SUMMARYThe purpose of this study was to evaluate the seminal 8-Isoprostane, reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), catalase, total antioxidant capacity (TAC) in subjects with different level of physical fitness. A total of 161 semen samples were obtained from three groups of healthy males, including elite athletes (23.8 ± 5.2 years, n = 56) who had regular training (4-5 days per week), recreationally active men (24.2 ± 4.9 years, n = 52) who participated in educational or recreational physical activities for 4-5 h per week and non-active men (23.9 ± 5.0 years, n = 53) who did not participate in any exercise programmes for at least 6 months prior to the study. The results showed significantly higher levels of SOD, catalase and TAC as well as lower levels of 8-Isoprostane, ROS and MDA in recreationally active men compared with either elite athletes or non-active men (p < 0.001). Also, elite athletes revealed significantly higher seminal 8-Isoprostane, ROS and MDA as well as lower SOD, catalase and TAC levels compared with recreationally active and non-active men (p < 0.001). In conclusion, the results of the present study indicate that there are differences in seminal oxidants and antioxidants of elite athletes, recreationally active and non-active men. These differences are more likely related to indices that favour decrement of oxidative stress-induced peroxidative damage in spermatozoa from recreationally active men. Hence, recreationally active men seem to have a healthier semen production. The physiological significance of this observation is worthy of further investigation.

To investigate the effects of copper and superoxide dismutase (SOD) content of seminal plasma on buffalo semen characteristics, 54 semen samples collected from buffalo bulls by a bovine artificial vagina were used. Semen characteristics (motility, viability, morphology, concentration and volume) were recorded. Seminal plasma was harvested by centrifugation and kept frozen until analysis. Seminal plasma copper content was determined by atomic absorption procedure and SOD was measured by using a kit. The mean total copper value of seminal plasma was recorded as 2.51 +/- 0.04 mg kg(-1) (Mean +/- SEM) and the mean total SOD values was 39.02 +/- 0.81 IU mL(-1). To reduce the range of variability, the data were categorized according to their motility records in 3 groups of Excellent (Ex, >90% motile, n = 33), Good (Go, 80-89% motile, n = 15) and Moderate (Mo, < 79% motile, n = 6). The mean motility, viability, copper and SOD values in Ex group was recorded as 92.24 +/- 0.51%, 94.00 +/- 0.48%, 2.56 +/- 0.04 mg kg(-1) and 39.52 +/- 0.57 IU mL(-1), respectively. These values were 81.66 +/- 0.62%, 85.26 +/- 0.95%, 2.38 +/- 0.11 mg kg(-1) and 36.48 +/- 1.51 IU mL(-1) in Go group and 71.66 +/- 1.05%, 77.00 +/- 2.94%, 2.55 +/- 0.10 mg kg(-1) and 50.66 +/- 2.51 in Mo group, respectively. The mean copper value in Ex group was highly (r = 0.600) correlated with SOD and correlated with sperm motility (r = 0.372) and viability (r = 0.363), while, in Go group it was highly correlated (r = 0.945) with SOD and sperm viability (r = 0.652) and in Mo group it was correlated (r = 0.874) with semen volume only. The mean SOD values in Ex group was highly correlated with sperm motility (r = 0.492) and viability (r = 0.490) and mean copper values, in Go group, it was highly correlated whit sperm viability (r = 0.659) and mean copper values and in Mo group it had no significant correlations with semen parameters. These results suggest that copper and SOD content of the buffalo seminal plasma have an influence on the sperm motility and viability which are the most important factors in semen fertility.