AIMTo examine the relationship between sperm DNA damage and sperm nuclear histone (H2B) staining.

METHODSWe evaluated sperm samples from 14 consecutive asthenoteratozoospermic infertile men and six consecutive fertile controls. Sperm nuclear histone (H2B) staining and sperm chromatin integrity (assessed by sperm chromatin structure assay and expressed using the percentage of (i) DNA fragmentation index [% DFI] and (ii) high DNA stainability [% HDS)]) were evaluated.

RESULTSHistone H2B immunocytochemistry demonstrated two nuclear staining patterns: (i) focal punctate staining; and (ii) diffuse staining. Infertile men had a higher mean percentage of spermatozoa exhibiting diffuse H2B staining than did fertile men (7.7% +/- 4.6% vs. 1.6% +/- 1.2%, respectively, P < 0.01). We observed significant relationships between the proportion of spermatozoa with diffuse nuclear histone staining and both sperm % DFI (r = 0.63, P < 0.01) and sperm %HDS (r = 0.63, P < 0.01).

CONCLUSIONThe data demonstrate that infertile men have a higher proportion of spermatozoa with diffuse histone H2B than do fertile men and suggest that sperm DNA damage might, at least in part, be due to abnormally high histone H2B levels.

Adult ; Chromatin ; chemistry ; metabolism ; DNA ; biosynthesis ; DNA Fragmentation ; Histones ; metabolism ; Humans ; Immunohistochemistry ; Infertility, Male ; metabolism ; Male ; Nucleic Acid Denaturation ; Sperm Motility ; physiology ; Spermatozoa ; metabolism

Purpose: Seminal oxidative stress (OS) is a recognized factor potentially associated with male infertility, but the efficacy of antioxidant (AOX) therapy is controversial and there is no consensus on its utility. Primary outcomes of this study were to investigate the effect of AOX on spontaneous clinical pregnancy, live birth and miscarriage rates in male infertile patients. Secondary outcomes were conventional semen parameters, sperm DNA fragmentation (SDF) and seminal OS. Materials and Methods: Literature search was performed using Scopus, PubMed, Ovid, Embase, and Cochrane databases.Only randomized controlled trials (RCTs) were included and the meta-analysis was conducted according to PRISMA guidelines. Results: We assessed for eligibility 1,307 abstracts, and 45 RCTs were finally included, for a total of 4,332 infertile patients.We found a significantly higher pregnancy rate in patients treated with AOX compared to placebo-treated or untreated controls, without significant inter-study heterogeneity. No effects on live-birth or miscarriage rates were observed in four studies.A significantly higher sperm concentration, sperm progressive motility, sperm total motility, and normal sperm morphology was found in patients compared to controls. We found no effect on SDF in analysis of three eligible studies. Seminal levels of total antioxidant capacity were significantly higher, while seminal malondialdehyde acid was significantly lower in patients than controls. These results did not change after exclusion of studies performed following varicocele repair. Conclusions The present analysis upgrades the level of evidence favoring a recommendation for using AOX in male infertility to improve the spontaneous pregnancy rate and the conventional sperm parameters. The failure to demonstrate an increase in live-birth rate, despite an increase in pregnancy rates, is due to the very few RCTs specifically assessing the impact of AOX on live-birth rate. Therefore, further RCTs assessing the impact of AOX on live-birth rate and miscarriage rate, and SDF will be helpful.

Purpose: Varicoceles can be a source of elevated seminal oxidative stress (OS) and sperm DNA fragmentation (SDF). However, it remains unclear whether varicocele repair (VR) could reduce these parameters. This systematic review and meta-analysis (SRMA) aims to investigate the impact of VR on SDF and seminal malondialdehyde (MDA). Materials and Methods: A literature search was performed in Scopus, PubMed, Ovid, Embase, and Cochrane databases. This SRMA included randomized controlled trials and observational studies reporting the pre- and postoperative levels of SDF and seminal OS in infertile men with clinical varicocele that underwent VR. Subgroup analyses included techniques of VR and SDF testing. The effect size was expressed as standardized mean difference (SMD). Results: Out of 1,632 abstracts assessed for eligibility, 29 studies with 1,491 infertile men were included. The analysis showed a significant reduction in SDF after VR, compared to preoperative values (SMD −1.125, 95% confidence interval [CI] −1.410, −0.840; p<0.0001) with high inter-study heterogeneity (I2=90.965%). Reduction in SDF was evident with microsurgical technique and non-microsurgical inguinal approaches (SMD −1.014, 95% CI −1.263, −0.765; p<0.0001, and SMD −1.495, 95% CI −2.116, −0.873; p<0.0001), respectively. Reduction in SDF was significant irrespective of testing was done by sperm chromatin dispersion (SMD −2.197, 95% CI −3.187, −1.207; p<0.0001), sperm chromatin structure assay (SMD −0.857, 95% CI −1.156, −0.559; p<0.0001) or TUNEL (SMD −1.599, 95% CI −2.478, −0.719; p<0.0001). A significant decrease in seminal MDA levels was observed following VR (SMD −2.450, 95% CI −3.903 to −0.997, p=0.001) with high inter-study heterogeneity (I2=93.7%). Conclusions Using pre- and post-intervention data, this SRMA indicates a significant reduction in SDF and seminal MDA levels in infertile men with clinical varicocele treated with VR. These findings may have important implications for the future management of this selected group of infertile patients.

Humans ; Semen ; Semen Analysis ; Sperm Motility ; World Health Organization

Purpose: Despite the significant role of varicocele in the pathogenesis of male infertility, the impact of varicocele repair (VR) on conventional semen parameters remains controversial. Only a few systematic reviews and meta-analyses (SRMAs) have evaluated the impact of VR on sperm concentration, total motility, and progressive motility, mostly using a before-after analytic approach. No SRMA to date has evaluated the change in conventional semen parameters after VR compared to untreated controls. This study aimed to evaluate the effect of VR on conventional semen parameters in infertile patients with clinical varicocele compared to untreated controls. Materials and Methods: A literature search was performed using Scopus, PubMed, Embase, and Cochrane databases following the Population Intervention Comparison Outcome (PICOS) model (Population: infertile patients with clinical varicocele; Intervention: VR [any technique]; Comparison: infertile patients with clinical varicocele that were untreated; Outcome: sperm concentration, sperm total count, progressive sperm motility, total sperm motility, sperm morphology, and semen volume; Study type: randomized controlled trials and observational studies). Results: A total of 1,632 abstracts were initially assessed for eligibility. Sixteen studies were finally included with a total of 2,420 infertile men with clinical varicocele (1,424 patients treated with VR vs. 996 untreated controls). The analysis showed significantly improved post-operative semen parameters in patients compared to controls with regards to sperm concentration (standardized mean difference [SMD] 1.739; 95% CI 1.129 to 2.349; p<0.001; I2=97.6%), total sperm count (SMD 1.894; 95% CI 0.566 to 3.222; p<0.05; I2=97.8%), progressive sperm motility (SMD 3.301; 95% CI 2.164 to 4.437; p<0.01; I2=98.5%), total sperm motility (SMD 0.887; 95% CI 0.036 to 1.738; p=0.04; I2=97.3%) and normal sperm morphology (SMD 1.673; 95% CI 0.876 to 2.470; p<0.05; I2=98.5%). All the outcomes showed a high inter-study heterogeneity, but the sensitivity analysis showed that no study was sensitive enough to change these results. Publication bias was present only in the analysis of the sperm concentration and progressive motility. No significant difference was found for the semen volume (SMD 0.313; 95% CI -0.242 to 0.868; I2=89.7%). Conclusions This study provides a high level of evidence in favor of a positive effect of VR to improve conventional semen parameters in infertile men with clinical varicocele. To the best of our knowledge, this is the first SRMA to compare changes in conventional semen parameters after VR with changes in parameters of a control group over the same period. This is in contrast to other SRMAs which have compared semen parameters before and after VR, without reference to a control group. Our findings strengthen the available evidence and have a potential to upgrade professional societies’ practice recommendations favoring VR to improve conventional semen parameters in infertile men.