CASP3 and diabetes mellitus: It should be noted that although there was no significant increase in caspase-3 cleavage and TUNEL-positive cells at late stages of DM (3 and 6 months, Figs. 4a,b), consistent with our and other previous studies4,5,7, Western blot (Fig. 4e) revealed a significant increase in p53 protein expression both at the early stage (0.5 month) and at other time points (3 and 6 months) in DM groups.