title: Effect of baicalin on matrix metalloproteinase-9 expression and blood-brain barrier permeability following focal cerebral ischemia in rats.
abstract: Focal cerebral ischemia results in an increased expression of matrix metalloproteinase-9 (MMP-9), which induces vasogenic brain edema via disrupting the blood-brain barrier (BBB) integrity. Recent studies from our laboratory showed that baicalin reduces ischemic brain damage by inhibiting inflammatory reaction and neuronal apoptosis in a rat model of focal cerebral ischemia. In the present study, we first explored the effect of baicalin on the neuronal damage, brain edema and BBB permeability, then further investigated its potential mechanisms. Sprague-Dawley rats underwent permanent middle cerebral artery occlusion (MCAO). Baicalin was administrated by intraperitoneally injected twice at 2 and 12 h after the onset of MCAO. Neuronal damage, brain edema and BBB permeability were measured 24 h following MCAO. Expression of MMP-9 protein and mRNA were determined by western blot and RT-PCR, respectively. Expression of tight junction protein (TJP) occludin was detected by western blot. Neuronal damage, brain edema and BBB permeability were significantly reduced by baicalin administration following focal cerebral ischemia. Elevated expression of MMP-9 protein and mRNA were significantly down-regulated by baicalin administration. In addition, MCAO caused the decreased expression of occludin, which was significantly up-regulated by baicalin administration. Our study suggested that baicalin reduces MCAO-induced neuronal damage, brain edema and BBB permeability, which might be associated with the inhibition of MMP-9 expression and MMP-9-mediated occludin degradation.
authors.affiliation: Department of Neurosurgery, The Affiliated Union Hospital of Fujian Medical University, Fujian Neurosurgical Institute, 29# Xinquan Road, Fuzhou, 350001 Fujian, China. unionnstu@hotmail.com
authors.forename: Xian-kun
authors.initials: XK
authors.lastname: Tu
authors.forename: Wei-zhong
authors.initials: WZ
authors.lastname: Yang
authors.forename: Ri-sheng
authors.initials: RS
authors.lastname: Liang
authors.forename: Song-sheng
authors.initials: SS
authors.lastname: Shi
authors.forename: Jian-ping
authors.initials: JP
authors.lastname: Chen
authors.forename: Chun-mei
authors.initials: CM
authors.lastname: Chen
authors.forename: Chun-hua
authors.initials: CH
authors.lastname: Wang
authors.forename: Hai-shu
authors.initials: HS
authors.lastname: Xie
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.forename: Long-qiang
authors.initials: LQ
authors.lastname: Ouyang
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000187:drug effects*; D001929:Brain Edema / Q000209:etiology; D002545:Brain Ischemia / Q000150:complications / Q000503:physiopathology*; D005419:Flavonoids / Q000494:pharmacology*; D020244:Infarction, Middle Cerebral Artery / Q000503:physiopathology*; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis*; D008565:Membrane Proteins / Q000378:metabolism; D062793:Occludin; D010539:Permeability / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D005419:Flavonoids; D008565:Membrane Proteins; D062793:Occludin; C568987:Ocln protein, rat; C038044:baicalin; D020780:Matrix Metalloproteinase 9