TIMP1 and Stroke: Previous research identified an association between serum TIMP-1 levels and TBI severity and death.56 A previous study demonstrated that the TIMP-1 gene is overexpressed in the brain at 12 h after middle cerebral artery occlusion, reaching a peak level at 2 days after stroke.57,58 High serum TIMP-1 levels are also associated with a worse prognosis after stroke.56,59 The TIMP-1 is constitutively expressed at a low level in many tissues, but after tissue injury and inflammation, TIMP-1 gene expression generally increases compared with that in healthy tissue.60,61