TGFB1 and renal fibrosis: Studies have demonstrated that TGF-β/SMAD mediated EndMT could contribute to early renal fibrosis in diabetic mice (Li et al., 2009; Srivastava et al., 2021), and glomerulus EndMT could also induce epithelial mesenchymal transformation (EMT) of renal tubular epithelial cells (TECs) (Srivastava et al., 2021), which might work together to accelerate the process of renal fibrosis in DKD (Li et al., 2020a).