NF-κB与心脏移植

1 NF～κB概述 核因子-κB（nuclear factor—κB NF-κB）首先是由Sen和Baltimore于1986年报道，NF-κB是一组真核细胞转录因子，由NF—κB／Rel蛋白家族成员NF—κB1（p50，其前体p105），NF-κB2（p52，前体p100），RelA（p65），RelB和C—Rel以同源或异源二聚体形式组成，不同的NF—κB／Rel蛋白双双结合形成不同的NF—κB，以p50／p65发现最早，分布和作用最广泛，是通常所说的NF-κB。通常情况下，大多数细胞中的NF—κB与其抑制因子（IκB）蛋白家族成员（包括bcBα，IκBβ，IβBγ和BcL-3等，其中M3a是最重要的NF-κB活性调控成员）相结合，     

Effects of Triptolide on the Expression and Activity of NF-κB in Synovium of Collagen-induced Arthritis Rats

Summary： The expression and activity of NF-kB in the synovium of collagen-induced arthritis （CIA） rats was detected in order to investigate the possible therapeutic effects of triptolide on rheumatoid arthritis （RA）. The experimental Wistar rat model of CIA was set up by intradermal injection of emulsion of bovine collagen 11 and the successful rate of setting-up models was evaluated by arthritis index （AI）. Rats were grouped randomly into three groups： normal, model and treatment group. The expression of TNF-α and IL-6 in synovial fluid was detected by ELISA, and the expression and activity of NF kB in synovium by immunohistochemistry method and by electrophoretic mobility shift assay （EMSA） respectively. As compared with normal group, the expression of TNF a and IL-6 in synovia （P〈0. 05）, and the expression and activity of NF-kB （P〈0.05） in synovium were increased in model group. There was statistical difference in above-mentioned indexes between model group and treatment group. Triptolide may play a protective role in IRA via downregulating the expression and activity of NF-kB in synovium.     

NF-κB与肿瘤的关系

198 6年 ,Sen和Baltimore在成熟的B细胞核提取物中发现一种与免疫球蛋白κ轻链基因的增强子中特定DNA位点结合的蛋白 ,命名为核转录因子 (Nu clearfactorkappaB ,NF -κB)。NF -κB最初被认为是淋巴细胞特异性的 ,后来发现其广泛存在于各种细胞中 ,并参与细胞内的信号传递 ,调控多种基因的表达。它的异常激活或完全抑制与多种疾病的发生有关。本文拟就NF -κB与肿瘤的关系进展做一综述。1　NF -κB的结构特点目前 ,已鉴别和克隆成功 5种哺乳动物NF -κB家庭成员 ,即NF -κB1(P5 0 /10 5 ) ,NF -κB2 (P5 2 /P10 0 ) ,P6 5 (Re…     

NF-κB信号转导通路与胰岛素抵抗

核因子-κB(NF-κB)信号转导通路包括NF-κB、NF-κB抑制蛋白(IκB)和IκB激酶(IKK).其中,NF-κB是一种重要的核转录因子,参与炎症反应、免疫反应、细胞凋亡及物质代谢等多种生物进程.IKK具有丝氨酸/苏氨酸激酶活性,能使多种蛋白的丝氨酸/苏氨酸残基磷酸化.NF-κB信号转导通路的活化与胰岛素抵抗的发生密切相关.文章就NF-κB在胰岛素抵抗发生中作用作一综述.     

NF-κB信号转导通路与胰岛素抵抗

核因子-κB（NF—κB）信号转导通路包括NF—κB、NF—κB抑制蛋白（IκB）和IκB激酶（IKK）。其中,NF—κB是一种重要的核转录因子,参与炎症反应、免疫反应、细胞凋亡及物质代谢等多种生物进程。IKK具有丝氨酸／苏氨酸激酶活性,能使多种蛋白的丝氨酸／苏氨酸残基磷酸化。NF—κB信号转导通路的活化与胰岛素抵抗的发生密切相关。文章就NF—κB在胰岛素抵抗发生中作用作一综述。     

Activation of NF-κB and its regulation on IL-6 expression during LPS-induced liver injury

Objective： To explore the kinetics of the activation of nuclear factor-kappa B （NF-κB） and its regulation of interleukin-6 （IL-6） expression during LPS induced liver injury. Methods： Kunming mice were randomly divided into 4 groups in order to observe the does effect relationship at 3h： normal saline solution （control） group, low （1 mg/kg）, middle （5 mg/kg）, and high （10 mg/kg） LPS-induced groups; 6 groups in order to observe the time-effect relationship of 5 mg/kg LPS injection： normal saline solution （control） group, 0.5, 1, 3, 5 and 8 h groups ; pyrrolidine dithiocarbamate （PDTC） intervened groups （3 h）： normal saline solution （control） group, 5 mg/kg LPS, 200 mg/kg PDTC, and 200 mg/kg PDTC＋5 mg/kg LPS groups. NF-κB activities of Kupffer cells were determined with electrophoretic mobility shift assay （EMSA） and expression levels of IL-6 were measured with enzyme-linked immunosorbent assay （ELISA）. Results： Does-effect of NF-κB activities in Kupffer cells after LPS injection 3 h： NF-κB activation could be detected in 1 mg/kg LPS group, reached the highest level in 5 mg/kg LPS group, and persisted in 10 mg/kg LPS group; time-course after 5 mg/kg LPS injection： the DNA-binding activity was observable at 0.5 h after LPS injection, increased significantly at 3 h, and persisted for at least 8 h; in addition, antioxidant PDTC could inhibit the activation of NF-κB significantly. The kinetics of IL-6 level in liver tissues during LPS-induced liver injury were that IL-6 level after 3 h of injection increased first and then reduced; the same trend was observed in the time-course on IL-6 level after LPS injection; PDTC could significantly inhibit the release of IL-6. Correlation analyses revealed that IL-6 level was significantly and positively correlated with the activation of NF-κB. Conclusion ： NF-κB in Kupffer cells can be activitied during LPS-induced liver injury to some extent, and NF-κB may have some regulation on the expression of IL-6.     

Change and significance of nuclear factor-κB in adriamycin induced cardiomyopathy in rats

Background This study aimed at investigating the change and significance of nuclear factor-κB (NF-κB) in eardiomyopathy induced by adriamyein (ADR) in rats. Methods Sixty male Wistar rats were randomly divided into three groups: control, ADR and ADR pyrrolidine dithiocarbamate (PDTC) groups. After 30-day experiment, myocardial histopathological observation was performed. Location and distribution of NF-κB p50 was examined by immunohistochemical assay. Expression of NF-κB p50 protein was examined by immunoboh assay. Electrophoretic Mobility Shift Assay examined activity of NF-κB; Myocardium p53 gene expression was examined by RT-PCR analysis. Results The myocardial lesions of rats were less pronounced in ADR PDTC group than in ADR group. Compared with control group, there were many myocardium nucleuses, which expressed NF-κB p50 and distribute under epicardium. Expression of NF-κB p50 protein in nucleus increased significantly in ADR group. The NF-κB binding activity increased significantly in ADR group. Myocardium expressions of p53 mRNA increased in ADR group. Conclusions The NF-κB binding activity increased significantly in cardiomyopathy induced by ADR in rats. Moreover, NF-κB plays an important role in causing degeneration of myocardial tissue and regulating expression of related-apoptosis genes.     

NF-κB与角膜新生血管的研究进展

核因子NF-κB(nuclear factorκB,NF-κB)是一种广泛存在于体内多种细胞的核转录因子,目前已发现它调节着100 多种靶基因的表达,如细胞因子、化学趋化因子、生长因子、黏附分子等.目前,随着人们对NF-κB的研究日益重视并逐渐深入,它与眼科疾病的密切关系也进一步被证实,NF-κB的活化在角膜新生血管发生发展中发挥的重要作用也日益受到人们的重视.     

Relationship between Carbachol Hyperstimulation-induced Pancreatic Intracelluar Trypsinogen and NF-κB Activation in Rats in vitro

The relationship between intracelluar trypsinogen activation and NF-κB activation in rat pancreatic acinar cells induced by M3 cholinergic receptor agonist （carbachol） hyperstimulation was studied. Rat pancreatic acinar cells were isolated, cultured and treated with carbachol, the active protease inhibitor （pefabloc） and NF-κB inhibitor （PDTC） in vitro. Intracelluar trypsin activity was measured by using a fluorogenic substrate. The activity of NF-κB was monitored by using electrophoretic mobility shift assay. The results showed that after pretreatment with 2 mmol/L pefabloc, the activities of trypsin and NF-κB in pancreatic acinar cells treated with high concertrations of carbachol （10^-3 mol/L） in vitro was significantly decreased as compared with control group （P〈0.01 ）. The addition of 10^-2 mol/L PDTC resulted in a significant decrease of NF-κB activities in pancreatic acinar cells after treated with high concertrations of carbachol （10^-3 mol/L） in vitro, but the intracelluar trypsinogen activity was not obviously inhibited （P〉0.05）. It was concluded that intracelluar trypsinogen activation is likely involved in the regulation of high concertrations of carbachol-induced NF-κB activation in pancreatic acinar cells in vitro. NF-κB activation is likely not necessary for high concertrations of carbachol-induced trypsinogen activation in pancreatic acinar cells in vitro.     

NF-κB与神经系统疾病的关系

核转录因子NF-κB对感染、免疫反应以及控制细胞分化和凋亡起到广泛的效应,这些效应较为明显存于在神经系统中。NF-κB通常以多种亚单位形式存在于各种神经细胞中,通过多个激活途径被激活后从胞浆移位至细胞核内发挥转录激活作用,NF-κB在对神经系统发育和抗凋亡中以及调节胶质细胞活性过程中起到十分重要的作用。本文主要对NF-κB的生物学特性、抗肿瘤机制及神经系统疾病的关系做一综述。     

The expression and significance of NF-κB in endothelial cells of deep venous thrombosis

目的 探讨核因子-κB(NF-κB)在孕鼠深静脉血栓形成(DVT)后其血管内皮细胞中的动态变化及意义.方法 清洁级SD孕鼠54只,其中48只采用下腔静脉结扎法建立深静脉血栓模型后,随机分为血栓模型组、吡咯烷二硫代氨基甲酸盐(PDTC)干预组,分别于术后6、12、24、72 h处死;余6只为假手术组.比较血栓模型组和PDTC干预组静脉血栓的形成情况并观察其病理学形态,采用免疫组化SP法检测各组血管内皮细胞中NF-κB的表达水平.结果 NF-κB蛋白水平于静脉血栓形成后6 h开始升高,24 h达高峰,72 h后下降.与假手术组比较,血栓模型组和PDTC干预组各时间点静脉血管内皮细胞中NF-κB的表达均显著增强(P＜0.05).NF-κB抑制剂PDTC干预后静脉血管内皮细胞中NF-κB的表达显著下降,72 h后血栓重量与长度比值显著低于血栓模型组(P＜0.05).结论 孕鼠DVT血管内皮细胞中NF-κB明显激活,并介导血管内皮的损伤,抑制NF-κB的信号通路可能对DVT有潜在的治疗价值.     

Inhibition of NF-κB by mutant IκBα enhances TNF-α-induced apoptosis in HL-60 cells by controlling bcl-xL expression

Backgound The aim of this study was to explore whether the inhibition of nuclear factor-κB (NF-κB)activation by mutant IκBα (S32,36→A) can enhance TNF-α-induced apoptosis of leukemia cells and to investigate the possible mechanism. Methods The mutant IκBα gene was transfected into HL-60 cells by liposome-mediated techniques. G418 resistant clones stably expressing mutant IκBα were obtained by the limiting dilution method. TNF-α-induced NF-κB activation was measured by electrophoretic mobility shift assay (EMSA). The expression of bcl-xL was detected by RT-PCR and Western blot after 4 hours exposure of parental HL-60 and transfected HL-60 cells to a variety of concentrations of TNF-α. The percentage of apoptotic leukemia cells was evaluated by flow cytometry (FCM). Results Mutant IκBα protein was confirmed to exist by Western blot. The results of EMSA showed that NF-κB activation by TNF-α in HL-60 cells was induced in a dose-dependent manner, but was almost completely inhibited by mutant IκBα repressor in transfected cells. The levels of bcl-xL mRNA and protein in HL-60 cells increased after exposure to TNF-α, but changed very little in transfected HL-60 cells. The inhibition of NF-κB activation by mutant IκBα enhanced TNF-α-induced apoptosis. Thecytotoxic effects of TNF-α were amplified in a time- and dose-dependent manner. Conclusions NF-κB activation plays an important role in the resistance to TNF-α-induced apoptosis. The inhibition of NF-κB by mutant IκBα could provide a new approach that may enhance the antileukemia effects of TNF-α or even of other cytotoxic agents.     

金雀黄素抑制人肝癌细胞Bel 7402中 NF-κB表达的实验研究

从核转录因子水平探讨金雀黄素抗肿瘤作用机理.采用MTT法测定金雀黄素抑制肿瘤的作用;通过免疫组化、Western Blot及电泳迁移率变动分析,分别检测了用药前后p65和I κ Bα在人肝癌细胞株Bel 7402中的表达.结果提示金雀黄素有显著抑制肿瘤生长的作用,用药后,Bel 7402细胞中的p65表达水平降低,而IκBα表达较用药前高.表明金雀黄素的抗肿瘤作用机理与其抑制IκBα降解从而抑制NF-κB功能有关.     

NF-κB与癌症发生的关系研究进展

核转录因子κB（NF-κB）是参与一系列基因表达调控的关键性核转录因子，其在癌症的起源、发展、血管新生及转移中具有重要作用，并与癌症耐药性的产生密切相关，从而引起许多不同领域研究者们的广泛关注。本文对NF-κB与癌症发生的关系的最新研究进展以及对癌症治疗的启示作一综述。     

NF-κB抑制剂PDTC增敏TNF-α对乳腺癌细胞的毒性作用

目的 :探讨核因子κB(nuclearfactorkappaB)活化抑制剂二硫代氨基甲酸吡咯烷 (pyrro1idinedithiocarbamate,PDTC)对肿瘤坏死因子α(tumornecrosisfactorα,TNF -α)细胞毒性作用的影响。方法 :用MTT法观察TNF -α、PDTC及二者联合作用对乳腺癌细胞系MCF - 7、MDA -MB - 4 35s体外生长的影响。将MDA -MB - 4 35s细胞接种于雌性BALB/c纯系小鼠肾包膜下复制出移植乳腺癌动物模型 ,观察TNF -α、PDTC及联合作用对体内移植肿瘤生长的影响。结果 :单用TNF -α(小于或等于 2 0 0 0U/ml)或PDTC均不影响两种乳腺癌细胞的体外生长 ,但是先PDTC(5 0 μmol)作用 1h ,再应用TNF -α(2 0 0 0U/ml)即可明显地抑制乳腺癌细胞的生长。动物实验中治疗组应用TNF -α(7.5× 10 6U/kg/次 ,2次 /日 ,ip) +PDTC(5 0mg/kg/次 ,2次 /日 ,ip) ,肿瘤平均体积为 1.0 8± 0 .32mm3 ,明显小于对照组平均瘤体 11.6 7± 0 .5 3mm3 (P <0 .0 1) ,单用TNF -α组(10 .96± 1.0 4mm3 )及PDTC组 (11.72± 0 .73mm3 )与对照组比较无显著差异 (P >0 .0 5 )。结论 :NP -κB抑制剂PDTC能够显著增敏TNF -α对乳腺癌细胞的毒性作用 ,抑制乳腺癌细胞的生长。     

Pro-apoptotic role of NF-κB pathway inhibition in lipopolysaccharide stimulated polymorphonuclear neutrophils

Objective To investigate the role of nuclear factor kappa B (NF-κB) pathway inhibition in lipopolysaccharide (LPS)-stimulated apoptosis of polymorphonuclear neutrophils (PMNs).Methods Rats with acute lung injury induced by LPS intratracheal instillation and cultured human venous PMNs were studied. Pyrrolidine dithiocarbamate (PDTC) and gliotoxin were used as NF-κB inhibitors. Additionally, to explore the role of extracellularly regulated protein kinase as an upstream signal in NF-κB pathway on regulating LPS-stimulated PMN apoptosis, PD098059, the specific inhibitor of extracellularly regulated protein kinase, was also applied. The lung injury was determined by protein content and PMN numbers in bronchoalveolar lavage fluid. PMN apoptosis was measured by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP) end labeling and DNA fragmentation. IκBα degradation was analyzed by Western blot. NF-κB DNA binding activity was detected by an electrophoretic mobility shift assay.Results (1) The increase of protein content and PMN numbers in bronchoalveolar lavage fluid induced by LPS (100μg per rat) intratracheal instillation were alleviated by PDTC (50, 100, or 200mg/kg, i. p. ) in a dose-dependent manner. (2) PMNs apoptosis in vivo or in vitro was delayed by LPS, and accelerated by PDTC, gliotoxin or PD098059 pretreatment. (3) IκBα degradation and increased NF-KB DNA binding activity mediated by LPS were inhibited by PDTC, gliotoxin or PD098059 pretreatment.Conclusion Inhibition of either NF-κB itself or the upstream signals in NF-κB pathway such as extracellularly regulated protein kinases has therapeutic effect on LPS-induced acute lung injury, in which the dysregulation of PMN apoptosis plays an important role.