Sonia Brahem

The aim of this study was to determine if a relationship exists between the levels of sperm DNA fragmentation and necrospermia in infertile men. Semen samples obtained from 70 men consulting for infertility evaluation were analyzed according to World Health Organization (WHO) guidelines. Patients were subdivided into three groups according to the percentage of necrotic spermatozoa: normozoospermia (80%; n = 20). DNA fragmentation was detected by the terminal desoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick-end labeling (TUNEL) assay. The sperm DNA fragmentation index (DFI) was 9.28 ± 2.98% in patients with a normal level of necrotic spermatozoa, 20.25 ± 3.21% in patients with moderate necrozoospermia, and 35.31 ± 5.25% in patients with severe necrozoospermia. There was a statistically significant increase of DNA fragmentation in the necrozoospermic group (P < 0.01). A strong correlation was found between the degree of necrozoospermia and sperm DNA fragmentation. We concluded that patients with necrozoospermia showed a high level of DNA fragmentation compared to normozoospermic men. Severe necrozoospermia (>80%) is a predictive factor for increased sperm DNA damage.

The aim of this study was to evaluate the efficacy of the PureSperm density gradient centrifugation on the selecting sperm with less chromosomal aneuploidy. Semen samples were obtained from 30 infertile men with teratozoospermia and 15 fertile men with normal semen parameters. The frequencies of numerical chromosomes aberrations were simultaneously identified in neat semen and in the different fractions of the density gradient centrifugation from the same samples. Using a triple colour FISH, we show that patients with severe teratozoospermia have a significantly increased frequency of chromosomal abnormalities in their neat semen compared with normozoospermic men (P < 0.001). The mean sperm motility and sperm morphology were improved significantly after semen processing with three layers PureSperm gradient compared with whole semen (P < 0.001). In addition, aneuploidy frequencies were lower in specimens enriched by the gradient centrifugation compared with unprocessed semen. Significant differences were observed in the disomy rates for the autosome and for either sex chromosome between the neat semen and the different PureSperm fractions (P < 0.001). In conclusion, our study shows that semen processing by density gradient centrifugation is very efficient in reducing sperm with aneuploidy and diploidy.

Purpose To evaluate the frequency of sperm nuclei disomy for chromosomes 8, X, and Y in patients with severe non-obstructive oligozoospermia and to assess possible correlations between sperm nuclei aneuploidy and semen parameters or a particular clinical phenotype. Materials and methods The sperm aneuploidy rate for chromosomes X, Y, and 8 were assessed in 16 infertile men with severe non-obstructive oligozoospermia and 7 healthy men with normal semen parameters. The frequency of sperm aneuploidy was compared between several patients groups according to their clinical and biological factors. Results The total rate of chromosomally abnormal spermatozoa was significantly higher in patients with severe oligozoospermia compared to control group (P < 0.001). A significant relationship was found between the age of patients, sperm concentration, and morphology and the mean rate of sex chromosomes disomy. In addition to the low sperm count (6/ml), an elevated FSH level and an exposed to an elevated temperature are two major predictive factors leading to the production of higher numbers of chromosomally abnormal gametes. Conclusion Patients with severe oligozoospermia, who are potential candidates for assisted reproduction technology, presented a high level of sex numerical chromosome abnormalities, and consequently are at high risk of chromosome abnormalities in their offspring.

The aim of this study was to analyse the meiotic segregation and DNA fragmentation rates in ejaculated spermatozoa of Tunisian men who presented the macrocephalic sperm head syndrome and to compare the results with those from 20 fertile men with normal semen profiles. Sperm DNA fragmentation was evaluated by the terminal desoxynucleotidyl transferase–mediated deoxyuridine triphosphate biotin nick-end labelling assay. Fluorescence in situ hybridisation for chromosomes X, Y and 18 was performed for the study of meiotic segregation. Despite a normal blood karyotype, patients with large-headed spermatozoa showed a significantly higher incidence of sperm chromosomal abnormalities compared with the control group. For all the patients, tetraploidy, triploidy and diploidy were the most observed abnormalities. A very high level of DNA fragmentation was shown for these patients. In conclusion, our results demonstrated that patients with large-headed, multiple-tailed spermatozoa had significantly higher incidence of sperm chromosomal abnormalities and very high level of DNA fragmentation. So intracytoplasmic sperm injection should not be recommended to these patients, not only because of its low chances of success rate but also because of its high genetic risk.

Purpose To investigate the effects of male aging on semen quality, DNA fragmentation and chromosomal abnormalities in the spermatozoa of infertile patients and fertile men. Methods Semen samples of 140 infertile patients (24–76 years) and 50 men with proven fertility (25–65 years) were analyzed according to WHO guidelines. DNA fragmentation was detected by TUNEL assay, while aneuploidy was assessed by FISH. Results In the patient group, semen volume and vitality of spermatozoa decreased significantly with age, while sperm concentration showed a statistically significant increase with age. DNA fragmentation as well as disomy of sex chromosomes and disomy 8 did not show a statistically significant change with age. However, the diploidy rate was significantly increased with patient’s age. In the control group, conventional semen parameters as well as DNA fragmentation and chromosomal abnormalities did not show a statistically significant with age. Conclusion Increased age in infertile men is associated with an increase in sperm concentration and diploidy, as well as a decline in semen volume and sperm vitality. However motility, morphology and DNA fragmentation are not affected by male age.

The objective of this study was to determine the effects of density gradient centrifugation on sperm cell DNA integrity and to correlate any detected DNA damage with semen analysis parameter. A total of 40 semen samples were collected from nonazoospermic men presenting for infertility evaluation at our department. Individual samples were divided into two parts: one part of the semen was washed and the remainder was prepared using the PureSperm density gradient centrifugation. Sperm DNA fragmentation as evaluated by the terminal desoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick-end labelling assay, was monitored in the initially washed sample and in the different layers of the density gradient centrifugation. No significant correlations were observed between sperm DNA fragmentation, age of patient, concentration and motility. However, a significant correlation existed with strict spermatic morphology. Following density gradient centrifugation, the proportion of spermatozoa with DNA fragmentation decreased significantly when compared with whole semen. In addition, we found that spermatozoa isolated in the 90% layer possessed a significantly lower percentage of DNA damage when compared with those remaining in the 70% and 50% layers. These results demonstrate that semen processing by the PureSperm gradient is useful in selecting sperm with higher double-strand DNA integrity.