Role of p38 mitogen-activated protein kinase pathway in estrogen-mediated cardioprotection following trauma-hemorrhage

2007 ◽  
Vol 292 (6) ◽  
pp. H2982-H2987 ◽  
Author(s):  
Jun-Te Hsu ◽  
Ya-Ching Hsieh ◽  
Wen Hong Kan ◽  
Jian Guo Chen ◽  
Mashkoor A. Choudhry ◽  
...  

p38 mitogen-activated protein kinase (MAPK) activates a number of heat shock proteins (HSPs), including HSP27 and αB-crystallin, in response to stress. Activation of HSP27 or αB-crystallin is known to protect organs/cells by increasing the stability of actin microfilaments. Although our previous studies showed that 17β-estradiol (E2) improves cardiovascular function after trauma-hemorrhage, whether the salutary effects of E2 under those conditions are mediated via p38 MAPK remains unknown. Male rats (275–325 g body wt) were subjected to soft tissue trauma and hemorrhage (35–40 mmHg mean blood pressure for ∼90 min) followed by fluid resuscitation. At the onset of resuscitation, rats were injected intravenously with vehicle, E2 (1 mg/kg body wt), E2 + the p38 MAPK inhibitor SB-203580 (2 mg/kg body wt), or SB-203580 alone, and various parameters were measured 2 h thereafter. Cardiac functions that were depressed after trauma-hemorrhage were returned to normal levels by E2 administration, and phosphorylation of cardiac p38 MAPK, HSP27, and αB-crystallin was increased. The E2-mediated improvement of cardiac function and increase in p38 MAPK, HSP27, and αB-crystallin phosphorylation were abolished with coadministration of SB-203580. These results suggest that the salutary effect of E2 on cardiac function after trauma-hemorrhage is in part mediated via upregulation of p38 MAPK and subsequent phosphorylation of HSP27 and αB-crystallin.

2003 ◽  
Vol 284 (2) ◽  
pp. C339-C348 ◽  
Author(s):  
Stephen J. Keely ◽  
Kim E. Barrett

We have previously shown that Ca2+-dependent Cl−secretion across intestinal epithelial cells is limited by a signaling pathway involving transactivation of the epidermal growth factor receptor (EGFR) and activation of ERK mitogen-activated protein kinase (MAPK). Here, we have investigated a possible role for p38 MAPK in regulation of Ca2+-dependent Cl− secretion. Western blot analysis of T84 colonic epithelial cells revealed that the muscarinic agonist carbachol (CCh; 100 μM) stimulated phosphorylation and activation of p38 MAPK. The p38 inhibitor SB-203580 (10 μM) potentiated and prolonged short-circuit current ( I sc) responses to CCh across voltage-clamped T84 cells to 157.4 ± 6.9% of those in control cells ( n = 21; P < 0.001). CCh-induced p38 phosphorylation was attenuated by the EGFR inhibitor tyrphostin AG-1478 (0.1 nM–10 μM) and by the Src family kinase inhibitor PP2 (20 nM–2 μM). The effects of CCh on p38 phosphorylation were mimicked by thapsigargin (TG; 2 μM), which specifically elevates intracellular Ca2+, and were abolished by the Ca2+ chelator BAPTA-AM (20 μM), implying a role for intracellular Ca2+ in mediating p38 activation. SB-203580 (10 μM) potentiated I sc responses to TG to 172.4 ± 18.1% of those in control cells ( n= 18; P < 0.001). When cells were pretreated with SB-203580 and PD-98059 to simultaneously inhibit p38 and ERK MAPKs, respectively, I sc responses to TG and CCh were significantly greater than those observed with either inhibitor alone. We conclude that Ca2+-dependent agonists stimulate p38 MAPK in T84 cells by a mechanism involving intracellular Ca2+, Src family kinases, and the EGFR. CCh-stimulated p38 activation constitutes a similar, but distinct and complementary, antisecretory signaling pathway to that of ERK MAPK.


2002 ◽  
Vol 283 (5) ◽  
pp. L1094-L1102 ◽  
Author(s):  
Wen Ning ◽  
Ruiping Song ◽  
Chaojun Li ◽  
Edward Park ◽  
Amir Mohsenin ◽  
...  

In lung injury and progressive lung diseases, the multifunctional cytokine transforming growth factor-β1 (TGF-β1) modulates inflammatory responses and wound repair. Heme oxygenase-1 (HO-1) is a stress-inducible protein that has been demonstrated to confer cytoprotection against oxidative injury and provide a vital function in maintaining tissue homeostasis. Here we report that TGF-β1 is a potent inducer of HO-1 and examined the signaling pathway by which TGF-β1 regulates HO-1 expression in human lung epithelial cells (A549). TGF-β1(1–5 ng/ml) treatment resulted in a marked time-dependent induction of HO-1 mRNA in A549 cells, followed by corresponding increases in HO-1 protein and HO enzymatic activity. Actinomycin D and cycloheximide inhibited TGF-β1-responsive HO-1 mRNA expression, indicating a requirement for transcription and de novo protein synthesis. Furthermore, TGF-β1 rapidly activated the p38 mitogen-activated protein kinase (p38 MAPK) pathway in A549 cells. A chemical inhibitor of p38 MAPK (SB-203580) abolished TGF-β1-inducible HO-1 mRNA expression. Both SB-203580 and expression of a dominant-negative mutant of p38 MAPK inhibited TGF-β1-induced ho-1 gene activation, as assayed by luciferase activity of an ho-1enhancer/luciferase fusion construct (pMHO1luc-33+SX2). These studies demonstrate the critical intermediacy of the p38 MAPK pathway in the regulation of HO-1 expression by TGF-β1.


2002 ◽  
Vol 283 (3) ◽  
pp. H941-H948 ◽  
Author(s):  
Kouseki Hirade ◽  
Osamu Kozawa ◽  
Kumiko Tanabe ◽  
Masayuki Niwa ◽  
Hiroyuki Matsuno ◽  
...  

We investigated the effects of thrombin on the induction of heat shock proteins (HSP) 70 and 27, and the mechanism behind the induction in aortic smooth muscle A10 cells. Thrombin increased the level of HSP27 but had little effect on the level of HSP70. Thrombin stimulated the accumulation of HSP27 dose dependently between 0.01 and 1 U/ml and cycloheximide reduced the accumulation. Thrombin stimulated an increase in the level of HSP27 mRNA and actinomycin D suppressed the thrombin-increased mRNA level. Thrombin induced the phosphorylation of p38 mitogen-activated protein kinase (MAPK). The HSP27 accumulation by thrombin was reduced by SB-203580 and PD-169316 but not by SB-202474. SB-203580 and PD-169316 suppressed the thrombin-induced phosphorylation of p38 MAPK. SB-203580 reduced the thrombin-increased level of HSP27 mRNA. Dissociation of the aggregated HSP27 to the dissociated HSP27 was induced by thrombin. Dissociation was inhibited by SB-203580. Thrombin induced the phosphorylation of HSP27 and the phosphorylation was suppressed by SB-203580. These results indicate that thrombin stimulates not only the dissociation of HSP27 but also the induction of HSP27 via p38 MAPK activation in aortic smooth muscle cells.


2000 ◽  
Vol 113 (2) ◽  
pp. 227-235 ◽  
Author(s):  
N. Johansson ◽  
R. Ala-aho ◽  
V. Uitto ◽  
R. Grenman ◽  
N.E. Fusenig ◽  
...  

Collagenase-3 (MMP-13) is a human matrix metalloproteinase specifically expressed by transformed squamous epithelial cells, i.e. squamous cell carcinoma (SCC) cells in culture and in vivo. Here, we have elucidated the signaling pathways regulating MMP-13 expression in transformed human epidermal keratinocytes, i.e. ras-transformed HaCaT cell line A-5 and cutaneous SCC cell line (UT-SCC-7). Treatment with tumor necrosis factor-(alpha) (TNF-(alpha) resulted in activation of extracellular signal-regulated kinase (ERK)1,2, Jun N-terminal kinase and p38 mitogen-activated protein kinase (MAPK) in both cell lines. In addition, transforming growth factor-(beta) (TGF-(beta) activated p38 MAPK in both cell lines, and ERK2 in A-5 cells. Selective inhibition of p38 activity with SB 203580 abolished the enhancement of MMP-13, as well as collagenase-1 (MMP-1) and 92-kDa gelatinase (MMP-9) expression by TNF-(alpha) and TGF-(beta). Blocking the ERK1, 2 pathway by PD 98059 had no effect on the induction of MMP-13 expression by TNF-(alpha) or TGF-(beta), but potently suppressed MMP-1 and MMP-9 production. Inhibition of p38 activity by SB 203580 also suppressed collagenolytic activity produced by both cell lines and inhibited invasion of TNF-(alpha) or TGF-(beta) stimulated A-5 cells through type I collagen and reconstituted basement membrane (Matrigel). These results show that activation of p38 MAPK pathway plays a crucial role in the invasive phenotype of transformed squamous epithelial cells, suggesting p38 MAPK as a target to specifically inhibit their invasion.


2007 ◽  
Vol 403 (3) ◽  
pp. 451-461 ◽  
Author(s):  
Sandrine Pacquelet ◽  
Jennifer L. Johnson ◽  
Beverly A. Ellis ◽  
Agnieszka A. Brzezinska ◽  
William S. Lane ◽  
...  

Exposure of neutrophils to LPS (lipopolysaccharide) triggers their oxidative response. However, the relationship between the signalling downstream of TLR4 (Toll-like receptor 4) after LPS stimulation and the activation of the oxidase remains elusive. Phosphorylation of the cytosolic factor p47phox is essential for activation of the NADPH oxidase. In the present study, we examined the hypothesis that IRAK-4 (interleukin-1 receptor-associated kinase-4), the main regulatory kinase downstream of TLR4 activation, regulates the NADPH oxidase through phosphorylation of p47phox. We show that p47phox is a substrate for IRAK-4. Unlike PKC (protein kinase C), IRAK-4 phosphorylates p47phox not only at serine residues, but also at threonine residues. Target residues were identified by tandem MS, revealing a novel threonine-rich regulatory domain. We also show that p47phox is phosphorylated in granulocytes in response to LPS stimulation. LPS-dependent phosphorylation of p47phox was enhanced by the inhibition of p38 MAPK (mitogen-activated protein kinase), confirming that the kinase operates upstream of p38 MAPK. IRAK-4-phosphorylated p47phox activated the NADPH oxidase in a cell-free system, and IRAK-4 overexpression increased NADPH oxidase activity in response to LPS. We have shown that endogenous IRAK-4 interacts with p47phox and they co-localize at the plasma membrane after LPS stimulation, using immunoprecipitation assays and immunofluorescence microscopy respectively. IRAK-4 was activated in neutrophils in response to LPS stimulation. We found that Thr133, Ser288 and Thr356, targets for IRAK-4 phosphorylation in vitro, are also phosphorylated in endogenous p47phox after LPS stimulation. We conclude that IRAK-4 phosphorylates p47phox and regulates NADPH oxidase activation after LPS stimulation.


2021 ◽  
Vol 99 (2) ◽  
pp. 218-223
Author(s):  
Mohamad Nusier ◽  
Mohammad Alqudah ◽  
Vijayan Elimban ◽  
Naranjan S. Dhalla

This study examined the effects of ischemic preconditioning (IP) on the ischemia/reperfusion (I/R) induced injury in normal and hypertrophied hearts. Cardiac hypertrophy in rabbits was induced by L-thyroxine (0.5 mg/kg/day for 16 days). Hearts with or without IP (3 cycles of 5 min ischemia and 10 min reperfusion) were subjected to I/R (60 min ischemia followed by 60 min reperfusion). IP reduced the I/R-induced infarct size from 68% to 24% and 57% to 33% in the normal and hypertrophied hearts, respectively. Leakage of creatine phosphokinase in the perfusate from the hypertrophied hearts due to I/R was markedly less than that form the normal hearts; IP prevented these changes. Although IP augmented the increase in phosphorylated p38-mitogen-activated protein kinase (p38-MAPK) content due to I/R, this effect was less in the hypertrophied than in the normal heart. These results suggest that reduced cardioprotection by IP of the I/R-induced injury in hypertrophied hearts may be due to reduced activation of p38-MAPK in comparison with normal hearts.


2011 ◽  
Vol 300 (1) ◽  
pp. E103-E110 ◽  
Author(s):  
Xiaoban Xin ◽  
Lijun Zhou ◽  
Caleb M. Reyes ◽  
Feng Liu ◽  
Lily Q. Dong

The adaptor protein APPL1 mediates the stimulatory effect of adiponectin on p38 mitogen-activated protein kinase (MAPK) signaling, yet the underlying mechanism remains unclear. Here we show that, in C2C12 cells, overexpression or suppression of APPL1 enhanced or suppressed, respectively, adiponectin-stimulated p38 MAPK upstream kinase cascade, consisting of transforming growth factor-β-activated kinase 1 (TAK1) and mitogen-activated protein kinase kinase 3 (MKK3). In vitro affinity binding and coimmunoprecipitation experiments revealed that TAK1 and MKK3 bind to different regions of APPL1, suggesting that APPL1 functions as a scaffolding protein to facilitate adiponectin-stimulated p38 MAPK activation. Interestingly, suppressing APPL1 had no effect on TNFα-stimulated p38 MAPK phosphorylation in C2C12 myotubes, indicating that the stimulatory effect of APPL1 on p38 MAPK activation is selective. Taken together, our study demonstrated that the TAK1-MKK3 cascade mediates adiponectin signaling and uncovers a scaffolding role of APPL1 in regulating the TAK1-MKK3-p38 MAPK pathway, specifically in response to adiponectin stimulation.


2002 ◽  
Vol 22 (20) ◽  
pp. 6931-6945 ◽  
Author(s):  
Ole Morten Seternes ◽  
Bjarne Johansen ◽  
Beate Hegge ◽  
Mona Johannessen ◽  
Stephen M. Keyse ◽  
...  

ABSTRACT The p38 mitogen-activated protein kinase (MAPK) pathway is an important mediator of cellular responses to environmental stress. Targets of p38 include transcription factors, components of the translational machinery, and downstream serine/threonine kinases, including MAPK-activated protein kinase 5 (MK5). Here we have used enhanced green fluorescent protein fusion proteins to analyze the subcellular localization of MK5. Although this protein is predominantly nuclear in unstimulated cells, MK5 shuttles between the nucleus and the cytoplasm. Furthermore, we have shown that the C-terminal domain of MK5 contains both a functional nuclear localization signal (NLS) and a leucine-rich nuclear export signal (NES), indicating that the subcellular distribution of this kinase reflects the relative activities of these two signals. In support of this, we have shown that stress-induced activation of the p38 MAPK stimulates the chromosomal region maintenance 1 protein-dependent nuclear export of MK5. This is regulated by both binding of p38 MAPK to MK5, which masks the functional NLS, and stress-induced phosphorylation of MK5 by p38 MAPK, which either activates or unmasks the NES. These properties may define the ability of MK5 to differentially phosphorylate both nuclear and cytoplasmic targets or alternatively reflect a mechanism whereby signals initiated by activation of MK5 in the nucleus may be transmitted to the cytoplasm.


Open Biology ◽  
2013 ◽  
Vol 3 (6) ◽  
pp. 130067 ◽  
Author(s):  
Gopal P. Sapkota

The signalling pathways downstream of the transforming growth factor beta (TGFβ) family of cytokines play critical roles in all aspects of cellular homeostasis. The phosphorylation and activation of p38 mitogen-activated protein kinase (MAPK) has been implicated in TGFβ-induced epithelial-to-mesenchymal transition and apoptosis. The precise molecular mechanisms by which TGFβ cytokines induce the phosphorylation and activation of p38 MAPK are unclear. In this study, I demonstrate that TGFβ-activated kinase 1 (TAK1/MAP3K7) does not play a role in the TGFβ-induced phosphorylation and activation of p38 MAPK in MEFs and HaCaT keratinocytes. Instead, RNAi -mediated depletion of MAP3K4 and MAP3K10 results in the inhibition of the TGFβ-induced p38 MAPK phosphorylation. Furthermore, the depletion of MAP3K10 from cells homozygously knocked-in with a catalytically inactive mutant of MAP3K4 completely abolishes the TGFβ-induced phosphorylation of p38 MAPK, implying that among MAP3Ks, MAP3K4 and MAP3K10 are sufficient for mediating the TGFβ-induced activation of p38 MAPK.


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