Hongyan Zhu1, Rongrong Dai2, Hao Fu3, Qiang Meng4. 1. Department of Clinical Laboratory, The Affiliated Hospital of Kunming University of Science and Technology, Kunming, No. 157, Jinbi Road, Xishan District, Kunming 650031, China; Department of Clinical Laboratory, The First People's Hospital of Yunnan Province, Kunming, China; Medicine Faculty of Kunming University of Science and Technology, Kunming, No. 727 Jingming Road, Chenggong District, Kunming 650093, China. 2. Department of Clinical Laboratory, The First Affiliated Hospital of Kunming Medical University, Kunming, No. 295, Xichang Road, Wuhua District, Kunming 650032, China. 3. Department of Neurology, The First People's Hospital of Yunnan Province, Kunming, China. 4. Department of Neurology, The First People's Hospital of Yunnan Province, Kunming, China. Electronic address: mq301@sina.com.
Abstract
BACKGROUND: Blood-brain barrier (BBB) disruption plays a key role in the pathophysiology of acute ischemic stroke. Matrix metalloproteinases-2/9 (MMP-2/9) have been shown to participate in the disruption of the BBB and hemorrhagic transformation after cerebral ischemia. Toll-like receptor 2 (TLR2) may also be correlated with endothelial cell injury during ischemia-reperfusion events. However, the correlation between MMP-2/9 and TLR2 on endothelial cells after ischemia has not yet been evaluated. The aim of the study was to evaluate the impact of TLR2 and MMP-2/9 on tight junction proteins (TJs) after oxygen-glucose deprivation and reoxygenation (OGDR). MATERIALS AND METHODS: Rat primary brain microvascular endothelial cells (BMECs) were cultured. Quantitative real-time PCR and western blotting were used to measure the mRNA and proteins expression of TLR2 and MMP-2/-9. The protein expression of TJs was detected by western blotting and immunofluorescence. RESULTS: MMP-9 significantly increased after OGDR. Protein and mRNA expression of TLR2 was also upregulated. However, claudin-5, occludin, collagen-Ⅳ, and ZO-1 were decreased after OGDR. When monoclonal anti-TLR2 antibody (T2.5) was added to BMECs after OGDR, MMP-9 was significantly downregulated, whereas occludin and collagen-Ⅳ had a tendency to increase. CONCLUSION: TLR2 antagonist T2.5 is able to downregulate the expression of MMP-9, and may constitute a therapeutic option for restoration of the BBB after OGDR.
BACKGROUND: Blood-brain barrier (BBB) disruption plays a key role in the pathophysiology of acute ischemic stroke. Matrix metalloproteinases-2/9 (MMP-2/9) have been shown to participate in the disruption of the BBB and hemorrhagic transformation after cerebral ischemia. Toll-like receptor 2 (TLR2) may also be correlated with endothelial cell injury during ischemia-reperfusion events. However, the correlation between MMP-2/9 and TLR2 on endothelial cells after ischemia has not yet been evaluated. The aim of the study was to evaluate the impact of TLR2 and MMP-2/9 on tight junction proteins (TJs) after oxygen-glucose deprivation and reoxygenation (OGDR). MATERIALS AND METHODS:Rat primary brain microvascular endothelial cells (BMECs) were cultured. Quantitative real-time PCR and western blotting were used to measure the mRNA and proteins expression of TLR2 and MMP-2/-9. The protein expression of TJs was detected by western blotting and immunofluorescence. RESULTS:MMP-9 significantly increased after OGDR. Protein and mRNA expression of TLR2 was also upregulated. However, claudin-5, occludin, collagen-Ⅳ, and ZO-1 were decreased after OGDR. When monoclonal anti-TLR2 antibody (T2.5) was added to BMECs after OGDR, MMP-9 was significantly downregulated, whereas occludin and collagen-Ⅳ had a tendency to increase. CONCLUSION:TLR2 antagonist T2.5 is able to downregulate the expression of MMP-9, and may constitute a therapeutic option for restoration of the BBB after OGDR.