RESUMEN
Preliminary data have shown that it is possible to attempt in vitro fertilization (IVF) treatment in fresh cycles without the use of a gonadotropin-releasing hormone (GnRH) antagonist or any other medication to prevent the luteinizing hormone (LH) surge during ovarian stimulation. To date, there is no information on this topic in the context of a prospective controlled trial. However, as prevention of the LH surge is an established procedure in fresh cycles, the question is whether such a study can be performed in frozen cycles. We aim to perform a pilot study in order to compare the efficacy of a protocol using FSH alone with that of a protocol using follicle-stimulating hormone (FSH) plus a GnRH antagonist for controlled ovarian hyperstimulation (COH) in cycles of elective freezing in the context of a donor/recipient program. This is a seven-center, two-arm prospective pilot cohort study conducted at the respective Assisted Reproductive Units in Greece. The hypothesis to be tested is that an ovarian stimulation protocol that includes FSH alone without any LH surge prevention regimens is not inferior to a protocol including FSH plus a GnRH antagonist in terms of the clinical outcome in a donor/recipient model. The results of the present study are expected to show whether the addition of the GnRH antagonist is necessary in terms of the frequency of LH secretory peaks and progesterone elevations >1 ng/mL during the administration of the GnRH antagonist according to the adopted frequency of blood sampling in all Units.
RESUMEN
Health inequalities adversely affect the health outcomes generally but more so for those who are socially deprived, immigrants of unknown status and low socioeconomic status. The inequitable access to care during pregnancy can lead to long term adverse inter-generational effects. Current economic crisis within Europe will have deepening effect on the health of the vulnerable families. The European Board and College of Obstetrics and Gynaecology calls for action by the European Union.
Asunto(s)
Ginecología , Obstetricia , Femenino , Embarazo , Humanos , Atención Prenatal , Europa (Continente) , Unión Europea , Factores SocioeconómicosRESUMEN
Despite advances in promoting sexual and reproductive rights by the United Nations, WHO and UNFPA, inequities in the provision of health care for women exist and are influenced by the socioeconomic status and the ethnicity and the migrant status. Of late, Human Fertility and Embryology Authority (HFEA) of the United Kingdom has identified that inequities exists in quality, accessibility and outcomes of fertility services for people of colour in the UK. EBCOG calls upon the EU Commission to set up a monitoring system akin to HFEA to ensure that all citizens of Europe not only enjoy equitable access to fertility treatments but also the outcomes of interventions meet the highest standards of care.
Asunto(s)
Fertilidad , Pigmentación de la Piel , Femenino , Humanos , Derechos Sexuales y Reproductivos , Técnicas Reproductivas Asistidas , Reino UnidoRESUMEN
Ιnformation on the role of adiponectin in human ovarian steroidogenesis is limited. The present study aimed to investigate the effect of different doses of adiponectin on the secretion of estradiol and progesterone by human luteinized granulosa cells in culture. Granulosa cells, obtained from women undergoing in vitro fertilization (IVF) treatment, were pre-incubated for 24 h and then cultured for 48 h. Adiponectin was used in 3 doses, i.e., 5, 10, and 100 µg/ml alone and in combinations with FSH (10 and 100 ng/ml). Estradiol and progesterone were measured by radioimmunoassays in culture supernatants at 24 h and 48 h. Adiponectin after 48 h of culture stimulated the secretion of estradiol and, to a lesser extent, progesterone in a dose-dependent manner. FSH showed a variable effect on steroidogenesis. However, when the low dose FSH was combined with adiponectin, estradiol, and progesterone secretion were increased disproportionally to the dose of adiponectin. With the high dose FSH, the positive effect of adiponectin on FSH-induced estradiol secretion was less pronounced, while the effect on progesterone secretion was negligible. This study shows for the first time a stimulatory effect of adiponectin on the secretion of estradiol and progesterone by human luteinized granulosa cells in vitro. It is suggested that adiponectin plays a paracrine role in human ovarian steroidogenesis by sensitizing the granulosa cells to FSH.
Asunto(s)
Adiponectina , Progesterona , Células Cultivadas , Estradiol , Femenino , Hormona Folículo Estimulante , Células de la Granulosa , HumanosRESUMEN
The COVID-19 pandemic, caused by the SARS-CoV-2 virus, is an unprecedented global situation, and all countries have adopted their own measurements to mitigate the spread of the virus in the first as well as in the subsequent waves of infection. All measures, especially in the first wave of the pandemic, were in combination with recommendations provided by professional and scientific organizations. Similar measures were applied to specific procedures, such as the management of infertility, including in vitro fertilization-embryo transfer (IVF-ET) treatments. Although there is no clear scientific evidence yet that the SARS-CoV-2 may exert negative effects on IVF outcome, especially at the early stages, several clinical reports indicate that the virus may impact male fertility through specific receptors presented at the somatic cells of the testis and used by the virus in order to gain entry to the respective cells. Nevertheless, it is not unreasonable to suspect that the virus may affect sperm function as well as oocyte performance directly through specific receptors or indirectly through other signaling pathways. Despite the good practice of IVF laboratory techniques, culture media may also be contaminated during equilibration when airborne virus's particles can contaminate culture media from an already infected embryology area or staff. Furthermore, although there is no clinical evidence, liquid nitrogen could be a route of infection for gametes and embryos when it has been contaminated during production or transportation. Therefore, cryopreservation of gametes and embryos must be virus-free. This communication aims to provide some aspects of the possible impact of the virus on gametes and embryos and how it may affect the cryopreservation procedures.Abbreviations: ACE2: angiotensin- converting enzyme 2; ART: assisted reproductive technology; ASRM: American Society for Reproductive Medicine; CDC: Centers for Disease Control and Prevention; COVID-19: coronavirus disease 2019; ESHRE: European Society of Human Reproduction and Embryology; ET: embryo transfer; FSH: follicle stimulating hormone; IFFS: International Federation of Fertility Societies; IVF: in vitro fertilization; LH: luteinizing hormone; LN: liquid nitrogen; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2; T: testosterone; WHO: World Health Organization.
Asunto(s)
Blastocisto/virología , COVID-19/virología , Criopreservación , Infertilidad/terapia , Oocitos/virología , Técnicas Reproductivas Asistidas , SARS-CoV-2/patogenicidad , Espermatozoides/virología , COVID-19/diagnóstico , COVID-19/transmisión , Transferencia de Embrión , Femenino , Fertilización In Vitro , Humanos , Infertilidad/diagnóstico , Infertilidad/fisiopatología , Masculino , Embarazo , Técnicas Reproductivas Asistidas/efectos adversosRESUMEN
During ovarian stimulation for IVF-embryo transfer treatment, a premature LH surge may lead to progesterone elevation that disrupts endometrial maturation and affects the probability of pregnancy following fresh embryo transfer. Preventing this LH surge and progesterone elevation using gonadotrophin-releasing hormone (GnRH) analogues is considered a standard practice. The same policy applies to cycles in which the 'freeze-all' protocol has been selected from the outset (e.g. donors), but the need for this has not been discussed. Moreover, in 'freeze-all' cycles, exogenous progesterone administration tends to replace GnRH antagonists, without reducing efficacy after embryo transfer in frozen-thawed cycles. Nevertheless, as exogenous progesterone is expected to have the same impact on the endometrium as endogenous progesterone, it is clear that, unlike in fresh cycles, in 'freeze-all' cycles an endogenous LH surge prevention does not seem necessary. Therefore, both GnRH antagonists and exogenous progesterone appear to be redundant in 'freeze-all' cycles, and in this context the indications for the use of GnRH analogues in ovarian stimulation protocols need to be revisited.
Asunto(s)
Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Hormona Luteinizante/sangre , Inducción de la Ovulación/métodos , Progesterona/administración & dosificación , Femenino , Hormona Liberadora de Gonadotropina/análogos & derivados , HumanosRESUMEN
The COVID-19 pandemic is an extraordinary global situation, and all countries have adopted their own strategies to diminish and eliminate the spread of the virus. All measures are in line with the recommendations provided by the World Health Organization. Scientific societies, such as the European Society for Human Reproduction and Embryology and American Society for Reproductive Medicine, have provided recommendations and guidance to overcome and flatten the growing curve of infection in patients who undergo IVF treatments. Although there is as yet no evidence that the virus causing COVID-19 might have negative effects on IVF outcomes, fertility treatments have been postponed in order to support healthcare systems by avoiding placing them under additional stress. The possibility of the virus affecting sperm function and egg performance cannot be excluded. In addition, an indirect effect of the virus on gametes and embryos during their manipulation cannot be ruled out. This commentary aims to provide some ideas on the possible effect of the virus on gametes and embryos, as well as how it could affect the normal functioning of the embryology laboratory.
Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/prevención & control , Fertilidad , Pandemias/prevención & control , Neumonía Viral/prevención & control , Técnicas Reproductivas Asistidas/estadística & datos numéricos , Betacoronavirus/fisiología , COVID-19 , Infecciones por Coronavirus/epidemiología , Embrión de Mamíferos/virología , Femenino , Clínicas de Fertilidad/estadística & datos numéricos , Fertilización In Vitro/métodos , Fertilización In Vitro/estadística & datos numéricos , Humanos , Masculino , Oocitos/virología , Neumonía Viral/epidemiología , Embarazo , SARS-CoV-2 , Espermatozoides/virología , Resultado del TratamientoRESUMEN
Information on the role of resistin on steroidogenesis is limited to animal studies. The aim of this study was to investigate the effect of various doses of resistin on estradiol and progesterone secretion from human luteinized granulosa cells in culture. Granulosa cells were obtained from follicular fluid aspirated from 50 women undergoing in vitro fertilization (IVF) treatment. The cells were cultured for 48 h after a 24 h pre-incubation period. The effect of resistin at dosages 1, 10 and 100 ng/ml alone or in combinations with FSH (10 and 100 ng/ml) on steroidogenesis was investigated. Estradiol and progesterone were measured by radioimmunoassays in culture supernatants at 24 h and 48 h. FSH treatment increased both estradiol and progesterone secretion. Resistin suppressed basal estradiol (at 1 ng/ml) and progesterone secretion (at all concentrations tested). When resistin (all concentrations) was combined with FSH (100 ng/ml), it eliminated the stimulatory effect of FSH on the secretion of estradiol and progesterone. This study indicates an inhibitory effect of resistin on the secretion of estradiol and progesterone by human luteinized granulosa cells in vitro. It is likely that this adipokine locally affects ovarian function in women. Abbreviations: 3ß-HSD: 3ß-hydroxysteroid dehydrogenase; CAP1: cyclase-associated protein 1; DCN: decorin; FIZZ: Found in Inflammatory Zones; hCG: human chorionic gonadotropin; IGF1: insulin-like growth factor type 1; IVF: in vitro fertilization; PCOS: polycystic ovary syndrome; RIA: radioimmunoassay; ROR1: receptor tyrosine kinase-like orphan receptor-1; TLR4: Toll-like receptor 4.
Asunto(s)
Estradiol/metabolismo , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Progesterona/metabolismo , Resistina/farmacología , Adulto , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Fertilización In Vitro , Hormona Folículo Estimulante/farmacología , HumanosRESUMEN
RESEARCH QUESTION: Ganirelix is a gonadotrophin-releasing hormone (GnRH) antagonist used for the prevention of premature LH surge during ovarian stimulation. What is the impact of ganirelix on follicle maturation in normal women? DESIGN: Ten normally cycling women were investigated during two menstrual cycles, i.e. cycle 1 (control) and cycle 2 (ganirelix). During both cycles, daily blood samples were taken from day 2, while transvaginal ultrasound scans were performed on cycle days 8 and 10 and daily thereafter. During cycle 2, all women were given 0.25 mg/day subcutaneous injections of the GnRH antagonist ganirelix from day 2 until the day of the endogenous LH surge onset in cycle 1. RESULTS: During treatment with ganirelix, serum FSH and oestradiol concentrations remained stable, while those of LH decreased significantly on days 3, 4, 7 and 9 (P < 0.05) compared with controls. Nevertheless, there was no significant within-cycle variation in LH concentrations. From day 10 onwards, no follicle maturation was observed in cycle 2, in contrast to cycle 1. Ovulation occurred in 9 of 10 women in cycle 1. In cycle 2, ovulation was delayed by at least 1 week in eight women. Follicle growth and ovulation occurred in only one woman while on ganirelix treatment. CONCLUSIONS: This study demonstrates for the first time that in normal women dominant follicle selection failed during treatment with ganirelix. As there was a similar gonadotrophin profile in the two cycles, it is suggested that ganirelix interferes with the process of follicle selection by acting in the ovary.
Asunto(s)
Fase Folicular/efectos de los fármacos , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Antagonistas de Hormonas/farmacología , Folículo Ovárico/efectos de los fármacos , Adulto , Tamaño de la Célula/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/sangre , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/farmacología , Voluntarios Sanos , Antagonistas de Hormonas/administración & dosificación , Humanos , Inyecciones Subcutáneas , Hormona Luteinizante/sangre , Folículo Ovárico/fisiología , Ovario/citología , Ovario/efectos de los fármacos , Ovario/fisiología , Ovulación/efectos de los fármacos , Adulto JovenRESUMEN
OBJECTIVES: To investigate the effect of metformin on endometrial receptivity in women with polycystic ovary syndrome (PCOS). METHODS: Twenty volunteer women with polycystic ovaries and oligomenorrhea were prospectively investigated. All women were treated with exogenous estradiol and progesterone to simulate a normal menstrual cycle (28-day duration) after GnRH-induced pituitary desensitization. Ten of the women received no other medication (group A, control), while the remaining 10 received metformin (group B, metformin). Endometrial biopsy was performed in all women on day 21 of the 2 simulated cycles. RESULTS: The expression of corticotropin - releasing hormone and urocortin in the endometrium was investigated. There was no significant difference between the 2 groups. A 3-day delay in the secretory maturation of the glandular epithelium relatively to the stroma was observed in 7 out of 10 women of group B (70%) as compared to only 1 out of 10 women of group A (10%, p = 0.02). CONCLUSIONS: It is shown for the first time that metformin administration to women with PCOS did not affect the expression of endometrial receptivity markers but delayed histological glandular maturation. It is suggested that metformin may have an impact on the function of the endometrium in PCOS.
Asunto(s)
Endometrio/efectos de los fármacos , Endometrio/fisiopatología , Hipoglucemiantes/farmacología , Metformina/farmacología , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Adulto , Hormona Liberadora de Corticotropina/metabolismo , Quimioterapia Combinada , Endometrio/patología , Estradiol/uso terapéutico , Estrógenos/uso terapéutico , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Metformina/uso terapéutico , Oligomenorrea/etiología , Síndrome del Ovario Poliquístico/complicaciones , Progesterona/uso terapéutico , Progestinas/uso terapéutico , Estudios Prospectivos , Urocortinas/metabolismoRESUMEN
Gonadotropin surge-attenuating factor (GnSAF) is a nonsteroidal ovarian substance, which attenuates the endogenous LH surge in superovulated women. Different molecular sequences have been found, but only one of them has shown substantial homology to a known substance of the human genome. A molecular mass of 12.5kDa showing identity to the carboxyl-terminal fragment of human serum albumin and expressing GnSAF bioactivity in vitro has been identified. It has been suggested that in the normal menstrual cycle the in vivo bioactivity of GnSAF increases under the influence of the intercycle rise of FSH. GnSAF is considered the "missing link" between the ovaries and the hypothalamo-pituitary system, maintaining the pituitary in a state of low responsiveness to GnRH in the early- to midfollicular phase of the cycle. A marked decline in GnSAF bioactivity in the late follicular phase facilitates the onset and the full expression of the midcycle LH surge.
Asunto(s)
Hormonas Gonadales/metabolismo , Hormona Liberadora de Gonadotropina/metabolismo , Gonadotropinas/antagonistas & inhibidores , Sistema Hipotálamo-Hipofisario/fisiología , Ciclo Menstrual/metabolismo , Modelos Biológicos , Ovario/fisiología , Proteínas/metabolismo , Animales , Ciclo Estral/sangre , Ciclo Estral/metabolismo , Retroalimentación Fisiológica , Femenino , Fase Folicular/sangre , Fase Folicular/metabolismo , Hormonas Gonadales/aislamiento & purificación , Gonadotropinas/metabolismo , Humanos , Sistema Hipotálamo-Hipofisario/metabolismo , Ciclo Menstrual/sangre , Oogénesis , Ovario/metabolismo , Proteínas/aislamiento & purificaciónRESUMEN
OBJECTIVE: An inhibitory effect of ghrelin on gonadotrophin secretion has been reported in normally menstruating women possibly modulated by endogenous oestrogen. The aim of this study was to examine the effect of ghrelin on gonadotrophin and prolactin (PRL) secretion in oestrogen-deprived postmenopausal women. DESIGN: Prospective intervention study. PATIENTS AND MEASUREMENTS: Ten healthy postmenopausal volunteer women were studied during two 15-days periods of oestrogen treatment (A and B) a month apart. Four experiments (Exp) were performed in total, two on day 1 (Exp 1A and Exp 1B) and two on day 15 (Exp 15A and Exp 15B) of the two periods. The women received in Exp 1A and in Exp 15A two iv injections of ghrelin (0.15 µg/kg at time 0 minute and 0.30 µg/kg at time 90 minutes) and in Exp1B and in Exp 15B normal saline (2 mL), respectively. Blood samples were taken at -15, 0, 30, 60, 90, 120, 150 and 180 minutes. RESULTS: After oestrogen treatment, late follicular phase serum oestradiol levels were attained on day 15 of periods A and B. Ghrelin administration did not affect serum levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), whereas it increased significantly those of growth hormone (GH) and PRL. In Exp 15A, serum PRL increment in response to ghrelin (area under the curve, net increment) was significantly greater than in Exp 1A (P<.05). CONCLUSIONS: This study demonstrates for the first time that in oestrogen-deprived postmenopausal women, ghrelin administration affects neither FSH nor LH levels but stimulates PRL secretion, that is amplified by exogenous oestrogen administration.
Asunto(s)
Estrógenos/administración & dosificación , Ghrelina/administración & dosificación , Gonadotropinas/antagonistas & inhibidores , Posmenopausia/efectos de los fármacos , Prolactina/metabolismo , Anciano , Femenino , Hormona Folículo Estimulante/sangre , Ghrelina/farmacología , Humanos , Hormona Luteinizante/sangre , Persona de Mediana Edad , Posmenopausia/sangre , Prolactina/efectos de los fármacos , Estudios ProspectivosRESUMEN
The purpose of this study was to investigate the possible molecular pathways through which ghrelin accelerates in vitro oocyte maturation. Bovine cumulus-oocyte complexes (COCs), after 18 or 24 h maturation in the absence or the presence of 800 pg ml-1 of acylated ghrelin were either assessed for nuclear maturation or underwent in vitro fertilization in standard media and putative zygotes were cultured in vitro for 8 days. In a subset of COCs the levels of phosphorylated Akt1 and ERK1/2 (MAPK1/3) were assessed at the 0th, 6th, 10th, 18th and 24th hours of in vitro maturation (IVM). At 18 and 24 h no difference existed in the proportion of matured oocytes in the ghrelin-treated group, while in the control group more (P < 0.05) matured oocyte were found at 24 h. Oocyte maturation for 24 h in the presence of ghrelin resulted in substantially reduced (P < 0.05) blastocyst yield(16.3%) in comparison with that obtained after 18 h (30.0%) or to both control groups (29.3% and 26.9%, for 18 and 24 h in maturation, respectively). Ghrelin-treated oocytes expressed lower Akt1 phosphorylation rate at the 10th hour of IVM, and higher ERK1/2 at the 6th and 10th hours of IVM compared with controls. In cumulus cells, at the 18th and 24th hours of IVM Akt1 phosphorylation rate was higher in ghrelin-treated oocytes. Our results imply that ghrelin acts in a different time-dependent manner on bovine oocytes and cumulus cells modulating Akt1 and ERK1/2 phosphorylation, which brings about acceleration of the oocyte maturation process.
Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Ghrelina/farmacología , Técnicas de Maduración In Vitro de los Oocitos/métodos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Oocitos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Bovinos , Células Cultivadas , Células del Cúmulo/citología , Células del Cúmulo/efectos de los fármacos , Células del Cúmulo/metabolismo , Femenino , Oocitos/citología , Oocitos/efectos de los fármacosRESUMEN
Infertility is a global medical problem of the reproductive system which may affect the quality of a woman's life. Whether infertility provision varies between different European countries has not been investigated in the context of a comparative study. There are, however, differences in legislation between different countries, which encourage "infertility tourism". Women cross borders in order to get access to those treatment modalities that are not provided in their own country. Oocyte donation for example and the high cost of the services locally are common reasons for this mobility. Although treatment of infertility is still aetiology based, unexplained cause is most often the underlying reason. The invention of in vitro fertilisation (IVF) has changed the management of infertility globally. In most European countries, treatment is mainly provided by well-organised private IVF centres using highly effective methodologies. Different European scientific organisations, together with European Board and College of Obstetrics and Gynaecology (EBCOG), should provide recommendations to the European Union on the development of common legislation to streamline quality assured clinical care for infertile couples. This will hopefully help to eliminate possible inequalities, providing evidence based services according to patients' needs and also reduce the cross border healthcare demand in European countries.
RESUMEN
Evidence-based medicine is the principal approach to medical practice. There are several debatable issues in infertility, which require clarification. Over the past 20 years, reliable methodology has been developed for the management of infertile couples. This includes high quality diagnostic and therapeutic procedures, which are applied in highly specialised infertility centres. The European Board and College of Obstetrics and Gynaecology (EBCOG) has published Standards of Care for Women's Health in Europe, which should be the cornerstone for the clinicians and service providers in the European Union to establish common protocols within their centres. Each infertility treatment should result in the highest possible success rate and all appropriate measures for the patient's safety should be in place. The treatment protocols should minimise risk of complications, such as ovarian hyperstimulation syndrome (OHSS). The current use of GnRH agonists to trigger final follicle maturation has provided the means for avoiding this syndrome. Additionally, multiple pregnancy rates are still high in assisted reproductive technology (ART). These rates should be reduced by the adoption of single embryo transfer during IVF treatment and by the proper monitoring of ovulation induction protocols. EBCOG Standards of Care for infertility and assisted conception treatment derived from the best available evidence should underpin the provision of high quality infertility services in European countries.
RESUMEN
The purpose of this study was to evaluate the predictive value of free sperm plasma DNA (f-spDNA) and sperm DNA fragmentation (SDF), in semen specimens from men undergoing in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) treatments. Fifty-five semen samples were evaluated during 55 consecutive IVF/ICSI-ET cycles. F-spDNA was determined by conventional quantitative real-time PCR-Sybr green detection approach, while evaluation of sperm DNA damage was performed using the sperm chromatin dispersion (SCD) assay. While f-spDNA only correlated with total sperm count, SDF correlated with many semen parameters (including sperm concentration, total sperm count and the per cent of non-progressive sperm). Neither SDF nor the proportion of sperm with small or no halos correlated with f-spDNA. Interestingly, smoking status correlated with f-spDNA but not with SDF. Although these two factors seem to interact for the prediction of pregnancy, receiver-operating characteristics (ROC) analysis revealed that SDF had a stronger predictive value (AUC = 0.7, p < 0.05) than f-spDNA (AUC = 0.6, p > 0.05). SDF and f-spDNA may not be associated together but they interact at a significant level in order to exert their actions on pregnancy outcome. Among the two markers, SDF appears to have stronger and significantly predictive value for pregnancy success.
Asunto(s)
Fragmentación del ADN , ADN/metabolismo , Implantación del Embrión , Transferencia de Embrión , Fertilización In Vitro , Infertilidad Masculina/terapia , Espermatozoides/metabolismo , Adulto , Biomarcadores/metabolismo , Composición Familiar , Femenino , Grecia , Hospitales Universitarios , Humanos , Infertilidad Masculina/diagnóstico , Infertilidad Masculina/metabolismo , Masculino , Embarazo , Pronóstico , Reacción en Cadena en Tiempo Real de la Polimerasa , Semen/metabolismo , Recuento de Espermatozoides , Inyecciones de Esperma Intracitoplasmáticas , Motilidad EspermáticaRESUMEN
It is well known that for successful fertilization, oocyte activation is required, which involves a signal transduction cascade leading to the conversion of the oocyte to a diploid embryo. During oocyte activation, intracellular calcium levels oscillate repetitively causing exocytosis of cortical granules, the enzymes which the latter contain are released into the perivitelline space, leading to modifications of the zona pellucida (ZP), which prevent the penetration of the ZP by further spermatozoa. The necessary element that initiates oocyte activation is apparently the release of intracellular calcium (Ca(2+)) stored in the endoplasmic reticulum (ER). The exact mechanism via which Ca(2+) is released within the oocyte has not been yet clarified, and has been a matter of an ongoing debate. Today, the sperm factor hypothesis has gained general acceptance, according to which a sperm molecule, either phospholipase C (PLCζ) or a post-acrosomal sheath WW domain-binding protein (PAWP), diffuses into the ooplasm initiating a molecular cascade involving mainly the phosphoinositide pathway. Mounting evidence now indicates that these calcium oscillations are caused by a testis-specific PLC termed PLCζ, released into the oocyte following gamete fusion. Also, recently, PAWP has been proposed as an alternative sperm factor candidate. These different sperm candidates have led to a significant debate. This raises important questions as regards to the relative importance of these two proteins as diagnostic tools in reproductive medicine with therapeutic potential, indicating the need for further research. In the present mini review, the phenomenon of oocyte activation during fertilization as well as the existing controversy will be highlighted and the possible mechanisms that are involved in this process will be discussed. Finally, an explanation of the existing debate will be attempted.
Asunto(s)
Proteínas Portadoras/metabolismo , Oocitos/fisiología , Fosfoinositido Fosfolipasa C/metabolismo , Proteínas de Plasma Seminal/metabolismo , Interacciones Espermatozoide-Óvulo/fisiología , Espermatozoides/fisiología , Animales , Señalización del Calcio , Fertilización/fisiología , Fertilización In Vitro , Humanos , Isoenzimas/metabolismo , Masculino , Espermatozoides/citologíaRESUMEN
PURPOSE: MLH3, a MutL homolog protein in mammals playing a role in DNA mismatch repair, is associated with spermatogenesis and male infertility. The purpose of the present study was to investigate the association of the single-nucleotide polymorphism (SNP), rs 175080 in the MLH3 gene, with sperm parameters in a Greek population. METHODS: The study included 300 men of couples undergoing in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) treatments (years 2011-2013). Genomic DNA was extracted from 300 peripheral blood samples, and conventional quantitative real-time PCR was performed for genotyping. Of them, 122 were from men used as "controls" and 178 from men used as "cases." Allocation to the two groups was based on sperm concentrations (≥15 and <15 million/ml, respectively). Serum FSH, LH, estradiol, testosterone, and prolactin concentrations as well as sperm parameters were compared between three genotypes (GG, GA, and AA). Furthermore, the frequencies of these three genotypes were compared between "cases" and "controls." RESULTS: Anthropometric parameters and hormonal values did not differ significantly between the three genotypes. Significantly lower sperm concentrations were found in men with the AA genotype as compared to men with the GG and GA genotypes (p < 0.001). The AA genotype had the lower progressive motility values as compared to the other two genotypes (p < 0.05). Also, there was a significantly different distribution of the frequencies of the three genotypes between "cases" and "controls" (p < 0.001). CONCLUSIONS: It is suggested that the studied SNP in the MLH3 gene may be linked to oligozoospermia in Caucasian men of a certain area.
Asunto(s)
Proteínas Portadoras/genética , Infertilidad Masculina/genética , Polimorfismo de Nucleótido Simple , Adulto , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Proteínas MutL , Oligospermia/genética , Análisis de SemenRESUMEN
PURPOSE: To determine if there is any effect of AMH and BMP-15 on estradiol and progesterone production from primary-cultured human luteinizing granulosa cells, to delineate what is the effect of FSH on their actions and which are the possible mechanisms involved. METHODS: Luteinizing granulosa cells (GCs), obtained from follicular fluid of 30 women undergoing in vitro fertilization, were cultured, after a short 24-h preincubation period, in serum-free medium for 24 or/and 48 h in the presence/absence of various concentrations of AMH, BMP-15 and FSH alone or in combinations. Estradiol and progesterone production, SMAD5 phosphorylation and StAR expression were studied in parallel. Steroids were measured in culture-supernatant using enzyme-immunoassays, while Smad5-signaling pathway activation and StAR protein expression were assessed immunocytochemically. RESULT(S): We found that the treatment of AMH in GCs for 24/48 h attenuated FSH-induced estradiol production (p < 0.001), had no effect on basal estradiol levels, decreased basal progesterone production (p < 0.001) and FSH-induced StAR expression (p < 0.001). On the other hand, BMP-15 decreased basal estradiol levels (p < 0.001) and attenuated FSH-induced estradiol production (p < 0.001). Furthermore, BMP-15 reduced progesterone basal secretion (p < 0.001), an effect that was partially reversed by FSH (p < 0.01), probably via increasing StAR expression (p < 0.001). FSH-induced StAR expression was also attenuated by BMP-15 (p < 0.001). FSH, AMH and BMP-15 activated Smad-signaling pathway, as confirmed by the increase of phospo-Smad5 protein levels (p < 0.001 compared to control). CONCLUSION(S): AMH and BMP-15 by interacting with FSH affect the production of estradiol and progesterone from cultured luteinizing-granulosa cells possibly via Smad5-protein phosphorylation.