scholarly journals Differential Induction of the Toll-Like Receptor 4-MyD88-Dependent and -Independent Signaling Pathways by Endotoxins

2005 ◽  
Vol 73 (5) ◽  
pp. 2940-2950 ◽  
Author(s):  
Susu M. Zughaier ◽  
Shanta M. Zimmer ◽  
Anup Datta ◽  
Russell W. Carlson ◽  
David S. Stephens
Keyword(s):  
Nitric Oxide ◽  
Signaling Pathways ◽  
Lipid A ◽  
Raw 264.7 ◽  
Receptor Complex ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Nitric Oxide Release ◽  
Tnf Α ◽  
Dependent Pathway

ABSTRACT The biological response to endotoxin mediated through the Toll-like receptor 4 (TLR4)-MD-2 receptor complex is directly related to lipid A structure or configuration. Endotoxin structure may also influence activation of the MyD88-dependent and -independent signaling pathways of TLR4. To address this possibility, human macrophage-like cell lines (THP-1, U937, and MM6) or murine macrophage RAW 264.7 cells were stimulated with picomolar concentrations of highly purified endotoxins. Harvested supernatants from previously stimulated cells were also used to stimulate RAW 264.7 or 23ScCr (TLR4-deficient) macrophages (i.e., indirect induction). Neisseria meningitidis lipooligosaccharide (LOS) was a potent direct inducer of the MyD88-dependent pathway molecules tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), monocyte chemoattractant protein 1 (MCP-1), macrophage inflammatory protein 3α (MIP-3α), and the MyD88-independent molecules beta interferon (IFN-β), nitric oxide, and IFN-γ-inducible protein 10 (IP-10). Escherichia coli 55:B5 and Vibrio cholerae lipopolysaccharides (LPSs) at the same pmole/ml lipid A concentrations induced comparable levels of TNF-α, IL-1β, and MIP-3α, but significantly less IFN-β, nitric oxide, and IP-10. In contrast, LPS from Salmonella enterica serovars Minnesota and Typhimurium induced amounts of IFN-β, nitric oxide, and IP-10 similar to meningococcal LOS but much less TNF-α and MIP-3α in time course and dose-response experiments. No MyD88-dependent or -independent response to endotoxin was seen in TLR4-deficient cell lines (C3H/HeJ and 23ScCr) and response was restored in TLR4-MD-2-transfected human embryonic kidney 293 cells. Blocking the MyD88-dependent pathway by DNMyD88 resulted in significant reduction of TNF-α release but did not influence nitric oxide release. IFN-β polyclonal antibody and IFN-α/β receptor 1 antibody significantly reduced nitric oxide release. N. meningitidis endotoxin was a potent agonist of both the MyD88-dependent and -independent signaling pathways of the TLR4 receptor complex of human macrophages. E. coli 55:B5 and Vibrio cholerae LPS, at the same picomolar lipid A concentrations, selectively induced the MyD88-dependent pathway, while Salmonella LPS activated the MyD88-independent pathway.

Oxymatrine inhibits lipopolysaccharide-induced inflammation by down-regulating Toll-like receptor 4/nuclear factor-kappa B in macrophages

2015 ◽  
Vol 93 (4) ◽  
pp. 253-260 ◽  
Author(s):  
Yu Zhang ◽  
Ruhong Yan ◽  
Yae Hu
Keyword(s):  
Nitric Oxide ◽  
Interleukin 1 ◽  
Chinese Herb ◽  
Mrna Levels ◽  
Nuclear Factor ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Anti Inflammatory

Oxymatrine (OMT) is the quinolizidine alkaloid extracted from the Chinese herb Sophora flavescens Ait. that has many pharmacological effects and is used for the treatment of some inflammatory diseases. In this study, RAW264.7 cells and THP-1 differentiated macrophages were pretreated with various concentrations of OMT at 2 h prior to treatment with lipopolysaccharide (LPS) (1.0 μg/mL) for different durations. We detected the anti-inflammatory effect of OMT in LPS-stimulated macrophages and investigated the molecular mechanism. We showed that OMT pretreatment significantly inhibited the LPS-induced secretion of nitric oxide (NO), interleukin-1 beta (IL-1β), and tumor necrosis factor-alpha (TNF-α) in supernatant, attenuated the mRNA levels of inducible nitric oxide synthase (iNOS), IL-1β, TNF-α, and Toll-like receptor 4 (TLR4), increased TLR4 and phosphorylation of inhibitor of kappa B-alpha (p-IBα) in cytosol, and decreased the nuclear level of nuclear factor-κB (NF-κB) p65 in macrophages. In conclusion, OMT exerts anti-inflammatory properties in LPS-stimulated macrophages by down-regulating the TLR4/NF-κB pathway.

scholarly journals Micrococcus luteus Teichuronic Acids Activate Human and Murine Monocytic Cells in a CD14- and Toll-Like Receptor 4-Dependent Manner

2001 ◽  
Vol 69 (4) ◽  
pp. 2025-2030 ◽  
Author(s):  
Shuhua Yang ◽  
Shunji Sugawara ◽  
Toshihiko Monodane ◽  
Masahiro Nishijima ◽  
Yoshiyuki Adachi ◽  
...  
Keyword(s):  
Lipid A ◽  
Micrococcus Luteus ◽  
Dependent Manner ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Necrosis Factor Alpha ◽  
Monocytic Cells ◽  
Tnf Α

ABSTRACT Teichuronic acid (TUA), a component of the cell walls of the gram-positive organism Micrococcus luteus (formerlyMicrococcus lysodeikticus), induced inflammatory cytokines in C3H/HeN mice but not in lipopolysaccharide (LPS)-resistant C3H/HeJ mice that have a defect in the Toll-like receptor 4 (TLR4) gene, both in vivo and in vitro, similarly to LPS (T. Monodane, Y. Kawabata, S. Yang, S. Hase, and H. Takada, J. Med. Microbiol. 50:4–12, 2001). In this study, we found that purified TUA (p-TUA) induced tumor necrosis factor alpha (TNF-α) in murine monocytic J774.1 cells but not in mutant LR-9 cells expressing membrane CD14 at a lower level than the parent J774.1 cells. The TNF-α-inducing activity of p-TUA in J774.1 cells was completely inhibited by anti-mouse CD14 monoclonal antibody (MAb). p-TUA also induced interleukin-8 (IL-8) in human monocytic THP-1 cells differentiated to macrophage-like cells expressing CD14. Anti-human CD14 MAb, anti-human TLR4 MAb, and synthetic lipid A precursor IVA, an LPS antagonist, almost completely inhibited the IL-8-inducing ability of p-TUA, as well as LPS, in the differentiated THP-1 cells. Reduced p-TUA did not exhibit any activities in J774.1 or THP-1 cells. These findings strongly suggested that M. luteus TUA activates murine and human monocytic cells in a CD14- and TLR4-dependent manner, similar to LPS.

scholarly journals Asperuloside and Asperulosidic Acid Exert an Anti-Inflammatory Effect via Suppression of the NF-κB and MAPK Signaling Pathways in LPS-Induced RAW 264.7 Macrophages

2018 ◽  
Vol 19 (7) ◽  
pp. 2027 ◽  
Author(s):  
Jingyu He ◽  
Xianyuan Lu ◽  
Ting Wei ◽  
Yaqian Dong ◽  
Zheng Cai ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Methyl Ester ◽  
Signaling Pathways ◽  
Mapk Signaling ◽  
Raw 264.7 Cells ◽  
Raw 264.7 ◽  
Tnf Α ◽  
Anti Inflammatory ◽  
Mapk Signaling Pathways ◽  
Inflammatory Effect

Hedyotis diffusa is a folk herb that is used for treating inflammation-related diseases in Asia. Previous studies have found that iridoids in H. diffusa play an important role in its anti-inflammatory activity. This study aimed to investigate the anti-inflammatory effect and potential mechanism of five iridoids (asperuloside (ASP), asperulosidic acid (ASPA), desacetyl asperulosidic acid (DAA), scandoside methyl ester (SME), and E-6-O-p-coumaroyl scandoside methyl ester (CSME)) that are presented in H. diffusa using lipopolysaccharide (LPS)—induced RAW 264.7 cells. ASP and ASPA significantly decreased the production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in parallel with the inhibition of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), TNF-α, and IL-6 mRNA expression in LPS-induced RAW 264.7 cells. ASP treatment suppressed the phosphorylation of the inhibitors of nuclear factor-kappaB alpha (IκB-α), p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). The inhibitory effect of ASPA was similar to that of ASP, except for p38 phosphorylation. In summary, the anti-inflammatory effects of ASP and ASPA are related to the inhibition of inflammatory cytokines and mediators via suppression of the NF-κB and mitogen-activated protein kinase (MAPK) signaling pathways, which provides scientific evidence for the potential application of H. diffusa.

Mycoplasma arthritidis superantigen (MAM)-induced macrophage nitric oxide release is MHC class ii restricted, interferonγ dependent, and toll-like receptor 4 independent

2003 ◽  
Vol 286 (2) ◽  
pp. 345-354 ◽  
Author(s):  
Fátima Ribeiro-Dias ◽  
Marina Tiemi Shio ◽  
Jorge Timenetsky ◽  
Ana Paula Camilo Oliane ◽  
Camila Cardoso Metran ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Mhc Class Ii ◽  
Class Ii ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Mycoplasma Arthritidis ◽  
Nitric Oxide Release

scholarly journals Aktivitas Imunomodulator Ekstrak Metanol dan Fraksi buah Talok (Muntingia calabura L.) pada Sel RAW 264.7

2021 ◽  
Vol 6 (2) ◽  
pp. 82
Author(s):  
Tanti Azizah Sujono ◽  
Ika Trisharyanti Dian Kusumowati ◽  
Rima Munawaroh
Keyword(s):  
Tumor Necrosis ◽  
Raw 264.7 ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Reverse Transcription Pcr ◽  
Tnf Α ◽  
Oxide Synthase ◽  
Necrosis Factor ◽  
Muntingia Calabura ◽  
Inducible Nitric Oxide

<p>Buah talok (<em>Muntingia</em><em> calabura</em> L) secara empiris telah diketahui mempunyai banyak manfaat bagi kesehatan, diantaranya adalah sebagai imunomodulator. Namun mekanisme aksinya sebagai imunomodulator belum diketahui secara pasti. Penelitian ini bertujuan untuk mengevaluasi efek imunomodulator ekstrak metanolik dan fraksi buah talok pada sel makrofag RAW 264.7. Sel RAW 264.7 diberi perlakuan dengan ekstrak metanolik buah talok (EMBT), fraksi heksan buah talok (FHBT), fraksi diklorometana buah talok (FDBT), fraksi etil asetat buah talok (FEABT) serta kelompok kontrol sel (KS), kontrol lipopolisakarida (LPS) dan deksametason. Viabilitas sel diukur dengan metode <em>MTT</em> <em>assay</em> dilanjutkan isolasi RNA, pembuatan cDNA dan PCR. Level ekspresi mRNA dari gen-gen seperti toll like receptor 4 (TLR4), interferon (IFN)-ɣ, interleukin (IL)-6, inducible nitric oxide synthase (iNOS), tumor necrosis factor (TNF)-α pada sel RAW 264.7 yang diinduksi lipopolisakarida (LPS) dianalisis dengan metode reverse transcription-PCR. Hasil penelitian menunjukkan bahwa deksametason menghambat ekspresi iNOS, IL-6, TNF-α, TLR4, IFN- ɣ dan NF-kB dibandingkan dengan kontrol sel dan LPS. Hal ini mengindikasikan bahwa deksametason mempunyai aktivitas antiinflamasi. Ekstrak metanolik (EMBT) dan fraksi buah talok (FHBT, FDBT dan FEABT) menurunkan ekspresi gen iNOS, TNF-α, IL-6, IFN- ɣ dan NF-kB jika dibandingkan dengan kontrol sel dan LPS, hal ini menunjukkan adanya aktivitas antiinflamasi. Ekstrak metanolik dan fraksi buah talok mempunyai  aktivitas imunomodulator melalui penghambatan inflamasi dengan menurunkan ekspresi gen iNOS, TNF-α, IL-6, IFN- ɣ dan NF-kB pada sel RAW 264.7 yang diinduksi LPS. </p>

scholarly journals Auraptene, a Monoterpene Coumarin, Inhibits LTA-Induced Inflammatory Mediators via Modulating NF-κB/MAPKs Signaling Pathways

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Chih-Hsuan Hsia ◽  
Thanasekaran Jayakumar ◽  
Wan-Jung Lu ◽  
Joen-Rong Sheu ◽  
Chih-Wei Hsia ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Signaling Pathways ◽  
Nuclear Translocation ◽  
Polyacrylamide Gel Electrophoresis ◽  
Raw 264.7 Cells ◽  
No Production ◽  
Raw 264.7 ◽  
Tnf Α ◽  
Cox 2 ◽  
Anti Inflammatory

Objective. Oxidative stress-mediated inflammatory events involve in the progress of several diseases such as asthma, cancers, and multiple sclerosis. Auraptene (AU), a natural prenyloxycoumarin, possesses numerous pharmacological activities. Here, the anti-inflammatory effects of AU were investigated in lipoteichoic acid- (LTA-) induced macrophage cells (RAW 264.7). Methods. The expression of cyclooxygenase (COX-2), tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), and inducible nitric oxide synthase (iNOS) and the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2, p38 MAPK, c-Jun N-terminal kinase (JNK), heme oxygenase (HO-1), p65, and IκBα were all identified by western blotting assay. The level of nitric oxide (NO) was measured by spectrometer analysis. The nuclear translocation of p65 nuclear factor kappa B (NF-κB) was assessed by the confocal microscopic staining method. Native polyacrylamide gel electrophoresis was performed to perceive the activity of antioxidant enzyme catalase (CAT). Results. AU expressively reduced NO production and COX-2, TNF-α, IL-1 β, and iNOS expression in LTA-stimulated cells. AU at higher concentration (10 µM) inhibited ERK and JNK, but not p38 phosphorylation induced by LTA. Moreover, AU blocked IκB and p65 phosphorylation, and p65 nuclear translocation. However, AU pretreatment was not effective on antioxidant HO-1 expression, CAT activity, and reduced glutathione (GSH, a nonenzymatic antioxidant), in LTA-induced RAW 264.7 cells. Conclusion. The findings of this study advocate that AU shows anti-inflammatory effects via reducing NF-κB/MAPKs signaling pathways.

scholarly journals Immunostimulatory Effects of Chitooligosaccharides on RAW 264.7 Mouse Macrophages via Regulation of the MAPK and PI3K/Akt Signaling Pathways

Marine Drugs ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 36 ◽  
Author(s):  
Yue Yang ◽  
Ronge Xing ◽  
Song Liu ◽  
Yukun Qin ◽  
Kecheng Li ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Signaling Pathways ◽  
Nuclear Translocation ◽  
Akt Signaling ◽  
Water Soluble ◽  
Raw 264.7 Cells ◽  
Raw 264.7 ◽  
Tnf Α ◽  
Mitogen Activated Protein ◽  
Chitin And Chitosan

Chitooligosaccharides (COS), the hydrolyzed products of chitin and chitosan, can be obtained by various methods. In this study, water-soluble COS were prepared from α- and β-chitosan by microwave-assisted degradation and their immunostimulatory effects were investigated in RAW 264.7 macrophages. The results indicated that α-COS were more active than β-COS in promoting the production of nitric oxide (NO) and cytokines, such as tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6). Quantitative real-time reverse transcription polymerase chain reaction and Western blotting indicated that COS also enhanced the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and TNF-α. Further analyses demonstrated that COS induced the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38, p85 and Akt, and the nuclear translocation of p65, indicating that they are able to activate the mitogen-activated protein kinases (MAPKs) and phosphoinositide 3-kinases (PI3K)/Akt signaling pathways dependent on nuclear factor (NF)-κB activation. In conclusion, COS activate RAW 264.7 cells via the MAPK and PI3K/Akt signaling pathways and are potential novel immune potentiators.

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