Cardiotonic steroids induce anti-angiogenic and anti-proliferative profiles in first trimester extravillous cytotrophoblast cells

Abstract Objective Preeclampsia (preE), is characterized by abnormal placental invasion and function. Marinobufagenin (MBG), a cardiotonic steroid (CTS), inhibits cytotrophoblast (CTB) cell functions that are critical for normal placental development. This study tests the hypothesis that CTSs induce anti-angiogenic and anti-proliferative effects in CTB cells. Methods Human extravillous CTB cells of the line Sw-71, derived from first trimester chorionic villus tissue, were incubated with 0, 0.1, 1, 10, and 100 nM of each of three CTSs (MBG, cinobufatalin (CINO) and ouabain (OUB)) for 48 h. Thereafter, levels of pro-angiogenic (vascular endothelial growth factor (VEGF165), placental growth factor (PlGF)) and anti-angiogenic (soluble fms-like tyrosine kinase-1 (sFlt-1), soluble endoglin (sEng)) factors were measured in culture media using ELISA kits. Expression of three receptors (VEGF receptor 1 (VEGFR1), angiogenic angiotensin type 1 receptor (AT1 ) and anti-angiogenic angiotensin type 2 receptor (AT2 )) were assayed using immunoblotting (western blots) in cell lysates. Results sFlt-1 and sEng secretion were increased while VEGF165 and PIGF were decreased in the culture media of CTB cells treated with 1 nM or more of each CTSs ( p