Xiao's study demonstrated that mir-129-5p is related to renal fibrosis and acts as an inhibitor of TGF-β1 during renal fibrosis, while mir-129-5p directly targets Smad interacting protein 1 (SIP1) and the 3′UTR of the gene SOX4, inhibits its posttranscriptional activity, and decreases the expression of renal fibrosis-related proteins E-cadherin and Claudin-1 [30]. Here, CLDN1 is linked to renal fibrosis.