As VEGF and ANGPTL4 expression are increased by hypoxia in the regulation of tight junction structure and function in trophoblast cells [61], the findings correlate PPARs and hypoxia with abnormal trophoblast differentiation and placental insufficiency syndromes of preeclampsia (PE) and intrauterine growth restriction (IUGR) [62,63] (Figure 4). Here, ANGPTL4 is linked to fetal growth restriction.