Effect of Selenium on Expression of Apoptosis-Related Genes in Cryomedia of Mice Ovary after Vitrification.

Introduction: Freezing of ovarian tissue is used for preservation of fertility. The freezing-thawing process is accompanied by oxidative stress and induction of apoptosis. Apoptosis is a complex process that has been studied in animal models. The present study was aimed at investigating the effect of selenium on suppression of apoptosis during vitrification-thawing process of mice ovary via studying expression of apoptosis-related genes, and also, we aimed to design statistical models for the roles of single genes and gene-gene interactions in suppression of apoptosis.

Methods: A total of 10 right ovary samples from 10 mice were randomly divided into two groups of selenium treatment (at dose 5 g/ml sodium selenite, through adding to the media) and control group. Vitrification-thawing process was done according to the existed protocols. Real-time PCR was used for gene expression study. The apoptosis gene profile included , , , and . General linear model was applied to study single gene associations and gene-gene interactions.

Results: From the studied genes, showed a significant downregulation in the selenium group in comparison to the control group (∆∆CT = 1.96; = 0.013; relative expression (RE) = 0.28). showed a significant upregulation in the selenium group in comparison to the control group (∆∆CT = -2.49; < 0.001; RE = 3.49). No significant result was found for other genes. According to the multiple models, showed a protective single gene association (beta = -0.33; = 0.032), and ∗ interaction was significantly positive (beta = 0.19; = 0.036).

Conclusion: Addition of selenium to cryomedia of vitrification-thawing process could reduce the apoptosis induced by freezing-thawing stress in mice ovary via downregulation of and upregulation of at transcription level. Multivariable statistical models should be performed in future researches to study biological systems.