As shown in Figure 1A, administration of 150 mg kg−1 of CE dramatically reduced α‐SMA and ECM (fibronectin and Collagen I) levels in mice received unilateral ureteral obstruction (UUO) surgery, a widely used animal model of kidney fibrosis.[19] Since activated renal fibroblasts are well‐recognized culprits in kidney fibrosis, we then moved on to determine the effects of W. chamaedaphne on these cells by utilizing TGF‐β1‐stimulated rat kidney fibroblast normal rat kidney‐49F (NRK‐49F) as an in vitro model. Here, ACTA1 is linked to Ureteral obstruction.