SMAD3 and renal fibrosis: Several previous publications have highlighted that SKI retarded renal fibrosis by inhibiting levels of interleukin-6, interleukin-1β, and TNF-α (Zhang et al., 2020) and modulating TGF-β1/Smad3 and JAK2/STAT3 signaling pathways (Wu et al., 2015; Qin et al., 2021).