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1.
利用AChE和NADPH d酶组织化学染色法研究了脑源性神经营养因子 (brain derivedneurotrophicfac tor ,BDNF)和神经营养因子 3(neurotrophin 3,NT 3)对离体培养的胚胎大鼠脊髓胆碱能神经元和一氧化氮能神经元生长发育的影响。结果显示 :BDNF处理组和NT 3处理组AChE阳性神经元数和NADPH d阳性神经元数均显著高于对照组 (P <0 .0 5 )。BDNF组AChE阳性神经元和NADPH d阳性神经元胞体平均直径、每细胞突起数和最长突起长度均显著高于对照组 (P <0 .0 5 )。NT 3组NADPH d阳性神经元的生长发育与对照组无明显差异 ,仅AChE阳性神经元的每细胞突起数和最长突起长度显著高于对照组 (P <0 .0 5 ) ,对胞体发育无影响。结果提示 :BDNF ,NT 3促进脊髓神经元的存活和生长发育 ,二者的作用具有选择性和特异性。  相似文献   

2.
帕金森病患者大脑黑质区多巴胺神经元的退化最明显。目前所知的用于帕金森病的治疗药物能够改善症状.却不能避免中脑多巴胺神经元的退化或死亡,进而引发相关的运动缺陷。胶质细胞源性神经营养因子(GDNF)是迄今所知的对多巴胺神经元最有效的神经营养因子,能够促进神经元的存活、分化和维持。然而,最近的研究数据显示GDNF的临床效用低且存在严重的安全问题。[第一段]  相似文献   

3.
目的:研究神经营养因子NGF、BDNF对AD模型鼠海马移植后行为和形态学变化。方法:24.只AD模型鼠随机分成4组:单纯胚基底前脑细胞悬液移植组(ST组)、含NGF或BDNF胚基底前脑细胞悬液移植组(NGF组)、(BD-NF组)和模型对照组(M组),移植后3月进行行为测试并比较移植区AchE细胞数和纤维密度,运用方差分析和SNK检验进行组间比较。结果:行为测试移植3组明显优于模型M组,含因子组又较ST组效果好(P<0.01),两因子组间差异无显著性(P>0.05);因子组存活细胞数均高于ST组,NGF组细胞数多于BDNF组(P<0.05),纤维密度两组相似(P>0.05)。结论:海马内存活胆碱能神经元能代偿受损胆碱能神经元的功能,改善动物的学习记忆功能;NGF、BDNF均能促进胆碱能神经元存活,增加AchE细胞数目和突起,但BDNF促进神经元突起延伸作用较好,而NGF则对神经元保护作用较强。  相似文献   

4.
神经营养素(neurotrophic,NT)是一种分泌性的二聚体蛋白家族,可以影响动物神经细胞的存活、发育、形态及功能.在哺乳动物中,已知的NT包括以下4种:神经生长因子(nevre growthfactor,NGF)、脑源性营养因子(brain-derived neurotrophic factor,BDNF)、神经营养因子-3(NT3)和神经营养因子-4/5,6(NT4/5,6).  相似文献   

5.
GDNF治疗帕金森氏病研究进展   总被引:1,自引:0,他引:1  
胶质细胞源性神经营养因子(glial-cell-line-derived neurotrophic factor ,GDNF)是黑质纹状体系统中重要的靶源性神经营养因子,对黑质多巴胺能神经元具有保护和修复作用.帕金森氏病(Parkinson's disease , PD)动物模型和临床试验均提示GDNF对帕金森病具有治疗价值.  相似文献   

6.
神经营养素族的临床研究综述   总被引:3,自引:0,他引:3  
神经营养素家族(neurotrophins,NTs)是神经因子(neurokines)的一种,后者泛指一类能促进神经元生长和存活的物质。一、NTs概述NTs的成员包括神经生长因子(NGF)、脑源性神经营养因子(BDNF)、神经营养素3(NT-3)、NT-4、NT-5、NT-6等,均为碱性蛋白质。其中NGF发现最早,是于1953年Levi-Montalcini Hamburg和Cohen在两个鼠肉瘤中发现,后由Cohen从蛇毒和鼠颌下腺中纯化了NGF,经测定证明是蛋白质。在NGF发  相似文献   

7.
胶质细胞源性神经营养因子(GNDF)是胶质细胞分泌的一种神经营养因子,是胶质细胞对神经元发挥保护作用最主要的途径.GNDF对多巴胺能神经元的保护及促生长作用明显,是神经保护治疗帕金森病(PD)首选神经营养因子.而对GDNF信号转导的机制尚不清楚,因此,我们用蛋白质组学的方法寻找参与GDNF信号转导通路的可能信号分子.  相似文献   

8.
背景:目前尚未见骨髓间充质干细胞对活化的小胶质细胞特异性反应的报道,且有关骨髓间充质干细胞在特定微环境下如何维持多巴胺能神经元的存活也缺乏相应的实验证据。 目的:观察骨髓间充质干细胞在活化的小胶质细胞刺激下保护多巴胺能神经元存活的作用。 方法:取Wistar大鼠,贴壁法分离培养骨髓间充质干细胞,体外培养并活化小胶质细胞,酶消化法培养中脑多巴胺能神经元。实验分为5组:骨髓间充质干细胞组;小胶质细胞组;脂多糖+小胶质细胞组;骨髓间充质干细胞+脂多糖+小胶质细胞组;分别取各实验组的培养上清,对中脑多巴胺神经元进行培养。单纯多巴胺能神经元组采用体积分数为10%胎牛血清+DMEM/F12进行培养。采用免疫荧光技术检测不同微环境对多巴胺能神经元存活的影响及不同微环境对骨髓间充质干细胞释放胶质细胞源性神经营养因子的影响。 结果与结论:含有骨髓间充质干细胞的实验组胶质细胞源性神经营养因子的释放量均较相应的对照组高。酪氨酸羟化酶免疫荧光染色结果发现,单纯多巴胺能神经元组神经元的存活率为15%;小胶质细胞组多巴胺能神经元的存活率为10%;骨髓间充质干细胞组多巴胺能神经元的存活率为35%;脂多糖+小胶质细胞组多巴胺能神经元的存活率为5%;而骨髓间充质干细胞+脂多糖+小胶质细胞组多巴胺能神经元的存活率达到了28%,高于除骨髓间充质干细胞组外的其他各组(P < 0.05)。此外体外培养多巴胺能神经元存活率随培养时间延长下降,但含有骨髓间充质干细胞实验组的多巴胺能神经元存活率明显高于相应对照组。提示小胶质细胞活化刺激骨髓间充质干细胞上调胶质细胞源性神经营养因子表达,使得多巴胺能神经元免受毒素的损害,抑制了多巴胺能神经元的延迟性死亡。  相似文献   

9.
胶质细胞源性神经营养因子(GNDF)是胶质细胞分泌的一种神经营养因子,是胶质细胞对神经元发挥保护作用最主要的途径.GNDF对多巴胺能神经元的保护及促生长作用明显,是神经保护治疗帕金森病(PD)首选神经营养因子.而对GDNF信号转导的机制尚不清楚,因此,我们用蛋白质组学的方法寻找参与GDNF信号转导通路的可能信号分子.  相似文献   

10.
胶质细胞源性神经营养因子(GNDF)是胶质细胞分泌的一种神经营养因子,是胶质细胞对神经元发挥保护作用最主要的途径.GNDF对多巴胺能神经元的保护及促生长作用明显,是神经保护治疗帕金森病(PD)首选神经营养因子.而对GDNF信号转导的机制尚不清楚,因此,我们用蛋白质组学的方法寻找参与GDNF信号转导通路的可能信号分子.  相似文献   

11.
The survival of rat postnatal mesencephalic dopamine (DA) neurons in dissociated cell cultures was studied by examining the combinatorial effects of dibutyryl cyclic adenosine monophosphate (db-cAMP), glial cell line-derived neurotrophic factor (GDNF), and brain-derived neurotrophic factor (BDNF), as well as selective inhibitors of protein kinase A (PKA), and mitogen-activated protein kinase (MAPK). Postnatal DA neurons were maintained for 14 days in vitro, and were identified by immunohistochemistry using tyrosine hydroxylase antibody. The survival and growth of DA neurons was significantly increased by the inclusion of either >100 microM db-cAMP or 10 microM Forskolin plus 100 microM IBMX in the culture medium. Neither 10-50 ng/ml GDNF nor 50 ng/ml BDNF alone significantly increased DA neuron survival in vitro. However, the combined use of GDNF and BDNF did increase DA neuron survival, and the addition of either db-cAMP or IBMX/Forskolin to media containing these neurotrophins markedly increased DA neuron survival and growth. The cAMP inhibitor Rp-cAMP, the cAMP-dependent protein kinase A inhibitor H89, and the MAP kinase (MAPK) pathway inhibitor PD98059 significantly reduced the survival of DA neurons when applied alone in the absence of added growth factors. Application of GDNF plus BDNF, or db-cAMP significantly protected the DA neurons from the deleterious effects on survival of either 20 microM H89 or 20 microM PD 98059. The results suggest that BDNF, GDNF, and cAMP produce convergent signals to activate PKA and MAPK pathways which are involved in the survival of postnatal mesencephalic DA neurons in vitro.  相似文献   

12.
Basal forebrain cholinergic neurons, which degenerate in Alzheimer's disease, respond to multiple trophic factors, including the neurotrophins, nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). This dual responsiveness prompted us to investigate the effects of a synthetic chimaeric molecule, containing the active domains of both NGF and BDNF. The NGF/BDNF chimaeric factor exhibited synergistic actions, and was 100-fold more potent than wild-type BDNF in enhancing survival of cultured dissociated basal forebrain cholinergic neurons. This effect was apparently due to true BDNF/NGF synergy, since addition of the two wild-type trophins simultaneously reproduced the effect of the chimaera. Synergy was selective for neurons which respond to both factors; substantia nigra dopaminergic neurons, which respond to BDNF but not NGF, exhibited no potentiation. The chimaeric factor thus revealed a synergy that may normally occur in the brain, and constitutes a potentially novel therapeutic agent with greater potency than naturally occurring individual trophins.  相似文献   

13.
背景:目前尚未见脂肪间质干细胞体外诱导分化成多巴胺能神经元的报道,且有关脂肪间质干细胞维持多巴胺能神经元存活的机制也缺乏实验证据。 目的:观察腺病毒介导胶质细胞系源性神经营养因子基因修饰的脂肪间质干细胞对共培养条件下多巴胺能神经元存活的影响。 设计、时间及地点:细胞学体外对比观察,于2007-03/12在吉林省耳鼻咽喉研究所和教育部吉林大学人兽共患病重点实验室完成。 材料:3周龄Wistar大鼠、孕14 d Wistar大鼠由吉林大学白求恩医学院实验动物中心提供。 方法:采用pAdTrackCV和pAdEasy-1系统构建重组胶质细胞系源性神经营养因子腺病毒。取孕14 d大鼠,采用酶消化法培养中脑多巴胺能神经元。取Wistar大鼠腹股沟处脂肪,酶消化法分离培养脂肪间质干细胞,体外培养至第3代当细胞生长至60%融合时,以病毒滴度为1×109 vp/mL的胶质细胞系源性神经营养因子重组腺病毒作用细胞1 h后,转移到生长培养基继续培养,通过ELISA法检测培养上清胶质细胞系源性神经营养因子水平。设立3组:Ad-GDNF转染共培养组、Ad-GFP转染共培养组分别在脂肪间质干细胞经相应病毒转染24 h后加入分离的多巴胺能神经元,继续培养7 d;单纯多巴胺能神经元培养组不加入脂肪间质干细胞。 主要观察指标:采用免疫荧光技术检测共培养环境对多巴胺能神经元存活的影响,共培养环境对胶质细胞系源性神经营养因子修饰脂肪间质干细胞分化的影响。 结果:脂肪间质干细胞在pAd-GDNF转染24 h后细胞上清中出现胶质细胞系源性神经营养因子蛋白,72 h达高峰,pAd-GDNF对脂肪间质干细胞的转染效率约为80%。酪氨酸羟化酶免疫荧光染色结果发现,Ad-GDNF转染共培养组多巴胺能神经元存活率明显高于单纯多巴胺能神经元培养组、Ad-GFP转染共培养组(55%,15%,25%,P < 0.01)。对共培养7 d的细胞进行酪氨酸羟化酶免疫荧光染色,分别以波长为488 nm和563 nm进行单通道扫描,未发现同时表达绿色荧光蛋白和酪氨酸羟化酶的细胞,表明此共培养环境可能不具备诱导脂肪间质干细胞分化为多巴胺能神经元的条件。 结论:胶质细胞系源性神经营养因子基因修饰的脂肪间质干细胞与胚胎中脑分离出的多巴胺能神经元共培养,能够维持和促进多巴胺能神经元的存活,但可能不具备诱导脂肪间质干细胞分化为多巴胺能神经元的作用。  相似文献   

14.
Recent studies have demonstrated that nerve growth factor (NGF) induces apoptosis of several cell types in the central nervous system through its low-affinity p75 neurotrophin receptor (p75NTR). To test the effect of NGF on embryonic motoneuron survival, we developed an organotypic culture system which allowed the in vitro development of intact embryonic rat spinal cords. In our system, neural tubes were taken and cultured at E13, just before the onset of physiological motoneuron death. After 2 days in vitro (DIV), motoneurons underwent apoptosis over a time-course similar to that in vivo. In this system, the addition of NGF (200 ng/mL) for 2 days enhanced the number of apoptotic motoneurons by 37%. This pro-apoptotic effect was completely reversed by the blocking anti-p75NTR (REX) antibody which inhibits NGF binding to p75NTR. Other neurotrophins, e.g. brain-derived neurotrophic factor (BDNF), neurotrophin 3 (NT3) and neurotrophin 4/5 (NT4/5) did not have any effect, while glial cell-derived neurotrophic factor (GDNF) promoted motoneuron survival. Anti-BDNF blocking antibodies enhanced motoneuron death indicating that endogenous BDNF promotes motoneuron survival in explants. Our results demonstrate, for the first time, that NGF can induce embryonic motoneuron apoptosis through its receptor p75NTR.  相似文献   

15.
Cultured astrocytes are known to possess a range of neurotrophic activities in culture. In order to examine which factors may be responsible for these activities, we have examined the expression of the genes for four known neurotrophic factors – ciliary neurotrophic factor (CNTF), nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophin 3 (NT3) – in purified astrocyte cultures derived from neonatal rat hippocampus. Hippocampal astrocytes were found to express mRNA for three neurotrophic factors – CNTF, NGF and NT3 – at significantly higher levels than other cultured cell types or cell lines examined. BDNF messenger RNA (mRNA), however, was undetectable in these astrocytes. The levels of CNTF, NGF and NT3 mRNA in astrocytes were largely unaffected by their degree of confluency, while serum removal caused only a transient decrease in mRNA levels, which returned to basal levels within 48 h. Astrocyte-derived CNTF was found to comigrate with recombinant rat CNTF at 23 kD on a Western blot. Immunocytochemical analysis revealed strong CNTF immunoreactivity in the cytoplasm of astrocytes, weak staining in the nucleus, but no CNTF at the cell surface. NGF and NT3 were undetectable immunocytochemically. CNTF-like activity, as assessed by bioassay on ciliary ganglion neurons, was found in the extract of cultured astrocytes but not in conditioned medium, whereas astrocyte-conditioned medium supported survival of dorsal root ganglion neurons but not ciliary or nodose ganglion neurons. This conditioned medium activity was neutralized with antibodies to NGF. Astrocyte extract also supported survival of dorsal root ganglion and nodose ganglion neurons, but these activities were not blocked by anti-NGF. Part, but not all, of the activity in astrocyte extracts which sustained nodose ganglion neurons could be attributed to CNTF.  相似文献   

16.
Neurturin (NRTN), artemin (ARTN), persephin (PSPN) and glial cell line-derived neurotrophic factor (GDNF) form a group of neurotrophic factors, also known as the GDNF family ligands (GFLs). They signal through a receptor complex composed of a high-affinity ligand binding subunit, postulated ligand specific, and a common membrane-bound tyrosine kinase RET. Recently, also NCAM has been identified as an alternative signaling receptor. GFLs have been reported to promote survival of cultured dopaminergic neurons. In addition, GDNF treatments have been shown to increase morphological differentiation of tyrosine hydroxylase immunoreactive (TH-ir) neurons. The present comparative study investigated the dose-dependent effects of GFLs on survival and morphological differentiation of TH-ir neurons in primary cultures of E14 rat ventral mesencephalon. Both NRTN and ARTN chronically administered for 5 days significantly increased survival and morphological differentiation of TH-ir cells at all doses investigated [0.1–100 ng/ml], whereas PSPN was found to be slightly less potent with effects on TH-ir cell numbers and morphology at 1.6–100 ng/ml and 6.3–100 ng/ml, respectively. In conclusion, our findings identify NRTN, ARTN and PSPN as potent neurotrophic factors that may play an important role in the structural development and plasticity of ventral mesencephalic dopaminergic neurons.  相似文献   

17.
Nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT3) promote the function and/or survival of basal forebrain (BF) cholinergic neurons in vivo and in culture. The neurotrophin source is commonly thought to be targets of cholinergic neurons and the possibility that local glial sources support cholinergic neurons has not been well examined. These sources, however, may be critical to BF neurons before or even after they reach their targets. We investigated neurotrophin expression in BF astrocytes and its regulation by neural signals. Solution hybridization and immunocytochemical assays revealed that NGF, BDNF, and NT(3) mRNA and proteins were expressed in cultured BF astrocytes. To investigate roles of neuronal signals in neurotrophin regulation, effects of K(+), glutamate, and the cholinergic agonist carbachol were examined. These stimuli affected neurotrophin expression differentially. KCl increased BDNF mRNA but did not alter NGF or NT(3) mRNA. The effect was blocked by nifedipine, suggesting that it was mediated by L-type voltage-dependent calcium currents. Carbachol also increased BDNF mRNA levels without changing NGF or NT(3). Effects were blocked by the muscarinic antagonist, atropine. In contrast, glutamate increased both NGF and BDNF mRNA. NT(3) mRNA again was unaffected. The metabotropic agonist trans-(1S,3R)-1-amino-1,3-cyclopentanedicarboxylic acid (trans-ACPD) reproduced glutamate effects, whereas kainate or N-methyl-D-aspartate (NMDA) plus glycine did not. Lack of antagonism by ionotropic antagonists and blockade of glutamate effects by metabotropic antagonists confirmed metabotropic mediation. We suggest that BF astrocytes are local sources of neurotrophins for BF cholinergic neurons during development and are regulated differentially by specific neuronal signals. Critical neuronal-glial interactions may underlie basal forebrain function.  相似文献   

18.
Kobayashi M  Matsuoka I 《Neuroreport》2000,11(11):2541-2545
Although roles of neurotrophin-3 (NT3) and glial cell line-derived neurotrophic factor (GDNF) are suggested for sympathetic neuron development, survival activity of either NT3 or GDNF alone on cultured embryonic rat sympathetic neurons is low (10-20%). We demonstrate that a combination of both NT3 and GDNF exerts a remarkable survival activity (85%). NT3 and GDNF did not affect expression levels of their receptors. However, stimulation with both NT3 and GDNF caused tyrosine-phosphorylation of Ret/GDNF-receptor at a level higher than that caused by GDNF alone. Furthermore, stimulation with both GDNF and NT3 induced an enhanced Thr308-phosphorylation of Akt kinase. These results suggest that the actions of NT3 and GDNF converge at the Ret/GDNF-receptor to enhance survival of the developing sympathetic neurons through activation of the phosphatidylinositol (PI) 3-kinase/Akt pathway.  相似文献   

19.
Previously, this laboratory has shown that human foetal progenitor cells derived from ventral mesencephalon (VM) can be developmentally directed towards a dopaminergic lineage. In the present study, the effects are reported of several as yet untested differentiation/survival factors on the controlled conversion of neural progenitor cells to dopaminergic neurons. Positive immunoreactivity to tyrosine hydroxylase (TH) and raised levels of dopamine (DA) and its metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC), secreted into culture medium, were used to indicate the presence of the dopaminergic neuronal phenotype, i.e., active TH. Incubation with retinoic acid (RA) (0.5 microM) lead to an increase in the number of cultured cells showing positive immunoreactivity for the neuronal marker, microtubule-associated protein (MAP)-2ab. A concomitant increase in TH-positive immunoreactivity was also demonstrated. The brain-derived neurotrophic factor (BDNF) (50 ng/ml), glial-derived neurotrophic factor (GDNF) (10 ng/ml) and interleukin-1 beta (IL-1 beta) (10 ng/ml) also had positive effects in promoting neural progenitor cell differentiation towards the dopaminergic phenotype in the presence of dopamine (10 microM) and forskolin (Fsk) (10 microM). There was no synergy in this effect when progenitor cells were incubated with all of these agents simultaneously. The trans-differentiation potential of the progenitor cells to be directed towards other neurotransmitter phenotypic lineages was also investigated. It was found that, with the right cocktails of agents, serotonin (Ser) (75 microM), acidic fibroblast growth factor (aFGF) (10 ng/ml), BDNF (50 ng/ml) and forskolin (10 microM), these same cells could be directed down the serotonergic cell lineage pathway (as judged by the appearance of tryptophan hydroxylase (TPH) positive immunoreactivity, and synthesis of 5-HT and its metabolites, secreted into the culture medium). However, no cocktail containing noradrenaline (10 nM-500 microM), BDNF (50 ng/ml) and forskolin (10 microM) was found which promoted differentiation towards the noradrenergic cell phenotype as judged by the absence of any TH or D beta H positive immunoreactivity, and no formation of 3,4-dihydroxyphenylethyleneglycol (DOPEG), the principal metabolite of noradrenaline. The controlled trans-differentiation potential of these cell could pave the way for development and harvesting of large numbers of neurons of the appropriate neurotransmitter phenotype for future transplantation therapies for the treatment of neurodegenerative diseases such as Parkinson's disease (PD) and Alzheimer's disease.  相似文献   

20.
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