Several db/db mouse model studies of type 2 diabetes mellitus (T2DM) found that different chromatin-based histone PTMs were observed in the promoters of PAI1 and AGER (encoding age-specific receptor RAGE) and enhanced the RNA polymerase II recruitment, suggesting that activating and inhibitory epigenetic markers jointly facilitate chromatin unwinding and improve the recruitment of transcription factors to the genes associated with DKD. This evidence concerns the gene SERPINE1 and type 2 diabetes mellitus.