Moreover, it has been suggested that the local interaction between VEGF-A and its receptors, but not VEGF-A expression, is tightly regulated in diabetes [28] The ambiguous role of VEGF-A in the development of DN is also reflected in the results of therapies based on the inhibition of VEGF-A-induced signalling, leading to increased protein excretion in the urine, among other things, suggesting that certain amounts of VEGF-A are needed to maintain normal glomerular function [29]. Here, VEGFA is linked to diabetes mellitus.