Overall, these data reveal that in addition to the anti-inflammation property of OST in various renal diseases (Zheng et al., 2013; Song W. et al., 2014; Huang and Dong, 2017), OST mitigates UUO-induced renal fibrosis mainly through reduction of fibroblast activation and EMT, at least in part, by inhibiting the TGF-β1/Smad signaling pathway. Here, TGFB1 is linked to renal fibrosis.