It has been reported that HHcy relates with both stroke (ischemic or hemorrhagic, via inducing cerebrovascular atherosclerosis and atherothrombosis in the first case, and probably via upregulation of matrix metalloproteinases-9 (MMP-9) expression, which takes responsibility for atherosclerotic plaque instability and rupture, in the second ones [140]) and intracranial hemorrhage incidence. Here, MMP9 is linked to intracranial hemorrhage.