Effects of genistein supplementation on the characteristics of human sperm during liquid storage.

Cryopreservation, the most popular way to preserve human sperm, led to a significant decline in sperm motility. Here, we tried to introduce a new method to store sperm without freezing. Different concentrations of genistein were added to liquid preserved sperm. We investigated the effects of supplementation on sperm total antioxidative capacity (T-AOC), glutathione(GSH), methane dicarboxylic aldehyde (MDA), acrosomal enzyme activity, and fertilization ability of sperm. The effects of liquid storage and cryopreservation on sperm parameters were also compared. IVF medium supplemented with genistein (20µmol L-1) maintained sperm motility for up to 11 days. The addition of genistein led to a decrease in reactive oxygen species (ROS) generation that demonstrated an effective improvement in sperm motility and decreased the MDA production and maintained the GSH content and enhanced the oxidative stress resistance ability of the sperm during liquid storage. The storage sperm were used for intracytoplasmic sperm injection(ICSI) into human oocytes and activated oocytes successfully. Sperm stored in liquid medium containing genistein was superior to sperm stored in liquid nitrogen in terms of antioxidant stress and fertilization ability. We confirmed that genistein could be used as an antioxidant for the liquid storage of sperm. Sperm stored in an IVF medium with genistein could avoid cryodamage, which may become an alternative option in assisted reproduction technology.