Kontny E, Szczepańska K, Kowalczewski J, Kurowska M, Janicka I, Marcinkiewicz J, Maśliński W
Institute of Rheumatology, Warsaw, Poland.
Arthritis Rheum. 2000 Oct;43(10):2169-77. doi: 10.1002/1529-0131(200010)43:10<2169::AID-ANR4>3.0.CO;2-#.
Taurine chloramine (Tau-Cl) has been shown to inhibit the production of proinflammatory cytokines (interleukin-6 [IL-6] and IL-8) by fibroblast-like synoviocytes (FLS) isolated from rheumatoid arthritis (RA) patients. The present study was conducted to elucidate the mechanism of inhibitory action exerted by Tau-Cl.
The effects of Tau-Cl on 1) the transcription of genes coding for IL-6 and IL-8, and 2) the activity of nuclear factor kappaB (NF-kappaB) and activator protein 1 (AP-1) transcription factors, which are crucial for the transcription of these cytokine genes, were investigated in FLS isolated from the synovial tissue of RA patients. FLS were cultured in vitro for 3-6 passages and stimulated with recombinant human IL-1beta (1 ng/ml) in the presence of either Tau or Tau-Cl, which were added simultaneously with the stimulus at concentrations of 250 microM or 500 microM. The relative expression of IL-6 and IL-8 messenger RNA (mRNA) was evaluated after 4 hours of stimulation, using competitive reverse transcriptase-polymerase chain reaction. The DNA binding activity of NF-kappaB and AP-1 was examined 30 minutes and 2 hours after cell stimulation, respectively, using electromobility gel shift assay.
IL-1beta triggered a significant rise in the activity of transcription factors NF-kappaB and AP-1, followed by an elevation of cytokine IL-6 and IL-8 mRNA expression. Tau-Cl, but not Tau, reduced IL-1beta-triggered cytokine mRNA expression, exerting stronger inhibitory activity on the levels of IL-6 than on those of IL-8. Importantly, Tau-Cl also diminished the activity of NF-kappaB and, to a lesser extent, that of AP-1 transcription factor. Neither IL-1beta nor Tau-Cl affected the activity of octamer transcription factor 1.
Tau-Cl inhibition of IL-6 and IL-8 synthesis in FLS from RA patients results from the ability of this compound to diminish the activity of the major transcriptional regulators (NF-kappaB and AP-1), which subsequently reduces the transcription of these cytokine genes.
已证明氯胺牛磺酸（Tau-Cl）可抑制从类风湿性关节炎（RA）患者分离出的成纤维样滑膜细胞（FLS）产生促炎细胞因子（白细胞介素-6 [IL-6] 和IL-8）。本研究旨在阐明Tau-Cl发挥抑制作用的机制。
在从RA患者滑膜组织分离出的FLS中，研究Tau-Cl对以下两方面的影响：1）编码IL-6和IL-8的基因转录；2）核因子κB（NF-κB）和激活蛋白1（AP-1）转录因子的活性，这两种转录因子对这些细胞因子基因的转录至关重要。FLS在体外培养3至6代，并在存在牛磺酸（Tau）或Tau-Cl的情况下，用重组人IL-1β（1 ng/ml）进行刺激，Tau或Tau-Cl在刺激时同时添加，浓度分别为250 μM或500 μM。刺激4小时后，使用竞争性逆转录聚合酶链反应评估IL-6和IL-8信使核糖核酸（mRNA）的相对表达。分别在细胞刺激后30分钟和2小时，使用电泳迁移率凝胶迁移试验检测NF-κB和AP-1的DNA结合活性。
IL-1β引发转录因子NF-κB和AP-1的活性显著升高，随后细胞因子IL-6和IL-8的mRNA表达升高。Tau-Cl而非Tau降低了IL-1β引发的细胞因子mRNA表达，对IL-6水平的抑制活性强于对IL-8水平的抑制活性。重要的是，Tau-Cl还降低了NF-κB的活性，并在较小程度上降低了AP-1转录因子的活性。IL-1β和Tau-Cl均未影响八聚体转录因子1的活性。
Tau-Cl抑制RA患者FLS中IL-6和IL-8的合成，是因为该化合物能够降低主要转录调节因子（NF-κB和AP-1）的活性，进而减少这些细胞因子基因的转录。
