核酸锁修饰的NF-κB诱捕寡核甘酸对肺泡巨噬细胞源性基质金属蛋白酶9表达的影响

目的：研究核酸锁（LNA）修饰的NF-κB诱捕寡核甘酸(ODNs)对TNF-α诱导的慢性阻塞性肺疾病(COPD)患者肺泡巨噬细胞（AM）源性MMP-9、MMP-2表达以及NF-κB活性的影响。方法:从COPD患者支气管肺泡灌洗液中分离与培养AM，脂质体转染NF-κB 诱捕 (decoy) ODNs和NF-κB 错配ODNs，接着以TNF-α刺激AM。以半定量逆转录-聚合酶链反应（RT-PCR）法检测MMP-9、MMP-2 mRNA的表达；以Western blotting检测MMP-9蛋白的表达；以凝胶阻滞分析实验（EMSA）检测NF-κB活性。结果:NF-κB decoy ODNs显著抑制TNF-α诱导的AM源性MMP-9、MMP-2 mRNA及MMP-9蛋白的表达（P<0.05）；错配ODNs则对TNF-α诱导的AM源性MMP-9、MMP-2 mRNA以及MMP-9蛋白的表达无显著影响（P>0.05）。NF-κB decoy ODNs显著降低TNF-α刺激所致的NF-κB活性水平（P<0.05），而错配ODNs则对TNF-α刺激所致的NF-κB活性水平无显著影响（P>0.05）。结论:LNA修饰的NF-κB decoy ODNs能够抑制TNF-α诱导的AM源性MMP-9和MMP-2的表达；LNA修饰和decoy ODNs为COPD的治疗提供了新的思路。     

NF-κB“decoy”寡核苷酸对LPS诱导巨噬细胞IL-10表达的影响

目的：探讨NF-κB “decoy”寡核苷酸（ODNs）对脂多糖（LPS）诱导小鼠巨噬细胞株J774.1表达IL-10的影响。方法： 通过体外细胞培养技术，观察转染NF-κB“decoy”ODNs对LPS刺激巨噬细胞产生IL-10及其表达的影响。结果： 在LPS刺激的巨噬细胞中转染NF-κB“decoy”ODNs对抗炎介质IL-10的合成表达无影响。结论： NF-κB“decoy”ODNs不抑制抗炎介质IL-10的表达，可能由于NF-κB在IL-10转录机制中不占主导地位。     

小窝蛋白1对气道上皮细胞黏液高分泌的影响

目的:探讨小窝蛋白1(Cav-1)对脂多糖(LPS)诱导的气道黏液高分泌的影响。方法:体外培养人气道上皮细胞(16HBE),用LPS刺激细胞构建黏液高分泌模型,以Toll样受体4(TLR4)抑制剂E5564、核转录因子-κB(NF-κB)抑制剂PDTC、转染Cav-1质粒和siRNA为干预因素,将细胞随机分为对照组、LPS刺激组、LPS+Cav-1质粒组、LPS+Cav-1 siRNA组、LPS+阴性siRNA组、LPS+空质粒组、LPS+E5564组及LPS+PDTC组。四甲基偶氮唑盐法(MTT)检测各组细胞的活力;RT-PCR检测黏蛋白(MUC)5AC的转录水平;Western blot检测Cav-1、TLR4、磷酸化IκBα(p-IκBα)蛋白的相对含量;ELISA检测MUC5AC的分泌水平;激光共聚焦技术检测细胞内MUC5AC蛋白的分布和含量。结果:LPS刺激组细胞内TLR4、p-IκBα、NF-κB、MUC5AC转录及蛋白水平显著高于对照组(P值均0.05),过表达Cav-1可进一步增加上述指标的表达量,而下调Cav-1及给予E5564、PDTC可以抑制LPS引起的上述效应(P0.05)。结论:Cav-1可通过上调TLR4/NF-κB信号通路而加重LPS诱导的MUC5AC的表达量。     

Elafin基因重组气道上皮调节脂多糖诱导的人气道黏液高分泌

目的 探讨天然内生多肽Elafin对脂多糖诱导的气道黏液高分泌的调节机制.方法 构建人Elafin重组质粒pEGFP-N1-Elafin,转染正常人支气管上皮细胞HBE16,给予脂多糖(LPS)刺激,激光共聚焦扫描显微镜检测Elafin蛋白含量,Western blot法检测IKBa蛋白含量;荧光素酶报告基因检测系统测定核转录因子-κB(NF-κB)活性;RT-PCR检测Elafin和黏蛋白(MUC)SAC mRNA表达水平;ELISA法分析MUCSAC蛋白相对含量.结果 成功构建内生多肽Elafin真核表达载体pEGFP-N1-Elafin并转染HBEi6细胞.转染重组Elafin后Elafin蛋白含量及mRNA水平明显增加.与对照组相比,LPS刺激组IκBα蛋白含量降低,NF-κB相对活性明显增强,MUC5AC蛋白含量及mRNA水平也显著增加.转染重组Elafin后再予以LPS刺激,与单纯LPS刺激组相比,IκBα蛋白含量明显增加,NF-κB相对活性显著降低,MUCSAC蛋白含量及mRNA水平也明显降低.结论 天然内生多肽Elafin重组气道上皮可下调NF-κB的活性,降低脂多糖诱导的气道黏液高分泌.     

BRAP对LPS诱导的人气道上皮细胞系黏液高分泌的影响

目的探讨蛙皮素受体激活蛋白(BRAP)对脂多糖(LPS)诱导的气道黏液高分泌的影响及相关作用机制。方法体外培养人气道上皮HBE16细胞,转染已构建好的p EGFP-N1-BRAP,以空质粒载体作为对照,给予LPS刺激,同时分别以ERK抑制剂U0126、JNK抑制剂SP600125、P38抑制剂SB203580干预。观察细胞内活性氧(ROS)含量、黏蛋白(MUC)5AC表达和核因子-κB(NF-κB)活性以及细胞活力的变化。结果转染p EGFP-N1-BRAP后ROS明显减少(P0.01);同单纯LPS刺激相比,MUC5AC蛋白含量和mRNA水平在转染p EGFP-N1-BRAP后明显降低(P0.01),NF-κB活性亦呈相同趋势(P0.05);在U0126组,MUC5AC的表达较转染重组质粒组显著降低(P0.01),NF-κB活性也显著下调(P0.05)。结论 BRAP可以通过ROS/ERK/MAPK信号通路阻止胞质内NF-κB的活化,从而下调MUC5AC的生成。     

血红素加氧酶-1抑制香烟烟雾提取物致体外人肺A549细胞黏液高分泌

目的探讨血红素加氧酶-1(HO-1)对香烟烟雾提取物(CSE)所致人气道黏液高分泌的影响。方法用CSE刺激A549细胞,复制黏液高分泌细胞模型。分为对照组、CSE组、氯化高铁血红素(Hemin)组和锌原卟啉(ZnPPIX)组,观察黏蛋白(MUC)5AC、表皮生长因子受体(EGFR)、磷酸化(p)-EGFR、HO-1及双功能氧化酶1(Duox1)的表达。用MTT法测定细胞活性;RT-PCR法检测HO-1、Duox1、EGFR及MUC5AC的mRNA;Western blot法检测p-EGFR、EGFR、Duox1和HO-1蛋白;ELISA法检测细胞裂解液中MUC5AC蛋白表达。结果CSE组MUC5AC的mRNA吸光度积分相对值和蛋白水平分别为0.660±0.044和(157±3)μg/mg,较对照组0.412±0.043和(105±8)μg/mg明显升高(P<0.05),p-EGFR蛋白水平、EGFR、HO-1及Duox1的mRNA和蛋白水平也较对照组明显增高。与CSE组相比,Hemin组HO-1mRNA及蛋白进一步增高,而p-EGFR蛋白水平、Duox1、EGFR及MUC5AC的mRNA和蛋白水平明显回降。与...     

Elafin真核表达载体的构建及其对气道粘液高分泌的调节

目的:构建天然内生多肽Elafin真核表达载体,探讨其对气道粘液高分泌的影响。方法:抽提Elafin行RT-PCR获取Elafin cDNA,双酶切后将片段装载到pMD18-T载体上。以pMD18-T-Elafin为模板行PCR反应,产物胶回收并双酶切后定向克隆至pEGFP-N1上,转化,筛选,双酶切鉴定重组质粒。将pEGFP-N1-Elafin转染正常人支气管上皮细胞HBE16,给予脂多糖(LPS)刺激,Western blot检测细胞内Elafin蛋白的相对含量,RT-PCR检测各组Elafin mRNA和粘蛋白(MUC)5AC mRNA表达水平,荧光素酶报告基因检测系统测定核转录因子-κB(NFκ-B)的活性;ELISA法分析各组细胞MUC5AC蛋白的相对含量。结果:成功构建Elafin真核表达载体,转染重组Elafin的HBE16细胞成功表达Elafin蛋白。LPS刺激可增强NF-κB的活性,该活性在转染重组Elafin后显著降低;MUC5AC蛋白含量及mRNA水平在LPS刺激后也显著升高,在转染重组Elafin后二者的表达水平明显降低。结论:Elafin真核表达载体成功构建,初步发现Elafin可通过降低NFκ-B的活性来下调MUC5AC的表达,为进一步深入研究其对气道粘液高分泌的调节机制奠定了基础。     

TNF-α活化人瘢痕疙瘩成纤维细胞NF-κB的实验研究

目的：观察肿瘤坏死因子－α（TNF-α）对瘢痕疙瘩成纤维细胞（KFB）以及正常皮肤成纤维细胞（NSF）核因子-kappa B（NF-κB）的影响，以探讨瘢痕疙瘩的发生机制。 方法:原代培养成纤维细胞；免疫荧光技术观察NF-κB p65和IκB-α在静息状态和TNF-α刺激后的成纤维细胞中分布；应用TransAMTM NF-κB p65 kit试剂盒检测NF-κB p65 DNA结合活性；应用Western blotting检测IκB-α蛋白水平。 结果: TNF-α刺激后，NF-κB p65从细胞浆转移至细胞核；NF-κB p65 DNA结合活性水平在刺激后1 h达到高峰，4 h接近正常；细胞浆IκB-α蛋白水平在刺激后15 min降至最低值，4 h基本接近正常；KFB较NSF对TNF-α的刺激更为敏感。结论: KFB较NSF对TNF-α活化 NF-κB更为敏感, 可能是瘢痕疙瘩形成的潜在发病机制。     

核转录因子在二氧化硅刺激巨噬细胞产生细胞因子中的作用

目的 探讨二氧化硅(SiO2)刺激巨噬细胞生成肿瘤坏死因子(TNF)-α、转化生长因子(TGF)-β1增多的分子机制及核转录因子Egr-1和NF-κB介导的信号通路在硅肺发生发展中的作用。方法 Egr-1或NF-κB抗体和反义寡核苷酸分别处理巨噬细胞后,用ELISA法检测细胞上清液中TNF-α蛋白的含量;免疫细胞化学链霉素抗生物素蛋白-过氧化物酶(SP)法检测细胞中TGF-β1蛋白的表达;逆转录-聚合酶链反应(RT-PCR)检测TNF-α和TGF-β1mRNA的表达。结果 与非抗体处理组比较,SiO2刺激下抗体处理组巨噬细胞生成TNF-α蛋白和TGF-β1蛋白减少,其mRNA表达也相应下降(P<0.05);与未转染和转染正义寡核苷酸的细胞相比,Egr-1或NF-κB反义寡核苷酸转染细胞后,在SiO2刺激下巨噬细胞生成TNF-α蛋白和TGF-β1蛋白减少,二者mRNA表达也相应下降(P<0.05)。结论 SiO2刺激巨噬细胞生成TNF-α和TGF-β1可能主要是经核转录因子Egr-1和NF-κB介导,Egr-1与NF-κB抗体和反义寡核苷酸的应用可能会导致早期肺泡炎的活动性下降,延缓或阻止肺纤维化的形成。     

MUC1抑制COPD中烟草烟雾诱导的黏液高分泌

目的：探究黏蛋白1(MUC1)对烟草烟雾（CS）暴露诱导的慢性阻塞性肺疾病（COPD）中MUC5AC和MUC5B的表达影响。方法：（1）动物实验：健康SPF级雄性C57BL/6小鼠20只，随机分为空白对照组（n=10）和CS暴露组（n=10），采用CS暴露24周的方法建立COPD小鼠模型。建模结束后，检测小鼠肺功能；肺组织切片进行HE和PAS染色评估肺组织病理改变及气道杯状细胞增生情况；Western blot法检测肺组织MUC1蛋白水平；ELISA法检测支气管肺泡灌洗液中白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)、MUC5AC和MUC5B的表达水平，以评估小鼠肺部炎症及黏液分泌情况。（2）细胞实验：用烟草烟雾提取物（CSE）处理人支气管上皮细胞系16HBE，通过Western blot、RT-qPCR和免疫荧光染色检测MUC1、MUC5AC和MUC5B的表达。用MUC1小干扰RNA(siRNA)和MUC1过表达质粒转染16HBE细胞以沉默和过表达MUC1，确定MUC1对MUC5AC和MUC5B表达的影响。结果：（1）CS组小鼠表现为类似COPD的病变，包括肺气肿、肺功能下...     

JNK信号转导通路介导吸烟所致的气道黏液高分泌

目的：探讨香烟对气道黏液分泌的影响及其信号转导机制。方法: 利用香烟提取物条件培养人气道上皮BEAS-2B细胞，以JNK特异性抑制剂SP600125为干预条件。采用RT-PCR技术观察培养细胞黏蛋白(MUC)5AC转录水平的改变。同时分别采用ELISA和Western blotting法检测培养上清液中MUC5AC和细胞表皮生长因子受体（EGFR）的蛋白水平。结果: 香烟刺激下培养细胞MUC5AC mRNA和蛋白分泌水平显著高于正常培养细胞，同时伴激活态EGFR蛋白含量的显著增高，但EGFR蛋白总量未见显著升高。SP600125显著下调香烟所致MUC5AC表达水平和分泌量的升高水平，而未对激活态EGFR水平的上升产生明显影响。结论: 香烟提取物可从转录水平诱导气道上皮细胞呈现黏液高分泌状态；进一步证明其信号转导机制有EGFR的作用，而JNK信号通路也部分参与其中，且不依赖于EGFR。     

Cigarette smoke synergistically enhances respiratory mucin induction by proinflammatory stimuli

Pathogenic factors associated with chronic obstructive pulmonary disease (COPD), such as cigarette smoke, proinflammatory cytokines, and bacterial infections, can individually induce respiratory mucins in vitro and in vivo. Since co-presence of these factors is common in lungs of patients with COPD, we hypothesized that cigarette smoke can amplify mucin induction by bacterial exoproducts and proinflammatory cytokines, resulting in mucin hyperproduction. We demonstrated that cigarette smoke extract (CSE) synergistically increased gene expression and protein production of MUC5AC mucin induced by LPS or TNF-alpha in human airway epithelial NCI-H292 cells. CSE also enhanced expression and production of MUC5AC mucin induced by epidermal growth factor receptor (EGFR) ligands TGF-alpha and amphiregulin, as well as LPS- and TNF-alpha- induced expression and/or release of TGF-alpha and amphiregulin. Furthermore, (4-[(3-bromophenyl)amino]-6,7-diaminoquinazoline), a potent inhibitor of EGFR, blocked synergistic induction of MUC5AC mucin. H(2)O(2) mimicked the synergistic effects of CSE, while antioxidant N-acetyl-L-cysteine prevented synergistic induction of MUC5AC mucin by CSE. In a rat model of LPS-induced airway inflammation, concurrent cigarette smoke inhalation enhanced mucin content of the bronchoalveolar lavage fluid, muc5AC gene expression, and mucous cell metaplasia in the airways. These results suggest that cigarette smoke has the potential to synergistically amplify induction of respiratory mucins by proinflammatory stimuli relevant to COPD pathogenesis and contribute to mucin hyperproduction observed in patients with COPD.     

c-Ets1 inhibits the interaction of NF-κB and CREB, and downregulates IL-1β-induced MUC5AC overproduction during airway inflammation

Mucin hypersecretion is frequently observed in many inflammatory diseases of the human respiratory tract. As mucin hypersecretion refers to uncontrolled mucin expression and secretion during inflammation, studies examining the negative control mechanisms of mucin hypersecretion are vital in developing novel therapeutic medications. We hypothesized that the c-Ets1 induced by interleukin (IL)-1β would decrease MUC5AC overproduction by inhibiting the interaction of NF-κB with cAMP response element-binding protein (CREB) in vivo. Stimulation with IL-1β caused the direct binding of NF-κB and CREB to the MUC5AC promoter, thus increasing MUC5AC gene expression. However, IL-1β-induced MUC5AC messenger RNA levels were surprizingly downregulated by c-Ets1 (located -938 to -930). Interestingly, c-Ets1 also suppressed IL-1β-induced MUC5AC gene expression in vitro and in vivo by disrupting the interaction of NF-κB with CREB on the MUC5AC promoter. In addition, c-Ets1 also inhibited significant morphologic changes and inflammatory cell infiltration after IL-1β exposure in mouse lungs infected with either wild-type or shRNA-c-Ets1. Moreover, reactive oxygen species produced by NOX4 increased c-Ets1 gene expression and MUC5AC gene expression in alveolar macrophages from bronchoalveolar lavage fluid. These results suggest a molecular paradigm for the establishment of a novel mechanism underlying the negative regulation of mucin overproduction, thus enhancing our understanding of airway inflammation.     

5,7-Dihydroxy-3,4,6-trimethoxyflavone inhibits intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 via the Akt and nuclear factor-κB-dependent pathway, leading to suppression of adhesion of monocytes and eosinophils to bronchial epithelial cells

5,7-Dihydroxy-3',4',6'-trimethoxyflavone (eupatilin), the active pharmacological ingredient from Artemisia asiatica Nakai (Asteraceae), is reported to have a variety of anti-inflammatory properties in intestinal epithelial cells. However, little information is known about the molecular mechanism of eupatilin-induced attenuation of bronchial epithelial inflammation. This study investigates the role of eupatilin in the adhesion of inflammatory cells such as monocytes and eosinophils to bronchial epithelial cells. Stimulation of a human bronchial epithelial cell line (BEAS-2B) with tumour necrosis factor-α (TNF-α) increased the expression of surface adhesion molecules, including intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), in which eupatilin significantly inhibited the expression of those adhesion molecules in a dose-dependent manner. Eupatilin suppressed the TNF-α-induced activation of IκBα and nuclear factor-κB (NF-κB) signals in BEAS-2B cells. The IκB kinase (IKK) activation was also significantly reduced in eupatilin-pre-treated BEAS-2B and primary normal human bronchial epithelial (NHBE) cells. However, eupatilin did not influence AP-1 activity in TNF-α-stimulated cells. Suppression of NF-κB signalling induced by eupatilin resulted in the inhibition of the expression of adhesion molecules and the adhesion of monocytes and eosinophils to BEAS-2B cells. Furthermore, eupatilin suppressed the phosphorylation of Akt in TNF-α-stimulated BEAS-2B and NHBE cells, leading to down-regulation of NF-κB activation and adhesion molecule expression and finally to suppression of the inflammatory cell adhesion to epithelial cells. These results suggest that eupatilin can inhibit the adhesion of inflammatory cells to bronchial epithelial cells via a signalling pathway, including activation of Akt and NF-κB, as well as expression of adhesion molecules.     

抗氧化剂和NF-κB对大肠癌细胞IL-8表达的作用及机制

目的：探讨NF-κB在大肠癌细胞IL-8诱导表达中的作用及抗氧化剂对大肠癌细胞IL-8诱导表达的影响及其机制。 方法： IL-8 mRNA表达采用逆转录/聚合酶链反应(RT/PCR)检测，培养上清IL-8蛋白含量用ELISA检测，EMSA法测定细胞核内NF-κB结合活性。 结果： 抗氧化剂可阻断大肠癌细胞培养体系TNF-α诱导的IL-8生成及IL-8 mRNA的表达, TNF-α可诱导大肠癌细胞NF-κB的激活并被抗氧化剂阻断。 结论： TNF-α诱导的大肠癌细胞IL-8基因和蛋白表达依赖于NF-κB的激活；抗氧化剂可通过抑制NF-κB的活化而阻断IL-8基因和蛋白的诱导表达。     

Isorhamnetin attenuates TNF-α-induced inflammation,proliferation, and migration in human bronchial epithelial cells via MAPK and NF-κB pathways

Isorhamnetin has distinct anti-inflammatory activity and inhibits cell proliferation and migration. These effects are also involved in the pathogenesis of asthma. However, the effect of isorhamnetin on bronchial epithelial cells in patients with asthma has not been examined. Cells of human bronchial epithelial cell line BEAS-2B were cultured with isorhamnetin and tumor necrosis factor (TNF)-α. The effects of isorhamnetin on BEAS-2B cell viability were assessed using CCK8 assay. The EdU (5-ethynyl-2′-deoxyuridine) cell proliferation assay was performed to assess cell proliferation. BEAS-2B cell migration was measured using Transwell and wound healing assays. Real-time PCR and enzyme-linked immunosorbent assay were conducted to measure the expression of pro-inflammatory cytokines. Protein expression levels were determined by western blotting. Immunofluorescence was used to detect nuclear translocation of nuclear factor kappa B (NF-κB). We found that isorhamnetin at 20 and 40 μM reduced the proliferation of BEAS-2B cells induced by TNF-α. Isorhamnetin significantly decreased the expression of interleukin (IL)-1β, IL-6, IL-8, and C-X-C motif chemokine ligand 10 in BEAS-2B cells induced by TNF-α. Additionally, 10 μM isorhamnetin effectively reduced cell migration induced by TNF-α. Treatment with isorhamnetin inhibited the phosphorylation of mitogen-activated protein kinase (MAPK) and NF-κB pathways induced by TNF-α. In summary, isorhamnetin inhibited the inflammation, proliferation, and migration of BEAS-2B cells by regulating the MAPK and NF-κB signaling pathways and is a drug candidate for asthma.     

Mechanisms of mucin production by rhinovirus infection in cultured human airway epithelial cells

Mucus hypersecretion relates to exacerbations of bronchial asthma and chronic obstructive pulmonary disease (COPD) caused by rhinovirus (RV) infection. We examined the mechanisms of RV infection-induced mucin production in human tracheal surface epithelial cells and submucosal gland cells. RV14 up-regulated the mRNA expression of MUC2, MUC3, MUC5AC, MUC5B and MUC6, and increased MUC5AC and total mucin concentration in supernatants and lysates of the surface cells. An inhibitor of the nuclear factor kappaB caffeic acid phenylethyl ester, inhibitors of selective p44/42 mitogen-activated protein kinase-kinase PD98059 and U0126, and a selective Src inhibitor PP1 attenuated MUC5AC mRNA expression, and secretion and production of MUC5AC and total mucin glycoprotein in the surface cells. In the gland cells, RV14 also increased mRNA expression of MUC2, MUC5AC, MUC5B and MUC7, and the inhibitors attenuated the secretion of total mucin glycoprotein. Src-related p44/42 mitogen-activated protein kinase pathway may be associated with RV-induced mucin hypersecretion in human airways.