TLR5-mediated activation of p38 MAPK regulates epithelial IL-8 expression via posttranscriptional mechanism

2003 ◽  
Vol 285 (2) ◽  
pp. G282-G290 ◽  
Author(s):  
Yimin Yu ◽  
Hui Zeng ◽  
Sean Lyons ◽  
Adam Carlson ◽  
Didier Merlin ◽  
...  
Keyword(s):  
P38 Mapk ◽  
Mrna Stability ◽  
Mrna Translation ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Maximal Inhibition ◽  
Mapk Activation ◽  
Intestinal Epithelia ◽  
Tnf Α ◽  
Sb 203580

Toll-like receptors (TLRs) activate antimicrobial gene expression in response to detection of specific bacterial products. Relatively little is known about TLR5, the only TLR thought to be preferentially expressed by epithelial cells, beyond that it confers activation of the transcription factor NF-κB in a MyD-88 dependent manner in response to flagellin. Because TLRs, in general, are also thought to signal through members of the MAPK family, we examined flagellin-induced MAPK activation (via examining its phosphorylation status) and its subsequent role in expression of the chemokine IL-8 in polarized intestinal epithelia. Flagellin, like other proinflammatory stimuli (TNF-α, Salmonella typhimurium), activated p38 MAPK in a TLR5-dependent manner, whereas aflagellate bacteria or EGF did not activate this kinase. Although ERK1 and -2 were also observed to be activated in response to flagellin, their activation was not restricted to proinflammatory stimuli because they were also potently activated by aflagellate bacteria ( S. typhimurium or Escherichia coli) and EGF (neither of which activate NF-κB in these cells). Pharmacological inhibition of p38 MAPK (by SB-203580) potently (IC50 = 10 nM) reduced expression of IL-8 protein (maximal inhibition, 75%) but had no effect on NF-κB activation, only slightly attenuated upregulation of IL-8 mRNA levels in response to flagellin, and did not effect IL-8 mRNA stability. Together, these results indicate that epithelial TLR5 mediates p38 activation and subsequently regulates flagellin-induced IL-8 expression independently of NF-κB, probably by influencing IL-8 mRNA translation.

scholarly journals Cigarette smoke and its component acrolein augment IL-8/CXCL8 mRNA stability via p38 MAPK/MK2 signaling in human pulmonary cells

2012 ◽  
Vol 303 (10) ◽  
pp. L929-L938 ◽  
Author(s):  
Nadia Moretto ◽  
Serena Bertolini ◽  
Claudia Iadicicco ◽  
Gessica Marchini ◽  
Manminder Kaur ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Cigarette Smoke ◽  
P38 Mapk ◽  
Mrna Stability ◽  
Airway Epithelial Cells ◽  
Transcriptional Level ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Pharmacological Inhibition ◽  
Pulmonary Cells

Interleukin-8 (IL-8/CXCL8) is an important neutrophil chemoattractant known to be elevated in the airways of cigarette smokers and in patients with chronic obstructive pulmonary disease (COPD). We examined the acute effect of aqueous cigarette smoke extract (CSE) on IL-8 expression in primary human pulmonary cells, in particular in normal human bronchial smooth muscle cells (HBSMCs). IL-8 mRNA levels increased upon CSE exposure in a concentration- and time-dependent manner, and such an effect was accompanied by IL-8 secretion. CSE-evoked elevation of IL-8 mRNA was mimicked by its component acrolein. Both CSE and acrolein induced p38 mitogen-activated protein kinase (MAPK) phosphorylation, accompanied by the phosphorylation of MAPK-activated kinase 2 (MK2), a known downstream substrate of the p38 MAPK, both in HBSMCs and in human airway epithelial cells. Furthermore, pharmacological inhibition of p38 MAPK or MK2 strongly accelerated the decay of IL-8 mRNA levels upon stimulation with CSE or acrolein and subsequent blockade of mRNA neosynthesis with actinomycin D in pulmonary structural cells (HBSMCs and airways epithelial cells) as well as in human alveolar macrophages. Conversely, pharmacological inhibition of ERK1/2 signaling inhibited CSE-induced steady-state levels of IL-8 mRNA without affecting mRNA stability, thus suggesting inhibition at the transcriptional level. In sum, p38 MAPK/MK2 signaling is an important posttranscriptional mechanism underlying upregulation of IL-8 mRNA levels elicited by CSE and acrolein. Given the pivotal role of IL-8 in neutrophil chemotaxis and activation, our results shed light on the mechanisms through which cigarette smoke can initiate inflammation in the lung.

TNF-α inhibits SP-A gene expression in lung epithelial cells via p38 MAPK

2002 ◽  
Vol 283 (2) ◽  
pp. L418-L427 ◽  
Author(s):  
Olga L. Miakotina ◽  
Jeanne M. Snyder
Keyword(s):  
Gene Expression ◽  
Epithelial Cells ◽  
P38 Mapk ◽  
Mapk Pathway ◽  
Lung Epithelial Cells ◽  
Mitogen Activated Protein Kinase ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Tnf Α ◽  
Lung Epithelial

Surfactant protein A (SP-A), the major lung surfactant-associated protein, mediates local defense against pathogens and modulates inflammation in the alveolus. Tumor necrosis factor (TNF)-α, a proinflammatory cytokine, inhibits SP-A gene expression in lung epithelial cells. Inhibitors of the phosphatidylinositol 3-kinase pathway, i.e., wortmannin, LY-294002, and rapamycin, did not block the inhibitory effects of TNF-α on SP-A mRNA levels. An inhibitor of the p44/42 mitogen-activated protein kinase (MAPK) pathway, PD-98059, was also ineffective. PD-169316 and SB-203580, inhibitors of p38 MAPK, blocked the TNF-α-mediated inhibition of SP-A mRNA levels. TNF-α increased the phosphorylation of p38 MAPK within 15 min. Anisomycin, an activator of p38 MAPK, increased p38 MAPK phosphorylation and decreased SP-A mRNA levels in a dose-dependent manner. Finally, TNF-α increased the phosphorylation of ATF-2, a transcription factor that is a p38 MAPK substrate. We conclude that TNF-α downregulates SP-A gene expression in lung epithelial cells via the p38 MAPK signal transduction pathway.

Acute adenosine preconditioning is mediated by p38 MAPK activation in discrete subcellular compartments

2005 ◽  
Vol 288 (3) ◽  
pp. H1359-H1366 ◽  
Author(s):  
Cherry Ballard-Croft ◽  
Gentian Kristo ◽  
Yukihiro Yoshimura ◽  
Easton Reid ◽  
Byron J. Keith ◽  
...  
Keyword(s):  
P38 Mapk ◽  
Adenosine Receptor ◽  
Ischemia Reperfusion ◽  
Mitochondrial Fraction ◽  
Control Group ◽  
Mapk Activation ◽  
Subcellular Compartments ◽  
Sb 203580

Although acute adenosine preconditioning (PC) is well established, the signaling pathways mediating this cardioprotection remain unclear. Because adenosine receptor agonists activate p38 MAPK and this kinase has been implicated in ischemic and pharmacological PC, the purpose of this study was to determine the role of p38 MAPK in acute adenosine receptor PC. The role of p38 MAPK activation in discrete subcellular compartments during ischemia-reperfusion was also determined. The following groups were used in an in vivo rat ischemia-reperfusion model: 1) control (10% DMSO iv), 2) the A1/A2a adenosine receptor AMP-579 (50 μg/kg iv), 3) AMP-579 + the A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 100 μg/kg iv), 4) AMP-579 + the p38 MAPK inhibitor SB-203580 (1 mg/kg iv), and 5) SB-203580 alone. p38 MAPK activation was measured by Western blot analysis in cytosolic, mitochondrial, membrane, and nuclear/myofilament fractions obtained from hearts at preischemic, ischemic, and reperfusion time points. A significant reduction in infarct size was observed with AMP-579 PC, an effect blocked by DPCPX or SB-203580 pretreatment. AMP-579 treatment was associated with a significant increase in p38 MAPK activation in the nuclear/myofilament fraction before ischemia, whereas no activation of this kinase occurred during ischemia or reperfusion. In contrast, p38 MAPK was activated in the mitochondrial fraction by ischemia and in the cytosolic, mitochondrial, and membrane fractions by reperfusion in the control group. SB-203580 blocked the AMP-579-induced increase in phosphorylation of the downstream p38 substrate activating transcription factor-2. These results suggest a role for p38 MAPK activation in discrete subcellular compartments in acute adenosine A1 receptor PC.

scholarly journals Differential Activation of Innate Immune Responses by Adenovirus and Adeno-Associated Virus Vectors

2002 ◽  
Vol 76 (9) ◽  
pp. 4580-4590 ◽  
Author(s):  
Anne-Kathrin Zaiss ◽  
Qiang Liu ◽  
Gloria P. Bowen ◽  
Norman C. W. Wong ◽  
Jeffrey S. Bartlett ◽  
...  
Keyword(s):  
Immune System ◽  
Intravenous Administration ◽  
Innate Immune System ◽  
Innate Immune ◽  
Target Cells ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Adeno Associated Virus ◽  
Tnf Α ◽  
Adenovirus Vectors

ABSTRACT Adenovirus vectors induce acute inflammation of infected tissues due to activation of the innate immune system and expression of numerous chemokines and cytokines in transduced target cells. In contrast, adeno-associated virus (AAV) vectors are not associated with significant inflammation experimentally or clinically. We tested the ability of AAV vectors to induce the expression of chemokines in vitro and to activate the innate immune system in vivo. In human HeLa cells and murine renal epithelium-derived cells (REC cells) the adenovirus vector AdlacZ induced the expression of multiple inflammatory chemokines including RANTES, interferon-inducible protein 10 (IP-10), interleukin-8 (IL-8), MIP-1β, and MIP-2 in a dose-dependent manner. The use of AAVlacZ did not induce the expression of these chemokines above baseline levels despite 40-fold-greater titers than AdlacZ and greater amounts of intracellular AAVlacZ genomes according to Southern and slot blot analysis. This finding confirmed that the lack of AAVlacZ induction of chemokine was not due to reduced transduction. In DBA/2 mice, the intravenous administration of 2.5 × 1011 particles of AAVlacZ resulted in the rapid induction of liver tumor necrosis factor alpha (TNF-α), RANTES, IP-10, MIP-1β, MCP-1, and MIP-2 mRNAs. However, 6 h following injection, chemokine mRNA levels returned to baseline. As expected, administration of 10-fold less AdlacZ caused an induction of liver TNF-α and chemokine mRNAs that persisted for more than 24 h posttransduction. Whereas intravenous administration of 2.5 × 1011 particles of AAVlacZ triggered a transient infiltration of neutrophils and CD11b+ cells into liver, this response stood in contrast to widespread inflammation and toxicity induced by AdlacZ. Kupffer cell depletion abolished AAVlacZ but not AdlacZ-induced chemokine expression and neutrophil infiltration. In summary, these results show that AAV vectors activate the innate immune system to a lesser extent than do adenovirus vectors and offer a possible explanation for the reduced inflammatory properties of AAV compared to adenovirus vectors.

Corydalis Saxicola Bunting Total Alkaloids Inhibits Paclitaxel-Induced Peripheral Neuropathy By Regulating PKCε-TRPV1 and p38 MAPK-TRPV1 Signaling Pathways

2021 ◽  
Author(s):  
chu xue ◽  
Si-Xue Liu ◽  
Jie Hu ◽  
Jin Huang ◽  
Hong-Min Liu ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Peripheral Neuropathy ◽  
Protein Expression ◽  
Signaling Pathways ◽  
P38 Mapk ◽  
Cell Model ◽  
Mrna Levels ◽  
Drg Neurons ◽  
Total Alkaloids ◽  
Tnf Α

Abstract Background: Corydalis saxicola Bunting, a traditional Chinese medicine, has been proven to work well in anti-inflammation, blood circulation improvement, hemostasis, analgesia. This study was designed to observe the effects and potential mechanism of Corydalis saxicola Bunting total alkaloids (CSBTA) on paclitaxel-induced peripheral neuropathy (PIPN). Materials and methods: Following 4 times intraperitoneal injections of paclitaxel (2 mg/kg) and intragastrically (i.g.) administrated at 30 or 120 mg/kg CSBTA, mechanical and thermal allodynia and hyperalgesia in rats were tested. After 40 days, serum was collected for the detection of PGE2, TNF-α, and IL-1β by ELISA. The L4-L6 segment spinal cord, DRG, and plantar skin were harvested, and protein and gene expression of CGRP, SP, TRPV1, p38, and PKCε were analyzed by Western-blot or RT-qPCR. Parallelly, the PIPN cell model was also established in primary DRG neurons by paclitaxel stimulation (300 nM, 5 d). We examined PGE2, TNF-α and CGRP mRNA levels, and the protein expression on the PKCε-TRPV1 and p38 MAPK-TRPV1 pathways in PIPN cell model with or without CSBTA (25 μg/ml and 50 μg/ml). Results: The results showed that CSBTA effectively ameliorated allodynia and hyperalgesia in PIPN rats, regulated the contents of cytokines and neuropeptides in different tissues and cell models. CSBTA significantly decreased the protein expression of PKCε-TRPV1 and p38 MAPK-TRPV1 signaling pathways in the spinal cord and DRG tissues in the PIPN animal model and primary DRG neurons. Conclusion: Therefore, CSBTA has a perspective therapeutic effect on the treatment of paclitaxel-induced peripheral neuropathy.

Acute p38 MAPK activation decreases force development in ventricular myocytes

2003 ◽  
Vol 285 (6) ◽  
pp. H2578-H2586 ◽  
Author(s):  
Yi Chen ◽  
Ravi Rajashree ◽  
Qinghang Liu ◽  
Polly Hofmann
Keyword(s):  
Protein Kinase ◽  
P38 Mapk ◽  
Ventricular Myocytes ◽  
Fold Increase ◽  
Isometric Tension ◽  
Mitogen Activated Protein Kinase ◽  
Independent Manner ◽  
Mapk Activation ◽  
Force Development ◽  
Sb 203580

Evidence suggests that p38 mitogen-activated protein kinase (MAPK) activation influences cardiac function on an acute basis. The characterization and mechanisms by which this occurs were investigated in the present study. Adult rat ventricular myocytes treated with 1 mM arsenite for 30 min had a 16-fold increase in p38 MAPK phosphorylation that was attenuated by SB-203580 (a p38 MAPK inhibitor). Extracellular signal-regulated protein kinase (ERK) and c-Jun NH2-terminal kinase (JNK) were also minimally activated, but this activation was not sensitive to SB-203580. In addition, arsenite caused a p38 MAPK-independent translocation/activation of protein phosphatase 2a (PP2a) and decrease in phosphorylation of myosin light chain 2 (LC2). Arsenite-p38 MAPK activation led to translocation of heat shock protein 27 but not αB-crystallin to the myofilaments. Using isolated cardiomyocytes, we determined that arsenite reduces isometric tension without a change in Ca2+ sensitivity of tension via p38 MAPK and lowers myofibrillar actomyosin Mg2+-ATPase activity in a p38 MAPK-independent manner. Thus arsenite induces a p38 MAPK-independent change in PP2a and LC2 that may account for the arsenite-dependent decrease in ATPase and a p38 MAPK-dependent modification of the myofilaments that decreases myocardial force development.

p38 MAPK and NF-κB mediate COX-2 expression in human airway myocytes

2003 ◽  
Vol 285 (5) ◽  
pp. L1087-L1098 ◽  
Author(s):  
Cherie A. Singer ◽  
Kimberly J. Baker ◽  
Alan McCaffrey ◽  
David P. AuCoin ◽  
Melissa A. Dechert ◽  
...  
Keyword(s):  
P38 Mapk ◽  
Binding Activity ◽  
Dependent Manner ◽  
Human Airway ◽  
Mitogen Activated Protein ◽  
Steady State Levels ◽  
Cox 2 ◽  
P38 Mapk Inhibitor ◽  
Factor Α ◽  
Sb 203580

We have previously demonstrated that p38 and extracellular signal-regulated protein kinase (ERK) mitogen-activated protein kinases (MAPK) are components of proinflammatory induced cytokine expression in human airway myocytes. The experiments described here further these studies by examining p38 MAPK and NF-κB regulation of cyclooxygenase-2 (COX-2) expression in response to a complex inflammatory stimulus consisting of 10 ng/ml interleukin (IL)-1β, tumor necrosis factor-α (TNF-α), and interferon (IFN)-γ. COX-2 expression was induced with this stimulus in a time-dependent manner, with maximal expression seen 12-20 h after treatment. Semiquantitative RT-PCR and immunoblotting experiments demonstrate decreased COX-2 expression following treatment with the p38 MAPK inhibitor SB-203580 (25 μM) or the proteosome inhibitor MG-132 (1 μM). SB-203580 did not affect cytokine-stimulated IκBα degradation, NF-κB nuclear binding activity, or NF-κB-dependent signaling from the COX-2 promoter, indicating that p38 MAPK and NF-κB may affect COX-2 expression via separate signaling pathways. SB-203580, but not MG-132, also increased the initial rate of COX-2 mRNA decay, indicating p38 MAPK, but not NF-κB, participates in the regulation of COX-2 mRNA stability. These findings suggest that although p38 MAPK and NF-κB signaling regulate steady-state levels of COX-2 expression, p38 MAPK additionally affects stability of COX-2 mRNA in cytokine-stimulated human airway myocytes.

scholarly journals Protective effect of Cordyceps sinensis extract on lipopolysaccharide-induced acute lung injury in mice

2019 ◽  
Vol 39 (6) ◽  
Author(s):  
Shuiqiao Fu ◽  
Weina Lu ◽  
Wenqiao Yu ◽  
Jun Hu
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Protective Effect ◽  
Weight Ratio ◽  
Cordyceps Sinensis ◽  
Myeloperoxidase Activity ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Tnf Α ◽  
Cox 2

Abstract Background: To study the protective effect of Cordyceps sinensis extract (Dong Chong Xia Cao in Chinese [DCXC]) on experimental acute lung injury (ALI) mice. Methods and results: ALI model was induced by intratracheal-instilled lipopolysaccharide (LPS, 2.4 mg/kg) in BALB/c male mice. The mice were administrated DCXC (ig, 10, 30, 60 mg/kg) in 4 and 8 h after receiving LPS. Histopathological section, wet/dry lung weight ratio and myeloperoxidase activity were detected. Bronchoalveolar lavage fluid (BALF) was collected for cell count, the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and nitric oxide (NO) in BALF was detected by ELISA, the protein and mRNA expression of nuclear factor-κB p65 (NF-κB p65), inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in lung tissue was detected by Western blot and RT-PCR. The result showed that DCXC could reduce the degree of histopathological injury, wet/dry weight ratio (W/D ratio) and myeloperoxidase activity (P<0.05) with a dose-dependent manner. The increased number of total cells, neutrophils and macrophages in BALF were significantly inhibited by DCXC treatment (P<0.05). The increased levels of TNF-α, IL-1β, IL-6 and NO in BALF after LPS administration was significantly reduced by DCXC (P<0.05). In addition, the increased protein and mRNA levels of iNOS, COX-2 and NF-κB p65 DNA binding ability in LPS group were dose-dependently reduced by DCXC treatment (P<0.05). Conclusion: DCXC could play an anti-inflammatory and antioxidant effect on LPS-induced ALI through inhibiting NF-κB p65 phosphorylation, and the expression of COX-2 and iNOS in lung. The result showed that DCXC has a potential protective effect on the ALI.

scholarly journals TNF-α-Induced NF-κB Activation Stimulates Skeletal Muscle Glycolytic Metabolism Through Activation of HIF-1α

Endocrinology ◽  
2015 ◽  
Vol 156 (5) ◽  
pp. 1770-1781 ◽  
Author(s):  
A. H. V. Remels ◽  
H. R. Gosker ◽  
K. J. P. Verhees ◽  
R. C. J. Langen ◽  
A. M. W. J. Schols
Keyword(s):  
Oxidative Metabolism ◽  
Lactate Production ◽  
Quadriceps Muscle ◽  
Metabolic Adaptation ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Glycolytic Metabolism ◽  
Consistent Finding ◽  
Tnf Α ◽  
Muscle Biopsies

A shift in quadriceps muscle metabolic profile toward decreased oxidative metabolism and increased glycolysis is a consistent finding in chronic obstructive pulmonary disease (COPD). Chronic inflammation has been proposed as a trigger of this pathological metabolic adaptation. Indeed, the proinflammatory cytokine TNF-α impairs muscle oxidative metabolism through activation of the nuclear factor-κB (NF-κB) pathway. Putative effects on muscle glycolysis, however, are unclear. We hypothesized that TNF-α-induced NF-κB signaling stimulates muscle glycolytic metabolism through activation of the glycolytic regulator hypoxia-inducible factor-1α (HIF-1α). Wild-type C2C12 and C2C12-IκBα-SR (blocked NF-κB signaling) myotubes were stimulated with TNF-α, and its effects on glycolytic metabolism and involvement of the HIF pathway herein were investigated. As proof of principle, expression of HIF signaling constituents was investigated in quadriceps muscle biopsies of a previously well-characterized cohort of clinically stable patients with severe COPD and healthy matched controls. TNF-α increased myotube glucose uptake and lactate production and enhanced the activity and expression levels of multiple effectors of muscle glycolytic metabolism in a NF-κB-dependent manner. In addition, TNF-α activated HIF signaling, which required classical NF-κB activation. Moreover, the knockdown of HIF-1α largely attenuated TNF-α-induced increases in glycolytic metabolism. Accordingly, the mRNA levels of HIF-1α and the HIF-1α target gene, vascular endothelial growth factor (VEGF), were increased in muscle biopsies of COPD patients compared with controls, which was most pronounced in the patients with high levels of muscle TNF-α. In conclusion, these data show that TNF-α-induced classical NF-κB activation enhances muscle glycolytic metabolism in a HIF-1α-dependent manner.

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