In hyperhomocysteinemia mice, 5-aza-2’-deoxycytidine (Aza), a DNA methyltransferase (DNMT1) inhibitor, reduced high BP and vascular stiffening via reduced expression of matrix metalloproteinases 9 (MMP9), and tissue inhibitors of metalloproteinases (TIMPs)12. Here, MMP9 is linked to hyperhomocysteinemia.