Bacterial lipopolysaccharide promotes profibrotic activation of intestinal fibroblasts.

Hdl Handle:
http://hdl.handle.net/10147/207477
Title:
Bacterial lipopolysaccharide promotes profibrotic activation of intestinal fibroblasts.
Authors:
Burke, J P; Cunningham, M F; Watson, R W G; Docherty, N G; Coffey, J C; O'Connell, P R
Affiliation:
Department of Surgery, St Vincent's University Hospital, Dublin, Ireland.
Citation:
Br J Surg. 2010 Jul;97(7):1126-34.
Journal:
The British journal of surgery
Issue Date:
1-Feb-2012
URI:
http://hdl.handle.net/10147/207477
DOI:
10.1002/bjs.7045
PubMed ID:
20632282
Abstract:
BACKGROUND: Fibroblasts play a critical role in intestinal wound healing. Lipopolysaccharide (LPS) is a cell wall component of commensal gut bacteria. The effects of LPS on intestinal fibroblast activation were characterized. METHODS: Expression of the LPS receptor, toll-like receptor (TLR) 4, was assessed in cultured primary human intestinal fibroblasts using flow cytometry and confocal microscopy. Fibroblasts were treated with LPS and/or transforming growth factor (TGF) beta1. Nuclear factor kappaB (NFkappaB) pathway activation was assessed by inhibitory kappaBalpha (IkappaBalpha) degradation and NFkappaB promoter activity. Fibroblast contractility was measured using a fibroblast-populated collagen lattice. Smad-7, a negative regulator of TGF-beta1 signalling, and connective tissue growth factor (CTGF) expression were assessed using reverse transcriptase-polymerase chain reaction and western blot. The NFkappaB pathway was inhibited by IkappaBalpha transfection. RESULTS: TLR-4 was present on the surface of intestinal fibroblasts. LPS treatment of fibroblasts induced IkappaBalpha degradation, enhanced NFkappaB promoter activity and increased collagen contraction. Pretreatment with LPS (before TGF-beta1) significantly increased CTGF production relative to treatment with TGF-beta1 alone. LPS reduced whereas TGF-beta1 increased smad-7 expression. Transfection with an IkappaBalpha plasmid enhanced basal smad-7 expression. CONCLUSION: Intestinal fibroblasts express TLR-4 and respond to LPS by activating NFkappaB and inducing collagen contraction. LPS acts in concert with TGF-beta1 to induce CTGF. LPS reduces the expression of the TGF-beta1 inhibitor, smad-7.
Language:
eng
MeSH:
Aged; Aged, 80 and over; Cells, Cultured; Colonic Neoplasms/metabolism; Connective Tissue Growth Factor/biosynthesis; Fibroblasts/*drug effects/metabolism; Humans; I-kappa B Kinase/metabolism; Lipopolysaccharides/*pharmacology; Middle Aged; NF-kappa B/metabolism; Smad7 Protein/metabolism; Toll-Like Receptor 4/*metabolism; Transforming Growth Factor beta1/*pharmacology; Wound Healing/*physiology
ISSN:
1365-2168 (Electronic); 0007-1323 (Linking)

Full metadata record

DC FieldValue Language
dc.contributor.authorBurke, J Pen_GB
dc.contributor.authorCunningham, M Fen_GB
dc.contributor.authorWatson, R W Gen_GB
dc.contributor.authorDocherty, N Gen_GB
dc.contributor.authorCoffey, J Cen_GB
dc.contributor.authorO'Connell, P Ren_GB
dc.date.accessioned2012-02-01T10:28:56Z-
dc.date.available2012-02-01T10:28:56Z-
dc.date.issued2012-02-01T10:28:56Z-
dc.identifier.citationBr J Surg. 2010 Jul;97(7):1126-34.en_GB
dc.identifier.issn1365-2168 (Electronic)en_GB
dc.identifier.issn0007-1323 (Linking)en_GB
dc.identifier.pmid20632282en_GB
dc.identifier.doi10.1002/bjs.7045en_GB
dc.identifier.urihttp://hdl.handle.net/10147/207477-
dc.description.abstractBACKGROUND: Fibroblasts play a critical role in intestinal wound healing. Lipopolysaccharide (LPS) is a cell wall component of commensal gut bacteria. The effects of LPS on intestinal fibroblast activation were characterized. METHODS: Expression of the LPS receptor, toll-like receptor (TLR) 4, was assessed in cultured primary human intestinal fibroblasts using flow cytometry and confocal microscopy. Fibroblasts were treated with LPS and/or transforming growth factor (TGF) beta1. Nuclear factor kappaB (NFkappaB) pathway activation was assessed by inhibitory kappaBalpha (IkappaBalpha) degradation and NFkappaB promoter activity. Fibroblast contractility was measured using a fibroblast-populated collagen lattice. Smad-7, a negative regulator of TGF-beta1 signalling, and connective tissue growth factor (CTGF) expression were assessed using reverse transcriptase-polymerase chain reaction and western blot. The NFkappaB pathway was inhibited by IkappaBalpha transfection. RESULTS: TLR-4 was present on the surface of intestinal fibroblasts. LPS treatment of fibroblasts induced IkappaBalpha degradation, enhanced NFkappaB promoter activity and increased collagen contraction. Pretreatment with LPS (before TGF-beta1) significantly increased CTGF production relative to treatment with TGF-beta1 alone. LPS reduced whereas TGF-beta1 increased smad-7 expression. Transfection with an IkappaBalpha plasmid enhanced basal smad-7 expression. CONCLUSION: Intestinal fibroblasts express TLR-4 and respond to LPS by activating NFkappaB and inducing collagen contraction. LPS acts in concert with TGF-beta1 to induce CTGF. LPS reduces the expression of the TGF-beta1 inhibitor, smad-7.en_GB
dc.language.isoengen_GB
dc.subject.meshAgeden_GB
dc.subject.meshAged, 80 and overen_GB
dc.subject.meshCells, Cultureden_GB
dc.subject.meshColonic Neoplasms/metabolismen_GB
dc.subject.meshConnective Tissue Growth Factor/biosynthesisen_GB
dc.subject.meshFibroblasts/*drug effects/metabolismen_GB
dc.subject.meshHumansen_GB
dc.subject.meshI-kappa B Kinase/metabolismen_GB
dc.subject.meshLipopolysaccharides/*pharmacologyen_GB
dc.subject.meshMiddle Ageden_GB
dc.subject.meshNF-kappa B/metabolismen_GB
dc.subject.meshSmad7 Protein/metabolismen_GB
dc.subject.meshToll-Like Receptor 4/*metabolismen_GB
dc.subject.meshTransforming Growth Factor beta1/*pharmacologyen_GB
dc.subject.meshWound Healing/*physiologyen_GB
dc.titleBacterial lipopolysaccharide promotes profibrotic activation of intestinal fibroblasts.en_GB
dc.contributor.departmentDepartment of Surgery, St Vincent's University Hospital, Dublin, Ireland.en_GB
dc.identifier.journalThe British journal of surgeryen_GB
dc.description.provinceLeinster-
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