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1.
Reprod Biol Endocrinol ; 19(1): 182, 2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34886872

RESUMEN

OBJECTIVE: Luteinizing hormone (LH) and human chorionic gonadotropin (hCG) activate distinct intracellular signaling cascades. However, due to their similar structure and common receptor, they are used interchangeably during ovarian stimulation (OS). This study aims to assess if the source of LH used during OS affects IVF outcome. PATIENTS AND METHODS: This was a cross sectional study of patients who underwent two consecutive IVF cycles, one included recombinant follicular stimulating hormone (FSH) plus recombinant LH [rFSH+rLH, (Pergoveris)] and the other included urinary hCG [highly purified hMG (HP-hMG), (Menopur)]. The OS protocol, except of the LH preparation, was identical in the two IVF cycles. RESULTS: The rate of mature oocytes was not different between the treatment cycles (0.9 in the rFSH+rLH vs 0.8 in the HP-hMG, p = 0.07). Nonetheless, the mean number of mature oocytes retrieved in the rFSH+rLH treatment cycles was higher compared to the HP-hMG treatment cycles (10 ± 5.8 vs 8.3 ± 4.6, respectively, P = 0.01). Likewise, the mean number of fertilized oocytes was higher in the rFSH+rLH cycles compared with the HP-hMG cycles (8.5 ± 5.9 vs 6.4 ± 3.6, respectively, p = 0.05). There was no difference between the treatment cycles regarding the number of top-quality embryos, the ratio of top-quality embryos per number of oocytes retrieved or fertilized oocytes or the pregnancy rate. CONCLUSION: The differences in treatment outcome, derived by different LH preparations reflect the distinct physiological role of these molecules. Our findings may assist in tailoring a specific gonadotropin regimen when assembling an OS protocol.


Asunto(s)
Fertilización In Vitro/métodos , Hormona Folículo Estimulante/administración & dosificación , Hormona Luteinizante/administración & dosificación , Menotropinas/administración & dosificación , Inducción de la Ovulación/métodos , Proteínas Recombinantes/administración & dosificación , Adulto , Estudios Transversales , Femenino , Humanos , Embarazo , Índice de Embarazo , Resultado del Tratamiento
2.
Angew Chem Int Ed Engl ; 60(28): 15517-15523, 2021 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-33939866

RESUMEN

Phenyltelluroxane clusters of the composition [{(PhTe)19 O24 }2 I18 (solv)] (1) are formed during the hydrolysis of [PhTeI3 ]2 or the oxidation of various phenyltellurium(II) compounds with iodine under hydrolytic conditions. The compounds consist of two half-spheres with a {(PhTe)19 O24 }9+ network, which are connected by 18 iodine atoms. The spherical clusters can accommodate solvent molecules such as pyridine or methanol in the center of two rings formed by iodine atoms. The presence of other metal ions during the cluster formation results in a selective replacement of the central {PhTe}3+ units of each half-sphere as has been demonstrated with the isolation of [{(PhTe)18 ({Ca(H2 O)2 }O24 }2 I16 ] (2) and [{(PhTe)18 ({Y(NO3 )(H2 O)}O24 }2 I16 ] (3). A crownether-like coordination by six oxygen atoms of the telluroxane network is found for the {Ca(H2 O}2 }2+ and {Y(NO3 )(H2 O)}2+ building blocks. Mass spectrometric studies show that considerable amounts of the intact clusters are transferred to the gas phase without dissociation.

3.
Clin Exp Obstet Gynecol ; 37(2): 100-4, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21077495

RESUMEN

AIMS: To determine serum retinol-binding rotein 4 (RBP-4) levels in polycystic ovary syndrome (PCOS) patients undergoing controlled ovarian hyperstimulation (COH) for an in vitro fertilization-embryo transfer (IVF-ET) cycle and the possible correlation to COH variables. PATIENTS AND METHODS: 11 consecutive PCOS patients undergoing our routine IVF flexible multidose gonadotropin-releasing hormone (GnRH)-antagonist protocol. Blood was drawn three times during the COH cycle: (1) day 1 or 2 of menstruation, and prior to gonadotropin administration (Day-S) (Day-S); (2) day of or prior to human chorionic gonadotropin (hCG) administration (Day-hCG); and (3) day of ovum pick-up (Day-OPU). Levels of estradiol and serum RBP-4 were compared among the three time points. Serum RBP-4 was measured with a commercial immunoassay. RESULTS: Results showed significantly lower levels of serum RBP-4 on Day-OPU and Day-hCG than on Day-S. Though significant correlations were observed between serum RBP-4 and body mass index, fasting glucose or glucose to insulin ratio, no correlations were found between serum RBP-4 and IVF treatment variables or pregnancy rate. CONCLUSION: While serum RBP-4 decreases during COH for IVF, there is apparently no correlation of serum RBP-4 levels with IVF treatment variables or outcome.


Asunto(s)
Inducción de la Ovulación , Síndrome del Ovario Poliquístico/sangre , Proteínas Plasmáticas de Unión al Retinol/metabolismo , Adulto , Estradiol/sangre , Femenino , Fertilización In Vitro , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Humanos , Estudios Longitudinales , Estudios Prospectivos , Adulto Joven
4.
Clin Exp Obstet Gynecol ; 31(2): 123-6, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15266766

RESUMEN

OBJECTIVE: In a previous study treatment with a daily standard dose of Femarelle (644 mg/day) resulted in a significant elevation in bone mineral density (BMD) while a reduced dose resulted in a decrease in BMD. The aim of the current study was to examine the efficacy and safety of the two doses of Femarelle in the treatment of menopausal symptoms. MATERIALS AND METHODS: Eighty healthy postmenopausal women were randomly allocated to receive either the standard dose (SD) or low dose (LD) of Femarelle (644 mg/day vs 344 mg/day). A detailed medical history was taken on enrollment, followed by a physical examination, pelvic ultrasound, and sex hormone and lipid profiles. A detailed Kupperman index for each patient was completed. These measures were repeated every three months for 12 months. RESULTS: In both groups there was a significant reduction in the Kupperman index following 12 weeks of treatment, which was sustained throughout the 12 months of treatment (p < 0.01). Seventy-six percent of the patients in the SD group reported a decrease in vasomotor symptoms and seventy eight % in the LD group (NS). This decrease was sustained following 12 months of treatment. There was no change in TSH and sex hormone levels or endometrial thickness during the study period. CONCLUSIONS: In the current study we found that menopausal symptoms were reduced similarly by LD and SD, however for the combined treatment of menopausal symptoms and osteoporosis the standard dosage of 644 mg/day of Femarelle is needed.


Asunto(s)
Glycine max , Sofocos/tratamiento farmacológico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Densidad Ósea , Esquema de Medicación , Femenino , Sofocos/patología , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/patología , Extractos Vegetales/administración & dosificación , Resultado del Tratamiento
5.
Hum Reprod ; 19(3): 715-22, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14998975

RESUMEN

BACKGROUND: Placenta immunomodulatory ferritin (PLIF) cDNA was recently cloned from the human placenta, where it is expressed in syncytiotrophoblast and decidual mononuclear cells. PLIF and its subcloned bioactive domain (C48), expressed in Escherichia coli, are immunosuppressive proteins and induce pronounced IL-10 production in vitro and in vivo. METHODS AND RESULTS: PLIF serum level, measured by enzyme-linked immunosorbent assay, was elevated in pregnant mice throughout gestation and declined towards delivery. Blocking of PLIF activity by vaccination of mice with C48 prior to mating inhibited pregnancy development. Passive transfer of anti-C48 immunoglobulin (Ig) starting at 3.5-12.5 days post coitum (dpc) resulted in high rate of embryo resorption. Furthermore, treatment with anti-C48 Ig resulted in placental and embryonal growth restriction. At gestation day 13.5, growth retardation was especially notable in the placentae, while at 16.5 dpc it was pronounced in the embryos. Histopathological examination revealed that experimental placentae were globally hypoplastic and the labyrinth was strikingly pale and contained less maternal blood compared with control. Immune-activated spleen cells harvested at 13.5 dpc from anti-C48 Ig-treated pregnant mice secreted in vitro increased level of Th1 cytokines (IL-2, TNF-alpha, IL-12) and decreased level of Th2 cytokines (IL-10, IL-4, IL-5, IL-6) as compared with the level of the respective cytokines secreted by spleen cells from control pregnant mice. CONCLUSION: This study provides the first in vivo evidence that PLIF plays a major role in placentation and embryonic growth.


Asunto(s)
Citocinas/metabolismo , Desarrollo Embrionario y Fetal/fisiología , Ferritinas/fisiología , Placentación , Proteínas Gestacionales/fisiología , Preñez/fisiología , Células TH1/metabolismo , Animales , Animales Recién Nacidos/anatomía & histología , Peso Corporal/fisiología , Células Cultivadas , Concanavalina A/farmacología , Anticoncepción Inmunológica , Copulación , Parto Obstétrico , Pérdida del Embrión/inmunología , Desarrollo Embrionario y Fetal/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Femenino , Ferritinas/química , Ferritinas/inmunología , Ferritinas/farmacología , Feto/patología , Inmunización Pasiva , Inmunoglobulinas/inmunología , Inmunoglobulinas/farmacología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos ICR , Placenta/efectos de los fármacos , Placenta/patología , Embarazo , Resultado del Embarazo , Proteínas Gestacionales/química , Proteínas Gestacionales/inmunología , Proteínas Gestacionales/farmacología , Preñez/sangre , Estructura Terciaria de Proteína/fisiología , Bazo/citología , Bazo/efectos de los fármacos , Bazo/metabolismo , Células Th2/metabolismo , Vacunación
6.
J Obstet Gynaecol ; 24(8): 911-3, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16147650

RESUMEN

In order to optimise the service for patients who require an emergency service, and to meet patient needs, we conducted a study in Shillo ambulatory outpatient women's health centre, affiliated to Rabin Medical Center and Tel Aviv University. The study population consisted of 512 women, aged 25 - 55 years, attending the centre for emergency consultation and urgent obstetrics and gynaecological day care. Before the doctor's visit and at the end of the session, the women were asked to complete a 20-item questionnaire survey. The most common complaints were related to pregnancy complications (29%). Significant improvement in their problems was reported by almost 70% of these women; 20% thought that the information they received was inadequate or unsatisfactory. Less than 10% were referred to the hospital for further care such as surgery. Most of the women (96%) reported that they would continue to use these emergency services in the future if needed. There was a statistically significant difference between the doctors' opinion and the nurse regarding the urgency and severity of the patients' problems. The nurses graded them lower than did the doctors. There was also a statistically significant difference between patients' opinion and the nurses and the doctors regarding the urgency and severity of the patients' problems. The patients graded the problems as more urgent and more severe than the nurses or doctors. We concluded that an ambulatory emergency service is an essential part of an ideal ambulatory womens' health centre but it requires substantial progress to meet the patients' needs.


Asunto(s)
Atención Ambulatoria/estadística & datos numéricos , Servicios Médicos de Urgencia/estadística & datos numéricos , Salud de la Mujer , Adulto , Actitud del Personal de Salud , Femenino , Enfermedades de los Genitales Femeninos/terapia , Humanos , Persona de Mediana Edad , Satisfacción del Paciente , Embarazo , Complicaciones del Embarazo/terapia , Encuestas y Cuestionarios
7.
Gynecol Endocrinol ; 17(3): 255-9, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12857434

RESUMEN

The aim of this study was to assess the knowledge, perception, and attitude towards personal health care and menopause among women with ischemic heart disease. The study population consisted of 100 menopausal women attending the cardiac unit for coronary angiography. All women completed a 20-item questionnaire, covering information on health-care habits, life style and attitude towards menopause. About half of the study population had ever smoked, were overweight, had never tried to lose weight and did not exercise regularly. The majority regularly underwent screening mammography, Pap smear and lipid profile measurement. There was a positive statistically significant correlation between years of education and having annual mammography, Pap smear and lipid profile, performing breast self-examinations and taking an annual vacation. Sixty eight per cent of the study population had never used hormone replacement therapy (HRT), 13.2% had used HRT in the past and 18.8% were currently using HRT. There was a negative statistically significant correlation between use of HRT and age and number of children, and a positive statistically significant correlation between use of HRT and having an annual Pap smear and mammography scan. Only a relatively small percentage of the study population safeguarded their health care or used HRT. We believe that stronger efforts are needed to promote good health-related behaviors for these women.


Asunto(s)
Angiografía Coronaria , Conocimientos, Actitudes y Práctica en Salud , Menopausia , Isquemia Miocárdica/diagnóstico por imagen , Anciano , Actitud Frente a la Salud , Escolaridad , Terapia de Reemplazo de Estrógeno , Femenino , Estado de Salud , Humanos , Estilo de Vida , Lípidos/sangre , Mamografía , Persona de Mediana Edad , Prueba de Papanicolaou , Frotis Vaginal
8.
Maturitas ; 43(2): 113-6, 2002 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-12385859

RESUMEN

OBJECTIVE: To assess Israeli women gynecologists toward their own health, their health related behaviors and to assess attitude towards and the use of hormone replacement therapy (HRT). METHODS: Ninety five actively employed hospital and community women gynecologist completed a questionnaire on attitude towards self-health, way of life, smoking habits, and regular breast, blood, pap smear examinations and HRT. RESULTS: Mean BMI was 25.3 Kg/m(2)+/-4.2, 61% considered themselves above average weight, and only 39% estimated their weight as appropriate. Fifty six percent were on active weight-loss diets, and 35% were current smokers. Blood tests, pap smears and breast evaluations were regularly done by 73.4, 91.5, and 64.1%, respectively. Overall, 74% of the gynecologists had a positive opinion about HRT; 70% of the menopausal subgroup had ever used HRT, and 93.3% of the perimenopausal subgroup intended to use it. The main reason for starting HRT was climacteric symptoms, and for stopping or avoiding HRT were equally bleeding, fear of cancer and adverse reactions towards HRT. By far the oral HRT mode was the most popular and 90% of users expressed satisfaction with treatment. CONCLUSIONS: Israeli women gynecologists are aware and maintain carefully their health, excluding cigarette smoking. The high rate of use and awareness of HRT among this group is encouraging considering that gynecologist serves as role model for the public and maintains the main source of HRT in the community.


Asunto(s)
Actitud del Personal de Salud , Actitud Frente a la Salud , Médicos Mujeres/psicología , Índice de Masa Corporal , Femenino , Terapia de Reemplazo de Hormonas , Humanos , Israel , Estilo de Vida , Persona de Mediana Edad
9.
Clin Exp Obstet Gynecol ; 29(2): 91-4, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12171325

RESUMEN

PURPOSE: The aim of the study was to assess the knowledge, perception and attitude towards menopause and hormone replacement therapy (HRT) among women of different ethnic groups in Israel. METHODS: 292 postmenopausal women attending primary health-care centers in northern Israel were recruited. All women completed a questionnaire, which included information on demographics, health status, menopausal symptoms, attitude toward menopause, adequacy of counseling and experience with HRT. RESULTS: Thirty-five percent of women were Arabic women. Most of the population categorized menopause as a positive and natural event, only 26% of the Arabic women thought of menopause as an illness-oriented event compared to 7.7% of the Jewish women. Half the Arabic women had never received information or been counseled about menopause and HRT, compared to 18% of the Jewish women. Menopausal symptoms showed a statistically significant improvement with HRT. However, only 40% of the Jewish women and 24% of the Arabic women used HRT. CONCLUSIONS: Only a relatively small percentage of Arabic women know about menopause and HRT use, probably because of the relatively low rate of counseling and information provided about menopause and HRT, and their lack of knowledge. Greater efforts are needed to promote a positive attitude to aging and menopause, increase awareness and knowledge. Providing greater access to information and support are essential steps in improving the women's health of the Arabic population in Israel during menopausal years.


Asunto(s)
Árabes , Actitud/etnología , Terapia de Reemplazo de Estrógeno , Judíos , Menopausia/etnología , Femenino , Humanos , Israel , Persona de Mediana Edad
10.
Gynecol Endocrinol ; 16(5): 349-54, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12587527

RESUMEN

The aim of this study was to assess the health-related behaviors, knowledge and attitude towards menopause and hormone replacement therapy (HRT) among women receiving dialysis treatment. The study population consisted of 44 women aged 55-75 years attending the dialysis unit. All women completed a 20-item questionnaire, which covered information on personal health-care habits, life style and attitude regarding menopause and HRT. The majority of participants were of desirable weight (body mass index < 25 kg/m2) and had a positive body image. About 80% had never smoked, and did not engage in regular physical activity. Over half underwent annual Pap smear, mammography, breast examination by a physician, and only a small minority performed breast self-examination. Surprisingly, 45% had used HRT in the past, but only 5% were current users. Although we expected postmenopausal women with a life-threatening disease to be more aware of personal health care than the general population, only a relatively small percentage of the study population safeguarded their health care, and used HRT. Stronger educational efforts may be needed to promote health-related behaviors and a positive attitude to health care, aging and menopause in this subgroup of patients.


Asunto(s)
Terapia de Reemplazo de Estrógeno , Conocimientos, Actitudes y Práctica en Salud , Promoción de la Salud , Posmenopausia , Diálisis Renal , Anciano , Imagen Corporal , Índice de Masa Corporal , Autoexamen de Mamas/estadística & datos numéricos , Escolaridad , Ejercicio Físico , Femenino , Humanos , Estilo de Vida , Mamografía/estadística & datos numéricos , Persona de Mediana Edad , Prueba de Papanicolaou , Examen Físico/estadística & datos numéricos , Fumar/epidemiología , Encuestas y Cuestionarios , Frotis Vaginal/estadística & datos numéricos
11.
Hum Reprod Update ; 7(6): 603-10, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11727869

RESUMEN

Women with Turner's syndrome should be carefully followed throughout life. Growth hormone therapy should be started at age 2-5 years. Hormone replacement therapy for the development of normal female sexual characteristics should be started at age 12-15 years and continued for the long term to prevent coronary artery disease and osteoporosis. Most women with Turner's syndrome have ovarian dysgenesis; therefore, they are usually infertile, and in very rare cases have spontaneous menses followed by early menopause. Only 2% of the women have natural pregnancies, with high rates of miscarriages, stillbirths and malformed babies. Their pregnancy rate in oocyte donation programmes is 24-47%, but even these pregnancies have a high rate of miscarriage, probably due to uterine factors. A possible future prospect is cryopreservation of ovarian tissue containing immature follicles before the onset of early menopause, but methods of replantation and in-vitro maturation still need to be developed. Should these autologous oocytes indeed be used in the future, affected women would need to undergo genetic counselling before conception, followed by prenatal assessment.


Asunto(s)
Infertilidad Femenina/etiología , Ovario/fisiopatología , Síndrome de Turner/fisiopatología , Adolescente , Adulto , Niño , Preescolar , Femenino , Asesoramiento Genético , Terapia de Reemplazo de Hormonas , Hormona de Crecimiento Humana/administración & dosificación , Hormona de Crecimiento Humana/farmacología , Humanos , Infertilidad Femenina/genética , Infertilidad Femenina/fisiopatología , Donación de Oocito , Embarazo , Síndrome de Turner/genética
13.
J Assist Reprod Genet ; 18(3): 151-5, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11411430

RESUMEN

PURPOSE: The purpose of this study is to determine if baseline antral follicle assessment may serve as additional information in predicting in vitro fertilization outcome. METHODS: Prospective, descriptive preliminary study of in vitro fertilization outcome. From July 1998 to July 1999, 224 patients underwent antral follicle assessment (follicle 2-6 mm in diameter) on baseline of the planned, stimulated in vitro fertilization cycle. The outcomes were analyzed with respect to antral follicle assessment (< or = 6 or > 6), basal cycle day 3 follicle stimulated hormone (< or = 10 or > 10 IU/L) and maternal age (< or = 35 or > 35 years). RESULTS: The clinical pregnancy rate was significantly higher in the group with baseline antral follicle > 6 compared to that in the group with antral follicle < or = 6 (51% vs. 19%, respectively). Controlling for patient age, and basal follicle stimulated hormone, the pregnancy rate was significantly higher in the group with antral follicle > 6 compared to that in the group with antral follicle < or = 6. The cancellation rate was significantly increased with advancing maternal age, elevated basal follicle stimulated hormone levels, and baseline antral follicle < or = 6. The cancellation rate was significantly higher in the group with antral follicle < or = 6 compared to that in the group with antral follicle > or = 6 (33% vs. 1%, respectively). CONCLUSIONS: In vitro fertilization outcome is strongly correlated with both maternal ages, basal cycle, day 3 follicle, stimulated hormone, and antral follicle assessment. Antral follicle assessment was a better predictor of in vitro fertilization outcome than were age or follicle stimulated hormone. Antral follicle assessment may provide a marker for ovarian age that is distinct from chronological age or hormonal markers.


Asunto(s)
Fertilización In Vitro , Hormona Folículo Estimulante/sangre , Folículo Ovárico/fisiología , Resultado del Embarazo , Adulto , Factores de Edad , Femenino , Humanos , Modelos Logísticos , Masculino , Folículo Ovárico/diagnóstico por imagen , Inducción de la Ovulación , Proyectos Piloto , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Ultrasonografía
15.
Endocrinology ; 140(6): 2641-4, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10342853

RESUMEN

The recent characterization of apoptotic protease-activating factor-1 (Apaf-1) in vertebrates as a putative homolog of the Caenorhabditis elegans gene, ced-4, indicates that the third major arm of the C. elegans programmed cell death machinery has also been conserved through evolution. Although apoptosis is now known to be important for ovarian follicular atresia in vertebrates, nothing is known of the role of Apaf-1 in ovarian function. Herein we show by immunohistochemical analysis that Apaf-1 is abundant in granulosa cells of early antral follicles whereas in vivo gonadotropin priming completely suppresses Apaf-1 expression and granulosa cell apoptosis. Western blot analysis of fractionated protein extracts prepared from granulosa cells before and after in vitro culture without hormonal support to induce apoptosis indicated that mitochondrial cytochrome c release, a biochemical step required for the activation of Apaf-1, occurs in granulosa cells cultured in vitro. Moreover, Western blot analysis of procaspase-3 processing, a principal downstream event set in motion by activated Apaf-1, indicated that healthy granulosa cells possess almost exclusively the inactive (pro-) form of the enzyme whereas granulosa cells deprived of hormonal support rapidly process procaspase-3 to the active enzyme. Lastly, we show that serum-starved granulosa cells activate caspase-3-like enzymes both prior to and after nuclear pyknosis, as revealed by a single-cell fluorescent caspase activity assay. These data, combined with previous observations regarding the role of homologs of the two other C. elegans cell death regulatory genes, ced-9 (Bcl-2 family members) and ced-3 (caspases), in atresia fully support the hypothesis that granulosa cell apoptosis is precisely coordinated by all three major arms of a cell death program conserved through evolution.


Asunto(s)
Apoptosis , Células de la Granulosa/química , Proteínas/análisis , Animales , Factor Apoptótico 1 Activador de Proteasas , Caspasa 3 , Caspasas/metabolismo , Células Cultivadas , Femenino , Células de la Granulosa/patología , Ratones , Proteínas/genética , ARN Mensajero/análisis
17.
Mol Hum Reprod ; 4(5): 483-9, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9665635

RESUMEN

In-vitro studies on mouse oocytes have shown that human follicular fluid and bull testes contain an activity which partially overrides the inhibitory action of hypoxanthine on meiosis. This activity was ascribed to two closely related sterols, subsequently named meiosis-activating sterols (MAS). We have used a potent inhibitor of sterol synthesis, ketoconazole, in order to test in vivo and in vitro whether MAS play a necessary physiological role in the resumption of meiosis in the rat. When administered systemically, ketoconazole (8.3-16.6 mg/rat) suppressed ovulation by 40%. Local unilateral administration of the drug into the ovarian bursa (1.25 mg/bursa) resulted in 75% inhibition of ovulation in comparison with the contralateral ovary. All the ovulated ova in the oviduct were mature. Histological examination of the ketoconazole-treated ovaries revealed mature oocytes trapped in follicles which failed to ovulate. Furthermore, extraction of oocytes from the large follicles of such ovaries revealed that 79% of them were mature. Addition of ketoconazole (0.0001-0.01 mM) to the culture medium did not affect significantly the spontaneous maturation of rat oocytes. However, ketoconazole at a higher concentration (0.1 mM) caused the degeneration of oocytes. Ketoconazole (0.01 mM) did not affect luteinizing hormone (LH)-stimulated oocyte maturation in explanted preovulatory follicles, even though it inhibited follicular progesterone production to levels below the hormone-free control follicles. At higher levels, ketoconazole caused the degeneration of follicles and the enclosed oocytes. In conclusion, using a potent inhibitor of MAS we have failed to confirm the suggested obligatory role of MAS in the resumption of meiosis in the rat both in vivo and in vitro.


Asunto(s)
Colestadienoles/antagonistas & inhibidores , Inhibidores Enzimáticos del Citocromo P-450 , Inhibidores Enzimáticos/farmacología , Cetoconazol/farmacología , Meiosis/efectos de los fármacos , Ovulación/efectos de los fármacos , Oxidorreductasas/antagonistas & inhibidores , Animales , Células Cultivadas , Femenino , Hormona Luteinizante/farmacología , Oocitos/efectos de los fármacos , Oogénesis/efectos de los fármacos , Técnicas de Cultivo de Órganos , Folículo Ovárico/efectos de los fármacos , Ovario/efectos de los fármacos , Progesterona/metabolismo , Ratas , Ratas Wistar , Esterol 14-Desmetilasa
19.
Biol Reprod ; 55(5): 1075-80, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8902220

RESUMEN

Atretic demise rather than ovulation is the ultimate fate of the vast majority of ovarian follicles in mammals, affecting 70-99.9% of the follicles in various species. Recent studies have established that atretic degeneration of follicles is an apoptotic process, heralded by endonuclease degradation of DNA at internucleosomal sites, which generates DNA fragments in size multiples of 185-200 bp that are seen as distinct ladder bands after agarose gel electrophoresis. Using the well-characterized model of inducing atresia of preovulatory follicles in vivo by hypophysectomy and analyzing DNA fragmentation by autoradiography of size-fractionated DNA labeled at the 3' ends by [12P] dideoxy-ATP, we have examined the timing of atretic changes. DNA degradation was related to morphological signs of atresia, ovulability, and changes in follicular steroidogenesis. Rats were hypophysectomized on the morning of the day of proestrus, after which largest follicles were collected at various times. DNA fragmentation was analyzed in groups of five follicles. The increase in DNA fragments of low molecular weight up to 4 h after hypophysectomy was negligible (101 +/- 10%; 0 h time = 100%) but progressed 8, 12, 24, 48, and 72 h after hypophysectomy (143 +/- 20%, 168 +/- 27%, 235 +/- 29%, 3299 +/- 1075%, and 2249 +/- 805%, respectively; p < 0.03, n = 5). At 48 and 72 h, the extent of DNA degradation was higher than that observed in follicles cultured in a serum-free medium for 24 h. Likewise, staining of DNA by 4',6-diamido-2-phenylindole hydrochloride revealed apoptotic nuclei at 8 h after hypophysectomy (p < 0.01), and the percentage of such nuclei progressively increased afterwards. Thus, the increase in DNA fragmentation appeared concomitantly with atretic changes observed in previous studies (a decrease in ovulability at 6 h, and a spontaneous increase in progesterone accumulation and decrease in androgen and estrogen in follicles explanted 6 h after hypophysectomy) and preceded atresia detectable by morphological changes at 24 h. Detection of internucleosomal DNA degradation in preovulatory follicles early in the atretic cascade underscores the central role of apoptosis in ovarian follicle atresia.


Asunto(s)
Fragmentación del ADN , Atresia Folicular , Ovulación , Animales , Autorradiografía , Núcleo Celular/ultraestructura , Medio de Cultivo Libre de Suero , Técnicas de Cultivo , Femenino , Células de la Granulosa/ultraestructura , Hipofisectomía , Ratas , Ratas Wistar
20.
Hum Reprod ; 10(1): 75-81, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7745074

RESUMEN

The association between hyperinsulinaemia and hyperandrogenism in many women with polycystic ovarian syndrome (PCOS) implies roles for insulin and insulin-like growth factors (IGFs) in the regulation of ovarian androgen production. The aim of the present study was to compare the abilities of insulin, IGF-I and IGF-II to stimulate androgen production by human thecal cells in vitro. Serum-free monolayer cell cultures were established from the ovaries of euandrogenic women undergoing hysterectomy with oophorectomy for non-ovarian indications. Androgen (androstenedione) production was determined after 4 days of culture in the presence of insulin or either of the IGFs (10-100 ng/ml), with and without a maximal stimulatory dose of luteinizing hormone (LH; 10 ng/ml). Interactions with inhibin (30 ng/ml), a putative paracrine regulator of ovarian androgen synthesis, were also tested. The three metabolic hormones exerted similar dose-related effects on androgen production (ED50 < or = 10 ng/ml), which were augmented 2- to 3-fold in the presence of LH and further increased several-fold by the additional presence of inhibin. No treatment with insulin or either IGF stimulated thecal cell growth, but all treatments caused striking morphological changes consistent with enhanced steroidogenesis. These results reveal potent regulatory effects of metabolic hormones on human thecal androgen synthesis, which imply (i) 'progonadotrophic' roles for insulin and IGF-I in regulating normal ovarian androgen production, (ii) a role for insulin in the aetiology of hyperandrogenism (both with and without hyperinsulinism) in PCOS and (iii) paracrine roles for granulosa-derived IGF-II and inhibin in regulating ovarian androgen production.


Asunto(s)
Androstenodiona/biosíntesis , Células Tecales/metabolismo , Adulto , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Hiperandrogenismo/etiología , Hiperandrogenismo/metabolismo , Técnicas In Vitro , Inhibinas/farmacología , Insulina/administración & dosificación , Insulina/metabolismo , Insulina/farmacología , Factor I del Crecimiento Similar a la Insulina/administración & dosificación , Factor I del Crecimiento Similar a la Insulina/farmacología , Factor II del Crecimiento Similar a la Insulina/administración & dosificación , Factor II del Crecimiento Similar a la Insulina/farmacología , Hormona Luteinizante/administración & dosificación , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/metabolismo , Proteínas Recombinantes/administración & dosificación , Células Tecales/citología , Células Tecales/efectos de los fármacos
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