P-117: Gene Expression and Developmental State of Mouse Cloned Embryos after Treatment with Histone Deacetylase Inhibitor,Suberoylanilide Hydroxamic Acid (SAHA)

Background: It is known that acetylation level of the nuclear histones in cloned embryos is lower compare to normally developed embryos. Histone deacetylas inhibitors (HDACi) with improvement of acetylation level in these embryos can affect embryo quality in pre-implantation stage and expression level of different genes especially developmental genes. Materials and Methods: In this research, SAHA as an HDACi is used for cloned embryo treatment. These embryos treated with 5μM SAHA after beginning activation during 10 hours. Then development to blastocyst stage, total cells count(Tukey HSD test) and rate of cells undergo apoptosis (with TUNEL test) were measured(Dunnett T3 test) and expression level of Oct4, Cdx2, Hspc117, Nanog and Igf2 genes were studied with Real Time PCR method(Mann-Whitney test). Results: The average of total cells number of the treated cloned embryos to the blastocyst stage compared with untreated group were increased (p≤0.05), and also cells that had undergone apoptosis were reduced statistically (p<0.05). Expression level of specified genes in cloned untreated embryos showed significant reduction compared with natural produced embryos. However SAHA treatment resulted increasing of genes expression (p<0.05). Pre-implantation development to blastocyst stage in treated group showed non-significantly enhancement compared with untreated group. Conclusion: Although, the SAHA did not cause the enhancement of pre-implantation development to the blastocyst stage, the numbers of cells were increased and apoptosis were decreased. So the quality of blastocyst obtained from cloning procedure improved. Increasing expression of the mentioned genes especially Nanog and Igf2 to normal level of natural produced embryo maybe improves developmental potential and survival rate of embryos in post-implantation stages.