Human Ovarian Tissue Vitrification/Warming Has Minor Effect on the Expression of Apoptosis-Related Genes

In this study, we evaluated the incidence of apoptosis at the ultrastructural levels and expression of some apoptosis-related genes in vitrified human ovarian tissue just after warming. Human ovarian tissue biopsies from 23 women after caesarean section were transported to the laboratory within 2 hours, and then they were cut into small pieces. Some pieces were vitrified and warmed and the other samples were considered as control. Apoptosis was assessed by a transmission electron microscope and also by molecular analysis of pro-apoptotic (Fas, FasL, Bax, p53, caspase8, and caspase3) and antiapoptotic (Bcl-2 and BIRC5) genem RNA levels using real-time RT-PCR before and after vitrification. No sign of apoptosis was shown ultrastructurally in vitrified samples. The level of FasL, Bcl-2, Bax, p53, and caspase3 mRNA and Bax:Bcl-2 ratio were similar in non-vitrified and vitrified groups; however, the expression of Fas and caspase8 genes was higher and BIRC5 was lower in vitrified samples compared to non-vitrified group (P<0.05). The fine structure of human vitrified ovarian tissue was well preserved; moreover, vitrification was shown to affect the expression of some apoptosis-related genes. However, additional study is needed to confirm this observation.