Effect of selenium on freezing-thawing damage of mice spermatogonial stem cell: a model to preserve fertility in childhood cancers.

Background: During treatment of childhood cancers, fertility of boys may be affected. Therefore, freezing spermatogonial stem cell (SSC) is recommended. However, freezing-thawing process may cause damage to SSCs. This study was conducted to evaluate protective effects of selenium on freezing-thawing damage of mice SSCs using investigation of cell viability and investigation of apoptosis related genes expression including Fas, Caspase3, Bcl2, Bax and P53.

Methods: SSCs were extracted from 80 6-day-old mice. The SSCs were divided into four groups: cryopreservation along with selenium (low and high dose), vitrification along with selenium (low and high dose), cryopreservation control, and vitrification control. Trypan blue staining and real-time polymerase chain reaction (real-time PCR) were used to investigate cell viability and gene expression, respectively.

Result: Comparison of cell viability in the experimental groups did not show a significant association. Expression of Fas and Caspase3 was significantly lower in cryopreservation group with low-dose selenium. Expression of Bcl2 was significantly lower in cryopreservation group with high-dose selenium. Expression of Bax and Caspase3 was significantly lower in vitrification group with low-dose selenium, and expression of P53 was significantly upper. Expression of Bax and Fas was significantly lower in vitrification group with high-dose selenium, and expression of P53 was significantly upper (P<0.001).

Conclusions: Selenium had dose dependent effect on apoptosis related genes profile. The only evident effect was the effect of low-dose selenium in cryopreservation on inhibition of apoptosis via extrinsic pathway.