Improvement of porcine SCNT embryo development using histone deacetylase inhibitors

Somatic cell nuclear transfer (SCNT) has been used in crucial and potential fields of the animal reproduction. Despite the successful birth of cloned animals, the cloning efficiency of SCNT has been still low. Abnormal epigenetic reprogramming has been reported as the cause of the low efficiency of SCNT in cloned embryos. Here, the study aimed to improve the developmental competence of porcine SCNT embryos using Trichostatin A (TSA) and Scriptaid which are well known as histone deacetylase inhibitors that would enhance epigenetic reprograming in cloned embryos by suppressing the event of histone deacetylation. Moreover, this study tested whether Scriptaid would be a substitute for TSA because it has been suggested that TSA is involved in malformation of cloned embryos. Various concentrations of Scriptaid were tested and 500 nM Scriptaid treatment resulted in a significant improvement of the cloned embryo during development regarding the blastocyst formation rates. When cloned embryos were treated with 50 nM TSA or/and 500 nM Scriptaid for 15 h or 24 h, the blastocyst rates of reconstructed embryos were increased in comparison to the untreated control group. However, there was no dose-dependent difference among groups. When donor cells were treated vwth 50 nM TSA or/and 500 nM Scriptaid for 4 h the blastocyst rates of reconstructed embryos were increased in comparison with the untreated control group. Moreover the expression levels of histone deacetylase 1 (HDAC1) and histone deacetylase 2 (HDAC2) were decreased with TSA and/or Scriptaid treatment. In conclusion, TSA and/or Scriptaid treatments sigiuficantly increased the developmental competence of porcine SCNT embiyos. In addition, Scriptaid improved the development of SCNT embryos regardless of the TSA treatment. Therefore, Scriptaid would be an alternative additive to improve the development competence of cloned embryos after SCNT.