MiR-181c对人脑胶质瘤细胞增殖及凋亡的作用

目的观察miR-181c对人脑胶质瘤细胞增殖及凋亡的影响,进一步探讨miR-181c的生物学功能。方法化学合成miR-181c,脂质体转染U251细胞。应用cck-8法和流式细胞术检测细胞的增殖和凋亡。结果miR-181c上调后对U251细胞具有抑制作用,且呈明显的剂量依赖性,而对照组无明显抑制作用。结论化学合成的miR-181c在人脑胶质瘤细胞增殖和凋亡过程中发挥重要作用,可能成为胶质瘤基因治疗的新靶点。     

Role and mechanism of microRNA-21 in H2O2-induced apoptosis in bone marrow mesenchymal stem cells

microRNA-21 (miR-21) contributes to anti-apoptosis, proliferation and migration in many cells, but its role in inhibiting apoptosis in bone marrow mesenchymal stem cells (BMSC) remains unclear. The aim of this study was to determine the role of miR-21 in H₂O₂-induced BMSC apoptosis. We used quantitative real time-polymerase chain reaction (RT-PCR) to demonstrate the level of miR-21 after treatment of BMSC with H₂O₂. BMSC apoptosis was induced by different concentrations of H₂O₂ and was decreased in miR-21-upregulated cells. The expression of PTEN, a functional target gene of miR-21 in BMSC, was regulated by miR-21. The RT-PCR results indicated that miR-21 was significantly up-regulated, and western blot analysis indicated that Bcl-2 was up-regulated, whereas the apoptosis-related genes caspase 3/9 and Bax were down-regulated in miR-21-up-regulated cells. The miR-21-up-regulated cells had significantly enhanced Akt phosphorylation, as measured by western blot analysis. LY294002, an inhibitor of Akt activation, abolished the protective effects of miR-21-up-regulated cells. These results suggest that miR-21 contributes to inhibition of apoptosis in BMSC by down-regulating PTEN, potentially via the PI3K/Akt pathway.     

长链非编码RNA MALAT1对神经母细胞瘤系细胞生物学特性的影响

目的 探讨长链非编码RNA MALAT1对神经母细胞瘤系细胞生物学特性的影响及作用机制。方法 体外培养神经母细胞瘤系SHEP2细胞，细胞分为Control、sh-MALAT1、miR-181a-5p inhibitor和sh-MALAT1+ miR-181a-5p inhibitor组，其中sh-MALAT1组转染sh-MALAT1，miR-181a-5p inhibitor组转染miR-181a-5p inhibitor，sh-MALAT1+inhibitor组共同转染sh-MALAT1与miR-181a-5p inhibitor，Control组加入等量空载体。PCR检测mRNA水平；生物信息预测MALAT1与miR-181a-5p的靶向关系，荧光素酶实验鉴定；CCK8法检测细胞增殖能力；Hoechst法检测细胞凋亡；划痕实验测试细胞迁移；Transwell实验检测细胞侵袭；免疫印迹法检测蛋白表达。结果 sh-MALAT1明显降低MALAT1并提高miR-181a-5p在神经母细胞瘤细胞系SHEP2细胞mRNA水平。miR-181a-5p mimic明显降低MALAT1 wt荧光素酶活性。sh-MALAT1抑制SHEP2细胞增殖、侵袭及迁移，促进细胞凋亡；miR-181a-5p inhibitor促进细胞增殖、侵袭及迁移，抑制细胞凋亡，并减弱sh-MALAT1产生的影响。同时，sh-MALAT1抑制PI3K/Akt信号通路，而miR-181a-5p inhibitor可激活此信号通路并减弱sh-MALAT1的抑制作用。结论 MALAT1靶向下调miR-181a-5p表达促进神经母细胞瘤细胞系SHEP2细胞增殖、迁移和侵袭。     

miR-181a和miR-181b抑制胶质瘤细胞的增殖和侵袭

目的 探讨miR-181a和miR-181b对胶质瘤细胞增殖和侵袭等影响.方法 通过实时荧光定量PCR检测miR-181a和miR-181b在胶质瘤组织和细胞株中的表达情况.我们合成miR-181a和miR-181b寡聚核苷酸及构建pre-miR-181a和pre-miR-181b表达载体,转染胶质瘤细胞,通过MTT、Transwell实验、流式检测和软琼脂实验,观察上调miR-181a和miR-181b表达后对胶质瘤细胞增殖、侵袭、转化能力和细胞凋亡的影响.结果 miR-181a和miR-181b在胶质瘤组织和细胞株较正常脑组织均呈过低表达;miR-181a表达水平与胶质瘤等级呈负相关.上调miR-181a和miR-181b表达能有效抑制胶质瘤细胞生长,降低其转化和侵袭能力,诱导凋亡.结论 胶质瘤中异常低表达的miR-181a和miR-181b可能发挥着肿瘤抑制因子作用.     

当归含药血清通过调控miR-129表达对阿尔茨海默病细胞模型的保护作用

目的 探讨当归含药血清通过调控微小RNA-129(MicroRNA-129,miR-129)表达对阿尔茨海默病PC12细胞的保护作用。方法 分别以1.5 g/kg当归药液及等量生理盐水对SD(Sprague Dawley)大鼠灌胃处理,配制成10%含药血清及正常血清培养液; 将PC12细胞分为空白组、模型组、药物组、药物+Control小干扰RNA(Small interference RNA,siRNA)组、药物+miR-129 siRNA组,除空白组外,其余各组均用30 μL的Aβ_25-35溶液诱导细胞损伤24 h构建阿尔茨海默病(Alzheimer’s disease,AD)细胞模型,空白组及模型组用空白血清培养液培养,其余各组用10%含药血清培养液培养,培养48 h后收集各组细胞观察细胞形态学; 实时荧光定量聚合酶链反应(Quantitative real-time polymerase chain reaction,qRT-PCR)法检测其中miR-129表达水平,采用甲基噻唑蓝(Methyl thiazolyl tetrazolium,MTT)法检测各组细胞的增殖抑制率; 流式细胞仪检测各组细胞的凋亡及周期情况; 蛋白免疫印迹(Western blot,WB)检测细胞凋亡相关因子蛋白的表达水平; 酶联免疫吸附(Enzyme-linked immunoSorbent assay,ELISA)试剂盒检测乳酸脱氢酶(Lactate dehydrogenase,LDH)、丙二醛(Malondialdehyde,MDA)、超氧化物歧化酶(T-superoxide dismutase,T-SOD)水平。结果 与空白组比较,模型组PC12细胞贴壁功能受损,miR-129、B淋巴细胞瘤-2(B-cell lymphoma-2,Bcl-2)蛋白水平、S期及G2/M期细胞数目、T-SOD水平降低(P<0.05),细胞抑制率、凋亡率、半胱氨酸蛋白酶-3(Cysteinyl aspartate specific proteinase,Caspase-3)、Bcl-2相关X蛋白(Bcl-2 associated X protein,Bax),G0/G1期细胞数目、LDH,MDA水平升高(P<0.05); 与模型组比较,药物组细胞贴壁功能改善,miR-129,Bcl-2蛋白水平、S期及G2/M期细胞数目、T-SOD水平升高(P<0.05),细胞抑制率、凋亡率、Caspase-3,Bax,G0/G1期细胞数目、LDH,MDA水平下降(P<0.05); 与药物组、药物+Control siRNA组比较,细胞贴壁功能受损,miR-129,Bcl-2蛋白水平、S期及G2/M期细胞数目、T-SOD水平降低(P<0.05),细胞抑制率、凋亡率、Caspase-3,Bax,G0/G1期细胞数目、LDH,MDA水平升高(P<0.05)。结论 当归含药血清对于阿尔茨海默病细胞模型具有一定的保护作用,其机制可能与上调miR-129表达有一定关系。     

Knockdown of miR-372 Inhibits Nerve Cell Apoptosis Induced by Spinal Cord Ischemia/Reperfusion Injury via Enhancing Autophagy by Up-regulating Beclin-1

To investigate the role of miR-372/Beclin-1 on nerve cell apoptosis induced by spinal cord ischemia/reperfusion injury (SCII). We established in vivo and in vitro SCII model. MiR-372 and Beclin-1 expressions in spinal cord tissues of SCII rats and SCII nerve cells were measured. The cell apoptosis was detected by flow cytometry. MiR-372 inhibitor was used to reduce miR-372 expression. Dual luciferase reporter assay was used to confirm the interaction between miR-372 and Beclin-1. MiR-372 expression in spinal cord tissues of SCII rats and SCII nerve cells was increased, while Beclin-1 expression was decreased. Knockdown of miR-372 could inhibit SCII nerve cell apoptosis. In addition, MiR-372 could negatively regulate Beclin-1 expression. Autophagy inhibitor could inhibit autophagy to promote the apoptosis of SCII nerve cells through decreasing Beclin-1, while interference of miR-372 changed the effect of autophagy inhibitor. Interference of miR-372 could reduce nerve cell apoptosis in SCII via increasing autophagy by up-regulating Beclin-1.     

敲低miR-103b对氧葡萄糖剥夺/复氧诱导的神经元损伤的保护作用研究

目的神经元损伤是脑梗死(cerebral infarction,CI)疾病发生发展的关键因素.微小RNA(miRNAs)在神经功能恢复中起主要作用.本研究旨在探讨miR-103b对人皮质神经元细胞(human cortical neuron,HCN)细胞增殖和凋亡的调节作用和机制.方法HCN暴露于氧葡萄糖剥夺/复氧(OGD/R)条件,在OGD/R诱导之前,用针对miR-103b mimics或inhibitor,以及E2F3过表达载体(E2F3)或空载体Vector转染HCN.使用CCK-8和流式细胞术分别评估细胞增殖和凋亡,使用Western blot检测Bax/Bcl-2比值,活性caspase3,E2F3,以及c-Myc蛋白的表达变化.结果OGD/R暴露后,miR-103b在HCN中上调(P<0.01).miR-103b敲低减轻了OGD/R诱导的细胞增殖活性降低(P<0.05);通过降低Bax/Bcl-2比值并下调活性caspase3来减轻OGD/R诱导的细胞凋亡(P<0.05).E2F3受miR-103b负调控(P<0.01);更重要的是E2F3被验证是miR-103b的靶基因之一,E2F3过表达同样可以减轻OGD/R诱导的细胞增殖活性降低和细胞凋亡增加(P<0.05).结论miR-103b敲低可能通过调节E2F3信号保护HCN免受OGD/R诱导的伤害.     

Gastrodin Attenuates Neuronal Apoptosis and Neurological Deficits after Experimental Intracerebral Hemorrhage

Objective: Gastrodin, a glucoside of gastrodigenin, inhibits cerebral oxidant stress and apoptosis in multiple central nervous system injury, but its effect in intracerebral hemorrhage (ICH) remains unclear. This study investigated the effect of gastrodin on neuronal apoptosis and neurological deficits in rat ICH model. Methods: In vitro experiments were performed using hematoma lysate-induced cell damage model in primary cortical neurons. Rat ICH model was produced by a caudatum injection of collagenase. Gastrodin was intraperitoneal injected after 2 hours following ICH. Cell viability, brain water content, neurological score, western blot, and immunofluorescence experiments were performed. Results: Gastrodin significantly decreased hematoma lysate-induced reduction of cell viability and cell apoptosis in primary cortical neurons. Gastrodin significantly improved brain edema and neurological deficits post-ICH. Moreover, gastrodin administration significantly reduced levels of ROS, 8-OHDG, 3-Nitrotyrosine and MDA, while increased GSH-Px and SOD activity, and stimulated the upregulation of Keap1, Nrf2, and HO-1 signaling at 72 hours post-ICH. Furthermore, gastrodin significantly increased Bcl-2 expression, while reduced level of Bax, active caspase-3 and active caspase-9, also reduced the number of active caspase-3 or TUNEL positive neurons at 72 hours post-ICH. Conclusion: These results suggest that gastrodin is neuroprotective after ICH and the mechanism may be associated with the inhibition of oxidative stress and neuronal apoptosis.     

脑出血患者血肿周围组织神经元凋亡与Bcl-2、Bax蛋白表达关系的研究

目的探讨脑出血(ICH)患者血肿周围组织神经元凋亡与凋亡相关基因Bcl2、Bax蛋白表达的关系。方法采用缺口末端标记法、免疫组化法分别检测ICH患者血肿周围组织神经元凋亡率和Bcl2、Bax表达水平,分析神经元凋亡率与Bcl2、Bax表达及Bax/Bcl2值的关系;出血量与Bcl2、Bax表达及Bax/Bcl2值的关系,以及神经元凋亡率与出血量、病程、神经功能缺损程度评分(NDS)的关系。结果ICH患者血肿周围组织神经元凋亡率及Bcl2、Bax表达明显高于正常对照组(均P<0.01);血肿周围组织神经元凋亡率与Bcl2表达呈负相关(r=-0.682,P<0.01),与Bax、Bax/Bcl2值表达呈正相关(r=0.592、0.740,均P<0.01)。出血量与血肿周围组织Bcl2表达呈负相关(r=-0.677,P<0.01),与Bax表达及Bax/Bcl2值呈正相关(r=0.654、0.751,均P<0.01)。细胞凋亡率与出血量及NDS呈正相关(r=0.829、0.897,均P<0.01),与病程不相关。结论细胞凋亡机制参与了ICH后继发性神经元损伤;Bcl2、Bax蛋白及Bax/Bcl2值对凋亡具有调控作用。     

脑出血大鼠颅内溶血磷脂酸受体1与血肿周围 水肿区细胞凋亡的相关性研究

目的 研究脑出血大鼠颅内溶血磷脂酸受体1(LPA-1)与血肿周围水肿区细胞凋亡的相关性。方法 选取134例Wistar大鼠,随机分为正常组和脑出血组,正常组60例,脑出血组74例,脑出血组大鼠采用立体定向脑内注入法构建脑出血模型; 采用RT-PCR检测LPA-1、Caspase-3表达水平,采用双盲法测定神经功能评分,采用Western blot检测Bax蛋白、Bcl-x蛋白表达水平,采用流式细胞术检测各种细胞水平及细胞凋亡水平,根据Pearson相关性分析法大鼠颅内溶血磷脂酸受体1(LPA-1)、Bax蛋白、Bcl-x蛋白及细胞凋亡的相关性。结果 脑出血组LPA-1、Caspase-3表达水平均明显高于正常组(P<0.05); 脑出血组神经功能评分明显高于正常组(P<0.05); 脑出血组Bax蛋白表达水平显著高于正常组,脑出血组Bcl-x蛋白表达水平明显低于正常组(P<0.05); 脑出血组LPA-1、Caspase-3、Bax蛋白表达水平及神经功能评分持续升高,Bcl-x蛋白表达持续降低,直到第3 d到达顶峰后缓慢恢复,到第7 d恢复到正常评分的80%左右。脑出血组中性粒细胞、淋巴细胞、巨噬细胞、小胶质细胞、细胞凋亡率均明显高于正常组(P<0.05); 脑出血组性粒细胞、淋巴细胞、巨噬细胞、小胶质细胞、细胞凋亡率持续升高,直到第3 d到达顶峰后缓慢降低,到第7 d降低更加显著。LPA-1与Bax蛋白的表达水平呈正相关(r=0.33,P<0.05); LPA-1与Bcl-x蛋白的表达水平呈负相关(r=0.25,P<0.05); LPA-1表达水平与细胞凋亡率呈正相关(r=0.81,P<0.05); Bax蛋白与Bcl-x蛋白的表达水平呈负相关(r=-0.22,P<0.05); Bax蛋白表达水平与细胞凋亡率呈正相关(r=0.71,P<0.05); Bcl-x蛋白表达水平与细胞凋亡率呈负相关(r=0.74,P<0.05)。结论 LPA-1与Caspase-3在大鼠脑出血中高表达,神经功能评分在大鼠脑出血中评分过高,Bax蛋白在大鼠脑出血中高表达,Bcl-x蛋白在大鼠脑出血中低表达,脑出血大鼠细胞凋亡率过高,LPA-1、Bax蛋白、Bcl-x蛋白及细胞凋亡在大鼠脑出血中关系密切,可能具有相关性。     

Dickkopf-1在脑出血大鼠神经元凋亡中的作用及机制研究

目的探讨Dickkopf-1(DKK-1)在脑出血大鼠神经元凋亡中的作用及机制。方法采用随机数字法将40只成年雄性SD大鼠分成对照组(n=13)、假手术组(n=13)及脑出血组(n=14)。通过颅内注射自体外周血制作脑出血模型。采用平衡木行走实验和肌力测验进行脑出血模型评估,并利用Real-time PCR和Western blot检测大鼠脑组织中Bcl-2、Bax、p-Akt、Akt及DKK-1蛋白和mRNA表达水平。分离培养原代大鼠皮质神经元,分为对照组、空载体组、DKK-1过表达组、BTBD10(Akt磷酸化激活剂)过表达组,检测细胞中DKK-1表达水平和Akt磷酸化水平,利用流式细胞术检测各组细胞凋亡。结果脑出血组大鼠平衡木行走得分高于对照组和假手术组(P0.05),而肌力测验评分低于对照组和假手术组(P0.05)。与对照组和假手术组比较,大鼠脑出血部位脑组织Bcl-2表达降低(P0.05),而Bax表达则升高(P0.05),p-Akt表达水平下降(P0.05),DKK-1表达水平上升(P0.05)。DKK-1过表达组神经元凋亡率及p-Akt表达水平均高于空载体组和对照组(均P0.05)。Akt磷酸化激活剂BTBD10过表达组p-Akt水平、Bcl-2蛋白表达高于对照组和空载体组,而Bax蛋白表达则低于对照组和空载体组。BTBD10过表达组神经元存活率高于对照组和空载体组(均P0.05),且BTBD10和DKK-1共转染组大鼠神经元存活率高于DKK-1转染组(P0.05)。结论 DKK-1可能通过抑制Akt的磷酸化促进出血性脑卒中大鼠神经元的凋亡。     

肉桂醛对神经胶质瘤U251细胞生物学行为的影响

目的 探讨肉桂醛对胶质瘤细胞生物学行为的影响及其分子机制。方法 体外培养胶质瘤细胞系U251细胞,分为对照组、低剂量肉桂醛组（40 μmol/L）和高剂量肉桂醛组（80 μmol/L）。采用平板克隆和CCK-8试验检测细胞增殖水平;流式细胞术分析细胞凋亡率;Transwell小室实验和细胞划痕试验评估细胞迁移和侵袭水平;免疫印迹法分析凋亡相关蛋白、PI3K/Akt和Wnt/β-catenin通路相关蛋白表达。结果 肉桂醛明显抑制胶质瘤U251细胞增殖、侵袭、迁移能力（P<0.05）,促进细胞凋亡（P<0.05）;抑制Bcl-2、p-PI3K、p-Akt、 cycling D、C-Myc、β-catenin表达（P<0.05）,促进Cleaved-Caspase-3、Bax表达（P<0.05）;而且,随剂量增大,肉桂醛的作用明显增强（P<0.05）。结论 肉桂醛抑制胶质瘤细胞增殖、侵袭、迁移,促进细胞凋亡,其机制可能与下调PI3K/Akt和Wnt/β-catenin信号通路有关。     

Rosmarinic acid elicits neuroprotection in ischemic stroke via Nrf2 and heme oxygenase 1 signaling

Rosmarinic acid(RA) can elicit a neuroprotective effect against ischemic stroke, but the precise molecular mechanism remains poorly understood. In this study, an experimental ischemic stroke model was established in CD-1 mice(Beijing Vital River Laboratory Animal Technology, Beijing, China) by occluding the right middle cerebral artery for 1 hour and allowing reperfusion for 24 hours. After intraperitoneally injecting model mice with 10, 20, or 40 mg/kg RA, functional neurological deficits were evaluated using modified Longa scores. Subsequently, cerebral infarct volume was measured using TTC staining and ischemic brain tissue was examined for cell apoptosis with TUNEL staining. Superoxide dismutase activity and malondialdehyde levels were measured by spectrophometry. Expression of heme oxygenase-1(HO-1), nuclear factor erythroid 2-related factor 2(Nrf2), Bcl-2, Bax, Akt, and phospho-Ser473 Akt proteins in ischemic brain tissue was detected by western blot, while mRNA levels of Nrf2, HO-1, Bcl-2, and Bax were analyzed using real time quantitative PCR. In addition, HO-1 enzyme activity was measured spectrophotometrically. RA(20 and 40 mg/kg) greatly improved neurological function, reduced infarct volume, decreased cell apoptosis, upregulated Bcl-2 protein and mRNA expression, downregulated Bax protein and mRNA expression, increased HO-1 and Nrf2 protein and mRNA expression, increased superoxide dismutase activity, and decreased malondialdehyde levels in ischemic brain tissue of model mice. However, intraperitoneal injection of a HO-1 inhibitor(10 mg/kg zinc protoporphyrin IX) reversed the neuroprotective effects of RA on HO-1 enzyme activity and Bcl-2 and Bax protein expression. The PI3 K/Akt signaling pathway inhibitor LY294002(10 mM) inhibited Akt phosphorylation, as well as Nrf2 and HO-1 expression. Our findings suggest that RA has anti-oxidative and anti-apoptotic properties that protect against ischemic stroke by a mechanism involving upregulation of Nrf2 and HO-1 expression via the PI3 K/Akt signaling pathway.     

H2S对急性脑梗死大鼠神经功能的保护作用及机制

目的 探讨H2S对急性脑梗死大鼠神经功能的保护作用以及相关机制.方法 将48只健康雄性SD大鼠随机分为假手术组、模型组、生理盐水组和H2S干预组.采用改良Longa法制备大鼠急性脑梗死模型,建模前25min,H2S干预组给予腹腔注射NaHS 28μmol/kg,生理盐水组给予等量生理盐水,分别于苏醒后和术后72h,评估各组大鼠的神经功能缺损.采用TTC染色法检测各组大鼠脑梗死面积,TUNEL法检测各组大鼠脑组织中细胞凋亡情况,Western blot法检测各组大鼠脑组织中PI3K、p-PI3K、Akt、p-Akt、Bcl-2、Bax蛋白的表达.结果 与模型组和生理盐水组相比,H2S干预组大鼠神经功能缺损程度评分、脑梗死面积和细胞凋亡指数均降低,差异均有统计学意义(P<0.05).与模型组和生理盐水组相比,H2S干预组大鼠脑组织中PI3K、Akt、Bcl-2蛋白相对表达量均升高,而p-PI3K、p-Akt、Bax蛋白相对表达量均降低,差异均有统计学意义(P<0.05).结论 H2S可能通过抑制PI3K/Akt信号通路而改变Bcl-2/Bax比例,减小急性脑梗死大鼠脑梗死面积及细胞凋亡指数,保护神经功能.     

神经生长因子对氧合血红蛋白诱导鼠神经细胞凋亡的作用研究

目的 研究神经生长因子(NGF)对氧合血红蛋白(OxyHb)诱导的小鼠神经细胞凋亡的作用,进一步探讨OxyHb诱导细胞凋亡及NGF对神经元保护作用的可能机制.方法 蛛网膜下腔注射OxyHb建立蛛网膜下腔出血的动物模型,尾静脉注射NGF,TUNEL法检测神经细胞凋亡,免疫组织化学法检测Bcl-2、Bax、P75NTR和TrkA表达的情况.结果 注射OxyHb后出现神经细胞凋亡,Bcl-2表达降低,Bax和P75NTR表达增加,在NGF给药组,神经细胞凋亡数明显减少,Bcl-2表达增加.而Bax和P75NTR表达则明显降低.结论 小鼠局部脑组织蛛网膜下腔注射OxyHb可引起小鼠神经细胞发生凋亡,Bax和P75NTR表达增加可能是诱导凋亡的一个主要原因,而静脉注射NGF可以抑制OxyHb诱导的细胞凋亡,其机制可能是通过与受体结合,增加Bel-2蛋白表达,降低Bax和P75NTR表达水平以实现其保护作用.     

Quercetin protects oligodendrocyte precursor cells from oxygen/glucose deprivation injury in vitro via the activation of the PI3K/Akt signaling pathway

The aim of this study was to investigate the protection of quercetin (QUE) on oligodendrocyte precursor cells (OPCs) from oxygen/glucose deprivation (OGD)-induced injury in vitro and explore whether the PI3K/Akt signaling pathway contributed to the protection provided by quercetin. The OGD condition was induced by including 2mM sodium dithionite (Na(2)S(2)O(4)) in glucose-free DMEM medium. The concentration of QUE in this study ranged from 3μM to 81μM. OPCs were identified by immunocytochemical staining. Cell viability was analyzed using the water soluble tetrazolium salt-8 (WST-8) and lactate dehydrogenase assay (LDH). The morphological changes of the nucleus were measured using Hoechst 33258 nuclear staining, and the ratio of apoptotic cells was determined by FITC annexin V- and propidium iodide (PI) flow cytometry assay kit. In addition, the levels of pro-apoptotic proteins such as cleaved-caspase-3 and Bax and the anti-apoptotic proteins p-Akt and Bcl-2 were quantified using western blotting. The results showed that the OPC cell survival rate was significantly increased by incubation in conditioned medium supplemented with QUE as measured by the WST-8 assay, while the LDH release rate was significantly decreased as analyzed by the LDH assay. Furthermore, apoptosis assay showed that the apoptosis ratio of OPCs was also dramatically reduced by QUE. Western blotting showed that the expression levels of Bax and cleaved-caspase-3 proteins were down-regulated, while Bcl-2 and p-Akt were up-regulated. Further study showed that the increase in p-Akt by QUE was reduced by the PI3K inhibitor LY294002. These results indicated that QUE effectively protected OPCs from OGD-induced injury and that the mechanism might be related to the activation of the PI3K/Akt signaling pathway.     

反义miR-21通过调控hTERT表达抑制胶质瘤细胞生长

目的探讨敲低miR-21表达对人胶质瘤细胞系U87细胞功能的影响以及相关作用机制。方法脂质体介导转染miR-21反义寡聚核苷酸（miR-21 inhibitor）敲低U87细胞miR-21的表达。使用实时荧光定量PCR鉴定转染后U87细胞miR-21表达水平;MTT法检测转染后细胞增殖水平,流式法评价转染后细胞周期分布及凋亡变化,并结合Western印迹及RT-PCR验证在U87细胞中miR-21和hTERT间关系。结果体外转染反义miR-21寡聚核苷酸能明显抑制U87细胞生长,诱导其凋亡,并且能够明显下调hTERT表达。结论反义miR-21可能通过下调hTERT表达抑制胶质细胞生长,miR-21可作为胶质瘤基因治疗的靶点。