Cytokines produced by microwave-radiated Sertoli cells interfere with spermatogenesis in rat testis

Microwave radiation resulted in degeneration, apoptosis or necrosis in germ cells at different stages. The molecular mechanisms by which microwaves induce spermatogenesis disorder have not been completely understood. Sertoli cells play crucial roles in mammalian spermatogenesis. Cytokines produced by Sertoli cells play pleiotropic roles in different conditions. At physiologically low concentration, TNFα, IL-1β and IL-6 behave as survival factors; while under pathological condition, these cytokines can induce apoptosis in testis. The effects of cytokines produced by microwave-radiated Sertoli cells on spermatogenesis are poorly understood. The purpose of this study was to determine the effect of cytokines produced by microwave-radiated Sertoli cells on the germ cells. We focused the effect of TNFα, IL-1β and IL-6 on the germ cells. The results showed that TNFα, IL-1β and IL-6 were increased in Sertoli cells after exposure to microwave radiation. These up-regulated cytokines can induce apoptosis and lipid peroxidation in the membrane of germ cells. In addition, germ cell apoptosis was associated with the up-regulation of Bax/Bcl-2 and caspase-3. These results suggest that cytokines produced by microwave-radiated Sertoli cells may disrupt spermatogenesis. Our data provided novel insight into the injury mechanism of germ cells induced by microwave radiation.