Anti-inflammatory Effect of Tolerance Induced by Pam3CSK4 in Murine Macrophage RAW 264.7 Cells via Inhibitor of NF-κB/MAPK Signaling Pathway

Yakhak Hoeji ◽  
2018 ◽  
Vol 62 (5) ◽  
pp. 306-312
Author(s):  
Sang-Chul Han ◽  
◽  
Na-Jin Kang ◽  
Kyungmin Park ◽  
Jiseon Park ◽  
...  
2018 ◽  
Vol 19 (7) ◽  
pp. 2027 ◽  
Author(s):  
Jingyu He ◽  
Xianyuan Lu ◽  
Ting Wei ◽  
Yaqian Dong ◽  
Zheng Cai ◽  
...  

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.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Gyeong-Eun Hong ◽  
Jin-A. Kim ◽  
Arulkumar Nagappan ◽  
Silvia Yumnam ◽  
Ho-Jeong Lee ◽  
...  

Scutellaria baicalensisGeorgi has been used as traditional medicine for treating inflammatory diseases, hepatitis, tumors, and diarrhea in Asia. Hence, we investigated the anti-inflammatory effect and determined the molecular mechanism of action of flavonoids isolated from KoreanS. baicalensisG. in lipopolysaccharide- (LPS-) stimulated RAW 264.7 macrophages. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to examine cytotoxicity of the flavonoids at various concentrations of 10, 40, 70, and 100 µg/mL. No cytotoxicity was observed in RAW 264.7 cells at these concentrations. Furthermore, the flavonoids decreased production of inflammatory mediators such as inducible nitric oxide synthase, cyclooxygenase-2, interleukin-6, and tumor necrosis factor-alpha and inhibited phosphorylation of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) in LPS-induced RAW 264.7 cells. Moreover, to identify the differentially expressed proteins in RAW 264.7 cells of the control, LPS-treated, and flavonoid-treated groups, two-dimensional gel electrophoresis and mass spectrometry were conducted. The identified proteins were involved in the inflammatory response and included PRKA anchor protein and heat shock protein 70 kD. These findings suggest that the flavonoids isolated fromS. baicalensisG. might have anti-inflammatory effects that regulate the expression of inflammatory mediators by inhibiting the NF-κB signaling pathway via the MAPK signaling pathway in RAW 264.7 cells.


2018 ◽  
Vol 43 (4) ◽  
pp. 375-384 ◽  
Author(s):  
Chang-Gu Hyun ◽  
Min-Jin Kim ◽  
Sang Suk Kim ◽  
Ji Hye Ko ◽  
Young Il Moon ◽  
...  

Abstract Objective In this study, we evaluated the anti-inflammatory effect of Shiranuhi flower in RAW 264.7 cells. Methods The effects of the extracts and solvent fractions on cell viability and LPS-induced inflammatory responses were investigated in RAW 264.7 cells. Results The results showed that the ethyl acetate fraction (HEF) significantly decreased NO production in RAW 264.7 cells; however, cell viability was not affected. In addition, ELISA assay revealed that HEF significantly inhibited the productions of PGE2, TNF-α, and IL-6. As well, using Western blot analysis, it was observed that HEF significantly reduced the expression levels of iNOS and COX-2 in a dose dependent manner. Furthermore, we detected a reduced phosphorylation of mitogen-activated protein kinases such as p38, JNK, and ERK1/2. This indicates that HEF regulates LPS-induced inflammatory responses, at least in part, via suppressing the MAPK signaling pathway. Correlation analysis also showed that anti-inflammatory activities were highly correlated to antioxidant activities in this study. Characterization of the Shiranuhi flowers for flavonoid contents using HPLC showed varied quantity of narirutin and hesperidin. Conclusion Overall, the results demonstrate that HEF may be a potential anti-inflammatory agent. In addition, our findings contribute to understanding the molecular mechanism underlying the anti-inflammatory effect of Shiranuhi flower.


1997 ◽  
Vol 17 (3) ◽  
pp. 1118-1128 ◽  
Author(s):  
C J Guthridge ◽  
D Eidlen ◽  
W P Arend ◽  
A Gutierrez-Hartmann ◽  
M F Smith

Lipopolysaccharide (LPS) treatment of monocytic cells has been shown to activate the Raf-1/mitogen-activated protein kinase (MAPK) signaling pathway and to increase secretory interleukin-1 receptor antagonist (sIL-1Ra) gene expression. The significance of the activation of the Raf-1/MAPK signaling pathway to LPS regulation of sIL-1Ra gene expression, however, has not been determined. This study addresses the role of the Raf-1/MAPK signaling pathway in regulation of sIL-1Ra gene expression by LPS. Cotransfection of the murine macrophage cell line RAW 264.7 with a 294-bp sIL-1Ra promoter/luciferase construct (pRA-294-luc) and a constitutively active Raf-1 kinase expression vector (pRSV-Raf-BXB) resulted in induction of sIL-1Ra promoter activity, indicating that Raf-1, like LPS, can regulate sIL-1Ra promoter activity. An in vitro MAPK analysis indicated that both LPS treatment and pRSV-Raf-BXB transfection of RAW 264.7 cells increases p42 MAPK activity. An in vitro Raf-1 kinase assay, however, failed to detect LPS-induced Raf-1 kinase activity in RAW 264.7 cells, suggesting that in RAW 264.7 cells, Raf-1 kinase is not an activating component of the LPS signaling pathway regulating MAPK activity or sIL-1Ra promoter activity. This observation was supported by results from transfection studies which demonstrated that expression of a dominant-inhibitory Raf-1 mutant in RAW 264.7 cells does not inhibit LPS-induced MAPK activity or sIL-1Ra promoter activity, indicating that LPS-induced sIL-1Ra promoter activation occurs independent of the Raf-1/MAPK signaling pathway. In additional studies, cotransfection of RAW 264.7 cells with pRA-294-luc and increasing amounts of pRSV-Raf-BXB caused a dose-dependent inhibition of LPS-induced sIL-1Ra promoter activity, indicating that the role of the Raf-1 pathway in the regulation of sIL-1Ra promoter activity by LPS is as an antagonizer. Interestingly, LPS treatment of RAW 264.7 cells, cotransfected with pRA-294-luc and pRSV-Raf-BXB, also inhibited pRSV-Raf-BXB-induced sIL-1Ra promoter activity, suggesting that inductions of sIL-1Ra promoter activity by LPS and Raf-1 actually occur by mutually antagonistic mechanisms. In support of this conclusion, sIL-1Ra promoter mapping studies indicated that LPS and Raf-1 responses localized to different regions of the sIL-1Ra promoter. Further studies demonstrated that mutual antagonism between the LPS and Raf-1 kinase pathways is not promoter specific, as the same phenomenon is observed in assays using a c-fos enhancer/thymidine kinase promoter/luciferase construct (pc-fos-TK81-luc). Additionally, mutual antagonism with regard to sIL-1Ra promoter activity also was observed between the LPS and MEK kinase pathways, indicating that mutual antagonism can occur in more than one MAPK activation pathway.


Sign in / Sign up

Export Citation Format

Share Document