School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China; Shanghai Key Laboratory of Meteorology and Health, Shanghai 200030, China.
Environ Pollut. 2017 Jun;225:450-455. doi: 10.1016/j.envpol.2017.02.068. Epub 2017 Mar 9.
The underlying mechanisms about the association between ambient fine particulate matter (PM) and lung function were unclear. Few epidemiological studies have evaluated the potential mediating effects of serum club cell secretory protein (Clara) (CC16), a biomarker of pulmonary epithelium integrity.
To evaluate the short-term effect of personal PM exposure on lung function and to explore the potential mediating role of CC16 in this effect.
We enrolled 36 healthy, nonsmoking college students for a panel study in Shanghai, China from December 17, 2014 to July 11, 2015. We measured personal and real-time exposure to PM for 72 h preceding each of four rounds of health examinations, including lung function test and serum CC16 measurement. We used linear mixed-effect models to examine the effects of PM on lung function and CC16 over various lag times. Furthermore, we analyzed the mediating effect of CC16 in the association between PM and lung function.
Average PM exposure ranged from 36 to 52 μg/m3 across different lag periods. PM exposure was negatively associated with lung function and positively associated with serum CC16 concentration. The effect of PM on CC16 occurred earlier than that on lung function. For instance, an interquartile range (IQR) increase in 0-2 h average exposure to PM was significantly associated with a 4.84% increase in serum CC16; and an IQR increase in 3-6 h average exposure to PM was significantly associated with a 1.08% decrease in 1-sec forced expiratory volume. These effects lasted up to 24 h after exposure. Increased serum CC16 contributed 3.9%-36.3% of the association between PM and impaired lung function.
Acute exposure to PM might induce an immediate decrease in lung function by virtue of the loss of pulmonary epithelium integrity.
环境细颗粒物（PM）与肺功能之间关联的潜在机制尚不清楚。少数流行病学研究评估了血清克拉拉细胞分泌蛋白（Clara）（CC16）作为肺上皮完整性生物标志物的潜在中介作用。
评估个人 PM 暴露对肺功能的短期影响，并探讨 CC16 在这种影响中的潜在中介作用。
我们在中国上海进行了一项面板研究，于 2014 年 12 月 17 日至 2015 年 7 月 11 日期间招募了 36 名健康、不吸烟的大学生。我们在四次健康检查前的 72 小时内，测量了个人和实时 PM 暴露情况，包括肺功能测试和血清 CC16 测量。我们使用线性混合效应模型，检验了 PM 对不同滞后时间下肺功能和 CC16 的影响。此外，我们分析了 CC16 在 PM 与肺功能之间关联中的中介作用。
不同滞后时间的平均 PM 暴露范围为 36-52μg/m3。PM 暴露与肺功能呈负相关，与血清 CC16 浓度呈正相关。PM 对 CC16 的影响早于对肺功能的影响。例如，0-2 小时平均暴露 PM 每增加一个四分位距（IQR），血清 CC16 增加 4.84%；3-6 小时平均暴露 PM 每增加一个 IQR，1 秒用力呼气量减少 1.08%。这些影响持续到暴露后 24 小时。血清 CC16 的增加解释了 PM 与肺功能受损之间关联的 3.9%-36.3%。
急性 PM 暴露可能通过肺上皮完整性的丧失导致肺功能立即下降。
