扇贝多肽在中波紫外线诱导的HaCaT细胞凋亡中对p38MAPK-HSP27通路的影响

目的从p38MAPK-HSP27通路方面研究扇贝多肽(polypeptide from Chlamys farreri,PCF)抑制中波紫外线(UVB)诱导的HaCaT细胞凋亡的作用机制。方法复制UVB诱导的HaCaT细胞凋亡模型;实验设计为6组:对照组、UVB模型组、UVB+5.69mmol.L-1维生素C阳性对照组、UVB+5.69mmol.L-1PCF组、UVB+2.84mmol.L-1PCF组、UVB+1.42mmol.L-1PCF组。PCF预处理30min,荧光染色(Hoechst33258)结合琼脂糖凝胶电泳分析PCF在p38抑制剂(SB203580)存在和不存在两种条件下对UVB诱导的HaCaT细胞凋亡的影响;蛋白质印迹法检测p38MAPK、HSP27的表达及磷酸化水平的改变,同时分析HSP27在细胞内定位的改变。结果PCF可明显抑制UVB诱导的HaCaT细胞凋亡;PCF在1.42~5.69mmol.L-1范围内,可剂量依赖性抑制p38MAPK和HSP27的磷酸化水平,并抑制HSP27由胞质向胞核中的移位。结论PCF通过阻断p38MAPK-HSP27通路来抑制UVB诱导的HaCaT细胞凋亡,其作用机制与抑制p38MAPK的活化从而阻止HSP27的磷酸化及其细胞内移位有关。     

扇贝多肽经由死亡受体和线粒体通路抑制UVB诱导的HaCaT细胞凋亡

目的从凋亡相关分子Fas(CD95)、半胱天冬酶-3(caspase-3)和活性氧(ROS)、细胞色素C的角度,研究扇贝多肽(polypeptide fromChlamys farreri,PCF)抑制UVB引起的人角质HaCaT细胞凋亡的分子机制。方法实验设计为5组:对照组、UVB模型组、UVB+5.69mmol.L-1PCF组、UVB+2.84mmol.L-1PCF组、UVB+1.42mmol·L-1PCF组。应用小干扰RNA(siRNA)干扰UVB辐射的HaCaT细胞的Fas表达;琼脂糖凝胶电泳分析Fas siRNA及ROS清除剂NAC对细胞凋亡的影响;以DCFH-DA为荧光探针,检测细胞内ROS的含量;免疫印迹法检测细胞色素C及用RNAi干扰降低Fas表达后caspase-3的表达。结果干扰Fas后,UVB辐射的HaCaT细胞凋亡受到明显抑制及caspase-3的表达降低;NAC对UVB诱导的HaCaT细胞凋亡有抑制作用;1.42~5.69mmol.L-1剂量范围内的PCF可剂量依赖性抑制UVB引起的ROS的生成及细胞色素C的释放。结论PCF可抑制UVB诱导的HaCaT细胞凋亡,其作用机制与抑制Fas-caspase-3及ROS-细胞色素C通路有关。     

扇贝多肽对UVA损伤HaCaT细胞UCP2表达及线粒体功能的影响

目的探究紫外线A(ultraviolet A,UVA)损伤对HaCaT角质形成细胞线粒体解偶联蛋白2(uncoupling protein2,UCP2)表达的影响以及扇贝多肽(polypeptide from Chlamysfarreri,PCF)的调节作用,并研究PCF对UVA损伤HaCaT细胞线粒体功能的保护作用。方法复制8 J.cm-2 UVA辐射损伤HaCaT角质形成细胞模型,免疫印迹法检测UVA损伤后HaCaT细胞UCP2蛋白表达的变化及PCF的影响、PCF对UVA损伤HaCaT细胞凋亡蛋白酶激活因子(apoptot-ic protease-activating factor 1,Apaf-1)、细胞色素C(Cyto-chrome C,Cyt C)蛋白表达的影响;电子自旋共振(electronspin resonance,ESR)技术检测ROS的释放量;流式细胞术检测线粒体膜电位;紫外分光光度法测定PCF对UVA损伤HaCaT细胞线粒体呼吸链复合酶Ⅰ(NADH-辅酶Q还原酶)活性的影响。结果正常HaCaT细胞UCP2几乎不表达,UVA照射后表达升高,3 h达高峰,6 h开始逐渐下降;1.42～5.69 mmol.L-1剂量范围内的PCF对UCP2的表达有抑制作用;PCF可明显抑制UVA诱导的ROS产生、线粒体膜电位下降、Cyt C的释放及Apaf-1的表达,可有效抑制UVA损伤后HaCaT细胞呼吸链复合酶I活性的下降。结论 PCF对UVA引起的HaCaT细胞线粒体损伤具有保护作用。     

热休克蛋白70抑制剂PFTμ对炎症反应的影响

目的:观察热休克蛋白70抑制剂PFTμ与脂多糖诱导RAW264.7细胞及缺血再灌注损伤小鼠炎症反应的关系,以探讨其影响和可能的作用机制。方法:采用脂多糖(LPS)诱导的RAW264.7细胞株建立细胞炎症反应模型,采用Griess试剂法测定一氧化氮(NO)释放量;采用Western-Blot法测定目的蛋白表达;采用反转录聚合酶链反应(RT-PCR)分析诱生型一氧化氮合酶(iNOS)mRNA表达改变;建立小鼠心脏缺血再灌注(I/R)炎症反应模型,测定小鼠心肌梗死面积。结果:热休克蛋白70抑制剂PFTμ可抑制LPS诱导的RAW264.7细胞NO的释放;下调iNOS蛋白和mRNA表达;早期可抑制IκBα蛋白的表达。同时,可减少缺血再灌注小鼠心肌梗死面积。结论:PFTμ有抑制炎症反应的作用,其作用机制可能是通过抑制一氧化氮的生成而发挥的。     

HSP70抑制剂PFTμ对干扰素γ诱导的iNOS表达的研究

目的观察热休克蛋白70抑制剂PFTμ对干扰素γ(IFN-γ)诱导的RAW 264.7细胞一氧化氮(NO)的生成及诱生型一氧化氮合酶(iNOS)表达的作用。方法采用IFN-γ诱导的RAW 264.7细胞株建立细胞炎症反应模型,采用Griess试剂法测定细胞NO释放量;采用Western blot法测定相应目的蛋白的表达;采用反转录聚合酶链反应(RT-PCR)分析iNOS mRNA表达的变化。建立小鼠心脏缺血/再灌注(I/R)模型,分为对照组和给药组,测定小鼠心肌梗死面积的变化。结果 PFTμ可抑制IFN-γ诱导的RAW264.7细胞NO的生成、i NOS蛋白及mRNA表达。其作用机制可能是通过部分抑制RAW264.7细胞核内的IRF-1蛋白表达。PFTμ可减少缺血/再灌注小鼠心脏梗死面积(P<0.05)。结论PFTμ可通过部分抑制细胞核内IRF-1蛋白表达而发挥抗炎症反应的作用。     

芦荟大黄素对LPS诱导的RAW264.7细胞NO生成及iNOS表达的影响

目的观察芦荟大黄素(aloe-emodin)对脂多糖(LPS)诱导的RAW264.7细胞一氧化氮(NO)生成及诱生型一氧化氮合酶(iNOS)mRNA表达的作用。方法采用LPS诱导的RAW264.7细胞株建立细胞炎症反应模型。采用Griess试剂法测定NO释放量;采用硝普钠释放NO法测定NO自由基含量的变化;采用反转录聚合酶链反应(RT-PCR)分析iNOS mRNA表达改变。结果芦荟大黄素在0.69～2.50mg·L-1剂量范围内可抑制LPS诱导的RAW264.7细胞NO的释放,并呈剂量和时间依赖关系;芦荟大黄素在0.63～5.00mg·L-1剂量范围内可下调LPS诱导的RAW264.7细胞iNOS mRNA含量;而此范围内芦荟大黄素无直接清除NO自由基作用,不影响iNOS活性。结论芦荟大黄素可明显降低LPS诱导的RAW264.7细胞NO释放,呈时间和剂量依赖关系,此作用并非通过捕捉NO或抑制iNOS活性来实现,而是通过抑制iNOS mRNA表达发挥作用的。     

肿瘤坏死因子相关凋亡诱导配体及扇贝多肽在UVA诱导HaCaT细胞凋亡中的作用

目的研究UVA对HaCaT细胞肿瘤坏死因子相关凋亡诱导配体(tumour necrosis factor related apoptosis inducing ligand,TRAIL)表达的影响;复制UVA诱导的HaCaT细胞凋亡模型,探究TRAIL在UVA诱导的HaCaT细胞凋亡中的作用及扇贝多肽(Polypeptide from Chlamys farreri,PCF)对UVA诱导的TRAIL凋亡通路的影响。方法实验设计分为5组:对照组、UVA模型组、UVA+5.69mmol·L-1PCF组、UVA+2.84mmol·L-1PCF组、UVA+1.42mmol·L-1PCF组。Real-TimePCR检测TRAIL mRNA表达;蛋白质印迹法检测TRAIL蛋白表达及caspase-8活性;琼脂糖凝胶电泳分析TRAIL中和性抗体对UVA诱导的HaCaT细胞凋亡的影响。结果8J·cm-2UVA照射HaCaT细胞后TRAIL mR-NA及蛋白表达增加,与对照组相比差异有显著性(P<0.01);TRAIL中和性抗体对UVA诱导的HaCaT细胞凋亡有抑制作用;1.42~5.69mmol·L-1剂量范围内的PCF可剂量依赖性抑制UVA引起的HaCaT细胞TRAIL mRNA及蛋白表达(P<0.05,P<0.01);PCF对UVA引起的HaCaT细胞caspase-8的活化有抑制作用,且呈量效关系。结论UVA可增强HaCaT细胞TRAIL表达;TRAIL参与了UVA诱导的HaCaT细胞凋亡;PCF对UVA诱导的HaCaT细胞TRAIL表达有抑制作用,也可减弱UVA诱导的caspase-8活化,以其抗氧化活性抑制TRAIL凋亡通路而发挥抗凋亡作用。     

热休克蛋白70激动剂SW02对脂多糖诱导的巨噬细胞iNOS表达的调控及机制

目的观察热休克蛋白70(Hsp70)激动剂SW02对脂多糖(LPS)诱导的RAW264.7细胞诱导型一氧化氮合酶(iNOS)表达及一氧化氮(NO)生成的作用,并探讨其作用机制。方法采用LPS诱导RAW264.7细胞建立细胞炎症模型,将细胞随机分为DMSO组、DMSO+LPS(1 mg·L~(-1))组、SW02组和SW02+LPS(1 mg·L(-1))组。Western blot法测定蛋白表达;Griess试剂法测定NO含量;实时定量PCR法测定iNOS mRNA表达;染色质免疫共沉淀法(ChIP)检测核因子κB(NF-κB)与iNOS启动子结合能力变化。结果 SW02明显抑制由LPS诱导的RAW264.7细胞iNOS蛋白、mRNA表达和NO释放(SW02+LPS组iNOS表达量和NO生成量明显低于DMSO+LPS组,P<0.01或P<0.05);SW02不影响由LPS诱导的RAW264.7细胞κB-α抑制子(IκB-α)降解(SW02+LPS组IκB-α表达量与DMSO+LPS组比差异无显著性,P>0.05)和NF-κB入核(SW02+LPS组细胞质、细胞核NF-κB表达量与DMSO+LPS组比差异无显著性,P>0.05);SW02明显抑制由LPS诱导的NF-κB与iNOS启动子结合(SW02+LPS组NF-κB与iNOS启动子结合量明显低于DMSO+LPS组,P<0.05)。结论 SW02抑制巨噬细胞iNOS表达和NO生成,其机制可能与抑制NF-κB与iNOS启动子结合有关。     

细胞因子对膀胱平滑肌细胞内诱导性一氧化氮合酶的激活作用(英文)

探讨肿瘤坏死因子α (TNFα)和γ干扰素(INFγ)对大鼠膀胱平滑肌细胞诱导性一氧化氮合酶(iNOS )的影响 .将TNFα (1nmol·L- 1)或INFγ(5 0kU·L- 1)分别或同时加入膀胱平滑肌细胞培养液 ,2 4h后测定细胞培养液中一氧化氮 (NO)水平 ,并用Western印迹方法检测iNOS的表达 .结果显示 ,TNFα或INFγ单独不能诱导iNOS表达 ,也不能引起NO水平显著提高 .但当TNFα和INFγ联合诱导细胞 2 4h ,则细胞培养液中NO水平明显升高 ,用Western印迹分析可见iNOS表达 ,说明TNFα和INFγ具有协同诱导作用 .在TNFα和INFγ加入膀胱平滑肌细胞前 30min ,加入NOS抑制剂L 氮 精氨酸甲酯 (L NAME) ,可显著抑制TNFα和INFγ对NO的生成诱导 .结果提示 ,TNFα和INFγ联合应用可激活膀胱平滑肌细胞iNOS .     

白藜芦醇对中波紫外线致人角质形成细胞损伤的防护作用

目的:研究白藜芦醇(resveratrol,Res)对中波紫外线(UVB)照射体外培养的人永生化角质形成细胞(HaCaT)的损伤的保护作用。方法:体外培养HaCaT细胞,MTT法检测不同浓度Res对HaCaT细胞增殖活性的影响。UVB照射及Res处理24 h后,采用RT-PCR方法测定细胞中MMP-1,MMP-9和TIMP-1mRNA的相对含量。结果:UVB 30 mJ.cm-2照射后,HaCaT细胞产生的MMP-9 mRNA含量显著增加(P<0.05),TIMP-1 mRNA明显减少(P<0.05);UVB 90 mJ.cm-2照射HaCaT细胞后其MMP-1 mRNA增加(P<0.05)。与UVB照射组相比较,0.5 mmol.L-1Res能显著抑制UVB诱导的HaCaT细胞产生的MMP-1,MMP-9 mRNA含量增加以及UVB对TIMP-1 mRNA的抑制作用(P<0.05)。结论:Res可以显著抑制UVB照射诱导的HaCaT细胞产生的MMP-1,MMP-9及TIMP-1 mRNA含量的变化,对皮肤光老化可有一定的防护作用。     

扇贝多肽对UVB损伤HaCaT细胞的抗氧化作用

目的研究扇贝多肽(PCF)对UVB损伤HaCaT细胞的抗氧化作用。方法HaCaT细胞与PCF孵育1h后，接受UVB辐射，继续孵育18h后，采用酶化学法测定细胞超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH—Px)、过氧化氢酶(CAT)活性、以及测定其总抗氧化能力(T—AOC)、丙二醛(MDA)水平。结果PCF能提高HaCaT细胞内抗氧化酶SOD，GSH—Px，CAT活性，增强细胞总抗氧化能力并减少脂质过氧化产物MDA的产生。结论PCF能增加细胞内抗氧化酶活性，抑制脂质过氧化反应，具有抗氧化作用。     

Chloroquine induces the expression of inducible nitric oxide synthase in C6 glioma cells.

Chloroquine, a well-known lysosomotropic agent, has long been used for the treatment of malaria and rheumatologic disorders. However, therapeutic doses of chloroquine are known to cause behavioral side effects. In the present study, we investigated whether chloroquine stimulates inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) synthesis in C6 glioma cells. Chloroquine caused dose-dependent increase in iNOS protein expression and NO production in C6 glioma cells. A tyrosine kinase inhibitor (genistein), a protein kinase C (PKC) inhibitor (Ro 31-8220), and a p38 mitogen-activated protein kinase (MAPK) inhibitor (SB 203580) all respectively suppressed chloroquine-induced iNOS expression and NO release from C6 glioma cells. Chloroquine activates p38 MAPK and stimulates PKC-alpha and -delta translocation from the cytosol to the membrane in C6 glioma cells. Chloroquine-stimulated p38 MAPK activation was blocked by genistein (20 microM), Ro 31-8220 (3 microM), and SB 203580 (10 microM). Incubation of lipopolysaccharide (LPS)-stimulated cells with chloroquine at non-toxic concentrations (10-100 microM) for 48 h increased iNOS expression, and led to a significant loss of adherent cells. Induction of DNA fragmentation in floating cells indicated that the C6 glioma cells were undergoing apoptosis. Taken together, our data suggest that chloroquine may activate tyrosine kinase and/or PKC to induce p38 MAPK activation, which in turn induces iNOS expression and NO production.     

Inhibitory effects of a fermented ginseng extract, BST204, on the expression of inducible nitric oxide synthase and nitric oxide production in lipopolysaccharide-activated murine macrophages

In this study, the effects of BST204, a fermented ginseng extract, on the expression of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) production are looked into. Crude ginseng extract was incubated with ginsenoside-beta-glucosidase to prepare BST204. BST204, unlike lipopolysaccharide (LPS) and crude ginseng extract, did not affect the level of iNOS protein and NO production in unstimulated RAW 264.7 cells. However, it suppressed the level of iNOS protein and NO production in LPS-stimulated RAW 264.7 cells but did not manifest the same effect on the iNOS mRNA level. An investigation of the activating phosphorylation of p70 S6 kinase and 4E-BP1, which are important for translation, was conducted to investigate the suppressive mechanism of iNOS protein. LPS increased the phosphorylation of p70 S6 kinase, but not 4E-BP1, in a time-dependent manner, and BST204 inhibited it in a dose-dependent manner. The expression of iNOS protein, however, was partially suppressed by rapamycin, an upstream inhibitor of p70 S6 kinase. Therefore, this paper suggests that the suppression of iNOS protein by BST204 was partially correlated with the inhibition of p70 S6 kinase activation.     

High glucose enhances inducible nitric oxide synthase expression. Role of protein kinase C-betaII

The aim was to determine whether high glucose levels interfere with nitric oxide (NO) production and inducible NO synthase (iNOS) protein expression in interleukin-1beta-stimulated vascular smooth muscle cells from normotensive Wistar Kyoto and spontaneously hypertensive rats. Cells were incubated with either normal (5.5 mM) or high (22 mM) d-glucose for 72 h and with interleukin-1beta (10 ng/ml) for the last 24 h. High glucose increased nitrite levels, iNOS expression and protein kinase C activity in cells from normotensive rats and had no effect in cells from hypertensive rats. High glucose effects on nitrite production and iNOS expression was abolished by the selective inhibitor for the protein kinase C-betaII, 5,21:12,17-dimetheno-18H-dibenzo[i,o]pyrrolo[3,4-1] [1,8]diacyclohexadecine-18,20 (19H)-dione, 8-[(dimethylamino) methyl]-6,7,8,9,10,11-hexahydro-monomethanesulfonate (LY379196, 30 nM). Calphostin C (1 microM) and LY379196 (10 microM) reduced nitrite levels and iNOS expression only in cells from normotensive rats treated with both media. These results suggest that high glucose increases inducible nitric oxide synthase induction and subsequent NO production by activating the protein kinase C-betaII; this mechanism seems to be altered in hypertension.     

Role of protein kinase C in BSA-AGE-mediated inducible nitric oxide synthase expression in RAW 264.7 macrophages

In the present study, the roles of protein kinase C (PKC) in BSA-derived advanced glycosylation end products (BSA-AGEs)-induced nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression were investigated. Treatment of RAW 264.7 cells with BSA-AGEs caused dose- and time-dependent increases in NO release and iNOS expression in RAW 264.7 cells, whereas BSA alone had no effect on iNOS induction. The tyrosine kinase inhibitor (genistein), the phosphatidylinositol-specific phospholipase C inhibitor (U-73122), the phosphatidylcholine-specific phospholipase C inhibitor (D-609), and the PKC inhibitors (staurosporine, Ro 31-8220, and Go 6976) all inhibited BSA-AGE-induced NO release and iNOS expression in RAW 264.7 cells. Stimulation of RAW 264.7 cells with BSA-AGEs resulted in the formation of inositol monophosphate; the response was attenuated by U-73122 and genistein. BSA-AGEs stimulated PKC-alpha, -betaI, -delta, and -eta but not -zeta translocation from the cytosol to the membrane. However, incubation of RAW 264.7 cells with BSA-AGEs increased phosphorylation of PKC-zeta at threonine-410, which reflects activation of PKC-zeta, indicating the possible involvement of these PKC isoforms in AGE-mediated effects. Pretreatment of RAW 264.7 cells with U-73122, D-609, and genistein reduced the AGE-stimulated translocation of PKC-alpha, -betaI, -delta, and -eta and activation of PKC-zeta. Taken together, these data suggest that BSA-AGEs might activate PKC and subsequently induce iNOS expression and NO release.