Effects of melatonin on gene expression of IVM/IVF porcine embryos

The effect of melatonin on in vitro embryo development and the expression of antioxidant enzyme gene in preimplantation porcine embryos was determined by modified semi-quantitative single cell RT-PCR. Porcine embryos derived from in vitro maturation /in vitro fertilization were cultured in 5% CO₂ and 20% O₂ at 37°C in NCSU23 medium. Melatonin was added to medium at concentration of 1 nM, 5 nM, and 10 nM. When treated with 1nM (39.0%) of melatonin, the developmental rate of embryos beyond the morula stage were higher than that of control group (31.0%) (p<0.05). Number of inner cell mass and tropectoderm cell in control (23.0±0.5 and 17.3±0.8), 1 nM (23.6±0.6 and 19.0±0.5), and 5 nM (23.3±1.1 and 16.3±0.8) treated with melatonin were higher than in 10 nM (20.0±0.5 and 13.3±0.8) treated with melatonin (p<0.05). To develop an mRNA phenotypic map for the expression of catalase, bax and caspase-3, single cell RT-PCR analysis were carried out in porcine IVM/IVF embryo. Catalase was detected in 0, 1 and 5 nM supplemented with melatonin, but bax and caspase-3 were detected in 10 nM treated with melatonin.