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1.
Mol Biol Rep ; 48(7): 5803-5808, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34302264

RESUMO

BACKGROUND: Human endogenous retroviruses (HERVs), remnants of ancestral infections, represent 8% of the human genome. HERVs are co-opted for important physiological functions during embryogenesis; however, little is known about their expression in human gametes. We evaluated the transcriptional levels of several retroviral sequences in human spermatozoa. METHODS AND RESULTS: We assessed, through a Real-Time PCR assay, the transcription levels of the pol genes of HERV-H, -K and -W families and of env genes of syncytin (Syn)1 and Syn2 in the spermatozoa from 8 normospermic subjects. The entity and distribution of their expressions were compared to values found in white blood cells (WBCs) from 16 healthy volunteers. The level of HERV transcripts was significantly lower in spermatozoa than in WBCs for HERV-H-pol, HERV-K-pol, HERV-W-pol, and Syn2.In contrast, the level of expression of Syn1 in the sperm was similar to that found in WBCs and it was significantly higher than the mRNA concentrations of other HERV genes in spermatozoa. CONCLUSIONS: Our findings show, for the first time, the presence of several retroviral mRNAs in the sperm, although in low amounts. The higher concentration of Syn1 suggests that it could play a key role in the fusion process between gametes during fertilization and, perhaps, be involved in embryo development. Further studies could clarify whether aberrant HERV expressions, in particular of Syn1, negatively affect fertilization and embryo growth and whether sperm manipulation procedures, such as cryopreservation, may potentially influence HERV transcription in the human male gamete.


Assuntos
Regulação da Expressão Gênica , Produtos do Gene env/genética , Proteínas da Gravidez/genética , Espermatozoides/metabolismo , Adolescente , Adulto , Humanos , Masculino , Adulto Jovem
2.
Front Horm Res ; 54: 58-68, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33957624

RESUMO

Modern advances in oncological treatments determined a significant improvement in survival rates for several malignancies. Nevertheless, survivorship and quality of life of cancer survivors may be negatively impaired by metabolic and endocrine side effects related to anticancer treatments, including alterations of pituitary-gonadal axis function. In fact, both medical (chemo- and radiotherapy) and surgical approaches may negatively impact on gonadal function, leading to transient or permanent hypogonadism and infertility. In view of these considerations, fertility preservation (FP) should be a primary concern in all oncological patients who may potentially achieve parenthood, irrespectively from their sex and pubertal status at treatment, and adequate counselling should be provided before undergoing gonadotoxic therapy or gonadectomy. Cryopreservation of gametes, when feasible, represents the mainstay for FP in postpubertal age, while procedures involving storage of tissue specimens or stem cells should still be considered as experimental. Given the complexity of both hormonal and psychological implications in this clinical setting, a multidisciplinary approach is advisable for optimal FP and for early diagnosis and treatment of hypogonadism.


Assuntos
Sobreviventes de Câncer , Preservação da Fertilidade , Infertilidade , Neoplasias , Criopreservação/métodos , Preservação da Fertilidade/métodos , Humanos , Infertilidade/etiologia , Infertilidade/prevenção & controle , Neoplasias/complicações , Neoplasias/terapia , Qualidade de Vida
3.
Pharmaceuticals (Basel) ; 14(3)2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33800021

RESUMO

The segmentation of the in vitro fertilization (IVF) cycle, consisting of the freezing of all embryos and the postponement of embryo transfer (ET), has become popular in recent years, with the main purpose of preventing ovarian hyperstimulation syndrome (OHSS) in patients with high response to controlled ovarian stimulation (COS). Indeed cycle segmentation (CS), especially when coupled to a GnRH-agonist trigger, was shown to reduce the incidence of OHSS in high-risk patients. However, CS increases the economic costs and the work amount for IVF laboratories. An alternative strategy is to perform a fresh ET in association with intensive luteal phase pharmacological support, able to overcome the negative effects of the GnRH-agonist trigger on the luteal phase and on endometrial receptivity. In order to compare these two strategies, we performed a retrospective, real-life cohort study including 240 non-polycystic ovarian syndrome (PCO) women with expected high responsiveness to COS (AMH >2.5 ng/mL), who received either fresh ET plus 100 IU daily human chorionic gonadotropin (hCG) as luteal support (FRESH group, n = 133), or cycle segmentation with freezing of all embryos and postponed ET (CS group, n = 107). The primary outcomes were: implantation rate (IR), live birth rate (LBR) after the first ET, and incidence of OHSS. Overall, significantly higher IR and LBR were observed in the CS group than in the FRESH group (42.9% vs. 27.8%, p < 0.05 and 32.7% vs. 19.5%, p < 0.05, respectively); the superiority of CS strategy was particularly evident when 16-19 oocytes were retrieved (LBR 42.2% vs. 9.5%, p = 0.01). Mild OHSS appeared with the same incidence in the two groups, whereas moderate and severe OHSS forms were observed only in the FRESH group (1.5% and 0.8%, respectively). In conclusion, in non-PCO women, high responders submitted to COS with the GnRH-antagonist protocol and GnRH-agonist trigger, CS strategy was associated with higher IR and LBR than the strategy including fresh ET followed by luteal phase support with a low daily hCG dose. CS appears to be advisable, especially when >15 oocytes are retrieved.

5.
J Assist Reprod Genet ; 37(5): 1163-1170, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32185595

RESUMO

OBJECTIVE: To assess whether corifollitropin-α (CFα) late-start administration (day 4) and standard administration (day 2) can obtain similar oocyte yield and live birth rate. STUDY DESIGN: A randomized controlled trial. SETTING: University Hospital IVF Unit. PATIENTS: One hundred thirteen women undergoing IVF. INTERVENTIONS: Patients distributed in three subgroups (expected poor, normal, or high responders to FSH) were randomized into two treatment arms: (a) CFα late-start: CFα on day 4 + GnRH antagonist from day 8 + (when needed) recFSH from day 11; (b) CFα standard start: CFα on day 2 + GnRH antagonist from day 6 + (when needed) recFSH from day 9. IVF or ICSI was performed as indicated. RESULTS: Considering the whole study group, the late-start regimen obtained comparable oocyte yield (8.9 ± 5.6 vs. 8.8 ± 6.2; p = n.s.), cPR/started cycle (25% vs. 31.6%, p = n.s.), and cumulative live birth rate (LBR)/ovum pickup (OPU) (29.2% vs. 37.7%, p = n.s.) than the standard regimen. The outcome of the two regimens was comparable in the two subgroups of high and normal responders. Differently, in poor responders, oocyte yield was similar, but LBR/OPU was significantly lower with late-start CFα administration that caused 40% cancellation rate due to monofollicular response. ROC curves showed that the threshold AMH levels associated with cycle cancellation were 0.6 ng/ml for late-start regimen and 0.2 ng/ml for standard regimen. CONCLUSION: CFα may be administered on either day 2 or day 4 to patients with expected high or normal response to FSH without compromising oocyte yield and/or live birth rate. Differently, late-start administration is not advisable for expected poor responders with AMH ≤ 0.6 ng/ml. TRIAL REGISTRATION: NCT03816670.


Assuntos
Hormônio Foliculoestimulante Humano/administração & dosagem , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Liberador de Gonadotropina/administração & dosagem , Síndrome de Hiperestimulação Ovariana/tratamento farmacológico , Adolescente , Adulto , Coeficiente de Natalidade , Feminino , Fertilização in vitro/tendências , Gonadotropinas/metabolismo , Humanos , Nascido Vivo/epidemiologia , Recuperação de Oócitos/métodos , Síndrome de Hiperestimulação Ovariana/patologia , Indução da Ovulação/métodos , Gravidez , Estudos Prospectivos , Adulto Jovem
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