Ulinastatin protects brain against cerebral ischemia/reperfusion injury through inhibiting MMP-9 and alleviating loss of ZO-1 and occludin proteins in mice.

The effects of Ulinastatin (UTI) on the blood-brain barrier (BBB) in the acute phase of cerebral ischemia/reperfusion (I/R) are not clear. This study was to investigate the potential protective effects of UTI on the BBB and the underlying mechanisms. Male CD-1 mice were subjected to transient middle cerebral artery occlusion (tMCAO) and randomly assigned to four groups: Sham (sham-operated), tMCAO (tMCAO+0.9% saline), UTI-L (tMCAO+UTI 1500U/100g) and UTI-H (tMCAO+UTI 3000U/100g) group. UTI was administered immediately after reperfusion in the UTI-L and UTI-H groups. At 24h after reperfusion, the neurological deficit, brain water content, and infarct volume were determined. Western blot and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to examine the expression of matrix metalloproteinase (MMP)-9, Zonula occludens-1 (ZO-1) and occludin in ischemic cerebral cortex. The integrity of the BBB was assessed by the leakage of Evans blue. Compared with tMCAO group, both UTI-L and UTI-H groups showed significantly (P<0.001) ameliorated the neurological deficit (2.00±0.71 and 1.60±0.55 vs. 4.60±0.55), lessened brain water content (82.99%±0.21% and 82.05%±0.59% vs. 84.28%±0.0.57%) and decreased the infarct volume (38.52%±1.72% and 24.78%±1.20% vs. 49.48%±1.93%). In addition, significantly (P<0.001) decreased expression of MMP-9 (0.48±0.06 and 0.37±0.05 vs.0.76±0.10 for protein and 2.88±0.23 and 2.17±0.16 vs. 3.90±0.24 for mRNA) and alleviated loss of ZO-1 (0.19±0.04 and 0.24±0.05 vs. 0.25±0.03) and occludin (0.74±0.08 and 0.87±0.07 vs. 0.94±0.06) proteins were observed in both UTI-L and UTI-H groups. UTI protects the brain against ischemic injury potentially via down-regulating the expression of MMP-9 and alleviating loss of ZO-1 and occludin proteins to restore the BBB permeability.

Li XF ，Zhang XJ ，Zhang C ，Wang LN ，Li YR ，Zhang Y ，He TT ，Zhu XY ，Cui LL ，Gao BL ... -  《-》

Ulinastatin downregulates TLR4 and NF-kB expression and protects mouse brains against ischemia/reperfusion injury.

Li X ，Su L ，Zhang X ，Zhang C ，Wang L ，Li Y ，Zhang Y ，He T ，Zhu X ，Cui L ... -  《-》

KY-226 Protects Blood-brain Barrier Function Through the Akt/FoxO1 Signaling Pathway in Brain Ischemia.

KY-226 is a protein tyrosine phosphatase 1B (PTP1B) inhibitor that protects neurons from cerebral ischemic injury. KY-226 restores Akt (protein kinase B) phosphorylation and extracellular signal-regulated kinase (ERK) reduction in transient middle cerebral artery occlusion (tMCAO) damage. However, the mechanisms underlying the neuroprotective effects of KY-226 are unclear. To address this, the effects of KY-226 on blood-brain barrier (BBB) dysfunction were examined in tMCAO mice. KY-226 (10 mg/kg, i.p.) was administered to ICR mice 30 min after 2 h of tMCAO. To assess Akt or ERK involvement, wortmannin (i.c.v.) or U0126 (i.v.), selective inhibitors of PI3K and ERK, respectively, were administered to mice 30 min before ischemia. BBB integrity was assessed by Evans blue leakage 24 h post-reperfusion. The levels of tight junction (TJ) proteins, ZO-1 and occludin, were measured by western blotting; ZO-1 mRNA level was measured by RT-PCR. Compared to vehicle, KY-226 treatment prevented BBB breakdown and reduction in TJ protein levels. KY-226 treatment restored ZO-1 mRNA levels post-reperfusion. Pre-administration of wortmannin or U0126 blocked the protective effects of KY-226 on ZO-1 protein and mRNA reduction in tMCAO mice. In bEnd.3 cells, lipopolysaccharide treatment reduced mRNA and protein levels of ZO-1, an effect rescued by KY-226 treatment. Further, KY-226 treatment restored phosphorylation of pAkt (T308) and its downstream target forkhead box protein O1 (FoxO1) (S256) in bEnd.3 cells. Collectively, we demonstrate that KY-226 protects BBB integrity by restoration of TJ proteins, an effect partly mediated by Akt/FoxO1 pathway activation. Thus, protection of BBB integrity likely underlies KY-226-induced neuroprotection in tMCAO mice.

Sun M ，Shinoda Y ，Fukunaga K 《-》

IMM-H004, A New Coumarin Derivative, Improved Focal Cerebral Ischemia via Blood-Brain Barrier Protection in Rats.

IMM-H004 (7-hydroxy-5-methoxy-4-methyl-3-[4-methylpiperazin-1-yl]-2H-chromen-2-one) is a novel coumarin derivative that showed better effect in improving global cerebral ischemia in rats. However, the effects and mechanisms in focal cerebral ischemia were not clear. Blood-brain barrier (BBB) protection is a vital strategy for the treatment of cerebral ischemia. This study is to investigate whether IMM-H004 improves brain ischemia injury via BBB protection. Focal brain ischemia model was induced by middle cerebral artery occlusion for 1 hour and reperfusion (MCAO/R) for 24 hours in rats. IMM-H004 (1.5, 3, 6 mg/kg) and edaravone (positive drug, 6 mg/kg) were administered after 5 minutes of occlusion. Neurological score and TTC staining were used to evaluate the effect of IMM-H004. Evans Blue (EB) staining and electron microscopy were used to assess BBB permeability. Western blot, reverse transcription-polymerase chain reaction, and immunohistochemistry were used to detect the expression of BBB structure-related proteins. Compared with the model group, IMM-H004 in the focal brain ischemia model improved neurological function and reduced cerebral infarction size and edema content. IMM-H004 sharply reduced the EB content and alleviated BBB structure. In addition, IMM-H004 increased the level of zonula occludens (ZO-1) and occluding, decreased the level of aquaporin 4 and matrix metalloproteinase 9, either in cortex or in hippocampus. And all of these changed were related to BBB protection. IMM-H004 improved cerebral ischemia injury via BBB protection. For a potential therapy drug of cerebral ischemia, IMM-H004 merits further study.

Niu F ，Song XY ，Hu JF ，Zuo W ，Kong LL ，Wang XF ，Han N ，Chen NH ... -  《-》

Carbon monoxide-releasing molecule-3 protects against ischemic stroke by suppressing neuroinflammation and alleviating blood-brain barrier disruption.

Wang J ，Zhang D ，Fu X ，Yu L ，Lu Z ，Gao Y ，Liu X ，Man J ，Li S ，Li N ，Chen X ，Hong M ，Yang Q ，Wang J ... -  《-》