Showing papers by "Jiangang Shen published in 2009"
TL;DR: It is suggested that NBO attenuates early BBB disruption, and inhibition of MMP‐9‐mediated occludin degradation is an important mechanism for this protection.
Abstract: Early blood-brain barrier (BBB) disruption resulting from excessive neurovascular proteolysis by matrix metalloproteinases (MMPs) is closely associated with hemorrhagic transformation events in ischemic stroke. We have shown that normobaric hyperoxia (NBO) treatment reduces MMP-9 increase in the ischemic brain. The aim of this study was to determine whether NBO could attenuate MMP-9-mediated early BBB disruption following ischemic stroke. Rats were exposed to NBO (95% O(2)) or normoxia (30% O(2)) during 90-min middle cerebral artery occlusion, followed by 3-hour reperfusion. NBO-treated rats showed a significant reduction in Evan's blue extravasation in the ischemic hemisphere compared with normoxic rats. Topographically, Evan's blue leakage was mainly seen in the subcortical regions including the striatum, which was accompanied by increased gelatinolytic activity and reduced immunostaining for tight-junction protein, occludin. Increased gelatinolytic activities and occludin protein loss were also observed in isolated ischemic microvessels. Gel gelatin zymography identified that MMP-9 was the main enzymatic source in the cerebral microvessels. Incubation of brain slices or isolated microvessels with purified MMP-9 revealed specific degradation of occludin. Inhibition of MMP-9 by NBO or MMP-inhibitor, BB1101, significantly reduced occludin protein loss in ischemic microvessels. These results suggest that NBO attenuates early BBB disruption, and inhibition of MMP-9-mediated occludin degradation is an important mechanism for this protection.
171 citations
TL;DR: This study is the first time to demonstrate that CRAE has hepatoprotective effect on acute liver injuries induced by CCl4, and the results suggest that the effect of CRAE against CCl 4-induced liver damage is related to antioxidant property.
95 citations
TL;DR: The results showed that compounds such as 6b, 6d, 6h, and 6k possess significant antiproliferative activity against MCF-7 cell line with the IC(50) values of 7.2, 5.3, 3.5 microM, respectively.
31 citations
TL;DR: This study investigated the feasibility of using EPRI with specifically designed nitroxides to map the changes of O2 concentration in mouse brain after focal ischemia and observed a decrease in the size of the hypoxic region when the mouse breathed higher levels of O 2.
Abstract: Electron paramagnetic resonance imaging (EPRI) is a new modality for visualizing O2 distribution in tissues, such as the brain after stroke or after administration of drugs of abuse. We have recent...
24 citations