Embryotrophic effects of ethylenediaminetetraacetic acid and hemoglobin on in vitro porcine embryos development

This study investigated the embryotrophic effects of ethylenediaminetetraacetic acid (EDTA) and hemoglobin (Hb) on porcine preimplantation embryo development. Porcine embryos produced by in vitro maturation/fertilization were cultured for 6 days in modified North Carolina State University-23 medium (mNCSU-23) supplemented with EDTA and/or Hb. In Exp. 1, culturing porcine zygotes with 100 μM EDTA significantly increased cleavage frequencies (85.3%) at 48 h post insemination and the number of inner cell mass (ICM) (9.6 ± 5.5) compared to the control (7.0 ± 2.8). However, 100 μM EDTA did not improve blastocyst formation compared to 0, 1 or 10 μM EDTA. In Exp. 2, in vitro fertilized oocytes were cultured with 0, 1 or 10 μg/ml Hb. Culturing with Hb did not promote porcine embryo development, but significantly increased the cell numbers of blastocysts in 1 μg/ml Hb compared to 0 or 10 μg/ml Hb. In Exp. 3, culturing embryos with 100 μM EDTA + 1 μg/ml Hb significantly improved frequencies of cleavage, blastocyst formation, and total cell numbers in blastocysts compared to the control. Moreover, 100 μM EDTA, 1 μg/ml Hb and their combination reduced reactive oxygen species (ROS) accumulation and decreased the incidence of apoptosis. In conclusion, the present study clearly demonstrated that the combining treatment of EDTA and Hb improved IVF porcine embryo development.