白细胞介素—1和阿片肽促进大鼠大脑皮层神经细…

对白细胞介素－１（ＩＬ－１）、脑啡肽、β－内啡肽及即刻早期基因ｃ－ｆｏｓ、ｃ－ｊｕｎ与癫痫发病机理的研究。结果显示ＩＬ－１、ＩＬ－１受体拮抗剂、β－内啡肽、抗β－内啡肽抗血清、亮－脑啡肽（ＬＥ）均能促进大脑皮层神经细胞ｃ－ｆｏｓ、ｃ－ｊｕｎ ｍＲＮＡ表达，但ＩＬ－１受体拮抗剂、抗β－内啡肽抗血清促ｃ－ｆｏｓ、ｃ－ｊｕｎ ｍＲＮＡ表达量明显低于ＩＬ－１、ＬＥ及β－内啡肽的作用，并能部分抑制后者的作用     

白细胞介素－1和阿片肽促进大鼠大脑皮层神经细胞c－fos及c－jun mRNA表达

对白细胞介素－１（ＩＬ－１）、脑啡肽、β－内啡肽及即刻早期基因ｃ－ｆｏｓ、ｃ－ｊｕｎ与癫痫发病机理的研究。结果显示ＩＬ－１、ＩＬ－１受体拮抗剂、β－内啡肽、抗β－内啡肽抗血清、亮－脑啡肽（ＬＥ）均能促进大脑皮层神经细胞ｃ－ｆｏｓ、ｃ－ｊｕｎｍＲＮＡ表达，但ＩＬ－１受体拮抗剂、抗β－内啡肽抗血清促ｃ－ｆｏｓ、ｃ－ｊｕｎｍＲＮＡ表达量明显低于ＩＬ－１、ＬＥ及β－内啡肽的作用，并能部分抑制后者的作用；ＩＬ－１、β－内啡肽、ＬＥ促ｃ－ｆｏｓｍＲＮＡ表达在一定范围呈现量效关系；ＩＬ－１诱导ｃ－ｆｏｓ、ｃ－ｊｕｎｍＲＮＡ表达呈现时间效应关系，均为短暂表达。由于具有不同生物学效应的因子均能诱导不同程度ｃ－ｆｏｓ、ｃ－ｊｕｎｍＲＮＡ表达，提示它们对靶基因的调控具有正性及负性双向性，对神经细胞兴奋性产生不同作用。     

白细胞介素—1β及肿瘤坏死因子—α对脑损伤后胶质细胞c—fos…

本研究用分子杂交技术观察了白细胞介素－１β及肿瘤坏死因子－α对脑损伤后及培养的胶质细胞ｃ－ｆｏｓ ｍＲＮＡ表达的影响。结果发现：脑损伤后损伤周围组织ｃ－ｆｏｓ ｍＲＮＡ表达呈动态变化；１ｈ后增加１７０％，１２ｈ后增加３０％，２４ｈ后增加１３０％。发现白细胞介素－１β和肿瘤坏死因子－α能显著增加脑损伤后１２ｈ及２４ｈ ｃ－ｆｏｓ ｍＲＮＡ的表达；当培养的胶质细胞中加入此二者后１ｈ ｃ－ｆｏｓ ｍＲＮ     

N—氨基—D—门冬氨酸诱导大鼠下丘脑视上核,室旁核和弓状核内c—fo…

实验用ｆｏｓ蛋白免疫组织化学方法，研究了中枢神经系统兴奋性介质Ｎ－氨基－Ｄ－门冬氨酸诱导大鼠下丘脑内ｃ－ｆｏｓ的表达。Ｎ－氨基－Ｄ－门冬氨酸注射大鼠皮下后，观察了ｆｏｓ阳性细胞在下丘脑内开始出现与消失的时程相关以及在下丘脑内的分布，结果表明：给Ｎ－氨基－Ｄ－门冬氨酸后３０发开始出现ｆｏｓ阳性细胞，１￣２小时达高峰，４￣８小时消失，ｆｏｓ阳性细胞主要分布于视上核、室旁核和弓状核，视上核和室旁核中ｆｏ     

表皮生长因子对大鼠血淋巴细胞c—fos基因表达的效应

本研究的目的是探讨表皮生长因子对大鼠血淋巴细胞转化率和ｃ－ｆｏｓ基因表达的效应。结果表明：大鼠血淋巴细胞呈免疫反应性，胞质内可见到ＥＧＦｍＲＮＡ信号；ＥＧＦ瓣育可显著提高大鼠血淋巴细胞的转化率和ｃ－ｆｏｓ基因表达水平，与对照组相比较，Ｐ＜０．００１，而与植物血凝素孵育组无显著性差异，Ｐ＞０．０５。     

原癌基因c-fos、p53及运动神经诱向因子1受体在人早期胎盘绒毛的免疫组织化学定位

为了解原癌基因对胎盘滋养层细胞的影响，用原癌基因ｃ－ｆｏｓ、ｐ５３蛋白的抗体和运动神经诱向因子１（ｍｏｔｏｎｅｕｒｏｎｏｔｒｏｐｈｉｃｆａｃｔｏｒ１，ＭＮＴＦ１）抗独特型抗体的免疫组织化学技术，研究了ｃ－ｆｏｓ、ｐ５３及ＭＮＴＦ１受体在人早期胎盘的分布。人早期胎盘的两类滋养层细胞及绒毛中轴的基质细胞均呈ｃ－ｆｏｓ、ｐ５３免疫反应性，反应产物大部分布于胞核内。在相邻切片上，ｃ－ｆｏｓ免疫反应性细胞同样显示ＭＮＴＦ１受体免疫反应性，其反应物质分布于胞质内。以上结果提示，原癌基因ｃ－ｆｏｓ和ｐ５３可能参与调控绒毛细胞的增殖分化，而且ｃ－ｆｏｓ和ＭＮＴＦ１受体可能有协同调控作用。     

鼻咽鳞癌肿瘤分化与c—fos癌基因表达的关系

探讨鼻咽鳞癌组织与分化与ｃ－ｆｏｓ癌基因的关系。方法；采用免疫组化ＡＢＣ法和图象分析技术检测１２５例鼻咽癌的ｃ－ｆｏｓ癌基因表达产物及共阳性胞核面积。结果；非角化性鳞癌ｃ－ｆｏｓ癌基因阳性率高于角化性鳞癌，前者中低分化鳞癌的未分化癌之间的ｃ－ｆｏｓ阳性率差异没有显著性，而核面积明显增大的未分化泡状癌细胞核未见阳性表达。     

脑创伤组织提取液对培养星形胶质细胞的形态特征及FOS基因…

本研究应用分子杂交和形态学方法观察脑创伤组织提取液对培养大鼠脑星形胶质细胞ｃ－ｆｏｓ原癌基因表达的影响及形态特征改变。发现在分散培养７ｄ后换置于含有脑创伤组织提取液的培养液３０￣６０ｍｉｎ，斑点杂交显示星形胶质细胞ｃ－ｆｏｓ原癌基因表达比加正常脑组织提取液组明显，２ｈ后表达减弱。统计学表明有显著差异。推测损伤因素引起了ｃ－ｆｏｓ原癌基因表达，当将脑创伤组织提取液加入新生鼠星形胶质细胞培养液３ｄ后，     

白细胞介素6诱导小鼠T细胞杂交瘤细胞c－fos基因表达

本文应用Ｎｏｒｔｈｅｒｎｂｌｏｔ和斑点杂交技术，观察了ｒＩＬ－６对ＩＬ－６依赖株小鼠Ｔ细胞杂交瘤细胞ＭＨ６０的ｃ－ｆｏｓ基因表达的诱导作用。结果表明：ｒＩＬ－６可明显诱导ＭＨ６０细胞ｃ－ｆｏｓ基因表达，具有剂量效应关系，且表达程度与ＩＬ－６刺激ＭＨ６０细胞增殖速率相平行，提示ＩＬ－６促肿瘤细胞分裂增殖效应是由活化ｃ－ｆｏｓ基因所介导的。     

原癌基因c—fos,p53及运动神经诱向因子1受体在人早期胎盘绒…

为了解原癌基因对胎盘滋养层细胞的影响，用原癌基因ｃ－ｆｏｓ、ｐ５３蛋白的抗体和运动神经诱向因子抗独特特异抗体的免疫组织化学技术，研究了ｃ－ｆｏｓ、ｐ５３及ＭＦＴＦ１受体在人早期胎盘的分布。人早期胎盘的两类滋养层主绒毛中轴的基质细胞均呈ｃ－ｆｏｓ、ｐ５３免疫反应性，反应产物大部分布于胞核内，在相邻切片上，ｃ－ｆｏｓ免疫反应性细胞同样显示ＭＮＴＦ１受体免疫反应性，其反应物质分布于胞质内。以上结果提示，     

Monoclonal antibody (EGR/G49) reactive with the epidermal growth factor receptor of A431 cells recognizes the blood group ALeb and ALey structures

The carbohydrate specificity of the monoclonal antibody EGR/G49, raised against the epidermal growth factor (EGF) receptor of A431 cells, has been investigated by assessing its interactions with glycoproteins and erythrocytes derived from individuals of known blood group ABH, Lewis and secretor types, and by inhibition of binding assays using structurally defined oligosaccharides. The results indicate that this antibody reacts with the difucosylated blood group structures ALeb and ALey: (formula; see text) This antibody differs from the previously described anti-EGF receptor antibody. TL5, which is directed at the terminal blood group A trisaccharide structure and reacts poorly with the ALeb/Ley structures. Since both antibodies were selected for their reactivities with the receptor for EGF, their specificities provide evidence for the presence of both the mono- and difucosylated blood group A structures on the receptor glycoprotein. These antibodies will be invaluable in the studies of the distribution and the roles of blood group related carbohydrate structures in the organisation and function of the EGF and other receptor systems.     

Fungiform papilla pattern: EGF regulates inter-papilla lingual epithelium and decreases papilla number by means of PI3K/Akt, MEK/ERK, and p38 MAPK signaling

Fungiform papillae are epithelial taste organs that form on the tongue, requiring differentiation of papillae and inter-papilla epithelium. We tested roles of epidermal growth factor (EGF) and the receptor EGFR in papilla development. Developmentally, EGF was localized within and between papillae whereas EGFR was progressively restricted to inter-papilla epithelium. In tongue cultures, EGF decreased papillae and increased cell proliferation in inter-papilla epithelium in a concentration-dependent manner, whereas EGFR inhibitor increased and fused papillae. EGF preincubation could over-ride disruption of Shh signaling that ordinarily would effect a doubling of fungiform papillae. With EGF-induced activation of EGFR, we demonstrated phosphorylation in PI3K/Akt, MEK/ERK, and p38 MAPK pathways; with pathway inhibitors (LY294002, U0126, SB203580) the EGF-mediated decrease in papillae was reversed, and synergistic actions were shown. Thus, EGF/EGFR signaling by means of PI3K/Akt, MEK/ERK, and p38 MAPK contributes to epithelial cell proliferation between papillae; this biases against papilla differentiation and reduces numbers of papillae.     

临产前后胎盘组织bcl-2、Fasl的表达与母血、羊水EGF变化的关系

目的探讨临产前后bc l-2、Fasl在胎盘滋养层细胞的蛋白表达变化及其与母血、羊水中表皮生长因子(EGF)的浓度之间的关系。方法53例足月妊娠妇女分成两组,其中临产组28例,未临产组25例。用免疫组化法测定胎盘滋养层细胞bc l-2、Fasl的蛋白表达,用放射免疫法测定孕妇母血、羊水中EGF的浓度。结果(1)临产组bc l-2、Fasl的表达明显低于未临产组(P<0.05)。(2)临产组母血、羊水EGF水平高于未临产组(P<0.05)。(3)母血、羊水中EGF的变化与bc l-2的表达呈负相关,而与Fasl的表达不相关。结论bc l-2、Fasl介导的胎盘滋养层细胞凋亡在启动分娩发动过程中具有重要作用;EGF可能对bc l-2的表达存在下调作用。     

EGF和bFGF对脐血单个核细胞τ蛋白及微管相关蛋白-2 mRNA表达的影响

目的：探讨脐血单个核细胞在细胞因子诱导作用下τ蛋白及微管相关蛋白-2(MAP2) mRNA的表达。方法：用密度梯度离心法分离脐血单个核细胞，接种于含20%胎牛血清H-DMEM培养瓶内。以不加任何生长因子的培养为对照组，其余3组分别加入细胞因子EGF+bFGF、bFGF、EGF,终浓度均为20 μg/L。倒置显微镜下观察细胞形态变化，RT-PCR方法检测脐血单个核细胞培养前后τ蛋白及MAP2 mRNA，免疫细胞化学方法检测τ蛋白及MAP2阳性细胞。结果：培养前，脐血单个核细胞胞体小呈圆形；培养后EGF+bFGF组细胞胞体较大，突起粗而长，EGF组细胞胞体呈梭形，有1-2个长突触，bFGF组细胞胞体较小、有多个细长突起，形似星形细胞，对照组细胞形态类似于bFGF组，但数量较少。RT-PCR检测未培养脐血单个核细胞MAP2 mRNA表达阳性而τ蛋白mRNA呈阴性，培养后MAP2 mRNA表达增强，τ蛋白mRNA亦呈阳性；免疫细胞化学方法可检测MAP2及τ蛋白阳性细胞在EGF+bFGF组、EGF组、bFGF组、对照组分别为33.5%、25.6%、19.6%、14.4%和29.8%、21.4%、15.3%、13.5%。结论：脐血单个核细胞中存在的神经元特异性分子，经培养和生长因子调控后表达增强，联合使用bFGF、EGF具有协同作用。     

Mucin biosynthesis: epidermal growth factor downregulates core 2 enzymes in a human airway adenocarcinoma cell line

Enzymes which exhibit core 2 beta1,6 N-acetylglucosaminyltransferase (C2GnT) activity play important roles in physiologic processes including the inflammatory response and immune system function, and C2GnT activity is regulated during processes, such as T cell activation and cellular differentiation. In this study, we have examined the regulation of C2GnT activity in the H292 airway epithelial cell line by epidermal growth factor (EGF), which has been previously shown to upregulate expression of the airway mucin MUC5AC in this cell line. We found that EGF suppressed C2GnT activity in a time- and dose-dependent fashion, and also suppressed core 4 beta1,6 N-acetylglucosaminyltransferase (C4GnT) activity. Consistent with the suppression of C4GnT activity, Northern blotting results showed that EGF preferentially inhibited the M isoform of C2GnT, which forms core 2, core 4, and blood group I beta1,6 branched carbohydrate structures, while the L isoform, which forms only the core 2 structure, was only modestly affected. Furthermore, EGF treatment resulted in a shift in the carbohydrate structure of FLAG-tagged MUC1 expressed in the cells from core 2-based toward core 1-based structures, consistent with the inhibitory effects of EGF on C2GnT. Transforming growth factor alpha mimicked the effect of EGF on C2GnT, implicating the EGF receptor (EGF-R) in C2GnT suppression, and the EGF-R tyrosine kinase inhibitor AG1478 blocked C2GnT suppression, confirming the role of EGF-R in the inhibition of C2GnT expression. Also, PD98059, a specific inhibitor of mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK)1/2 in the Ras-mitogen-activated protein kinase pathway, completely blocked the EGF suppressive effect, suggesting possible involvement of the Ras-mitogen-activated protein kinase pathway in EGF-mediated downregulation of C2GnT. The results of this study suggest that exposure of airway cells to EGF may result in remodeling of mucin carbohydrate structure, potentially altering the biological properties of the cells.     

EdCC通过MEK-ERK信号通路减轻小鼠心肌缺血再灌注损伤

 目的: 研究子宫内膜干细胞(endometrial stem cells,EnSCs)来源细胞因子“鸡尾酒”(EnSC-derived cytokine cocktail,EdCC)对心肌缺血再灌注损伤的影响及MEK-ERK信号通路的作用。方法: 建立小鼠心肌缺血再灌注损伤模型,用TTC/Evans blue染色评估心梗面积,TUNEL染色检测细胞凋亡,Western blot检测ERK1/2磷酸化水平和cleaved caspase-3表达。结果: EnSCs具有间充质干细胞特性,表达CD90,不表达CD34和CD45。EdCC的表皮生长因子(EGF)含量为(6 811±312)ng/g蛋白。经尾静脉注射EdCC可显著升高心肌ERK1/2磷酸化水平,明显降低梗死面积,减少梗死周边区凋亡细胞数目,抑制capase-3活化。MEK1特异性阻断剂PD98059(5 mg/kg)抑制EdCC介导的ERK1/2磷酸化,并抵消上述心肌保护效应。EGF受体特异性阻断剂AG-1487(6 mg/kg)只能部分抵消EdCC的心肌保护作用,而单纯注射EGF不能缩小梗死面积。结论: EdCC通过激活MEK1-ERK1/2信号通路减轻心肌缺血再灌注损伤,EGF受体是该通路重要组成部分。该结果对目前成体干细胞移植治疗模式——从细胞转移到细胞因子,具有重要的理论意义。     

HGF-induced DNA synthesis in hepatocytes is suppressed by p38

Previous studies in rat hepatocytes have shown that the MEK/ERK, PI3K/Akt and p38 pathways are all involved in the activation of DNA synthesis by EGF and that sustained activation of MEK/ERK is required. Here, we show that although HGF stimulated DNA synthesis and activated signaling in the same manner as EGF, the contribution of the signaling pathways to the induction of DNA synthesis differed. While HGF-induced DNA synthesis was dependent on MEK/ERK, with no significant contribution from PI3K/Akt, p38 suppressed HGF-induced DNA synthesis. The p38 inhibitor SB203580 increased HGF-induced DNA synthesis and enhanced the phosphorylation of ERK. In contrast, SB203580 decreased EGF-induced ERK phosphorylation. This suggests that p38 has distinct effects on DNA synthesis induced by EGF and HGF. Due to differential regulation of signaling through the MEK/ERK pathway, p38 acts as an enhancer of EGF-induced DNA synthesis and as a suppressor of HGF-induced DNA synthesis.     

Activation of the MEK5/ERK5 cascade is responsible for biliary dysgenesis in a rat model of Caroli's disease

Polycystic kidney (PCK) rats exhibit a multiorgan cyst pathology similar to human autosomal recessive polycystic kidney disease, and are proposed as an animal model of Caroli's disease with congenital hepatic fibrosis (CHF). This study investigated the expression and function of selected components of the mitogen activated protein kinase (MAPK) pathway in cultured intrahepatic biliary epithelial cells (BECs) of PCK rats. Compared to the proliferative activity of cultured BECs of control rats, those of the PCK rats were hyperresponsive to epidermal growth factor (EGF). The increase in BEC proliferation was accompanied by overexpression of MAPK/extracellular signal-regulated protein kinase (ERK) kinase 5 (MEK5), and subsequent phosphorylation of ERK5 in vitro. The increased proliferative activity was significantly inhibited by the transfection of short interfering RNA against MEK5 mRNA. An EGF receptor tyrosine kinase inhibitor, gefitinib ("Iressa", ZD1839), also significantly inhibited the abnormal growth of cultured BECs of PCK rats. By contrast, treatment with PD98059 and U0126, inhibitors for MEK1/2, was less effective. These results suggest that the activation of the MEK5-ERK5 cascade plays a pivotal role in the biliary dysgenesis of PCK rats, and also provide insights into the pathogenesis of Caroli's disease with CHF. As the MEK5-ERK5 interaction is highly specific, it may represent a potential target of therapy.