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Category Archives: Human Reproduction

A short exposure to polychlorinated biphenyls deregulates cellular autophagy in mammalian blastocyst in vitro

BACKGROUND

Polychlorinated biphenyls (PCBs) are common environmental contaminants that represent an important risk factor of reproductive disorders in chronically exposed human populations. However, it is not known whether a short accidental exposure of embryos to PCBs before implantation might influence their further development and whether the effect might be reversible.

METHODS AND RESULTS

To this aim, in vitro-matured sheep blastocysts were incubated with 2 or 4 µg/ml Aroclor 1254 (A1254), a mixture of 60 PCB congeners for 48h after which blastocyst proliferation and ability for outgrowth in vitro were assessed. Blastocysts exposed to A1254 showed: (i) reduced proliferation and cell number (particularly in the inner cell mass compartment); (ii) accumulation of vacuoles and lipid droplets, diffused mitochondrial damage and up-regulation of autophagy markers (ATG6 and LC3), all signs indicative of deregulated autophagy, and (iii) massive cell death. Although exposed embryos resumed growth following A1254 removal, their subsequent development remained severely perturbed.

CONCLUSIONS

These findings indicate that short exposure of blastocysts to PCBs leads to its damage characterized by deregulated autophagy and subsequent cell death.

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Vitrification at the pre-antral stage transiently alters inner mitochondrial membrane potential but proteome of in vitro grown and matured mouse oocytes appears unaffected

BACKGROUND

Vitrification is a fast and effective method to cryopreserve ovarian tissue, but it might influence mitochondrial activity and affect gene expression to cause persistent alterations in the proteome of oocytes that grow and mature following cryopreservation.

METHODS

In part one of the study, the inner mitochondrial membrane potential (mit) of JC-1 stained oocytes from control and CryoTop vitrified pre-antral follicles was analyzed by confocal microscopy at Day 0, or after culture of follicles for 1 or 12 days. In part two, proteins of in vivo grown germinal vesicle (GV) oocytes were subjected to proteome analysis by SDS polyacrylamide gel electrophoresis, tryptic in-gel digestion of gel slices, and one-dimensional-nano-liquid chromatography of peptides on a multi-dimensional-nano-liquid chromatography system followed by mass spectrometry (LC-MS/MS) and Uniprot Gene Ontology (GO) analysis. In part three, samples containing the protein amount of 40 GV and metaphase II (MII) oocytes, respectively, from control and vitrified pre-antral follicles cultured for 12 or 13 days were subjected to 2D DIGE saturation labeling and separated by isoelectric focusing and SDS gel electrophoresis (2D DIGE), followed by DeCyderTm analysis of spot patterns in three independent biological replicates. Statistical and hierarchical cluster analysis was employed to compare control and vitrified groups.

RESULTS

(i) Mitochondrial inner membrane potential differs significantly between control and vitrified GV oocytes at Day 0 and Day 1, but is similar at Day 12 of culture. (ii) LC-MS/MS analysis of SDS gel fractionated protein lysates of 988 mouse GV oocytes revealed identification of 1123 different proteins with a false discovery rate of <1%. GO analysis assigned 811 proteins to the ‘biological process’ subset. Thirty-five percent of the proteins corresponded to metabolic processes, about 15% to mitochondrion and transport, each, and close to 8% to oxidation-reduction processes. (iii) From the 2D-saturation DIGE analysis 1891 matched spots for GV-stage and 1718 for MII oocyte proteins were detected and the related protein abundances in vitrified and control oocytes were quantified. None of the spots was significantly altered in intensity, and hierarchical cluster analysis as well as histograms of p and q values suggest that vitrification at the pre-antral stage does not significantly alter the proteome of GV or MII oocytes compared with controls.

CONCLUSIONS

Vitrification appears to be associated with a significant transient increase in mit in oocyte mitochondria, which disappears when oocyte/cumulus cell apposition is restored upon development to the antral stage. The nano-LC-MS/MS analysis of low numbers of oocytes is useful to obtain information on relevant biological signaling pathways based on protein identifications. For quantitative comparisons, saturation 2D DIGE analysis is superior to LC-MS/MS due to its high sensitivity in cases where the biological material is very limited. Genetic background, age of the female, and/or stimulation protocol appear to influence the proteome pattern. However, the quantitative 2D DIGE approach provides evidence that vitrification does not affect the oocyte proteome after recovery from transient loss of cell–cell interactions, in vitro growth and in vitro maturation under tested conditions. Therefore, transient changes in mitochondrial activity by vitrification do not appear causal to persistent alterations in the mitochondrial or overall oocyte proteome.

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Effect of cryopreservation and transplantation on the expression of kit ligand and anti-Mullerian hormone in human ovarian tissue

BACKGROUND

Although cryopreservation and transplantation of ovarian tissue represent a promising alternative to safeguard fertility in cancer patients, low recovery rates of oocytes aspirated from antral follicles and a significant number of empty follicles have been observed in women with transplanted frozen–thawed ovarian tissue. In order to understand how freezing and/or grafting may affect follicular development, the follicular expression of kit ligand (KL) and anti-Müllerian hormone (AMH), two key factors activating and inhibiting follicle growth, were assessed after long-term grafting in severe combined immunodeficient (SCID) mice.

METHODS

Ovarian biopsies from eight patients were used for fresh and frozen–thawed tissue xenografting in 13 SCID mice for a period of 28 weeks, including 2 weeks of gonadotrophin stimulation. KL, AMH and proliferating cell nuclear antigen (PCNA) immunostaining were quantified before and after grafting in the two treatment groups (fresh and frozen–thawed grafted ovarian tissue).

RESULTS

Lower expression of KL was found in primordial and primary follicles after grafting of both fresh and frozen–thawed tissue. Consistent expression of AMH was found in most growing follicles at a similar rate in both graft types. In fresh and frozen–thawed grafts, 13–14% of primordial follicles were PCNA-positive, indicating a similar maintenance of quiescent follicles despite follicle activation.

CONCLUSIONS

Grafting and/or gonadotrophin stimulation appear to affect the follicular expression of KL, which may alter oocyte quality. AMH expression in growing follicles after ovarian tissue transplantation may be one of the factors contributing to the preservation of resting follicles in 28-week-old grafts.

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Australian perspectives on surrogacy: the influence of cognitions, psychological and demographic characteristics

BACKGROUND

The aim of the present study was to explore current Australian support levels for surrogacy treatments and also whether this support differed between traditional surrogacy and gestational surrogacy. The focus was also on understanding the underlying influences on surrogacy attitudes. It was hypothesized that cognitions, psychological and demographic characteristics would all predict attitudes to surrogacy and that cognitive concerns about surrogacy would be the strongest predictor.

METHODS

Participants (N = 195: 79 male, 116 female; age range 18–76 years) were first-year psychology undergraduates (47%) and friends and associates of the authors (53%). They completed a survey pack which assessed attitudes and knowledge about surrogacy, as well as empathy and other personality characteristics.

RESULTS

The results indicated that there has been a marked increase in support for surrogacy treatment in recent years, with nearly 80% of participants supporting surrogacy, and that support for gestational surrogacy was greater than that for traditional surrogacy (P< 0.001). As anticipated, cognitive concerns about surrogacy were the strongest predictors of surrogacy attitudes (R2= 0.393).

CONCLUSIONS

A limitation of the present study was the use of a non-representative, self-selected sample that tended to be well educated and perhaps liberal minded. Despite this, given the high levels of support, it could be concluded that the recent, more permissive legislative changes, which were finalized in 2010, are reflective of the values of Australian society.

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Understanding the perceptions of and emotional barriers to infertility treatment: a survey in four European countries

BACKGROUND

Infertility can significantly impact women's lives and personal relationships. Despite the negative impact of infertility, a significant number of women who are struggling to conceive do not consult a physician. This cross-sectional survey was conducted to determine the emotional impact of infertility on women to identify which aspects of fertility treatment contribute to the psychological stress experienced by so many patients and to identify barriers to seeking treatment.

METHODS

Women (n = 445; 18–44 years) who had received fertility treatment within the past 2 years or were having trouble conceiving but had not received treatment, completed a 15-min survey online.

RESULTS

Participants were from France (n = 108), Germany (n = 111), Italy (n = 112) and Spain (n = 114). Responses indicated that infertility causes a range of emotions and can strain relationships. Women who had received treatment were more likely to feel hopeful (26 versus 21%) and closer to their partner than women not in treatment (33 versus 19%, P < 0.05). Most women delayed starting treatment because of a desire to conceive naturally, and on the advice of physicians. Women aged ≥35 years took longer to seek help with their fertility issues. Injection-related anxiety was the second greatest barrier to treatment.

CONCLUSIONS

This study has provided insight into the physical and psychological challenges of infertility treatments and permitted a better understanding of the factors that impact patient lives. A treatment protocol with minimal injections and provision of additional information may lessen the emotional impact and challenges of infertility and contribute to patient satisfaction with fertility treatment protocols.

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Antral follicle responsiveness to follicle-stimulating hormone administration assessed by the Follicular Output RaTe (FORT) may predict in vitro fertilization-embryo transfer outcome

BACKGROUND

Looking for a qualitative marker of ovarian function, we aimed to verify whether responsiveness of antral follicles to FSH administration, as reflected by the Follicular Output RaTe (FORT), is related to their reproductive competence.

METHODS

We studied 322 IVF-ET candidates aged 25–43 years who underwent controlled ovarian hyperstimulation with similar initial FSH doses. Antral follicle (3–8 mm) count (AFC) and pre-ovulatory follicle (16–22 mm) count (PFC) were performed, respectively, at the achievement of pituitary suppression (before FSH treatment) and on the day of hCG administration. The FORT was calculated by PFC x 100/AFC. FORT groups were set according to tercile values: low (<42%; n= 102), average (42–58%; n= 123) and high (>58%; n= 97).

RESULTS

The average FORT was 50.6% (range, 16.7–100.0%). Clinical pregnancy rates per oocyte retrieval increased progressively from the low to the high FORT groups (33.3, 51.2 and 55.7%, respectively, P< 0.003) and such a relationship assessed by logistic regression was independent of the confounding covariates, women's ages, AFC and PFC.

CONCLUSIONS

The observed relationship between IVF-ET outcome and the percentage of antral follicles that effectively respond to FSH administration reaching pre-ovulatory maturation suggests that FORT may be a qualitative reflector of ovarian follicular competence. Further studies with broader inclusion criteria and more personalized protocols are needed to validate these results.

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