Scrotal heat stress causes sperm chromatin damage and cysteinyl aspartate-spicific proteinases 3 changes in fertile men.

PURPOSE: To observe changes in semen parameters, sperm DNA integrity, chromatin condensation and cysteinyl aspartate-spicific proteinases (Caspase-3) in adult healthy men after scrotal heat stress (SHS). METHODS: The scrotums of 19 healthy male volunteers were exposed to the condition of 40-43 °C SHS belt warming 40 min each day for successive 2 days per week. The course of SHS was continuously 3 months. Routine semen analysis, hypo-osmotic swelling (HOS) test, eosin Y (EY) staining sperm HOS and chromatin dispersion (HOS/SCD) test, HOS and aniline blue (HOS/AB) staining test were carried out before, during and after SHS. The activated Caspase 3 levels of spermatozoa were determined with a microtiter plate reader. RESULTS: The mean parameters of sperm concentration, motility and normal morphological sperm were significantly decreased in groups with sperm being collected during SHS 1, 2 and 3 months when compared with those in groups of pre-SHS (P < 0.01). Statistically significant differences of sperm DNA fragmentation, normal sperm membrane and vitality, and Caspase-3 activity were observed between the groups of before SHS and after SHS 3 months and the groups of during SHS 1, 2 and 3 months (P < 0.001). Three months the SHS stopped, various parameters recovered to the level before SHS. Abnormal sperm with HOS/AB and HOS/SCD showed a negatively significant correlation with normal sperm by HOS/EY test, and WBC in semen showed a positively significant correlation with Caspase-3 activity. The percentage of abnormal sperm by using the test of HOS/SCD showed a positively significant correlation with that of HOS/AB. CONCLUSIONS: The continuously constant SHS can impact the semen quality, sperm DNA integrity, chromatin condensation and Caspase-3, and the combination of HOS plus AB test may simultaneously determine the integrity of membrane and chromatin condensation at the same spermatozoon.

Sperm Parameters, ASAs and Apoptosis After Processing by the Double Tube and Swim up Methods.

The aim of this study was to improve the quality of semen samples by using a novel double-tube (DT) method. The DT method was developed to select sperm and compared with traditional swim-up (SU) technique for 31 semen samples. Sperm DNA integrity were tested with TUNEL and SCSA. Content of antisperm antibodies (ASA) in the semen was measured by ELISA and MAR. Levels of the caspase-3 in the sperm were assessed by western blotting. After SU and DT, 15 couples and 16 couples were underwent IVF-ET. The number of RCDs, the percentage of SDF and DFI, ASA and the level of caspase-3 were significantly decreased after DT and SU (p = .001 and p< .001). When the DT and SU compared, there were significant changes in the number of RCD, the percentage of SDF and DFI, ASA and the level of caspase-3 (p< 0.05-0.001). There was a higher cleavage rate (p = .017) and a lower abortion rate (p< .05) in DT-IVF group than in SU-IVF group. DT selection yielded spermatozoa with low RCDs, DFI, ASA, and caspase-3 which would be benefit for ART.

Changes in Levels of Seminal Nitric Oxide Synthase, Macrophage Migration Inhibitory Factor, Sperm DNA Integrity and Caspase-3 in Fertile Men after Scrotal Heat Stress.

BACKGROUND: This study observes changes in levels of seminal nitric oxide (NO), nitric oxide synthase (NOS), macrophage migration inhibitory factor (MIF), sperm DNA integrity, chromatin condensation and Caspase-3in adult healthy men after scrotal heat stress (SHS). METHODS: Exposure of the scrotum of 25 healthy male volunteers locally at 40-43°C SHS belt warming 40 min each day for successive 2 d per week. The course of SHS was continuously 3 months. Routine semen analysis, hypo-osmotic swelling (HOS) test, Aniline blue (AB) staining, HOS/AB and terminal deoxynucleotidyl transferase-mediated d UDP nick-end labeling (TUNEL) were carried out before, during and after SHS. Seminal NO and NOS contents were determined by nitrate reduction method. The activated Caspase-3 levels of spermatozoa and MIF in seminal plasma were measured by the enzyme-linked immunosorbent assay (ELISA) method. Statistical significance between mean values was determined using statistical ANOVA tests. RESULTS: The mean parameters of sperm concentration, motile and progressive motile sperm and normal morphological sperm were significantly decreased in groups during SHS 1, 2 and 3 months compared with those in groups of pre-SHS (P<0.001). Statistically significant differences of sperm DNA fragmentation, normal sperm membrane, and Caspase-3 activity as well as the level of NO, NOS and MIF in semen were observed between the groups before SHS and after SHS 3 months and the groups during SHS 1, 2 and 3 months (P<0.001). After three months of the SHS, various parameters recovered to the level before SHS. WBC in semen showed a positively significant correlation with the levels of NO, NOS, MIF and Caspase-3 activity. The percentage of abnormal sperm by using the test of HOS showed a positively significant correlation with that of HOS/AB. CONCLUSIONS: The continuously constant SHS can impact the semen quality and sperm DNA and chromatin, which may be contributed to the high level of NO, NOS, MIF and Caspase-3 by SHS.