PPAR-γRegulates Trophoblast Differentiation in the BeWo Cell Model
Common pregnancy complications, such as severe preeclampsia and intrauterine growth restriction, disrupt pregnancy progression and impair maternal and fetal wellbeing. Placentas from such pregnancies exhibit lesions principally within the syncytiotrophoblast (SCT), a layer in direct contact with maternal blood. In humans and mice, glial cell missing-1 (GCM-1) promotes differentiation of underlying cytotrophoblast cells into the outer SCT layer. GCM-1 may be regulated by the transcription factor peroxisome proliferator-activated receptor-gamma (PPAR-γ); in mice, PPAR-γpromotes labyrinthine trophoblast differentiation via Gcm-1, and, as we previously demonstrated, PPAR-γactivation ameliorates disease features in rat model of preeclampsia. Here, we aimed to characterize the baseline activity of PPAR-γin the human choriocarcinoma BeWo cell line that mimics SCT formationin vitroand modulate PPAR-γactivity to study its effects on cell proliferation versus differentiation. We report a novel negative autoregulatory mechanism between PPAR-γactivity and expression and show that blocking PPAR-γactivity induces cell proliferation at the expense of differentiation, while these remain unaltered following treatment with the agonist rosiglitazone. Gaining a deeper understanding of the role and activity of PPAR-γin placental physiology will offer new avenues for the development of secondary prevention and/or treatment options for placentally-mediated pregnancy complications.