FLT1 and endothelial dysfunction: An angiogenic imbalance between VEGF (specifically VEGF-A), VEGF receptor 2 (VEGFR2) and the soluble vascular endothelial growth factor receptor 1 (sVEGFR1, a truncated variant of the VEGF receptor 1, VEGFR1) has been reported in many diseases, including kidney disease where modulation of VEGF signaling correlates with impaired endothelial fenestrations, endothelial dysfunction and increased proteinuria5–9.