Besides, as a key factor of DKD, hypoxia can stimulate the increase of endothelial PDGF-B mRNA and enhance the specific binding capacity between PDGF-B and PDGFR-β, thus regulating the PDGF-B paracrine interactions between GECs and MCs, which causes mesangial expansion [109]. This evidence concerns the gene PDGFRB and diabetic kidney disease.