scholarly journals Intestinal trefoil factor binds to intestinal epithelial cells and induces nitric oxide production: priming and enhancing effects of mucin

1999 ◽  
Vol 338 (3) ◽  
pp. 745-751 ◽  
Author(s):  
Xiao-Di TAN ◽  
Qian-Ping LIU ◽  
Wei HSUEH ◽  
Yi-Hua CHEN ◽  
Hong CHANG ◽  
...  

Intestinal trefoil factor (ITF or TFF3), NO and epithelium-associated mucin have important roles in sustaining mucosal integrity in the gastrointestinal tract. In the present study we examined ITF-binding molecules on IEC-18 cells (an intestinal epithelial cell line) with the use of flow cytometry and localized these molecules on the cell surface by confocal microscopy. Furthermore, we studied the interaction of mucin and ITF and their co-operative effect on NO production by the epithelium. Stimulation of cells with mucin (5 mg/ml) for 90 min resulted in a 5-fold increase in ITF binding. Treatment of IEC-18 cells with actinomycin D or cycloheximide attenuated mucin-enhanced ITF binding. Ligand blot analysis confirmed the induction of ITF-binding protein in IEC-18 cells by mucin. These results indicate that transcriptional and translational mechanisms are involved in the effect of mucin. Treatment with ITF overnight resulted in a low level of nitrite production by the cells, a 5-fold increase over control, in a concentration-dependent manner. ITF-induced NO production was attenuated by 1400W, a selective type II nitric oxide synthase (NOS2) inhibitor. By immunoblotting we found that NOS2 was up-regulated by ITF treatment. Priming IEC-18 cells with mucin for 90 min enhanced the effect of ITF on NO production, suggesting that the up-regulation of ITF-binding molecules by mucin might be physiologically relevant. Taken together, these observations indicate (1) that ITF-binding molecules that are up-regulated by mucin exist on the intestinal epithelial surface, and (2) that ITF modulates epithelial NO production via the NOS2 pathway, which is enhanced by mucin.

2004 ◽  
Vol 72 (5) ◽  
pp. 2907-2914 ◽  
Author(s):  
Li Fang ◽  
Bogdan J. Nowicki ◽  
Petri Urvil ◽  
Pawel Goluszko ◽  
Stella Nowicki ◽  
...  

ABSTRACT We previously reported that inhibition of nitric oxide (NO) increases the rate of bacteremia and maternal mortality in pregnant rats with uterine infection by Escherichia coli expressing the Dr fimbria (Dr+). Epithelial binding and invasion by Dr+ E. coli has also been shown to be dependent upon the expression level of the cellular receptor decay-accelerating factor (DAF; CD55). Here, we hypothesize that NO-related severity of infection could be mediated by changes in DAF expression and in the rate of epithelial invasion. The cellular basis of NO effects on epithelial invasion with Dr+ E. coli was studied using Ishikawa endometrial carcinoma cells as an in vitro model of the human endometrial epithelium. Initially, we show that Ishikawa cells produce NO and express both NO synthase enzymes, NOS II and NOS III, and DAF protein. We next tested the abilities of both Dr+ E. coli and a Dr− E. coli mutant to invade Ishikawa cells, and invasion was seen only with Dr+ E. coli. Invasion by Dr+ E. coli was decreased by elevated NO production and increased by NO inhibition. Elevated NO production significantly decreased DAF protein and mRNA expression in Ishikawa cells in a time- and dose-dependent manner. Here, we propose that in vitro invasion of an epithelial cell line is directly related to NO-regulated expression of DAF. The significance of NO-regulated receptor-ligand invasion is that it may represent a novel unrecognized phenomenon of epithelial defense against infection.


1997 ◽  
Vol 272 (4) ◽  
pp. L707-L713 ◽  
Author(s):  
A. Burke-Gaffney ◽  
P. G. Hellewell

This study investigated whether endogenous nitric oxide (NO) limits cytokine-induced damage to the murine lung epithelial cell line LA-4. NO production was assessed as nitrite using the Griess reaction, and cell damage was assessed using ethidium homodimer-1. Cytotoxicity was first detected after a 24-h incubation with a combination of tumor necrosis factor-alpha, interleukin-1beta, and interferon-gamma (cytomix). Nitrite production increased to 78.0 +/- 0.5 nmol/10(6) cells at 24 h. Coincubation of LA-4 with cytomix and NO synthase inhibitors, aminoguanidine (3-1,000 microM) and N(G)-monomethyl-L-arginine (10-1,000 microM), but not N(G)-monomethyl-D-arginine, or a soluble guanylate cyclase inhibitor, 1H-[1,2,4] oxadiazole [4,3-a] quinoxalin-1-one, reduced cytomix-induced nitrite production and increased cytotoxicity up to twofold (24 h). Removal of L-arginine from the medium increased damage; reintroduction of 1,000 microM L-arginine, but not D-arginine, reversed this. In aminoguanidine-treated cells, replacement of NO with an NO donor, S-nitrosoglutathione (30 microM), reversed, in part, the cell damage observed in aminoguanidine/cytomix-treated cells. These results suggest that endogenous NO limits cytokine-induced lung epithelial damage.


1999 ◽  
Vol 276 (3) ◽  
pp. F433-F441 ◽  
Author(s):  
Tetsuo Umino ◽  
Eiji Kusano ◽  
Shigeaki Muto ◽  
Tetsu Akimoto ◽  
Satoru Yanagiba ◽  
...  

The present study examined how arginine vasopressin (AVP) affects nitric oxide (NO) metabolism in cultured rat glomerular mesangial cells (GMC). GMC were incubated with test agents and nitrite, and intracellular cGMP content, inducible nitric oxide synthase (iNOS) mRNA, and iNOS protein were analyzed by the Griess method, enzyme immunoassay, and Northern and Western blotting, respectively. AVP inhibited lipopolysaccharide (LPS)- and interleukin-1β (IL-1β)-induced nitrite production in a dose- and time-dependent manner, with concomitant changes in cGMP content, iNOS mRNA, and iNOS protein. This inhibition by AVP was reversed by V1- but not by oxytocin-receptor antagonist. Inhibition by AVP was also reproduced on LPS and interferon-γ (IFN-γ). Protein kinase C (PKC) inhibitors reversed AVP inhibition, whereas PKC activator inhibited nitrite production. Although dexamethasone and pyrrolidinedithiocarbamate (PDTC), inhibitors of nuclear factor-κB, inhibited nitrite production, further inhibition by AVP was not observed. AVP did not show further inhibition of nitrite production with actinomycin D, an inhibitor of transcription, or cycloheximide, an inhibitor of protein synthesis. In conclusion, AVP inhibits LPS- and IL-1β-induced NO production through a V1 receptor. The inhibitory action of AVP involves both the activation of PKC and the transcription of iNOS mRNA in cultured rat GMC.


1999 ◽  
Vol 277 (4) ◽  
pp. H1579-H1592 ◽  
Author(s):  
Samuel I. Hammerman ◽  
Elizabeth S. Klings ◽  
Katherine P. Hendra ◽  
Gilbert R. Upchurch ◽  
David C. Rishikof ◽  
...  

Acute chest syndrome (ACS) is the most common form of acute pulmonary disease associated with sickle cell disease. To investigate the possibility that alterations in endothelial cell (EC) production and metabolism of nitric oxide (NO) products might be contributory, we measured NO products from cultured pulmonary EC exposed to red blood cells and/or plasma from sickle cell patients during crisis. Exposure to plasma from patients with ACS caused a 5- to 10-fold increase in S-nitrosothiol (RSNO) and a 7- to 14-fold increase in total nitrogen oxide (NOx) production by both pulmonary arterial and microvascular EC. Increases occurred within 2 h of exposure to plasma in a concentration-dependent manner and were associated with increases in endothelial nitric oxide synthase (eNOS) protein and eNOS enzymatic activity, but not with changes in nitric oxide synthase (NOS) III or NOS II transcripts, inducible NOS (iNOS) protein nor iNOS enzymatic activity. RSNO and NOxincreased whether plasma was obtained from patients with ACS or other forms of vasoocclusive crisis. Furthermore, an oxidative state occurred and oxidative metabolites of NO, particularly peroxynitrite, were produced. These findings suggest that altered NO production and metabolism to damaging oxidative molecules contribute to the pathogenesis of ACS.


1998 ◽  
Vol 274 (1) ◽  
pp. C245-C252 ◽  
Author(s):  
Junsuke Igarashi ◽  
Masashi Nishida ◽  
Shiro Hoshida ◽  
Nobushige Yamashita ◽  
Hiroaki Kosaka ◽  
...  

The effects of nitric oxide (NO) produced by cardiac inducible NO synthase (iNOS) on myocardial injury after oxidative stress were examined. Interleukin-1β induced cultured rat neonatal cardiac myocytes to express iNOS. After induction of iNOS,l-arginine enhanced NO production in a concentration-dependent manner. Glutathione peroxidase (GPX) activity in myocytes was attenuated by elevated iNOS activity and by an NO donor, S-nitroso- N-acetyl-penicillamine (SNAP). Although NO production by iNOS did not induce myocardial injury, NO augmented release of lactate dehydrogenase from myocyte cultures after addition of H2O2(0.1 mM, 1 h). Inhibition of iNOS with Nω-nitro-l-arginine methyl ester ameliorated the effects of NO-enhancing treatments on myocardial injury and GPX activity. SNAP augmented the myocardial injury induced by H2O2. Inhibition of GPX activity with antisense oligodeoxyribonucleotide for GPX mRNA increased myocardial injury by H2O2. Results suggest that the induction of cardiac iNOS promotes myocardial injury due to oxidative stress via inactivation of the intrinsic antioxidant enzyme, GPX.


2007 ◽  
Vol 292 (4) ◽  
pp. G1070-G1078 ◽  
Author(s):  
Ryan M. Carlson ◽  
Stephan R. Vavricka ◽  
Jyrki J. Eloranta ◽  
Mark W. Musch ◽  
Donna L. Arvans ◽  
...  

Sustained expression of cytoprotective intestinal epithelial heat shock proteins (Hsps), particularly Hsp27, depends on stimuli derived from bacterial flora. In this study, we examined the role of the bacterial chemotactic peptide fMLP in stimulating colonic epithelial Hsp expression at concentrations encountered in a physiological milieu. Treatment of the polarized human intestinal epithelial cell line Caco2bbe with physiological concentrations of fMLP (10–100 nM) induced expression of Hsp27, but not Hsp72, in a time- and concentration-dependent manner. Induction of Hsp27 by fMLP was specific since the fMLP analogs MRP and MLP were not effective. Hsp27 induction by fMLP was blocked by the fMLP-receptor antagonist BOC-FLFLF and was blocked when the dipeptide transporter PepT1, an entry pathway for fMLP, was silenced. fMLP activated both the p38 and ERK1/2 MAP kinase pathways in Caco2bbe cells, but not the SAPK/JNK pathway. The p38 inhibitor SB203580, but not the MEK-1 inhibitor PD98059, blocked Hsp27 induction by fMLP. fMLP treatment inhibited actin depolymerization and decreased transepithelial resistance caused by the oxidant monochloramine, and this inhibition was reversed by silencing Hsp27 expression. fMLP pretreatment also inhibited activation of proinflammatory transcription factor NF-κB by TNF-α in Caco2bbe cells, reducing induction of NF-κB target genes by TNF-α both in human intestinal biopsies and Caco2bbe cells. In conclusion, fMLP may contribute to the maintenance of intestinal homeostasis by mediating physiological expression of Hsp27, enhancing cellular protection, and negatively regulating the inflammatory response.


1995 ◽  
Vol 269 (2) ◽  
pp. C519-C523 ◽  
Author(s):  
J. M. Li ◽  
R. A. Fenton ◽  
B. S. Cutler ◽  
J. G. Dobson

Adenosine per se is a potent vasodilator of vascular smooth muscle. Endothelial cells modulate vascular tone via the release of nitric oxide (NO), which also elicits vasodilation. This study was undertaken to determine whether adenosine could directly stimulate endothelial cells to enhance NO production, which could subsequently reduce vascular tone. NO production was evaluated in porcine carotid artery endothelial cells (PCAEC) and human saphenous vein endothelial cells (HSVEC) seeded on multiwell plates, grown to confluence, and treated with adenosine for 1 h. The bathing medium was collected, and the NO production was determined as reflected by the formation of NO2- and NO3-. NO production by PCAEC was significantly increased by adenosine in a dose-dependent manner, whereas there was only an insignificant tendency for an increase by HSVEC. The addition of the NO synthase competitive inhibitor, NG-monomethyl-L-arginine (NMMA), or the adenosine receptor antagonist, theophylline, prevented the increase in NO production by adenosine. The results suggest that adenosine stimulates, by a receptor-mediated mechanism, the production of NO by arterial, but not by venous, endothelial cells.


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