Arsenic trioxide inhibites transgenic tumor necrosis factor-α promoter activity in vascular smooth muscle cells and THP-1 monocytes in vitro

三氧化二砷抑制血管平滑肌细胞及单核细胞肿瘤坏死因子-α启动子活性(英文)

Aim This study was to evaluate the effect of arsenic trioxide （As2O3） on the transgenic TNF-α promoter activity in cultured vascular smooth muscle cells （VSMCs） and THP-1 monocytes. Methods Human TNF-α promoter was constructed by reporter gene system and was transiently transfected into VSMCs and THP-1 in vitro. The promoter activity was tested by luciferase activity with or without LPS and Ang Ⅱ stimulation, before and after different dosage of As2O3 treatment. Results 1. TNF-α promoter effectively expressed in VSMCs and THP-1 compared with CMV promoter （58.3% and 80.9%, respectively）. Both LPS and Ang Ⅱ significantly up-regulated TNF-α promoter activity （P〈0.05）. 2. As2O3 significantly inhibited, both intact and LPS/Ang Ⅱ stimulated promoter activity, in a dose dependent manner （P〈0.05）, and in both cell type. Conclusion These results manifested that, the inhibition effect of As2O3 on the activity of human TNF-α promoter indicated its potential inhibition on pro-inflammatory cytokine genes expression at transcriptional level and its potential anti-inflammatory property in the cardiovascular system.

目的探讨三氧化二砷(As2O3)对血管平滑肌细胞(VSMCs)及THP-1单核细胞体外转染的TNF-α基因启动子活性的调控作用。方法利用虫荧光素酶(luciferase)报告基因系统,构建含有人类TNF-α基因启动子的质粒DNA,经阳离子脂质体转染体外培养的VSMCs及THP-1,以LPS及Ang II刺激并经不同浓度的As2O3处理后,通过检测luciferase的活性来观察启动子活性的变化。结果本实验发现:TNF-α启动子在VSMCs及THP-1中可高效稳定地表达,分别为阳性对照(CMV启动子)的58.3%和80.9%;而经LPS及Ang II刺激的VSMCs和THP-1中,TNF-α启动子活性呈现明显上调(P<0.05)。VSMCs中2-8ìmol·L-1、THP-1中1-4ìmol·L-1的As2O3对未受诱导的TNF-α启动子有抑制作用,更可显著抑制经LPS及Ang II刺激后上调表达的TNF-α启动子活性,并呈剂量依赖关系(P<0.05)。结论以上结果提示,As2O3对TNF-α启动子转录活性的抑制,提示其对促炎细胞因子在转录水平的潜在抑制作用及心血管系统中的潜在抗炎作用。