A murine model of chronic inflammation-induced intestinal fibrosis down-regulated by antisense NF-kappa B.
OBJECTIVE
To elucidate extracellular matrix (ECM) changes underlying intestinal fibrosis, a frequent complication of inflammatory bowel disease, we developed a murine model of chronic colitis associated with intestinal fibrosis.


METHODS
Chronic inflammation was established by weekly intrarectal administration of trinitrobenzene sulfonic acid (TNBS). In 2 variations of the model an antisense oligonucleotide for nuclear factor kappa B (NF-kappa B) p65 was given prophylactically or therapeutically to block chronic inflammation-associated fibrosis. Colonic inflammation and fibrosis were determined by histology. Total collagen level was estimated by hydroxyproline quantification. Colonic expression of collagens (Col1a2, Col3a2), ECM remodeling genes (matrix metalloproteinase [MMP]-1, -3, and tissue inhibitor of matrix metalloproteinase [TIMP]-1), and inflammation-modulating cytokines (tumor necrosis factor alpha [TNF-alpha], interferon gamma [IFN-gamma], transforming growth factor beta 1 [TGF-beta 1], and insulin-like growth factor 1 [IGF-1]) were assessed by semiquantitative reverse-transcription polymerase chain reaction. Control and TNBS-treated colonic mesenchymal cells were characterized by morphology, phenotype, and functional response to TNF-alpha and IFN-gamma.


RESULTS
Colons of TNBS-treated mice contained acute and chronic inflammatory infiltrates, increased collagen, fibrogenic tissue architecture, and increased expression of TNF-alpha, TGF-beta 1, IGF-1, Col1a2, MMP-1, and TIMP-1. Colonic mesenchymal cells from TNBS-treated mice were also morphologically distinct from those of the control mice, with increased TIMP-1 expression in response to IFN-gamma treatment. Fibrosis persisted for 2-4 weeks after cessation of the TNBS treatment. In mice given NF-kappa B antisense prophylactically, 67% were fibrosis-free, whereas of those treated after establishing chronic inflammation, 43% were free of fibrosis.


CONCLUSIONS
Extended TNBS treatment of mice yielded chronic intestinal inflammation-associated fibrosis with extensive fibrogenic ECM changes that could be counteracted by specific blockade of NF-kappa B.
Lawrance
Ian C
IC
Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA.
Wu
Feng
F
Leite
André Z A
AZ
Willis
Joseph
J
West
Gail A
GA
Fiocchi
Claudio
C
Chakravarti
Shukti
S
D000818:Animals; D002908:Chronic Disease; D003092:Colitis / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D003094:Collagen / Q000032:analysis; D003106:Colon / Q000473:pathology*; D004195:Disease Models, Animal; D005260:Female; D005355:Fibrosis; D007371:Interferon-gamma / Q000235:genetics / Q000494:pharmacology; D020781:Matrix Metalloproteinase 1 / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D016328:NF-kappa B / Q000037:antagonists & inhibitors*; D016376:Oligonucleotides, Antisense / Q000627:therapeutic use*; D012333:RNA, Messenger / Q000032:analysis; D051996:Transcription Factor RelA; D016212:Transforming Growth Factor beta / Q000235:genetics; D014302:Trinitrobenzenesulfonic Acid; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000494:pharmacology
D016328:NF-kappa B; D016376:Oligonucleotides, Antisense; D012333:RNA, Messenger; D051996:Transcription Factor RelA; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D014302:Trinitrobenzenesulfonic Acid; D003094:Collagen; D020781:Matrix Metalloproteinase 1