LPS receptor CD14 participates in release of TNF-α in RAW 264.7 and peritoneal cells but not in Kupffer cells

Lipopolysaccharide (LPS) is a bacterial polymer that stimulates macrophages to release tumor necrosis factor-α (TNF-α). In macrophages (RAW 264.7 and peritoneal cells), LPS binds to the CD14 surface receptor as the first step toward signaling. Liver macrophages, Kupffer cells, are the most numerous fixed-tissue macrophage in the body. The presence of CD14 on Kupffer cells and its role in LPS stimulation of TNF-α were examined. TNF-α release by Kupffer cells after LPS stimulation was the same in the presence and absence of serum. RAW 264.7 and peritoneal cells, which utilize the CD14 receptor, released significantly less TNF-α after LPS stimulation in the absence of serum because of the absence of LPS-binding protein. Phosphatidylinositol-phospholipase C treatment, which cleaves the CD14 receptor, decreased LPS-stimulated TNF-α release by RAW 264.7 cells but not by Kupffer cells. Deacylated LPS (dLPS) competes with LPS at the CD14 receptor when incubated in a ratio of 100:1 (dLPS/LPS). Such competition blocked LPS-stimulated TNF-α release from RAW 264.7 cells but not from Kupffer cells. Western and fluorescence-activated cell sorter analysis directly demonstrated the presence of CD14 on RAW 264.7 cells and murine peritoneal cells but showed only minimal amounts of CD14 in murine Kupffer cells. LPS stimulation did not increase the amount of CD14 detectable on mouse Kupffer cells. CD14 expression is very low in Kupffer cells, and LPS-stimulated TNF-α release is independent of CD14 in these cells.

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Pronase destroys the lipopolysaccharide receptor CD14 on Kupffer cells

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1999.276.3.g591 ◽

1999 ◽

Vol 276 (3) ◽

pp. G591-G598 ◽

Cited By ~ 7

Author(s):

Kenichi Ikejima ◽

Nobuyuki Enomoto ◽

Vitor Seabra ◽

Ayako Ikejima ◽

David A. Brenner ◽

...

Keyword(s):

Intracellular Calcium ◽

Kupffer Cells ◽

Peritoneal Macrophages ◽

Raw 264.7 Cells ◽

Rat Serum ◽

Tnf Α ◽

Collagenase Perfusion ◽

Factor Α ◽

Serum Dependent ◽

In Cells

CD14 is a lipopolysaccharide (LPS) receptor distributed largely in macrophages, monocytes, and neutrophils; however, the role of CD14 in activation of Kupffer cells by LPS remains controversial. The purpose of this study was to determine if different methods used to isolate Kupffer cells affect CD14. Kupffer cells were isolated by collagenase (0.025%) or collagenase-Pronase (0.02%) perfusion and differential centrifugation using Percoll gradients and cultured for 24 h before experiments. CD14 mRNA was detected by RT-PCR from Kupffer cell total RNA as well as from peritoneal macrophages. Western blotting showed that Kupffer cells prepared with collagenase possess CD14; however, it was absent in cells obtained by collagenase-Pronase perfusion. Intracellular calcium in Kupffer cells prepared with collagenase was increased transiently to levels around 300 nM by addition of LPS with 5% rat serum, which contains LPS binding protein. This increase in intracellular calcium was totally serum dependent. Moreover, LPS-induced increases in intracellular calcium in Kupffer cells were blunted significantly (40% of controls) when cells were treated with phosphatidylinositol-specific phospholipase C, which cleaves CD14 from the plasma membrane. However, intracellular calcium did not increase when LPS was added to cells prepared by collagenase-Pronase perfusion even in the presence of serum. These cells were viable, however, because ATP increased intracellular calcium to the same levels as cells prepared with collagenase perfusion. Tumor necrosis factor-α (TNF-α) mRNA was increased in Kupffer cells prepared with collagenase perfusion 1 h after addition of LPS, an effect potentiated over twofold by serum; however, serum did not increase TNF-α mRNA in cells isolated via collagenase-Pronase perfusion. Moreover, treatment with Pronase rapidly decreased CD14 on mouse macrophages (RAW 264.7 cells) and Kupffer cells. These findings indicate that Pronase cleaves CD14 from Kupffer cells, whereas collagenase perfusion does not, providing an explanation for why Kupffer cells do not exhibit a CD14-mediated pathway when prepared with procedures using Pronase. It is concluded that Kupffer cells indeed contain a functional CD14 LPS receptor when prepared gently.

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Hypoxia enhances lysosomal TNF-α degradation in mouse peritoneal macrophages

AJP Cell Physiology ◽

10.1152/ajpcell.00572.2007 ◽

2008 ◽

Vol 295 (1) ◽

pp. C2-C12 ◽

Cited By ~ 15

Author(s):

Nitza Lahat ◽

Michal A. Rahat ◽

Amalia Kinarty ◽

Lea Weiss-Cerem ◽

Sigalit Pinchevski ◽

...

Keyword(s):

Peritoneal Macrophages ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Mrna Levels ◽

Tnf Α ◽

Primary Mouse ◽

Factor Α ◽

Secretory Lysosomes ◽

Mouse Peritoneal Macrophages ◽

Necrosis Factor

Infection, simulated by lipopolysaccharide (LPS), is a potent stimulator of tumor necrosis factor-α (TNF-α) production, and hypoxia often synergizes with LPS to induce higher levels of the secreted cytokine. However, we show that in primary mouse peritoneal macrophages and in three mouse peritoneal macrophage cell lines (RAW 264.7, J774A.1, and PMJ-2R), hypoxia (O2 < 0.3%) reduces the secretion of LPS-induced TNF-α ( P < 0.01). In RAW 264.7 cells this reduction was not regulated transcriptionally as TNF-α mRNA levels remained unchanged. Rather, hypoxia and LPS reduced the intracellular levels of TNF-α by twofold ( P < 0.01) by enhancing its degradation in the lysosomes and inhibiting its secretion via secretory lysosomes, as shown by confocal microscopy and verified by the use of the lysosome inhibitor Bafilomycin A1. In addition, although hypoxia did not change the accumulation of the soluble receptor TNF-RII, it increased its binding to the secreted TNF-α by twofold ( P < 0.05). We suggest that these two posttranslational regulatory checkpoints coexist in hypoxia and may partially explain the reduced secretion and diminished biological activity of TNF-α in hypoxic peritoneal macrophages.

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Investigation of the Mechanism of Anti-Inflammatory Action and Cytotoxicity of a Semipurified Fraction and Isolated Compounds From the Leaf of Peltophorum africanum (Fabaceae)

Journal of Evidence-Based Complementary & Alternative Medicine ◽

10.1177/2156587217717417 ◽

2017 ◽

Vol 22 (4) ◽

pp. 840-845 ◽

Cited By ~ 3

Author(s):

Salmon A. Adebayo ◽

Helen C. Steel ◽

Leshweni J. Shai ◽

Jacobus N. Eloff

Keyword(s):

Mechanism Of Action ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Tnf Α ◽

Raw 264.7 Macrophage Cells ◽

Antiviral Activities ◽

Anti Inflammatory ◽

Factor Α ◽

Inflammatory Action

Peltophorum africanum extracts have been shown to possess many important medicinal benefits, including anti-inflammatory and antiviral activities. However, the mechanism of action is poorly understood. The mechanism of anti-inflammatory action was determined by measuring the synthesis of cytokines in lipopolysaccharide (LPS) stimulated RAW 264.7 macrophage cells in vitro. Compound 1 (CP1), compound 2 (CP2), and fraction F3.3.0 (F3.3.0) significantly reduced the synthesis of interleukin 1β (IL-1β) from RAW 264.7 cells (1.18, 1.32, and 0.92 ng/mL), respectively. Similarly, CP1, CP2, and F3.3.0 inhibited the production of IL-2 and tumor necrosis factor–α (TNF-α) by RAW 264.7 cells (0.41, 0.60, 0.74 and 0.11, 0.27, 0.24 ng/mL, respectively. In addition, CP1 and CP2 had lower cytotoxicity toward RAW 264.7 cells, with CP2 indicating the lowest cytotoxicity (LD50 = 207.88 µg/mL). The mechanism of action was found to be via the inhibition of pro-inflammation cytokines (IL-1 β and TNF-α). This observation may support the use of P africanum to treat pain-related conditions.

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Comparing the protective effects of resveratrol, curcumin and sulforaphane against LPS/IFN-γ-mediated inflammation in doxorubicin-treated macrophages

Scientific Reports ◽

10.1038/s41598-020-80804-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Haidy A. Saleh ◽

Eman Ramdan ◽

Mohey M. Elmazar ◽

Hassan M. E. Azzazy ◽

Anwar Abdelnaser

Keyword(s):

Nitric Oxide ◽

Inflammatory Response ◽

Raw 264.7 Cells ◽

Inos Mrna ◽

No Production ◽

Raw 264.7 ◽

Mrna Levels ◽

Protective Effects ◽

Tnf Α ◽

Ifn Γ

AbstractDoxorubicin (DOX) chemotherapy is associated with the release of inflammatory cytokines from macrophages. This has been suggested to be, in part, due to DOX-mediated leakage of endotoxins from gut microflora, which activate Toll-like receptor 4 (TLR4) signaling in macrophages, causing severe inflammation. However, the direct function of DOX on macrophages is still unknown. In the present study, we tested the hypothesis that DOX alone is incapable of stimulating inflammatory response in macrophages. Then, we compared the anti-inflammatory effects of curcumin (CUR), resveratrol (RES) and sulforaphane (SFN) against lipopolysaccharide/interferon-gamma (LPS/IFN-γ)-mediated inflammation in the absence or presence of DOX. For this purpose, RAW 264.7 cells were stimulated with LPS/IFN-γ (10 ng/mL/10 U/mL) in the absence or presence of DOX (0.1 µM). Our results showed that DOX alone is incapable of stimulating an inflammatory response in RAW 264.7 macrophages. Furthermore, after 24 h of incubation with LPS/IFN-γ, a significant increase in tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and inducible nitric oxide synthase (iNOS) mRNA levels was observed. Similarly, nitric oxide (NO) production and TNF-α and IL-6 protein levels were significantly upregulated. Moreover, in LPS/IFN-γ-treated macrophages, the microRNAs (miRNAs) miR-146a, miR-155, and miR-21 were significantly overexpressed. Interestingly, upon testing CUR, RES, and SFN against LPS/IFN-γ-mediated inflammation, only SFN was able to significantly reverse the LPS/IFN-γ-mediated induction of iNOS, TNF-α and IL-6 and attenuate miR-146a and miR-155 levels. In conclusion, SFN, at the transcriptional and posttranscriptional levels, exhibits potent immunomodulatory action against LPS/IFN-γ-stimulated macrophages, which may indicate SFN as a potential treatment for DOX-associated inflammation.

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Role of TNF-α-Inducing Protein Secreted by Helicobacter pylori as a Tumor Promoter in Gastric Cancer and Emerging Preventive Strategies

Toxins ◽

10.3390/toxins13030181 ◽

2021 ◽

Vol 13 (3) ◽

pp. 181

Author(s):

Masami Suganuma ◽

Tatsuro Watanabe ◽

Eisaburo Sueoka ◽

In Kyoung Lim ◽

Hirota Fujiki

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Cell Surface Receptor ◽

Tumor Promoter ◽

Cancer Development ◽

Human Gastric Cancer ◽

Tnf Α ◽

Surface Receptor ◽

H Pylori ◽

Factor Α

The tumor necrosis factor-α (TNF-α)-inducing protein (tipα) gene family, comprising Helicobacter pylori membrane protein 1 (hp-mp1) and tipα, has been identified as a tumor promoter, contributing to H. pylori carcinogenicity. Tipα is a unique H. pylori protein with no similarity to other pathogenicity factors, CagA, VacA, and urease. American H. pylori strains cause human gastric cancer, whereas African strains cause gastritis. The presence of Tipα in American and Euro-Asian strains suggests its involvement in human gastric cancer development. Tipα secreted from H. pylori stimulates gastric cancer development by inducing TNF-α, an endogenous tumor promoter, through its interaction with nucleolin, a Tipα receptor. This review covers the following topics: tumor-promoting activity of the Tipα family members HP-MP1 and Tipα, the mechanism underlying this activity of Tipα via binding to the cell-surface receptor, nucleolin, the crystal structure of rdel-Tipα and N-terminal truncated rTipα, inhibition of Tipα-associated gastric carcinogenesis by tumor suppressor B-cell translocation gene 2 (BTG2/TIS21), and new strategies to prevent and treat gastric cancer. Thus, Tipα contributes to the carcinogenicity of H. pylori by a mechanism that differs from those of CagA and VacA.

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A New Flavonol From Saussurea involucrata With Anti-Inflammatory Activity

Natural Product Communications ◽

10.1177/1934578x211007638 ◽

2021 ◽

Vol 16 (5) ◽

pp. 1934578X2110076

Author(s):

Sheng Pan ◽

Zi-Guan Zhu

Keyword(s):

Nitric Oxide ◽

Aerial Part ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Spectroscopic Methods ◽

Soluble Extract ◽

Saussurea Involucrata ◽

Tnf Α ◽

Anti Inflammatory

A new flavonol named 6-(2'',3''-epoxy-3''-methylbutyl)-resokaempferol (1), together with five known compounds (2-6) were isolated from the EtOAc-soluble extract of the aerial part of Saussurea involucrata. Their structures were elucidated on the basis of spectroscopic methods. All compounds were evaluated for their anti-inflammatory effects by measuring the production of nitric oxide (NO) and TNF-α in vitro. Among them, compound 1 showed potential inhibitory activity on the production of NO and TNF-α in LPS-induced RAW 264.7 cells with IC50 values of 48.0 ± 1.5 and 41.4 ± 1.7 µM, respectively.

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Nepetoidin B from Salvia plebeia R. Br. Inhibits Inflammation by Modulating the NF-κB and Nrf2/HO-1 Signaling Pathways in Macrophage Cells

Antioxidants ◽

10.3390/antiox10081208 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1208

Author(s):

Mina Kim ◽

Ji Yeong Kim ◽

Hee Sun Yang ◽

Jeong-Sook Choe ◽

In Guk Hwang

Keyword(s):

Defense Mechanisms ◽

Inflammatory Diseases ◽

Cell Damage ◽

Treated Group ◽

Raw 264.7 Cells ◽

Resonance Spectroscopy ◽

Raw 264.7 ◽

Related Factor ◽

Anti Inflammatory ◽

Factor Α

Salvia plebeia has been used to treat a variety of inflammatory diseases, as well as colds and bronchitis. Macrophages have antioxidant defense mechanisms to cope with the intracellular reactive oxygen species (ROS) produced as part of the immune response. The nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase (HO)-1 pathway in inflamed macrophages is an appealing target due to its protective effect against ROS-induced cell damage. In this study, nepetoidin B (NeB) was first isolated from S. plebeia and identified by nuclear magnetic resonance spectroscopy. NeB reduced pro-inflammatory mediators (nitric oxide and prostaglandin E2) and cytokines (tumor necrosis factor-α, interleukin (IL)-6, and IL-1β) in LPS-activated RAW 264.7 cells by inhibiting the NF-κB signaling pathway. In the NeB-treated group, catalase and superoxide dismutase levels were significantly higher, and ROS expression decreased. By activating Nrf2 signaling, NeB enhanced HO-1 expression. Furthermore, when the cells were pretreated with tin protoporphyrin (an HO-1 inhibitor), the anti-inflammatory effects of NeB were reduced. Therefore, NeB may activate the Nrf2/ HO-1 pathway. These results reveal the NeB isolated from S. plebeia exerts anti-inflammatory effects by modulating NF-κB signaling and activating the Nrf2/HO-1 pathway in LPS-stimulated RAW 264.7 cells.

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Alpha-Lipoic Acid Suppresses Extracellular Histone-Induced Release of the Infammatory Mediator Tumor Necrosis Factor-α by Macrophages

Cellular Physiology and Biochemistry ◽

10.1159/000480217 ◽

2017 ◽

Vol 42 (6) ◽

pp. 2559-2568 ◽

Cited By ~ 3

Author(s):

Ping Chang ◽

Juan Liu ◽

Ying Yu ◽

Shao-Ye Cui ◽

Zhen-Hui Guo ◽

...

Keyword(s):

Tumor Necrosis Factor ◽

Signaling Pathways ◽

Tumor Necrosis ◽

Tumor Necrosis Factor Α ◽

Raw 264.7 ◽

Alpha Lipoic Acid ◽

Tnf Α ◽

Extracellular Histones ◽

Factor Α ◽

Necrosis Factor

Background/Aims: This study investigated signaling pathways via which extracellular histones induce the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) release from the macrophage cell line RAW 264.7 and the anti-inflammatory efficacy of the antioxidant alpha-lipoic acid (ALA). Methods: ELISA and western blotting analyses were conducted to detect the release of TNF-α from histone-stimulated RAW 264.7 macrophages and the associated phospho-activation of MAPKs (ERK and p38) and NF-κB p65. The effects of ALA on the release of TNF-α and phospho-activation of the MAPKs and NF-κB p65 were studied. P < 0.05 was considered statistically significant. Results: Extracellular histones dose-dependently induced TNF-α release from RAW 264.7 cells and increased the phosphorylation of p38, ERK, and NF-κB p65. TNF-α release was markedly suppressed by p38, ERK, and NF-kB inhibitors. ALA reduced histone-induced TNF-α release, ERK/p38 MAPK activation, and NF-kB activation without affecting macrophage viability. Conclusion: Histones induce TNF-α release from macrophages by activating the MAPK and NF-kB signaling pathways, while ALA suppresses this response by inhibiting ERK, p38 and NF-kB. These findings identify potentially critical inflammatory signaling pathways in sepsis and molecular targets for sepsis treatment.

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Febrile-range temperature modifies cytokine gene expression in LPS-stimulated macrophages by differentially modifying NF-κB recruitment to cytokine gene promoters

AJP Cell Physiology ◽

10.1152/ajpcell.00346.2009 ◽

2010 ◽

Vol 298 (1) ◽

pp. C171-C181 ◽

Cited By ~ 35

Author(s):

Zachary A. Cooper ◽

Arundhati Ghosh ◽

Aditi Gupta ◽

Tapan Maity ◽

Ivor J. Benjamin ◽

...

Keyword(s):

Gene Expression ◽

Receptor Activation ◽

Cytokine Gene Expression ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Heat Shock Factor 1 ◽

Gene Promoters ◽

Cytokine Gene ◽

Tnf Α

We previously showed that exposure to febrile-range temperatures (FRT, 39.5–40°C) reduces LPS-induced TNF-α expression, in part through the direct interaction of heat shock factor-1 (HSF1) with the TNF-α gene promoter. However, it is not known whether exposure to FRT also modifies more proximal LPS-induced signaling events. Using HSF1-null mice, we confirmed that HSF1 is required for FRT-induced repression of TNF-α in vitro by LPS-stimulated bone marrow-derived macrophages and in vivo in mice challenged intratracheally with LPS. Exposing LPS-stimulated RAW 264.7 mouse macrophages to FRT reduced TNF-α expression while increasing IL-1β expression despite the two genes sharing a common myeloid differentiation protein-88 (MyD88)-dependent pathway. Global activation of the three LPS-induced signaling intermediates that lead to cytokine gene expression, ERK and p38 MAPKs and NF-κB, was not affected by exposing RAW 264.7 cells to FRT as assessed by ERK and p38 phosphorylation and NF-κB in vitro DNA-binding activity and activation of a NF-κB-dependent synthetic promoter. However, chromatin immunoprecipitation (ChIP) analysis demonstrated that exposure to FRT reduced LPS-induced recruitment of NF-κB p65 to the TNF-α promoter while simultaneously increasing its recruitment to the IL-1β promoter. These data suggest that FRT exerts its effects on cytokine gene expression in a gene-specific manner through distal effects on promoter activation rather than proximal receptor activation and signal transduction.

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Nutritional Value and Anti-inflammation Activity of Misutkaru with Added Gryllus bimaculatus Powder

Asian Journal of Beauty and Cosmetology ◽

10.20402/ajbc.2021.0203 ◽

2021 ◽

Vol 19 (3) ◽

pp. 467-476

Author(s):

Jung-Soon Han

Keyword(s):

Amino Acid ◽

Inflammatory Cytokines ◽

Nutritional Value ◽

Interleukin 1 ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Gryllus Bimaculatus ◽

Necrosis Factor Alpha ◽

Automatic Amino Acid Analyzer ◽

Tnf Α

Purpose: This study investigated the nutritional value of Misutkaru with added Gryllus bimaculatus powder (GBM) and its applicability as a healthy functional food.Methods: Chemical analysis of the moisture, crude fat, protein, and mineral contents was performed in accordance with the Association of Official Analytical Chemists (AOAC) guidelines. The amino acid and fatty acid compositions were analyzed using an automatic amino acid analyzer and gas chromatography, respectively. The levels of inflammatory cytokines tumor necrosis factor‑alpha (TNF-α), interleukin 1 beta (IL-1β), and interleukin 6 (IL‑6) induced by lipopolysaccharides in RAW 264.7 cells were measured.Results: The general composition per 100 g of GBM was 41.87 g protein, 19.75 g fat, and 28.52 g carbohydrates. The mineral content per 100 g of GBM was 889.66 mg calcium, 1189.73 mg potassium, 220.36 mg magnesium, 207.51 mg sodium, 694.81 mg phosphorus, and 15.50 mg zinc. In particular, valine (21.361 mg/kg), leucine (29.180 mg/kg), and isoleucine (15.562 mg/kg) were abundant in GBM. GBM also effectively downregulated the production of the inflammatory cytokines TNF-α, IL-1β, and IL-6 in RAW 264.7 macrophages.Conclusion: Misutkaru with added Gryllus bimaculatus powder may have potential for application in the development of food materials or foods to prevent muscle loss in elderly individuals and sarcopenia patients, build muscle, and prevent increase in blood lipid concentrations in middle aged people. In particular, as Gryllus bimaculatus is low in fat and carbohydrates, it can be used as a diet material.

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