GDF-11 stimulates human extravillous trophoblast cell invasion by upregulating ANGPTL4 expression.

IN BRIEF: How extravillous trophoblast (EVT) invasion is regulated during placental development remains an important question in reproductive biology. This study demonstrates that growth differentiation factor-11 (GDF-11) promotes EVT invasion by upregulating angiopoietin-like 4 (ANGPTL4) via ALK4/ALK5-SMAD3 signaling, revealing a novel mechanism in placental biology.

ABSTRACT: Proper regulation of extravillous trophoblast (EVT) cell invasion is critical for normal placental development and function. Growth differentiation factor 11 (GDF-11), a member of the transforming growth factor-β (TGF-β) superfamily, has been shown to promote EVT cell invasion, yet the underlying molecular mechanisms remain largely unclear. In this study, RNA sequencing identified angiopoietin-like 4 (ANGPTL4), a multifunctional secreted protein, as a novel downstream target of GDF-11. In vitro experiments demonstrated that GDF-11 significantly upregulated ANGPTL4 expression in both HTR-8/SVneo cells and primary human EVT cells. Mechanistically, we found that the type I TGF-β receptors ALK4 and ALK5 were essential for mediating the stimulatory effect of GDF-11 on ANGPTL4 expression. Further analysis revealed that SMAD3, but not SMAD2, was the key transcription factor involved in this process. Using both loss- and gain-of-function approaches, we demonstrated that ANGPTL4 was required for GDF-11-induced EVT cell invasion. Importantly, serum levels of GDF-11 were markedly reduced in patients with preeclampsia (PE), a pregnancy disorder associated with shallow trophoblast invasion and poor placentation. Together, our findings uncover a previously unrecognized GDF-11-ANGPTL4 signaling axis that regulates EVT cell invasion and provides new insight into the pathophysiology of PE.