The present study in sheep model was to find out the interaction of apoptotic transcripts, that is, Bcl2, Bax, Casp3, PCNA and p53 and pluripotency related transcripts, that is, Sox2, Nanog and Oct4 in ovine embryos produced in vitro at different O2 concentrations (20% and 5% O2) to compare their developmental potential. Oxygen concentrations did not influence the maturation and cleavage rate but the percentage of morula and blastocysts was significantly more at 5% as compared to 20% O2. A significant upregulated expression of Bcl2 and PCNA genes and significantly downregulated expression of Casp3 and p53 were observed in the blastocysts at 5% than those at 20% O2. The expression of Bax was not influenced by the O2 concentration. Among the pluripotency related transcripts, the expression of Oct4 was significantly upregulated and the expression of Sox2 and Nanog was significantly downregulated in embryos at 5% than at 20% O2. The study concluded that the embryos produced in vitro at low O2 (5%) concentration regulate the expression of developmental genes related to apoptosis and pluripotency to improve the developmental potential of embryos as compared to high O2 (20%) concentration.
Keywords: Embryos; apoptosis; ovine; oxygen; pluripotency.