Stimulation of protein kinase C activity by tumor necrosis factor-α in bovine bronchial epithelial cells

1997 ◽  
Vol 273 (5) ◽  
pp. L1007-L1012 ◽  
Author(s):  
Todd A. Wyatt ◽  
Harumasa Ito ◽  
Thomas J. Veys ◽  
John R. Spurzem
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Tumor Necrosis Factor ◽  
Epithelial Cells ◽  
Tumor Necrosis ◽  
Bronchial Epithelial ◽  
Calphostin C ◽  
Kinase C ◽  
Tnf Α ◽  
Necrosis Factor

Bronchial epithelial cell migration, attachment, and proliferation are important processes in response to airway injury. We have shown that tumor necrosis factor (TNF)-α stimulates the migration of bovine bronchial epithelial cells (BBEC) in vitro. We hypothesized that protein kinase C (PKC) may be one of the intracellular signaling mediators of TNF-α in BBEC. In this study, we have identified multiple PKC isoforms in BBEC and measured total cellular PKC activity. Polyclonal antibodies to the PKC-α, -β2, -δ, and -ε isoforms recognized protein bands around 80–90 kDa. BBEC primary cultures treated with either 500 U/ml TNF-α for 2–4 h or 100 ng/ml 12- O-tetradecanoylphorbol 13-acetate for 15 min resulted in three- to fivefold increases in PKC activity in the particulate fractions of crude cell lysates. This activity was inhibited by 1 μM calphostin C or 10 μM H-7. Similarly, TNF-α-stimulated BBEC migration was reduced at least twofold in the presence of H-7 or calphostin C. These studies suggest that the activation of PKC is necessary for TNF-α-stimulated BBEC migration.

Increase of Mucous Glycoprotein Secretion by Tumor Necrosis Factor Alpha via a Protein Kinase C-Dependent Mechanism in Cultured Chinchilla Middle Ear Epithelial Cells

1998 ◽  
Vol 107 (3) ◽  
pp. 213-219 ◽  
Author(s):  
Jizhen Lin ◽  
Youngki Kim ◽  
Steven K. Juhn
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Tumor Necrosis Factor ◽  
Epithelial Cells ◽  
Middle Ear ◽  
Tumor Necrosis ◽  
Kinase C ◽  
Tnf Α ◽  
Necrosis Factor ◽  
Dependent Mechanism

Tumor necrosis factor α (TNF-α), originally defined by its antitumoral activity, is now recognized as a polypeptide mediator of inflammatory and cellular immune response. Recent studies have demonstrated that TNF-α exists in the fluid of otitis media with effusion and, therefore, suggested its possible role in the pathogenesis of mucus hypersecretion. In this study, the effects of TNF-α on mucous glycoprotein (MGP) secretion from cultured chinchilla middle ear epithelial cells were examined, and TNF-α was found to stimulate MGP secretion in a time- and concentration-dependent manner. The action of TNF-α on MGP secretion was significantly and dose-dependently inhibited by TNF-α monoclonal antibody; this finding is suggestive of its specificity on MGP secretion. The addition of the protein kinase C inhibitor 1-(5-isoquinolinylsulfonyl)-2-methylpiperidine (H-7) to the culture significantly blocked TNF-α-induced MGP secretion, while the calmodulin inhibitor N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) did not. This suggests that TNF-α stimulates MGP secretion via a protein kinase C—dependent mechanism.

Ceramide mediates inhibition of the renal epithelial sodium channel by tumor necrosis factor-α through protein kinase C

2007 ◽  
Vol 293 (4) ◽  
pp. F1178-F1186 ◽  
Author(s):  
Hui-Fang Bao ◽  
Zhi-Ren Zhang ◽  
You-You Liang ◽  
Joshua J. Ma ◽  
Douglas C. Eaton ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Tumor Necrosis Factor ◽  
Sodium Channel ◽  
Tumor Necrosis ◽  
Tumor Necrosis Factor Α ◽  
Kinase C ◽  
Tnf Α ◽  
Factor Α ◽  
Necrosis Factor

To determine whether ceramide mediates regulation of the renal epithelial sodium channel (ENaC) by tumor necrosis factor-α (TNF-α), confocal microscopy and patch-clamp experiments were performed in A6 distal nephron cells. We found that TNF-α (100 ng/ml) had no effect on ENaC activity and ceramide level when the cells were grown in the presence of aldosterone, but significantly inhibited ENaC and induced ceramide production after the cells were pretreated with LY 294002, an inhibitor of phosphatidylinositol 3-kinase, for 24 h. The inhibition of ENaC induced by TNF-α was mimicked by exogenous sphingomyelinase (0.1 U/ml) and C2-ceramide (50 μM), but neither C2-dihydroceramide, a membrane-impermeable analog of C2-ceramide, nor choline, and abolished by pretreatment with GF109203X, a protein kinase C (PKC) inhibitor. C2-ceramide failed to affect ENaC in the cells pretreated with GF109203X, but not in the cells pretreated with PD-98059, a mitogen-activated protein kinase kinase inhibitor. C2-ceramide induced the externalization of phosphatidylserine (PS) in control A6 cells, but not in the cells pretreated with GF109203X. Together with our previous finding that cytosolic PS maintains ENaC activity in A6 cells, these data suggest that ceramide mediates TNF-α inhibition of the renal ENaC via a pathway associated with PKC-dependent externalization of PS.

Tumor necrosis factor-alpha decreases pulmonary artery endothelial nitrovasodilator via protein kinase C

1994 ◽  
Vol 267 (3) ◽  
pp. L318-L325 ◽  
Author(s):  
A. Johnson ◽  
D. T. Phelps ◽  
T. J. Ferro
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Tumor Necrosis Factor ◽  
Pulmonary Artery ◽  
Tumor Necrosis ◽  
Necrosis Factor Alpha ◽  
Calphostin C ◽  
Kinase C ◽  
Factor Alpha ◽  
Necrosis Factor

We postulated that tumor necrosis factor-alpha (TNF) decreases endothelium-derived nitrovasodilator(s) via a protein kinase C (PKC)-dependent pathway. Calf pulmonary artery endothelial monolayers (PAEM) were treated with TNF (10, 100, and 1,000 U/ml) for 15 min or 18 h during an 18-h incubation. At the end of the incubation, the cell lysate and supernatant were harvested. Compared with controls, an 18-h incubation with TNF (100 and 1,000 U/ml) resulted in a decrease in NO2- [the oxidation product of nitric oxide (NO)] in PAEM lysate and supernatant. TNF (100 U/ml) treatment for 15 min did not suppress NO2- levels. The decrease in NO2- and the increase in lipid peroxides in response to TNF were prevented by pretreatment (15 min prior to and throughout the incubation) with either calphostin C (1 microM; a specific PKC inhibitor) or the antioxidants N-acetylcysteine (1 mM), 4,5-dihydroxy-1,3-benzene disulfonic acid (Tiron) (10 mM), and superoxide dismutase (10 U/ml). Treatment with phorbol 12-myristate 13-acetate (PMA, 1 microM for 15 min), an activator of PKC, decreased NO2- similarly to TNF. Pretreatment with calphostin C or N-acetylcysteine prior to TNF (10 U/ml) revealed an increase in NO2- levels above control treatment. Treatment with the NO synthase antagonists NG-monomethyl-L-arginine (1 mM) and N-nitroso-L-arginine (1 mM) induced an L-arginine (1 mM)-dependent decrease in NO2- in control but not in TNF-treated PAEM. The induction of NO2- by calcium ionophore (A23187; 500 nM) was not affected by treatment with TNF.(ABSTRACT TRUNCATED AT 250 WORDS)

Activation of protein kinase C mediates altered pulmonary vasoreactivity induced by tumor necrosis factor-alpha

1994 ◽  
Vol 267 (3) ◽  
pp. L282-L290 ◽  
Author(s):  
G. Serfilippi ◽  
T. J. Ferro ◽  
A. Johnson
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Tumor Necrosis Factor ◽  
Tumor Necrosis ◽  
Necrosis Factor Alpha ◽  
Calphostin C ◽  
Kinase C ◽  
Factor Alpha ◽  
Pkc Activation ◽  
Necrosis Factor

We postulated that tumor necrosis factor-alpha (TNF) "primes" the lung for the development of pulmonary vasoconstriction and edema by activating protein kinase C (PKC). Guinea pigs were injected with TNF (1.6 x 10(5) U/kg i.p.), and the lungs were isolated 4 h later. Compared with controls, TNF pretreatment resulted in greater increases in pulmonary vascular resistance and pressure and lung weight, in response to the thromboxane A2 mimetic, U-46619 (122 pmol/min). Treatment with TNF resulted in 1) pulmonary arterial endothelial PKC activation, 2) increased lung polymorphonuclear neutrophil (PMN) sequestration, 3) increased levels of superoxide radical (O2.) in lung effluent, and 4) decreased nitrite levels (NO2-, oxidation product of nitric oxide) in lung effluent. Intraperitoneal treatment with calphostin C (3 microM, 15 min prior to treatment with TNF) prevented the effects of TNF on 1) PKC activation, 2) the hemodynamic responses to U-46619, and 3) the levels of NO2- and O2(.). PKC activation does not mediate TNF-induced lung sequestration of PMN, since calphostin C had no effect on lung myeloperoxidase activity. The data suggest that PKC activation mediates TNF-induced 1) increases in O2., 2) decreases in NO2-, and 3) increases in vasoreactivity and edema in response to U-46619.

Tumor necrosis factor-alpha activates pulmonary artery endothelial protein kinase C

1993 ◽  
Vol 264 (1) ◽  
pp. L7-L14 ◽  
Author(s):  
T. J. Ferro ◽  
D. M. Parker ◽  
L. M. Commins ◽  
P. G. Phillips ◽  
A. Johnson
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Tumor Necrosis Factor ◽  
Pulmonary Artery ◽  
Tumor Necrosis Factor Alpha ◽  
Tumor Necrosis ◽  
Necrosis Factor Alpha ◽  
Kinase C ◽  
Factor Alpha ◽  
Necrosis Factor

We investigated the hypothesis that tumor necrosis factor-alpha (TNF) activates pulmonary endothelial protein kinase C (PKC). Confluent bovine pulmonary artery endothelial monolayers were exposed to recombinant human TNF, and the translocation of PKC, an indicator of enzyme activation, was studied using both slot immunoblotting and immunofluorescence. For slot immunoblot analysis, membrane and cytosol lysate fractions were prepared, and PKC antigen was assessed using MC5 monoclonal anti-PKC antibody. TNF (1,000 U/ml for 15 min) induced translocation of PKC into the membrane. Immunofluorescence analysis with the MC5 antibody was also used. Monolayers treated with culture medium showed diffuse cytoplasmic fluorescence. In contrast, treatment with either TNF (1,000 U/ml for 15 min) or 1,2-dioctanoylglycerol (4 x 10(-5) M for 5 min), a diacylglycerol that activates PKC, resulted in translocation of fluorescence to the cell periphery; fine, punctate PKC-associated fluorescence was localized to the margins of cells. The TNF-induced translocation of PKC was inhibited using either IP-300 polyclonal anti-TNF antibody (indicating that the TNF effect was not due to the vehicle or contaminating endotoxin) or calphostin C (10(-6) M for 15 min), which inhibits PKC activation by interacting with the regulatory diacylglycerol-binding domain. TNF treatment had no effect on either the content of PKC, or of total protein, in the membrane + cytosol, and cycloheximide (40 microM for 5 min) did not alter the translocation of PKC induced by TNF; these results indicate that the effect of TNF on PKC translocation was related to neither de novo membrane synthesis of PKC (as opposed to translocation per se) nor nonspecific augmentation of protein synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Downregulation of tumor necrosis factor (TNF) sensitivity via modulation of TNF binding capacity by protein kinase C activators.

1987 ◽  
Vol 166 (6) ◽  
pp. 1788-1797 ◽  
Author(s):  
R Unglaub ◽  
B Maxeiner ◽  
B Thoma ◽  
K Pfizenmaier ◽  
P Scheurich
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Tumor Necrosis Factor ◽  
Tumor Necrosis ◽  
Binding Capacity ◽  
Receptor Protein ◽  
Tnf Alpha ◽  
Tnf Receptor ◽  
Kinase C ◽  
Necrosis Factor

The regulatory action of activators for protein kinase C on the specific binding capacity for recombinant human tumor necrosis factor alpha (TNF-alpha) was studied on various human cell lines. Phorbol myristate acetate (PMA) and oleyl acetyl glycerol (OAG) both are able to rapidly downregulate TNF-binding capacity of normal and malignant cells derived from various tissues. As PMA treatment did not enhance internalization of TNF-alpha-receptor complexes at 37 degrees C, and since OAG was able to downregulate TNF-binding capacity under conditions where internalization and shedding of receptor protein are prevented, we conclude that protein kinase C controls ligand affinity of the TNF-receptor protein, possibly via direct phosphorylation. Protein kinase C triggered downregulation of TNF-alpha-binding capacity concomitantly resulted in reduction of TNF-alpha sensitivity, as revealed from decreased cytotoxic action of TNF-alpha on L 929 cells and from inhibition of TNF-alpha-mediated enhancement of HLA class II antigen expression in Colo 205 cells. Restoration of TNF-binding capacity upon abrogation of protein kinase C stimulation leads to full recovery of TNF responsiveness, further supporting the close linkage of TNF-receptor expression and TNF sensitivity. These data suggest that regulation of TNF-binding capacity by protein kinase C is one of the cellular control mechanisms of TNF responsiveness.

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