Adenovirus-mediated overexpression of novel mutated IκBα inhibits nuclear factor κB activation in endothelial cells

Nuclear factor κB （NF-κB） overactivation, requiring phosphorylation and degradation of its inhibitor IκBα, is the basis for chronicity of airway inflammation in asthma. Based on our previous plasmid pShuttle-IκBα, carrying an IκBα gene from human placenta, we optimized a novel IκBα mutant （IκBα） gene, constructed and characterized its replication-deficient recombinant adenovirus （AdIκBαM）, and tested whether AdIκBαM-mediated overexpression of IκBαM could inhibit the NF-κB activation in endothelial cells.     

Aspirin inhibits tumor necrosis factor-α-stimulated fractalkine expression in human umbilical vein endothelial cells

Background Fractalkine is an important chemokine mediating local monocyte accumulation and inflammatory reactions in the vascular wall. Aspirin inhibits inflammatory cytokine expression closely related to atherosclerosis through the way independent of platelet and cyclooxygenase （COX）. There has been no report about the effect of aspirin on fractalkine expression. We aimed to determine the fractalkine expression in human umbilical vein endothelial cell （HUVEC） stimulated by tumor necrosis factor （TNF）-α and the effect of aspirin intervention.
Methods Six of 8 HUVEC groups received either different concentrations of aspirin （0.02, 0.2, 1.0, 5.0 mmol/L） or 40 μmol/L pyrrolidinecarbodithioc acid （PDTC） or 0.5 μmol/L NS-398. The other two groups were negative control and positive control （TNF-α-stimulated）. After being incubated for 24 hours, cells of the 8 groups except the negative control one were stimulated with TNF-α （4 ng/ml） for another 24 hours. After that, the cells were collected for RNA isolation and protein extraction.
Results Both mRNA and protein expressions of fractalkine in HUVEC were upregulated by 4 ng/ml TNF-α stimulation. Aspirin inhibited fractalkine expression in a dose-dependent manner at mRNA and protein levels. Nuclear factor-kappa B inhibitor, PDTC, effectively decreased the fractalkine expression. Fractalkine expression was not influenced by COX-2 selective inhibitor NS-398. COX-1 protein expression was not changed by either TNF-α stimulation or aspirin, PDTC, NS-398 intervention. Both mRNA and protein expression of COX-2 in HUVEC were upregulated by 4 ng/ml TNF-α stimulation. Aspirin decreased COX-2 expression in a dose-dependent manner at mRNA and protein levels.
Conclusions TNF-α-stimulated fractalkine expression is suppressed by aspirin in a dose-dependent manner through the nuclear factor-kappa B p65 pathway.     

Molecular mechanism of endothelial cells about adhesion and proliferation in tissue engineering heart valve of seeding human umbilical vein endothelial cells on decellular porcine aortic valve

Objective To create the tissue engineering heart valve （TEHV） by seeding human umbilical vein endothelial cells （HUVECs） on decellular porcine aortic valve and investgate its mechanism of endothelial cells in adhesion and proliferation.Methods The porcine aortic valve was acellularized by using trypsin、EDTA、Triton X-100、RNase and DNase treatment.Biomechanical characteristics of fresh valves and acellularized valves were tested.     

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.     

Metformin inhibits nuclear factor-κB activation and inflammatory cytokines expression induced by high glucose via adenosine monophosphate-activated protein kinase activation in rat glomerular mesangial cells in vitro

Background The renoprotective mechanisms of adenosine monophosphate （AMP）-activated protein kinase （AMPK） agonist-metformin have not been stated clearly.We hypothesized that metformin may ameliorate inflammation via AMPK interaction with critical inflammatory cytokines The aim of this study was to observe the effects of metformin on expression of nuclear factor-κB （NF-κB）,monocyte chemoattractant protein-1 （MCP-1）,intercellular adhesion molecule-1 （ICAM-1） and transforming growth factor-beta 1 （TGF-β1） induced by high glucose （HG） in cultured rat glomerular mesangial cells （MCs）.Methods MCs were cultured in the medium with normal concentration glucose （group NG,5.6 mmol/L）,high concentration glucose （group HG,25 mmol/L） and different concentrations of metformin （group M1,M2,M3）.After 48-hour exposure,the supernatants and MCs were collected.The expression of NF-κB,MCP-1,ICAM-1,and TGF-β1 mRNA was analyzed by real time polymerase chain reaction.Westem blotting was used to detect the expression of AMPK,phospho-Thr-172 AMPK （p-AMPK）,NF-κB p65,MCP-1,ICAM-1,and TGF-β1 protein.Results After stimulated by HG,the expression of NF-κB,MCP-1,ICAM-1,TGF-β1 mRNA and protein of MCs in group HG increased significantly compared with group NG （P ＜0.05）.Both genes and protein expression of NF-κB,MCP-1,ICAM-1,TGF-β1 of MCs induced by high glucose were markedly reduced after metformin treatment in a dose-dependent manner （P ＜0.05）.The expression of p-AMPK increased with the rising of metformin concentration,presenting the opposite trend,while the level of total-AMPK protein was unchanged with exposure to HG or metformin.Conlusion Metformin can suppress the expression of NF-κB,MCP-1,ICAM-1 and TGF-β1 of glomerular MCs induced by high glucose via AMPK activation,which may partlv contribute to its reno-protection.     

Interleukin-13 inhibits cytokines synthesis by blocking nuclear factor-κB and c-Jun N-terminal kinase in human mesangial cells

Objective： Monocytes/macrophages, proinflammatory cytokines and chemokines are important in the pathogenesis of glomerulonephritis. Interleukin （IL） -13 has been shown to exert potent anti-inflammatory properties. This study was designed to investigate the effect of IL-13 on the expression of proinflammatory cytokines, chemokines and profibrogenic cytokines and the involved molecular mechanism in cultured human mesangial cells （HMCs）. Methods： The expressions of proinflammatory cytokines, chemokines and profibrogenic cytokines were determined by ribonuclease protection assay （RPA）. Activity of nuclear factor-kappa B （NF-κB） and activa- tor protein-1 （AP-1） was examined by electrophoretic mobility shift assay （EMSA）. NF-κB subunit p65 nuclear transportation and c-Jun N-terminal kinase （JNK） activity were assayed by immunoblot. Results： Recombinant IL-13 inhibited tumor necrosis factor-α （TNF-u）, IL-1α, IL-1β, monocyte chemoattractant protein-1 （MCP-1）, IL-8, and transforming growth factor-β1 （TGF-β1） mRNA expressions in a dose-dependent manner. Lipopoly- sacchorides （LPS） dramatically increased NF-κB DNA binding activity of HMCs, which was inhibited by IL-13 in a dose-dependent manner. LPS-activated NF-κB contained p50 and p65 dimers, but not c-Rel subunit. IL-13 blocked LPS-induced NF-κB subunit p65. LPS stimulated JNK/AP-1 activation, which was inhibited by IL-13 in a dose-dependent manner. Conclusion： IL-13 inhibits proinflammatory cytokines, chemokines, and profibrogenic cytokines synthesis by blocking NF-κB and JNK/AP-1 activation. These observations point to the importance of IL-13 in the modulation of inflammatory processes in the renal glomerulus.     

Effect of immunoglobulin G from patients with Graves’ ophthalmopathy and in terferon gamma in intercellular adhesion molecule-1 and human leucocyte antigen-DR expression in human retroocular fibroblasts

Objective To detect the expression of intercellular adhesion molecule-1 (ICAM-1) and human leucocyte antigen-DR (HLA-DR) on retroocular fibroblasts (RFs) by immunoglobulin G (IgG) from patients with Graves’ ophthalmopathy (GO) and interferon gamma (IFN-γ) and to study the possible mechanism of humoral immunity and cellular immunity in the pathogenesis of GO. Methods Purified IgG was obtained from 23 patients (GO 10, Graves’ disease 9, toxic multinodular goiter 4) and 8 normal persons. Cytokine IFN-γ and thyroid stimulating hormon (TSH) were incubated with normal human RF cultured in vitro. Antigen expression on RFs induced by stimulators was examined using immunofluoresence staining and a flow cytometer. Results RFs spontaneously expressed ICAM-1, but did not express HLA-DR. All IgGs from patients with GO and other thyroid diseases as well as from normal persons could not stimulate the expression of ICAM-1 on RFs. IFN-γ and TSH significantly enhanced the expression of ICAM-1 in dose-dependent manner (P<0.05). Only IFN-γ could stimulate RFs to express HLA-DR (P<0.05). Conclusions IgG from patients with GO did not stimulate the expression of ICAM-1 and HLA-DR on the surface of cultured normal human RFs. IFN-γ was the important factor for initiating and promoting autoimmune reactions in GO. We need to pay more attention to TSH, as it may possibly play a promoting role in the pathogenesis in GO.     

Reduction of atherosclerosis in cholesterol-fed rabbits and decrease of expressions of intracellular adhesion molecule-1 and vascular endothelial growth factor in foam cells by a water-soluble fraction of Polygonum multiflorum

Polygonum multiflorum stilbeneglycoside （PMS） is a water-soluble fraction of Polygonum multiflorum Thunb. , one of the most famous tonic traditional Chinese medicines, that has protective effects on the cardiovascular system. The purpose of the present study is to elucidate the effects of PMS on macrophage-derived foam cell functions and the reduction of severity of atherosclerosis in hypercholesterolemic New Zealand White （NZW） rabbits. NZW rabbits were fed for 12 weeks with a normal diet, a high cholesterol diet, or a high cholesterol diet associated with irrigation with different doses of PMS （25, 50, or 100 mg/kg）. Treatment of NZW rabbits fed with high cholesterol diet with 100 mg/kg PMS attenuated the increase in plasma cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and plasma triglyceride. Treatment with 50 and 100 mg/kg PMS caused 43% and 60% decrease in atherosclerotic lesioned area ratio to total surface area, respectively. In U937 foam cells, PMS could decrease the high expression of intercellular adhesion molecule （ICAM）-1 protein and the vascular endothelial growth factor （VEGF） protein levels in the medium induced by oxidized lipoprotein when analyzed by flow cytometry. The results proved that PMS is a powerful agent against atherosclerosis and that PMS action could possibly be through the inhibition of the expression of ICAM-1 and VEGF in foam cells.     

Inhibition of nuclear factor-κB activity enhanced chemosensitivity to cisplatin in human lung adeno-carcinoma A549 cells under chemical hypoxia conditions

Background Tumor hypoxia,one of the features of solid tumors,is associated with chemo-resistance.Recently,nuclear factor-KB (NF-kB) was found to be activated during hypoxia.However,the impact of NF-kB ...     

Effects of Fucoidan on the expression of MMP2 and TIMP-2 in human mesangial cells cultured with growth factor β1

目的 观察褐藻多糖硫酸酯(Fucoidan FPS)对TGF-β1下刺激人肾小球系膜细胞MMP-2、TIMP-2分泌的影响,探讨其在慢性肾衰竭(Chronic Renal Failure CRF)防治中的意义.方法 用TGF-β1作为刺激因子,孵育体外培养的人肾小球系膜细胞(Human Mesangial cell HMC),并分别用不同浓度的FPS干预,具体分组如下:模型组(TGF-β14 ng/ml)、FPS高剂量组(TGF-β14 ng/ml +FPS 100 ug/ml)、FPS中剂量组(TGF-β14 ng/ml + FPS 50 ug/ml)、FPS低剂量组(TGF-β14 ng/ml + FPS 25 ug/ml)、FPS对照组(FPS 100ug/ml)、正常对照组.ELISA技术检测HMC培养上清液中MMP-2、TIMP-2蛋白表达水平,Realtime PCR技术检测HMC 的MMP-2、TIMP-2 mRNA表达水平.结果 与正常对照组相比,TGF-β1能减少HMC的MMP-2蛋白及mRNA表达 (P＜0.01),增加HMC的TIMP-2蛋白及mRNA表达 (P＜0.01);FPS能阻断TGF-β1刺激下HMC的MMP-2蛋白及mRNA表达减少、TIMP-2蛋白及mRNA表达增加(P＜0.01,P＜0.05);FPS对照组与正常对照相比MMP-2、TIMP-2蛋白及mRNA表达差异无统计学意义(P＞0.05).结论 褐藻多糖硫酸酯能阻断TGF-β1刺激下人肾小球系膜细胞MMP-2、TIMP-2表达的比例失衡,阻断了由MMP-2、TIMP-2比例失衡导致的ECM积聚,从而延缓了慢性肾衰竭的进展.     

Correlations of hypoxia-inducible factor-1α/hypoxia-inducible factor -2α expression with angiogenesis factors expression and prognosis in non-small cell lung cancer

Background  Hypoxia-inducible factor (HIF) may play an important role in the process of tumorigenesis as well as tumor progression. The aim of this study was to compare the expression between HIF-1α and HIF-2α in tumor angiogenesis and the overall impact on patient prognosis in human non-small cell lung cancer (NSCLC).

Methods  In the current work we compared the immunohistochemical expression of HIF-1α and HIF-2α in surgical specimens of 140 patients with NSCLC in a tissue microarray study. Relationships between HIF-α expression and clinicopathological or angiogenic factors, including prognosis, were analyzed.

Results  High HIF-1α and HIF-2α expression was noted in 49/140 (35.0%) and in 64/140 (45.7%) of the cases, respectively. There was no direct correlation between HIF-1α and HIF-2α expression. Patients with advanced stage tumors had frequent high expression of HIF-2α (P=0.007), and we also found a significant correlation between HIF-2α and T or N stage (P=0.030 and 0.043, respectively). HIF-1α showed a marginal association with T stage (P=0.084), which showed a higher expression in early stage tumors. A significant correlation (P=0.045) was noticed between HIF-1α and vascular endothelial growth factor (VEGF) expression while the expression levels of thymidine phosphorylase (TP), cyclooxygenase (COX)-2 and microvessel density (MVD) were significantly higher in high HIF-2α tumors (P=0.020, 0.004, and 0.046, respectively). In addition, univariate analysis of overall survival demonstrated that HIF-2α expression, but not HIF-1α, was related to poor outcome (P=0.001) and it retained significant in multivariate analysis (P=0.036).

Conclusions  Taken together, we conclude that HIF-1α and HIF-2α may differentially regulate the major angiogenic factors in different stages of the tumor process in NSCLC. HIF-2α may play a dominant role in tumor angiogenesis and appears to be of obvious value as a significant prognostic factor in NSCLC.

     

慢性间断缺氧对大鼠脑皮层NF-κB、ICAM-1和TNF-α表达的影响

目的 探索慢性间断性缺氧(CIH)对大鼠额顶部皮质-κB(NF-κB)、细胞间黏附分子-1(ICAM-1)和肿瘤坏死因子-α(TNF-α)表达的影响.方法 制作CIH大鼠模型.将30只SD大鼠均分为CIH组(实验组)、空气模拟对照组及空白对照组.采用免疫组织化学方法检测3组大鼠额顶部皮质NF-κB、ICAM-1和TN...     

核因子-κB与血管细胞间黏附分子-1在人冠状动脉粥样硬化斑块中的表达及其与斑块稳定性的关系

目的探讨核因子-κB(NF-κB)、血管细胞间黏附分子-1(VCAM-1)在人冠状动脉粥样硬化斑块中的表达及其与斑块稳定性之间的关系。方法从48例尸检标本中获得48个冠状动脉前降支标本。通过苏木素-伊红染色病理特征将标本分为正常对照组、稳定斑块组和不稳定斑块组。采用免疫组织化学法检测NF-κB、VCAM-1在各组冠状动脉内膜中的表达。结果正常对照组NF-κB、VCAM-1不表达,在稳定斑块组和不稳定斑块组NF-κB、VCAM-1表达增加(P<0.05),且不稳定斑块组表达高于稳定斑块组(P<0.05)。NF-κB、VCAM-1在粥样硬化冠状动脉内膜区域的表达强度呈正相关(r=0.401,P<0.05)。结论NF-κB、VCAM-1参与冠状动脉粥样硬化斑块的发生、发展并与斑块稳定性密切相关。NF-κB作为引发炎症的关键转录因子可能上调VCAM-1的表达。     

小剂量茶碱对大鼠气道平滑肌细胞表达NF-κB与ICAM-1的影响

目的:观察小剂量茶碱对培养的大鼠气道平滑肌细胞表达核因子κB(NF-κB)与细胞间黏附分子1(ICAM-1)的影响,探讨小剂量茶碱在气道发挥抗炎作用的可能机制。方法:体外培养正常大鼠鼠婴的气道平滑肌细胞,将培养出的细胞随机分为3组:空白对照组、肿瘤坏死因子α(TNF-α)刺激组、茶碱干预组。采用免疫组织化学SP法检测经TNF-α刺激的大鼠的气道平滑肌细胞中加入不同浓度的茶碱共同培养4 h,以及加入同一浓度茶碱共同培养不同时间,NF-κB活性和ICAM-1表达的变化。结果:TNF-α刺激组与空白对照组的NF-κB活性和ICAM-1表达相比较,差异均有显著性(P<0.05)。经TNF-α刺激的大鼠的气道平滑肌细胞中加入5,10,15 mg/L的茶碱共同培养4 h,NF-κB活性和ICAM-1表达均有所下降。与TNF-α刺激组相比,5 mg/L组无统计学差异(P>0.05),余两组差异均有显著性(P<0.05)。且茶碱干预组内两两比较,差异均有显著性(P<0.05)。经TNF-α刺激的大鼠的气道平滑肌细胞中加入10 mg/L茶碱共同培养2,4,24 h。与TNF-α刺激组相比,茶碱处理组的差异均有显著性(P<0.05)。但茶碱处理组内不同处理时间两两比较,差异无显著性(P>0.05)。结论:茶碱可能通过抑制气道平滑肌细胞NF-κB活性和ICAM-1的表达,进而减少炎症细胞在气道的浸润。     

Hyperbaric oxygen intervention on expression of hypoxia-inducible factor-1α and vascular endothelial growth factor in spinal cord injury models in rats

Background Hyperbaric oxygen （HBO） intervention is a main therapeutic method and the curative effect has been certified for spinal cord injury （SCI）, but the mechanisms of the neuroprotective effect of HBO on SCI remain elusive. This study aimed to observe the change in expression of hypoxia-inducible factor-1α （HIF-1α） and vascular endothelial growth factor （VEGF） after SCI at different time points and to investigate the neuroprotective mechanism of HBO on SCI in rats.     

Akt-centered amplification loop plays a critical role in vascular endothelial growth factor/stromal cell-derived factor 1-α cross-talk and cardioprotection

Background  Vascular endothelial growth factor (VEGF) is one of major mediators of angiogenesis and survival factor in some tissue, however, its direct effects on cardiomyocytes remain poorly understood.

Methods  Rat neonatal ventricular myocytes were cultured in vitro. Akt phosphorylation was measured by Western blotting; the expression of stromal cell-derived factor α (SDF-1α)/CXCR4 axis was evaluated by real-time PCR and Western blotting. LY294002 and AMD3100 were used to interfere with the signaling of VEGF and SDF-1α/CXCR4 axis. Cardiac myocytes viability and injury were evaluated by trypan blue staining and lactate dehydrogenase (LDH) release.

Results  Treatment of neonatal rat ventricular myocytes with VEGF induced phosphorylation of Akt in a dose and Flk-1 dependent manner. VEGF attenuated H₂O₂ induced cardiac myocyte death. The phosphoinositol-3-kinase (PI3K) inhibitor, LY294002 and Flk-1 antibody abolished the beneficial effects of VEGF on H₂O₂ induced cell death. In the mean time SDF-1α-CXCR4 axis was up-regulated by VEGF through PI3K-Akt signaling and contributed to the protective effects of VEGF on H₂O₂ induced cell death. Interestingly, SDF-1α also promoted production of VEGF in cultured cardiac myocytes and LY294002 reversed the up-regulation of VEGF induced by SDF-1α.

Conclusion  VEGF has direct protective effects on cardiomyocytes; a crosstalk between VEGF and SDF-1α through PI3K-Akt serves a survival role in cardiomyocytes in vitro.