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Background: One of the causes of male fertility disorders is the exposure of oxidative stress on the human sperm. Understanding the mechanism of disturbance is important to develop a better treatment for infertile or subfertile patients. Aims: The aim of this study was to analyze the effects of hydrogen peroxide (H2O2) on human sperm quality parameters and cell survival. Settings and Design: This study used an experimental design. Materials and Methods: Sperm cells from 15 donors were washed in a Percoll gradient and dissolved in Biggers, Whitter, and Whittingham medium. Cells were incubated with H2O2 at various concentrations from 0 to 250 μM for 2 h. Sperm viability was examined by eosin assay, sperm kinetic by computer‑assisted sperm analyzer, sperm penetration by cervical mucus penetration assay, and membrane integrity by hypo‑osmotic swelling test. Sperm capacitation, apoptosis, and cell survival were analyzed using western immunoblotting. Statistical Analysis Used: One‑way ANOVA on SPSS 21 combined with post hoc LSD test was used to analyze differences among the groups. A P < 0.05 was considered significant. Results: Sperm viability and kinetic were significantly reduced at H2O2 concentrations of 200 and 250 μM. H2O2 reduced sperm capability to penetrate cervical mucus and also damage cell membrane integrity at all concentrations used. H2O2 significantly inhibited sperm capacitation, indicated by reduced total tyrosine phosphorylation. H2O2 exposure stimulated activation of caspase 3 and significantly reduced phosphorylated AKT at all concentrations used. Conclusions: H2O2 comprehensively inhibits sperm qualities related to the capacity to fertilize oocyte, stimulates caspase activity, and inhibits cell survival. [ABSTRACT FROM AUTHOR]

Objective: Progesterone receptor is present in human sperm. Here, we determined if progesterone (P4) improves capacitation and stimulates sperm survival by suppressing apoptosis to evaluate its relevance to be used as a preservation agent to increase and prolong sperm viability and motility. Materials and Methods: Semen samples were obtained from healthy human donors. The sample was washed by Percoll gradient centrifugation and was divided into five groups of 500 µL, each containing approximately 10 million sperm cells. P4 was added to each group at the final concentrations of 0 (control), 250, 500, 750, and 1000 ng/mL, respectively, and was incubated at 37°C for 2 h. Sperm motility was assessed using a computer-assisted sperm analyzer. Tyrosine phosphorylation, Akt phosphorylation, and caspase-3 activation in sperm were analyzed by western immunoblotting. Results: P4 did not increase the sperm motility. Western blot analysis revealed that P4 at the concentration of 500 ng/mL increased tyrosine phosphorylation, indicating increased sperm capacitation. P4 at 750 mg/ml also increased Akt phosphorylation. Interestingly, the activation of Akt was associated with a decrease in caspase-3 activity, indicating the prosurvival effect of P4. Conclusion: This study results suggest that P4 does not influence sperm motility; however, it increases sperm tyrosine phosphorylation (at a specific concentration of 500 ng/ul), activates AKT (Protein kinase B), and suppresses caspase-3 (at a specific concentration of 750 ng/ul). The biochemical effects of P4 on sperm may warrant its use as a preservation agent to increase sperm viability. [ABSTRACT FROM AUTHOR]

Background: The etiology of unexplained infertility has not been fully understood. This study aimed to determine the effect of antisperm antibody (ASA) from infertile women on viability, motility, plasma membrane integrity, and status of tyrosine phosphorylation in the human spermatozoa. Methods: An experimental in vitro study was conducted at the Department of Biology, Faculty of Medicine, Universitas Indonesia from February to November 2014. Spermatozoa from normal fertile donors was incubated with serum containing ASA from infertile women at several dilutions (1/1000, 1/100, 1/10, and without dilution) for 1 and 2 hours. The plasma membrane integrity was assessed with hypoosmotic swelling (HOS) test, whereas the status of tyrosine phosphorylation was analyzed using Western immunoblotting and immunocytochemistry. Results: After 1 hour incubation time, ASA caused a decrease in sperm viability, motility, plasma membrane integrity, and inhibit sperm tyrosine phosphorylation. ASA caused a decrease in viability, motility, sperm plasma membrane integrity, and tyrosine phosphorylation of sperm after 1 hour incubation time. Conclusion: ASA from infertile women reduced the sperm viability, motility, plasma membrane integrity, and capacitation in dose and time dependent manner. [ABSTRACT FROM AUTHOR]

Background: Epididymal sperm maturation occurs via interactions between sperm and proteins secreted by the epididymal epithelium. Although this is an important process, the genes that encode the involved proteins remain largely uncharacterized. Previous studies have demonstrated that the genes involved in sperm maturation are regulated by androgen. Spag11a is an epididymal gene that is influenced by androgen. However, little is known about the putative role of this gene in the sperm maturation process. The objective of this study was to characterize Spag11a in the mouse epididymis. Methods: In silico analyses were performed to predict signal peptides and functional domains. Spag11a expression was measured by quantitative real-time RT-PCR. Western blots and immunocytochemistry were performed to determine protein expression. Results: SPAG11A is a member of the beta defensin protein family and constitutes a secretory protein. Spag11a was expressed exclusively in the epididymis. Moreover, it exhibited region-specific expression in the caput, which is typical for genes that are involved in creating a suitable microenvironment for sperm maturation. Mouse Spag11a was regulated by androgen. A significant decrease of Spag11a expression was observed at third day following a gonadectomy (P < 0.001). Interestingly, testosterone replacement therapy was able to maintain the expression almost at the normal level, indicating a dependency on androgen. Besides androgen, testicular factors influenced Spag11a expression in a different way. This was revealed by efferent duct ligation in which Spag11a was transiently up-regulated at the third day following the ligation before returning to the normal level at day 5. Spag11a regional expression was also observed at protein level detected by western immunoblotting which revealed a clear band in the caput but not in other regions. The prediction that SPAG11A is a secretory protein was confirmed by immunocytochemical analyses indicating cell-specific expression mainly in the caput principal cells and detection of the protein in epididymal luminal fluid and spermatozoa. Conclusions: Based on the characteristics of Spag11a, it is likely that this gene has a specific role in epididymal sperm maturation. Further studies using functional assays are necessary to confirm this finding. [ABSTRACT FROM AUTHOR]