Effect of Salvianolic Acid B Combined with Puerarin on Pyroptosis of SH-SY5Y Cells Injured by Oxygen-glucose Deprivation/Reoxygenation / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of salvianolic acid B combined with puerarin in protecting the SH-SY5Y cells from the damage by oxygen-glucose deprivation/reoxygenation （OGD/R） based on pyroptosis. MethodSH-SY5Y cells were used to establish the model of OGD/R， and cells were classified into the control， OGD/R， 10 μmol·L-1 salvianolic acid B， 100 μmol·L-1 puerarin， 10 μmol·L-1 salvianolic acid B + 100 μmol·L-1 puerarin， and 10 μmol·L-1 NOD-like receptor protein 3 （NLRP3） inhibitor MCC950 groups. Except the control group， other groups were rapidly reoxygenated for 12 h after 6 h OGD for modeling. The cell survival rate was determined by the methyl thiazolyl tetrazolium （MTT） assay. An optical microscope was used to observe the cell morphology. A spectrophotometer was used to determine the content of lactic dehydrogenase （LDH） in culture supernatant. Cell damage was measured by Hoechst/PI staining. The mRNA levels of NLRP3， cysteinyl aspartate specific proteinase-1 （Caspase-1）， gasdermin D （GSDMD）， apoptosis-associated speck-like protein （ASC）， and interleukin-1β （IL-1β） were determined by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The protein activation of Caspase-1 and NLRP3 was detected by immunofluorescence. Western blot was employed to determine the protein levels of IL-1β， ASC， NLRP3， Caspase-1， and cleaved Caspase-1. ResultCompared with the control group， the OGD/R group showed decreased cell survival rate （P<0.01）， damaged cell morphology， increased leakage rate of LDH （P<0.01）， up-regulated mRNA levels of NLRP3， Caspase-1， GSDMD， ASC， and IL-1β （P<0.01）， and up-regulated protein levels of IL-1β， ASC， NLRP3， Caspase-1， and cleaved Caspase-1 （P<0.01）. Compared with the OGD/R group， salvianolic acid B， puerarin， and salvianolic acid B combined with puerarin improved cell survival rate （P<0.01）， and the combined treatment group outperformed salvianolic acid B and puerarin used alone （P<0.01）. Salvianolic acid B combined with puerarin and MCC950 both improved cell morphology， reduced the leakage of LDH （P<0.01）， alleviated cell damage， and down-regulated the mRNA levels of NLRP3， Caspase-1， GSDMD， ASC， and IL-1β （P<0.05， P<0.01） and also the protein levels of IL-1β， ASC， NLRP3， Caspase-1， and cleaved Caspase-1 （P<0.05， P<0.01）. ConclusionThe results indicated that salvianolic acid B combined with puerarin can alleviate the OGD/R-induced damage of SH-SY5Y cells by inhibiting pyroptosis.

Effect of CXC chemokine receptor 7 on cell cycle of neuronal cells in ischemic stroke / 中华危重病急救医学

Objective:To investigate the function and mechanism of CXC chemokine receptor 7 (CXCR7) in neuronal cells of ischemic stroke.Methods:The expression of CXCR7 in human neuroblastoma SH-SY5Y cells was interfered by small interfering RNA (si-RNA) technique. Oxygen-glucose deprivation/reoxygenation (OGD/R) injury model was constructed in SH-SY5Y cells. CXCR7 protein expression and cell cycle were detected by flow cytometry (FCM). The protein expression of CXCR7 and Akt signaling pathway was detected by Western blotting.Results:After 6 hours of OGD/R, the expression of CXCR7 was significantly decreased compared with OGD/R 0 hour (CXCR7/GAPDH: 0.483±0.098 vs. 1.000±0.000 by Western blotting and 0.686±0.0524 vs. 1.000±0.000 by FCM, both P < 0.01), cell cycle arrest in G0/G1 phase (1.190±0.040 vs. 1.000±0.000, P < 0.01). After CXCR7 si-RNA interference with SH-SY5Y cells, OGD/R was constructed again for 6 hours. Compared with negative control group (si-NC group) under the same environment, the expression of CXCR7 and phosphorylated Akt (p-Akt) was significantly decreased (CXCR7/GAPDH: 0.471±0.051 vs. 1.000±0.000, p-Akt/GAPDH: 0.616±0.027 vs. 1.000±0.000, both P < 0.001) and cell cycle arrest in G0/G1 phase (1.105±0.033 vs. 1.000±0.000, P < 0.05). Conclusion:The CXCR7 could regulate the cycle of neuronal cells in ischemic stroke through Akt signaling pathway, which has a protective effect on neuronal cells.

Protective Effect of Salviae Miltiorrhizae Radix et Rhizoma and Puerariae Lobatae Radix Extract on SH-SY5Y Cells Injured by Oxygen-glucose Deprivation/Reoxygenation / 中国实验方剂学杂志

ObjectiveTo explore the protective effect of Salviae Miltiorrhizae Radix et Rhizoma and Puerariae Lobatae Radix （SP） extract on oxygen-glucose deprivation/reoxygenation （OGD/R）-injured SH-SY5Y cells based on oxidative stress and apoptosis. MethodThe extracts of the two medicinal materials mixed in different ratios were prepared. Human neuroblastoma SH-SY5Y cells were cultured in vitro and the injury was induced by OGD/R. Cell counting kit-8 （CCK-8） assay was used to screen the optimal ratio of the two medicinals and then the extract was used for further experiment. SH-SY5Y cells were classified into normal control group， OGD/R group， and low-， medium-， and high-dose SP （2∶1） extract groups （10， 30， 100 mg·L-1， respectively）. Cells in the groups， except the normal control group， were rapidly reoxygenated for 12 h after 4 h OGD for modeling. Then cell viability was detected by CCK-8 and cell morphology was observed under the microscope. The release rate of lactate dehydrogenase （LDH）， superoxide dismutase （SOD） activity， and content of glutathione （GSH） and malondialdehyde （MDA） were determined by spectrophotometry. The level of reactive oxygen species （ROS） was detected with 2，7-dichlorodihydrofluorescein diacetate （DCFH-DA） and mitochondrial membrane potential with JC-1 assay. The nuclear morphology was observed based on Hoechst 33342 staining， and apoptosis was examined by flow cytometry combined with Annexin V-FITC/PI staining. ResultThe viability of the cells was highest in the presence of the extract of the two medicinals mixed at the ratio of 2∶1. Compared with normal control group， OGD/R group showed damaged cell morphology， high release rate of LDH and levels of ROS and MDA （P<0.01）， low SOD activity and GSH level （P<0.01）， low mitochondrial membrane potential， and high apoptosis rate （P<0.01）. Compared with OGD/R group， SP extract improved cell viability and cell morphology and reduce cell LDH release rate in a concentration-dependent manner （P<0.01）. In addition， SP extract at 30， 100 mg·L-1 reduced the level of intracellular ROS and increased SOD activity and GSH level （P<0.05， P<0.01）， and SP extract at 100 mg·L-1 decreased the content of MDA （P <0.05）. Moreover， SP extract increased mitochondrial membrane potential， and SP extract at 30， 100 mg·L-1 lowered the apoptosis rate （P<0.01）. ConclusionThe extract of Salvia miltiorrhiza Bunge and Radix Puerariae mixed at 2∶1 shows better protective effect on OGD/R-injured SH-SY5Y cells. The mechanism is the likelihood that it alleviates oxidative damage of cells and inhibits cell apoptosis.

Protective Effect of Salviae Miltiorrhizae Radix et Rhizoma and Puerariae Lobatae Radix Extract on SH-SY5Y Cells Injured by Oxygen-glucose Deprivation/Reoxygenation / 中国实验方剂学杂志

ObjectiveTo explore the protective effect of Salviae Miltiorrhizae Radix et Rhizoma and Puerariae Lobatae Radix （SP） extract on oxygen-glucose deprivation/reoxygenation （OGD/R）-injured SH-SY5Y cells based on oxidative stress and apoptosis. MethodThe extracts of the two medicinal materials mixed in different ratios were prepared. Human neuroblastoma SH-SY5Y cells were cultured in vitro and the injury was induced by OGD/R. Cell counting kit-8 （CCK-8） assay was used to screen the optimal ratio of the two medicinals and then the extract was used for further experiment. SH-SY5Y cells were classified into normal control group， OGD/R group， and low-， medium-， and high-dose SP （2∶1） extract groups （10， 30， 100 mg·L-1， respectively）. Cells in the groups， except the normal control group， were rapidly reoxygenated for 12 h after 4 h OGD for modeling. Then cell viability was detected by CCK-8 and cell morphology was observed under the microscope. The release rate of lactate dehydrogenase （LDH）， superoxide dismutase （SOD） activity， and content of glutathione （GSH） and malondialdehyde （MDA） were determined by spectrophotometry. The level of reactive oxygen species （ROS） was detected with 2，7-dichlorodihydrofluorescein diacetate （DCFH-DA） and mitochondrial membrane potential with JC-1 assay. The nuclear morphology was observed based on Hoechst 33342 staining， and apoptosis was examined by flow cytometry combined with Annexin V-FITC/PI staining. ResultThe viability of the cells was highest in the presence of the extract of the two medicinals mixed at the ratio of 2∶1. Compared with normal control group， OGD/R group showed damaged cell morphology， high release rate of LDH and levels of ROS and MDA （P<0.01）， low SOD activity and GSH level （P<0.01）， low mitochondrial membrane potential， and high apoptosis rate （P<0.01）. Compared with OGD/R group， SP extract improved cell viability and cell morphology and reduce cell LDH release rate in a concentration-dependent manner （P<0.01）. In addition， SP extract at 30， 100 mg·L-1 reduced the level of intracellular ROS and increased SOD activity and GSH level （P<0.05， P<0.01）， and SP extract at 100 mg·L-1 decreased the content of MDA （P <0.05）. Moreover， SP extract increased mitochondrial membrane potential， and SP extract at 30， 100 mg·L-1 lowered the apoptosis rate （P<0.01）. ConclusionThe extract of Salvia miltiorrhiza Bunge and Radix Puerariae mixed at 2∶1 shows better protective effect on OGD/R-injured SH-SY5Y cells. The mechanism is the likelihood that it alleviates oxidative damage of cells and inhibits cell apoptosis.

Buyang Huanwutang Promoted Proliferation and Differentiation of Neural Stem Cells via Regulating Autophagy Following Oxygen-glucose Deprivation/Reoxygenation Injury / 中国实验方剂学杂志

Objective:To investigate the effect of Buyang Huanwutang （BHT） on proliferation and differentiation in neural stem cells （NSCs） after oxygen-glucose deprivation/reoxygenation （OGD/R） injury. Method:NSCs isolated from the hippocampus of SD rats were cultured and randomly divided into a normoxia group， a model group， a BHT group， a rapamycin （Rapa） group， and a combination group ［autophagy inhibitor 3-methyladenine （3-MA） combined with BHT］. The 20% blank serum was used in the normoxia group， and 20% BHT-medicated serum in the BHT group. The doses of Rapa and 3-MA were 1 μmol·L^-1 and 5 mmol·L^-1， respectively. The cells were subjected to OGD/R except those in the normoxia group. The cell morphology was observed under a light microscope. NSCs were confirmed by immunofluorescence detection of nestin expression. The viability and proliferation of NSCs were assessed by cell counting kit-8 （CCK-8） assay and 5-ethynyl-2-deoxyuridine （EdU） labeling， respectively. Furthermore， Ad-mCherry-GFP-LC3B fluorescence assay was performed to investigate autophagy. The effect of BHT on autophagy-related protein expression was detected by western blot assay. Brain derived neurotrophic factor （BDNF）， <italic>β</italic>-tubulin Ⅲ， and glial fibrillary acidic protein （GFAP） were evaluated by immunofluorescence assay. Result:OGD/R significantly reduced the cell viability of rat NSCs as compared with the normoxia group. Compared with the model group， the BHT group exhibited significantly improved viability of rat NSCs （<italic>P</italic><0.01）. BHT induced the production of autophagosomes in NSCs after OGD. The BHT group showed increased expression of microtuble-associated protein 1 light chain 3Ⅱ (LC3Ⅱ） and Beclin-1 （<italic>P</italic><0.05，<italic>P</italic><0.01） and slightly changed p62 compared with the normoxia group， and significantly up-regulated LC3Ⅱ and Beclin-1 （<italic>P</italic><0.05，<italic>P</italic><0.01） and down-regulated expression of p62 （<italic>P</italic><0.01） compared with the model group. The Rapa group had similar effect as the BHT group （<italic>P</italic><0.05，<italic>P</italic><0.01）， while the combination group inhibited the activity of autophagy （<italic>P</italic><0.01）. As indicated by the results of ad-mCherry-GFP-LC3B， compared with the normoxia group， the model group showed increased fluorescence intensity （<italic>P</italic><0.01）， and the BHT and Rapa groups could further increased the fluorescence intensity of autophagy （<italic>P</italic><0.01）， while the combination group inhibited autophagy activity （<italic>P</italic><0.01）. Immunofluorescence results revealed that compared with the normoxia group， the model group displayed significantly reduced positive cells of EdU， <italic>β</italic>-tubulin Ⅲ， GFAP， and BDNF （<italic>P</italic><0.01）， and the BHT and Rapa groups exerted similar protective and promoting effects （<italic>P</italic><0.05，<italic>P</italic><0.01）， while the combination group partially blocked the neuroprotection and differentiation ability of BHT （<italic>P</italic><0.05）. Conclusion:BHT pretreatment can effectively protect rat NSCs against OGD-induced injury and promoted proliferation and differentiation by up-regulating autophagy.

LncRNA MALAT1 aggravates oxygen-glucose deprivation/reoxygenation-induced neuronal endoplasmic reticulum stress and apoptosis via the miR-195a-5p/HMGA1 axis

BACKGROUND: This study aimed to investigate the potential role and molecular mechanism of lncRNA metastasis associated lung adenocarcinoma transcript 1 (MALAT1) in cerebral ischemia/reperfusion injury. RESULTS: Using an oxygen-glucose deprivation/reoxygenation (OGD/R) cell model, we determined that the expression of MALAT1 was significantly increased during OGD/R. MALAT1 knockdown reversed OGD/R-induced apoptosis and ER stress. Mechanistically, MALAT1 promoted OGD/R-induced neuronal injury through sponging miR-195a-5p to upregulating high mobility group AT-hook1 (HMGA1). CONCLUSIONS: Collectively, these data demonstrate the mechanism underlying the invovlvement of MALAT1 in cerebral ischemia/reperfusion injury, thus providing translational evidence that MALAT1 may serve as a novel biomarker and therapeutic target for ischemic stroke.

Protective Effect of Cerebrospinal Fluid Containing Tongqiao Huoxuetang on Brain Microvascular Endothelial Cells from Rats with Oxygen Glucose Deprivation/Reoxygenation Injury / 中国实验方剂学杂志

Objective:To investigate the protective effect of cerebrospinal fluid containing Tongqiao Huoxuetang (TQHXT) on oxygen-glucose deprivation/reoxygenation (OGD/R)-induced brain microvascular endothelial cells (BMECs), in order to explore the underlying mechanisms. Method:Primary BMECs were extracted by enzymatic digestion, and the cells were randomly divided into six groups: the normal control group, the OGD/R group, the TQHXT group（20%）, the nimodipine（NMDP） group (10 μmol·L-1), the cabozanix group (1 μmol·L-1) and the combination group. Except for the normal control group, the cells in the other groups were rapidly reoxygenated for 24 h after 2 h of oxygen-glucose deprivation, the OGD/R modeling was performed, and the rats were administered with drugs by groups. BMECs were identified by cell immunofluorescence staining, morphological and ultrastructural changes of OGD/R-induced BMECs were observed, and changes in cell transmembrane resistance (TEER) were detected. The levels of nitric oxide (NO), the activity of lactate dehydrogenase (LDH), the fluorescence intensity of reactive oxygen species (ROS) and the content of tissue-type plasminogen activator (tPA) were measured with kits. Intracellular Ca2+ concentration and cell apoptosis were detected by flow cytometry, and the expression of CD34 was observed. The protein expressions of zonula occluden-1 (ZO-1), vascular endothelial growth factor (VEGF), adhesion kinase (FAK), and Paxillin were detected by Western blot. Result:Compared with the normal control group, the cells in the OGD/R group were shrinking and rounded, TEER value and ZO-1 protein expression in cells were significantly decreased, the contents of NO, LDH and ROS in cells were significantly increased, the content of tPA was significantly decreased, the concentration of Ca2+ and the apoptosis in the cells were significantly increased, CD34 was expressed in cells, and the protein expressions of VEGF, FAK and Paxillin were significantly increased (P<0.01). Compared with the OGD/R group, cell damage in the TQHXT group was significantly improved, the TEER value and ZO-1 protein expression in cells were significantly increased, the contents of NO, LDH and ROS in cells were significantly reduced, the content of tPA was significantly increased, the concentration of Ca2+ and the apoptosis in the cells were significantly reduced, CD34 expression increased in cells, and the protein expressions of VEGF, FAK and Paxillin were significantly increased (P<0.05，P<0.01). Conclusion:CSF containing TQHXT protects BMECs from OGD/R injury possibly by promoting angiogenesis through the VEGF-VEGFR2/FAK/Paxillin signaling pathway.

Study of astragaloside IV alleviating oxidatIVe stress injury of pc12 cells induced by oxygen-glucose deprIVation/reoxygenation through regulating autophagy / 中国药理学通报

Aim To observe the effects of astragaloside IV on autophagy and oxidative stress induced by oxy gen-glucose deprivation/reoxygenation in PCI2 cells. Methods PCI2 cells were divided into normal group, model group (ox-ygen-glucose deprivation/reoxygenation group) , astragaloside IV group, and autophagy inhibitor + astragaloside IV group. CCK-8 was used to detect cell viability, and ELISA to detect MDA, SOD and GSH-Px. Transmission electron microscope and MDC fluorescent staining were employed to observe the changes of au-tophagosome, and Western blot to detect the protein expression of Beclinl. Results Compared with normal group, the cell activity in model group decreased (P <0.05), MDA content increased, SOD and CSH-Px activity decreased (P < 0.05), and autophagosomes could be seen and the protein expression of Beclinl increased ( P < 0.05). Compared with model group, the cell activity in astragaloside IV group increased ( P < 0. 05), MDA content decreased, SOD and GSH-Px activity increased (P < 0.05), the number of autophagosomes and the protein expression of Beclinl increased (P<0.05). When autophagy inhibitor was given at the same time, the autophagy inhibitor could obviously antagonize the antioxidant effect of astragaloside IV while alleviating autophagy. Conclusions Astragaloside IV can protect PC 12 cells from oxidative stress injury induced by oxygen-glucose deprivation/reoxygenation by up-regulating autophagy.

Inhibitory effect of exosomes secreted by human umbilical cord mesenchymal stem cells on apoptosis of oxygen-glucose deprived reoxygenation model of venous endothelial cells / 中华行为医学与脑科学杂志

Objective@#To explore the inhibitory effect of exosomes secreted by human umbilical cord mesenchymal stem cells(HUCMSC) on apoptosis of human umbilical vein endothelial cells(HUVEC) after model group(oxygen-glucose deprivation reoxygenation), and to clarify its possible mechanism.@*Methods@#Human umbilical cord mesenchymal stem cells were cultured. The collected cell supernatant was stored in a centrifugal tube. The exosomes secreted by human umbilical cord mesenchymal stem cells were extracted by ultracentrifugation and identified. Human umbilical vein endothelial cells were randomly divided into control group, model group and different concentrations of HUCMSC-EXO(20 μg/ml, 40 μg/ml, 60 μg/ml) treatment groups(adding HUCMSC-EXO into the model group) . The morphological changes of HUVEC cells in each group were observed by inverted phase contrast microscope, and the proliferation inhibition rate of HUVEC in each group was measured by CCK-8 reagent. Western blot was used to detect the expression of apoptosis-related proteins Caspase-3, Bax, Bcl-2 and hypoxia-associated protein hypoxia inducible factor 1α(HIF-1α). Inhibitor(HIF-1α inhibitor) + model group and HUCMSC-EXO + inhibitor + model group were added on the basis of the above experiments. Western blot analysis was performed to observe the effects of HUCMSC-EXO, inhibitor and both of them on HIF-1α and Bax expressions in HUVEC.@*Results@#HUCMSC-EXO was successfully extracted and identified. Compared with the control group, the volume of HUVEC in the model group and the HUCMSC-EXO group with different concentrations decreased, became round, connected and evacuated, and the growth state was poor under the inverted phase contrast microscope.CCK-8 detection showed that the cell viability in the HUCMSC-EXO group was significantly higher than that in the model group, the difference was statistically significant (t=9.23, P<0.05). Western blot analysis showed that compared with the control group, the expression levels of Caspase-3 ((0.296±0.038), (0.879±0.088); t=14.92, P<0.05), Bax((0.234±0.034), (0.762±0.084); t=14.36, P<0.05) of HUVEC in the model group were up-regulated, and the expression level of Bcl-2 was down-regulated ((0.863±0.103), (0.387±0.059); t=9.85, P<0.05), with statistically significant differences. Compared with the model group, the expression levels of Caspase-3( (0.586±0.075); t=6.24, P<0.05), Bax((0.311±0.055); t=11.01, P<0.05) and Bcl-2((0.665±0.071); t=7.45, P<0.05) of HUVEC in the HUCMSC-EXO treatment group were down-regulated and the differences were statistically significant. Inhibitor intervention experiments showed that there were no significant differences between the inhibitor+ model group and HUCMSC-EXO+ inhibitor+ model group in the expression of HIF-1α protein ((0.348±0.055), (0.388±0.077); t=1.04, P>0.05)and Bax protein ((0.363±0.069), (0.370±0.064); t=0.18, P>0.05). But both of them were down-regulated compared with the model group (HIF-1α protein (0.919±0.064), Bax protein (0.902±0.071)), the differences were significant( t=13.56, t=13.03, both P<0.05).@*Conclusion@#HUCMSC-EXO has a protective effect on OGD/R model of HUVEC, and its mechanism may be related to the down-regulation of HIF-1α expression.

Effect of Longxuetongluo capsule in protecting vascular endothelial cells against oxygen-glucose deprivation/reoxygenation-induced apoptosis / 中国中药杂志

Focal cerebral ischemia reperfusion is an essential process during ischemic stroke. The apoptosis of vascular endothelial cells induced by ischemia/reperfusion (I/R) injury is an important cause for brain injury after focal cerebral ischemia. Longxuetongluo capsule (LTC) has been used for the treatment of ischemic stroke in clinic. However, its underlying action mechanism is still unclear. This study aimed to verify the protective effect and mechanisms of LTC on HUVEC cells against oxygen-glucose deprivation/reoxygenation (OGD/R) injury through MTT, LDH, flow cytometry, AO/EB staining and western blot assays. As a result, OGD/R significantly decreased the viability of HUVEC cells, which was significantly improved by LTC. LDH release assay showed that OGD/R significantly increased the lactate dehydrogenase (LDH) release, and LTC dramatically reduced the OGD/R-induced LDH release. Further mechanism study indicated that LTC dose-dependently inhibited the cleavage of PARP, caspase 3, and caspase 9 induced by OGD/R, suggesting that LTC could inhibit the activation of caspase 3/9 apoptosis pathway in the OGD/R-induced apoptosis of HUVEC cells. In conclusion, LTC could protect HUVEC cells against OGD/R injury by inhibiting the activation of mitochondria-related caspase 3/9 apoptosis pathway.

Xueshuantong capsule alleviates oxygen-glucose deprivation/reoxygenation-induced tight junction damage of HUVEC cells / 中国比较医学杂志

Objective To study the protective effect of Panax notoginseng saponins(PNS)and its components Rg1 and Rb1 on oxygen-glucose deprivation/reoxygenation(OGD/Reox)-induced tight junction damage. Methods Anaerobic box were used to induce OGD in HUVEC cells for 6 h followed by reoxygenation for 24 h. Transepithelial/endothelial electrical resistance(TEER)and cell permeability were detected,immunefluorescence was used to observe the ZO-1 and claudin-5 protein expression. Results PNS 20,40 mg/L and ginsenoside Rb1 significantly inhibited the OGD/Reox-induced decreased tight junction resistance,and the increased cell permeability(P< 0.05). PNS 20,40 mg/L and ginsenoside Rb1 partly restored the inter-cellular tight junctions which were regularly arranged on the cell membrane, and the cells displayed cobble stone-like arrangement. Conclusions PNS ameliorates ischemia-induced vascular endothelial cell tight junction damage via MMP-9 and VEGF/VEGFR2 signaling pathway. Rb1 is one of the effective monomer components.

Over-expression of PGC-1α reverses mitochondrial function reduction and apoptosis in OGD/R-induced neurons / 中国病理生理杂志

AIM:To investigate the effect of over-expression of peroxisome proliferator-activated receptor γ co-activator-1α (PGC-1α) on mitochondrial morphology and cell apoptosis in the cortical neurons with oxygen glucose depriva-tion/reoxygenation(OGD/R). METHODS:The whole gene sequence of PGC-1α was obtained from the cerebral cortex of C57BL/6 mice by RT-PCR and cloned into the eukaryotic expression vector pEGFP-N1. The pEGFP-N1-PGC-1α was iden-tified by PCR,and transfected into cortical neurons. The level of PGC-1α expression was identified by Western blot. The cortical neurons transfected with pEGFP-N1 and pEGFP-N1-PGC-1α vectors were treated with OGD/R. The mitochondrial mass,reactive oxygen species (ROS) and ATP production,cell apoptosis and changes of cleaved caspase-3 were detected by MitoTracker Red staining,flow cytometry,ATP metabolic assay kit and TUNEL. RESULTS:Over-expression of PGC-1α inhibited the decrease in mitochondrial biogenesis capacity and the ROS formation of OGD/R neurons(P<0.05),en-hanced the ability of ATP synthesis (P<0.01),inhibited neuronal apoptosis (P<0.01) and decreased the activation of caspase-3 (P<0.01). CONCLUSION:PGC-1α over-expression inhibits neuronal apoptosis with OGD/R treatment by promoting mitochondrial biogenesis,inhibiting the production of ROS and maintaining mitochondrial function. PGC-1α may be used as a target for the development of cerebral ischemia/reperfusion injury drugs.

Protective effect of notoginsenoside R1 on neuron injury induced by OGD/R through ATF6/Akt signaling pathway / 中国中药杂志

Notoginsenoside R1(NGR1),a critical compound in traditional herb Panax notoginseng, is a kind of estrogen receptor agonist.It is reported to exhibit anti-apoptotic,anti-oxidative and anti-inflammatory properties activity, so it is widely used for treatment of various diseases.In order to investigate the potential neuroprotective effect of NGR1 in hypoxic-ischemic brain damage(HIBD), primary cortical neurons were used in this study to establish oxygen-glucose deprivation/reoxygenation(OGD/R) injury models. They were treated with NGR1 and estrogen receptor inhibitor ICI-182780 respectively, then the neuronal survival, cell membrane integrity and apoptosis were assessed by MTT assay,lactate dehydrogenase test(LDH) and Hoechst 33342 stain respectively, while the protein expression levels of ATF6α,p-Akt,Akt,Bax and Cleaved Caspase-3 were measured by Western blotting. Results indicated that as compared with the blank control group,OGD/R could induce cell injury and apoptosis(P<0.05), reduce relative integrity of cell membrane(P<0.05), decrease protein expression of ATF6α,p-Akt(P<0.05), and increase protein expression of Bax and Cleaved Caspase-3(P<0.05) in the primary cortical cells. After NGR1 treatment, the expression levels of ATF6α,p-Akt were obviously increased, and the expression levels of Bax and Cleaved Caspase-3 and the apoptosis of neuron were decreased(P<0.05). However, these neuroprotective properties of NGR1 against ODG/R-induced cell damage could be blocked by ICI-182780. This finding indicated that NGR1 may protect the primary cortical neurons against OGD/R induced injury,and the mechanism may be associated with accelerating the activation of the ATF6/Akt signaling pathway via estrogen receptors.

The protective effect of tetramethylpyrazine on rat myocytes with transient oxygen-glucose deprivation followed by reoxygenation injury and mechanism study / 中国生化药物杂志

Objective This study explored the protective effect of tetramethylpyrazine on myocardial ischemia/reperfusion injury via inhibiting oxidative stress. Methods Primary cultured neonatal myocytes were applied to explore the anti-ischemia/reperfusion injury property in vitro. The survival viability of myocytes was determined by MTT; enzyme activities such as lactate dehydrogenase, creatine kinase, superoxide dismutase, malondialdehyde, and nitric oxide were analyzed with assay kits; inducible nitricoxide synthase and endothelial nitric oxide synthase expressions were determined by Westernblot. Results Tetramethylpyrazine significantly improved the beating frequencies of myocytes after oxygen-glucose deprivation/reoxygenation procedure, decreased lactate dehydrogenase, creatine kinase, and malondialdehyde levels and enhanced superoxide dismutase activity.Tetramethylpyrazine also inhibited excessive production of nitric oxide through downregulating inducible nitric oxide synthase as well as upregulating endothelial nitric oxide synthase during ischemia/reperfusion injury. Conclusion Tetramethylpyrazine could significantly improve the oxidative-stress tolerance of myocytes to keep cell membrane integrity and protect the myocardial tissue of normal physiological function via an antioxidant effect and by restoring the balance between inducible nitric oxide synthase and endothelial nitric oxide synthase, while inhibiting the generation of cytotoxic concentrations of NO.

Effect of CREB-shRNA on mitochondrial morphology and cell apoptosis in OGD/R-induced cortical neurons / 中国病理生理杂志

AIM: To construct recombinant lentiviral vector with short hairpin RNA (shRNA) of CREB gene, and to investigate the effect of CREB gene silencing on mitochondrial morphology and cell apoptosis in oxygen-glucose deprivation/reoxygenation (OGD/R)-induced cortical neurons.METHODS: Three lentiviral vectors pLentiLox3.7 (PLL) inserted shRNA fragments targeting CREB gene were co-transfected with the packaging plasmids psPAX2 and pMD2.G to the 293T cells, and the virus particles, which was infected with the primary cortical neurons, was encapsulated.The protein expression of CREB was detected by Western blot.The mitochondrial morphology, cell apoptosis and the expression of Bcl-2 and Bax were evaluated by the methods of MitoTracker red, TUNEL and Western blot in OGD/R induced cortical neurons after CREB gene silencing.RESULTS: The pLL-CREB-shRNA1 was the most effective shRNA, which inhibited 80% CREB gene expression in the cortical neurons.The mitochondrial was appeared dot and fragment morphology in OGD/R induced cortical neurons with transfected pLL-CREB-shRNA1 plasmid.In addition, the expression of Bcl-2 was decreased, the expression of Bax, and the apoptosis of the neurons were increased by tranfected with pLL-CREB-shRNA1.CONCLUSION: CREB shRNA recombinant lentiviral vector specifically inhibits the expression of CREB gene.CREB gene silencing promotes the cell apoptosis and mitochondrial morphological changes in the cortical neurons induced by OGD/R.

Effects of resveratrol pretreatment on neurite growth of primary cortical neurons after oxygen-glucose deprivation/reperfusion injury in rats / 解剖学报

Objective To investigate the effects of resveratrol pretreatment on neurite growth of rat primary cortical neurons after oxygen-glucose deprivation/reperfusion (OGD/R) injury in vitro. Methods Primary cortical neurons were cultured under oxygen and glucose deprivation for 150 minutes and reoxygenation for 24 hours. The study had the normal, control and 5μmol/L resveratrol pretreatment groups. Neurons were identified with immunofluorescence. Cell viability was detected with cell counting kit-8(CCK-8) assay. Cell apoptosis was detected with TUNEL assay. Immunofluorescence and Western blotting measured the expressions of microtubule-associated protein 2(MAP-2) and growth associated protein 43 (GAP-43), and the length and number of neurites were counted. Results Cells had high expression of neuronal specific marker MAP-2. Compared with the control group, resveratrol treatment significantly enhanced the neurons viability (0.551±0.009 vs 0.436±0.013, P<0.01), decreased the numbers of apoptosis (18.3% ±1.3% vs 35.3% ±1.9%, P<0.01), upregulated the expressions of MAP-2 (0.790 ± 0.102 vs 0.462 ±0.063, P <0.01) and GAP-43 (0.768 ± 0.084 vs 0.424 ±0.065, P< 0.01) proteins, increased the length (89.510 ± 6.939 vs 61.538 ± 9.14, P < 0.01) and numbers (6.347 ± 1.002 vs 3.040 ± 0.608, P < 0.01) of neurites. Conclusion Resveratrol pretreatment can reduce injury and promote neurite growth of cultured neurons after OGD/R.

Effects of inhibiting shh signaling pathway with cyclopamine pretreatment on proliferation of cortical neural stem cells after oxygen-glucose deprivation/reoxygenation injury in rats / 中国药学杂志

OBJECTIVE: To investigate the effect of inhibitting sonic hedgehog (Shh) signaling pathway with cyclopamine pretreatment on proliferation of rat cortical neural stem cells (NSCs) after oxygen-glucose deprivation/reoxygenation (OGD/R) injury in vitro. METHODS: The suspended culture was used for the isolation and purification of NSCs in neonatal Sprague-Dawley (SD) rats. The third passage NSCs for adherent culture were deprived oxygen and glucose for 150 min and recovered oxygen and glucose for 24 h. There were three groups, including normal, model and cyclopamine pretreatment groups. NSCs were identified with immunofluorescence. CCK-8 assay was used to examine cell viability. The proliferation of NSCs was measured with BrdU assay and flow cytometry cell cycle. Western blot was used to detect the protein expressions of Ptc-1, Smo and Gli-1. RESULTS: There were high expression of nestin protein in suspended and adherent cultured cells. The cell vitalities in model and cyclopamine groups were decreased significantly compared with the normal group. Especially, there was less cell vitality in cyclopamine group (P<0.05). There was significantly increased for NSCs proliferation and upregulated for Ptc-1,Smo and Gli-1 proteins in the model group. On the contrary, compared with the model group, NSCs proliferation and the expressions of Ptc-1, Smo and Gli-1 proteins in cyclopamine group were significantly decreased (P<0.05). CONCLUSION: Cyclopamine pretreatment can inhibit NSCs proliferation after OGD/R injury. The result suggests that Shh signaling may participate in the regulation of NSCs proliferation after injury.

Effects of tetramethylpyrazine-2′-O-sodium ferulate on swelling of astrocytes and expression of AQP4 after oxygen-glucose deprivation/reoxygenation / 中国药理学通报

Aim To explore the effects of tetrameth-ylpyrazine-2′-O-sodium ferulate (TSF)on the swelling of astrocytes and the expression of AQP4 after oxygen gl-ucose deprivatio /reoxygenation(OGD /Reox).Methods Astrocytes were divided into 4 groups:control group, OGD /Reox group,Ozagrel group and TSF group.The effects of TSF on astrocytes were investigated 6,1 2,24 and 48 h after OGD /Reox.The cell injury was assessed by measuring LDH activity and MTT.The expression levels of AQP4 protein of astrocytes were detected u-sing Western blot.Results OGD /Reox induced obvi-ous cell swelling and significant reduction of LDH in astrocytes whereas TSF remarkably attenuated OGD-in-duced astrocyte swelling and LDH reduction (P group(P 0.05 ).Conclusion TSF can attenuate OGD-induced swelling of astrocytes through decreasing the AQP4 expression.

Effects of hydrogen sulfide on mouse cortical neuronal injuries induced by oxygen gloucose deprivation/reoxygenation in vitro / 解剖学报

Objective To explore the effects of H 2 S on neuronal injuries induced by oxygen glucose deprivation /reoxygenation ( OGD/R) in cortical neurons .Methods For OGD, the primary cultured cortical neurons were incubated with glucose-free EBSS media for 4h in N2/CO2/O2 (93%/5%/2%) atmosphere.Thereafter, the media were replaced by Neurobasal/B27 culture media and the neurons were incubated for 12 h in a 5%CO2 incubator at 37℃.NaHS was used as a H2S donor and cell survival rate was determined by cell counting kit 8(CCk-8).[Ca2+]i was determined using fura-2/AM and fluorescence microscopic imaging systems .The release rate of lactate dehydrogenase ( LDH) was determined by lactate dehydrogenase assay kit , and cell damage was analyzed by staining of propidium iodide ( PI ) .Results After pretreated with 200, 300 and 600μmol/L sodium hydrosulfide ( NaHS) for 30min before OGD/R, the cell survival rate of neurons significantly increased (n=4).[Ca2+]I(n=5), LDH release rate (n=4) and cell damage percentage (n=6) in the neuron pretreated with 300 μM NaHS were significantly lower than those in ODG/R cells.Treatment with 10μmol/L calcium chelator BAPTA also reduced the LDH release rate and cell damage percentage induced by ODG /R in neurons . Conclusion The results indicate that H 2 S may inhibit the OGD/R induced damage in cortical neurons via reducing calcium overload of neurons .

Protective effect of HMGB1 gene silence on astrocyte injury caused by oxygen-glucose deprivation/reoxygenation / 解放军医学杂志

Objective To investigate the protective effect of high mobility group box 1 (HMGB1) gene silence on astrocyte injury caused by oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro. Methods Astrocytes were divided into control group, OGD/R group and HMGB1 siRNA group. Astrocytes in OGD/R group were cultured with glucose free DMEM under 1% O2 condition, then they were treated with OGD for 2, 4 and 6h respectively, and then reoxygenated for 24h. In HMGB1 siRNA group, astrocytes that transfected with HMGB1 small interference RNA (siRNA) lentivirus-vector were treated with OGD 6h, and then reoxygenated for 24h. After 24h reoxygenation, the mRNA and protein expression of HMGB1 in the astrocytes were determined by RT-PCR and Western blotting. HMGB1 protein in culture supernatant of astrocytes was determined by ELISA. The cell injury and survival rate were assessed by LDH activity (LDH%) and MTT assay. Results Compared with the astrocytes without transfection of HMGB1 siRNA lentivirus-vector, the protein expression of HMGB1 was suppressed by siRNA. Compared with the control group, with prolongation of the OGD time, the mRNA and protein expression of HMGB1 increased gradually (P<0.05) after OGD/R, and it further increased with elapse of time. OGD resulted in significant injuries with time extention, and the LDH% increased (P<0.05) with marked lowering of survival rate (P<0.05). Compared with the OGD/R group, cell injury in HMGB1 siRNA group alleviated remarkably, and survival rate was elevated significantly (P<0.01). Conclusion The expression of HMGB1 in astrocytes can be inhibited by siRNA, and over-expression of HMGB1 might be an important factor in OGD/R-induced cell injury.