柳氮磺胺吡啶对核因子-κB活性的抑制作用是通过直接抑制IκB激酶α和β介导的。

Suppression of NF-kappaB activity by sulfasalazine is mediated by direct inhibition of IkappaB kinases alpha and beta.

作者信息

Weber C K, Liptay S, Wirth T, Adler G, Schmid R M

机构信息

Department of Internal Medicine I, University of Ulm, Ulm, Germany.

出版信息

Gastroenterology. 2000 Nov;119(5):1209-18. doi: 10.1053/gast.2000.19458.

DOI:10.1053/gast.2000.19458

PMID:11054378

Abstract

BACKGROUND & AIMS: Activation of NF-kappaB/Rel has been implicated in the pathogenesis of inflammatory bowel disease (IBD). Various drugs used in the treatment of IBD, such as glucocorticoids, 5-aminosalicylic acid, and sulfasalazine, interfere with NF-kappaB/Rel signaling. The aim of this study was to define the molecular mechanism by which sulfasalazine inhibits NF-kappaB activation.

METHODS

The effects of sulfasalazine and its moieties on NF-kappaB signaling were evaluated using electromobility shift, transfection, and immune complex kinase assays. The direct effect of sulfasalazine on IkappaB kinase (IKK) activity was investigated using purified recombinant IKK-alpha and -beta proteins.

RESULTS

NF-kappaB/Rel activity induced by tumor necrosis factor alpha, 12-O-tetradecanoylphorbol-13-acetate, or overexpression of NF-kappaB-inducing kinase, IKK-alpha, IKK-beta, or constitutively active IKK-alpha and IKK-beta mutants was inhibited dose dependently by sulfasalazine. Sulfasalazine inhibited tumor necrosis factor alpha-induced activation of endogenous IKK in Jurkat T cells and SW620 colon cells, as well as the catalytic activity of purified IKK-alpha and IKK-beta in vitro. In contrast, the moieties of sulfasalazine, 5-aminosalicylic acid, and sulfapyridine or 4-aminosalicylic acid had no effect. Activation of extracellular signal-related kinase (ERK) 1 and 2, c-Jun-N-terminal kinase (JNK) 1, and p38 was unaffected by sulfasalazine. The decrease in substrate phosphorylation by IKK-alpha and -beta is associated with a decrease in autophosphorylation of IKKs and can be antagonized by excess adenosine triphosphate.

CONCLUSIONS

These data identify sulfasalazine as a direct inhibitor of IKK-alpha and -beta by antagonizing adenosine triphosphate binding. The suppression of NF-kappaB activation by inhibition of the IKKs contributes to the well-known anti-inflammatory and immunosuppressive effects of sulfasalazine.

摘要

背景与目的

核因子κB/Rel（NF-κB/Rel）的激活与炎症性肠病（IBD）的发病机制有关。用于治疗IBD的各种药物，如糖皮质激素、5-氨基水杨酸和柳氮磺胺吡啶，都会干扰NF-κB/Rel信号传导。本研究的目的是确定柳氮磺胺吡啶抑制NF-κB激活的分子机制。

方法

使用电泳迁移率变动分析、转染和免疫复合物激酶分析评估柳氮磺胺吡啶及其部分对NF-κB信号传导的影响。使用纯化的重组IKK-α和-β蛋白研究柳氮磺胺吡啶对IκB激酶（IKK）活性的直接作用。

结果

柳氮磺胺吡啶可剂量依赖性地抑制肿瘤坏死因子α、12-O-十四酰佛波醇-13-乙酸酯或NF-κB诱导激酶、IKK-α、IKK-β或组成型活性IKK-α和IKK-β突变体过表达所诱导的NF-κB/Rel活性。柳氮磺胺吡啶抑制肿瘤坏死因子α诱导的Jurkat T细胞和SW620结肠细胞中内源性IKK的激活，以及体外纯化的IKK-α和IKK-β的催化活性。相比之下，柳氮磺胺吡啶的部分、5-氨基水杨酸、磺胺吡啶或4-氨基水杨酸没有作用。细胞外信号调节激酶（ERK）1和2、c-Jun氨基末端激酶（JNK）1和p38的激活不受柳氮磺胺吡啶的影响。IKK-α和-β导致的底物磷酸化减少与IKK自身磷酸化的减少有关，并且可以被过量的三磷酸腺苷拮抗。