Ethylene oxide impairs sperm motility through dysregulation of Rab proteins.

Ethylene oxide (E.O) is an ether compound that negatively affects male reproduction, specifically by impairing sperm function. However, the molecular mechanisms underlying the E.O-induced inhibition of sperm function remain poorly understood. Therefore, this study investigated the molecular mechanisms behind E.O-induced toxic effects on sperm motility by assessing Ras-associated binding (Rab) proteins. Therefore, 31 individual Duroc semen samples were analyzed to determine the correlations between Rab protein (Rab3A, Rab5, Rab14, Rab25, Rab27A, and Rab34) levels and sperm motility after exposure to 100-μM E.O. The results showed that E.O exposure significantly reduced sperm motility and motion kinematics. Furthermore, correlation analysis revealed that, in the control group, Rab3A, Rab5, Rab14, Rab25, Rab27A, and Rab34 levels were correlated with various sperm motion parameters. In contrast, only Rab3A and Rab14 levels correlated with multiple sperm motility and kinematic parameters in the 100-μM-E.O group. These results suggest that E.O may affect sperm motion parameters via the action of Rab proteins, leading to decreased sperm motility. Consequently, these findings provide important evidence of the molecular mechanisms underlying E.O-induced toxic effects on sperm function.