YiQiFuMai Lyophilized Injection ameliorates tPA-Induced hemorrhagic transformation by inhibiting cytoskeletal rearrangement associated with ROCK1 and NF-κB signaling pathways

Abstract Ethnopharmacological relevance Thrombolytic therapy with tissue plasminogen activator (tPA) after ischemic stroke exacerbates blood–brain barrier (BBB) breakdown and leads to hemorrhagic transformation (HT). YiQiFuMai Lyophilized Injection (YQFM) is a modern preparation derived from Sheng-mai San, (a traditional Chinese medicine). YQFM attenuates the BBB dysfunction induced by cerebral ischemia–reperfusion injury. However, whether YQFM can suppress tPA-induced HT remains unknown. Aim of the study We investigated the therapeutic effect of YQFM on tPA-induced HT and explored the underlying mechanisms in vivo and in vitro to improve the safety of tPA use against stroke. Methods Male C57BL/6J mice were subjected to 45 min of ischemia and 24 h of reperfusion. tPA (10 mg/kg) were infused 2 h after occlusion and YQFM (0.671 g/kg) was injected 2.5 h after occlusion. The in vitro effect of YQFM (100, 200, 400 μg/mL) was observed in tPA (60 μg/mL)-induced dysfunction of the microvascular endothelial barrier in the brain following oxygen-glucose deprivation/reoxygenation (OGD/R) in bEnd.3 cells. Results YQFM suppressed tPA-induced high hemoglobin level in the brain, mortality, neurologic severity score, BBB permeability, expression and activation of matrix metalloproteinase (MMP)-9 and MMP-2, and degradation of tight-junction proteins. Furthermore, YQFM significantly blocked tPA-induced brain microvascular endothelial permeability and phosphorylation of Rho-associated kinase (ROCK)1, myosin light chain (MLC), cofilin and p65 in vivo and in vitro. Conclusion YQFM suppressed tPA-induced HT by inhibiting cytoskeletal rearrangement linked with ROCK-cofilin/MLC pathways and inhibiting the nuclear factor-kappa B pathway to ameliorate BBB damage caused by tPA.