PDGFR-β restores blood-brain barrier functions in a mouse model of focal cerebral ischemia:

Although platelet-derived growth factor receptorbeta (PDGFR-β) mediates the recruitment of vascular pericytesinto ischemic lesion to restore the blood-brain barrier (BBB) dysfunction, its mechanisms still remain elusive. Compared with control PDGFR-βfloxed/ floxedmice ( Floxed), postnatally induced systemic PDGFR-β knockout mice (Esr-KO) not only showed severe brain edema, neurologic functional deficits, decreased expression of tight junction(TJ) proteins, abundant endothelial transcytosis, and deformed TJs in the BBB, but also showed reduced expression of transforming growth factor-β (TGF-β) protein after photothrombotic middle cerebral artery occlusion (MCAO). In endothelial- pericyteco-culture, an in vitro model of BBB, the increment in the barrier functionof endothelial monolayer induced by pericyteco-culture was completely cancelled by silencing PDGFR-β gene expression in pericytes, and was additively improved by PDGFR-β and TGF-β receptor signals under hypoxia condition. Exogenous PDGF-BB increa...