Department of Anatomy and Cell Biology, The Rappaport Faculty of Medicine, Technion, Haifa, Israel.
Anticancer Res. 2011 May;31(5):1607-17.
Peroxynitrite has been proposed to activate Nuclear Factor κappa beta (NF-κB) in a non-canonical or aberrant pathway and to contribute to pathology of many diseases.
The activation of NF-κB by peroxynitrite was assessed by Western blot, immunoprecipitation, RT-PCR, and image stream analysis.
Our work showed that in HT-29 cancer cells, peroxynitrite can cause nitration of Inhibitory protein kappa B alpha (IκBα) at the expense of its phosphorylation. This led to a decrease in the degradation and re-synthesis of IκBα. Similar findings were observed for mRNA levels assessed by RT-PCR. Exposure of HT-29 cells to p38 inhibitor SB202190, prior to stimulation, resulted in a dramatic decrease of IκBα kinase and IκBα phosphorylation and caused an increase of peroxynitrite-mediated nitration of IκBα, indicating that peroxynitrite may activate NF-κB via dual mechanism of IκBα phosphorylation which is p38 dependent, as well as IκBα nitration.
Our findings demonstrate a possible interaction of the p38 pathway with the NF-κB pathway under peroxynitrite stimulation.
过氧亚硝酸盐已被提出通过非经典或异常途径激活核因子 κappa beta（NF-κB），并导致许多疾病的病理学发生。
通过 Western blot、免疫沉淀、RT-PCR 和图像流分析评估过氧亚硝酸盐对 NF-κB 的激活作用。
我们的工作表明，在 HT-29 癌细胞中，过氧亚硝酸盐可以导致抑制蛋白 kappa B alpha（IκBα）的硝化，而牺牲其磷酸化。这导致 IκBα 的降解和再合成减少。通过 RT-PCR 评估的 mRNA 水平也观察到了类似的发现。在刺激之前，用 p38 抑制剂 SB202190 预先处理 HT-29 细胞，导致 IκBα 激酶和 IκBα 磷酸化的急剧减少，并导致过氧亚硝酸盐介导的 IκBα硝化增加，表明过氧亚硝酸盐可能通过 IκBα 磷酸化的双机制（p38 依赖性）以及 IκBα 硝化来激活 NF-κB。
我们的发现表明，在过氧亚硝酸盐刺激下，p38 途径与 NF-κB 途径之间可能存在相互作用。
