The in vivo protective effects of AAT can be seen from the significant decrease in the renal fibrosis area and attenuation of the changes in EMT markers such as E-cadherin and collagen I. Furthermore, AAT co-treatment with TGF-β1 could reverse TGF-β1 mediated EMT in MDCK cells, suggesting that AAT modulated TGF-β1 pathway to reduce EMT and renal fibrosis. This evidence concerns the gene SERPINA1 and renal fibrosis.