脑微血管内皮细胞和脑肿瘤干细胞共培养的体外实验研究

目的 研究体外培养条件下,脑微血管内皮细胞(brain microvascular endothelial cells,BMECs)对脑肿瘤干细胞(braintumor stem cells,BTSCs)增殖、自我更新及分化功能的影响.方法 应用Transwell小室建立BMECs与BTSCs共培养模型,并建立对照组,共培养14 d后,测量肿瘤球(brain tumor sphere,BTS)直径大小,检测BTSCs增殖曲线,测定单细胞克隆形成率.在含血清的培养基中培养10 d后,行CD133、Nestin、GFAP、DAPI免疫荧光染色,计数两组的CD133、Nestin、GFAP染色的细胞数及同一视野的DAPI染色细胞核数,观察两组之间的差异.结果 共培养组BTS直径是对照组的5.05倍,增殖快,共培养组有61.4%能形成下一代BTSCs,而对照组为39.0%.在含血清的培养基中培养10 d后,共培养组的GFAP阳性率较对照组低,而CD133、Nestin阳性率较对照组高.结论 BMECs能够促进BTSCs增殖、自我更新能力,保持BTSCs未分化状态.     

蒙成药扎冲十三味丸对大鼠脑缺血组织细胞凋亡的影响

目的 探讨扎冲十三味丸对缺血性脑组织损伤的保护机制.方法 利用线栓法制作大鼠大脑中动脉闭塞模型,采用Elisa法和流式细胞技术Annexin V fitc/pi细胞双染法,检测凋亡细胞相关蛋白和神经细胞凋亡百分率,观察扎冲十三味丸对脑缺血组织bcl-2和bax蛋白表达水平以及缺血组织细胞凋亡程度的影响.结果 扎冲十三味丸能减低缺血脑组织Bax蛋白含量和上调Bcl-2蛋白含量以及降低缺血脑组织细胞凋亡百分率.结论 扎冲十三味丸通过降低缺血脑组织细胞凋亡百分率,对脑组织缺血损伤有保护作用.     

Effects of barbiturates on hypoxic cultures of brain derived microvascular endothelial cells

An in vitro model of the blood-brain barrier (BBB) consisting of porcine brain derived microvascular endothelial cells (BMEC) seeded onto collagen-coated polycarbonate membranes was used to investigate the effects of the barbiturates, methohexital and thiopental, on permeability properties of the endothelial cell monolayer under hypoxia. The permeability of cultured BMEC to ions and sucrose increased significantly during 6 h of hypoxia in a reversible manner. Cells were resistant to hypoxia for up to 24 h, but 48 h resulted in marked damage as assessed by the release of lactate dehydrogenase activity into the culture medium. The hypoxia-induced increase of the permeability was unchanged in the presence of superoxide dismutase (SOD) and catalase. Methohexital and thiopental decreased the hypoxia-induced permeability increase in a concentration-dependent manner and permeability changes were abolished completely at the barbiturate concentration of 50, μg/ml. The barbiturates had no effect on the intracellular cAMP content which started to decline after 3 h of hypoxia. Results suggest that barbiturates at high concentrations might be able to prevent permeability changes of the BBB during cerebral ischemia.     

西洛他唑对糖氧剥离大鼠脑微血管内皮细胞的保护作用

目的探讨磷酸二酯酶(PDE)3抑制剂西洛他唑对大鼠脑微血管内皮细胞糖氧剥离损伤的影响及作用机制。方法原代培养大鼠皮层微血管内皮细胞,建立糖氧剥离细胞模型模拟"缺血"过程,分5组:正常对照组、西洛他唑组、依达拉奉组、溶剂对照组、模型组。糖氧剥离6h后,测定细胞上清中内皮型一氧化氮合酶(eNOS)和诱导型一氧化氮合酶(iNOS)水平、细胞内环磷腺苷酸(cAMP)浓度,及采用四唑盐(MTT)比色实验测定细胞活力。结果西洛他唑及依达拉奉均可明显提高缺血细胞模型上清中eNOS水平,同时降低iNOS水平,提高细胞内cAMP水平及细胞存活率(均P0.05),且西洛他唑作用更为显著。结论西洛他唑对培养大鼠皮层微血管内皮细胞在缺血损伤中具有保护作用,其作用机制可能是通过选择性抑制PDE3从而增加cAMP水平,间接增加eNOS水平、降低iNOS水平来实现的。     

Organic anion transporting polypeptide 2 transports valproic acid in rat brain microvascular endothelial cells

Objectives: Abnormal drug transporter expression or function in the brain may lead to decreased concentrations of antiepileptic drugs (AEDs) in the central nervous system in patients with drug-resistant epilepsy. We previously showed the influx transporter organic anion transport polypeptide 2 (Oatp2) was expressed in rat brain microvascular endothelial cells (BMECs). Seizures decrease expression of Oatp2, but it remains unclear whether Oatp2 transports AEDs. In this study, we utilized rat BMECs as an in vitro model of the blood–brain barrier (BBB) to study Oatp2-mediated transport of valproic acid (VPA), the most common clinically used AEDs.

Methods: In vivo injection of pregnenolone-16-carbonitrile was used to induce high expression of Oatp2 in isolated BMECs. Small interfering RNA treatment was used to silence Oatp2, and uptake of VPA was assessed.

Results: Increased expression of Oatp2 in BMECs increased the uptake of VPA, while inhibition of Oatp2 reduced VPA uptake.

Discussion: This study indicates Oatp2 transports VPA across the BBB, and suggests altered Oatp2 expression may contribute to resistance to VPA in patients with drug-resistant epilepsy.     

木香烃内酯通过调控LncRNA LINC01116/miR-9-5p的表达来减轻过氧化氢诱导的大鼠脑微血管内皮细胞损伤

目的 探讨木香烃内酯(Cos)对过氧化氢(H₂O₂)诱导的大鼠脑微血管内皮细胞的氧化应激、凋亡的影响及其对长链非编码RNA LINC01116(LncRNA LINC01116)/微小RNA-9-5p(miR-9-5p)的调控作用。方法 原代分离培养大鼠脑微血管内皮细胞,并随机分成Con组、H₂O₂组、Cos-L组、Cos-M组、Cos-H组、Cos-H+pcDNA组、Cos-H+pcDNA-LINC01116组; 采用化学比色法检测丙二醛(MDA)、还原型谷胱甘肽(GSH)的水平及超氧化物歧化酶(SOD)的活性; 流式细胞术检测细胞凋亡率; 实时荧光定量聚合酶链反应(qRT-PCR)检测LINC01116、miR-9-5p的表达水平; 双荧光素酶报告实验验证LINC01116与miR-9-5p的靶向关系; 蛋白免疫印迹法(Western blot)检测B淋巴细胞瘤-2相关蛋白(Bax)、B淋巴细胞瘤-2(Bcl-2)的表达水平。结果 H₂O₂处理后MDA的水平显著升高(P<0.05),GSH水平与SOD活性显著降低(P<0.05),细胞凋亡率显著升高(P<0.05),Bax蛋白水平显著升高(P<0.05),Bcl-2蛋白水平显著降低(P<0.05),LINC01116的表达水平显著升高(P<0.05),miR-9-5p的表达水平显著降低(P<0.05); Cos处理后MDA的水平显著降低(P<0.05),GSH水平与SOD活性显著升高(P<0.05),细胞凋亡率显著降低(P<0.05),Bax蛋白水平显著降低(P<0.05),Bcl-2蛋白水平显著升高(P<0.05),LINC01116的表达水平显著降低(P<0.05),miR-9-5p的表达水平显著升高(P<0.05),且Cos-L组、Cos-M组、Cos-H组上述指标的水平比较均有明显差异(P<0.05); 双荧光素酶报告实验证实LINC01116可靶向结合miR-9-5p; LINC01116过表达可减弱木香烃内酯对H₂O₂诱导的大鼠脑微血管内皮细胞凋亡及氧化应激的作用。结论 木香烃内酯可能通过抑制LINC01116的表达及促进miR-9-5p的表达来抑制H₂O₂诱导的大鼠脑微血管内皮细胞的氧化应激及细胞凋亡,从而减轻细胞损伤。     

Hypoxia-induced changes in tight junction permeability of brain capillary endothelial cells are associated with IL-1beta and nitric oxide

We examined whether hypoxia alone could produce changes in the permeability of brain capillary endothelial cells (EC) and whether a stimulation of hypoxic status alters the gene expression of occludin and glucose transporter 1 (GLUT1). Exposure of EC to hypoxia resulted in increased permeability, with the greatest decrease in transendothelial electrical resistance (TER) at 40 h. Moreover, hypoxia alone induced the expression of both mRNA in EC. Furthermore, we found that interleukin-1 (IL-1)beta, glutamate, hydrogen peroxide (H2O2), and sodium nitroprusside (SNP) induced the expression of mRNA for occludin and GULT1 under normoxic condition. The decrease in TER due to hypoxia was inhibited on addition of an anti-IL1 antibody and nitric oxide synthase (NOS) inhibitor in EC. These results indicate that the expression of occludin and GLUT1 mRNA is sensitive to exposure to hypoxia and that the changes of permeability in EC are associated with IL-1beta and NO.     

降纤酶对大鼠局灶性脑缺血血管内皮细胞超微结构及内皮细胞凋亡的影响

目的 探讨降纤酶对缺血性脑水肿病理过程中血脑屏障（BBB）内皮细胞的保护作用以及其对内皮细胞凋亡的影响。方法 选用Wistar雄性大鼠42只，体重250－300g，鼠龄3－4个月，随机分成降纤酶组、盐水对照组和假手术组，参考Longa等方法建立大鼠大脑缺血动物模型，彩和电观察大鼠BBB的超微结构和TUNEL试剂盒检测内皮细胞的凋亡。结果 通过电镜观察发现降纤酶组的毛细血管内皮细胞膜完整，水肿较轻，其损伤程度明显较对照组轻。降纤酶组在缺血6h和缺血24h随缺血时间延长缺血中心区凋亡细胞数量减少，而缺血半影区凋亡细胞数量增加，其凋讯细胞数量明显少于盐水对照组同一时期值。结论 降纤酶对脑缺血的血管内皮细胞及BBB具有明显的保护作用。     

Murine cytomegalovirus induces apoptosis in non-infected cells of the developing mouse brain and blocks apoptosis in primary neuronal culture

Cytomegalovirus (CMV) is the most common cause of congenital infection, resulting in birth defects such as microcephaly. In this study, we found that apoptosis is induced in the developing mouse brain infected with murine cytomegalovirus (MCMV) in an association with neuronal cell loss. With the combination of the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) technique and immunohistochemical staining, 3.8% of the TUNEL-positive cells were double-stained with the antibody to neuron-specific enolase, while none of the TUNEL-positive cells were stained with antibodies to the immediate early and early viral antigens of MCMV. Furthermore, distribution pattern of the TUNEL-positive cells was different from that of viral DNA-positive cells detected by the in situ DNA-DNA hybridization. More than 30% of the TUNEL-positive cells were double-stained with the F4/80 antibody specific for microglia/macrophages, which were sometimes swollen, presumably the consequence of engulfment of the neuronal apoptotic cells. In the primary neuronal cultures, MCMV infection inhibited the induction of apoptosis either by serum deprivation or by glutamate treatment. It was also confirmed by the double-staining method that apoptosis was not induced in the viral-infected neuronal cultures. These results suggest that MCMV infection induces apoptosis in non-infected neuronal cells, presumably by indirect mechanisms, and that apoptotic cells are engulfed by microglia/macrophages. The induction and blocking of neuronal apoptosis by viral infection may be important for morphological and functional brain disorders in the congenital CMV infection. Received: 30 December 1997 / Revised, accepted: 3 March 1998     

tMfn2基因诱导血管平滑肌细胞的凋亡

背景: 线粒体融合素2蛋白,主要通过磷脂酰肌醇3激酶/蛋白激酶B诱导血管平滑肌细胞凋亡。去除穿膜区序列的线粒体融合素2蛋白,相对分子质量减小41%,诱导凋亡作用可能更强。 目的：观察比较去除穿膜区序列的大鼠线粒体融合素基因2对大鼠血管平滑肌细胞凋亡的影响及其相关的信号通路。　 设计、时间及地点：基因水平的对比观察实验。于2008-01/10在华中科技大学同济医学院附属同济医院分子心脏病中心实验室完成。 材料：大鼠血管平滑肌细胞及携带半乳糖甘酶基因、携带线粒体融合素2基因和携带去除穿膜区序列线粒体融合素2基因的重组腺病毒均由陈光慧教授惠赠。 方法：将大鼠血管平滑肌细胞传代培养3~10代后随机分为4组,①空白对照组：不加干预。②携带半乳糖甘酶基因的对照组：感染携带半乳糖甘酶基因的重组腺病毒。③携带线粒体融合素2基因的实验组：感染携带线粒体融合素2基因的重组腺病毒。④携带去除穿膜区序列线粒体融合素2基因的实验组：感染携带去除穿膜区序列线粒体融合素2基因的重组腺病毒。 主要观察指标：①重组腺病毒感染血管平滑肌细胞24 h后观察完整的和去除穿膜区序列的线粒体融合素2基因的表达情况。②感染后24,48和72 h采用流式细胞术、酶联免疫吸附法观察细胞凋亡情况。③免疫印迹分析病毒感染血管平滑肌细胞24 h后磷酸化蛋白激酶B表达变化。 结果：①感染后完整的和去除穿膜区序列的线粒体融合素2基因在血管平滑肌细胞中均有表达。②去除穿膜区序列的线粒体融合素2基因诱导血管平滑肌细胞凋亡的作用显著增强,且呈时间依赖性(P < 0.01)。③两个实验组中磷酸化蛋白激酶B水平均明显降低,但去除穿膜区序列的线粒体融合素2基因实验组更显著(P < 0.01)。　 结论：去除穿膜区序列的线粒体融合素基因2诱导血管平滑肌细胞凋亡的作用更强,其机制与抑制蛋白激酶B磷酸化有关。     

原代大鼠脑毛细血管内皮细胞培养与鉴定简

目的介绍一种从大鼠脑组织中分离培养原代大鼠脑血管内皮细胞（BCEC）的方法。方法采用酶消化、滤网机械分离结合右旋糖苷密度离心的方法分离脑毛细血管段,接种在涂有明胶的培养皿培养BCEC。结果通过环境扫描电镜观察细胞形态,量子点超敏细胞免疫荧光鉴定,我们培养出来了纯度较高的原代BCEC。结论将分离的鼠脑毛细血管段置于涂有明胶的培养皿上培养原代BCEC的新方法比传统的培养法可以得到纯度更高的BCEC,为后期基于BCEC为载体的动物实验奠定了细胞基础。     

慢性低氧对小鼠脑微血管内皮细胞RAGE和LRP-1表达的影响

目的研究慢性低氧状态下血脑屏障上β淀粉样蛋白（amyloidD，Aβ）转运体——晚期糖基化终产物受体（RAGE）及低密度脂蛋白受体相关蛋白-1（LRP-1）表达的变化。方法将鼠脑微血管内皮细胞（BMVECs）分别进行正常气体培养（正常对照组）以及24h、36h及48h的低氧培养，用RT—PCR法和WesternBlot法分别检测细胞RAGE和LRP-1mRNA和蛋白的表达。结果低氧24h组RAGEmRNA和蛋白表达低于正常对照组（P〈0．05），低氧48h组RAGEmRNA和蛋白表达高于正常对照组（P〈O．05），低氧24h、36h及48h组RAGEmRNA和蛋白表达呈时间依赖性增高（P〈0．05）；低氧各组LRP-1mRNA和蛋白表达较正常对照组降低，呈时间依赖性（P〈0．05）；RAGE／LRP，1mRNA和蛋白表达呈时间依赖性增高（P〈0．05）。结论在慢性低氧状态下，血脑屏障BMVECs表达RAGE上调，LRP-1下调，RAGE／LRP-1比值增高，推测可能由此增加了Ap的净入脑量。     

Glycosphingolipid composition of primary cultured human brain microvascular endothelial cells

Glycosphingolipid (GSL) antigens have been considered to be involved in the pathogenesis of autoimmune neurologic disorders including multiple sclerosis. To establish the GSL pattern specific for endothelial cells forming blood-brain barrier (BBB), we established a method to yield sufficient quantities of highly purified human brain microvascular endothelial cells (HBMECs) and compared their GSL composition to that of human umbilical cord vein endothelial cells (HUVECs), as the representative of endothelial cells not forming BBB. The major gangliosides were GM3 and sialyl paragloboside (LM1), and the major neutral GSLs were lactosylceramide (LacCer), globotriaosylceramide (Gb3), and globoside (Gb4). Trace amounts of GM1, GD1a, GD1b, GT1b, and sulfoglucuronosyl paragloboside (SGPG) could be detected by the high performance thin layer chromatography-overlay method. SGPG was detected only at a nonconfluent state in an amount almost 1/30 that of in nonconfluent HUVECs. Conversely, GM3 and LM1 increased significantly after confluency. The amount of Gb3 in HBMECs was almost as twice that in HUVECs. The significance of these differences in GSL content between HBMECs and HUVECs and between confluent and nonconfluent states is obscure. It might be related, however, to the defense mechanism at the BBB and to the susceptibility of the central nervous system in some disorders that target cell surface GSL, such as hemolytic uremic syndrome.     

In vitro intercellular adhesion molecule-1 expression on brain endothelial cells in multiple sclerosis

To investigate the origin of intercellular adhesion molecule-1 (ICAM-1) and its expression on brain endothelial cells, we studied the expression in vitro of ICAM-1 on human brain endothelial cells after incubation of T cells from patients with multiple sclerosis (MS) using a histochemical technique and flow cytometry. We determined soluble forms of ICAM-1 (sICAM-1) in the supernatants after mixtures of brain endothelial cells and T cells from patients with MS using an enzyme-liked immunosorbent assay. Flow cytometric analysis showed that a number of ICAM-1-positive cells were significantly increased after incubation of brain endothelial cells with T cells from patients with acute relapsing MS during an exacerbation as compared with those of controls (P<0.01). Patients with acute relapsing MS during an exacerbation and chronic progressive MS exhibited higher levels of ICAM-1 in the supernatants of mixtures with brain endothelial cells and lymphocytes than those of controls (P<0.001 and P<0.01, respectively). These results suggest that lymphocytes from patients with acute relapsing MS during an exacerbation lead to an increased expression of ICAM-1 on the brain endothelial cells and add to evidence involving this adhesion molecule in the pathogenesis of MS.     

氧合血红蛋白对脑微血管内皮细胞增殖和凋亡的影响

目的 探讨氧合血红蛋白（OxyHb）对体外培养的大鼠脑微血管内皮细胞增殖和凋亡的影响。方法 将原代培养的大鼠脑血管内皮细胞与不同浓度的氧合血红蛋白共孵育,以MTT法检测脑血管内皮细胞的存活率;将氧合血红蛋白与脑血管内皮细胞共培养,以流式细胞仪和Hochest33258荧光染色法检测细胞凋亡的情况。结果 氧合血红蛋白能显著抑制血管内皮细胞的增殖,与对照相比存在统计学意义,能显著诱导血管内皮细胞凋亡。结论 在一定浓度范围内的OxyHb能够明显抑制原代培养的脑血管内皮细胞增殖并引起凋亡,提示SAH后内皮细胞凋亡可能是发生CVS的原因之一。     

大鼠脑微血管内皮细胞的体外培养

目的探讨大鼠脑微血管内皮细胞的培养方法.方法取Wistar大鼠乳鼠脑组织,采用筛网过滤、胶原酶消化、离心等技术获取脑微血管内皮细胞,并进行培养.通过形态学、免疫细胞化学方法进一步鉴定,采用MTT方法测定生长曲线.结果经形态学、免疫细胞化学方法鉴定所培养的细胞为脑微血管内皮细胞,观察到原代脑微血管内皮细胞有3种表型,细胞呈单层生长,并可传代培养.结论建立大鼠脑微血管内皮细胞的培养方法可为体外研究脑血管病提供有益帮助.     

Bilirubin produces apoptosis in cultured bovine brain endothelial cells

Blood components such as oxyhemoglobin are believed to cause cerebral vasospasm by inducing contraction and cell death in cerebral arteries. We have observed previously that oxyhemoglobin produces apoptotic changes in cultured endothelial cells. This study was undertaken to explore if bilirubin, a bi-product of hemoglobin degradation, will produce similar cytotoxicity in endothelial cells. Cultured bovine brain microvascular endothelial cells were incubated in four concentrations of bilirubin (10, 25, 50, and 100 microM) for varying times (6, 12, and 24 h). Control cells were incubated in saline or vehicle (NaOH solution, <0.01% of 0.01 N) for similar time periods. The cultured cells were then observed microscopically for evidence of cellular alterations. Bilirubin (10-100 microM) produced apoptosis that appeared time-dependent but not clearly concentration-dependent. Biochemical markers for apoptosis such as DNA fragmentation and PARP cleavage were induced by bilirubin. We conclude that endothelial cells may undergo apoptosis after exposure to bilirubin.     

抑制磷酸酶和tau过度磷酸化诱导神经细胞凋亡

目的探讨磷酸酶活性抑制、tau蛋白异常磷酸化与神经细胞变性死亡的关系.方法磷酸酶(PP)-2A/PP-1抑制剂岗田酸(okadaicacid,OA)10nmol/L与成神经细胞瘤细胞(SH-SY5Y)共培养,DNA-梯带和末端转移酶标记技术.结果用10nmol/LOA与SY5Y细胞共培养24h和48h均可引起DNA-梯带出现,此时末端转移酶标记显示阳性细胞数由2.16%±0.94%分别增多至18.05%±3.57%(P＜0.01)和22.52%±4.78%(P＜0.01).结论由于上述检测指标均与细胞凋亡有关,提示抑制PP-2A和部分抑制PP-1引起tau蛋白异常磷酸化可能通过神经细胞凋亡而引起AD患者神经细胞丢失.     

辛伐他汀抑制高糖诱导人脐静脉内皮细胞的凋亡

背景：他汀类药物对血管内皮细胞的凋亡是否有影响目前尚不明确。 目的：探讨辛伐他汀对高糖诱导的人脐静脉内皮细胞凋亡的影响。 方法：用DMEM细胞培养液培养人脐静脉内皮细胞,将细胞分成空白对照组、高糖组和高糖+辛伐他汀组,用四甲基偶氮唑蓝比色法测定人脐静脉内皮细胞的存活率,流式细胞仪和Western blot分别检测细胞早期凋亡率及P53蛋白表达。 结果与结论：高糖组及高糖+辛伐他汀组细胞增殖率较空白对照组明显降低(P < 0.01),而高糖组细胞增殖率较高糖+辛伐他汀组亦降低(P < 0.01);高糖组P53蛋白表达量及凋亡率较空白对照组及高糖+辛伐他汀组明显增加(P < 0.01),高糖+辛伐他汀组P53蛋白表达及凋亡率亦明显高于空白对照组(P < 0.01)。表明高糖可通过促进促凋亡蛋白P53的表达进而促进人脐静脉内皮细胞的凋亡,而辛伐他汀可抑制此作用。     

Germanium dioxide induces mitochondria-mediated apoptosis in Neuro-2A cells

Germanium (Ge) is commonly used in the semiconductor industry as well as health-promoting and medical field. Biologically, germanium possesses erythropoietic, anti-microbial, anti-tumor, anti-amyloidosis, and immunomodulative effects. However, toxic effects of Ge-containing compounds on kidney, muscle, neuronal cells, and nerves have been reported. Mitochondrial dysfunction was found to be involved in the pathogenesis of GeO(2)-induced nephropathy and myopathy. Since it is well known that mitochondria play a major role in apoptosis triggered by many stimuli, an effort was made to examine whether the Ge-induced neurotoxicity occurs through mitochondria-mediated apoptosis. A mouse neuroblastoma cell line, Neuro-2A, was used in the present study. After incubating with 0.1-800microM of GeO(2) for 0-72h, the cell viability of Neuro-2A cells was inhibited in a dose- and time-dependent manner. Further analysis showed that aside from the changes in the nuclear morphology responsible for apoptosis, the release of cytochrome c, the loss of mitochondrial membrane potential, the translocation of Bax, and the reduction of Bcl-2 expression were also observed in Neuro-2A cells after GeO(2) treatment. These results indicate that the mitochondria-mediated apoptosis is involved in this in vitro model of GeO(2)-induced neurotoxicity.