Lysophosphatidic acid (LPA) is an important signaling molecule. Here, the effect and mechanism of LPA on the preimplantation development of porcine embryos during in vitro culture (IVC) was examined. Porcine embryos were cultured in porcine zygote medium (PZM-3) supplemented with 30 μM LPA during different days. There was a significantly higher cleavage rate in Day 1-7 and significantly higher total cell number of blastocysts in Day 1-3 and Day 4-7. It was also found that messenger RNA (mRNA) expression level of PCNA, BCL2 and BAX in blastocysts obtained from D1-7 group were significantly higher and BCL2/BAX mRNA ratio in D1-3 group was significantly lower than control group but Day 4-7 and Day 1-7 groups were comparable with control group. Treatment with 20 μM PLC inhibitor significantly decreased the embryo cleavage rate and blastocyst formation rate. Moreover, LPA as an activator of PLCs, enhanced the 30 μM LPA + 20 μM U73122 group embryo cleavage rate which similar with control group. In conclusion, the results suggest that treatment with LPA during IVC improves the porcine early embryo cleavage by activation of PLC signaling pathway and regulate the mRNA expression that contribute to total cell number of blastocysts during blastocyst formation.

Lysophosphatidic acid (LPA) is an important signaling molecule which mediates many different cellular responses. The purpose of this study was to investigate the effect of in vitro culture (IVC) medium supplemented with LPA on the preimplantation embryonic development of porcine embryos derived from in vitro fertilization (IVF). Embryos derived from IVF were cultured in PZM-3 medium supplemented with 30 μM LPA on Day 1 to Day 7, Day 1 to Day 3 (early stage), or Day 4 to Day 7 (late stage), or without LPA. Moreover, the messenger RNA (mRNA) expression of obtaining blastocysts from each group were analyzed. Data were analyzed by ANOVA followed by Duncan using SPSS (Statistical Package for Social Science) mean ± SEM. There was a significantly higher cleavage rate in Day 1 to Day 7 than control (71.25% and 57.46%, respectively) and significantly higher total cell number of blastocysts in Day 1 to Day 3 and Day 4 to Day 7 than control (56.07,56.53 and 45.19, respectively). The results also showed that the mRNA expression level of PCNA, Bcl-2 and Bax in Day 1 to Day 7 group blastocysts were significantly higher than control and the expression level of Bax in Day 1 to Day 3 was also significantly higher than control. Moreover, it also showed that Bcl-2/Bax mRNA ratio in D1-3 group was significantly lower than control but D4-7 and D1-7 groups were comparable to control group. In conclusion, our results suggest that treatment with 30 μM LPA during IVC improves the porcine early embryo cleavage and the blastocyst total cell number after IVF and regulating the mRNA expression of blastocysts during blastocyst formation.