短期雾霾刺激对健康成年人鼻腔炎性反应状态的影响

摘要

Objective To investigate the impact of short-term severe air pollution on the nasal function and inflammation status of young healthy residents.Methods Twenty-three young healthy adults living in downtown Beijing were recruited.The self-reported nasal symptoms,nasal patency,upper and lower respiratory tract nitric oxide (NO) and inflammatory cytokines in the nasal secretions of each participant were recorded before and after severe air pollution which lasted for five days.Results At the second visit,different percentage of participants claimed slight symptoms of nasal congestion,irritation,dryness or postnasal drip.Accordingly,rhinometry and rhinomanometry examination showed that nasal airway resistance increased significantly,while nasal cavity volume and minimum crosssectional area decreased significantly.Both nasal NO and exhaled NO increased after severe air pollution.In nasal secretion,Th2-type cytokines eotaxin,and interleukin-5 (IL-5),chemokine (C-C motif) ligand 7,and pro-inflammatory cytokine IL-8 increased significantly after severe air pollution,Thl-type cytokine interferon-γ (IFN-γ) as well as immunoregulatory cytokines IL-10 and transforming growth factor (TGF-β) decreased significantly.Conclusion By means of promoting the Th2-predominant immune reaction and suppressing the regulatory immune response,exposure to short-term air pollution predisposes healthy adults to nasal inflammation,especially allergic nasal inflammation.%目的 观察短期重度雾霾对健康成年受试者鼻部症状、功能和炎性反应状态的影响.方法 23例居住于北京市中心的健康成年志愿者参与本项研究.分别于一次持续5d的雾霾前后记录受试者的鼻部不适症状、检查其鼻功能、口鼻呼出一氧化氮(nitric oxide,NO)浓度,并收集鼻分泌物用于细胞因子浓度测定.结果 在雾霾发生后的第二次访视中,受试者反映有不同程度的鼻部不适感,包括鼻堵、鼻痒、鼻干和鼻后滴漏等.鼻功能检查示鼻阻力由雾霾前的(0.18±0.01)Pa/(cm3·s)升高至雾霾后的(0.24 ±0.02)Pa/(cm3-s)(P=0.001);鼻腔容积由雾霾前的(15.06±052) cm3下降至雾霾后的(7.79±0.74) cm3(P=0.000);鼻腔最小截面积由雾霾前的(1.20±0.05) cm2下降至雾霾后的(1.06±0.04) cm2,差异有统计学意义(P =0.006).与雾霾发生前相比较,经鼻或经口呼出NO浓度均在雾霾发生后明显升高.雾霾后,鼻分泌物中的Th2型细胞因子eotaxin和白细胞介素-5(interleukin-5,IL-5)、趋化因子C-C-基元配体7[chemokine(C-C motif) ligand 7,CCL7]、以及促炎性反应因子IL-8浓度显著升高,而Thl型细胞因子干扰素(interferon-γ,IFN-γ)以及免疫调节因子IL-10和转化生长因子-β(transforming growth factor-β,TGF-β)浓度显著下降.结论 短期雾霾刺激可使健康成年人的鼻腔分泌物炎性反应介质倾向于Th2型分化,而参与免疫调节、抑制细胞增生、促进细胞外基质形成和损伤修复的细胞因子表达下降.鼻黏膜局部炎性反应状态的失衡一方面可直接使鼻腔有效通气面积减少,引发鼻部症状,另一方面可使个体易受过敏原、病原体或其他理化刺激的影响,这也是未来的研究方向.