NF-κB介导MRP8/14诱导的人肺泡上皮A549细胞凋亡

 目的: 探讨髓样相关蛋白8/14(MRP8/14)对人肺泡上皮A549细胞存活及凋亡的影响,并研究核因子κB(NF-κB)在其中的作用。方法: MRP8/14以不同剂量或刺激时间处理A549细胞,CCK-8法检测其对细胞活力的影响;流式细胞术检测细胞凋亡率;Western blot法及间接免疫荧光法检测A549细胞内NF-κB p65蛋白核移位情况;Western blot法检测NF-κB p65蛋白磷酸化水平;使用NF-κB特异性抑制剂Bay 11-7082探讨NF-κB在凋亡过程中的作用。结果: MRP8/14能以剂量和时间依赖的方式影响A549细胞的存活(P<0.05),流式细胞技术检测结果表明MRP8/14处理后A549细胞凋亡率明显增加(P<0.01)。此外,MRP8/14能够诱导NF-κB p65蛋白发生显著磷酸化,并移位至细胞核中,NF-κB信号通路明显激活,而NF-κB特异性抑制剂Bay 11-7082能够明显抑制MRP8/14诱导的细胞凋亡(P<0.01)。结论: NF-κB在MRP8/14所导致的肺泡上皮细胞凋亡过程发挥了重要作用。

NF-κB regulates apoptosis of human alveolar epithelial cells induced by MRP8/14

AIM: To investigate the effects of myeloid-related protein 8/14(MRP8/14) on the survival and apoptosis of human alveolar epithelial cell line A549, and to explore the role of nuclear factor-κB(NF-κB) in this process. METHODS: A549 cells were treated with different doses of MRP8/14 or stimulated with MRP8/14 for different time. The effect of MRP8/14 on the viability of A549 cells was determined by CCK-8 assay. The apoptotic rates were tested by flow cytometry. The nuclear translocation of NF-κB p65 was detected by Western blot and indirect immunofluorescence. Besides, the phosphorylation level of NF-κB p65 was determined by Western blot. NF-κB-specific inhibitor Bay 11-7082 was used to further analyze the role of NF-κB in the apoptosis induced by MRP8/14. RESULTS: The viability of the A549 cells was affected by MRP8/14 in a dose-and time-dependent manner. Flow cytometric analysis showed that the apoptotic rates were increased in the cells treated with MRP8/14(P<0.01). In A549 cells administered with MRP8/14, NF-κB p65 was significantly phosphorylated and translocated into the nuclei, suggesting the activation of NF-κB signaling pathway. However, NF-κB-specific inhibitor Bay 11-7082 significantly attenuated the cell apoptosis induced by MRP8/14(P<0.01). CONCLUSION: NF-κB plays an important role in regulating the apoptosis of human alveolar epithelial cells induced by MRP8/14.