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.
Keywords: Brain microvascular endothelial cells; anti-TLR2 antibody (T2.5); blood-brain barrier; matrix metalloproteinases-2/9; tight junction proteins; toll like receptor-2.
Copyright © 2018. Published by Elsevier Inc.