11种中药提取物对脂多糖诱导的RAW264.7细胞生成一氧化氮的影响

目的研究11味中药提取物对脂多糖(LPS)诱导巨噬细胞RAW264.7产生一氧化氮(NO)的抑制作用。方法使用MTT法测试样品对RAW264.7的细胞毒作用,Griess法测定样品对LPS刺激RAW264.7细胞产生NO的含量,N-单甲基-L-精氨酸单乙酸酯(L-NMMA)为阳性对照。结果 11味中药甲醇提取物均具有一定的抑制RAW264.7细胞生成NO的作用,其中秦艽、五加皮、独活、雷公藤、仙鹤草提取物的抑制作用最强(IC50在4.3±0.6~14.8±2.6μg·m L-1),且选择指数较高(SI>27)。结论本研究系统评价了11味常用中药提取物对LPS诱导RAW 264.7细胞产生NO的影响,研究结果进一步证实这些中药的抗炎活性。     

不同分子量枸杞多糖对RAW264.7巨噬细胞的免疫调节作用

目的:研究不同分子量枸杞多糖(lycium barbarum polysaccharides,LBP)对小鼠巨噬细胞RAW264.7的免疫调节作用.方法:本研究通过水提醇沉及柱分离法以获得不同分子量的LBP成分.运用CCK8法检测不同给药浓度的LBP对RAW 264.7细胞增殖的影响;采用中性红吞噬实验测定LBP对细胞...     

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。     

长春碱对RAW264.7细胞增殖和分泌一氧化氮的影响

目的:研究长春碱对RAW264.7细胞增殖和分泌一氧化氮(NO)的影响。方法:采用MTT法检测长春碱对细胞增殖的抑制作用;流式细胞术观察长春碱对细胞周期的阻断作用;Western blot法检测细胞中cyclin B1蛋白含量的变化;Griess试剂盒检测长春碱对脂多糖(LPS)刺激的细胞分泌NO的影响。结果:长春碱可抑制RAW264.7细胞的增殖,使细胞周期阻滞于G2～M期,呈浓度依赖性地降低细胞中cyclin B1的含量,并抑制LPS刺激的RAW264.7细胞的NO分泌(P<0.05或P<0.01)。结论:长春碱可能通过抑制RAW264.7细胞表达cyclin B1,使细胞周期停滞于G2～M期,从而抑制了RAW264.7细胞的增殖,影响RAW264.7细胞的生物学行为。     

苹果多糖的制备及对脂多糖诱导RAW 264.7细胞凋亡的影响

摘 要 目的：观察苹果多糖（AP）对脂多糖（LPS）诱导RAW 264.7细胞凋亡的影响及其机制。方法: 采用水提醇沉法从苹果果渣中提取苹果多糖,并测定其糖含量和分子量。采用流式细胞仪考察AP对LPS诱导RAW 264.7细胞凋亡的作用。采用Western Blot法考察AP对LPS诱导RAW 264.7细胞中Bcl 2、Bax蛋白表达的影响。结果: 经水提醇沉法提取纯化得到苹果多糖的糖含量为91.3%,重均分子量为184613 Da。流式细胞仪检测结果显示,LPS诱导RAW 264.7细胞凋亡明显高于正常对照组（P<0.01）;与LPS组比较,浓度为0.5 mg·mL^-1的AP作用72 h后RAW 264.7细胞凋亡率显著降低（P<0.01）,浓度为1.0 mg·mL^-1的AP作用48,72 h后RAW 264.7细胞凋亡率显著降低（P<0.01）。Western Blot检测结果显示,与正常对照组比较,LPS诱导RAW 264.7细胞中的Bcl 2蛋白在48,72 h表达明显升高,差异具有统计学意义（P<0.01）;与LPS组比较,浓度为1 mg·mL^-1的AP作用后,升高了LPS诱导的RAW 264.7细胞Bcl 2蛋白的表达,降低其Bax蛋白的表达,差异具有统计学意义（P<0.01）。结论:AP抑制LPS诱导RAW 264.7细胞凋亡,其机制可能是通过提高RAW 264.7细胞中Bcl 2蛋白的表达,降低其Bax蛋白表达。     

STAT5通路抑制剂匹莫齐特对RAW264.7细胞炎症模型NO和iNOS表达的影响

目的:研究STAT5通路抑制剂匹莫齐特对脂多糖(LPS)诱导的小鼠巨噬细胞RAW264.7炎症模型一氧化氮(NO)和一氧化氮合成酶(i NOS)表达的影响。方法:取对数生长期RAW264.7细胞,分为空白对照组、药物对照(匹莫齐特10μmol/L)组、模型(LPS 1μg/ml)组和匹莫齐特低、中、高浓度(2.5、5、10μmol/L)组,给予LPS前30 min给予匹莫齐特,继续培养24 h。采用Griess法检测各组细胞培养液上清中NO的含量;实时定量聚合酶链反应(RT-PCR)法检测i NOS m RNA表达;Western blot法检测i NOS和磷酸化STAT5(p-STAT5)的蛋白表达。结果:与空白对照组比较,模型组细胞中NO含量、i NOS m RNA和蛋白表达、p-STAT5/STAT5均增加,差异具有统计学意义(P<0.01)。与模型组比较,匹莫齐特中、高浓度组细胞中NO含量、i NOS m RNA和蛋白表达、p-STAT5/STAT5均降低,差异具有统计学意义(P<0.01或P<0.05)。结论:STAT5通路抑制剂匹莫齐特可通过抑制细胞中i NOS m RNA和蛋白的表达而抑制NO的释放。     

PI3K/PTEN/Akt/mTOR通路在浒苔多糖粗提物调节小鼠巨噬细胞RAW264.7免疫功能中的作用

目的:验证浒苔多糖粗提物上调小鼠巨噬细胞RAW264.7免疫功能,并初步探讨其是否通过PI3K/PTEN/Akt/m TOR通路实现。方法:以不同浓度浒苔多糖粗提物干预RAW264.7细胞,干预不同时间后四甲基偶氮噻唑蓝(MTT)比色法测定巨噬细胞RAW264.7增殖率;ELISA法测定白介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)水平;实时荧光定量PCR检测m TORm RNA的表达水平;以100nmol/L雷帕霉素、500μg/ml浒苔多糖粗提物、500μg/m L浒苔多糖粗提物+100nmol/L雷帕霉素干预RAW264.7细胞,测定细胞因子IL-6、TNF-α分泌水平。结果:500μg/m L浒苔多糖粗提物干预12h,可获得最佳增殖率53.47%;RAW264.7细胞分泌IL-6的水平随着浒苔多糖粗提物浓度的增大而增加,且在24h达到分泌高峰,TNF-α分泌水平随着时间延长而增加(F=311.63,P0.001),同时随着干预浓度的提高而增加(F=51.80,P0.001);浒苔多糖粗提物干预12、24h后,m TOR表达水平增高(F=4.256,P=0.029;F=20.606,P0.001);较之500μg/m L浒苔多糖粗提物组,500μg/m L浒苔粗提物+100nmol/L雷帕霉素组IL-6水平下降44.58%,TNF-α水平下降65.96%(P均0.001)。结论:浒苔多糖粗提物促进巨噬细胞RAW264.7增殖,调节其细胞因子释放,可能与PI3K/PTEN/Akt/m TOR通路有关。     

铁皮石斛多糖对RAW264.7细胞分泌TNF-α的影响

目的研究铁皮石斛多糖(polysaccharides from Den-drobium officinale,DOP)对小鼠巨噬细胞系RAW264.7细胞分泌TNF-α的影响并探讨其作用机制。方法 MTT法检测细胞活性;ELISA法检测TNF-α的分泌水平;反转录聚合酶链反应(RT-PCR)检测TNF-αmRNA表达量;Western blot技术检测胞质I-κBα蛋白的表达量。结果 DOP在20～160mg·L-1范围内明显促进RAW264.7细胞增殖,无细胞毒性;与空白对照组比较,DOP剂量依赖性地促进TNF-α的分泌;上调TNF-αmRNA表达;Western blot结果显示DOP能明显降低胞质内I-κBα蛋白水平。结论 DOP能增强RAW264.7细胞分泌TNF-α,其作用机制可能与降低胞质内I-κBα蛋白水平,活化核转录因子NF-κB,诱导TNF-αmRNA的表达有关。     

LC2W胞外多糖对大肠杆菌脂多糖诱导RAW264.7细胞因子表达的影响

<正>乳杆菌对维持肠道内微生态平衡、提高机体抗感染、抗病毒能力,发挥机体局部或全身的防御功能具有重要作用。乳杆菌的生理功能可能与其所分泌的胞外多糖(Exopolysac-charide,EPS)有密切关系[1-2]。药理研究表明,多糖能激活     

库拉索芦荟多糖对小鼠腹腔巨噬细胞一氧化氮生成的影响

目的研究库拉索芦荟多糖对小鼠腹腔巨噬细胞一氧化氮(NO)生成的影响。方法用G riess法测定巨噬细胞一氧化氮的生成量。结果库拉索芦荟多糖在25～400μg/mL浓度范围可显著促进正常巨噬细胞的NO生成,在50～400μg/mL浓度范围可抑制LPS激活的巨噬细胞的NO生成。结论库拉索芦荟多糖对小鼠腹腔巨噬细胞一氧化氮的生成具有双向调节作用。     

Inhibition of nitric oxide production in RAW 264.7 cells by azaphilones from xylariaceous fungi

The aim of this study was to discover a novel agent that suppresses nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) in RAW 264.7 cells. We carried out a screening test in fifteen azaphilone compounds, which were isolated from xylariaceous inedible mushrooms. The structure-activity relationship was discussed; accordingly, azaphilones were divided into five groups based on the functional groups attached to the main azaphilone backbone. Rubiginosin A, an azaphilone with an orsellinic acid moiety attached to the bicyclic azaphilone through an ester linkage, showed potential inhibitory activity. To clarify the mechanism involved, total RNA extraction, followed by RT-PCR for inducible nitric oxide synthase (iNOS) and finally electrophoresis on agarose gel were performed. These findings indicated that suppression of the LPS-induced NO production of rubiginosin A is due to the inhibition of iNOS protein synthesis.     

Chlorophyllin suppression of lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells

Chlorophyllin (CHL), a water-soluble derivative of chlorophyll, functions as an anticarcinogen and antioxidant. In the present study, we investigated the effect of CHL on nitric oxide production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Treatment with CHL inhibited nitric oxide production in the LPS-stimulated RAW 264. 7 cells in a dose-related manner. Competitive RT-PCR analysis, using a DNA competitor as an internal standard, demonstrated that the treatment with 1, 10, and 50 microM CHL decreased LPS-induced iNOS mRNA expression in a concentration-dependent manner. Since the expression of the iNOS gene is mainly regulated by NF-kappaB, we then examined the effects of CHL on the NF-kappaB DNA binding activity, using an electrophoretic mobility shift assay. CHL down-regulated the NF-kappaB DNA binding on its cognate recognition site at the concentrations just noted. Employing a transfection and reporter gene expression system with p(NF-kappaB)(3)-chloramphenicol acetyl transferase (CAT), the treatment of CHL produced a dose-dependent inhibition of CAT activity in RAW 264.7 cells. Furthermore, CHL partially restored LPS-decreased IkappaBalpha, an inhibitory protein against NF-kappaB activation, in the cytosolic extract from the LPS-treated cells determined by immunoblot analysis. CHL also protected the hydroxyl radical-induced cytotoxicity in RAW 264.7 cells, indicating its antioxidant effect. These results suggest that CHL suppresses the nitric oxide production and iNOS mRNA expression mediated by the inhibition of NF-kappaB activation, and its action mechanism may be based on its antioxidant effect.     

Glycoprotein isolated from Rhus verniciflua Stokes inhibits inflammation-related protein and nitric oxide production in LPS-stimulated RAW 264.7 cells

Rhus verniciflua Stokes (RVS) has traditionally been used for medical purpose, such as healing of inflammatory diseases in South Korea. Glycoprotein (36 kDa) was isolated from RVS fruit, purified and used to evaluate the inhibitory effect on inflammatory-related proteins and nitric oxide (NO) production in lipopolysaccharide (LPS, 200 ng/ml)-stimulated RAW 264.7 (murine macrophage cell line). Our results were showed that RVS glycoprotein has a strong antioxidative activity against lipid peroxyl radicals in cell-free system, and inhibits NO production in LPS-stimulated RAW 264.7 cells. To elucidate the inhibitory effect of RVS glycoprotein on activities of inflammatory-related proteins, we firstly evaluated the amount of intracellular reactive oxygen species (ROS), and expression of intracellular protein kinase C (PKC), nuclear factor (NF)-kappaB, and activator protein-1 (AP-1). The results in the present study showed that RVS glycoprotein (200 microg/ml) inhibits ROS production and PKCalpha translocation, and down-regulates the expression of NF-kappaB and AP-1. Such upstream signals consequently inhibited the levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 expression. Therefore, we speculate that RVS glycoprotein inhibits the inflammatory-related protein and can act as an anti-inflammatory agent.     

Carboxymethylation enhances the maturation-inducing activity in dendritic cells of polysaccharide from the seeds of Plantago asiatica L.

Carboxymethylation is a well-known modification process for polysaccharides. To evaluate the biological availability of carboxymethyl, polysaccharide from the seeds of Plantago asiatica L. (PLCP) was carboxymethylated (CM-PLCP) and the immunomodulatory activities of five CM-PLCPs of gradient degree of substitution (DS) from 0.40 to 0.62 were determined on dendritic cells (DCs) in vitro. Compared with DCs treated with PLCP, DCs treated with CM-PLCP of DS_0.50, DS_0.55, DS_0.62, as well as CD86 and CD80, expressed higher levels of MHCII, CD86 and CD80 surface molecules. In addition, the secretion of IL-12p70 and the mRNA of CCR7 and CXCR4 chemokines were increased, while the endocytosis activities were inhibited. Correspondingly, stronger mixed lymphocyte reactions were induced by the DCs treated with the CM-PLCPs. The results showed that carboxymethylation modification of relevant high DS can enhance the DC maturation-inducing function of PLCP, indicating the potential application of carboxymethylated polysaccharide as an immunotherapeutic adjuvant.     

Inhibition of nitric oxide production in RAW264.7 macrophages by cannabinoids and palmitoylethanolamide

We have investigated the inhibition of lipopolysaccharide stimulated nitric oxide production in RAW264.7 macrophages by the cannabinoids and the putative cannabinoid CB(2)-like receptor ligand, palmitoylethanolamide. (R)-(+)-[2, 3-dihydro-5-methyl-3-(4-morpholinylmethyl)pyrrolo-[1,2,3-de]-1, 4-benzoxazin-6-yl]-1-naphthalenylmethanone mesylate ((+)-WIN55212) and, to a lesser extent (-)-cis-3-[2-hydroxy-4-(1, 1-dimethylheptyl)phenyl]-trans-4-(3-hydroxy-propyl)cyclohexan++ +-1-ol (CP55940), significantly inhibited lipopolysaccharide stimulated nitric oxide production. The level of inhibition was found to be dependent on the concentration of lipopolysaccharide used to induce nitric oxide production. Palmitoylethanolamide significantly inhibited nitric oxide production induced by lipopolysaccharide. The inhibition of nitric oxide production by (+)-WIN55212 but not palmitoylethanolamide was significantly attenuated in the presence of the cannabinoid CB(2) receptor antagonist, N-[(1S)-endo-1,3, 3-trimethyl bicyclo [2.2.1] heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazo le- 3-carboxamide (SR144528). (+)-WIN55212 produced a pertussis toxin-sensitive parallel rightward shift in the log concentration-response curve for lipopolysaccharide, causing a fivefold increase in the EC(50) value for lipopolysaccharide with no change in the E(max) value. (-)-WIN55212 had no effect on the log concentration-response curve for lipopolysaccharide. Palmitoylethanolamide did not produce a rightward shift in the lipopolysaccharide concentration-response curve. However, it did produce a pertussis toxin-insensitive reduction in the E(max) value. The results suggest that the inhibition of lipopolysaccharide mediated nitric oxide release by (+)-WIN55212 in murine macrophages is mediated by cannabinoid CB(2) receptors. In contrast, the inhibition by palmitoylethanolamide does not appear to be mediated by cannabinoid receptors.     

Sesquiterpene lactones from Inula hupehensis inhibit nitric oxide production in RAW264.7 macrophages

Phytochemical investigation of the aerial parts of Inula hupehensis Ling. led to the isolation and identification of 27 sesquiterpene lactones (1-27), including three new eudesmanolides (3-5), three new germacranolides (9-11), one new xanthanolide (16), two new carabrone derivatives (25-26), and 18 known sesquiterpene lactones. The structures were elucidated by extensive spectroscopic methods and comparison to previously reported spectroscopic data. All compounds were evaluated for their inhibitory effects against LPS-induced nitric oxide production in RAW264.7 macrophages, and compound 5 showed the strongest activity with the IC?? value of 3.2 ± 0.4 μM.