Decrease of spermatozoa with an unbalanced chromosome content after cell sorting in men carrying a structural chromosomal abnormality

BACKGROUND

We showed that in men with a constitutional chromosomal abnormality, DNA fragmentation was significantly higher in chromosomally unbalanced spermatozoa than in spermatozoa with a normal or balanced chromosomal content. These results could be explained by a phenomenon already described in infertile men: abortive apoptosis.

OBJECTIVES

To determine whether magnetic-activated cell separation could select spermatozoa with lower levels of DNA fragmentation and unbalanced chromosome content in men carrying a structural chromosomal abnormality.

MATERIALS AND METHODS

The spermatozoa of ten males with a chromosomal rearrangement were separated into two populations using magnetic-activated cell separation (annexin V (-) and annexin V (+) fractions), in order to study meiotic segregation by fluorescence in situ hybridization, the percentage of spermatozoa with an externalization of phosphatidylserine by annexin V staining and DNA fragmentation by TdT-mediated dUTP nick-end labeling on the whole ejaculate and on selected spermatozoa in the same patient.

RESULTS

For all patients, the percentage of spermatozoa with externalization of phosphatidylserine decreased in the annexin V (-) fraction and increased in the annexin V (+) fraction as compared to the frozen-thawed semen sample. The rates of DNA fragmentation were statistically much lower in the annexin V (-) fraction when compared to the rate before magnetic-activated cell separation for all but one patient. Conversely, we observed a statistically significantly higher rate of DNA fragmentation in the annexin V (+) fraction for six patients. After magnetic-activated cell separation, there was a significant increase of normal/balanced spermatozoa in the fraction of annexin V (-) for all patients. Conversely, we observed a significant decrease in the fraction of annexin V (+) for seven patients.

DISCUSSION AND CONCLUSIONS

Magnetic-activated cell separation is a promising tool for increasing the selection of healthy spermatozoa, with a decrease in the number of spermatozoa with externalization of phosphatidylserine, DNA fragmentation, and chromosome unbalance, for use in assisted reproductive technologies such as intracytoplasmic sperm injection for males with a chromosomal structural abnormality.

[Does hyperandrogenic statute in the polycystic ovary syndrome constitute an obstacle to the success of in vitro fertilization?]

OBJECTIVES

The aim of this study was to evaluate the impact of initial androgenic statute of women with polycystic ovary syndrome (SOPK) on the expected results of in vitro fertilization (FIV).

MATERIALS AND METHODS

It is about an exploratory study carried out in 61 unfertile SOPK patients, having profited all from a cycle of FIV/ICSI (intracytoplasmic sperm injection). We have divided our population in two groups according to their hormonal androgenic statute: groups with hyperandrogenism and without hyperandrogenism. We proceeded to note the anthropometric and hormonal parameters as well as results of FIV for each of the two groups.

RESULTS

SOPK patients with hyperandrogenism are more obese than their counterparts. Also, they have more oocytes collected after ovarian induction. In addition, we did not reveal any significant differences between our two study groups concerning parameters defining FIV response.

CONCLUSION

Our findings suggest that hyperandrogenism statute in SOPK infertile women does not seem to compromise the results of FIV. On the contrary, it would make it possible to optimize the chances to puncture more significant number of oocytes.

Analyse du statut oxydatif spermatique chez des patients infertiles

Introduction

L’infertilité masculine constitue un problème de santé publique. Plusieurs facteurs sont à l’origine de ce phénomène. Actuellement, le stress oxydatif est incriminé comme l’une des principales causes. Dans notre étude, nous avons cherché une corrélation entre les marqueurs du stress oxydatif et les caractéristiques spermatiques (numération, mobilité, morphologie).

Matériel et méthodes

Nous avons évalué le statut oxydatif spermatique de 129 sujets infertiles. Ces sujets sont caractérisés par une infertilité de durée variable. Ils ont été subdivisés en quatre groupes: des sujets normozoospermiques considérés comme témoins (n=34); des asthénozoospermiques (Asthéno, n=43); des oligozoospermiques (Oligo, n=22) et tératozoospermiques (Térato, n=30). Parmi les marqueurs du stress oxydatif, nous avons évalué, dans le plasma séminal, le zinc, le calcium, le magnésium et le sélénium par spectrométrie d’absorption atomique à flamme et à four. Le malondialdéhyde (MDA) est dosé par spectrofluorométrie.

Résultats

Les résultats de notre étude montrent que les concentrations séminales du zinc et du sélénium sont plus élevées chez les normozoospermiques que les concentrations de ces mêmes éléments chez les autres groupes. La concentration séminale en zinc est significativement corrélée avec la numération spermatique (r=0,49; p<0,001) et le MDA (r=−0,35; p<0,05). La mobilité des spermatozoïdes est corrélée avec le calcium (r=0,41; p<0,001) et le magnésium (r=0,31; p<0,05). La concentration du MDA est plus élevée chez les trois groupes de patients: oligospermiques (3,22±1,37 μg/ml), asthénospermiques (3,52±1,93 μg/ml) et tératospermiques (3,64±1,73 μg/ml) par rapport aux témoins (2,32±0,94 μg/ml). Une seule corrélation positive a été observée entre le MDA et la morphologie (r=0,19; p<0,05).

Conclusion

Notre étude confirme que le stress oxydatif joue un rôle important dans le processus des altérations des spermatozoïdes. Les radicaux libres peuvent, en effet, modifier la structure membranaire ainsi que celle de l’acide désoxyribonucléique. Ces altérations conduisent aussi à une augmentation du pourcentage de spermatozoïdes de formes anormales.

[Sperm immobilizing effect of leaves extracts of Cestrum parqui]

OBJECTIVE

The leaves extracts of Cestrum parqui were reported to have spermicidal activity. The current investigation identified the spermicidal component of the extracts and evaluated its spermicidal potential in vitro, particularly the effects on sperm motility and vitality.

METHODS

Sperms were prepared by discontinuous buoyant density gradient centrifugation and incubated with varying concentrations of extract from C. parqui (40-250 μg/ml) at 37°C and 5% CO(2). The mode of spermicidal action was evaluated by sperm motility and vitality at different intervals ranging from 5 to 240 minutes. Morphological changes in human spermatozoa after exposure to the extract were evaluated under transmission electron microscope.

RESULTS

A dose- and time-dependent effect of this extract on sperm motility and viability was observed. The mean effective concentration of extracts that induced irreversible immobilization was 250 μg/ml. Transmission electron microscope revealed a significant damage to sperm membrane in head and acrosomal membranes, notable swelling and disruption.

CONCLUSION

Our study indicates that this natural extract has potential spermicidal effect in vitro. It can adequately replace nonoxynol-9 in vaginal contraceptives to make them more vaginally safe and ecofriendly.

Detection of DNA fragmentation in human spermatozoa: correlation with semen parameters

To determine the prevalence of high levels of sperm DNA damage among infertile men with normal and abnormal semen parameters, 90 patients were subdivided into the following three groups. Group A (n = 30): men with normal semen parameters who acted as the controls. Group B (n = 30): asthenozoospermic men and group C (n = 30): teratozoospermic men, suffering from male infertility. DNA damage was evaluated by the rate of DNA fragmentation index (DFI) as assessed by the terminal desoxynucleotidyl transferase-mediated dUTP nick-end labelling assay. It was found that the difference was not significant between the percentage of DFI in patients with asthenozoospermia and the normospermic men (9.46% +/- 8.68 and 8.19 +/- 6.84 respectively, P-value not significant). The patients with teratozoospermia showed a significantly higher percentage of DNA fragmentation compared with the controls (respectively 21.37 +/- 17.26% and 8.19 +/- 6.84%, P < 0.001). There was a positive correlation between abnormal sperm morphology and the DFI (r = 0.44, P < 0.01) in group C. It is concluded that the impairments of sperm parameters were associated with an increase of DNA fragmentation; this association was strictly related to atypical forms.

[DNA sperm methylation in assisted reproductive techniques]

In the last few years, many tests were developed to study the fertilizing properties of the spermatozoa. However none of them was useful to obtain a prognostic factor. Indeed, the integrity of the spermatic DNA is also necessary to a successful fertilization for obtaining a pregnancy. DNA integrity could be evaluated by the measurement of the level of DNA methylation. Indeed, in the mammals, the methylation of the ADN is involved in diverse processes amongst them the regulation of the genome expression during the embryonic development. The objective of this study is to evaluate the impact of the level of methylation of the spermatic DNA in the success of in vitro fertilization (IVF), in terms of rate of fertilization, quality of the embryos and rate of pregnancy. The immunostaining of the 5-methylecytosine, then the quantification by image analysis or with flow cytometry, allowed an objective evaluation of the level of total methylation of spermatic DNA. Our data show that the level of DNA methylation influences neither the fertilization rate nor the embryos quality. On the other hand, the rate of pregnancy is decreased if the total level of DNA methylation is lower than a threshold value. The level of spermatic DNA methylation represents a new parameter of spermatic maturation.

Hyperstimulation ovarienne induite par un agoniste de la GnRH. À propos d'un cas

We report a case of ovarian hyperstimulation induced by a GnRH agonist (Decapeptyl in a patient aged of 23 years and having 3 years of primary infertility of male origin. Twelve days after agonist administration, several ovarian follicles, great-sized, and with a rate of elevated serum oestradiol have been noted. After triggering of the ovulation by 5000 IU of HCG, oocyte retrieval permitted the collection of 4 oocytes 3 of which were mature. Only one embryo with 4 cells has been transferred 48 hours after intracytoplasmic sperm injection fertilization (ICSI), but there was no pregnancy. Ovarian hyperstimulation induced by GnRH agonist is a rare event and only a few cases have been reported. The development of multiple follicles after the administration of an agonist is a paradoxal answer of the ovary to the pituitary desensitization without a clarified physiopathology. The hypothesis of a direct action of the agonist on the ovary is likeliest. Triggering of ovulation by human chorionic gonadotrophin (HCG) has been achieved by certain authors. Fertilization of oocytes and transfers of embryos have succeeded in certain cases, but only one pregnancy has been reported that led to a living birth.