DNMT1 and diabetes mellitus: Diabetic sham rat hearts exhibited a significant increase in the expression of DNMT1 and 3A and 3B gene expression by 2.8 and 2.4 folds, respectively, which was further elevated in DM-I/R hearts to 4.4, 3.7, and 3.4 folds, respectively (Figure 3b) compared to the sham hearts.