Inhibition of Ezh2 ameliorated its glucose-induced recruitment at the MMP-9 promoter and decreased MMP-9 mRNA and activity; the reason for decreased Ezh2 binding at the MMP-9 promoter by DZNep could be its degradation by DZNep, reducing Ezh2 protein levels.38 Our previous work using MMP-9 knock-out mice has clearly shown that in diabetes, in addition to the retina being protected from accelerated capillary cell apoptosis and pathology characteristic of retinopathy, they have normal mitochondrial structure and mtDNA transcription. This evidence concerns the gene MMP9 and diabetes mellitus.