HMGB1 and ischemic stroke: Glycyrrhizin down-regulated the expression of NADPH oxidase and iNOS in ischemic brain tissues; inhibited the production of superoxide and peroxynitrite; decreased the expression of HMGB1, TLR2, and MMP9; and preserved type IV collagen and the tight junction protein claudin-5 thereby decreasing hemorrhagic transformation and mortality in a rat model of ischemic stroke after delayed thrombolysis (tPA infusion time as 5 h after MCAO) [56].