TGFB1 and renal fibrosis: After UUO, the specific Atg7 gene deletion in renal distal TECs promoted tubulointerstitial fibrosis by upregulating plasminogen activator inhibitor 1 (PAI-1), which promoted renal fibrosis by promoting the migration of fibrogenic cells through a protease-independent pathway and activation of the transforming growth factor (TGF)-β/Smad 4 signaling pathway.