Effect of endotoxin-induced reactive oxygen species on sperm motility

Objective: To define the mechanism of infection-induced damage of sperm. Design: The effect of lipopolysaccharide (LPS)-induced reactive oxygen species (ROS) on sperm motility and its modification by scavengers were investigated. Setting: Research laboratory of a university hospital. Patient(s): Normozoospermic semen samples were obtained from 37 healthy volunteers. Intervention(s): The sperms were incubated in the presence of LPS with or without scavengers. Main Outcome Measure(s): Sperm motility was evaluated by a sperm quality analyzer (SQAIIB). ROS formation in semen samples was measured by a Berthold luminometer (LB953). Result(s): Motility of spermatozoa was decreased in the LPS-treated samples compared with that in the control groups. ROS was significantly higher in the LPS-treated groups than in the control groups. The addition of ROS scavengers restored the motility index and suppressed ROS production in the LPS-treated semen samples. Conclusion(s): These data suggest that endotoxin-induced excessive production of ROS is responsible for the decrease in sperm motility and that antioxidant therapy may be a therapeutic option for infertile men with bacterial genital tract infection.