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1.
胶质细胞源性神经营养因子与脑缺血   总被引:1,自引:0,他引:1  
胶质细胞源性神经营养因子 (GDNF)是转化生长因子(TGF- β)超家族成员 ,最近已被纯化并克隆 ,是一个最有效的营养因子。对 GDNF的研究始于十年前 ,Schubert等为了研究神经系统中不同细胞系蛋白的表达 ,用两种不同规格的凝胶进行电泳检测 ,比较不同克隆的神经元和胶质细胞系蛋白表达情况 ,结果发现电泳带是完全不同的。当时由于缺乏对较低含量蛋白的分离和鉴别技术而未能进一步研究 [1 ] 。后来发现胶质细胞系 B49、R33和 JSC1具有分泌促进多巴胺脑神经元存活的蛋白质 [2 ] 。 1993年 L in等从 B49神经胶质瘤细胞的条件培养液中纯化…  相似文献   

2.
目的 观察大鼠脑缺血再灌流时胶质源性神经营养因子(GDNF)在脑组织的分布特点,及其在缺血性脑损伤中的作用。方法 阻断大鼠大脑中动脉(MCA)血流2小时,再灌流0.5-48小时制成局灶性脑缺血模型,HE染色评价缺血性脑损伤的组织学特点,免疫组化法观察GDNF在脑组织的分布特点。结果 再灌流0.5小时组有灶性缺血区,24小时组面积最大,包括视前区、纹状体和皮质。再灌注6小时组开始出现神经元不可逆变性,24小时组梗死形成。再灌注0.5小时组,缺血区皮质神经元GDNF弱阳性,缺血周边区中等阳性;再灌流3-48小时组,缺血区神经元GDNF阴性。再灌流48小时组视前区的梗死周边区巨噬细胞GDNF呈强阳性。GDNF阳性细胞计数显示缺血区各实验组与正常组相比均减少(均P<0.01);24小时和48小时组分别与0.5小时组和3小时组相比,GDNF阳性细胞数减少(分别P<0.01)。结论 缺血性脑损伤时,变性死亡的神经元GDNF不表达,存活的神经元和活化的小胶质细胞或巨噬细胞的GDNF表达增加。  相似文献   

3.
脑缺血损伤在世界范围内是人类致死的主要原因之一[1].临床和基础研究均表明,神经营养因子在脑缺血后神经元的损伤和修复过程中具有重要作用.胶质细胞源性神经营养因子(GDNF)是神经营养因子家庭中的一名新成员,在脑缺血损伤中对神经元具有保护作用,目前已经成为神经科学研究领域的一个"热点"[2].本文就GDNF对脑缺血损伤的保护作用有关内容作一综述.  相似文献   

4.
探讨脑缺血再灌流不同时程及不同程度缺血对海马及皮层胶质源性神经营养因子(glialcellline derived neurotrophic factor, GDNF)基因表达的影响,以及N甲基D天冬氨酸(Nm ethylDsapartate, NMDA)受体拮抗剂,钙离子通道阻断剂是否能调节缺血病态下GDNFm RNA的表达。参照Sm ith 等方法建立大鼠前脑缺血再灌流动物模型。用DIGOligonucleotide 3′end labeling Kit,标记51 m er的GDNF寡核苷酸探针在含有海马结构的冰冻组织切片上进行原位杂交检测GDNFm RNA的表达。10 m in 缺血再灌流2 h,齿状回GDNFm RNA表达上调。再灌流6 h,CA1,CA3 和皮层PAR区GDNFm RNA表达亦见增多,24 h 达高峰。Ketam ine 可使GDNF的基因表达在海马结构及皮层PAR区明显低于相应的缺血再灌流组,统计学差异显著(P< 005)。脑缺血再灌流时GDNF基因表达增加,对缺血神经元可能起保护作用。Ketam ine可阻断缺血后GDNFm RNA 的表达增加,提示NMDA谷氨酸受体很可能参与介导了缺  相似文献   

5.
目的 研究胶质细胞源性神经营养因子 (glial cell line-derived neurotrophic factor,GDNF)对脑缺血再灌注损伤保护作用的时间窗及其保护作用机制。方法 应用免疫组织化学方法观察 GDNF对缺血半暗带Caspase-3及 TNFα蛋白表达的影响 ;TTC染色测定梗死灶体积。结果 与对照组比较 (3 2 3 .1± 49.6) ,0 h及 1h给药组梗死灶体积减小 (193 .4± 53 .8,2 41.1± 57.5) ,0 h组 Caspase-3蛋白表达减少 (10 7.2± 9.5及 92 .3± 6.5) ,各组 TNFα蛋白的表达差异均无显著性。结论  GDNF对脑缺血再灌注损伤保护作用的时间窗在 3 h之内 ,其作用机制可能与抑制 Caspase-3介导的细胞凋亡有关  相似文献   

6.
目的 :观察脑缺血再灌注损伤后脑皮层、梗塞区和海马神经元脑源性神经营养因子 (BDNF)水平的变化 ,及与脑病理变化的关联性 ;探讨 BDNF在脑缺血再灌注损伤中的可能作用机理。方法 :线栓法复制大鼠大脑中动脉脑缺血再灌注模型 ,原位核酸分子杂交检测脑不同区域 BDNFm RNA,图象分析间接定量其水平。结果 :1.脑缺血及缺血再灌注均能诱导双侧脑皮层、海马和梗塞区及其对侧相应区神经元 BDNFm RNA水平增高。2 .梗塞区因缺血损伤过重 ,神经元 BDNFm RNA水平增高的幅度小。 3.再灌注后神经元 BDNFm RNA的水平继续升高 ;其变化规律在不同脑区大致相似。 4.神经元 BDNFm RNA基础水平与神经元抗损伤力呈正相关。结论 :脑缺血及缺血再灌注损伤均导致双侧大脑 BD-NFm RNA表达的变化 ,BDNFm RNA水平的提高能增强神经元的抗损伤能力。  相似文献   

7.
目的 从胶质细胞源性神经营养因子(GDNF)对大鼠局灶脑缺血梗死灶、半胱氨酸蛋白酶(Caspase-3)表达、细胞凋亡等方面的影响,研究其对大鼠局灶脑缺血的作用及其机制。方法 健康雄性Wistar大鼠120只,随机分为GDNF组和生理盐水组,每组又分为假手术组、缺血oh、3h、6h、24h组,采用大脑中动脉线栓模型,于栓塞同时大鼠脑室内分别给予GDNF和生理盐水5μL。检测脑梗死体积百分比、Caspase-3的表达、细胞凋亡等改变。结果 GDNF组脑梗死体积比明显小于生理盐水组;神经元损伤明显轻于生理盐水组,特别是海马区神经元在GDNF组无明显损伤;GDNF组(Caspase-3表达和TUNEL染色阳性细胞数明显少于生理盐水组。结论 GDNF对大鼠局灶脑缺血有保护作用,抑制Caspase-3的表达和细胞凋亡是其保护机制之一。  相似文献   

8.
背景:研究显示,细胞移植对脑出血脑损伤有保护作用,有学者在脑梗死后移植骨髓基质干细胞能促进大鼠神经功能恢复。 目的:观察移植胶质细胞源性神经营养因子基因修饰的骨髓基质干细胞是否比单纯骨髓基质干细胞移植对脑出血有更好的保护作用。 方法:采用自体血制作大鼠脑出血模型,36只SD成年大鼠随机抽签法分为3组,每组按不同时间点分为2个亚组,每个时间点6只。胶质细胞源性神经营养因子/骨髓基质干细胞组、骨髓基质干细胞组分别在脑出血壳核注射胶质细胞源性神经营养因子基因修饰的骨髓基质干细胞、骨髓基质干细胞20 μL/只;对照组注射生理盐水20 μL。分别在1,2周处死大鼠,免疫组织化学染色观察突触素和神经生长相关蛋白在脑出血周边区的表达。 结果与结论:各时间点胶质细胞源性神经营养因子/骨髓基质干细胞组的突触素和神经生长相关蛋白43免疫阳性产物比骨髓基质干细胞组和对照组显著增加(P < 0.05)。提示胶质细胞源性神经营养因子基因修饰的骨髓基质干细胞比单一骨髓基质干细胞对大鼠脑出血有更好的保护作用。  相似文献   

9.
目的 将脑源性神经营养因子(BDNF)基因转入大鼠海马原代培养的神经干细胞(NSCs)中,获得NSCs-BDNF基因工程干细胞并移植治疗大鼠缺血性脑损伤.方法 分离培养新生大鼠海马区NSCs,检测其增殖、分化等特性;构建逆转录病毒载体pLXSN-BDNF,转染NSCs,获得NSCs-BDNF基因工程干细胞,检测其BDNF的表达和活性;建立大鼠大脑中动脉局灶性脑缺血模型,通过立体定向技术将NSCs-BDNF移植入模型缺血侧海马,进行组织学和行为学检测.结果 NSCs-BDNF移植后可以观察到动物行为学的改善,术后4周Longa评分1.343±0.293,脑切片可以观察到海马齿状回神经元数目的增加,术后4周存活率87.5%±6.6%,较对照有统计学意义(P<0.05).结论 NSCs-BDNF移植对实验性大鼠缺血性脑损伤有修复作用.  相似文献   

10.
背景:近年来,已有实验证实经颅直接给予胶质细胞源性神经营养因子(glial cell-derived neurotrophic factor,GDNF)或携带GDNF基因病毒载体有显著减少脑梗死体积、促进神经功能恢复的疗效,但其治疗方法有创,临床应用有限。 目的:观察GDNF基因转染的人脐血CD34+细胞经静脉移植对自发性高血压大鼠脑梗死的疗效,并探讨其机制。 方法:分离人脐血CD34+细胞,脂质体方法转染pEGFP-GDNF质粒和pEGFP空载体至CD34+细胞制备pEGFP-GDNF-CD34+和pEGFP-CD34+细胞;制备60只雄性自发性高血压大鼠大脑中动脉栓死模型并随机分为3组:pEGFP-GDNF-CD34+细胞移植组(基因细胞组)、pEGFP-CD34+细胞移植组(单纯细胞组)、生理盐水组。改良神经功能损害评分评价神经功能恢复状况;图像分析法观察TTC染色脑梗死体积;酶联免疫法检测细胞培养液与脑组织匀浆GDNF水平,荧光显微镜及免疫组织化学检测绿色荧光蛋白标记CD34+细胞及其人神经胶质纤维酸性蛋白和人神经元核抗原表达。 结果与结论:经静脉移植pEGFP-GDNF-CD34+细胞向自发性高血压大鼠脑缺血区域迁移、存活、并向神经细胞定向分化,促进神经功能恢复。GDNF基因转染CD34+细胞在脑组织存活、向神经细胞分化及对大脑神经功能保护作用优于CD34+细胞。脑组织GDNF水平可能是GDNF基因转染CD34+细胞和单纯CD34+细胞移植治疗自发性高血压大鼠局灶性脑缺血疗效差异机制之一。  相似文献   

11.
Wei G  Wu G  Cao X 《Neuroreport》2000,11(6):1177-1183
The aim of this study was to understand the possible involvement of glial cell line-derived neurotrophic factor (GDNF) in rat brain ischemic injury by examining the expression and the cellular location of GDNF with molecular biological and morphological techniques. Expression of GDNF mRNA and protein was first increased as early as 2h after ischemia-reperfusion in peri-infarct cerebral cortex and striatum; it then declined, and showed a second increase at 72 h. Double staining confirmed that the earlier peak of GDNF expression was of neuronal origin and the later peak of glial origin. Considering the neurotrophic characteristics of GDNF, our findings suggest that elevated endogenous GDNF expression may have important roles in protection of ischemic injured neuronal cells.  相似文献   

12.
This study examined the expression of glial cell line-derived neurotrophic factor (GDNF) mRNA and the cellular localization of GDNF production in rats subjected to transient forebrain ischemia induced by four-vessel occlusion. Transient forebrain ischemia induced GDNF mRNA expression in the hippocampus from 3 h to 3 days after the ischemic episode, with peak expression at 6 h. The GDNF mRNA increase in the cerebral cortex was similar to that in the hippocampus, whereas no increase in GDNF mRNA was observed in the striatum and brainstem. Western blot analysis showed that GDNF in the hippocampal CA1 region was increased slightly from 3 to 24 h after the ischemia, and then subsequently declined to below the baseline level. In the hippocampus, GDNF was evenly produced in pyramidal neurons of both sham-operated rats and normal rats, as determined by immunohistochemistry. Interestingly, we found that ischemia-induced reactive astrocytes, as well as surviving neurons, produced GDNF in 3-7 days after the ischemia. On the other hand, in other regions, such as the cerebral cortex, striatum, and brainstem, there was no change in GDNF-positive cells secondary to ischemia. These findings suggest that expression of GDNF mRNA is regulated in part via ischemia-induced neuronal degeneration. They also suggest that ischemia-induced reactive astrocytes may produce GDNF to protect against neuronal death. Therefore, GDNF may play an important role in ischemia-induced neuronal death in the brain.  相似文献   

13.
To examine a possible protective effect of exogenous glial cell line-derived neurotrophic factor (GDNF) gene expression against ischemic brain injury, a replication-defective adenoviral vector containing GDNF gene (Ad-GDNF) was directly injected into the cerebral cortex at 1 day before 90 minutes of transient middle cerebral artery occlusion (MCAO) in rats. 2,3,5-Triphenyltetrazolium chloride staining showed that infarct volume of the Ad-GDNF-injected group at 24 hours after the transient MCAO was significantly smaller than that of vehicle- or Ad-LacZ-treated group. Enzyme-linked immunosorbent assay (ELISA) for immunoreactive GDNF demonstrated that GDNF gene products in the Ad-GDNF-injected group were higher than those of vehicle-treated group at 24 hours after transient MCAO. Immunoreactive GDNF staining was obviously detected in the cortex around the needle track just before or 24 hours after MCAO in the Ad-GDNF group, whereas no or slight GDNF staining was detected in the vehicle group. The numbers of TUNEL, immunoreactive caspase-3, and cytochrome c-positive neurons induced in the ipsilateral cerebral cortex at 24 hours after transient MCAO were markedly reduced by the Ad-GDNF group. These results suggest that the successful exogenous GDNF gene transfer ameliorates ischemic brain injury after transient MCAO in association with the reduction of apoptotic signals.  相似文献   

14.
Paraplegia is a catastrophic complication of thoracic aortic surgery. At present, there is no effective mean to prevent the ischemia-induced spinal cord trauma. Gene delivery of neurotrophic factors may hold promises for prevention of spinal injury. In the present study, we evaluated the effect of glial cell line-derived neurotrophic factor (GDNF) gene delivery on prevention of the pathological changes due to spinal ischemia. Recombinant adenovirus vectors encoding GDNF (Ad-GDNF) and green fluorescent protein (Ad-GFP) were used for gene transfer studies. Treatment with cobalt chloride induced dose-dependent bcl-2 and synaptophysin downregulation in spinal neuronal cells, which could be effectively reversed by GDNF gene transfer. Intrathecal injection of Ad-GDNF led to maximal GDNF expression in spinal cord within 2-7 days. Thus, after intrathecal administration of adenovirus vectors for 3 days, Sprague-Dawley rats received transient aortic occlusion to induce spinal ischemia and were monitored for behavior deficits. The Ad-GDNF-treated rats showed significantly lower paraplegia rate (40%) than that of Ad-GFP- or saline-treated groups (75-85%; P<0.01). In addition, the Ad-GDNF-treated rats exhibited significantly improved locomotor function comparing with rats of control groups (P<0.001). Histological analysis revealed that GDNF gene delivery profoundly attenuated the infiltration of leukocytes in spinal cord after ischemic insults. Furthermore, GDNF gene delivery prominently attenuated the ischemia-induced neuronal loss in dorsal horn lamina VI-VIII and reduction in synaptophysin expression in spinal cords. In conclusion, GDNF gene transfer confers protection to the neuronal cells and synapses networks, thereby alleviated the paraplegia due to spinal ischemia.  相似文献   

15.
Glial cell line-derived neurotrophic factor (GDNF), a member of the transforming growth factor (TGF)-beta superfamily, is one of the most potent neurotrophic factors and promotes survival of many populations of cells. We examined neuroprotective effect of an adenoviral vector encoding glial cell line-derived neurotrophic factor (AxCAhGDNF) on the transient global ischemia. Gerbils received administration of AxCAhGDNF or an adenoviral vector encoding bacterial beta-galactosidase gene (AxCALacZ) through the lateral ventricle. Two days later, occluding bilateral common carotid arteries for 5 min using aneurysm clips produced the transient global forebrain ischemia. Animals showed intense immunolabeling for GDNF in ependymal cells on 2, 4 and 7 days after the operation. The exogenous gene transducted by adenovirus in the same cells was detected by in situ hybridization. The treatment with AxCAhGDNF significantly prevented the loss of hippocampal CA1 pyramidal neurons 2 to 7 days after the operation, as compared to AxCALacZ treatment. Also terminal deoxynucleotidyl transferase-mediated dUTP-biotin in situ nick end labeling (TUNEL) staining was markedly reduced in the case with AxCAhGDNF treatment at 7 days after the operation. These results indicated that the adenovirus-mediated gene transfer of GDNF might prevent the delayed neuronal death of stroke and other disorders of the cerebral vasculature.  相似文献   

16.
背景:PI3K/Akt通路和BDNF在脑缺血动物模型和患者中表达异常,也成为的脑缺血的治疗靶点。神经干细胞在修复的潜在用途包括移植修复丢失的细胞和激活内源性细胞提供“自我修复。” 目的:观察神经干细胞植入对PI3K/Akt和BDNF在海马表达的影响,阐明神经干细胞植入对脑缺血的神经保护机制。 设计:完全随机分组,对照动物实验。 时间及地点:实验于2007-03-2008.09在南方医科大学基因工程研究所完成。 材料:E17的怀孕大鼠和雌性大鼠购自南方医科大学实验动物中心,兔抗PI3K的试剂盒购自北京博奥森生物科技公司,磷酸化Akt(Ser473)由美国Cell Signaling Technology提供,其他试剂由美国sigma和Santa Cruz公司提供。 方法:体外分离、培养大鼠NSCs,进行WTS-8、 BrdU检测。局灶性脑缺血模型,大脑中动脉线栓方法制作大鼠脑缺血再灌注模型。参照Longa氏5分评分方法,得分超过2分大鼠入选实验。2,3,5,氯化三苯基四唑(TTC)染色检测梗死体积。两天后大脑中动脉阻塞大鼠给与50000 E17的立体定向神经干细胞移植或5μgWortmannin至缺血海马旁。使用免疫印迹分析Akt(Ser473),PI3K和BNDF的表达。 主要观察指标:脑组织神经干细胞移植激活PI3K/Akt通路参与促进神经组织的结构和功能恢复且上调脑源性神经营养因子的功能。 结果:神经干细胞治疗组脑梗死体积显着低于缺血模型组(P<0.01)、Wortmannin干预组(P<0.01)和神经干细胞+Wortmannin干预组(P<0.05)。在神经干细胞治疗组PI3K蛋白的水平比较显着高于脑缺血模型性(P<0.01)。在Akt的蛋白质水平(Ser473)和神经干细胞治疗组BNDF更为显著高于脑缺血模型性(P<0.01)。在治疗组的BNDF蛋白水平比较显着高于Wortmannin干预(P<0.01)神经干细胞+Wortmannin干预组(P<0.05)。 结论:在脑缺血过程中神经干细胞移植激活PI3K/Akt通路参与脑源性神经营养因子的基因表达。  相似文献   

17.
Intravenous administration of human mesenchymal stem cells (hMSCs) prepared from adult bone marrow has been reported to ameliorate functional deficits after cerebral artery occlusion in rats. Several hypotheses to account for these therapeutic effects have been suggested, and current thinking is that neuroprotection rather than neurogenesis is responsible. To enhance the therapeutic benefits of hMSCs potentially, we transfected hMSCs with the glial cell line-derived neurotrophic factor (GDNF) gene using a fiber-mutant F/RGD adenovirus vector and investigated whether GDNF gene-modified hMSCs (GDNF-hMSCs) could contribute to functional recovery in a rat permanent middle cerebral artery occlusion (MCAO) model. We induced MCAO by using intraluminal vascular occlusion, and GDNF-hMSCs were intravenously infused into the rats 3 hr later. MRI and behavioral analyses revealed that rats receiving GDNF-hMSCs or hMSCs exhibited increased recovery from ischemia compared with the control group, but the effect was greater in the GDNF-hMSC group. Thus, these results suggest that intravenous administration of hMSCs transfected with the GDNF gene using a fiber-mutant adenovirus vector may be useful in the cerebral ischemia and may represent a new strategy for the treatment of stroke.  相似文献   

18.
背景:将转染Xbp-1基因的神经干细胞移植至脑损伤病变部位,不但确保了Xbp-1基因的稳定及持续表达发挥抗凋亡的作用,也可促进移植后神经干细胞的存活与分化能力。 目的:验证Xbp-1基因对移植大鼠脑缺血损伤处神经干细胞的分布、分化、抗凋亡作用及神经功能恢复的影响。 方法:选取成年SD大鼠采用线栓法建立大脑中动脉阻塞模型,并随机分成4组干预:对照组(不作处理)、PBS移植组、神经干细胞移植组、Xbp-1-神经干细胞移植组。于干预后7,14,28 d进行NSS评分,并取脑制备组织切片,免疫荧光染色观察神经干细胞在脑内的存活与分布情况。移植后第28天使用TUNEL染色检测缺血区域神经细胞凋亡情况,Western blot检测Bcl-2表达水平。 结果与结论:移植后7,14,28d Xbp-1-神经干细胞移植组NSS评分显著低于其他3组(P < 0.05);神经干细胞可以成功迁徙到脑缺血区域并成活、分化为成熟神经细胞,Xbp-1基因修饰后的神经干细胞成活、增殖以及分化能力均强于普通神经干细胞(P < 0.05);与其他3组比较,Xbp-1-神经干细胞移植组脑缺血区域神经细胞凋亡数量明显减少,Bcl-2水平升高 (P < 0.05)。证实了Xbp-1基因修饰可以增加神经干细胞存活、迁徙能力,并通过抗内质网应激显著降低移植后大鼠缺血模型的NSS评分,促进其神经功能恢复。  相似文献   

19.
背景:在神经干细胞移植治疗帕金森病中,移植细胞的数量及多巴胺能神经元的分化比率是必须解决的问题,而有效的神经干细胞体外增殖与多巴胺能神经元的大量定向诱导分化是解决问题的关键所在。 目的: 探讨胶质源性神经营养因子与白细胞介素1β体外诱导中脑神经干细胞向多巴胺能神经元的分化。 方法:分离妊娠12 d小鼠胚胎腹侧中脑,经胰酶消化和机械吹打制成单细胞悬液,离心过滤后机械方法传代培养5~7 d的神经球,分组进行诱导分化10~12 d,待80%细胞从神经球迁移出来,分化为单细胞时,进行免疫细胞化学鉴定及流式细胞术检测酪氨酸羟化酶阳性细胞率。 结果与结论:神经球细胞表达巢蛋白抗原,能分化为神经元特异性烯醇化酶和胶原纤维酸性蛋白阳性细胞。胶质源性神经营养因子与白细胞介素1β在体外能明显提高中脑神经干细胞分化为酪氨酸羟化酶阳性神经元的比例,胶质源性神经营养因子诱导组、白细胞介素1β诱导组和两者联合应用均较空白对照组比例高,尤其是两者联合应用作用更显著,说明胶质源性神经营养因子、白细胞介素1β可明显促进中脑神经干细胞分化为数量足够、形态及功能成熟的多巴胺能神经元。  相似文献   

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