Effect of scriptaid, a histone deacetylase inhibitor, on the developmental competence of Handmade cloned buffalo (Bubalus bubalis) embryos

The aim of the present study was to investigate the effect of scriptaid, a histone deacetylase inhibitor, on the developmental competence of Handmade cloned (HMC) and parthenogenetically activated (PA) buffalo embryos. Scriptaid treatment was given for 10 h immediately after reconstruction of HMC and PA embryos. Treatment of HMC embryos with 500 or 1000 nmol/L scriptaid significantly increased (P < 0.01) the cleavage rate (91.3 ± 2.8 and 91.9 ± 2.0%, respectively) than that of controls (80.7 ± 2.4%). Blastocyst rate was significantly higher (P < 0.01) following treatment with 1000 nmol/L (54.1 ± 5.0%) than that with 500 nmol/L scriptaid (42.6 ± 2.9%) which, in turn, was higher (P < 0.01) than that of the controls (38.0 ± 2.6%). Also, HMC embryos treated with 500 or 1000 nmol/L scriptaid had higher (P < 0.01) cell number (339.9 ± 1.4 and 343.4 ± 2.4, respectively) than the untreated embryos (150.7 ± 2.0). In contrast, in zona-free PA embryos, the cleavage and blastocyst rate was significantly lower (P < 0.01) following treatment with 500 (46.3 ± 1.0 and 22.0 ± 1.4%, respectively) or 1000 nmol/L scriptaid (46.2 ± 1.9 and 16.6 ± 1.3%, respectively) than that of untreated embryos (60.4 ± 3.2 and 29.5 ± 2.1%, respectively). Transfer of HMC embryos that had been untreated (N = 13) or treated with 1000 nmol/L scriptaid (N = 15) to synchronized recipients resulted in one pregnancy each. In conclusion, these results demonstrate that scriptaid treatment improves the developmental potential of HMC buffalo embryos, but compromises that of zona-free PA embryos.