Renal tubulointersitial fibrosis was reduced as represented by trichrome positive area, TGF-β, α-SMA, and fibronectin expression in fenofibrate treated group (i.e. decreases in trichrome and TGF-β1 positive areas by 72.6% and 58.8%, respectively) (Fig. 4C,D). This evidence concerns the gene TGFB1 and fibrosis.