scholarly journals Selective unresponsiveness to the inhibition of p38 MAPK activation by cAMP helps L929 fibroblastoma cells escape TNF-α-induced cell death

2010 ◽  
Vol 9 (1) ◽  
pp. 6 ◽  
Author(s):  
Jing Wang ◽  
Ruihong Tang ◽  
Ming Lv ◽  
Jiyan Zhang ◽  
Beifen Shen
Keyword(s):  
Cell Death ◽  
P38 Mapk ◽  
Mapk Activation ◽  
Tnf Α

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 p38 MAP kinase inhibition ameliorates cisplatin nephrotoxicity in mice

2005 ◽  
Vol 289 (1) ◽  
pp. F166-F174 ◽  
Author(s):  
Ganesan Ramesh ◽  
W. Brian Reeves
Keyword(s):  
Renal Dysfunction ◽  
P38 Mapk ◽  
Renal Injury ◽  
Acute Renal Injury ◽  
Mapk Activation ◽  
Mapk Activity ◽  
Tnf Α

Cisplatin is an important chemotherapeutic agent but can cause acute renal injury. Part of this acute renal injury is mediated through tumor necrosis factor-α (TNF-α). The pathway through which cisplatin mediates the production of TNF-α and injury is not known. Cisplatin activates p38 MAPK and induces apoptosis in cancer cells. p38 MAPK activation leads to increased production of TNF-α in ischemic injury and in macrophages. However, little is known concerning the role of p38 MAPK in cisplatin-induced renal injury. Therefore, we examined the effect of cisplatin on p38 MAPK activity and the role of p38 MAPK in mediating cisplatin-induced TNF-α production and renal injury. In vitro, cisplatin caused a dose-dependent activation of p38 MAPK in proximal tubule cells. Inhibition of p38 MAPK activation led to inhibition of TNF-α production. In vivo, mice treated with a single dose of cisplatin (20 mg/kg body wt) developed severe renal dysfunction at 72 h [blood urea nitrogen (BUN): 154 ± 34 mg/dl, creatinine: 1.4 ± 0.4 mg/dl], which was accompanied by an increase in kidney p38 MAPK activity and an increase in infiltrating leukocytes. However, animals treated with the p38 MAPK inhibitor SKF-86002 along with cisplatin showed less renal dysfunction (BUN: 55 ± 14 mg/dl, creatinine: 0.3 ± 0.02 mg/dl, P < 0.05), less severe histological damage, and fewer leukocytes compared with cisplatin+vehicle-treated animals. Serum levels of TNF-α, sTNFRI, and sTNFRII also increased significantly in cisplatin-treated mice compared with SKF-86002-treated mice ( P < 0.05). Kidney mRNA levels of TNF-α were significantly increased in cisplatin-treated mice compared with either SKF-86002- or saline-treated animals. The hydroxyl radical scavenger DMTU (100 mg·kg body wt−1·day−1) prevented the activation of p38 MAPK by cisplatin both in vitro and in vivo. DMTU also completely prevented cisplatin-induced renal injury (BUN: 140 ± 27 vs. 22 ± 2 mg/dl, P < 0.005) and the increase in serum TNF-α (33 ± 7 vs. 4 ± 2 pg/ml, P < 0.005) and kidney TNF-α mRNA in vivo. We conclude that hydroxyl radicals, either directly or indirectly, activate p38 MAPK and that p38 MAPK plays an important role in mediating cisplatin-induced acute renal injury and inflammation, perhaps through production of TNF-α.

scholarly journals Differential induction of CD38 expression by TNF-α in asthmatic airway smooth muscle cells

2010 ◽  
Vol 299 (6) ◽  
pp. L879-L890 ◽  
Author(s):  
Joseph A. Jude ◽  
Julian Solway ◽  
Reynold A. Panettieri ◽  
Timothy F. Walseth ◽  
Mathur S. Kannan
Keyword(s):  
Smooth Muscle ◽  
P38 Mapk ◽  
Airway Smooth Muscle ◽  
Cyclase Activity ◽  
Mapk Activation ◽  
Cd38 Expression ◽  
Adp Ribosyl Cyclase ◽  
Tnf Α ◽  
Differential Induction ◽  
In Cells

The ADP-ribosyl cyclase activity of CD38, a membrane protein expressed in human airway smooth muscle (ASM) cells, generates cyclic ADP-ribose (cADPR), a Ca2+-mobilizing agent. cADPR-mediated Ca2+ responses to agonists are augmented in human ASM cells by TNF-α. CD38-deficient mice fail to develop airway hyperresponsiveness following intranasal TNF-α or IL-13 challenge, suggesting a role in asthma. The role of CD38 in human asthma remains unknown. We hypothesized that CD38 expression will be elevated in ASM cells from asthmatic donors (ASMA cells). CD38 mRNA and ADP-ribosyl cyclase activity were measured in cells maintained in growth-arrested conditions and exposed to vehicle or TNF-α (10–40 ng/ml). TNF-α-induced induction of CD38 expression was greater in ASMA than in ASM cells from nonasthmatic donors (ASMNA). In four of the six donors, basal and TNF-α-induced ERK and p38 MAPK activation were higher in ASMA than ASMNA cells. JNK MAPK activation was lower in ASMA than ASMNA cells. Nuclear NF-κB (p50 subunit) and phosphorylated c-Jun were comparable in cells from both groups, although nuclear c-Fos (part of the AP-1 complex) levels were lower in ASMA than ASMNA cells. NF-κB or AP-1 binding to their consensus sequences was comparable in ASMNA and ASMA cells, as are the decay kinetics of CD38 mRNA. The findings suggest that the differential induction of CD38 by TNF-α in ASMA cells is due to increased transcriptional regulation involving ERK and p38 MAPK activation and is independent of changes in NF-κB or AP-1 activation. The findings suggest a potential role for CD38 in the pathophysiology of asthma.

scholarly journals Cytokine Activation of p38 Mitogen-Activated Protein Kinase and Apoptosis Is Opposed by alpha-4 Targeting of Protein Phosphatase 2A for Site-Specific Dephosphorylation of MEK3

2007 ◽  
Vol 27 (12) ◽  
pp. 4217-4227 ◽  
Author(s):  
Todd D. Prickett ◽  
David L. Brautigan
Keyword(s):  
Protein Kinase ◽  
P38 Mapk ◽  
Protein Phosphatase ◽  
Protein Phosphatase 2A ◽  
Phosphorylation Site ◽  
Mitogen Activated Protein Kinase ◽  
Mapk Activation ◽  
Tnf Α ◽  
Mitogen Activated Protein ◽  
Phosphatase 2A

ABSTRACT alpha-4 is an essential gene and is a dominant antiapoptotic factor in various tissues that is a regulatory subunit for type 2A protein phosphatases. A multiplexed phosphorylation site screen revealed that knockdown of alpha-4 by small interfering RNA (siRNA) increased p38 mitogen-activated protein kinase (MAPK) and c-Jun phosphorylation without changes in JNK or ERK. FLAG-alpha-4 coprecipitated hemagglutinin-MEK3 plus endogenous protein phosphatase 2A (PP2A) and selectively enhanced dephosphorylation of Thr193, but not Ser189, in the activation loop of MEK3. Overexpression of alpha-4 suppressed p38 MAPK activation in response to tumor necrosis factor alpha (TNF-α). The alpha-4 dominant-negative domain (DND) (residues 220 to 340) associated with MEK3, but not PP2A, and its overexpression sensitized cells to activation of p38 MAPK by TNF-α and interleukin-1β, but not by ansiomycin or sorbitol. The response was diminished by nocodazole or by siRNA knockdown of the Opitz syndrome protein Mid1 that binds alpha-4 to microtubules. Interference by alpha-4 DND or alpha-4 siRNA increased caspase 3/7 activation in response to TNF-α. Growth of transformed cells in soft agar was enhanced by alpha-4 and suppressed by alpha-4 DND. The results show that alpha-4 targets PP2A activity to MEK3 to suppress p38 MAPK activation by cytokines, thereby inhibiting apoptosis and anoikis.

EGFR-independent activation of p38 MAPK and EGFR-dependent activation of ERK1/2 are required for ROS-induced renal cell death

2004 ◽  
Vol 287 (5) ◽  
pp. F1049-F1058 ◽  
Author(s):  
Jing Dong ◽  
Sampath Ramachandiran ◽  
Kulbhushan Tikoo ◽  
Zhe Jia ◽  
Serrine S. Lau ◽  
...  
Keyword(s):  
Cell Death ◽  
P38 Mapk ◽  
Egf Receptor ◽  
Histone H3 ◽  
Dominant Negative ◽  
Mapk Activation ◽  
Transfected Cells ◽  
H3 Phosphorylation ◽  
Hsp27 Phosphorylation ◽  
Histone H3 Phosphorylation

2,3,5-Tris-(glutathion- S-yl)hydroquinone (TGHQ), a reactive metabolite of the nephrotoxicant hydroquinone, induces the ROS-dependent activation of MAPKs, followed by histone H3 phosphorylation and oncotic cell death in renal proximal tubule epithelial cells (LLC-PK1). Cell death and histone H3 phosphorylation are attenuated by pharmacological inhibition of p38 MAPK or ERK1/2 pathways. Because TGHQ, but not epidermal growth factor (EGF), induces histone H3 phosphorylation and cell death in LLC-PK1 cells, we hypothesized that there are differences in the mechanisms by which TGHQ and EGF induce activation of the EGF receptor (EGFR). We therefore compared the relative ability of TGHQ, H2O2, and EGF to activate EGFR and MAPKs and found that p38 MAPK activation is EGFR independent, whereas ERK1/2 activation occurs mainly through EGFR activation. TGHQ, H2O2, and EGF induce different EGFR tyrosine phosphorylation profiles that likely influence the subsequent differential kinetics of MAPK activation. We next transfected LLC-PK1 cells with a dominant negative p38 MAPK-expressing plasmid (pcDNA3-DNp38). TGHQ failed to induce phosphorylation of p38 MAPK and its substrate, MK-2, in pcDNA3-DNp38-transfected cells, indicating loss of function of p38 MAPK. In untransfected, pcDNA3 or pcDNA3-p38 (native)-transfected LLC-PK1 cells, Hsp27 was intensively phosphorylated after TGHQ treatment, whereas in pcDNA3-DNp38-transfected cells, TGHQ failed to induce Hsp27 phosphorylation. Thus EGFR-independent p38 MAPK and EGFR-dependent ERK1/2 activation by TGHQ lead to the activation of two downstream signaling factors, i.e., histone H3 and Hsp27 phosphorylation, which have in common the potential ability to remodel chromatin.

scholarly journals KR-31378 Protects Cardiac H9c2 Cells from Chemical Hypoxia-Induced Cell Death via Inhibition of JNK/p38 MAPK Activation

2004 ◽  
Vol 54 (6) ◽  
pp. 575-583 ◽  
Author(s):  
Yong-Sam Jung ◽  
Dong-Ha Lee ◽  
Hong Lim ◽  
Kyu Yang Yi ◽  
Sung-Eun Yoo ◽  
...  
Keyword(s):  
Cell Death ◽  
P38 Mapk ◽  
H9c2 Cells ◽  
Mapk Activation ◽  
Chemical Hypoxia

scholarly journals Actinobacillus actinomycetemcomitans induces apoptosis in human monocytic THP-1 cells

2005 ◽  
Vol 54 (3) ◽  
pp. 293-298 ◽  
Author(s):  
Satsuki Kato ◽  
Norihiko Sugimura ◽  
Keisuke Nakashima ◽  
Tatsuji Nishihara ◽  
Yusuke Kowashi
Keyword(s):  
Cell Death ◽  
Cell Line ◽  
Dna Fragmentation ◽  
P38 Mapk ◽  
Immune Cells ◽  
Periodontal Diseases ◽  
Actinobacillus Actinomycetemcomitans ◽  
Mapk Activity ◽  
Tnf Α ◽  
Human Immune

It has previously been reported that the murine macrophage cell line J774.1 and the human oral epithelial cell line KB undergo apoptosis as a result of Actinobacillus actinomycetemcomitans infection. Recent studies have demonstrated that apoptosis regulation is modulated by multiple phosphorylation of several different protein kinases, including the major subtypes of the mitogen-activated protein kinase (MAPK) family. The MAPK family promotes cell survival and/or proliferation in response to growth factor stimulation, or apoptosis in response to various stress stimuli. The primary objective of the present investigation was to clarify whether human immune cells undergo apoptosis following A. actinomycetemcomitans infection and, if so, to establish the involvement of the MAPK family. Human monocytic THP-1 cells were infected with A. actinomycetemcomitans in microtubes. Lactate dehydrogenase release into the culture supernatant and DNA fragmentation in the cells were monitored. DNA fragmentation was also identified by agarose gel electrophoresis. Cell death following A. actinomycetemcomitans infection occurred by apoptosis, shown by an increase in the proportion of fragmented DNA and the typical ladder pattern of DNA fragmentation indicative of apoptosis. Furthermore, p38 MAPK activity and tumour necrosis factor alpha (TNF-α) levels increased following A. actinomycetemcomitans infection. In contrast, cell death and TNF-α levels in infected cells decreased upon addition of a p38 inhibitor or an anti-TNF-α antibody. However, exogenous TNF-α could not induce apoptosis in uninfected THP-1 cells. Interestingly, p38 MAPK activity diminished in the presence of anti-TNF-α antibody. These findings indicated that A. actinomycetemcomitans infection induces apoptosis in THP-1 cells and that p38 MAPK activity is directly involved in apoptosis. TNF-α may play an indirect role in apoptosis via enhanced p38 MAPK activity. A. actinomycetemcomitans-induced apoptosis of human immune cells may be important in terms of initiation and progression of periodontal diseases.

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