scholarly journals Frutescone O from Baeckea frutescens Blocked TLR4-Mediated Myd88/NF-κB and MAPK Signaling Pathways in LPS Induced RAW264.7 Macrophages

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiaobing Lin ◽  
Junhan Zhang ◽  
Decai Fan ◽  
Jiqin Hou ◽  
Hao Wang ◽  
...  

Frutescone O was isolated from the aerial parts of Baeckea frutescens L., which was commonly used as a folk medicinal material for treating anti-inflammatory disease in South East Asia. This study aimed to investigate the anti-inflammatory activity and related signaling cascade of Frutescone O (Fru) in LPS induced RAW264.7 cells. The anti-inflammation activity of Frutescone O was determined according to the inhibitory effects on the secretion of nitric oxide (NO), expression of inducible NO synthase, and pro-inflammatory cytokines. The regulation of Myeloid differentiation factor 88 (Myd88), inhibition of NF-κB, and MAPK pathways were further investigated for molecular mechanisms. Fru significantly decreased the expression of iNOS and the production of NO in LPS-stimulated RAW264.7 cells. It also dose-dependently suppressed LPS induced expression of IL-1β, IL-6, and TNF-α. Furthermore, Fru remarkably inhibited the upregulation of NF-κB (p50) expression in the nucleus and the phosphorylation ratio of p38, JNK, ERK, and Myd88 signaling protein. The molecular docking and cellular thermal shift assay (CETSA) results indicated that Fru participated in a robust and stable interaction with the active site of TLR4-MD2. Thus, Fru suppressed the LPS induced inflammation in RAW264.7 cells by blocking the TLR4 mediated signal transduction through the NF-κB and MAPK signaling pathways and inhibiting the Myd88 and iNOS expression.

2019 ◽  
Vol 86 (2) ◽  
pp. 171-176 ◽  
Author(s):  
Chenxu Zhao ◽  
Yazhou Wang ◽  
Xue Yuan ◽  
Guoquan Sun ◽  
Bingyu Shen ◽  
...  

AbstractSubacute ruminal acidosis (SARA) can increase the level of inflammation and induce rumenitis in dairy cows. Berberine (BBR) is the major active component of Rhizoma Coptidis, which is a type of Chinese anti-inflammatory drug for gastrointestinal diseases. The purpose of this study was to investigate the anti-inflammatory effects of BBR on lipopolysaccharide (LPS)-stimulated rumen epithelial cells (REC) and the underlying molecular mechanisms. REC were cultured and stimulated with LPS in the presence or absence of different concentrations of BBR. The results showed that cell viability was not affected by BBR. Moreover, BBR markedly decreased the concentrations and mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, and interleukin-6 in the LPS-treated REC in a dose-dependent manner. Importantly, Western blotting analysis showed that BBR significantly suppressed the protein expression of toll-like receptor 4 (TLR4) and myeloid differentiation primary response protein (MyD88) and the phosphorylation of nuclear factor-κB (NF-κB), inhibitory kappa B (IκBα), p38 mitogen-activated protein kinase (MAPK), and c-Jun N-terminal kinase (JNK) in LPS-treated REC. Furthermore, the results of immunocytofluorescence showed that BBR significantly inhibited the nuclear translocation of NF-κB p65 induced by LPS treatment. In conclusion, the protective effects of BBR on LPS-induced inflammatory responses in REC may be due to its ability to suppress the TLR4-mediated NF-κB and MAPK signaling pathways. These findings suggest that BBR can be used as an anti-inflammatory drug to treat inflammation induced by SARA.


Author(s):  
Eun Suk Son ◽  
Jeong-Wooung Park ◽  
Hye Ran Park ◽  
Woorijarang Han ◽  
Dae Eun Yun ◽  
...  

Citrus peel has been used in Asian traditional medicine for the treatment of cough, asthma, and bronchial disorders. However, the anti-inflammatory effect of quercetogetin (QUE), a polymethoxylated flavone isolated from the peel of citrus unshui is poorly understood. We investigated the anti-inflammatory effect and the molecular mechanisms of QUE in lipopolysaccharide (LPS)-induced RAW264.7 cells. QUE inhibited the production of NO and prostaglandin E2 by suppressing the LPS-induced expression of inducible nitric oxide synthase and cyclooxygenase-2 at both the mRNA and protein levels. QUE suppressed the production of proinflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α. QUE also inhibited the translocation of the nuclear factor kappa B subunit, p65, into the nucleus by interrupting the phosphorylation of IκB-α in LPS-induced RAW 264.7 cells. Based on the finding that QUE significantly decreased p-ERK protein expression in LPS-induced RAW264.7 cells, we confirmed that suppression of the inflammatory process by QUE was mediated through the MAPK pathway. This is the first report on the strong anti-inflammatory effects of QUE, which is a compound that can potentially be used as a therapeutic agent for inflammatory diseases.


2021 ◽  
Author(s):  
Mengyue Tian ◽  
Ke Li ◽  
Ruonan Liu ◽  
Jinliang Du ◽  
Dongmin Zou ◽  
...  

Abstract Background: Laminitis, an inflammation of the claw laminae, is one of the major causes of bovine lameness, which can lead to enormous economic losses and animal welfare problems in dairy farms. Angelica polysaccharide (AP) is proved to possess anti-inflammatory properties. But the role of AP on inflammatory response of the claw dermal cells has not been reported. The aim of this study was to investigate the anti-inflammatory effects of AP on lipopolysaccharide (LPS)-induced primary claw dermal cells of dairy cow and clarify the potential mechanisms. In the current research, the primary claw dermal cells were exposed to gradient concentrations of AP (10, 50, 100 µg/mL) in the presence of 10 µg/mL LPS. The levels of cytokines and nitric oxide (NO) were detected with ELISA and Griess colorimetric method. The mRNA expressions of TLR4, MyD88 and chemokines were measured with qPCR. The activation of NF-κB and MAPK signaling pathways was detected with western blotting.Results: The results indicated that AP reduced the production of inflammatory mediators (TNF-α, IL-1β, IL-6 and NO), downregulated the mRNA expression of TLR4, MyD88 and some pro-inflammatory chemokines (CCL2, CCL20, CXCL2, CXCL8, CXCL10), and suppressed the NF-κB and MAPK signaling pathways evidenced by inhibition of the phosphorylation of IκBα, p65 and ERK, JNK, p38.Conclusions: Our results demonstrated that AP may exert its anti-inflammatory effects on claw dermal cells of dairy cow by regulating the NF-κB and MAPK signaling pathways.


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.


Nutrients ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 533 ◽  
Author(s):  
Hee-Soo Han ◽  
Ji-Sun Shin ◽  
Da-Bin Myung ◽  
Hye Ahn ◽  
Sun Lee ◽  
...  

Skin photoaging is mainly caused by exposure to ultraviolet (UV) light, which increases expressions of matrix metalloproteinases (MMPs) and destroys collagen fibers, consequently inducing wrinkle formation. Nutritional factors have received scientific attention for use as agents for normal skin functions. The aim of this study was to investigate the effect of hot water extracts from the leaves of Hydrangea serrata (Thunb.) Ser. (WHS) against ultraviolet B (UVB)-induced skin photoaging and to elucidate the underlying molecular mechanisms in human foreskin fibroblasts (Hs68) and HR-1 hairless mice. WHS recovered UVB-reduced cell viability and ameliorated oxidative stress by inhibiting intracellular reactive oxygen species (ROS) generation in Hs68 cells. WHS rescued UVB-induced collagen degradation by suppressing MMP expression, and reduced the mRNA levels of inflammatory cytokines. These anti-photoaging activities of WHS were associated with inhibition of the activator protein 1 (AP-1), signal transduction and activation of transcription 1 (STAT1), and mitogen-activated protein kinase (MAPK) signaling pathways. Oral administration of WHS effectively alleviated dorsal skin from wrinkle formation, epidermal thickening, collagen degradation, and skin dehydration in HR-1 hairless mice exposed to UVB. Notably, WHS suppressed UVB activation of the AP-1 and MAPK signaling pathways in dorsal mouse skin tissues. Taken together, our data indicate that WHS prevents UVB-induced skin damage due to collagen degradation and MMP activation via inactivation of MAPK/AP-1 signaling pathway.


Sign in / Sign up

Export Citation Format

Share Document