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

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.

Download Full-text

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

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2021/5319584 ◽

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.

Download Full-text

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

International Journal of Molecular Sciences ◽

10.3390/ijms19072027 ◽

2018 ◽

Vol 19 (7) ◽

pp. 2027 ◽

Cited By ~ 18

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.

Download Full-text

Suppression of Nitric Oxide Synthase by Thienodolin in Lipopolysaccharide-stimulated RAW 264.7 Murine Macrophage Cells

Natural Product Communications ◽

10.1177/1934578x1200700625 ◽

2012 ◽

Vol 7 (6) ◽

pp. 1934578X1200700 ◽

Cited By ~ 1

Author(s):

Eun-Jung Park ◽

John M. Pezzuto ◽

Kyoung Hwa Jang ◽

Sang-Jip Nam ◽

Sergio A. Bucarey ◽

...

Keyword(s):

Nitric Oxide ◽

Nitric Oxide Synthase ◽

Nuclear Translocation ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Dependent Manner ◽

Signal Transducers ◽

Protein Levels ◽

Mitogen Activated Protein ◽

Oxide Synthase

The measurement of nitric oxide in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells is used as a model for evaluating the anti-inflammatory or chemopreventive potential of substances. Thienodolin, isolated from a Streptomyces sp. derived from Chilean marine sediment, inhibited nitric oxide production in LPS-stimulated RAW 264.7 cells (IC50 = 17.2 ± 1.2 μM). At both the mRNA and protein levels, inducible nitric oxide synthase (iNOS) was suppressed in a dose-dependent manner. Mitogen-activated protein kinases (MAPKs), one major upstream signaling pathway involved in the transcription of iNOS, were not affected by treatment of thienodolin. However, the compound blocked the degradation of IκBα resulting in inhibition of NF-κB p65 nuclear translocation, and inhibited the phosphorylation of signal transducers and activators of transcription 1 (STAT1) at Tyr701. This study supports further exploration of thienodolin as a potential therapeutic agent with a unique mechanistic activity.

Download Full-text

Anti-Inflammatory Effects of Ribes diacanthum Pall Mediated via Regulation of Nrf2/HO-1 and NF-κB Signaling Pathways in LPS-Stimulated RAW 264.7 Macrophages and a TPA-Induced Dermatitis Animal Model

Antioxidants ◽

10.3390/antiox9070622 ◽

2020 ◽

Vol 9 (7) ◽

pp. 622

Author(s):

Na Yeon Kim ◽

Sun Hee Cheong ◽

Kun Jong Lee ◽

Dai-Eun Sok ◽

Mee Ree Kim

Keyword(s):

Nitric Oxide ◽

Animal Model ◽

Nuclear Translocation ◽

Raw 264.7 Cells ◽

Heme Oxygenase 1 ◽

Raw 264.7 ◽

Nuclear Factor ◽

Raw 264.7 Macrophages ◽

Tnf Α ◽

Anti Inflammatory

Ribes diacanthum Pall (RDP) is a Mongolian traditional medicine used to treat renal inflammation. In the present study, we initially investigated the anti-inflammatory effects and mechanisms of action of ethylacetate extract of RDP (EARDP) in RAW 264.7 macrophages stimulated by lipopolysaccharide (LPS) and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced dermatitis in mice. We demonstrated that EARDP protected against LPS-induced cell death by inhibiting intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) production, as well as the synthesis of pro-inflammatory mediators and cytokines, such as nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1β. EARDP inhibited the phosphorylation and degradation of inhibitory κB-α (IκB-α) and the activation of nuclear factor (NF)-κB, indicating that the anti-inflammatory effect of EARDP was mediated via the suppression of NF-κB nuclear translocation. In addition, EARDP induced the heme oxygenase-1 (HO-1) expression and nuclear translocation of nuclear factor-E2-related factor 2 (Nrf2), indicating that EARDP induced HO-1 via the Nrf2 pathway in RAW 264.7 cells. Furthermore, EARDP significantly suppressed the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW 264.7 macrophages. However, ZnPP, a specific inhibitor of HO-1, reversed the EARDP-mediated inhibition of NO and TNF-α production in LPS-stimulated RAW 264.7 macrophages. EARDP blocked the phosphorylation of mitogen-activated protein kinase (MAPK) and Akt in LPS-stimulated RAW 264.7 cells. In the in vivo animal model, EARDP significantly and dose-dependently reduced TPA-induced secretion of TNF-α and IL-6 in mouse ear. Based on these results, EARDP represents a promising natural compound, protective against oxidative stress and inflammatory diseases.

Download Full-text

Inhibition of Skin Inflammation by Scytonemin, an Ultraviolet Sunscreen Pigment

Marine Drugs ◽

10.3390/md18060300 ◽

2020 ◽

Vol 18 (6) ◽

pp. 300

Author(s):

Moo Rim Kang ◽

Sun Ah Jo ◽

Hyunju Lee ◽

Yeo Dae Yoon ◽

Joo-Hee Kwon ◽

...

Keyword(s):

Nitric Oxide ◽

Nuclear Translocation ◽

Skin Inflammation ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Blue Green Algae ◽

Tnf Α ◽

Anti Inflammatory

Scytonemin is a yellow-green ultraviolet sunscreen pigment present in different genera of aquatic and terrestrial blue-green algae, including marine cyanobacteria. In the present study, the anti-inflammatory activities of scytonemin were evaluated in vitro and in vivo. Topical application of scytonemin inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear swelling in BALB/c mice. The expression of tumor necrosis factor-α (TNF-α) and inducible nitric oxide synthase (iNOS) was also suppressed by scytonemin treatment in the TPA-treated ear of BALB/c mice. In addition, scytonemin inhibited lipopolysaccharide (LPS)-induced production of TNF-α and nitric oxide (NO) in RAW 264.7 cells, a murine macrophage-like cell line, and the mRNA expressions of TNF-α and iNOS were also suppressed by scytonemin in LPS-stimulated RAW 264.7 cells. Further study demonstrated that LPS-induced NF-κB activity was significantly suppressed by scytonemin treatment in RAW 264.7 cells. Our results also showed that the degradation of IκBα and nuclear translocation of the p65 subunit were blocked by scytonemin in LPS-stimulated RAW 264.7 cells. Collectively, these results suggest that scytonemin inhibits skin inflammation by blocking the expression of inflammatory mediators, and the anti-inflammatory effect of scytonemin is mediated, at least in part, by down-regulation of NF-κB activity. Our results also suggest that scytonemin might be used as a multi-function skin care ingredient for UV protection and anti-inflammation.

Download Full-text

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.

Download Full-text

Phaseolin Attenuates Lipopolysaccharide-Induced Inflammation in RAW 264.7 Cells and Zebrafish

Biomedicines ◽

10.3390/biomedicines9040420 ◽

2021 ◽

Vol 9 (4) ◽

pp. 420

Author(s):

Su-Jung Hwang ◽

Ye-Seul Song ◽

Hyo-Jong Lee

Keyword(s):

Nitric Oxide ◽

Nuclear Translocation ◽

Raw 264.7 Cells ◽

Network Pharmacology ◽

Raw 264.7 ◽

Dependent Manner ◽

Bioactive Constituents

Kushen (Radix Sophorae flavescentis) is used to treat ulcerative colitis, tumors, and pruritus. Recently, phaseolin, formononetin, matrine, luteolin, and quercetin, through a network pharmacology approach, were tentatively identified as five bioactive constituents responsible for the anti-inflammatory effects of S. flavescentis. However, the role of phaseolin (one of the primary components of S. flavescentis) in the direct regulation of inflammation and inflammatory processes is not well known. In this study, the beneficial role of phaseolin against inflammation was explored in lipopolysaccharide (LPS)-induced inflammation models of RAW 264.7 macrophages and zebrafish larvae. Phaseolin inhibited LPS-mediated production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), without affecting cell viability. In addition, phaseolin suppressed pro-inflammatory mediators such as cyclooxygenase 2 (COX-2), interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and interleukin-6 (IL-6) in a dose-dependent manner. Furthermore, phaseolin reduced matrix metalloproteinase (MMP) activity as well as macrophage adhesion in vitro and the recruitment of leukocytes in vivo by downregulating Ninjurin 1 (Ninj1), an adhesion molecule. Finally, phaseolin inhibited the nuclear translocation of nuclear factor-kappa B (NF-κB). In view of the above, our results suggest that phaseolin could be a potential therapeutic candidate for the management of inflammation.

Download Full-text

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.

Download Full-text

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

Infection and Immunity ◽

10.1128/iai.73.5.2940-2950.2005 ◽

2005 ◽

Vol 73 (5) ◽

pp. 2940-2950 ◽

Cited By ~ 131

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.

Download Full-text

Anti-Inflammatory and Antioxidant Effects of Soroseris hirsuta Extract by regulating iNOS/NF-κB and NRF2/HO-1 Pathways in Murine Macrophage RAW 264.7 Cells

Applied Sciences ◽

10.3390/app11104711 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4711

Author(s):

Woo Jin Lee ◽

Wan Yi Li ◽

Sang Woo Lee ◽

Sung Keun Jung

Keyword(s):

Nitric Oxide ◽

Nuclear Translocation ◽

Antioxidant Properties ◽

Raw 264.7 Cells ◽

Heme Oxygenase 1 ◽

Raw 264.7 ◽

Related Factor ◽

Iκb Kinase ◽

Anti Inflammatory ◽

Antioxidant Effects

Until now, the physiological effects of Soroseris hirsuta were primarily unknown. Here we have evaluated the anti-inflammatory and antioxidant effects of Soroseris hirsuta extract (SHE) on lipopolysaccharide (LPS)-activated murine macrophages RAW 264.7 cells. SHE inhibited nitric oxide expression and inducible nitric oxide synthase expression in RAW 264.7 cells treated with LPS. Moreover, SHE suppressed LPS-induced phosphorylation of IκB kinase, inhibitor of kappa B, p65, p38, and c-JUN N-terminal kinase. Western blot and immunofluorescence analyses showed that SHE suppressed p65 nuclear translocation induced by LPS. Furthermore, SHE inhibited the reactive oxygen species in LPS-treated RAW 264.7 cells. SHE significantly increased heme oxygenase-1 expression and the nuclear translocation of nuclear factor erythroid 2-related factor 2. SHE suppressed LPS-induced interleukin-1β mRNA expression in RAW 264.7 cells. Thus, SHE is a promising nutraceutical as it displays anti-inflammatory and antioxidant properties.

Download Full-text