Lawrance Ian C, Wu Feng, Leite André Z A, Willis Joseph, West Gail A, Fiocchi Claudio, Chakravarti Shukti
Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA.
Gastroenterology. 2003 Dec;125(6):1750-61. doi: 10.1053/j.gastro.2003.08.027.
BACKGROUND & AIMS: 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.
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.
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.
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.
为阐明炎症性肠病常见并发症——肠道纤维化背后的细胞外基质（ECM）变化，我们建立了一种与肠道纤维化相关的慢性结肠炎小鼠模型。
通过每周直肠内注射三硝基苯磺酸（TNBS）建立慢性炎症。在该模型的2种变体中，预防性或治疗性给予核因子κB（NF-κB）p65的反义寡核苷酸以阻断与慢性炎症相关的纤维化。通过组织学确定结肠炎症和纤维化。通过羟脯氨酸定量估计总胶原蛋白水平。通过半定量逆转录聚合酶链反应评估胶原蛋白（Col1a2、Col3a2）、ECM重塑基因（基质金属蛋白酶[MMP]-1、-3和基质金属蛋白酶组织抑制剂[TIMP]-1）以及炎症调节细胞因子（肿瘤坏死因子α[TNF-α]、干扰素γ[IFN-γ]、转化生长因子β1[TGF-β1]和胰岛素样生长因子1[IGF-1]）的结肠表达。通过形态学、表型以及对TNF-α和IFN-γ的功能反应对对照和TNBS处理的结肠间充质细胞进行表征。
TNBS处理的小鼠结肠含有急性和慢性炎性浸润、胶原蛋白增加、纤维生成组织结构以及TNF-α、TGF-β1、IGF-1、Col1a2、MMP-1和TIMP-1的表达增加。TNBS处理的小鼠的结肠间充质细胞在形态上也与对照小鼠不同，对IFN-γ处理的反应中TIMP-1表达增加。TNBS处理停止后纤维化持续2至4周。预防性给予NF-κB反义的小鼠中，67%无纤维化，而在建立慢性炎症后进行治疗的小鼠中，43%无纤维化。
对小鼠进行延长的TNBS处理可产生与慢性肠道炎症相关的纤维化，并伴有广泛的纤维生成性ECM变化，可通过特异性阻断NF-κB来抵消。
