PLAC1 Regulates the Occurrence of Fetal Growth Restriction by Inhibiting the Apoptosis of Trophoblast Cells

The expression of PLAC1 was reduced in fetal growth restriction and did not protect trophoblast cells from hypoxic damage, suggesting that PLAC1 may be an important regulator in the occurrence of fetal growth restriction.

Western blotting was used to detect the expression of PLAC1 in FGR and in normal placenta tissues. Cell counting kit 8 (CCK-8), wound healing, and transwell assays were used to detect the effects of PLAC1 knockdown on trophoblast cell proliferation, migration, and invasion. Western blotting was used to detect the expression of PLAC1 under hypoxic conditions, and the cell viability and apoptosis of trophoblast cells in a low oxygen concentration after overexpression of PLAC1 were detected by CCK-8 and flow cytometry assay.

Fetal growth restriction (FGR) refers to impaired and insufficient intrauterine growth potential caused by a variety of adverse factors and is a serious perinatal complication that leads to fetal or neonatal mortality and morbidity. FGR has numerous causes, and its pathogenesis has not been fully understood. Recently, increasing numbers of researchers have begun to focus on the placenta, the only link between the fetus and the mother. The placenta is a vital organ that plays key roles in fetal development. PLAC1 is a trophoblast-specific gene located on the X chromosome and is important for placental development. However, the biological role of PLAC1 in fetal growth restriction is not well understood. In this study, we investigated the changes in the expression of placental-specific protein 1(PLAC1) in the placentas of pregnant women with FGR and in the placentas of normal pregnancies. We also explored the regulation of PLAC1 in the growth of trophoblast cells.

Compared with the placentas in the control group of normal pregnancies, the expression of PLAC1 in the placentas of the FGR group was significantly down-regulated (p<0.05). Knocking down PLAC1 by siRNA significantly inhibited the proliferation, migration, and invasion of trophoblast cells. After treatment with alow oxygen concentration, the expression of PLAC1 protein was significantly reduced (p<0.05). The overexpression of PLAC1 can reverse the cell viability of trophoblast cells (p<0.05) and inhibit apoptosis of trophoblast cells (p<0.05) in low oxygen concentration.