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1.
Hum Reprod ; 31(5): 977-85, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26956551

RESUMO

STUDY QUESTION: Does pretreatment with transdermal testosterone increase the number of cumulus-oocyte complexes (COCs) retrieved by more than 1.5 in poor responders undergoing intracytoplasmic sperm injection (ICSI), using recombinant follicle stimulating hormone (FSH) and gonadotrophin releasing hormone agonists (GnRHa)? SUMMARY ANSWER: Testosterone pretreatment failed to increase the number of COCs by more than 1.5 as compared with no pretreatment in poor responders undergoing ICSI (difference between medians: 0.0, 95% CI: -1.0 to +1.0). WHAT IS KNOWN ALREADY: Androgens are thought to play an important role in early follicular development by enhancing ovarian sensitivity to FSH. In a recent meta-analysis, testosterone pretreatment resulted in an increase of 1.5 COCs as compared with no pretreatment. However, this effect was based on the analysis of only two randomized controlled trials (RCTs) including 163 patients. Evidently, there is a need for additional RCTs that will allow firmer conclusions to be drawn. STUDY DESIGN, SIZE, DURATION: The present RCT was designed to detect a difference of 1.5 COCs (sample size required = 48 patients). From 02/2014 until 04/2015, 50 poor responders fulfilling the Bologna criteria have been randomized (using a randomization list) to either testosterone pretreatment for 21 days ( ITALIC! n = 26) or no pretreatment ( ITALIC! n = 24). PARTICIPANTS/MATERIALS, SETTING, METHODS: All patients underwent a long follicular GnRHa protocol. Recombinant FSH stimulation was started on Day 22 following GnRHa initiation. In the testosterone pretreatment group, a daily dose of 10 mg of testosterone gel was applied transdermally for 21 days starting from GnRHa initiation. Results are expressed as median (interquartile range). MAIN RESULTS AND THE ROLE OF CHANCE: No differences in baseline characteristics were observed between the two groups compared. Testosterone levels [median (interquartile range)] were significantly higher in the testosterone pretreatment on the day of initiation of FSH stimulation [114 (99.5) ng/dl versus 20 (20) ng/dl, respectively, ITALIC! P < 0.001]. Duration of FSH stimulation [median (interquartile range)] was similar between the groups compared [12.5 (3.0) days versus 12 (3.0) days, respectively, ITALIC! P = 0.52]. The number of COCs retrieved [median (interquartile range)] was not different between the testosterone pretreatment and the no pretreatment groups [3.5 (4.0) versus 3.0 (3.0), 95% CI for the median: 2.0-5.0 versus 2.7-4.3, respectively; difference between medians: 0.0, 95% CI: +1.0 to -1.0). Similarly no differences were observed regarding fertilization rates [median (interquartile range)] [66.7% (32.5) versus 66.7% (42.9), respectively, ITALIC! P = 0.97] and live birth rates per randomized patient (7.7% versus 8.3%, respectively, rate difference: -0.6%, 95% CI: -19.0 to +16.9). LIMITATIONS, REASONS FOR CAUTION: The study was not powered to detect differences less than 1.5 COCs, although it is doubtful whether these differences would be clinically relevant. Moreover, due to sample size restrictions, no conclusions can be drawn regarding the probability of live birth. WIDER IMPLICATIONS OF THE FINDINGS: The results of this randomized clinical trial, suggesting that pretreatment with 10 mg of transdermal testosterone for 21 days does not improve ovarian response by more than 1.5 oocytes, could be used to more accurately consult patients with poor ovarian response. However, an improvement in IVF outcome using a higher dose of testosterone or a longer pretreatment period cannot be excluded. STUDY FUNDING/COMPETING INTEREST: The study was partially funded by a Scholarship from the Academy of Athens. C.A.V. reports personal fees and non-financial support from Merck, Sharp and Dome, personal fees and non-financial support from Merck Serono, personal fees and non-financial support from IPSEN Hellas S.A., outside the submitted work. B.C.T. reports grants from Merck Serono, grants from Merck Sharp & Dohme, personal fees from Merck Serono, personal fees from Merck Sharp & Dohme, personal fees from IBSA & Ferring, outside the submitted work. TRIAL REGISTRATION NUMBER: NCT01961336. TRIAL REGISTRATION DATE: 10 October 2013. DATE OF FIRST PATIENT'S ENROLLMENT: 02/2014.


Assuntos
Administração Cutânea , Recuperação de Oócitos/métodos , Injeções de Esperma Intracitoplásmicas , Testosterona/uso terapêutico , Adulto , Feminino , Hormônio Foliculoestimulante/uso terapêutico , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Oócitos/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Indução da Ovulação/métodos , Testosterona/administração & dosagem , Resultado do Tratamento
2.
Curr Genomics ; 16(1): 32-46, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25937812

RESUMO

Embryo quality during the in vitro developmental period is of great clinical importance. Experimental genetic studies during this period have demonstrated the association between specific gene expression profiles and the production of healthy blastocysts. Although the quality of the oocyte may play a major role in embryo development, it has been well established that the post - fertilization period also has an important and crucial role in the determination of blastocyst quality. A variety of genes (such as OCT, SOX2, NANOG) and their related signaling pathways as well as transcription molecules (such as TGF-ß, BMP) have been implicated in the pre- and post-implantation period. Furthermore, DNA methylation has been lately characterized as an epigenetic mark since it is one of the most important processes involved in the maintenance of genome stability. Physiological embryo development appears to depend upon the correct DNA methylation pattern. Due to the fact that soon after fertilization the zygote undergoes several morphogenetic and developmental events including activation of embryonic genome through the transition of the maternal genome, a diverse gene expression pattern may lead to clinically important conditions, such as apoptosis or the production of a chromosomically abnormal embryo. The present review focused on genes and their role during pre-implantation embryo development, giving emphasis on the various parameters that may alter gene expression or DNA methylation patterns. The pre-implantation embryos derived from in vitro culture systems (in vitro fertilization) and the possible effects on gene expression after the prolonged culture conditions are also discussed.

3.
Andrologia ; 47(3): 295-302, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24621442

RESUMO

Sperm DNA fragmentation (SDF) has been proposed to be one of the main markers regarding male infertility. A prospective study was performed to assess primarily whether sperm DNA damage has any impact on embryological data and secondarily on pregnancy rates. This prospective study evaluated the sperm DNA damage in fresh ejaculated sperm samples from couples undergoing IVF/ICSI treatments, using the improved SCD method, known as Halosperm(®) . The results were evaluated by performing statistical analysis with the statistical package of SPSS v17. A total of 156 fresh semen samples derived from 156 couples undergoing 156 IVF/ICSI cycles. From the 156 couples, 139 finally reached the embryo transfer (ET) procedure. Overall, SDF did not correlate with embryological data, while ongoing pregnancy rate/ET was 21.6%. SDF only correlated with sperm characteristics. After the categorisation of SDF (≤35% and >35%), according to the specific references of the method used, embryological data were comparable as also ongoing pregnancy rates. Using the SCD method, sperm DNA damage is associated neither with embryological data nor to pregnancy rates. However, we should not rule out the fact that extremely high DNA damages are associated with total pregnancy failure.


Assuntos
Fragmentação do DNA , Fertilização in vitro , Infertilidade Masculina/genética , Infertilidade Masculina/terapia , Espermatozoides/metabolismo , Transferência Embrionária , Feminino , Humanos , Infertilidade Masculina/metabolismo , Masculino , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas
4.
Horm Metab Res ; 46(1): 36-40, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24108390

RESUMO

The effect of ghrelin on gonadotropin secretion has been equivocal. Recent data have shown an inhibitory effect of repeated injections of ghrelin on nocturnal LH and FSH secretion in women. The aim of this study was to investigate the effect of submaximal doses of ghrelin on the diurnal secretion of gonadotropins. Ten normally cycling women received 2 consecutive dosages of ghrelin (0.15 µg/kg and 0.30 µg/kg) intravenously in the early and late follicular phases of the cycle. Saline was injected in the preceding cycle. Blood samples in relation to ghrelin or saline administration (time 0 and 90 min) were taken at -15, 0, 30, 90, 120, 150, and 180 min. Serum estradiol concentrations were significantly higher in the late than in the early follicular phase. Following ghrelin administration, serum LH and FSH levels decreased significantly, in relation to the saline injection, in the late (p<0.01), although FSH values showed a within the group decrease also in the early follicular phase (p<0.05). The study suggests a differential action of ghrelin on diurnal gonadotropin secretion throughout the follicular phase of the cycle.


Assuntos
Grelina/administração & dosagem , Grelina/farmacologia , Gonadotropinas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Hormônio Foliculoestimulante/sangue , Fase Folicular/efeitos dos fármacos , Humanos , Injeções Intravenosas , Hormônio Luteinizante/sangue
5.
Arch Gynecol Obstet ; 290(4): 777-82, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24840110

RESUMO

PURPOSE: Both cigarette smoking and alcohol consumption are somehow implicated in sperm function, but the impact of these two lifestyle factors on sperm parameters remains controversial. The present study is focused on the impact of cigarette smoking and alcohol consumption separately and combined on sperm parameters and sperm DNA fragmentation (SDF). METHODS: The study included 207 consecutive semen samples derived from men who were seeking semen analysis for fertility purposes in our IVF Unit. RESULTS: Semen volume, percent of degenerated spermatozoa and SDF were significantly correlated with the various smoking status. The percent of spermatozoa with small halos significantly correlated with the alcohol status. The smoking status of the men was correlated with the alcohol status. CONCLUSIONS: Cigarette smoking and alcohol consumption separately and combined were found to have deleterious effect on sperm parameters and SDF. It is suggested that both habits may contribute to infertility problems.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Fragmentação do DNA , Fumar/efeitos adversos , Espermatozoides/anormalidades , Adulto , Humanos , Masculino , Estudos Prospectivos , Kit de Reagentes para Diagnóstico , Contagem de Espermatozoides , Motilidade dos Espermatozoides
6.
Environ Pollut ; 350: 123967, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38631452

RESUMO

Roundup® (R), while it is the most used herbicide globally, and its residues are ubiquitous in urban and suburban areas, its impact on vertebrates' safety remains highly debated. Here, in three in vitro experiments, we investigated the effects of a very low dose (1 ppm) of R on the fertilization capacity and embryo development in cattle. In the first experiment, frozen-thawed bull semen exposed to R for 1 h exhibited reduced motility parameters but unaffected fertilization ability. However, after in vitro fertilization, the rates of embryo formation were significantly lower compared to the untreated controls. In the second experiment, oocytes exposed to R during in vitro maturation showed reduced cleavage rates, and the embryo yield on days 7, 8, and 9 of embryo culture was significantly lower than that of the controls. In the third experiment, oocytes were matured in the presence of R and in a medium containing both R and Zinc, chosen to offer antioxidant protection to the oocytes. Day-7 blastocysts were analyzed for the expression of genes associated with oxidative stress, apoptosis, and epigenetic reprogramming. Exposure to R markedly suppressed embryo formation rates compared to the controls. The combination of R with Zinc restored the blastocyst yield, which on days 8 and 9 was comparable to that of the controls and higher than the groups exposed only to R on all days. The gene expression analysis revealed that R promotes oxidative stress development, triggers apoptosis, and induces epigenetic changes in developing embryos, while zinc presence alleviates these adverse effects of R. These findings imply that even at very low doses, R could be highly toxic, leading to functional abnormalities in both gametes, potentially affecting fertility in both genders.


Assuntos
Fertilização in vitro , Glicina , Glifosato , Herbicidas , Animais , Herbicidas/toxicidade , Bovinos , Glicina/análogos & derivados , Glicina/toxicidade , Masculino , Feminino , Desenvolvimento Embrionário/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Blastocisto/efeitos dos fármacos , Células Germinativas/efeitos dos fármacos
7.
J Endocrinol Invest ; 34(4): 276-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20530986

RESUMO

BACKGROUND: Administration of ghrelin to women stimulates the secretion of PRL but the mechanism is not known. AIM: The aim of the study was to investigate the effect of the dopamine receptor blocker, metoclopramide, on ghrelin-induced PRL release. SUBJECTS AND METHODS: Ten healthy normally cycling women were studied in the midluteal phase of 4 menstrual cycles. A single dose of normal saline (cycle 1), ghrelin (1 µg/kg) (cycle 2), metoclopramide (20 mg) (cycle 3), and ghrelin plus metoclopramide (cycle 4) was given to the women iv. Blood samples in relation to the iv injection (time 0) were taken at -15, 0, 15, 30, 45, 60, 75, 90, and 120 min. The response of PRL and GH was assessed. RESULTS: Following ghrelin administration (cycles 2 and 4), plasma ghrelin and serum PRL and GH levels increased rapidly, peaking at 30 min (p<0.001). PRL was also increased after the injection of metoclopramide (p<0.001, cycle 3), but the increase was much greater than after the administration of ghrelin. The combination of ghrelin and metoclopramide stimulated PRL secretion to the same extent with metoclopramide alone. No changes in GH and PRL levels were seen after saline injection. CONCLUSIONS: These results demonstrate that the stimulating effect of ghrelin on PRL secretion is not additive with that of metoclopramide, although a dose range study might provide further information.


Assuntos
Grelina/farmacologia , Metoclopramida/farmacologia , Prolactina/metabolismo , Adulto , Antagonistas de Dopamina/farmacologia , Feminino , Grelina/sangue , Humanos , Ciclo Menstrual/sangue , Ciclo Menstrual/fisiologia , Prolactina/sangue , Radioimunoensaio , Adulto Jovem
8.
Horm Metab Res ; 42(3): 204-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19844859

RESUMO

It is known that ghrelin stimulates the secretion of prolactin in women. The aim of this study was to examine the effect of exogenous thyrotropin-releasing hormone (TRH) on ghrelin-induced prolactin release. Ten healthy normally cycling women were studied in four menstrual cycles. The women were injected intravenously in late follicular phase (follicle size 16-17 mm) with a single dose of normal saline (cycle 1), ghrelin (1 microg/kg) (cycle 2), thyrotropin-releasing hormone (200 microg) (cycle 3), and ghrelin plus thyrotropin-releasing hormone (cycle 4). Blood samples in relation to saline or drugs injection (time 0) were taken at -15, 0, 15, 30, 45, 60, 75, 90, and 120 min. The prolactin and growth hormone responses were assessed. After ghrelin administration (cycles 2 and 4), plasma ghrelin, serum prolactin, and growth hormone levels increased rapidly, peaking at 15-30 min (p<0.001). The injection of thyrotropin-releasing hormone (cycle 3) stimulated prolactin secretion markedly (p<0.001), but reduced growth hormone levels significantly (p<0.05). Ghrelin induced a smaller prolactin increase than thyrotropin-releasing hormone (p<0.05). The combination of ghrelin and thyrotropin-releasing hormone induced a similar increase in prolactin levels as with thyrotropin-releasing hormone alone. No changes in growth hormone and prolactin levels were seen after saline injection. These results demonstrate that the stimulating effect of ghrelin on prolactin secretion is not additive with that of thyrotropin-releasing hormone.


Assuntos
Grelina/farmacologia , Prolactina/metabolismo , Hormônio Liberador de Tireotropina/farmacologia , Adulto , Área Sob a Curva , Feminino , Fase Folicular/efeitos dos fármacos , Grelina/administração & dosagem , Grelina/sangue , Humanos , Prolactina/sangue , Hormônio Liberador de Tireotropina/administração & dosagem , Adulto Jovem
9.
Biomed Res Int ; 2018: 6287507, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30112409

RESUMO

Surrogacy is an assisted reproduction-based approach in which the intended parents assign the gestation and birth to another woman called the surrogate mother. The drivers of surrogacy refer largely to infertility, medical conditions, same-sex couples' parenting, and cases of diversity regarding sexual identity and orientation. Surrogacy consists of a valid option for a variety of conditions or circumstances ranging from medical to social reasons. However, surrogacy may be associated with risks during the preimplantation, prenatal, and neonatal period. It became obvious during the exhaustive literature research that data on surrogacy and its association with factors specific to the IVF practice and the options available were not fully represented. Could it be that surrogacy management adds another level of complexity to the process from the ovarian stimulation, the subsequent IVF cycle, and the techniques employed within the IVF and the Genetic Laboratory to the fetal, perinatal, and neonatal period? This work emphasizes the risks associated with surrogacy with respect to the preimplantation embryo, the fetus, and the infant. Moreover, it further calls for larger studies reporting on surrogacy and comparing the surrogate management to that of the routine IVF patient in order to avoid suboptimal management of a surrogate cycle. This is of particular importance in light of the fact that the surrogate cycle may include not only the surrogate but also the egg donor, sperm donor, and the commissioning couple or single person.


Assuntos
Infertilidade , Cuidado Pré-Natal , Mães Substitutas , Feminino , Humanos , Lactente , Parto , Gravidez , Risco
10.
Transplant Proc ; 38(9): 2905-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17112860

RESUMO

Gingival overgrowth (GO), characterized by increased cellular and extracellular matrix components in gingival tissue, is a frequent side effect of cyclosporine (CsA). In previous studies, elevated levels of transforming growth factor-beta (TGF-beta) have been detected in GO tissue, which led to the conclusion that TGF-beta plays a major part in the pathogenesis. TGF-beta activity is mediated by three receptors; TGF-beta receptor II (TGF-beta RII), the most important, has been immunohistochemically detected in GO and normal gingival tissue. The aim of this study was to clarify whether TGF-beta RII is overexpressed in CsA-induced GO. The expression of TGF-beta RII mRNA in GO tissue of patients on CsA (n = 10, 5 women, aged 42.5 +/- 14.9 years) with renal transplantation (transplant duration 3.6 +/- 0.96 years) was compared with that in healthy gingiva of control subjects (n = 10, 5 women, aged 42.5 +/- 7.6 years). Semiquantitative reverse transcribed-polymerase chain reactions (RT-PCR) were applied with glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an internal standard. TGF-beta RII mRNA was readily detected in the GO tissue of patients on CsA. The level of TGF-beta RII mRNA relative to GAPDH in GO cases was not significantly higher than the relative TGF-beta mRNA level in normal gingiva (0.60 +/- 0.16 vs 0.52 +/- 0.19; P = .575). The precise mechanism of CsA-induced GO remains uncertain. According to our results, TGF-beta RII was not upregulated in CsA-induced GO, and may have no important role in this disorder. However, the involvement of TGF-beta in the molecular pathology of GO may be mediated via TGF-beta RI or RIII.


Assuntos
Ciclosporina/efeitos adversos , Gengiva/patologia , Receptores de Fatores de Crescimento Transformadores beta/genética , Adulto , Sequência de Bases , Coroas , Primers do DNA , DNA Complementar/genética , Feminino , Gengiva/efeitos dos fármacos , Gengiva/fisiopatologia , Humanos , Imunossupressores/efeitos adversos , Transplante de Rim/imunologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Proteínas Serina-Treonina Quinases , RNA Mensageiro/genética , Receptor do Fator de Crescimento Transformador beta Tipo II , Valores de Referência
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