TGFB1 and diabetes mellitus: To further examine the preventive effect of SFN on diabetes-induced aortic fibrosis, immunohistochemical staining showed the increased expression of two important pro-fibrotic mediators, CTGF and TGF-β1 (Figure 3A,B), in aortic tunica media of DM mice, particularly at the 6 month time-point.