Neuropeptide Y stimulates proliferation, migration and differentiation of neural precursors from the subventricular zone in adult mice

The neuropeptide Y (NPY) is widely expressed in the central nervous system and has been shown to stimulate neurogenesis in the hippocampus and the olfactory epithelium. Here, we demonstrate that intracerebroventricular injection of NPY stimulates proliferation of neural precursors in the mice subventricular zone (SVZ), one the most neurogenic areas of the brain. Newly generated neuroblasts migrate through the rostral migratory stream to the olfactory bulb and also directly to the striatum, as evidenced by BrdU labelling and cell phenotyping. Using knock-out mice, specific NPY receptor agonists and antagonists, we report that this neuroproliferative effect is mediated by the Y1 receptor subtype that we found to be highly expressed in the SVZ both at the mRNA and protein levels. Our data suggest that stimulating endogenous SVZ neural stem cells by NPY may be of a potential interest in cell replacement based therapies of neurodegenerative diseases affecting the striatum such as Huntington's disease.     

Biglycan及血管内皮生长因子对结肠癌细胞迁移、侵袭能力的影响及机制

目的:观察biglycan及血管内皮生长因子(vascular endothelial growth factor,VEGF)对结肠癌细胞系HCT116迁移、侵袭能力的影响并探讨其可能的机制。方法:在稳定转染biglycan的结肠癌细胞系HCT116中转染VEGF siRNA,实验设置未转染对照组(mock组)、空载质粒和非特异性干扰片段转染对照组(vector+siRNA-NC组)、biglycan cDNA和非特异性干扰片段转染组(biglycan+siRNA-NC组)以及biglycan cDNA和VEGF siRNA共转染组(biglycan+siRNA-VEGF组)。采用实时荧光定量逆转录聚合酶链反应(RT-PCR)法检测biglycan和VEGF的mRNA表达;采用划痕实验检测细胞的迁移能力;采用Transwell法检测细胞的侵袭能力;采用蛋白质印迹(Western blotting)法检测SNAIL、E-钙黏蛋白(E-cadherin)、波形蛋白(vimentin)、基质金属蛋白酶2(MMP-2)、基质金属蛋白酶-9(MMP-9)的表达;采用明胶酶谱法检测MMP-2、MMP-9的活性。结果:与mock组及vector+siRNA-NC组比较,biglycan+siRNA-NC组细胞的迁移、侵袭能力均显著提高(P0.05),vimentin、MMP-2、MMP-9、SNAIL蛋白的表达水平显著提高,E-cadherin蛋白的表达水平则显著下降(P0.05),MMP-2和MMP-9的活性显著提高(P0.05)。与biglycan+siRNA-NC组比较,biglycan+siRNA-VEGF组细胞的迁移、侵袭能力均显著降低(P0.05),SNAIL、vimentin、MMP-2、MMP-9蛋白的表达水平均显著下降,E-cadherin蛋白的表达水平显著提高(P0.05),MMP-2、MMP-9的活性显著下降(P0.05)。结论:biglycan通过促进VEGF的表达来促进结肠癌细胞系HCT116的迁移和侵袭,下调结肠癌细胞中VEGF的表达可逆转biglycan对HCT116迁移和侵袭的促进作用。     

实验性迷走神经损伤后大鼠胸腺细胞NO表达的变化

[目的]探讨迷走神经损伤对胸腺细胞发育及迁移的影响及NO参与调控的可能机制。[方法]采取颈部右侧迷走神经切断术,对大鼠胸腺组织进行酶组织化学及免疫组织化学双标记,观察NADPH阳性细胞CD4、CD8的表达;不同时间点的大鼠胸腺左、右叶中NADPH阳性细胞分布的特点及数量的变化。[结果]NADPH、CD4或NADPH、CD8双标细胞分布于髓质及小血管周围。右侧迷走神经切断术后,胸腺右叶NADPH阳性细胞先增多后减少;在左叶有代偿现象。[结论]NO阳性细胞中包括不同发育阶段的胸腺细胞;迷走神经损伤影响胸腺细胞发育及输出,其机制可能有NO参与。     

碱性成纤维细胞生长因子对体外培养人牙髓细胞增殖和迁移的影响

目的研究碱性成纤维细胞生长因子（basic fibroblast growth factor,bFGF）对体外培养人牙髓细胞增殖、迁移活性的影响。方法以常规组织块培养法体外获得人牙髓细胞,实验组分别加入终浓度为1.0、5.0、10.0和50.0ng/ml的bFGF,对照组仅加入等量的空白培养基,采用CCK-8法分别测定450nm下各组光吸收度A值,研究bFGF对牙髓细胞增殖活性的影响;应用Transwell小室培养法,研究bFGF对牙髓细胞迁移活性的影响。结果与对照组相比,bFGF在1.0～50.0ng/ml浓度下可促进牙髓细胞的增殖（P〈0.05）,bFGF最低显效浓度为1.0ng/ml,最佳显效浓度为10.0ng/ml。bFGF在1.0～50.0ng/ml浓度下诱导细胞迁移（P〈0.05）。结论 bFGF可诱导体外培养人牙髓细胞的增殖和迁移,在牙髓牙本质复合体修复中可能发挥重要作用。     

bFGF和PDGF-BB对内皮祖细胞分化的内皮样细胞和平滑肌样细胞增殖和迁移的影响

目的探讨内皮祖细胞分化的内皮样和平滑肌样细胞在碱性成纤维生长因子和血小板源生长因子BB作用下的增殖和迁移能力。方法将分离、培养及纯化的内皮祖细胞培养5天后进行分组:对照组、碱性成纤维生长因子组和血小板源长因子BB组。对照组使用20%胎牛血清的DMEM培养基;碱性成纤维生长因子组和血小板源生因子BB组在20%胎牛血清的DMEM培养基中分别添加碱性成纤维生长因子(30μg/L)和血小板源生长因子BB(40μg/L)。免疫荧光染色鉴定内皮祖细胞以及检测内皮祖细胞内皮方向分化标记物CD31和vWF,及平滑肌方向分化标记物α-SMA和Calponin。将分化的内皮样细胞和平滑肌样细胞用MTT法和Transwell小室分别检测其增殖活性和迁移能力。结果与对照组比较,内皮祖细胞经碱性成纤维生长因子或血小板源生长因子BB诱导后呈现较强的内皮细胞(CD31,vWF)或平滑肌细胞(α-SMA,Calponin)的荧光染色,被诱导细胞分别称为内皮样细胞和平滑肌样细胞;碱性成纤维生长因子促进内皮样细胞和血小板源生长因子BB促进平滑肌样细胞增殖的作用在一定范围内具有时间(0～48 h)和浓度(碱性成纤维生长因子:0～16μg/L;血小...     

全反式维甲酸对肝癌细胞HepG2的分化、侵袭迁移的影响

目的:探讨全反式维甲酸(ATRA)对肝癌细胞HepG2的诱导分化作用及侵袭迁移的影响.方法:MTT法测定ATRA对肝癌细胞HepG2的抑制作用;平皿集落形成法检测ATRA对HepG2细胞锚定依赖性生长作用;ELISA法检测ATRA作用前后HepG2 AFP分泌量的变化;RT-PCR检测ATRA对HepG2细胞MMP-9及Nanog的mRNA表达的影响;Western blot检测ATRA对HepG2细胞MMP-9及Nanog蛋白表达的影响;Transwell及划痕实验检测其对侵袭及迁移能力的影响.结果:MTT法显示ATRA抑制体外培养人肝癌细胞HepG2细胞生长,呈剂量和时间依赖性;ELISA显示ATRA诱导HepG2细胞分化和凋亡,使代表肝细胞恶变的AFP分泌量明显下降(P<0.05);平皿克隆形成实验结果表明未经ATRA处理的HepG2可形成克隆,但经ATRA刺激后,其形成克隆变小且数目明显减少;ATRA呈时间及浓度依赖性下调Nanog mRNA及蛋白的表达,并在24h呈浓度依赖性下调MMP-9 mRNA及蛋白表达;Transwell实验和划痕实验结果显示ATRA能抑制HepG2细胞的侵袭和迁移能力.结论...     

反式载脂蛋白A1模拟肽R-D4F对内皮祖细胞黏附及迁移功能的影响

目的探讨反式载脂蛋白A1模拟肽R-D4F对人内皮祖细胞黏附及迁移功能的影响。方法取新鲜人脐静脉血,采用密度梯法从中分离、诱导培养人内皮祖细胞,并使用Dil-ac-LDL和FITC-UEA-1染料进行双荧光染色以及流式细胞术进行鉴定。分别给于牛血清白蛋白、顺式D-4F(50μg/ml)及R-D4F(5~50μg/ml)处理后,采用黏附能力测定实验及Transwell小室观察内皮祖细胞黏附及迁移能力的变化。结果与牛血清白蛋白对照组相比,D-4F显著增强内皮祖细胞的黏附及迁移功能。相似的是,R-D4F呈剂量依赖性地增强内皮祖细胞的黏附与迁移。结论 R-D4F具有与D-4F相似的生物学作用,可促进人内皮祖细胞的黏附及迁移。     

Alcohol Modulation of Human Normal T-Cell Activation, Maturation, and Migration

We are interested in the characterization of the effects of alcohol on human T-cell activation, maturation, and migration, because this cell population is crucial in the initiation, regulation, and propagation of cellular immunity. We and others have described the effects of both acute and chronic exposure of human immune cells to ethanol (EtOH) in vitro. Herein, we briefly, review these reports and expand this body of literature with the inclusion of new data recently obtained in our laboratory. We confirm the blunting effects of EtOH on the production of interleukin-2 and mitogen proliferative response following T-cell mitogen stimulation, and on the expression of membrane markers of activation. We show that EtOH significantly alters the expression of the CD4 cell-associated marker of activation, CD26. We report the effect of EtOH on the expression of the homing receptor CD62L by CD4⁺ cells, and on their ability to adhere by a CD18-mediated process to a defined cellular substratum. Furthermore, we demonstrate the effects of EtOH and EtOH and 0-endor-phin pretreatment on the activation of CD4⁺ lymphocytes endowed with the homing receptor CD62L.