DNMT1 and brain infarction: DNMT activity evaluation in the mitochondria using 5mC and TIMP-2 methylation assays revealed that, after cerebral infarction, the mRNA and protein expression of DNMT1 and DNMT3a was increased, DNMT activity was increased, and methylation of TIMP-2 DNA was increased; these effects were reversed by 5-aza-dC treatment [48].