Effects of Bisphenol A on expression of genes related to amino acid transporters, insulin- like growth factor, aquaporin and amino acid release by porcine trophectoderm cells

The peri-implantation period of pregnancy is critical for conceptus development, implantation, and signaling for establishment of pregnancy. This study evaluated the effects of bisphenol A (BPA) on proliferation, adhesion, and migration of porcine trophectoderm (pTr2) cells, expression of transporters of arginine and synthesis of amino acids. All concentrations of BPA decreased proliferation and adhesion of pTr2 cells after 96 h compared to the control group. Lower concentrations of BPA (1 x 10(-9), 1 x 10(-8), 10(-7)M) increased (P< 0.05), but higher concentrations of BPA (1 x 10(-5), 1 x 10(-4) M) decreased migration of pTr2 cells. BPA increased expression of SLC7A1 mRNA at lower concentrations (1 x 10(-9) to 1 x 10(-6)M) and SL7A6, another cationic acid transporter, at higher concentrations (1 x 10(-5), 1 x 10(-4) M). BPA also down-regulated the expression of IGF1 and IGF1 receptor at concentrations of 1 x 10(-7) to 1 x 10(-4) M compared to the control group. The expression of mRNAs for aquaporins (AQP) 3 and 4 were reduced at all concentrations of BPA, but at lower concentrations of BPA, (1 x 10(-9) to 1 x 10(-8)M) expression of AQP9 mRNA increased and the expression of AQP11 was not affected by BPA (P> 0.05). There was an inhibitory effect of BPA on the release of synthesis of asparagine, threonine, taurine, tryptophan, and ornithine into the culture medium by pTr2 cells. Collectively, BPA adversely affected the expression of transporters for cationic amino acids like arginine, as well as AQPs, IGF1, and IGF1R associated with proliferation, migration, and adhesion of pTr2 cells. Those adverse effects would likely increase pregnancy losses during the peri-implantation period of pregnancy.