Fig. 2

The available evidence to summarize the early to late periods of intracellular cell interactions in the glomerulus. During the progression of DKD, the mechanisms of intracellular cell interactions in the glomerulus at different stages have different emphases. In the early stage of DKD, there is a tendency towards loss of podocytes and angiogenesis disorders, and the glomerular filtration barrier begins to be damaged. With more ROS being produced, the progression of DKD develops further. In the transitional period, mesangial expansion and sclerosis accompanied by overproduction of ECM, gradually lead to renal fibrosis and ultimately develop into the late-stage of DKD. The over-activation of a series of renal fibrotic pathways with TGFΒ as the core and the release of exosomes of related signal transmitters eventually aggravate the renal fibrotic process of DKD, resulting in a sharp decline in renal function and developing into the end-stage renal disease