Department of Family Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Department of Family Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.
Front Immunol. 2021 Apr 28;12:667460. doi: 10.3389/fimmu.2021.667460. eCollection 2021.
Studies have shown that cigarette smoke condensate stimulates monocytes to express toll-like receptor 4 (TLR4), tumor necrosis factor-α (TNF-α), and intercellular adhesion molecule 1 (ICAM-1), and enhances their adhesion to the endothelium. However, the same effects of cigarette smoking have not been explored . This study is to investigate the effect of cigarette smoking and smoking cessation on their mRNA expression in human peripheral blood mononuclear cells (PBMCs).
A group of 97 smokers and 62 nonsmokers were enrolled. The RNA from PBMCs was assessed with real-time polymerase chain reaction (PCR) to determine the levels of ICAM-1, TNF-α, and TLR4. The same markers in PBMCs of 87 quitters were examined before and at one week, one month, and two months after smoking cessation.
Of the 97 smokers, 85 (87.6%) were males, and 30 (48.4%) of the nonsmokers were males ( < 0.0001). The mean (SD) age of the smokers was 43.24 (10.89) years, which was younger than 43.45 (11.41) years of nonsmokers ( < 0.0001). The incidence of cardiovascular diseases was 13.4% in smokers, which was higher than 1.6% in nonsmokers ( < 0.05). Both ICAM-1 and TNF-α mRNA levels in PBMCs were higher among the smokers ( < 0.0001). In addition, TLR4 mRNA levels in PBMCs were statistically elevated in the smokers ( < 0.0001) comparing with those in the nonsmokers. The mRNA levels of TLR4 and TNF-α in PBMCs decreased in those who had quit smoking for 2 months ( < 0.0001).
ICAM-1, TNF-α, and TLR4 mRNA expression levels in PBMCs increased in smokers and decreased after being on a smoking cessation program for 2 months. This finding suggested that TLR4 expression may mediate the atherogenic inflammatory process induced by smoking.
研究表明，香烟烟雾冷凝物可刺激单核细胞表达 toll 样受体 4（TLR4）、肿瘤坏死因子-α（TNF-α）和细胞间黏附分子 1（ICAM-1），并增强其与内皮细胞的黏附。然而，香烟烟雾的相同作用尚未得到探索。本研究旨在探讨吸烟和戒烟对人外周血单核细胞（PBMC）中这些 mRNA 表达的影响。
招募了一组 97 名吸烟者和 62 名非吸烟者。使用实时聚合酶链反应（PCR）评估 PBMC 中的 RNA，以确定 ICAM-1、TNF-α 和 TLR4 的水平。在 87 名戒烟者戒烟前、戒烟后 1 周、1 个月和 2 个月时，检查其 PBMC 中的相同标志物。
在 97 名吸烟者中，85 名（87.6%）为男性，30 名（48.4%）非吸烟者为男性（<0.0001）。吸烟者的平均（SD）年龄为 43.24（10.89）岁，小于非吸烟者的 43.45（11.41）岁（<0.0001）。吸烟者患心血管疾病的发生率为 13.4%，高于非吸烟者的 1.6%（<0.05）。PBMC 中 ICAM-1 和 TNF-α mRNA 水平在吸烟者中均升高（<0.0001）。此外，与非吸烟者相比，PBMC 中 TLR4 mRNA 水平在吸烟者中统计学上升高（<0.0001）。戒烟 2 个月后，PBMC 中 TLR4 和 TNF-α 的 mRNA 水平下降（<0.0001）。
吸烟者 PBMC 中 TLR4、TNF-α 和 ICAM-1 mRNA 表达水平升高，戒烟 2 个月后降低。这一发现表明，TLR4 表达可能介导吸烟引起的致动脉粥样硬化炎症过程。
