TGF-β1 is known to drive renal fibrosis via down-stream Smad-dependent signaling and is involved in epithelial-mesenchymal transition and in the regulation of ECM turnover through the induction of pro-fibrotic molecules, including α-SMA, collagen 1 and MMP9 [16,42,45]. This evidence concerns the gene MMP9 and renal fibrosis.