , Adulto , Neoplasias da Mama/metabolismo , Estradiol/análise , Feminino , Citometria de Fluxo , Crescimento , Humanos , Masculino , Pessoa de Meia-Idade , Folículo Ovariano/anatomia & histologia , Ovário/anatomia & histologia , Progesterona/análise , Testosterona/análise
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