Histone hyperacetylation may improve the preimplantation development and epigenetic status of cloned embryos.

The current study investigated the mechanism of mini pig fetal fibroblasts in improving the epigenetic modification and preimplantation development of cloned embryos. The results showed that the increased AcH3K14 level was dose- and time-dependent. Histone hyperacetylation had no significant effect on cell morphology, cell viability, cell cycle, and relative gene (HDAC1, HAT1, DNMT3A, and BAX) expression. The treated cloned embryos had significantly higher development rates and the total nuclei number than the control (27.62 ± 6.94 % vs. 16.14 ± 10.55 %; 43.90 ± 18.39 vs. 33.06 ± 15.87; P < 0.05). The AcH3K14 level in the treated cloned blastocysts was close to that of IVF blastocysts (5.17 ± 0.93 vs. 5.45 ± 1.91, P > 0.05). The gene transcription (CDX2 and OCT4) of the treated cloned blastocysts was significantly up-regulated than the control (3.32 ± 0.51 vs. 2.05 ± 0.30; 1.21 ± 0.18 vs. 0.81 ± 0.09; P < 0.05). The improvement in the cloned embryo development and the partial correction of abnormal acetylation modification were not necessarily related to the cellular characteristics. This could be caused by histone hyperacetylation of mini pig fetal fibroblasts.