Paeonol attenuates oxygen-glucose deprivation injury and inhibits NMDA receptor activation of cultured rat hippocampal neurons / 药学学报

The purpose of this study is to determine if paeonol can protect hippocampal neurons against injury due to oxygen-glucose deprivation (OGD) injury. The rat neurons were cultured in an OGD environment and the model of OGD injury was established. Paeonol and MK-801, a positive control drug, were added before deprivation. Neuron viability was measured by the reduction of MTT; glutamate was analyzed by amino acid analyzer; binding activity of NMDA receptor was evaluated by liquid scintillation counting and the expression of NMDA receptor NR1 subunit mRNA was semiquantitatively determined by RT-PCR. Compared with OGD injury group, paeonol treatment obviously increased cell survival rate and reduced the binding activity of NMDA receptors and the release of glutamate; and down-regulating the expression of NR1 subunit. These results suggest that paeonol may exhibit its protective effect against OGD injury by the action on NMDA receptor of rats.

Hydroxyethylpuerarin attenuates focal cerebral ischemia-reperfusion injury in rats by decreasing TNF-alpha expression and NF-kappaB activity / 药学学报

This study is to investigate the effect of hydroxyethylpuerarin on the expression of tumor necrosis factor-alpha (TNF-alpha) and activity of nuclear factor kappa B (NF-kappaB) after middle cerebral artery occlusion (MCAO) in rats. Rats were subjected to cerebral ischemia-reperfusion injury induced by MCAO. Hydroxyethylpuerarin (10, 20, 40 mg x 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-alpha protein and its mRNA expression were examined with radioimmunoassay (RIA) and reverse transcriptasepolymerase chain reaction (RT-PCR) respectively. NF-KB activity was observed by electrophoretic mobility shift assay (EMSA), and inhibition of NF-kappaB alpha (IkappaBalpha) 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-alpha following 2 h of ischemia with 24 h of reperfusion. NF-kappaB DNA binding activity and the degradation of IkappaBalpha 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-alpha and the activity of NF-kappaB in rats.

Effect of compound EXP-2528 on angiotensin II-induced E-selectin and VCAM-1 expression in rat brain microvascular endothelial cells in vitro / 药学学报

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 x 10(-7) mol x 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.

Influence of effective part of Zingiber officinal on expression of monocyte chemotactic protein-1 and adhesion molecules / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effect of effective parts of Zingiber officinal (EPZ) on the adhesion of ECV-304 cells with monocytes cultivated in vitro and on the expression of monocyte chemotactic protein-1 (MCP-1) and adhesion molecules.</p><p><b>METHOD</b>The model of ECV-304 cell oxidative stress injury was established by hydrogen peroxide (H2O2). Then EPZ-contained blood serum was taken as experimental drug. The adherence of monocytes to endothelial cell were measured by method of rose Bengal. The total RNA of cells was extracted. The intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and MCP-1 mRNA expression in cells were detected by RT-PCR. MCP-1 protein expression were detected by ELISA.</p><p><b>RESULT</b>EPZ could decrease the adhesion of monocytes with ECV-304 cells obviously. Meanwhile it could diminish the expression of ICAM-1, VCAM-1 and MCP-1 in injured ECV-304 cells.</p><p><b>CONCLUSION</b>EPZ could inhibit H2O2-induced ICAM-1, VCAM-1 and MCP-1 expression in ECV-304 and could inhibit the adherence of monocytes to endothelial cell, which may result in the protect effect in endothelial cells.</p>

Protective effects of hydroxyethylpuerarin against brain astrocytes injury induced by hydrogen peroxide / 药学学报

<p><b>AIM</b>To study the protective effects of hydroxyethylpuerarin against the injury of astrocytes induced by hydrogen peroxide (H2O2).</p><p><b>METHODS</b>Experiments were performed with cells from passage 4. Plasma membrane integrity was measured by lactate dehydrogenase (LDH) release. The occurrence of apoptosis was measured by flow cytometry. The glutamate uptake of astrocytes was studied with [3H]-glutamate incorporation. Intracellular superoxide dismutase (SOD) activity and malondialdehyde (MDA) level were assessed by automatic biochemistry analyzer.</p><p><b>RESULTS</b>Compared with H2O2 injured group, the occurrence of apoptosis, levels of LDH release and intracellular MDA of astrocytes reduced in hydroxyethylpuerarin pre-treated groups, but the glutamate uptake and intracellular SOD activity of astrocytes increased.</p><p><b>CONCLUSION</b>Hydroxyethylpuerarin could reduce the occurrence of apoptosis and improve neurotrophic function of astrocytes, which may be related with its antioxidant effects during oxidative stress.</p>

Protective effects of hydroxyethylpuerarin on cultured bovine cerebral microvascular endothelial cells damaged by hydrogen peroxide / 药学学报

<p><b>AIM</b>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.</p><p><b>METHODS</b>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 microscopes.</p><p><b>RESULTS</b>Hydrogen peroxide (200 micromol x L(-1) for 4 hours) inhibited the viability of cultured BCMEC and stimulated LDH release. Hydrogen peroxide (100 micromol x L(-1) for 4 hours) induced the 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.</p><p><b>CONCLUSION</b>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.</p>