TGFB1 and renal fibrosis: During renal fibrosis linked with ER stress, TGF-β acts as a major regulator in renal tubular epithelial cells through the PI3K/Akt, Notch signaling, and Wnt/β catenin pathways [2, 30] via transcriptional factors such as Zeb1, Snail, TWIST1 [31].