Cepharanthine maintains integrity of the blood-brain barrier (BBB) in stroke via the VEGF/VEGFR2/ZO-1 signaling pathway

Dysfunction of tight junctions such as zonula occludens protein-1 (ZO-1)-associated aggravation of blood-brain barrier (BBB) permeability plays an important role in the progression of stroke. Cepharanthine (CEP) is an extract from the plant Stephania cepharantha. However, the effects of CEP on stroke and BBB dysfunction have not been previously reported. In this study, we report that CEP improved dysfunction in neurological behavior in a middle cerebral artery occlusion (MCAO) mouse model. Importantly, CEP suppressed blood-brain barrier (BBB) hyperpermeability by increasing the expression of ZO-1. Notably, we found that CEP inhibited the expression of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor 2 (VEGFR2) in the cortex of MCAO mice. Additionally, the results of in vitro experiments demonstrate that treatment with CEP ameliorated cytotoxicity of human bEnd.3 brain microvascular endothelial cells against hypoxia/reperfusion (H/R). Also, CEP attenuated H/R-induced aggravation of endothelial permeability in bEND.3 cells by restoring the expression of ZO-1. Further study proved that the protective effects of CEP are mediated by inhibition of VEGF-A and VEGFR2. Based on the results, we conclude that CEP might possess a therapeutic prospect in stroke through protecting the integrity of the BBB mediated by the VEGF/VEGFR2/ZO-1 axis.