EGCG 对HepG2 肝癌细胞跨内皮迁移的影响及机制研究

目的探讨表没食子儿茶素没食子酸酯(EGCG)对体外培养的人肝癌细胞系HepG2细胞跨内皮迁移的影响及其机制。方法采用癌细胞与内皮细胞的单层粘附实验检测HepG2细胞与内皮细胞的粘附;利用Transwell小室法分析HepG2细胞的跨内皮迁移;运用real time PCR检测LOX-1mRNA水平,Western Blot分析LOX-1蛋白的表达。结果 EGCG(5,10,20μM)能够浓度依赖性地抑制TNF-α(50ng·mL-1)所诱导的HepG2细胞与内皮细胞的粘附、HepG2细胞的跨内皮迁移以及LOX-1mRNA和蛋白表达的上调。LOX-1中和抗体TS20(10ng·mL-1)也能抑制TNF-α对HepG2细胞的这些效应。结论 EGCG通过减少LOX-1的表达能明显抑制TNF-α诱导的肝癌细胞与内皮细胞的粘附及跨内皮迁移。LOX-1可能作为一种粘附分子,参与介导肝癌细胞与内皮细胞的相互作用。     

黄连多糖对AGEs诱导内皮细胞增殖及其受体表达的作用研究

考察黄连多糖对高级糖基化终产物(AGEs)诱导人脐静脉内皮细胞(HUVECs)增殖和AGEs受体(RAGE)表达的作用。采用水提,Sevag法去蛋白,醇沉法获得黄连多糖(CCP);80%汇聚的HUVECs分成6组,分别为空白对照组、BSA对照组(蛋白浓度200μg/mL)、AGEs组(蛋白浓度200μg/mL)、AGEs+CCP(25μg/mL)、AGEs+CCP(50μg/mL)和AGEs+CCP(100μg/mL),采用MTT法检测黄连多糖对AGEs诱导HUVECs增殖的影响;实时荧光定量PCR检测RAGE mRNA表达;Western Blot分析RAGE蛋白表达情况。HUVECs经AGEs诱导48h后,其增殖率显著增殖。黄连多糖可以剂量依赖性的抑制AGEs诱导HUVECs早期增殖作用,定量PCR和Western Blot结果表明CCP可以在mRNA和蛋白水平抑制RAGE表达。黄连多糖可通过抑制RAGE表达,降低AGEs对内皮细胞的激活作用。     

阿托伐他汀对内皮细胞微粒诱导人脐静脉内皮细胞VCAM-1和ICAM-1表达的影响

目的:探讨阿托伐他汀对内皮细胞微粒(EMPs)诱导的人脐静脉内皮细胞(HUVECs)表达血管细胞粘附分子(VCAM)-1和细胞间粘附分子(ICAM)-1的影响。方法:取生长良好的第4,5代人脐静脉内皮细胞,将细胞分为3大组:对照组、EMPs组、EMPs+阿托伐他汀组。对照组加入培养基,EMPs组以不同浓度的EMPs(0/mL,1×102/mL,1×103/mL,1×104/mL,1×105/mL)与HUVECs共同孵育24 h,EMPs+阿托伐他汀组以不同浓度的阿托伐他汀(0.05,0.1,1.0,10μmol.L-1)与HUVECs作用1 h后,加入105/mL EMPs共同孵育24 h。分别采用实时荧光定量聚合酶链反应和蛋白免疫印迹方法检测VCAM-1和ICAM-1 mRNA和蛋白的表达。结果:HUVECs受EMPs刺激后,VCAM-1和ICAM-1 mRNA及蛋白表达呈浓度依赖性增加,阿托伐他汀可不同程度上抑制EMPs的作用。结论:阿托伐他汀抗动脉粥样硬化作用可能部分与抑制EMPs诱导的内皮细胞VCAM-1和ICAM-1的表达有关。     

蒙花苷对TNF-α诱导的血管内皮细胞炎症损伤及TLR4/IκBα/NF-κB信号通路的影响

目的 以肿瘤坏死因子(TNF-a)刺激人脐静脉内皮细胞(EA.hy926),体外模拟血管内皮细胞炎症损伤模型,探讨蒙花苷(Buddleoside,BUD)对血管内皮细胞的保护作用和机制。方法 MTT法检测TNF-a和蒙花苷对EA.hy926细胞活性的影响;采用TNF-a(50 ng.mL_-1)刺激EA.hy926细胞,加入不同浓度(5、15和25 mmol.L_-1)蒙花苷处理,DAPI染色法测定EA.hy926细胞与单核细胞(THP-1)的黏附能力;Western Blot法检测细胞中Toll样受体(TLR4)、核因子-kB抑制蛋白(IκB-α)、核因子-kB(NF-kB)、细胞间黏附分子-1(ICAM-1)和血管细胞黏附分子-1(VCAM-1)等蛋白表达;RT-PCR法检测ICAM-1、VCAM-1等基因mRNA的表达;ELISA法检测细胞上清液中白介素-1(IL-1)、白介素-6(IL-6)和白介素-8(IL-8)的含量。结果 蒙花苷可显著抑制TNF-a刺激EA.hy926细胞与THP-1细胞间黏附作用,降低EA.hy926细胞分泌的炎症因子IL-1、IL-6和IL-8水平。Western blot和RT-PCR结果表明蒙花苷能减少EA.hy926细胞中TLR4、NF-kB、ICAM-1、VCAM-1的蛋白表达量及ICAM-1、VCAM-1 mRNA的表达量,同时能升高细胞中IκB-α的蛋白表达量。结论 蒙花苷能缓解血管内皮细胞炎症损伤,其作用机制可能主要是通过抑制TLR4/IΚBα/NF-κB信号通路发挥效用。     

六味地黄方含药血清对H_2O_2致HUVECs损伤的保护作用

目的研究六味地黄方(LWDHF)含药血清对过氧化氢(H2O2)损伤的人脐静脉血管内皮细胞(HUVECs)的保护作用,并阐明其可能的机制。方法采用400μmol·L-1H2O2复制HUVECs损伤模型,LWDHF含药血清分为3个剂量干预组(体积分数为5%、10%、20%);MTT法测定细胞活力,Hoechst染色荧光显微镜观察细胞凋亡形态,Annexin VFITC/PI双染法流式细胞仪检测细胞凋亡情况,RT-PCR法检测Bax、Caspase-3等基因mRNA表达,Western blot法检测Caspase-3、Bax等蛋白表达。结果 LWDHF含药血清能明显促进H2O2损伤后的HUVECs增殖;Hoechst染色和Annexin V-FITC/PI双染法结果均显示LWDHF含药血清抑制血管内皮细胞凋亡;RT-PCR和Western blot结果提示LWDHF抑制H2O2所致的血管内皮细胞凋亡可能是通过降低Caspase-3、Bax mRNA和蛋白的表达,升高Bcl-2 mRNA和蛋白表达实现的。结论 LWDHF含药血清可以抑制H2O2诱导的细胞凋亡,对血管内皮细胞具有一定的保护作用。     

冬凌草甲素下调STAT3-HKⅡ通路诱导HepG2细胞凋亡的研究

目的研究冬凌草甲素(Oridonin)诱导HepG2细胞凋亡的作用和机制。方法采用MTT法检测HepG2细胞的增殖;Hoechst 33342/PI双染法检测细胞凋亡;RT-PCR检测STAT3和HK-ⅡmRNA水平;Western blot检测STAT3、pSTAT3和HK-Ⅱ蛋白表达。结果冬凌草甲素可降低STAT3和HK-Ⅱ的mRNA及蛋白表达水平,剂量依赖性抑制HepG2细胞生长,促进细胞凋亡;STAT3 siRNA可下调HK-Ⅱ水平;冬凌草甲素诱导的细胞增殖抑制及凋亡可被STAT3siRNA和3-BrPA消除。结论冬凌草甲素可能通过抑制STAT3-HK-Ⅱ通路诱导HepG2细胞凋亡。     

LOX-1对氧化低密度脂蛋白所诱导的PAI-1基因表达的影响

目的探讨血凝素样氧化型低密度脂蛋白受体(LOX)-1对氧化低密度脂蛋白(ox-LDL)所诱导1型纤溶酶原激活物抑制剂-1(PAI-1)表达的影响。方法不同浓度ox-LDL培养人脐静脉内皮细胞(HUVECs),采用倒置显微镜观察内皮细胞形态变化,通过反转录-聚合酶链反应(RT-PCR)测定LOX-1、PAI-1mRNA表达,Westernblot、酶联免疫吸附试验(ELISA)分别测定LOX-1、PAI-1蛋白的表达。结果不同浓度ox-LDL组,LOX-1和PAI-1mRNA和蛋白的表达明显增加,且呈浓度依赖性(P<0.01);用250μg/mLPoly(Ⅰ)与HUVECs预先作用2h后,再加入50μg/ml的ox-LDL培养24h,与未加Poly(Ⅰ)相比,LOX-1和PAI-1mRNA和蛋白的表达明显减少(P<0.05)。结论ox-LDL可以调节培养的脐静脉内皮细胞LOX-1和PAI-1表达;LOX-1作为ox-LDL特异性受体,介导了ox-LDL诱导脐静脉内皮细胞表达LOX-1。同时该实验提示了ox-LDL诱导脐静脉内皮细胞表达PAI-1是通过LOX-1介导的。     

花青素通过TLR4/NF-κB通路对脂多糖诱导的血管内皮损伤的保护作用

目的探讨花青素(PC)对脂多糖(LPS)作用下血管内皮细胞损伤的影响及作用机制。方法体外培养人脐静脉血管内皮细胞,脂多糖作用于人脐静脉血管内皮细胞诱导其损伤,设置空白对照组、模型组(1000 ng/ml脂多糖处理)、不同浓度(100,50,25μg/ml)花青素组。使用MTT法检测各组细胞活力;ELISA检测各组细胞培养液中NO、TNF-α和IL-6的浓度变化;特定试剂盒检测乳酸脱氢酶(LDH)、丙二醛(MDA)、超氧化物歧化酶(SOD)、还原型谷胱甘肽(GSH-PX)含量;DHE荧光探针检测ROS的变化;Western blot法检测各组TLR4/NF-κB蛋白表达水平。结果与空白对照组相比脂多糖损伤组能够降低HUVECs的活力,增加ROS的含量,LDH、MDA含量显著增加,SOD、GSH-PX活性显著下降,同时降低NO分泌,诱导TNF-α和IL-6分泌及增加了TLR4/NF-κB的表达(P<0.01)。不同浓度花青素和脂多糖同时作用HUVECs时,细胞活力逐渐上升,ROS含量逐渐下降,LDH、MDA含量逐渐下降,SOD、GSH-PX活性随之上升,同时NO分泌增加,TNF-α和IL-6分泌及TLR4/NF-κB蛋白表达显著下降(P<0.01)。结论花青素能够提升脂多糖作用下HUVECs活力,恢复细胞分泌功能,增强细胞抗氧化能力,减少细胞的炎性反应;花青素可能部分地通过TLR4/NF-κB通路对血管内皮细胞发挥保护作用。     

熊果酸通过下调环氧化酶2表达调控舌鳞癌细胞增殖与凋亡

目的 研究熊果酸(UA)对舌鳞癌细胞增殖与凋亡的作用及其可能机制.方法 人舌鳞癌细胞Tca8113分别加入UA 0、10、20、40 μmol/L,培养12-72 h,采用MTT法检测细胞增殖,Hoechst 33342染色观察细胞凋亡的形态学变化,Western blot法检测药物作用后细胞中环氧化酶2(COX-2)、B细胞淋巴瘤-白血病2(Bcl-2)、Bcl相关X蛋白(Bax)及半胱天冬氨酸蛋白酶3(Caspase-3)的蛋白表达.结果 UA呈剂量依赖性地抑制舌鳞癌细胞Tca8113增殖,诱导舌鳞癌细胞凋亡,下调Tca8113细胞中COX-2蛋白表达,上调Bax/Bcl-2比值及活化的Caspase-3蛋白表达.结论 UA可能通过下调COX-2的表达抑制舌鳞癌细胞增殖,诱导凋亡.     

外源性硫化氢抑制ox-LDL诱导血管内皮细胞组织因子的表达与降低ROS产生和抑制NF-κB活化有关

目的探讨外源性硫化氢抑制氧化型低密度脂蛋白(ox-LDL)诱导内皮细胞组织因子(TF)表达的机制。方法分别用不同浓度NaHS(25、50、100和200μmol·L-1)和50mg·L-1ox-LDL孵育人脐静脉内皮细胞(HUVECs),用RT-PCR和ELISA法检测HUVECs TF mRNA表达和蛋白含量,DCFH法测细胞内活性氧(ROS)的含量,Western blot测核蛋白转录因子(NF-κB)的活化。结果 ox-LDL明显诱导HUVECs TF mRNA的表达和蛋白含量增加;细胞内ROS水平升高,NF-κB活化。NaHS明显抑制了ox-LDL对TF mRNA和蛋白表达的诱导作用,同时降低ox-LDL诱导的细胞内ROS生成和NF-κB活化。此外,NF-κB抑制剂BAY 11-7082(10μmol·L-1)或抗氧化剂N-乙酰半胱氨酸(1 mmol·L-1)也能抑制ox-LDL诱导TF mRNA表达和蛋白含量的增加,同时降低细胞内ROS生成和NF-κB活化,该作用与200μmol·L-1NaHS的效应相似。结论 NaHS抑制ox-LDL诱导内皮细胞TF的表达与降低ROS产生和抑制NF-κB活化有关。     

Ursolic acid suppresses IL-6 induced C-reactive protein expression in HepG2 and protects HUVECs from injury induced by CRP

ObjectiveTo investigate the inhibitory effects of ursolic acid (UA) on the expression of C-reactive protein (CRP) induced by IL-6 in HepG2 cells and the protective effects on the CRP-induced injury to human umbilical vein endothelial cells (HUVECs).MethodsHepG2 cells were treated with IL-6 or IL-6 and different concentrations of UA for 48 h, then the cells were collected. The total protein and RNA of the cells were extracted for western blotting and RT-PCR methods to detect CRP protein and mRNA expression. HUVECs were treated with CRP or CRP and different concentrations of UA for 24 h. Cell proliferation in each group was assayed by MTT. Cells were collected for western blotting and RT-PCR methods to detect VCAM-1, LOX-1 protein or mRNA expression.ResultIL-6 can significantly increase CRP protein and mRNA expression in HepG2 cells, and this effect of IL-6 can be decreased by UA (6.25, 12.5, 25 μmol/L) markedly in a dose-dependent manner. UA can inhibit CRP-induced proliferation of HUVECs. CRP can obviously increase LOX-1/VCAM-1 expression in HUVECs, both on mRNA and protein levels and the effect of CRP can be inhibited by UA (5, 10, 20 μmol/L) in a dose-dependent manner.ConclusionUA can reduce the over expression of CRP in HepG2 cells induced by IL-6 and inhibit the increased expression of VCAM-1 and LOX-1 in HUVECs caused by CRP. Our research suggests that UA can reduce CRP levels in plasma and prevent inflammatory cytokines from injuring endothelial cells by inhibiting the hepatic synthesis of CRP. So UA may have positive significance for prevention and treatment of atherosclerosis and other cardiovascular diseases.     

Impact of simvastatin and losartan on antiinflammatory effect: in vitro study

Antiinflammatory properties of losartan are currently unclear. This study tested the hypothesis that losartan itself has an antiinflammatory effect comparable to that of simvastatin. Human umbilical vein endothelial cells (HUVECs) were (1) incubated with culture medium alone, (2) incubated with added C-reactive protein (CRP) (25, 50, 75, and 100 microg/mL) for stimulation, and (3) pretreated with losartan (stepwise increased dose: 100, 300, 500, and 750 micromol/L) and simvastatin (stepwise increased dose: 25, 50, 75, and 100 micromol/L) for 4 hours before adding CRP for stimulation. Surface expression of vascular cell adhesion molecule-1 (VCAM-1) was determined by flow cytometry. Supernatant levels of monocyte chemoattractant protein-1 (MCP-1) and interleukin-6 (IL-6) were measured by ELISA. Experimental results showed that the effect of CRP on VCAM-1 expression and supernatant levels of MCP-1 and IL-6 increases stepwise as CRP concentrations increase from 25 to 50 to 75 to 100 microg/mL (all P < 0.001). The effect of CRP on VCAM-1 expression in HUVECs and supernatant levels of MCP-1 and IL-6 were significantly suppressed by 25 micromol/L simvastatin with stepwise increased suppression as simvastatin dose increased to 50, 75, and 100 micromol/L (all P < 0.0001). However, losartan did not significantly suppress CRP's effect on VCAM-1 expression in HUVECs (P > 0.5). Moreover, losartan did not suppress CRP's effect on MCP-1 and IL-6 secretion unless a high dose (> or =500 micromol/L) of losartan was used. Compared with simvastatin, losartan had less effect on suppression of CRP-mediated inflammation.     

原发性高血压患者血清IL-6和C-反应蛋白水平的研究

目的：探讨在原发性高血压患者中,血清C-反应蛋白（CRP）和白细胞介素-6（IL-6）水平变化及意义。方法：选择42例正常血压人群和36例原发性高血压患者,常规测量血压,抽取空腹静脉血检测其血糖、血脂、胰岛素、IL-6、CRP。结果：与正常人群相比,在高血压患者中,血清总胆固醇、三酰甘油、空腹胰岛素、IL-6水平（14.56±5.36vs23.16±2.43μg/ml,P〈0.05）、CRP（1.52±1.04vs2.05±1.47mg/ml,P〈0.05）水平均高于正常血压人群。在原发性高血压患者中,血清IL-6、CRP水平均与体重指数、收缩压正相关。结论：原发性高血压患者中血清IL-6、CRP水平增高并与收缩压正相关,提示原发性高血压与炎症密切相关。     

罗仙子提取物对单核细胞与血管内皮细胞黏附的影响

目的：考察罗仙子提取物对单核细胞与血管内皮细胞黏附的影响。方法：制备相对分子质量30000以下罗仙子提取物;考察罗仙子提取物对血管内皮细胞EA．hy926活力的影响;肿瘤坏死因子（TNF-α）诱导建立单核细胞THP-1和EA．hy926黏附模型,采用虎红染色,考察不同浓度罗仙子提取物对EA．hy926与THP-1黏附性的影响;采用ELISA考察罗仙子提取物对TNF-α诱导的EA．hy926分泌单核细胞趋化蛋白-1（MCP-1）和血管细胞黏附分子-1（VCAM-1）的影响。结果：罗仙子提取物（浓度≤4×102μg／mL时）对EA．hy926未见明显的增殖或抑制作用（P〉0．05）;罗仙子提取物（浓度≥6．25μg／mL时）可浓度依赖性降低两细胞之间的黏附作用;罗仙子提取物各浓度均能显著地降低TNF-α诱导的MCP-1表达（P〈0．01）,罗仙子提取物（浓度≥50μg／mL时）可显著地降低TNF-α诱导的VcAM-1的表达（P〈0．01）。结论：罗仙子提取物可通过抑制TNF-α诱导的内皮细胞分泌MCP-1和VCAM-1,阻滞单核细胞与血管内皮细胞之间的黏附作用,从而发挥抗动脉粥样硬化作用。     

阿托伐他汀与氨氯地平对ox-LDL损伤的人脐静脉内皮细胞LOX-1和eNOS表达的影响

目的以人脐静脉内皮细胞(HUVECs)为载体,探讨阿托伐他汀与氨氯地平对氧化低密度脂蛋白(ox-LDL)损伤的HUVECs内血凝素样氧化型低密度脂蛋白受体(LOX-1)和内皮型一氧化氮合酶(eNOS)表达的影响。方法体外培养HUVECs,采用倒置显微镜观察内皮细胞形态变化,待细胞生长至融合状态时加入ox-LDL、阿托伐他汀、氨氯地平进行干预。随机分为:①对照组(培养基);②ox-LDL组(50mg/L);③阿托伐他汀组(10μmol/L);④氨氯地平组(10μmol/L);⑤阿托伐他汀+氨氯地平组。应用实时荧光定量聚合酶链反应(RT-PCR)检测各组LOX-1mRNA与eNOSmRNA表达的水平。结果与正常对照组比较,ox-LDL使LOX-1mRNA表达增加,eNOSmRNA表达减少;阿托伐他汀、氨氯地平均可使ox-LDL损伤的HUVECs内LOX-1mRNA表达下调,eNOSmRNA表达上调,且二者具有协同作用;混合刺激组与对照组比较,LOX-1mRNA、eNOSmRNA表达差异均无统计学意义(P>0.05)。结论阿托伐他汀和氨氯地平均可下调ox-LDL损伤的HUVECs内LOX-1mRNA的表达,上调eNOSmRNA的表达,且二者具有协同作用。     

苯扎贝特对内皮细胞LOX-1及抗凋亡基因Bcl-2影响

目的研究苯扎贝特对氧化型低密度脂蛋白(ox-LDL)作用的人脐静脉内皮细胞(HUVECs)血凝素氧化型低密度脂蛋白受体-1(LOX-1)及抗凋亡基因Bcl-2的影响。方法体外培养HUVECs,反转录聚合酶链反应(RT-PCR)观察各组LOX-1及Bcl-2 mRNA的变化,Western-blot方法观察各组Bcl-2蛋白的变化。结果ox-LDL组与正常对照组比较LOX-1表达显著增加(P<0.05),抗凋亡基因Bcl-2表达降低(P<0.05),苯扎贝特组LOX-1 mRNA表达减少(P<0.05),Bcl-2 mRNA和蛋白表达增加(P<0.05)且呈浓度效应依赖关系。结论苯扎贝特可通过下调LOX-1的表达,上调抗凋亡基因Bcl-2表达从而抑制ox-LDL引起的内皮细胞凋亡。     

Protective effect of α-lipoic acid on oxidized low density lipoprotein-induced human umbilical vein endothelial cell injury

The present study investigated the effect and possible mechanisms of α-lipoic acid (LA) in preventing endothelial cell injury induced by oxidized low-density lipoprotein (oxLDL). A model of human umbilical vein endothelial cell (HUVEC) injury was established by incubating the HUVECs with 200 μg/ml oxLDL. HUVECs were pre-treated with 0.1, 0.2 or 0.5 mmol/l of LA in the presence of oxLDL for 24 h. Apoptosis and cellular surface ceramide content were investigated separately by flow cytometry and by LC-MS/MS. LOX-1, Bcl-2 and CRP protein expression levels were evaluated by western blotting. LOX-1 mRNA expression was evaluated by RT-PCR assay. The results showed that oxLDL induced cytotoxicity in both concentration-dependent and time-dependent manners. LA boosted the cell survival rate and significantly reduced the content of MDA and lactate dehydrogenase (LDH) leakage. Apoptotic rates were significantly reduced by the addition of LA compared to oxLDL group. LA might also have inhibited ceramide generation induced by oxLDL in a dose-dependent manner. Furthermore, LA down-regulated LOX-1 protein and mRNA expression and up-regulated Bcl-2 protein expression levels in a dose-dependent manner. Expression of CRP protein was weak and undetectable. These results suggested that LA exhibited cytoprotective effects against oxLDL by decreasing apoptotic rates and decreasing cellular surface ceramide content, two effects that are related to decreased LOX-1 expression, and also by stimulating the expression of Bcl-2 protein. The cytoprotective effects are not thought to be due to inhibited C-reactive protein (CRP) protein expression in HUVECs.     

雷公藤红素对小鼠的免疫抑制作用及其对IL-6mRNA表达影响的研究

目的：研究雷公藤红素对小鼠的免疫抑制作用及对细胞因子IL-6mRNA表达的影响。方法：采用碳粒廓清、迟发型变态反应、血清溶血素测定和T淋巴细胞转化实验，观察雷公藤红素对小鼠免疫功能的影响；运用RT—PCR半定量法研究雷公藤红素对小鼠肝脏IL-6mRNA表达影响。结果：雷公藤红素能抑制小鼠血清溶血素水平（400μg／kg），且与剂量呈依赖关系；小鼠耳廓肿胀度研究表明，雷公藤红素能使迟发型变态反应程度减轻（400μg／kg）；雷公藤红素剂量在0．25μg／mL时，可以明显抑制植物血凝素（PHA）诱导的细胞增殖；雷公藤红素800μg／kg能对抗CCl4引起的急性肝损伤小鼠肝脏IL-6mRNA含量的升高。结论：雷公藤红素在一定程度上能抑制小鼠的免疫功能，能抑制炎症细胞因子IL-6基因的过度表达．