Cell membrane proteins from oviductal epithelial cell line protect human spermatozoa from oxidative damage.

OBJECTIVE: To study the potential protective action in vitro of oviductal epithelial cell membrane proteins against oxidative damage in human spermatozoa. DESIGN: Prospective in vitro study. SETTING: University research laboratory and infertility clinic. PATIENT(S): Semen from men attending the infertility clinic at the Queen Mary Hospital with normal semen parameters (World Health Organization, 2010). INTERVENTION(S): We studied the effect of oviductal epithelial cell membrane proteins on the sperm functions and endogenous antioxidant enzyme activities. MAIN OUTCOME MEASURE(S): Sperm motility, lipid peroxidation, DNA fragmentation, intracellular reactive oxygen species (ROS) level, superoxide dismutase, and glutathione peroxidase activities. RESULT(S): Oviductal epithelial cell membrane proteins bind to the human spermatozoa and protect them from ROS-induced damages in terms of sperm motility, membrane integrity, DNA integrity, and intracellular ROS level. Spermatozoa-oviduct epithelial cell interaction also enhances the antioxidant defenses in spermatozoa. CONCLUSION(S): Our results demonstrated the protective effects of spermatozoon-oviductal epithelial cell interaction against oxidative stress in human spermatozoa. The results enhance our understanding of the protective mechanism of oviduct on sperm functions.