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1.
目的研究人参皂甙(Ginsenosides,GS)的3种单体成分GSRb1、Rb3、Rg1对培养的皮层神经细胞的抗缺血效应及其机制。方法体外培养小鼠胎鼠大脑皮层神经细胞,观察缺血/再灌注对神经细胞的毒性及(GSRb1、Rb3、Rg1的保护作用。结果培养的小鼠胎鼠大脑皮层神经细胞缺血/再灌注损伤后,细胞出现明显损伤性变化.神经细胞活性降低,电镜观察显示神经细胞呈变性至坏死等不同程度的损伤,死亡率明显升高.培养上清液中乳酸脱氢酶(LDH)释放量增加,而细胞匀浆中超氧化物歧化酶(SOD)含量明显减少.丙二醛(MDA)生成显著增多。GSRb1、Rb3、Rg160μmol/L能不同程度地抑制缺血/再灌注引起的损伤性改变,培养上清液中LDH释放减少,而细胞匀浆中SOD含量明显增加.MDA生成显著降低。结论(1)GSRb1、Rb3、Rg1对神经细胞有明显的抗缺血效应;(2)GSRb1、Rb3、Rg1抗缺血的作用机制可能与其提高神经细胞抗氧化能力、减少自由基的生成,保护细胞的结构与功能有关。  相似文献   

2.
目的探讨利培酮对N-甲基-D-门冬氨酸(NMDA)诱导的大鼠皮层神经细胞损伤的作用。方法清洁级Sperague-Dawley妊娠大鼠3只,孕期17~19 d。用50 μmol/L NMDA处理原代培养的大鼠皮层神经元15 min,观察不同浓度(0.1 μmol/L,1 μmol/IL,10 μmol/L)的利培酮对这种损伤的作用。结果 NMDA(50 μmol/L)处理15 min能显著增加上清液中的乳酸脱氢酶(LDH)活性(P<0.01),明显降低皮层神经细胞甲基噻唑基四唑(MTT)比色后的吸光度(P<0.01)。1μmol/L浓度水平的利培酮能抑制NMDA诱导的大鼠皮层神经元LDH的释放,使MTT比色增强,明显改善损伤后的神经元形态。结论利培酮对NMDA诱导的大鼠皮层神经元的损伤有保护作用。  相似文献   

3.
目的探讨人参皂甙Rb1(GSRb1)对模拟缺血环境中的大鼠神经元胞内游离钙的影响。方法对大鼠胚胎脑海马神经元进行体外培养,将其置于正常细胞外液(正常对照组)、模拟缺血的细胞外液(缺血组)、无钙的模拟缺血液(缺血+无钙组)、以及模拟缺血液+不同浓度的GSRb1溶液[缺血+GSRb1(20、40、60、80μmol/L组)],采用激光共聚焦技术测定各组细胞内钙荧光强度,并计算与正常对照组相比荧光强度变化百分比。结果与正常对照组相比,荧光增强度缺血组为(73.5±10.31)%,缺血+无钙组为(4.5±2.58)%,缺血+不同浓度GSRb1组(20、40、60、80μmol/L组)分别为(20.2±3.41)%、(13.6±2.98)%、(10.5±3.62)%和(12.7±4.51)%;缺血+各浓度GSRb1组的荧光增强度明显小于缺血组(均P<0.01)。结论缺血缺氧时神经细胞内游离钙的上升主要是来自细胞外钙离子内流;GSRb1可通过抑制细胞外钙离子内流,减轻细胞内的钙超载,保护缺血神经元;保护作用呈浓度依赖性,在60μmol/L时达到最大。  相似文献   

4.
刺五加皂甙对神经元谷氨酸毒性损伤的保护作用   总被引:7,自引:0,他引:7  
目的:观察不同谷氨酸浓度和谷氨酸作用不同时间对神经元活性的影响,探讨细胞损伤后刺五加皂甙(ASS)的有效保护浓度。方法:取孕13~15dICR小鼠,无菌条件下对胎鼠大脑皮层神经元进行原代分离培养,建立谷氨酸诱导的皮层神经元损伤模型。用MTT、LDH测定神经元活性,用硝酸还原酶法测定细胞培养上清液中NO的含量,用流式细胞仪检测细胞凋亡率,并在电镜下观察细胞形态学变化。结果:①经谷氨酸处理的神经元,其细胞存活率呈剂量和时间依赖下降、ASS能不同程度提高细胞存活率。②谷氨酸处理组的神经元凋亡率、LDH释放量和NO含量均升高,与正常对照组及ASS组比较有明显差异(P<0.01)。结论:一定浓度的ASS对谷氨酸引起的神经元损伤有保护作用;ASS可能是通过抑制NO的释放和稳定细胞膜,拮抗细胞元损伤。  相似文献   

5.
目的旨在应用不同浓度Aβ_(1-42)诱导新生SD大鼠海马神经元,建立稳定阿尔茨海默病细胞模型。方法分离并培养新生24 h内SD大鼠原代海马神经细胞;分别加入不同浓度Aβ_(1-42)诱导,诱导后采用MTT法观察细胞活力,选取理想Aβ_(1-42)诱导的海马神经细胞作为阿尔茨海默病细胞模型;通过免疫荧光技术(IF)鉴定神经元特异性烯醇化酶(NSE)在海马神经元细胞的表达。结果 Aβ_(1-42)诱导后的海马神经细胞存活率下降,可导致海马神经元细胞胞体变形、收缩和细胞膜完整性破坏,胞间网络结构消失或断裂,细胞外基质乱不清,神经元大量凋亡;Aβ_(1-42)诱导后的海马神经细胞存活率下降与Aβ_(1-42)浓度成线性关系;加入不同浓度Aβ_(1-42)(0μmol/L、10μmol/L、20μmol/L、30μmol/L、40μmol/L和50μmol/L)后实验各组细胞存活率分别为(100.00±0.00)%、(98.55±1.42)%、(90.37±3.25)%,(66.34±2.76)%、(53.23±3.41)%和(41.55±2.37)%,其中20μmol/L组与0μmol/L组相比P<0.05,30μmol/L、40μmol/L和50μmol/L组与对照组相比P<0.01。结论 Aβ_(1-42)可导致海马神经元大量凋亡;Aβ_(1-42)浓度为20μmol/L诱导的SD大鼠海马神经元可作为理想的阿尔茨海默病细胞模型。  相似文献   

6.
9种人参皂甙对培养鼠胚脊髓神经元生长的影响   总被引:9,自引:0,他引:9  
目的:探讨9种主要人参皂甙单体对体外培养鼠胚脊髓运动神经元和脊神经节感觉神经元生长的影响。材料和方法:孕期15d的SD雌鼠,取其胎鼠,消化法混合培养鼠胚脊髓运动神经元和脊神经节感觉神经元;MTT法观察9种人参皂甙单体(Rb1、Rb3、Rd、Re、Rf、Rg1、Rg2、Rh1、Rh2)对脊髓神经元生长的影响。结果:人参皂甙Rg1、Rb1、Re,Rf、Rh1可明显提高体外培养神经元的活力(P<0.01);而Rb3、Rd、Rg2、Rh2对脊髓神经元活力无明显影响(P>0.05)。结论:人参皂甙对周围神经具有保护神经元作用。  相似文献   

7.
目的探讨阿托伐他汀(atorvastatin,Ato)对β淀粉样蛋白(Aβ)诱导的体外培养原代海马神经元损伤保护作用。方法选用出生0~24hSprague-Dawley大鼠乳鼠,解剖显微镜下分离海马,进行海马神经元体外培养,培养10d后用于实验。将培养的海马神经元分为3组:(1)正常对照组:加入含有1%(质量浓度)DMSO培养基;(2)Aβ1-42组:加入1.25μmol/L Aβ;(3)Aβ(1.25μmol/L)+不同浓度阿托伐他汀组(0.1、0.5、1、2.5μmol/L)。应用CellTiter-GloTM荧光细胞活性试剂盒检测培养海马神经元ATP含量,用以反映神经元活力;通过CytoTox-ONETM试剂盒测定培养细胞上清液中乳酸脱氢酶(LDH)含量,用以测定神经元细胞膜的损伤程度;应用免疫荧光染色观察神经元突触素(SYP)、突触后致密蛋白95(PSD-95)、bassoon蛋白表达。Western印迹法半定量检测海马神经元突触蛋白SYP、PSD-95、bassoon的改变。结果与正常对照组比较,培养10d海马神经元经1.25μmol/L Aβ1-42作用48h后,其ATP和LDH水平均明显降低(均P0.01),而0.5、1.0、2.5μmol/L Ato组能够明显抑制Aβ1-42引起的ATP和LDH水平降低(P0.01)。免疫荧光及Western blot结果显示,1.25μmol/L Aβ1-42可使海马神经元SYP、PSD-95、bassoon蛋白表达明显降低,而Ato能够明显抑制Aβ1-42引起的SYP、PSD-95、bassoon蛋白表达降低。结论 Ato对Aβ诱导的体外培养海马神经元毒性有保护作用,这种保护作用可能与Ato对抗Aβ1-42引起的海马神经元SYP、PSD-95、bassoon表达降低有关。  相似文献   

8.
目的研究天麻素对糖氧剥夺(oxygen-glucose deprivation,OGD)大鼠皮层神经元损伤的保护性作用及EphA4表达的影响。方法提取新生大鼠大脑皮层神经元体外培养7 d,对4组神经元分别施以60 min的OGD,换回正常培养液培养30 min后分别及给予含终浓度为50、125、250、500μmol/L天麻素的培养液作为后处理措施,培养4 h后换回正常条件培养24 h;采用倒置相差显微镜观察神经元形态学变化,LDH活性测定检测神经元损伤情况,CY3荧光染色检测EphA4表达变化。结果天麻素后处理能降低糖氧剥夺神经元的损伤,降低EphA4表达。结论天麻素对糖氧剥夺神经元损伤有保护作用,该作用与EphA4表达降低有关。  相似文献   

9.
目的 探讨分子血红蛋白 (MHb)的生物活性 ,为该类血液代用品在脑复苏领域的应用提供理论依据。方法 采用 12~ 15 d胎鼠脊髓神经元进行原代分散培养 ,观察 1、10、5 0μmol/ L不同浓度 MHb对神经元形态和活性的影响。结果 作用 2 4h时各实验组脊髓神经元均观察到毒性反应 ,神经元活性也明显低于空白对照组 (P<0 .0 1)。超氧化物歧化酶 (SOD)和甘露醇能够抑制 MHb的毒性作用。结论 氧自由基介导了 MHb对脊髓神经元的毒性作用 ,提示对 MHb进行修饰来防止自由基生成的必要性。  相似文献   

10.
银杏内酯B抗缺血神经元凋亡的预适应作用   总被引:1,自引:0,他引:1  
目的研究银杏内酯B(Ginkgolide B,GB)对缺血引起的神经元凋亡的影响,并从预适应角度探讨其可能的机制。方法原代培养的小鼠皮层神经元,经过短时缺血预适应(1%O2,无糖DMEM)或GB预处理(120μmol/L,24h)后,再进行严重缺血损伤,通过MTT比色法观察细胞的活性,Hoechst 33342荧光染色检测细胞的凋亡;Western-blot分析磷酸化糖原合成酶激酶-3β(phosphorylated glycogen synthase kinase-3β,p-GSK-3β)和活化的Caspase-3蛋白表达量的变化。结果神经元缺血后活性下降,凋亡比率增高;缺血预适应或银杏内酯B预处理可提高缺血神经元p-GSK-3β的表达,抑制Caspase-3的活化,提高缺血神经元的活性,降低凋亡比率。结论银杏内酯B对缺血诱导的神经元凋亡具有拮抗作用,其作用机制与缺血预适应相似,两者均能提高p-GSK-3β的表达,抑制Caspase-3的活化,银杏内酯B对神经元可发挥药理性预适应作用。  相似文献   

11.
The microglia-mediated inflammatory reaction promotes neuronal damage under cerebral ischemia/hypoxia conditions. We therefore speculated that inhibition of hypoxia-induced microglial activation may alleviate neuronal damage. To test this hypothesis, we co-cultured ginsenoside Rb1, an active component of ginseng, and cortical neurons. Ginsenoside Rb1 protected neuronal morphology and structure in a single hypoxic culture system and in a hypoxic co-culture system with microglia, and reduced neuronal apoptosis and caspase-3 production. The protective effect was observable prior to placing in co-culture. Additionally, ginsenoside Rb1 inhibited levels of tumor necrosis factor-α in a co-culture system containing activated N9 microglial cells. Ginsenoside Rb1 also significantly decreased nitric oxide and superoxide production induced by N9 microglia. Our findings indicate that ginsenoside Rb1 attenuates damage to cerebral cortex neurons by downregulation of nitric oxide, superoxide, and tumor necrosis factor-α expression in hypoxia-activated microglia.  相似文献   

12.
Ginseng, the root of Panax ginseng C.A. Meyer (Araliaceae), is a well known and popular herbal medicine used worldwide. Among more than 30 ginsenosides, the active ingredients of ginseng, ginsenosides Rb1 and Rg1 are regarded as the main compounds responsible for many pharmaceutical actions of ginseng. In our study, primary cultures from embryonic mouse mesencephala were exposed to neurotoxic glutamate concentration and potential protective effects of these two ginsenosides on survival and neuritic growth of dopaminergic cells were tested. Treatment of primary mesencephalic culture with 500 microM glutamate for 15 min on the 10th day in vitro (DIV) increased the release of lactate dehydrogenase (LDH) into the culture medium, the propidium iodide (PI) uptake by cultured cells and the total number of nuclei with condensed and fragmented chromatin (apoptotic features) as evaluated with Hoechst 33342. Moreover, it extensively decreased the number of tyrosine hydroxylase immunopositive (TH+) cells and adversely affected the length and number of their neuronal processes. The toxic effect of glutamate was primarily mediated by over-activation of N-methyl-D-aspartate receptor (NMDA) as treatment of cultured cells with (+)-MK 801, an NMDA receptor antagonist, nearly abolished dopaminergic cells loss and LDH release induced by glutamate. When either ginsenoside was added alone for six consecutive days (at final concentrations 0.1, 1, 10, 20 microM), ginsenoside Rb1 (at 10 microM) significantly enhanced the survival of dopaminergic neurons compared to untreated controls. In these cultures, neurite lengths and numbers were not affected by both ginsenosides. Against glutamate exposure, ginsenosides Rb1 and Rg1 could not prevent cell death. However when pre-treating for 4 days or post-treating for 2 days following glutamate exposure, they significantly increased the numbers and lengths of neurites of surviving dopaminergic cells. Thus our study indicates that ginsenosides Rb1 and Rg1 have a partial neurotrophic and neuroprotective role in dopaminergic cell culture.  相似文献   

13.
Spinal cord injury is a major cause of disability and results in many serious physical, psychological, and social difficulties. Numerous studies have shown that traumatic spinal cord injuries (SCI) lead to neuronal loss and axonal degeneration in and around the injury site that cause partial disability or complete paralysis. An important strategy in the treatment of SCI is to promote neuron survival and axon outgrowth, making possible the recovery of neural connections. Using an in vitro survival assay, we have identified ginsenosides Rb1 and Rg1, extracted from ginseng root (Panax ginseng C. A. Meyer), as efficient neuroprotective agents for spinal cord neurons. These compounds protect spinal neurons from excitotoxicity induced by glutamate and kainic acid, as well as oxidative stress induced by H(2)O(2). The neuroprotective effects are dose-dependent. The optimal doses are 20-40 microM for ginsenosides Rb1 and Rg1. The effects are specific for Rb1 and Rg1, since a third ginsenoside, Re, did not exhibit any activity. Ginseng has been used for thousands of years in the treatment of neurological disorders and other diseases in Asia. Ginsenosides Rb1 and Rg1 represent potentially effective therapeutic agents for spinal cord injuries.  相似文献   

14.
Mitochondrial dysfunction is one of the major pathological changes seen in Alzheimer's disease (AD). Amyloid beta-peptide (Aβ), a neurotoxic peptide, accumulates in the brain of AD subjects and mediates mitochondrial and neuronal stress. Therefore, protecting mitochondrion from Aβ-induced toxicity holds potential benefits for halting and treating and perhaps preventing AD. Here, we report that administration of ginsenoside Rg1, a known neuroprotective drug, to primary cultured cortical neurons, rescues Aβ-mediated mitochondrial dysfunction as shown by increases in mitochondrial membrane potential, ATP levels, activity of cytochrome c oxidase (a key enzyme associated with mitochondrial respiratory function), and decreases in cytochrome c release. The protective effects of Rg1 on mitochondrial dysfunction correlate to neuronal injury in the presence of Aβ. This finding suggests that ginsenoside Rg1 may attenuate Aβ-induced neuronal death through the suppression of intracellular mitochondrial oxidative stress and may rescue neurons in AD.  相似文献   

15.
Summary. Ginsenosides Rb1 and Rg1 are the main active ingredients of Panax ginseng C.A. Meyer (Araliaceae). They appear to exert protection against ischaemia and anoxic damage in animal models, suggesting an antioxidative and cytoprotective role. In our study, primary cultures from embryonic mouse mesencephalon are applied to examine the effects of these two ginsenosides on neuritic growth of dopaminergic cells and their survival affected by 1-methyl-4-phenylpyridinium-iodide (MPP+). Ginsenoside Rb1 (at 10µM) enhanced the survival of dopaminergic neurons by 19% compared to untreated control. MPP+ (at 1µM) significantly reduced the number of dopaminergic neurons and severely affected neuronal processes. Both ginsenosides counteracted these degenerations and significantly protected lengths and numbers of neurites of TH+ cells. Both compounds however could not prevent the cell loss caused by MPP+. Our study thus indicates partial neurotrophic and neuroprotective actions of ginsenosides Rb1 and Rg1 in dopaminergic cell culture.  相似文献   

16.
Ginseng, the root of Panax ginseng C.A. Meyer (Araliaceae), is a widely used herbal medicine. Ginsenosides, the active ingredients of ginseng, are the main components responsible for many beneficial actions of ginseng. In the present study, we tested 10 different ginsenosides in the previously developed in vitro Huntington's disease (HD) assay with primary medium spiny striatal neuronal cultures (MSN) from the YAC128 HD mouse model. We found that nanomolar concentrations of ginsenoside Rb1 and Rc effectively protected YAC128 medium spiny neurons from glutamate‐induced apoptosis and that Rg5 was protective at micromolar concentration. The other seven ginsenosides tested were not effective or exerted toxic effects in MSN cultures. From further experiments, we suggested that neuroprotective effects of ginsenosides Rb1, Rc, and Rg5 could correlate with their ability to inhibit glutamate‐induced Ca2+ responses in cultured MSN. From these results we concluded that ginsenosides Rb1, Rc, and Rg5 offer a potential therapeutic choice for the treatment of HD and possibly other neurodegenerative disorders. © 2009 Wiley‐Liss, Inc.  相似文献   

17.
目的探讨神经生长因子对糖皮质激素诱导的大鼠海马神经元凋亡的保护作用。方法体外分离原代培养18只新生Wister大鼠海马神经元,噻唑蓝法测定地塞米松诱导海马神经元凋亡的最低敏感剂量,观察不同质量浓度神经生长因子对地塞米松(0.10×10~(-6)mol/L)诱导海马神经元凋亡的保护作用。结果与阴性对照组相比,地塞米松Ⅰ组(10×10~(-6)mol/L)、Ⅱ组(1×10~(-6)mol/L)和Ⅲ组(0.10×10~(-6)mol/L)大鼠海马神经元活性均降低(P=0.000,0.000,0.000)。予不同质量浓度神经生长因子后,神经生长因子0.18 ng/ml组大鼠海马神经元活性低于阴性对照组(P=0.000)和阳性对照组(P=0.010),神经生长因子18 ng/ml组大鼠海马神经元活性高于阳性对照组(P=0.000)和神经生长因子0.18 ng/ml组(P=0.000)。结论糖皮质激素可以诱导体外培养的大鼠海马神经元凋亡,地塞米松0.10×10~(-6)mol/L是诱导海马神经元凋亡的最低敏感剂量,神经生长因子可以拮抗地塞米松诱导的大鼠海马神经元凋亡。  相似文献   

18.
We investigated the cognition enhancing effects of ginsenoside Rb1 and Rg1. Mice were trained in a Morris water maze following injection (i.p.) of Rb1 (1 mg/kg) or Rg1 (1 mg/kg) for 4 days. Both Rb1- and Rg1-injected mice showed enhanced spatial learning compared to control animals. The hippocampus, but not the frontal cortex, of treated mice contained higher density of a synaptic marker protein, synaptophysin, compared to control mice. Electrophysiological recordings in hippocampal slices revealed that Rb1 or Rg1 injection did not change the magnitude of paired-pulse facilitation or long-term potentiation. Our results suggest that Rb1 and Rg1 enhance spatial learning ability by increasing hippocampal synaptic density without changing plasticity of individual synapses.  相似文献   

19.
目的研究低分子肝素(low molecular weight heparin,LMWH)对大鼠大脑皮层神经细胞缺血再灌注损伤的保护作用及其可能机制。方法体外培养新生大鼠大脑皮层神经细胞,建立缺血再灌注模型,MTT法检测细胞活力,Annexin V-FITC、PI双染流式测细胞凋亡率,荧光分光光度计法测定细胞内钙离子浓度。结果低分子肝素可提高缺血再灌注损伤的神经细胞活力,降低细胞凋亡率和细胞内钙离子浓度。结论低分子肝素对缺血再灌注损伤的大鼠大脑皮层神经细胞有保护作用,其机制可能与LMWH降低细胞内钙离子浓度有关。  相似文献   

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