牙龈卟啉单胞菌脂多糖(Pg-LPS)对破骨细胞EphA2基因表达的调控

目的:研究小鼠单核巨噬细胞系RAW264.7在破骨分化过程中,Pg-LPS对破骨细胞EphA2表达的影响。方法:用终浓度10 mg/L的Pg-LPS 刺激RAW264.7 细胞后,分别在1、3、5 d,应用RT-PCR检测破骨细胞中EphA2基因和破骨细胞相关基因(破骨细胞内基质金属蛋白酶( MMP9)、ACP5、c-fos、组织蛋白酶K(CtsK)、NFATc1)的表达,并且通过酒石酸抗酸性磷酸酶(TRAP)染色观察实验组和对照组破骨细胞的分化成熟情况。结果:RT-PCR检测10 mg/L的Pg-LPS在第3天和5天,实验组比对照组EphA2基因表达分别增高2.4倍和1.2倍,两组之间存在显著差异(P<0.01);同时也能够促进破骨相关基因c-fos、NFATc1、CtsK、ACP5、MMP9的表达,实验组与对照组相比差异有显著性;TRAP染色结果显示:实验组比对照组的TRAP阳性多核细胞数目明显增多。结论:10 mg/L的Pg-LPS对小鼠单核巨噬细胞系RAW264.7,在破骨分化的中期和晚期均能够促进EphA2基因的表达,但是在破骨分化早期对EphA2基因的表达无明显作用。     

脂多糖刺激单核细胞上清对成骨细胞Runx2/Cbfα1表达影响

目的　观察牙龈卟啉菌脂多糖(Pg-LPS)刺激的小鼠单核巨噬细胞RAW264.7培养上清对成骨细胞Runx2/Cbfα1表达的影响。 方法　收集经100 ng/ml Pg-LPS刺激的单核巨噬细胞RAW264.7培养24 h后上清,以20%的稀释浓度的分别作用于MC3T3-E1细胞1、6、12、24、48、72 h后,采用半定量RT-PCR与Western-Blot检测细胞Runx2/Cbfα1在基因与蛋白水平上的差异性表达。 结果　成骨细胞MC3T3-E1在20%稀释浓度的培养上清刺激后,半定量RT-PCR法发现Runx2/Cbfα1基因表达显著受抑制,且呈时间依赖性,72 h降到最低; Western-Blot检测显示细胞Runx2/Cbfαa1蛋白表达6 h后开始下降,72 h降至最低。 结论　Pg-LPS刺激的小鼠单核巨噬细胞RAW264.7培养上清能抑制小鼠成骨细胞Runx2/Cbfα1的表达且与时间呈一定相关。     

硒代蛋氨酸通过NF-κB和MAPK通路抑制P.g-LPS诱导的RAW264.7细胞iNOS和COX-2表达

目的:探讨硒代蛋氨酸(Selenomethionine, SeMet)对牙龈卟啉单胞菌脂多糖(Porphyromonas gingivalis lipopolysaccharide,P.g-LPS)诱导的RAW264.7细胞的作用和机制。方法:使用P.g-LPS诱导小鼠巨噬细胞RAW264.7体外构建炎症细胞模型,CCK-8法检测不同浓度SeMet对RAW264.7细胞活性的影响。以不同浓度的SeMet(10、25、50μmol/L)干预细胞1 h后,再使用P.g-LPS诱导细胞24 h。RT-PCR法检测诱导型一氧化氮合酶(inducible nitric oxide synthase, iNOS)和环氧合酶2(cyclooxygenase-2,COX-2)相关基因表达,ELISA法检测iNOS和COX-2相关蛋白分泌情况。Western blot检测NF-κB和MAPK信号通路相关蛋白表达情况。结果:浓度低于50μmol/L的SeMet对RAW264.7细胞活性没有显著影响。对RAW264.7使用SeMet预处理后,SeMet明显抑制P.g-LPS诱导的iNOS和COX-2相关基因...     

脂多糖刺激的单核巨噬细胞培养上清液对小鼠MC3T3-E1细胞c-fos表达的影响

目的：研究经牙龈卟啉单胞菌（Porphyromonas gingivalis,P.g）脂多糖（LPS）刺激的小鼠单核巨噬细胞RAW264.7培养上清对小鼠成骨细胞（MC3T3-E1细胞）c-fos表达的影响。方法：收集100μg/L的Pg LPS刺激RAW264.724h后的上清液,以20%稀释浓度分别作用于MC3T3-E1,分别在1、3、6、12、24、48、72h时,采用RT-PCR和Western blot检测ALP mRNA、c-fos mRNA及蛋白表达水平的变化。结果：Pg LPS刺激RAW264.7细胞培养上清作用于MC3T3-E1后,ALP mRNA表达均下降,在6h时表达最低,而c-fos的mRNA和蛋白水平均提高,分别在3h和6h时达最高水平。结论：Pg LPS刺激的小鼠单核巨噬细胞RAW264.7培养上清可通过上调成骨细胞c-fos的表达而抑制其成骨能力。     

DHA对牙龈卟啉单胞菌脂多糖诱导巨噬细胞炎症的抑制作用

目的 探讨二十二碳六烯酸（DHA）对牙龈卟啉单胞菌（P.g）脂多糖（LPS）诱导巨噬细胞炎症的抑制作用。方法 用CCK-8方法检测DHA对P.g-LPS诱导的小鼠单核／巨噬细胞系RAW264.7细胞的毒性。将P.g-LPS与RAW264.7细胞共培养24 h后,更换含有DHA的培养基培养24 h,实时荧光逆转录定量PCR（qRT-PCR）检测RAW264.7细胞中肿瘤坏死因子-α（TNF-α）、白介素-1β（IL-1β）和白介素-6（IL-6）mRNA的表达。酶联免疫吸附实验检测细胞上清液中TNF-α、IL-1β、IL-6的分泌。用DCFH-DA方法检测RAW264.7细胞内活性氧（reactive oxygen species,ROS）的产生。结果 1 mg/L的P.g LPS对巨噬细胞无毒性作用（P＞0.05）,浓度≥100 μmol/L的DHA对P.g-LPS诱导的RAW264.7细胞有明显毒性作用（P＜0.05）;P.g-LPS组TNF-α、IL-1β、IL-6 mRNA表达显著高于阴性对照组（P＜0.05）;25、50、75 μmol/L的DHA减少TNF-α、IL-1β、IL-6 mRNA的表达和TNF-α、IL-6的合成（P＜0.05）;P.g-LPS组ROS产生增多,25、50、75 μmol/L的DHA减少ROS的产生（P＜0.05）,抑制程度呈浓度依赖性。结论 DHA能够有效抑制P.g-LPS诱发的巨噬细胞炎症反应。     

IL-17联合IFN-γ体外诱导RAW264.7细胞增殖和凋亡的影响

目的研究白细胞介素-17(IL-17)联合干扰素-γ(IFN-γ)在小鼠破骨前体细胞系RAW264.7分化为成熟破骨细胞过程中,对细胞增殖和凋亡的影响。方法将核因子κB受体活化因子配体(RANKL)和巨噬细胞集落刺激因子(M-CSF)诱导小鼠破骨前体细胞系RAW264.7建立破骨细胞体外诱导分化研究模型,被诱导的RAW264.7细胞培养24 h后,分为IL-17组、IFN-γ组、IL-17+IFN-γ联合组(IL-17+IFN-γ等量组、IL-17固定+IFN-γ梯度组)进行干预。抗酒石酸酸性磷酸酶(TRAP)染色对破骨细胞成熟进行鉴定,利用CCK-8细胞增殖试验检测各组细胞增殖情况,AnnexinⅤ细胞凋亡实验评价各组细胞凋亡的差异,实时荧光定量PCR检测凋亡相关基因mRNA表达差异。结果 50 ng/m L IL-17与不同浓度的IFN-γ联合,随着IFN-γ浓度升高,IL-17对RAW264.7细胞生长抑制呈浓度依赖性。IL-17和IFN-γ的联合作用比单独应用IL-17,凋亡率更高;与单独应用IFN-γ相比,凋亡相关基因Fas L表达明显增加。结论试在RAW264.7细胞向破骨细胞的分化过程中,IL-17和IFN-γ联合能抑制破骨前体RAW264.7细胞向破骨细胞的增殖,并促进RAW264.7细胞的凋亡。     

不同骨内植入材料对巨噬细胞活性的影响

目的：研究不同骨植入材料对小鼠单核巨噬细胞RAW264.7活性的影响。方法：在钛（Ti）、医用不锈钢（SS）和聚甲基丙烯酸甲酯（PMMA）材料表面及细胞培养板（PSC）上培养小鼠巨噬细胞系RAW264.7,在不同时间用cck-8法测定细胞增殖情况,实时荧光定量PCR法测定单核细胞趋化蛋白-1（MCP-1）、转化生长因子-β1（TGF-β1）和肿瘤坏死因子-α（TNF-α）mRNA表达水平。结果：小鼠巨噬细胞系RAW264.7在各种材料上均能良好生长,无明显细胞毒性。Ti和PSC组细胞增殖速率明显高于SS和PMMA组。各组材料表面巨噬细胞MCP-1mRNA表达随时间减少,PMMA组表达较高。除钛组外,其余各组巨噬细胞TGF-β1mRNA表达水平随时间增加,12h和24h时钛组表达较高。TNF-αmRNA的表达水平随时间增加,Ti组和PSC组显著高于SS和PMMA组。结论：骨内植入材料表面的巨噬细胞增殖活性和基因表达受不同材料和接触时间的影响。     

白细胞介素-24通过Jak-Stat通路对破骨细胞影响的实验研究

目的:研究白细胞介素-24(interleukin-24,IL-24)在体外通过Jak-Stat信号通路对单核巨噬细胞向破骨细胞分化的影响。方法:使用增强型绿色荧光蛋白(EGFP)确定最佳感染复数(MOI);使用ELISA检测培养基中IL-24的含量;采用Real-time PCR方法检测RAW264.7细胞中Jak-Stat信号通路相关基因Jak1、Jak2、Jak3、Stat1、Stat2、Stat3及其向破骨细胞分化过程中相关基因NFATc1、CTSK、MMP9 mRNA的表达。结果:MOI=600为最佳转染效率;转染组IL-24含量显著高于未转染组(P＜0.01);在RANKL诱导条件下转染IL-24的RAW264.7细胞与未转染组相比Jak2、Stat3 mRNA的表达增加(P＜0.05),在RANKL诱导条件下转染IL-24的RAW264.7细胞加入信号通路抑制剂后与未加入抑制剂组相比,向破骨细胞分化过程中相关基因NFATc1、CTSK、MMP9 mRNA的表达降低(P＜0.05)。结论:IL-24通过Jak-Stat信号通路调控破骨细胞的分化及功能。     

LPS刺激单核巨噬细胞培养上清对成骨细胞OPG/RANKL的影响

目的观察经牙龈卟啉单胞菌脂多糖(Pg-LPS)刺激的小鼠单核巨噬细胞RAW264.7培养上清对小鼠成骨细胞MC3T3-E1 OPG/RANKL表达的影响。方法收集经100 ng/mL Pg-LPS刺激的单核巨噬细胞RAW264.7培养24 h后的上清,以不同稀释浓度（10%、20%、30%、40%和50%）的培养上清作用于MC3T3-E1 24h,分别通过RT-PCR、免疫印迹法(Western blotting)检测细胞OPG/RANKL基因和蛋白水平表达的变化,采用SPSS17.0软件包对数据进行单因素方差分析。结果MC3T3-E1经不同稀释浓度的培养上清刺激后,其OPGmRNA及蛋白表达随浓度的增加而显著减少(P<0.05),而RANKLmRNA及蛋白表达随浓度的增加显著增加(P<0.05)。结论Pg-LPS刺激的小鼠单核巨噬细胞RAW264.7培养上清可通过抑制成骨细胞OPGmRNA及蛋白的表达,增加RANKLmRNA及蛋白的表达而抑制其成骨能力,且与浓度呈一定的正相关。     

他米巴罗汀对牙龈卟啉单胞菌抗原刺激RAW264.7细胞的影响

目的 探讨他米巴罗汀（Tamibarotene,Am80）对经牙龈卟啉单胞菌（Porphyromonas gingivalis,P.gingivalis）抗原刺激后的小鼠单核巨噬细胞RAW264.7的影响。方法 采用P.gingivalis抗原刺激RAW264.7细胞,分别用不同浓度的Am80进行干预;相差显微镜下观察各组细胞生长情况;MTS法检测不同浓度Am80对抗原刺激RAW264.7细胞的增殖情况;酶联免疫吸附法（ELISA）检测细胞培养上清中抗炎因子IL-10的含量。结果 10 nmol/L Am80能够显著抑制P.gingivalis抗原刺激RAW264.7细胞的增殖分化（P<0.001）;Am80（10 nmol/L）致抗原刺激的细胞IL-10的分泌量显著增加（P<0.05）;倒置相差显微镜下观察显示Am80抑制抗原刺激细胞的增殖分化。结论 Am80（10 nmol/L）时可显著促进P.gingivalis抗原诱导小鼠巨噬细胞分泌抗炎因子IL-10,并可能由此抑制P.gingivalis抗原诱导的炎症反应。     

Tumor necrosis factor-α and interleukin-1β expression pathway induced by Streptococcus mutans in macrophage cell line RAW 264.7

Streptococcus mutans, a major etiological agent of dental caries, frequently causes systemic disease, such as subacute bacterial endocarditis, if it enters the bloodstream. In this study, the production pathways of the proinflammatory cytokines, tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), induced by S. mutans in mouse macrophage were examined using a quantitative real-time polymerase chain reaction and an enzyme-linked immunosorbent assay. The S. mutans stimulated the expression of TNF-α and IL-1β mRNA at a multiplicity of infection of 1 : 100, which increased at 2 and 4 h, respectively, to 24 h. It also induced the production of high levels of the TNF-α and IL-1β proteins, which increased at 2 h and reached a peak at 4 and 24 h, respectively. Nuclear factor-κB (NF-κB) was activated and reached a maximum level 30 min after the S. mutans treatment. The expression of TNF-α and IL-1β mRNA and protein was suppressed by the treatment with pyrrolidine dithiocarbamate, an NF-κB inhibitor. The S. mutans-induced TNF-α expression was suppressed by the presence of SB203580, a p38 mitogen-activated protein (MAP) kinase inhibitor, or SP600125, a Jun N-terminal kinase (JNK) MAP kinase inhibitor. On the other hand, IL-1β expression was inhibited by extracellular signal-regulated kinase (ERK)/p38/JNK MAP kinase inhibitor pretreatment. In addition, TNF-α production was suppressed more in the Toll-like receptor 2(-/-) (TLR2(-/-)) macrophages than in the TLR4(-/-) macrophages, whereas IL-1β production was suppressed more in the TLR4(-/-) macrophages than in the TLR2(-/-) macrophages. These results show that S. mutans stimulates the production of TNF-α and IL-1β in the mouse macrophage cell line, RAW 264.7, by activating ERK/p38/JNK, and NF-κB through TLR2 and TLR4, respectively.     

Arginase activity in a murine macrophage cell line (RAW264.7) stimulated with lipopolysaccharide from Actinobacillus actinomycetemcomitans

AIMS: The aim of the present study was to determine whether or not lipopolysaccharide from Actinobacillus actinomycetemcomitans could stimulate arginase activity in a murine macrophage cell line (RAW264.7 cells). METHODS: RAW264.7 cells were treated with A. actinomycetemcomitans-lipopolysaccharide or lipopolysaccharide from Escherichia coli for 24 h. The effect of polymyxin B, l-norvaline, dl-norvaline, dexamethasone and cytokines (interferon-gamma and interleukin-4) on arginase activity in A. actinomycetemcomitans-lipopolysaccharide-stimulated cells was also determined. The cells were pretreated with anti-CD14, anti -toll-like receptor 2, or anti-toll-like receptor 4 antibody prior to stimulation with A. actinomycetemcomitans-lipopolysaccharide. Arginase activity was determined by a colorimetric assay. RESULTS: A. actinomycetemcomitans-lipopolysaccharide stimulated arginase activity in RAW264.7 cells in a dose-dependent manner, but was less potent than E. coli-lipopolysaccharide. Polymyxin B and l-norvaline, but not dl-norvaline, blocked the arginase activity in A. actinomycetemcomitans-lipopolysaccharide-stimulated cells. Dexamethasone and interleukin-4 but not interferon-gamma augmented arginase activity in A. actinomycetemcomitans-lipopolysaccharide-stimulated cells. Treatment of the cells with anti-CD14 and anti-toll-like receptor 4 but not anti-toll-like receptor 2 antibody decreased arginase activity in A. actinomycetemcomitans-lipopolysaccharide-stimulated cells. CONCLUSION: The results of the present study suggest that lipopolysaccharide from A. actinomycetemcomitans via CD14/toll-like receptor 4 complex molecules and the regulatory control of glucocorticoid and cytokines may stimulate arginase activity in RAW264.7 cells.     

L-arginine-dependent nitric oxide production of a murine macrophage-like RAW 264.7 cell line stimulated with Porphyromonas gingivalis lipopolysaccharide

The aim of this study was to determine nitric oxide (NO) production of a murine macrophage cell line (RAW 264.7 cells) when stimulated with Porphyromonas gingivalis lipopolysaccharides (Pg-LPS). RAW 264.7 cells were incubated with i) various concentrations of Pg-LPS or Salmonella typhosa LPS (St-LPS), ii) Pg-LPS with or without L-arginine and/or NG-monomethyl-L-arginine (NMMA), an arginine analog or iii) Pg-LPS and interferon-gamma (IFN-gamma) with or without anti-IFN-gamma antibodies or interleukin-10 (IL-10). Tissue culture supernatants were assayed for NO levels after 24 h in culture. NO was not observed in tissue culture supernatants of RAW 264.7 cells following stimulation with Pg-LPS, but was observed after stimulation with St-LPS. Exogenous L-arginine restored the ability of Pg-LPS to induce NO production; however, the increase in NO levels of cells stimulated with Pg-LPS with exogenous L-arginine was abolished by NMMA. IFN-gamma induced independent NO production by Pg-LPS-stimulated macrophages and this stimulatory effect of IFN-gamma could be completely suppressed by anti-IFN-gamma antibodies and IL-10. These results suggest that Pg-LPS is able to stimulate NO production in the RAW 264.7 macrophage cell model in an L-arginine-dependent mechanism which is itself independent of the action of IFN-gamma.     

牙龈蛋白酶对M1型巨噬细胞表达抑菌细胞因子的调控作用

目的:探讨牙龈蛋白酶对M1型巨噬细胞表达抑菌细胞因子的调控作用。方法:采用sheets改良法从Pg ATCC 33277培养物上清中制备牙龈蛋白酶,应用质谱法鉴定牙龈蛋白酶,底物发色法测定酶活性,鲎试剂检测牙龈蛋白酶中LPS残留量。体外细胞模型实验评价牙龈蛋白酶对大肠杆菌脂多糖(Ec-LPS)诱导的M1型巨噬细胞表达抑菌细胞因子的影响。实验分为3组:阴性对照组、Ec-LPS组和Ec-LPS+牙龈蛋白酶组,采用qRT-PCR和ELISA法检测M1型巨噬细胞表达的抑菌细胞因子白细胞介素12(IL-12)、一氧化氮合酶(iNOS)和白细胞介素10(IL-10)在基因和蛋白水平的表达情况。结果:制备的牙龈蛋白酶为RgpA,活性20 U/L,LPS残留量<0.01EU/mL。qRT-PCR和ELISA结果显示,与阴性对照组相比,Ec-LPS组IL-12和iNOS基因和蛋白的表达水平明显升高,IL-10的表达降低,即成功诱导M1型巨噬细胞,组间有显著差异(P<0.01);Ec-LPS+牙龈蛋白酶组IL-12、iNOS和IL-10基因和蛋白的表达较Ec-LPS组显著降低,但高于阴性对照组,组间有显著差异(P<0.01)。结论:牙龈蛋白酶具有抑制M1型巨噬细胞表达抑菌细胞因子IL-12、iNOS的作用。     

重离子与X射线辐照对人舌鳞状细胞癌Tca8113细胞株CXCR4表达的影响

目的:以CXCR4mRNA的表达量为指标探讨不同辐射方式对Tca8113细胞株细胞侵袭能力的影响。方法:采用不同剂量的重离子束与X-ray对细胞进行辐射,采用荧光实时定量PCR法观察细胞中CXCR4mRNA表达量的变化。结果:与空白对照组比较,在相同辐射剂量下,X线辐照组细胞中CXCR4的表达量在8 h时较低,于12 h达到高峰,该峰值在1Gy、4Gy组较为显著(P<0.05),在2Gy组则差异不明显;而重离子辐照组细胞中CXCR4的mRNA表达水平在辐照后12 h内均明显降低(P<0.05)。两者在24 h的表达基本恢复至空白对照组水平。在相同时间点时,重离子组CXCR4的表达量与X线组比较则有显著降低(P<0.01)。结论:与常规X线相比,重离子对体外培养的人舌鳞癌细胞中CXCR4的表达的抑制能力更强,提示重离子抑制舌鳞癌细胞侵袭的能力优于常规X射线。     

Nitric oxide production by a murine macrophage cell line (RAW264.7) stimulated with lipopolysaccharide from Actinobacillus actinomycetemcomitans

The aim of this study was to determine whether Actinobacillus actinomycetemcomitans lipopolysaccharide (LPS-A. actinomycetemcomitans) could stimulate a murine macrophage cell line (RAW264.7 cells) to produce nitric oxide (NO). The cells were treated with LPS-A. actinomycetemcomitans or Escherichia coli LPS (LPS-Ec) for 24 h. The effects of N(G)-monomethyl-L-arginine (NMMA), polymyxin B and cytokines (IFN-gamma, TNF-alpha, IL-4 and IL-12) on the production of NO were also determined. The role of protein tyrosine kinase, protein kinase C and microtubulin organization on NO production were assessed by incubating RAW264.7 cells with genistein, bisindolylmaleide and colchicine prior to LPS-A. actinomycetemcomitans stimulation, respectively. NO levels from the culture supernatants were determined by the Griess reaction. The results showed that LPS-A. actinomycetemcomitans stimulated NO production by RAW264.7 cells in a dose-dependent manner, but was slightly less potent than LPS-Ec. NMMA and polymyxin B blocked the production of NO. IFN-gamma and IL-12 potentiated but IL-4 depressed NO production by LPS-A. actinomycetemcomitans-stimulated RAW264.7 cells. TNF-alpha had no effects on NO production. Genistein and bisindolylmalemaide, but not colchicine, reduced the production of NO in a dose-dependent mechanism. The results of the present study suggest that A. actinomycetemcomitans LPS, via the activation of protein tyrosine kinase and protein kinase C and the regulatory control of cytokines, stimulates NO production by murine macrophages.     

l‐arginine‐dependent nitric oxide production of a murine macrophage‐like RAW 264.7 cell line stimulated with Porphyromonas gingivalis lipopolysaccharide

The aim of this study was to determine nitric oxide (NO) production of a murine macrophage cell line (RAW 264.7 cells) when stimulated with Porphyromonas gingivalis lipopolysaccharides (Pg‐LPS). RAW264.7 cells were incubated with i) various concentrations of Pg‐LPS or Salmonella typhosa LPS (St‐LPS), ii) Pg‐LPS with or without l ‐arginine and/or N^G‐monomethyl‐l ‐arginine (NMMA), an arginine analog or iii) Pg‐LPS and interferon‐γ (IFN‐γ) with or without anti‐IFN‐γ antibodies or interleukin‐10 (IL‐10). Tissue culture supernatants were assayed for NO levels after 24 h in culture. NO was not observed in tissue culture supernatants of RAW 264.7 cells following stimulation with Pg‐LPS, but was observed after stimulation with St‐LPS. Exogenous l ‐arginine restored the ability of Pg‐LPS to induce NO production; however, the increase in NO levels of cells stimulated with Pg‐LPS with exogenous l ‐arginine was abolished by NMMA. IFN‐γ induced independent NO production by Pg‐LPS‐stimulated macrophages and this stimulatory effect of IFN‐γ could be completely suppressed by anti‐IFN‐γ antibodies and IL‐10. These results suggest that Pg‐LPS is able to stimulate NO production in the RAW264.7 macrophage cell model in an l ‐arginine‐dependent mechanism which is itself independent of the action of IFN‐γ.