scholarly journals Nintedanib Regulates GRK2 and CXCR2 to Reduce Neutrophil Recruitment in Endotoxin-Induced Lung Injury

2021 ◽  
Vol 22 (18) ◽  
pp. 9898
Author(s):  
Vincent Yi-Fong Su ◽  
Wei-Chih Chen ◽  
Wen-Kuang Yu ◽  
Huai-Hsuan Wu ◽  
Hao Chen ◽  
...  

The role of nintedanib, a multiple tyrosine kinase inhibitor, in the treatment of sepsis-induced acute lung injury (ALI) remains unclear. Lipopolysaccharide (LPS), also known as endotoxin, has been used to induce ALI. The goal of this study was to assess the effect of nintedanib in attenuating the histopathological changes of LPS-induced ALI. Nintedanib was administered via oral gavage to male C57BL/6 mice 24 h and 10 min before intratracheal endotoxin instillation. Lung histopathological characteristics, adhesion molecule expression, and the regulatory signaling pathways of neutrophil chemotaxis were analyzed after 24 h. We found that nintedanib significantly reduced histopathological changes and neutrophil recruitment in LPS-induced ALI. The number of neutrophils in bronchoalveolar lavage fluid (BALF) was reduced in nintedanib-treated relative to untreated mice with ALI. Nintedanib mediated the downregulation of the chemotactic response to LPS by reducing the expression of adhesion molecules and the phosphorylated p38:total p38 mitogen-activated protein kinase (MAPK) ratio in the lungs of mice with ALI. Nintedanib also reduced the expression of lymphocyte antigen 6 complex locus G6D (Ly6G) and very late antigen 4 (VLA-4) in BALF neutrophils and mediated the downregulation of chemokine (C-X-C motif) receptor 2 (CXCR2) and upregulation of G protein-coupled receptor kinase 2 (GRK2) activity in peripheral blood neutrophils in mice with LPS-induced ALI. Nintedanib improved the histopathological changes of LPS-induced ALI by reducing neutrophil chemotaxis. These effects were mediated by the inhibition of adhesion molecules via the activation of GRK2 and the inhibition of p38 MAPK and CXCR2.

2002 ◽  
Vol 282 (6) ◽  
pp. L1324-L1329 ◽  
Author(s):  
Andre Kulisz ◽  
Ningfang Chen ◽  
Navdeep S. Chandel ◽  
Zuohui Shao ◽  
Paul T. Schumacker

The p38 mitogen-activated protein kinase (MAPK) is phosphorylated in response to oxidative stress. Mitochondria in cardiomyocytes increase their generation of reactive oxygen species (ROS) during hypoxia (1–5% O2). These ROS participate in signal transduction pathways involved in adaptive responses, including ischemic preconditioning and gene transcription. The present study therefore tested the hypothesis that hypoxia induces p38 MAPK phosphorylation by augmenting mitochondrial ROS generation. In cardiomyocytes, phosphorylation of p38 was observed in a Po 2-dependent manner during hypoxia. This response was inhibited by rotenone, thenoyltrifluoroacetone, and myxothiazol, inhibitors of mitochondrial complexes I, II, and III, respectively. A similar inhibition was observed in the cells pretreated with anion channel inhibitor DIDS, which may block ROS release from mitochondria. During normoxia, increases in mitochondrial ROS elicited by azide (1–2 mM) or by the mitochondrial inhibitor antimycin A caused increased phosphorylation of p38. Brief treatment with exogenous H2O2 during normoxia also induced phosphorylation of p38 as hypoxia, but this effect was not abolished by myxothiazol or DIDS. The antioxidant N-acetyl-cysteine abolished the p38 response to hypoxia, presumably by scavenging H2O2, but the mitogen extracellular receptor kinase inhibitor PD-98059 did not inhibit p38 phosphorylation during hypoxia. Thus physiological hypoxia leads to p38 phosphorylation through a mechanism that requires electron flux in the proximal region of the mitochondrial electron transport chain, which suggests that either H2O2 or superoxide participates in activating that process.


2004 ◽  
pp. 233-240 ◽  
Author(s):  
AM Nanzer ◽  
S Khalaf ◽  
AM Mozid ◽  
RC Fowkes ◽  
MV Patel ◽  
...  

OBJECTIVES: Ghrelin is a brain-gut peptide with GH-releasing and appetite-inducing activities and a widespread tissue distribution. Ghrelin is the endogenous ligand of the GH secretagogue receptor type 1a (GHS-R1a), and both ghrelin and the GHS-R1a are expressed in the pituitary. There are conflicting data regarding the effects of ghrelin on cell proliferation. A positive effect on proliferation and activation of the mitogen-activated protein kinase (MAPK) pathway has been found in hepatoma, adipose, cardiomyocyte and prostate cell lines. However, ghrelin has also been shown to have anti-proliferative effects on breast, lung and thyroid cell lines. We therefore examined the effect of ghrelin on the rat pituitary cell line GH3. METHODS: RT-PCR was used for the detection of GHS-R1a and pre-proghrelin mRNA expression in GH3 cells. The effect of ghrelin on cell proliferation was studied using [(3)H]thymidine incorporation; cell counting and the activation of the MAPK pathway were studied using immunoblotting and inhibitors of the extracellular signal-regulated kinase 1 and 2 (ERK 1/2), protein kinase C (PKC) and tyrosine phosphatase pathways. RESULTS: GHS-R1a and ghrelin mRNA expression were detected in GH3 cells. Ghrelin, at 10(-10) to 10(-6) M concentrations, significantly increased [(3)H]thymidine incorporation (at 10(-9) M, 183+/-13% (means+/-s.e.m.) compared with untreated controls), while 12-phorbol 13-myristate acetate (PMA) at 10(-7) M (used as a positive control) caused a 212+/-14% increase. A reproducible stimulatory effect of desoctanoyl ghrelin was also observed on [(3)H]thymidine incorporation (135+/-5%; P<0.01 at 10(-9) M compared with control), as well as on the cell count (control 6.8 x 10(4)+/-8.7 x 10(3) cells/ml vs desoctanoyl ghrelin (10(-9) M) 1.04 x 10(5)+/-7.5 x 10(3) cells/ml; P<0.01). Ghrelin caused a significant increase in phosphorylated ERK 1/2 in immunoblotting, while desoctanoyl ghrelin showed a smaller but also significant stimulatory effect. The positive effect of ghrelin and desoctanoyl ghrelin on [(3)H]thymidine incorporation was abolished by the MAPK kinase inhibitor U0126, the PKC inhibitor GF109203X and the tyrosine kinase inhibitor tyrphostin 23, suggesting that the ghrelin-induced cell proliferation of GH3 cells is mediated both via a PKC-MAPK-dependent pathway and via a tyrosine kinase-dependent pathway. This could also be clearly demonstrated by Western blot analysis, where a transient increase in ERK 1/2 phosphorylation by ghrelin was attenuated by all three inhibitors. CONCLUSION: We have shown a novel role for ghrelin in stimulating the proliferation of a somatotroph pituitary tumour cell line, suggesting that ERK activation is involved in mediating the effects of ghrelin on cell proliferation. Desoctanoyl ghrelin showed a similar effect. As ghrelin has been shown to be expressed in both normal and adenomatous pituitary tissue, locally produced ghrelin may play a role in pituitary tumorigenesis via an autocrine/paracrine pathway.


2021 ◽  
Vol 22 (11) ◽  
pp. 5533
Author(s):  
Alessio Filippo Peritore ◽  
Ramona D’Amico ◽  
Rosalba Siracusa ◽  
Marika Cordaro ◽  
Roberta Fusco ◽  
...  

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are common and devastating clinical disorders with high mortality and no specific therapy. Lipopolysaccharide (LPS) is usually used intratracheally to induce ALI in mice. The aim of this study was to examine the effects of an ultramicronized preparation of palmitoylethanolamide (um-PEA) in mice subjected to LPS-induced ALI. Histopathological analysis reveals that um-PEA reduced alteration in lung after LPS intratracheal administration. Besides, um-PEA decreased wet/dry weight ratio and myeloperoxidase, a marker of neutrophils infiltration, macrophages and total immune cells number and mast cells degranulation in lung. Moreover, um-PEA could also decrease cytokines release of interleukin (IL)-6, interleukin (IL)-1β, tumor necrosis factor (TNF)-α and interleukin (IL)-18. Furthermore, um-PEA significantly inhibited the phosphorylation of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation in ALI, and at the same time decreased extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38/MAPK) expression, that was increased after LPS administration. Our study suggested that um-PEA contrasted LPS-induced ALI, exerting its potential role as an adjuvant anti-inflammatory therapeutic for treating lung injury, maybe also by p38/NF-κB pathway.


2001 ◽  
Vol 281 (6) ◽  
pp. G1405-G1412 ◽  
Author(s):  
T. Suzuki ◽  
E. Grand ◽  
C. Bowman ◽  
J. L. Merchant ◽  
A. Todisco ◽  
...  

Helicobacter pyloriand proinflammatory cytokines have a direct stimulatory effect on gastrin release from isolated G cells, but little is known about the mechanism by which these factors regulate gastrin gene expression. We explored whether tumor necrosis factor (TNF)-α and interleukin (IL)-1 directly regulate gastrin gene expression and, if so, by what mechanism. TNF-α and IL-1 significantly increased gastrin mRNA in canine G cells to 181 ± 18% and 187 ± 28% of control, respectively, after 24 h of treatment. TNF-α and IL-1 stimulated gastrin promoter activity to a maximal level of 285 ± 12% and 415 ± 26% of control. PD-98059 (a mitogen-activated protein kinase kinase inhibitor), SB-202190 (a p38 kinase inhibitor), and GF-109203 (a protein kinase C inhibitor) inhibited the stimulatory action of both cytokines on the gastrin promoter. In conclusion, both cytokines can directly regulate gastrin gene expression via a mitogen-activated protein kinase- and protein kinase C-dependent mechanism. These data suggest that TNF-α and IL-1 may play a direct role in Helicobacter pylori-induced hypergastrinemia.


2008 ◽  
Vol 7 (8) ◽  
pp. 1309-1317 ◽  
Author(s):  
Iwona Migdal ◽  
Yulia Ilina ◽  
Markus J. Tamás ◽  
Robert Wysocki

ABSTRACT Cells slow down cell cycle progression in order to adapt to unfavorable stress conditions. Yeast (Saccharomyces cerevisiae) responds to osmotic stress by triggering G1 and G2 checkpoint delays that are dependent on the mitogen-activated protein kinase (MAPK) Hog1. The high-osmolarity glycerol (HOG) pathway is also activated by arsenite, and the hog1Δ mutant is highly sensitive to arsenite, partly due to increased arsenite influx into hog1Δ cells. Yeast cell cycle regulation in response to arsenite and the role of Hog1 in this process have not yet been analyzed. Here, we found that long-term exposure to arsenite led to transient G1 and G2 delays in wild-type cells, whereas cells that lack the HOG1 gene or are defective in Hog1 kinase activity displayed persistent G1 cell cycle arrest. Elevated levels of intracellular arsenite and “cross talk” between the HOG and pheromone response pathways, observed in arsenite-treated hog1Δ cells, prolonged the G1 delay but did not cause a persistent G1 arrest. In contrast, deletion of the SIC1 gene encoding a cyclin-dependent kinase inhibitor fully suppressed the observed block of G1 exit in hog1Δ cells. Moreover, the Sic1 protein was stabilized in arsenite-treated hog1Δ cells. Interestingly, Sic1-dependent persistent G1 arrest was also observed in hog1Δ cells during hyperosmotic stress. Taken together, our data point to an important role of the Hog1 kinase in adaptation to stress-induced G1 cell cycle arrest.


2001 ◽  
Vol 280 (2) ◽  
pp. L354-L362 ◽  
Author(s):  
Pamela M. Lindroos ◽  
Yi-Zhe Wang ◽  
Annette B. Rice ◽  
James C. Bonner

Upregulation of the platelet-derived growth factor (PDGF) receptor-α (PDGFR-α) is a mechanism of myofibroblast hyperplasia during pulmonary fibrosis. We previously identified interleukin (IL)-1β as a major inducer of the PDGFR-α in rat pulmonary myofibroblasts in vitro. In this study, we report that staurosporine, a broad-spectrum kinase inhibitor, upregulates PDGFR-α gene expression and protein. A variety of other kinase inhibitors did not induce PDGFR-α expression. Staurosporine did not act via an IL-1β autocrine loop because the IL-1 receptor antagonist protein did not block staurosporine-induced PDGFR-α expression. Furthermore, staurosporine did not activate a variety of signaling molecules that were activated by IL-1β, including nuclear factor-κB, extracellular signal-regulated kinase, and c-Jun NH2-terminal kinase. However, both staurosporine- and IL-1β-induced phosphorylation of p38 mitogen-activated protein kinase and upregulation of PDGFR-α by these two agents was inhibited by the p38 inhibitor SB-203580. Finally, staurosporine inhibited basal and PDGF-stimulated mitogenesis over the same concentration range that induced PDGFR-α expression. Collectively, these data demonstrate that staurosporine is a useful tool for elucidating the signaling mechanisms that regulate PDGFR expression in lung connective tissue cells and possibly for evaluating the role of the PDGFR-α as a growth arrest-specific gene.


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