具有促C17.2神经干细胞增殖作用的多功能咔唑-利凡斯的明二聚体的发现(英文)

目的具有多靶点作用的化合物在治疗神经退行性疾病、心血管疾病、癌症等方面可能比传统"一药一靶"的治疗策略更有效。方法通过结合氨丙基咔唑和氨基甲酸酯两个药效团的方式设计合成了4个具有多功能化合物,并对化合物的促增殖、神经保护、抑制胆碱酯酶的活性进行检测。结果这些化合物可促进C17.2神经干细胞的增殖,对谷氨酸诱导的HT22细胞氧化毒性具有保护作用,具有较好的丁酰胆碱酯酶抑制活性和高血脑屏障透过性。结论这些化合物可能是一种新的多功能药物先导化合物,可以激活或保护内源性神经干细胞,从而重建受损的大脑。     

Optimisation of culture conditions to develop an in vitro pulmonary permeability model.

An in vitro model to study pulmonary translocation was created, using the human cell line Calu-3 and primary rat type II pneumocytes. Cells were seeded on permeable membranes with a 0.4 microm or 3 microm pore size, utilizing different culture conditions such as medium formulation and cell density. The integrity of the cell monolayer was verified by measuring the transepithelial electrical resistance (TEER) and passage of sodium fluorescein. When seeded on inserts with 0.4 microm pore size, the Calu-3 cells and primary rat type II pneumocytes created high TEER values of 949+/-182 Omega cm(2) and 400+/-257 Omega cm(2), respectively. On membranes with 3 microm pores, Calu-3 cells achieved a high TEER value of 500+/-95 Omega cm(2). Our experiments indicate that the culture medium was more critical than the cell density, regarding the influence on TEER values. For both cell types a reduction of serum in the medium resulted in a decrease in TEER value. We established a good ('tight') monolayer of primary type II pneumocytes in Waymouth medium at a cell density of 0.9x10(6) cells/cm(2); the Calu-3 cells should be grown in DMEM medium containing Hepes at 0.75x10(6) cells/cm(2).     

人胚胎神经干细胞体外培养及其增殖与分化的研究

目的 建立神经干细胞分离、培养及分化的鉴定技术，观察神经干细胞增殖、分化的特点。方法 从人胚胎海马区分离神经干细胞，采用无血清培养基，进行体外扩增培养、传代。采用免疫细胞化学法鉴定神经干细胞和分化的神经细胞；利用流式细胞仪和细胞生长曲线检测神经干细胞的增殖能力。结果 从人胚胎脑海马区分离的细胞具有增殖和多向分化潜能，可进行传代培养，获得的细胞团中大部分为nestin表达阳性细胞。贴壁分化后可以出现NSE、GFAP表达阳性的细胞。结论 用上述方法分离培养的细胞能表达nestin蛋白，具有自我更新和增殖能力，并具有向神经元、星形胶质细胞分化的潜能，具备神经干细胞的特征，可用于细胞移植等相关研究。     

Angiogenesis in vitro: vascular tube formation from the differentiation of neural stem cells

Neural stem cells (NSCs) were isolated from the mouse cortex on embryonic day 12.5 and cultured by neurosphere formation in serum-free medium in the presence of basic fibroblast growth factor (bFGF). When NSCs were inoculated in collagen gels with 10% fetal bovine serum (FBS) and bFGF and incubated for 10 days, vessel-like tube structures consisting of PECAM-1- or VE-cadherin-immunoreactive cells were formed in the gels. Moreover, the formation of vascular tube-like structures with a massive investment of alpha-smooth muscle actin-immunoreactive or GFAP-immunoreactive cells was occasionally observed, indicating angiogenesis identical to cerebral vascular development in vivo. To examine whether NSCs are capable of producing endothelial cells, differentiation was induced by the addition of 10% FBS after bFGF withdrawal. Most of the cells displayed a cobblestone-like morphology. Immunological analyses and RT-PCR indicated that NSCs expressed endothelial cell-specific marker proteins such as PECAM-1, VE-cadherin, and Flk-1; and these expressions were maintained or up-regulated during differentiation. Similar tube structures were also observed when the differentiated cells were inoculated in collagen gels and incubated for 5 days. These results suggested that NSCs give rise to two types of vascular cells, endothelial cells and mural cells in vitro, which have the ability to form vascular tubes.     

碱性成纤维细胞因子对SD大鼠表皮干细胞分化为神经干细胞的影响

目的 研究碱性成纤维细胞因子(bFGF)对大鼠表皮干细胞分化为神经细胞的影响。 方法 分离获得饲养了1~3天的新生SD大鼠表皮基底层组织,利用10 min快速贴壁法消化、分离获得表皮干细胞,于倒置显微镜下观察表皮干细胞的形态。培养表皮干细胞的培养基为K-SFM,然后按照不同密度表皮干细胞进行分组处理(0.1×10⁷/mL,0.3×10⁷/mL,0.5×10⁷/mL,0.1×10⁶/mL),每组加入20 ng/mL的bFGF,利用细胞免疫组织化学法检测细胞标志物Nestin和NSE的变化,以及观察细胞形态发生的变化。 结果 成功分离得到SD大鼠表皮干细胞;bFGF诱导后,0.3×10⁷/mL组和0.1×10⁷/mL组细胞第3天即可见细胞开始伸展生长,在约1周时细胞开始分化成神经细胞;且在细胞形态发生双极化改变的数目趋势上也具有一致性;Nestin和NSE检测均呈阳性表达。     

新生小鼠神经干细胞体外培养、分化及鉴定

目的 简化神经干细胞原代培养的取材及步骤,明确体外定向诱导分化条件,为进一步神经干细胞移植相关实验提供基础条件。方法 新生24 h昆明种小鼠无菌条件下冰上取大脑组织,经机械分离加胰酶消化吹打后,加入含有碱性成纤维细胞生长因子、表皮细胞生长因子和B27的DMEM/F12培养基中培养;加入不同浓度胎牛血清诱导其分化,应用免疫荧光技术行巢蛋白、胶质纤维酸性蛋白、微管相关蛋白2染色,对培养细胞鉴定。结果 新生小鼠提取神经干细胞可形成神经球,并稳定增殖传代,经诱导可定向分化为神经元及星形胶质细胞。结论 新生小鼠较胎鼠取材简单,可培养高质量神经干细胞,血清浓度同向星型胶质细胞方向的分化概率呈正相关。     

Diclofenac inhibits proliferation and differentiation of neural stem cells

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used in clinical situations as anti-inflammatory, analgesic and antipyretic drugs. However, it is still unknown whether NSAIDs have effects on the development of the central nervous system. In the present study, we investigated the effects of NSAIDs on neural stem cell (NSC) proliferation and differentiation into neurons. In contrast to aspirin, naproxen, indomethacin and ibuprofen, treatment with diclofenac (10 microM) for 2 days induced the death of NSCs in a concentration-dependent manner. Diclofenac also inhibited the proliferation of NSCs and their differentiation into neurons. Treatment with diclofenac resulted in nuclear condensation (a morphological change due to apoptosis of NSCs) 24hr after the treatment and activated caspase-3 after 6 hr, indicating that diclofenac may cause apoptosis of neuronal cells via activation of the caspase cascade. These results suggest that diclofenac may affect the development of the central nervous system.     

不同细胞因子体外诱导神经干细胞向神经细胞分化的研究

目的观察碱性纤维母细胞生长因子、白血病抑制因子、脑源性神经营养因子及不同组合对成年SD大鼠脑神经干细胞在体外分化为神经细胞的作用。方法用含碱性纤维母细胞生长因子（bFGF）、B27的无血清细胞培养技术体外培养成年SD大鼠脑神经干细胞,单细胞克隆后行Nestin免疫细胞化学染色;根据培养液中所加营养因子的不同将单细胞克隆传代细胞分为5组培养：bFGF、LIF、BDNF、bFGF＋LIF、bFGF＋BDNF组,此5组细胞培养1周,进行NSE免疫细胞化学染色,计数阳性细胞比例后进行统计学分析。结果单细胞克隆培养后克隆球细胞表达Nestin;与bFGF组、LIF组、BDNF组相比,bFGF＋BDNF组和bFGF＋LIF组神经干细胞分化为神经细胞的比例较高（P〈0．01）,其中bFGF＋BDNF组神经细胞的比例最高。结论在bFGF培养条件下,BDNF促进成年SD大鼠脑神经干细胞向神经细胞分化的能力高于LIF。     

双嘧达莫对体外培养神经干细胞增殖的影响

目的研究双嘧达莫(dipyridamole)对体外培养神经干细胞的促增殖作用.方法取新生小鼠大脑进行神经干细胞原代培养,通过神经球生成的观察、特异性蛋白质免疫细胞化学染色和BrdU标记鉴定并判断其增殖能力;双嘧达莫按0.1,0.5,2.5 μmol·L-13个浓度加入神经干细胞培养基中,同时设立溶媒对照组和阳性对照组,通过观察神经球形态、神经球生成数目及MTT法定量比较,分析不同浓度双嘧达莫对神经干细胞分裂增殖的影响.结果在培养物中有大量神经球生成,神经干细胞的特异性蛋白质免疫细胞化学染色呈阳性,BrdU标记亦呈阳性反应,表明所培养的细胞为神经干细胞,具有增殖能力.双嘧达莫中、高浓度组神经球数目、MTT比色结果明显高于溶媒对照组.结论双嘧达莫具有促进神经干细胞增殖的作用.     

神经干细胞提取及培养方法的体会

神经干细胞提取及体外培养的方法有多种, 但采用不同方法所得到的神经干细胞的活力与稳定性均不同。通过对提取和体外培养SD胎鼠大脑皮质神经干细胞的过程进行思考, 总结出神经干细胞的提取步骤、 提取要点、 培养基的选择依据、 接种密度的选择、 培养方法、 换液方法、 传代时机、 传代方法, 最终获得大量活力和稳定性均较高的神经干细胞, 并将其应用于相关方面的基础研究。     

体外培养海马神经干细胞分化前后离子通道检测

目的:研究神经干细胞(NSCs)分化前后电压依赖性Na 、K 、Ca2 通道的变化。方法:应用全细胞膜片钳技术检测NSCs分化前及分化后3d、7d、14d、21d电压依赖性Na 电流(INa)、延迟整流性K 电流(IK)、电压依赖性Ca2 电流(ICa)。结果: 分化前后均未检出INa,分化前未检出IK,分化后3d、7d、14d、21d,IK检出率分别为11.76%、24.75%、46.51%、76.18%,ICa在分化前后均可检出,分化前和分化后各时间点ICa的幅度分别为(119±73)pA、(213±98)pA、(324±151)pA、(735±312)pA、(1079±307)pA。结论:分化前后均未检出INa,随分化时间延长,IK检出率逐渐增加,ICa幅度逐渐增高。     

Automation of an in vitro cytotoxicity assay used to estimate starting doses in acute oral systemic toxicity tests

Application of High Throughput Screening (HTS) to the regulatory safety assessment of chemicals is still in its infancy but shows great promise in terms of facilitating better understanding of toxicological modes-of-action, reducing the reliance on animal testing, and allowing more data-poor chemicals to be assessed at a reasonable cost. To promote the uptake and acceptance of HTS approaches, we describe in a stepwise manner how a well known cytotoxicity assay can be automated to increase throughput while maintaining reliability. Results generated with selected reference chemicals compared very favourably with data obtained from a previous international validation study concerning the prediction of acute systemic toxicity in rodents. The automated assay was then included in a formal ECVAM validation study to determine if the assay could be used for binary classification of chemicals with respect to their acute oral toxicity, using a threshold equivalent to a dose of 2000 mg/kg b.w. in a rodent bioassay (LD50). This involved the blind-testing of 56 reference chemicals on the HTS platform to produce concentration–response and IC50 data. Finally, the assay was adapted to a format more suited to higher throughput testing without compromising the quality of the data obtained.     

NT-3高表达促进神经干细胞向胆碱能神经元分化

目的体外研究神经营养因子3(neurotrophin-3,NT-3)基因转染神经干细胞(neural stem cells,NSCs)后对其向胆碱能神经元分化的影响,并探讨其机制。方法体外分离培养新生小鼠脑源NSCs,免疫荧光细胞化学法对其进行鉴定;将NSCs分为NSCs组(不作任何处理的NSCs)、GFP-NSCs组(转染GFP的NSCs)、NT-3-NSCs组(转染NT-3的NSCs),免疫荧光细胞化学法和ELISA法检测各组NSCs中NT-3的表达;免疫荧光细胞化学法和RT-PCR法检测各组NSCs向胆碱能神经元分化的能力;乙酰胆碱检测试剂盒检测乙酰胆碱分泌情况;RT-PCR法检测Notch信号通路相关靶基因Hes1、Mash 1和Neurogenin 1(Ngn1)表达情况。结果免疫荧光细胞化学法结果显示,NSCs表达其特异性标志蛋白Nestin和Sox2,与NSCs组和GFP-NSCs组相比,NT-3-NSCs组能够分化为更多的胆碱能神经元(P<0.01),分化的胆碱能神经元可分泌乙酰胆碱(P<0.01),且能够减少Notch通路靶基因Hes 1 mRNA的表达,增加Mash1、Ngn 1 mRNA的表达(P<0.05)。结论 NT-3高表达可促进NSCs分化为更多的胆碱能神经元,其机制可能与抑制Notch信号通路有关。     

Defined culture medium for stem cell differentiation: Applicability of serum-free conditions in the mouse embryonic stem cell test

The embryonic stem cell test (EST) is a validated method to assess the developmental toxicity potency of chemicals. It was developed to reduce animal use and allow faster testing for hazard assessment. The cells used in this method are maintained and differentiated in media containing foetal calf serum. This animal product is of considerable variation in quality, and individual batches require extensive testing for their applicability in the EST. Moreover, its production involves a large number of foetuses and possible animal suffering. We demonstrate the serum-free medium and feeder cell-free maintenance of the mouse embryonic stem cell line D3 and investigate the use of specific growth factors for induction of cardiac differentiation. Using a combination of bone morphogenetic protein-2, bone morphogenetic protein-4, activin A and ascorbic acid, embryoid bodies efficiently differentiated into contracting myocardium. Additionally, examining levels of intracellular marker proteins by flow cytometry not only confirmed differentiation into cardiomyocytes, but demonstrated significant differentiation into neuronal cells in the same time frame. Thus, this approach might allow for simultaneous detection of developmental effects on both early mesodermal and neuroectodermal differentiation. The serum-free conditions for maintenance and differentiation of D3 cells described here enhance the transferability and standardisation and hence the performance of the EST.     

全反式视黄酸促进胚胎神经干细胞诱导分化的研究

目的本研究观察全反式视黄酸（atRA）对于体外分离培养的胚胎神经干细胞（ENSCs）生长增殖和诱导分化的作用及其可能的分子机制。方法分离培养孕15dSD大鼠（E15 d SD Rattus）海马回ENSCs,采用不同组合成分的神经干细胞培养基培养ENSCs,利用MTF法检测其对于ENSCs存活和增殖的影响;采用不同组合成分的神经细胞诱导分化培养基培养ENSCs,利用细胞免疫荧光染色法鉴定ENSCs及atRA对于其诱导分化的影响。结果MTT实验结果表明,atRA^＋组、atRA^-组和DMSO组均出现ENSCs的增殖效果,而对照组则没有明显的增殖现象,其中atRA^-组最明显,DMSO组次之,atRA^＋组最弱。AtRA^＋组与atRA^-的ENSCs经过诱导分化后产生的神经细胞类型有较明显差异,并且atRA组处理产生的神经元是对照组的3倍左右。结论atRA能够抑制ENSCs的增殖,并且抵消神经生长因子对于ENSCs的促进有丝分裂作用,atRA还可以促进ENSCs定向诱导分化为神经元。     

肝细胞生长因子促进神经干细胞向神经元细胞方向的分化

目的观察肝细胞生长因子(HGF)对神经干细胞向神经元细胞方向分化的作用。方法取孕14~17d的胚胎大鼠,分离其脑组织,以无血清培养基培养,得到神经干细胞后,加入HGF诱导其定向分化,以免疫细胞化学和流式细胞术的方法来鉴定分化得到的神经元细胞及其比例。结果加入HGF和胎牛血清(FBS)的实验组镜下神经元细胞较仅加入胎牛血清的对照组多,流式细胞术计数分化成神经元细胞的比例为55·76%,而对照组阳性率为32·69%;镜下直接计数实验组NSE阳性神经元的比例为(53·34±2·81)%,而对照组仅(30·78±3·13)%(P<0·05)。结论HGF具有促进神经干细胞向神经元细胞方向分化的作用。     

成人骨髓间充质干细胞多向分化潜能特性

目的 探讨体外不同诱导条件下成人骨髓间充质干细胞(MSCs)向成骨细胞、脂肪细胞分化的能力.方法 采用地塞米松、胰岛素、β-磷酸甘油、抗坏血酸等诱导培养液对体外分离培养的成人骨髓MSCs进行成骨细胞及脂肪细胞的定向诱导并进行鉴定.结果 成人骨髓MSCs向成骨细胞诱导后可见钙盐分泌,茜素S与钙盐结合成红色,四环素标记后可见到黄色发光的钙化结节;而向脂肪细胞诱导后则可见含有多量脂滴的脂肪细胞,苏丹Ⅳ染色脂滴呈红色,苏木精染色细胞核呈蓝色.结论 成人骨髓MSCs在体外一定条件下可以诱导分化为成骨细胞和脂肪细胞,具有多向分化潜能.     

光电成像系统在评价胚胎干细胞体外定向分化为心肌细胞中的应用

目的采用简易光电成像系统记录胚胎干细胞(ES细胞)体外定向分化心肌细胞的搏动频率,为药物诱导ES细胞体外定向分化心肌细胞提供量化评价指标。方法以简易光电成像系统记录心肌细胞搏动频率,并以维A酸和淫羊藿苷诱导ES细胞定向分化心肌细胞为例,收集分化过程中发育依赖性基因(α-肌球蛋白重链、心室肌球蛋白轻链及β-肾上腺素受体)和心肌特异性蛋白(α-辅肌动蛋白和肌钙蛋白T)表达情况,同步分析光电成像信号与分子生物学指标的一致性。结果光电成像系统可灵敏反映分化心肌细胞的搏动频率,在与维A酸和淫羊藿苷共培养体系中,搏动频率与心肌发育依赖性基因、蛋白表达和β-肾上腺素受体形成等一致,可体现心肌分化的不同时间段。结论简易光电成像系统能灵敏记录ES细胞定向分化心肌细胞的搏动频率,此搏动频率与细胞分化成熟程度一致,可望成为药物诱导分化心肌细胞初步评价的量化指标。     

人胚神经干细胞分离培养与鉴定方法

目的:建立神经干细胞(NSCs)实验室分离、培养方法,为NSCs移植提供细胞源.方法:取4月龄(±15 天)正常孕妇水囊引产胎儿大脑纹状体区组织分离神经干细胞,培养于含碱性成纤维细胞生长因子(bFGF)和B27的无血清培养基;同时利用单细胞克隆技术进行连续传代培养;利用形态学观察和免疫荧光技术检测神经上皮干细胞蛋白Nestin抗原的表达来鉴定神经干细胞.结果:体外培养的干细胞在bFGF和B27培养基中可不断增殖形成细胞球,并出现少量细胞分化.单细胞培养4天即开始分裂,同时伴有个别细胞分化;出现大量神经球一般为15天;分化的细胞在30天开始分解,50天左右基本消失.细胞培养3个月(每月补液1次)仍具有分裂增殖能力.单细胞克隆可连续传代10次,仍具增殖分化能力.液氮冻存6个月的细胞复苏后仍具增殖分化能力.单细胞克隆传代增殖的细胞球经Nestin免疫荧光鉴定,呈阳性结果,证实其胚胎源性.结论:采用bFGF和B27的无血清培养基能促进神经干细胞连续稳定增殖,并有少量分化,细胞体外培养3个月、克隆连续传代10次情况下的细胞仍具有神经干细胞特性.