雷帕霉素抑制LPS诱导的RAW264.7细胞表达和释放HMGB1的机制

目的：探讨雷帕霉素抑制LPS诱导小鼠RAW264.7细胞表达和释放HMGB1的作用机制。方法:传代培养的小鼠RAW264.7细胞分5组接种于6孔板，即仅加培养液的对照组；加250 μg/L LPS的诱导组； 诱导组基础上加100 μg/L雷帕霉素的干预组；干预组基础上加rTNF-α 50 μg/L的抗干预组；及抗干预组基础上加抗鼠TNF-α 100 μg/L的抗体中和组。培养4 h后，ELISA法检测对照组、诱导组和干预组上清液中TNF-α水平；培养24 h后，RT-PCR和Western blotting法分别检测各组细胞内HMGB1 mRNA表达水平和上清液中HMGB1含量。结果:培养4 h，干预组上清液中TNF-α水平与对照组比无显著差异（P>0.05），但明显低于诱导组（P<0.05）；培养24 h, 与对照组比，诱导组细胞内HMGB1 mRNA表达明显增强（P<0.05），上清液中HMGB1含量也明显增多（P<0.05）；干预组明显减少了HMGB1 mRNA表达及上清液中HMGB1含量（P<0.05）； 与干预组比，抗干预组细胞HMGB1 mRNA表达及上清液中HMGB1含量明显增加（P<0.05）；抗体中和组细胞HMGB1 mRNA表达水平及上清液中HMGB1含量和干预组无显著差异（P>0.05）。 结论:雷帕霉素抑制LPS诱导RAW264.7细胞表达和释放HMGB1，可能部分地与其抑制TNF-α的表达有关。     

Effect of Honghua （Flos Carthami） on nitric oxide production in RAW 264.7 cells and a.glucosidase activity

OBJECTIVE： To study the effects of extracts from Honghua （Flos Carthaml~ on lipopolysaccharide in- duced nitric oxide （NO） production in RAW 264.7 cells and the influence of the extracts on yeast a-glucosidase activity. The total flavonoid content of the extracts was also determined. METHODS： Cytotoxicity of the extracts to RAW 264.7 cells was evaluated by the ATPliteTM method. Inhibitory effects of the extracts on NO production were evaluated by Griess assay. Curcumin was used as a positive control. Screening of extracts for po- tential a-glucosidase inhibitors was done by a fiuo- rometric assay. The assay was based on the hydroly- sis of 4-methylumbelliferyl-a-D-glucopyranoside toform the fluorescent product, 4-methylumbellifer- one. Acarbose was used as a positive control. The total t3avonoid content was tested using kaempfer- ol as the standard. RESULTS： There were significant inhibitory effects on NO production when the extracts were 25-100 μg/ mL （P〈0.05） and curcumin was 2-4 μg/mL （P〈 0.001）. The extracts showed an inhibitory effect on a-glucosidase activity at the concentrations of 15.6-125 μg/mL with a half maximal （50%）inhibito- ry concentration （ICs0） of （32.8± 5.7） μg/mL, com- pared with the ICs0 of acarbose at （1.8±0.4） μg/mL. There was a significant difference between the two IC50 values （P〈0.001）. The total content of flavo- noids per gram of dried herb was 1.14 mg. CONCLUSION： Honghua （Flos Carthami） showed in- hibitory effects on NO production in activated RAW 264.7 macrophage cells and an inhibitory effect on yeast a-glucosidase. There might be a relationship between these pharmacological effects and its fla- vonoid content.     

X射线照射对RAW264·7细胞TNF-α和NF-κB表达的影响

目的探讨X射线照射诱发小鼠巨噬细胞分泌TNF-α和NF-κB的规律。方法以8Gy X射线单次照射小鼠巨噬细胞系RAW264.7细胞,并于照后不同时间收集细胞培养上清液,采用ELISA法检测RAW264.7细胞TNF-α分泌水平;以8Gy X射线单次照射小鼠巨噬细胞系RAW264.7细胞,并于照后不同时间收集细胞并进行裂解,采用Western blot实验检测NF-кB（p65）的表达。结果 X射线照射能使小鼠巨噬细胞分泌TNF-α增加,在照射后34h达到一次分泌峰值;细胞核中NF-κB（p65）分布增多,并且随着时间的延长其核移位明显增多,照射后4h达到一次最高值。结论 X射线照射能诱发小鼠巨噬细胞TNF-α和NF-κB表达增强。     

复方甘草酸苷制剂对脂多糖诱导小鼠RAW264.7细胞分泌炎症因子的调节作用

目的:研究复方甘草酸苷片剂和注射剂对脂多糖诱导小鼠巨噬细胞RAW 264.7分泌炎症因子的调节作用。方法:采用脂多糖诱导的小鼠巨噬细胞RWA264.7,建立体外炎症模型。取复方甘草酸苷片剂和注射剂,制备供试药液。分别通过,MTT、Griess和双抗体夹心ABC-ELISA等实验,测定在不同浓度的供试药液作用下RAW264.7细胞活力以及经脂多糖诱导后的RAW264.7细胞的一氧化氮、肿瘤坏死因子TNF-α及白介素IL-1β、-6和-10等炎症因子分泌量的变化。结果:复方甘草酸苷的2种制剂药液在0～300μmol.L-1浓度范围内对RAW264.7细胞活力无影响。复方甘草酸苷注射剂药液在75、150和300μmol.L-1浓度下对经脂多糖处理的RAW264.7细胞的一氧化氮分泌抑制率分别为13.8%、40.4%和53.8%,并致细胞的TNF-α分泌量降低29.8%、41.5%和52.1%,IL-1β分泌量降低39.5%、55.6%和69.6%,IL-6分泌量降低18.3%、29.5%和39.1%,但IL-10分泌量却提高了8.2%、23.8%和30.8%;而复方甘草酸苷片药液在相同浓度下对同样细胞的一氧化氮分泌抑制率分别为9.8%、27.1%和37.8%,致细胞的TNF-α分泌量降低16.6%、37.0%和48.4%,IL-1β分泌量降低28.1%、47.9%和57.9%,IL-6分泌量降低13.5%、19.9%和28.2%,IL-10分泌量提高了3.9%、14.8%和23.4%。复方甘草酸苷的2种制剂对细胞分泌炎症因子的调节作用与阳性对照药地塞米松相似,其中注射剂的作用强于片剂。结论:复方甘草酸苷可剂量依赖性地显著抑制脂多糖诱导小鼠RAW 264.7细胞产生促炎因子一氧化氮、TNF-α及IL-1β和-6并促进抗炎因子IL-10的表达,这可能为其抗炎作用机制。     

壮药赪桐乙酸乙酯部位及流份对LPS诱导的RAW264.7细胞的抗炎作用

目的 筛选赪桐乙酸乙酯部位及不同洗脱梯度二氯甲烷-甲醇部位对炎症反应的抑制作用最强的流份。 方法 使用MTT法确定壮药赪桐乙酸乙酯部位及不同洗脱梯度二氯甲烷-甲醇部位对RAW264.7细胞安全给药浓度范围,通过ELISA法测定赪桐乙酸乙酯部位及不同洗脱梯度二氯甲烷-甲醇部位对LPS诱导RAW264.7细胞分泌NO、TNF-ａ、IL-12、IL-6、IL-1β含量,筛选对炎症反应的抑制作用最强的流份。 结果 赪桐乙酸乙酯部位及流份在0.06~2.0 mg/ml浓度范围内,赪桐乙酸乙酯部位及流份对细胞活力的抑制作用逐渐增强,浓度在0.5 mg/ml以上具有明显的细胞毒性,在0.5 mg/ml以下对细胞活力具有增强作用。二氯甲烷-甲醇洗脱部位高剂量能抑制炎症因子IL-12、IL-6、TNF-ａ、IL-1β释放,对NO的分泌没有抑制作用。 结论 赪桐乙酸乙酯部位及不同洗脱梯度的二氯甲烷-甲醇部位抗炎机制是通过抑制NO、TNF-ａ、IL-12、IL-6、IL-1β炎症因子的分泌,二氯甲烷-甲醇（50:1）洗脱部位和二氯甲烷-甲醇（30:1）洗脱部位的抗炎能力较强。     

Suppressive effect of inducible nitric oxide synthase (iNOS) expression by the methanol extract of Actinodaphne lancifolia

Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) has played a crucial role in various pathophysiological processes including inflammation and carcinogenesis. Therefore, the inhibitors of NO synthesis or iNOS gene expression have been considered as potential anti-inflammatory and cancer chemopreventive agents. In our continuous search for iNOS inhibitors from natural products we have evaluated indigenous Korean plant extracts using an assay for inhibition of nitric oxide formation on lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells. As a result, the methanolic stem extract of Actinodaphne lancifolia showed an inhibitory activity of NO production in a dose-dependent manner (IC50 = 2.5 microg/ml). Additional study demonstrated that the extract of Actinodaphne lancifolia significantly suppressed the iNOS protein and gene expression in a dose-dependent manner. These results suggest that Actinodaphne lancifolia could be a potential candidate for developing an iNOS inhibitor from natural products. Further elucidation of active principles for development of new cancer chemopreventive and/or anti-inflammatory agents could be warranted.     

荆三棱顺式茋类化合物的结构修饰及抗炎活性

 目的 对荆三棱顺式茋类化合物进行结构修饰及体外抗炎活性评价。方法 分别运用甲基化、乙酰化、去甲基化反应对荆三棱中新的顺式茋类化合物sciryagarol I(1)进行结构修饰。采用噻唑蓝(MTT)法考察化合物1及其结构修饰物3~5和荆三棱中另一新顺式茋类化合物sciryagarol II(2)对RAW264.7细胞活力的影响。以脂多糖(LPS)与Pam3csk4分别诱导RAW264.7细胞炎症模型,运用酶联免疫吸附法(ELISA )法检测化合物1~5对细胞释放炎性因子肿瘤坏死因子-ɑ与白细胞介素-6(IL-6)的影响。结果 通过¹H-NMR和HRESI-MS确定修饰物3~5的结构;化合物1,2 和5能显著抑制由LPS或Pam3csk4诱导的RAW264.7细胞释放的炎性因子肿瘤坏死因子-ɑ和白细胞介素-6。结论 修饰物3~5皆为新化合物,顺式茋类化合物的抗炎作用强度与其结构上的酚羟基数目有一定关系。     

柚皮苷对破骨细胞分化的影响

目的: 探讨骨碎补单体成分柚皮苷对小鼠单核细胞RAW264.7诱导分化为破骨细胞的影响. 方法: 通过100 μg·L^-1核因子κB受体活化因子配基(RANKL)诱导RAW264.7细胞株分化为成熟破骨细胞,经TRAP特异性染色和骨吸收陷窝对破骨细胞进行鉴定.采用MTT法筛选抑制破骨细胞最强的浓度.在诱导过程中,采用筛选后含柚皮苷的培养基,诱导5 d后,通过TRAP阳性细胞计数和骨吸收面积分析来观察柚皮苷对破骨细胞的形成和骨吸收功能情况;流式细胞术检测柚皮苷对破骨细胞增殖的影响,RT-PCR检测柚皮苷对破骨细胞分化过程中核因子κB 受体活化因子(RANK)、抗酒石酸酸性磷酸酶(TRAP)、基质金属蛋白酶 9(MMP-9)、活化T细胞核因子1(NFATc1)与C-fos mRNA表达的影响. 结果: 采用100 μg·L^-1的RANKL可成功诱导成熟的、有功能的破骨细胞.柚皮苷可以抑制破骨细胞的分化和骨吸收功能;抑制破骨细胞的增殖活性;柚皮苷可明显下调破骨细胞分化过程中的RANK,TRAP,MMP-9,NFATc1 mRNA的表达,上调C-fos mRNA表达. 结论: 柚皮苷可抑制破骨细胞分化、增殖和骨吸收功能,其机制可能是通过抑制破骨细胞分化过程中特异性基因表达实现的.     

NOD8对LPS诱导巨噬细胞释放NO、TNF-α和IL-1β的影响

 目的： 探讨NOD8对脂多糖（LPS）诱导巨噬细胞释放一氧化氮（NO）、肿瘤坏死因子α（TNF-α）和白细胞介素1β（IL-1β）的影响。方法： pEGFP-C2及pEGFP-NOD8重组质粒分别转染小鼠巨噬细胞RAW264.7,以LPS刺激RAW264.7细胞0、6、12、24 h后,采用Griess reagent法测定观察细胞分泌的NO水平;ELISA法检测IL-1β 和 TNF-α 的含量;荧光法测定活化的caspase-1水平; Western blotting检测NOD8蛋白表达及NF-κB  p65亚基的核转位情况。结果： (1)与转染pEGFP-C2空质粒组比较,转染pEGFP-NOD8质粒组NOD8蛋白表达明显增加。(2) LPS刺激6、12、24 h后,RAW264.7细胞释放NO、IL-1β及TNF-α均明显增加;而在pEGFP-NOD8+LPS组RAW264.7细胞, NO于12、24 h 的释放显著降低,IL-1β于6、12、24 h的释放也明显降低,TNF-α的释放则无明显变化。（3）在LPS刺激6、12、24 h后, RAW264.7细胞caspase-1活化水平均明显升高,胞浆NF-κB p65亚基表达明显减少,表明p65核转位增加;而pEGFP-NOD8+LPS组可显著抑制caspase-1的活化以及NF-κB p65亚基的核转位,差异有统计学意义。结论： NOD8可抑制LPS诱导的巨噬细胞NO与IL-1β释放,其作用机制可能与NOD8抑制caspase-1及NF-κB 的活化有关。     

The Effect of l‐Arginine on Porphyromonas gingivalis‐Induced Phagocytosis of a Murine Macrophage‐like Raw 264.7 Cell Line

The aim of this study was to determine the effect of l‐arginine on Porphyromonas gingivalis‐induced phagocytosis by RAW 264.7 cells. The cells were pretreated with l‐arginine or d‐arginine prior to incubation with either unopsonized or opsonized P. gingivalis. In other experiments, the cells were pretreated with l‐arginine and various concentrations of NMLA (N^G‐monomethyl‐l‐arginine) prior to incubation with the bacteria. The phagocytosis was microscopically assessed and determined by the phagocytic index. The results showed that l‐arginine, but not d‐arginine enhances the ability of RAW264.7 cells to engulf the bacteria. The upregulatory effect of l‐arginine on P. gingivalis‐induced phagocytosis was abolished by NMLA. The results of the present study suggest that l‐arginine may upregulate the P. gingivalis‐induced phagocytic activity of RAW264.7 cells, perhaps, via modulation of nitric oxide synthase.