PCNA and type 2 diabetes mellitus: The next study was conducted to further examine the effect of SFN on the cell death and proliferation by TUNEL staining (Figure 6(a)) and PCNA staining (Figure 6(b)), which showed significant increases of apoptotic cell death and proliferation in the aortas of T2DM mice, but not in the aortas of diabetic mice with SFN administration (DM/SFN group).