原花青素对脂多糖诱导RAW2647细胞COX-2酶活性、mRNA及蛋白表达的影响

目的探讨原花青素对脂多糖(LPS)诱导小鼠巨噬细胞株RAW264.7细胞COX-2酶活性及蛋白表达的影响。方法放射免疫法检测COX-2酶活性，RT-PCR检测COX-2 mRNA表达，Western blotting检测COX-2蛋白表达。结果原花青素(0.8，4和20 mg·L^-1)不影响LPS诱导RAW264.7细胞COX-2酶活性，可下调LPS诱导RAW264.7细胞COX-2 mRNA表达；原花青素(4和20 mg·L^-1)下调LPS诱导RAW264.7细胞COX-2蛋白表达。结论原花青素不影响LPS诱导RAW2647细胞COX-2酶活性，但对LPS诱导RAW264.7细胞COX-2 mRNA及蛋白表达抑制作用明显。     

原花青素对RAW264.7细胞膜相关前列腺素E2合成酶-1表达的影响

目的 探讨原花青素对RAW264.7细胞膜相关前列腺素E2合成酶-1(mPGES-1)表达的影响.方法 酶免疫测定法(EIA)检测原花青素对PGE2生成的影响,逆转录聚合酶链反应(RT-PCR)检测mPGES-1mRNA的表达,Western blotting检测mPGES-1蛋白的表达.结果 脂多糖(LPS)可以促进RAW264.7细胞PGE2的生成同时上调mPGES-1mRNA和蛋白的表达,而原花青素(4、20mg·L-1)下调LPS诱导的RAW264.7细胞mPGE-1mRNA和蛋白的表达,从而抑制LPS诱导的RAW264.7细胞PGE2的生成.结论 原花青素在mRNA和蛋白水平抑制LPS诱导的RAW264.7细胞mPGES-1表达从而减少PGE2的合成,这可能是原花青素抗炎的机制之一.     

原花青素对RAW264.7细胞膜相关前列腺素E2合成酶-1表达的影响

目的探讨原花青素对RAW264.7细胞膜相关前列腺素E2合成酶-1(mPGES-1)表达的影响。方法酶免疫测定法(EIA)检测原花青素对PGE2生成的影响,逆转录聚合酶链反应(RT-PCR)检测mPGES-1mRNA的表达,Western blotting检测mPGES-1蛋白的表达。结果脂多糖(LPS)可以促进RAW264.7细胞PGE2的生成同时上调mPGES-1mRNA和蛋白的表达,而原花青素(4、20 mg.L-1)下调LPS诱导的RAW264.7细胞mPGES-1mRNA和蛋白的表达,从而抑制LPS诱导的RAW264.7细胞PGE2的生成。结论原花青素在mRNA和蛋白水平抑制LPS诱导的RAW264.7细胞mPGES-1表达从而减少PGE2的合成,这可能是原花青素抗炎的机制之一。     

八肽胆囊收缩素抑制LPS诱导的RAW264.7细胞AP-1活性及IL-6表达

目的研究八肽胆囊收缩素(CCK-8)对LPS诱导RAW264.7细胞IL-6表达的影响及相关机制。方法用ELISA及RT-PCR法检测RAW264.7细胞IL-6蛋白及mR-NA表达;用EMSA方法检测RAW264.7细胞AP-1 DNA结合活性。结果①LPS可时间依赖性的诱导RAW264.7细胞IL-6蛋白及mRNA表达;②10-10 mol.L-1 CCK-8对LPS诱导的RAW264.7细胞IL-6表达无明显影响;10-8、10-6 mol.L-1 CCK-8浓度依赖性地抑制了LPS诱导的RAW264.7细胞IL-6表达;③10-10 mol.L-1 CCK-8未影响LPS诱导的AP-1活性,10-8、10-6 mol.L-1 CCK-8浓度依赖性地抑制了LPS诱导的AP-1活性。结论 CCK-8通过抑制AP-1 DNA结合活性而抑制了LPS诱导的RAW264.7细胞IL-6表达,这可能是CCK-8发挥抗炎作用的信号转导机制之一。     

八肽胆囊收缩素通过p38MAPK通路抑制LPS诱导的RAW264.7细胞IL-1β表达

目的研究八肽胆囊收缩素(CCK-8)对LPS诱导RAW264.7细胞IL-1β表达的影响及相关机制。方法用ELISA及RT-PCR法检测RAW264.7细胞IL-1βmRNA及蛋白表达;用Western blot检测RAW264.7细胞p38 MAPK的磷酸化水平。结果①LPS可时间依赖性的诱导RAW264.7细胞IL-1βmRNA及蛋白的表达,分别于刺激后3 h及6 h达到高峰;②10-10 mol.L-1 CCK-8对LPS诱导的RAW264.7细胞IL-1β表达无影响;10-8、10-6 mol.L-1CCK-8浓度依赖性地抑制了LPS诱导的RAW264.7细胞IL-1β表达;③10-10 mol.L-1 CCK-8未影响LPS诱导的p-p38MAPK水平,10-8、10-6 mol.L-1 CCK-8浓度依赖性地抑制了LPS诱导的p-p38 MAPK水平;④p38 MAPK特异性抑制剂SB203580可抑制LPS诱导的RAW264.7细胞IL-1β表达,与CCK-8共同作用后,抑制作用进一步加强。结论 CCK-8通过抑制p38 MAPK磷酸化而抑制了LPS诱导的RAW264.7细胞IL-1β表达,这可能是CCK-8发挥抗炎作用的信号转导机制之一。     

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。     

PI3K信号通路在LPS诱导RAW264.7细胞表达sTREM-1中的作用

目的：探讨磷脂酰肌醇3-激酶(PI3K)信号通路在脂多糖(LPS)诱导RAW264.7细胞表达可溶性髓样细胞触发受体-1(sTREM-1)中的作用。方法培养小鼠巨噬细胞株RAW264.7,采用相同浓度的LPS在不同时间诱导RAW264.7细胞,应用Western blot法分别检测PI3K蛋白表达水平,RT-PCR法检测PI3K mRNA表达水平,酶联免疫吸附(ELISA)法检测细胞培养血清中sTREM-1表达水平。用不同浓度PI3K特异性抑制剂LY294002处理细胞,观察上述指标变化。结果 LPS可时间依赖性地诱导RAW264.7细胞PI3K蛋白、PI3K mRNA的表达;LY294002可浓度依赖性地抑制PI3K蛋白、PI3K mRNA的表达;LY294002阻断PI3K信号转导通路后,LPS对sTREM-1表达的诱导作用受到显著抑制,并且具有剂量依赖性。结论 LPS通过PI3K信号通路诱导RAW264.7细胞表达sTREM-1。     

非诺贝特抑制血管紧张素Ⅱ所诱导的心脏成纤维细胞骨桥蛋白表达升高

目的：探讨过氧化物酶体增殖物激活受体α（PPARα）激动剂非诺贝特对血管紧张素Ⅱ（An-gⅡ）诱导的心脏成纤维细胞骨桥蛋白表达升高的影响。方法：分离并传代培养SD大鼠乳鼠心脏成纤维细胞,使用不同浓度（0、25、50、100μmol/L）的非诺贝特预处理1h后,加入An-gⅡ作用24h。分别采用实时定量PCR法和Western blotting技术检测骨桥蛋白mRNA和蛋白表达情况。结果：非诺贝特显著抑制AngII诱导的心脏成纤维细胞骨桥蛋白mRNA及蛋白的表达,并且呈剂量依赖性。结论：非诺贝特对心脏成纤维细胞中骨桥蛋白的表达具有明显的抑制作用,这可能是其在心血管系统发挥抗纤维化和抗炎作用的部分机制。     

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。     

非诺贝特对溶血卵磷脂诱导的血管内皮细胞增生及凋亡的影响

目的:观察非诺贝特对溶血卵磷脂(LPC)诱导的血管内皮细胞增生、凋亡的影响并探讨其机制。方法:体外培养人脐静脉内皮细胞(HUVECs),分为正常对照组、LPC组、非诺贝特低浓度组(10μmol·L-1)、非诺贝特中浓度组(50μmol·L-1)及非诺贝特高浓度组(100μmol·L-1)。分别观测LPC对血管内皮细胞增生、凋亡及凋亡调控蛋白抑制X连锁凋亡抑制蛋白(XIAP)的影响,及非诺贝特干预后的变化。结果:与正常对照组比较,LPC抑制内皮细胞增生,促进内皮细胞凋亡,XIAP表达减弱。非诺贝特可干预LPC对内皮细胞的作用,使内皮细胞增生增强,凋亡减少,XIAP表达增强。结论:非诺贝特可通过促进XIAP表达干预LPC对HUVECs增生及凋亡的影响。     

PPARα activator fenofibrate modulates angiotensin II-induced inflammatory responses in vascular smooth muscle cells via the TLR4-dependent signaling pathway

Angiotensin II (Ang II) is a crucial contributor to inflammatory processes involved in development and progression of atherosclerotic lesion. Toll-like receptor 4 (TLR4) signaling responsible for the initiation of inflammation also participates in pathogenesis of atherosclerosis. The protective effect of peroxisome proliferator-activated receptor α (PPARα) activators on atherosclerosis may be due to their impact on vascular inflammation, plaque instability and thrombosis. However, mechanisms underlying the inhibitory effects of PPARα activators on Ang II-induced vascular inflammation and the TLR4-dependent signaling pathway involved in vascular smooth muscle cells (VSMCs) remain unclear. The present study demonstrated that PPARα activator fenofibrate decreased Ang II-induced generation of pro-inflammatory mediators such as TLR4, MMP-9 and TNF-α, but enhanced production of anti-inflammatory molecules like PPARα and 6-keto-PGF_1α both in vivo and in vitro. Meanwhile, treatment of VSMCs with the TLR4 inhibitor or TLR4 siRNA showed that the inhibitory effects of fenofibrate on Ang II-induced inflammatory responses in VSMCs were dependent on TLR4. Furthermore, fenofibrate depressed Ang II-induced inflammatory responses in VSMCs by intervening the downstream effector molecules of the TLR4-dependent signaling pathway, including interferon-gamma inducible protein 10 (IP-10), protein kinases C (PKC) and nuclear factor κB (NF-κB). Thus, these findings provide the evidence for beneficial effects of PPARα activator fenofibrate to counter-regulate vascular inflammation induced by Ang II. More importantly, anti-inflammatory action of fenofibrate via interfering with the TLR4-dependent signaling pathway (TLR4/IP-10/PKC/NF-κB) works in concert to protect against atherosclerosis.     

Isotrifoliol inhibits pro-inflammatory mediators by suppression of TLR/NF-κB and TLR/MAPK signaling in LPS-induced RAW264.7 cells

Soybeans, produced by Glycine max (L.) Merr., contain high levels of isoflavones, such as genistein and daidzein. However, soy leaves contain more diverse and abundant flavonol glycosides and coumestans, as compared to the soybean. This study investigated the anti-inflammatory effects of the major coumestans present in soy leaf (coumestrol, isotrifoliol, and phaseol) in lipopolysaccharide (LPS)-induced RAW264.7 cells. Coumestans significantly reduced LPS-induced nitric oxide (NO), prostaglandin E2 (PGE₂), and reactive oxygen species (ROS) production; isotrifoliol had the most potent anti-inflammatory activity. Isotrifoliol reduced LPS-mediated induction of mRNA expression of inducible nitric-oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-1β, IL-6, tumor necrosis factor alpha (TNFα), and chemokines, such as chemokine (C-C motif) ligand (CCL) 2, CCL3, and CCL4. Isotrifoliol prevented NF-κB p65 subunit activation by reducing the phosphorylation and degradation of the inhibitor of NF-κB. And isotrifoliol significantly suppressed phosphorylation of the extracellular signal-regulated protein kinase 1/2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK). Furthermore, isotrifoliol suppressed LPS-induced Toll-like Receptor (TLR) signaling pathway, including mRNA expression of TNF receptor associated factor 6, transforming growth factor beta-activated kinase 1 (TAK1), TAK1 binding protein 2 (TAB2), and TAB3. These results demonstrate that isotrifoliol exerts an anti-inflammatory effect by suppressing the expression of inflammatory mediators via inhibition of TLR/NF-κB and TLR/MAPK signaling in LPS-induced RAW264.7 macrophages. Therefore, isotrifoliol can be used as an anti-inflammatory agent, and coumestan-rich soy leaf extracts may provide a useful dietary supplement.     

Triptolide suppresses lipopolysaccharide-induced activity of toll-like receptor 4 in mouse macrophage cell line RAW 264.7

Toll-like receptor 4 (TLR4) has attracted a great deal of attention in ischemia–reperfusion injury in recent years. Triptolide has potent anti-inflammatory and immunosuppressive effects; however, the mechanism has not been fully delineated. The objective of this study was to evaluate the effects of triptolide on TLR4 expression in the mouse macrophage cell line RAW 264.7. In the first part of this study, the mouse macrophage cell line RAW 264.7 was treated with different concentrations of lipopolysaccharide (LPS) for 6?h to find the concentration of LPS to be used in the second part of this study. In the second part of the study, mouse macrophage cell line RAW 264.7 was pre-treated with triptolide at different concentrations for 1?h, and then exposed to LPS. The expression of the TLR4 and HSP70 mRNA and protein, as well as the levels of tumour necrosis factor (TNF)-α and interleukin (IL)-6, were assessed. In the first part of this study, the expression level of TLR4 mRNA was increased significantly in the macrophage cell line treated with LPS, and reached a plateau at 100?ng/ml. In the second part of this study, the mouse macrophage cell line RAW 264.7 pre-treated with different concentrations of triptolide, showed a dose-dependent inhibition of the levels of TLR4 mRNA and protein, TNF-α and IL-6. Triptolide can suppress LPS-induced TLR4 expression at both the mRNA and protein levels in the mouse macrophage cell line RAW 264.7.     

Baicalin prevents LPS-induced activation of TLR4/NF-κB p65 pathway and inflammation in mice via inhibiting the expression of CD14

Previous studies have shown that baicalin,an active ingredient of the Chinese traditional medicine Huangqin,attenuates LPS-induced inflammation by inhibiting the activation of TLR4/NF-κBp65 pathway,but how it affects this pathway is unknown.It has been shown that CD14 binds directly to LPS and plays an important role in sensitizing the cells to minute quantities of LPS via chaperoning LPS molecules to the TLR4/MD-2 signaling complex.In the present study we investigated the role of CD14 in the anti-inflammatory effects of baicalin in vitro and in vivo.Exposure to LPS(1μg/mL)induced inflammatory responses in RAW264.7 cells,evidenced by marked increases in the expression of MHC II molecules and the secretion of NO and IL-6,and by activation of MyD88/NF-κB p65 signaling pathway,as well as the expression of CD14 and TLR4.These changes were dose-dependently attenuated by pretreatment baicalin(12.5–50μM),but not by baicalin post-treatment.In RAW264.7 cells without LPS stimulation,baicalin dose-dependently inhibit the protein and mRNA expression of CD14,but not TLR4.In RAW264.7 cells with CD14 knockdown,baicalin pretreatment did not prevent inflammatory responses and activation of MyD88/NF-κB p65 pathway induced by high concentrations(1000μg/mL)of LPS.Furthermore,baicalin pretreatment also inhibited the expression of CD14 and activation of MyD88/NF-κB p65 pathway in LPS-induced hepatocyte-derived HepG2 cells and intestinal epithelial-derived HT-29 cells.In mice with intraperitoneal injection of LPS and in DSS-induced UC mice,oral administration of baicalin exerted protective effects by inhibition of CD14 expression and inflammation.Taken together,we demonstrate that baicalin pretreatment prevents LPS-induced inflammation in RAW264.7 cells in CD14-dependent manner.This study supports the therapeutic use of baicalin in preventing the progression of LPS-induced inflammatory diseases.     

Plantamajoside ameliorates lipopolysaccharide-induced acute lung injury via suppressing NF-κB and MAPK activation

Despite developments in the knowledge and therapy of acute lung injury in recent decades, mortality remains high, and there is usually a lack of effective therapy. Plantamajoside, a major ingredient isolated from Plantago asiatica L. (Plantaginaceae), has been reported to have potent anti-inflammatory properties. However, the effect of plantamajoside on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice has not been investigated. The present study aimed to reveal the potential mechanism responsible for the anti-inflammatory effects of plantamajoside on LPS-induced acute lung injury in mice and in RAW264.7 cells. The results of histopathological changes as well as the lung wet-to-dry ratio and myeloperoxidase (MPO) activity showed that plantamajoside ameliorated the lung injury that was induced by LPS. qPCR and ELISA assays demonstrated that plantamajoside suppressed the production of IL-1β, IL-6 and TNF-α in a dose-dependent manner. TLR4 is an important sensor in LPS infection. Molecular studies showed that the expression of TLR4 was inhibited by plantamajoside administration. Further study was conducted on nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK) using pathways using western blots. The results showed that plantamajoside inhibited the phosphorylation of IκBα, p65, p38, JNK and ERK. All results indicated that plantamajoside has protective effect on LPS-induced ALI in mice and in RAW264.7 cells. Thus, plantamajoside may be a potential therapy for the treatment of pulmonary inflammation.     

云芝多糖B抑制血管紧张素Ⅱ诱导的巨噬细胞骨调素基因上调表达

目的探讨野生云芝多糖水溶性新组分CVPS-B对血管紧张素Ⅱ(AngⅡ)诱导的RAW264.7巨噬细胞骨调素(OPN)基因表达的影响及p38丝裂原活化蛋白激酶(p38MAPK)及其转录因子ATF-2可能的调控作用。方法用RT-PCR检测CVPS-B对AngⅡ诱导的RAW264.7巨噬细胞OPN基因表达的影响;用Western blot测定AngⅡ(1μmol.L-1)诱导RAW264.7细胞p38MAPK转录因子-激活转录因子2(ATF2)表达的时间模式;用Western blot测定CVPS-B对RAW264.7巨噬细胞p38MAPK及其转录因子ATF2磷酸化表达的影响。结果CVPS-B(10mg·L-1)在AngⅡ(1μmol·L-1)刺激前30min加入培养基抑制作用最明显,共同孵育12h,抑制率达到50.3%(P<0.01);不同浓度CVPS-B1、10、50mg·L-1在AngⅡ(1μmol·L-1)刺激前30min加入培养基,共同孵育12h,其抑制率分别为13.8%、41.2%(P<0.01)及63.7%(P<0.01)。不同浓度CVPS-B及SB202190预孵12h,SB202190在5μmol·L-1(高浓度)时能明显抑制p38MAPK的磷酸化表达,相反,CVPS-B在10、50mg·L-1(高与低浓度)时均不能明显抑制p38MAPK的磷酸化表达。CVPS-B能明显抑制ATF2的磷酸化表达并呈剂量依赖性;而且,SB202190加CVPS-B在低剂量时(SB2021901μmol·L-1加CVPS-B10mg·L-1)也能明显抑制ATF2的磷酸化表达。结论CVPS-B能明显抑制AngⅡ诱导的RAW264.7巨噬细胞OPN基因表达。CVPS-B的抑制作用可能是通过调控转录因子ATF-2的活性实现的。     

当归A_3活性部位对小鼠巨噬细胞环氧化酶-2活性及基因表达的影响

目的研究当归A3活性部位对小鼠巨噬细胞RAW264.7环氧化酶-2(cyclooxygenase-2,COX-2)活性及基因表达的影响。方法采用酶联免疫法(enzyme-line immu-nosorbnent assay,ELISA)检测前列腺素E2(prostaglandin E2,PGE2)产量及COX-2活性,采用RT-PCR和Western blot法检测COX-2 mRNA及蛋白表达水平。结果 A3(20、40、80mg.L-1)剂量依赖性地抑制LPS诱导的RAW264.7细胞PGE2产量、COX-2活性、COX-2 mRNA及蛋白表达水平增高。结论 A3能够直接抑制PGE2产量,此作用可能与抑制COX-2基因表达有关。