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Objective:To evaluate the effect of flurbiprofen postconditioning on the permeability of blood brain barrier in a rat model of focal cerebral ischemia-reperfusion (I/R) injury.Methods:Eighty healthy male Wistar rats, aged 8-9 weeks, weighing 280-320 g, were divided into 4 groups ( n=20 each) using a random number table method: sham operation group (group Sham), focal cerebral I/R group (group I/R), lipo-microballoons group (group V) and flurbiprofen 10 mg/kg group (group F). Focal cerebral I/R model was established by left middle cerebral artery occlusion for 2 h followed by 24-h reperfusion in anesthetized rats.Flurbiprofen 10 mg/kg (group F), the equal volume of lipo-microballoons (group V) or the equal volume of normal saline (group Sham and group I/R) was injected via the tail vein at the onset of reperfusion.The rats were sacrificed at 24 h of reperfusion, brains were immediately removed, and cerebral tissues were obtained for measurement of brain water content, Evans blue content, expression of matrix metalloproteinase-9 (MMP-9) in ischemic penumbra (by immuno-histochemistry), and expression of phosphorylated p38 mitogen-activated protein kinase (p-p38 MAPK) and inducible nitric oxide synthase (iNOS) in ischemic penumbra (by Western blot). Results:Compared with Sham group, brain water content and Evans blue content in brain tissues were significantly increased, and the expression of MMP-9, p-p38 MAPK and iNOS in ischemic penumbra was up-regulated in I/R, V and F groups ( P<0.05). Compared with group I/R, brain water content and Evans blue content in brain tissues were significantly decreased, and the expression of MMP-9, p-p38 MAPK and iNOS in ischemic penumbra was down-regulated in group F ( P<0.05), and no significant change was found in the above parameters in group V ( P>0.05). Conclusion:Flurbiprofen postconditioning can decrease the permeability of blood brain barrier during focal cerebral I/R in rats, and the mechanism may be related to inhibiting the activation of p38 MAPK/iNOS signaling pathway and down-regulating the expression of MMP-9.
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This study is to investigate the effect of hydroxyethylpuerarin on the expression of tumor necrosis factor-alpha (TNF-α) and activity of nuclear factor kappa B (NF-κB) after middle cerebral artery occlusion (MCAO) in rats. Rats were subjected to cerebral ischemia-reperfusion injury induced by MCAO. Hydroxyethylpuerarin (10, 20, 40 mg·kg-1, iv) was administered just 30 min before occlusion and immediately after reperfusion. After a 24 h reperfusion following 2 h of MCAO, the number of viable neurons in hippocampal CA1 region was counted by hematoxylin and eosin (HE) staining. TNF-α protein and its mRNA expression were examined with radioimmunoassay (RIA) and reverse transcriptase-polymerase chain reaction (RT-PCR) respectively. NF-κB activity was observed by electrophoretic mobility shift assay (EMSA), and inhibition of NF-κB α (IκBα) protein expression was evaluated by Western blotting analysis. Animals treated with hydroxyethylpuerarin had a significant increase in neuronal survival in comparison with vehicle-treated group. Hydroxyethylpuerarin significantly reduced the protein and mRNA expression of TNF-α following 2 h of ischemia with 24 h of reperfusion. NF-κB DNA binding activity and the degradation of IκBα in the cytoplasm also decreased by hydroxyethylpuerarin treatment. The protective effects of hydroxyethylpuerarin against ischemia-reperfusion injury may be mediated by decreasing the expression of TNF-α and the activity of NF-κB in rats.
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The aim of this study is to investigate the effect and mechanism of angiotensin (Ang) II on E-selectin and vascular cell adhesion molecule-1 (VCAM-1) expression in rat brain microvascular endothelial cells (BMEC) and evaluate the effect of compound EXP-2528, a novel Ang Ⅱ type 1 (AT1) receptor antagonist. The experiment was performed in cultured BMEC of rat. The mRNA and protein expression of E-selectin and VCAM-1 in BMEC was analyzed by RT-PCR and Western blotting, respectively. The results showed that the mRNA and protein expression of E-selectin and VCAM-1 in BMEC were significantly upregulated by 4 h or 18 h exposure to 1×10-7 mol·L-1 Ang Ⅱ. These effects were abolished by pretreatment with the selective AT1 receptor antagonists losartan and compound EXP-2528, but not with the AT2 selective antagonist PD123319. Combining losartan with PD123319 also significantly inhibited Ang Ⅱ-induced E-selectin and VCAM-1 expression in BMEC, but there was no significant difference compared with losartan group. These findings indicated that Ang Ⅱ upregulated E-selectin and VCAM-1 in BMEC by activating AT1 receptor and then involved in the development of cerebrovascular disease.
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Aim To observe the damages induced by hydrogen peroxide in cultured bovine cerebral microvascular endothelial cells (BCMEC) and evaluate the protective effects of hydroxyethylpuerarin on hydrogen peroxide-injured BCMEC. Methods BCMEC were cultured and transferred into modified Eagle medium (MEM). The viability of cells was detected by MTT assay. Cell injury was determined by lactate dehydrogenase (LDH) activity in the extracellular medium. Flow cytometry was employed to observe the occurrence of apoptosis. Morphologic changes of cells were visualized under phase contrast and electron occurrence of apoptosis. Hydroxyethylpuerarin was shown to increase the survival rate and decrease the activity of LDH of BCMEC damaged by hydrogen peroxide. Hydroxyethylpuerarin was also found to protect BCMEC against apoptosis induced by hydrogen peroxide. Conclusion Hydrogen peroxide induces BCMEC injury either by apoptosis or through necrosis. Hydroxyethylpuerarin protects BCMEC against hydrogen peroxide-induced injury in a concentration-dependent manner. Its antioxidant effects might be involved as the mechanism protection.
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Aim To investigate the effect of low molecular N-trimethyl chloride chitosan(LMTC) on the growth of bovine vascular smooth muscle cells(BVSMCs) in vitro. Methods The antiproliferation activities of LMTC were evaluated in BVSMCs by means of crystal violet staining and MTT assay. The morphological changes of LMTC in BVSMCs were observed under transmission electron microscope. Cell survival ratio influenced by LMTC was assessed by flow cytometer. [WTHZ]Results After BVSMCs were treated by LMTC for 72 h,the growth of the cells was inhibited in vitro and was dependent on concentration; there were some changes of apoptosis by transmission electron microscope and flow cytometer. Conclusion LMTC can inhibit the proliferation of BVSMCs and induce their apoptosis.
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The effects of propylene glycol mannate sulfate (PGMS) on the lipid peroxide (MDA) , superoxide dismutase (SOD) , glutathion peroxidase (GSH-Px), nitric oxide (NO)and water content in the whole cerebral ischemia/reperfusion injury rabbits induced by four-vessel occlusion,The results show that PGMS can decrease the brain water and MDA, and can increase the SOD and GSH-Px level. No significant effect on the NO level has been detected. The results suggest that the protective effects of PGMS on ischemia/reperfusion injury may be related to its antioxidation.
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The abnormal proliferation of vascular smooth muscle cells after endothe-lial injury is postulated to be the main pathophysiological process in atherosclerosis (AS). The effects of propylene glycol mannate sulfate(PGMS) on the proliferation of bovine cerebral microvessel smooth muscle cslls (BCMSMCs) induced by 10% fetal calf serum (FCS) and interleukin l(IL-1) were investigated in culture. 5 - 8 stage subcultured BCMSMCs were incubated into 96-well dish- With either 10% FCS or IL-1 (50u/ml) to produce BCMSMCs proliferation , the inhibitory effects of PGMS on proliferation of BCMSMCs were investigated. The results shows that PGMS could inhibit the proliferation of quiescent BCMSMCs induced by 10% PCS. The growth of cells was inhibited, comparing with normal control 72hours after the serum addition as determined by crystal violet stainning and MTTmethod. The proliferation of quiescent BCMSMCs induced by IL-1 (50u/ml) was also inhibited by PGMS as determined by crystal violet stainning and MTT method. The results suggested that PGMS inhibit the proliferation of BCMSMCs induced by 10% FCS and IL-1 ,and the use of PGMS may probably play an important role in the treatment of cerebrovascular disease.
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Guan Xin Shu ( GXS ) is a heparinoid.Quails were randomly divided into 2 groups. All of them were fed with inducer diet containing 1% cholesterol and 20% fat for 6 weeks. 1 group was treated with GXS (200mg/kg/d, ip ) , the other with 0.9% NaCl(0.2ml/100g/d, ip ) . 4 and 6 weeks after administration, serum cholesterol level was significantly reduced (mean 3l%, P
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Aim To observe the influence of carvedilol on the injury and expression of intercellular adhesion molecule-1 induced by hydrogen peroxide in ECV-304 cells and investigate the anti-atherosclerotic effect of carvedilol.Methods: The viability of ECV-304 cells was detected by MTT assay.Morphological changes of ECV-304 cells were observed under converse microscope.The level of lactate dehydrogenase released to the extracellular medium,the intracellular superoxide dismutase activity and the extracellular and intracellular Malondialdelyde level were determined using automatic biochemistry analyser.The expression of ICAM-1 in protein level and mRNA level was detected with flow cytometric technique and RT-PCR.Results Pretreated with carvidilol(1.0?10~(-5)～1.0?10~(-9)mol?L~(-1)) for 24 h,the cell survival rate was increased significantly in a concentration-dependent manner.Pre-incubation for 24 h with carvedilol results in a significant concentration-dependent decline of LDH release from hydrogen peroxide(1.0?10~(-6)mol?L~(-1))injured cells.While ECV-304 cells were pre-incubated with carvedilol,the level of MDA decreased and the activity of SOD increased significantly.Carvedilol produced a concentration-dependent inhibition of the expression of ICAM-1 protein and mRNA in hydrogen peroxide injured ECV-304 cells in a similar manner.Conclusion: These experiments demonstrated that carvedilol was able to protect ECV-304 cells from the oxidative stress injury and inhibit ICAM-1expression in ECV-304 cells induced by hydrogen peroxide.Therefore,we can consider that carvedilol maintains and improves the function of endothelium damaged by hydrogen peroxide from many aspects,which does indicate extensive antioxidant effects on the hydrogen peroxide-injured vascular endothelial cells and suggest promising effects in atherogenesis process.
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AIM To examine the effects of lovastatin, probucol on the intracellular cholesterol content and cholesterol efflux. METHODS With the model of foam cells through depositing the oxidized low-density lipoprotein (OXLDL) into mouse peritoneal macrophages, intracellular cholesterol content was examined by high performance liquid chromatography after the administration of lovastatin and probucol at different concentration. RESULTS The CE/TC ratios of the model group were beyond 50% and extremely higher than those of the normal and negative groups, suggesting that the model of foam cells was established triumphantly. Lovastatin decreased intracellular TC, CE and CE/TC significantly and dose-dependently. Probucol also possessed such effects on intracellular TC, CE, but no dose-dependently, and no effect on the ratio of CE/TC. CONCLUSION The results showed lovastatin might be conducive to plagues stability by increasing cholesterol efflux from the foam cells and decreasing the intracellular cholesterol content. Probucol did not have this effect although it decreased intracellular TC and CE content.