Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, Office of Research and Development, U.S. Environmental Protection Agency, Chapel Hill, North Carolina.
Institute of Epidemiology, Helmholtz München, Neuherberg, Germany.
Ann Am Thorac Soc. 2022 Apr;19(4):583-593. doi: 10.1513/AnnalsATS.202107-767OC.
Exposure to air pollution is associated with adverse respiratory effects. Polyunsaturated omega 3 (n-3) fatty acids (FAs) appear to attenuate the health effects of air pollution. This panel study evaluated whether n-3 FA intake and blood levels of polyunsaturated omega 6 (n-6) FAs can modulate the associations between respiratory effects and short-term exposure to ambient air pollution in healthy adults. Sixty-two healthy adults were enrolled into either high or low n-3 FA groups on the basis of n-3 FA intake and erythrocyte n-3 FA concentrations. Low and high n-6 FA groups were dichotomized on the basis of blood n-6 FA levels. Participants underwent three to five testing sessions separated by at least 7 days. At each session, the forced vital capacity (FVC), forced expiratory volume in 1 second (FEV), and plasma markers of inflammation (IL-6 [interleukin-6]) and oxidative stress (ox-LDL [oxidized low-density lipoprotein]) were measured. Associations between the ambient ozone and fine particulate matter (PM) (PM with an aerodynamic diameter ⩽2.5 μm [PM]) levels and the lung function and blood markers were assessed by using mixed-effect models stratified by FA levels. Average levels of ozone (40.8 ± 11.1 ppb) and PM (10.2 ± 4.1 μg/m) were below national ambient air quality standards during the study period. FVC was positively associated with ozone at a lag of 0 days (lag0) in the high n-3 FA group, whereas the association was null in the low n-3 FA group (for an interquartile range increase in ozone of 1.8% [95% confidence interval (CI): 0.5% to 3.2%] vs. 0.0% [95% CI: -1.4% to 1.5%]); however, the association shifted to being negative at lag4 (-1.9% [95% CI: -3.2 to -0.5] vs. 0.2% [95% CI: -1.2% to 1.5%]) and lag5 (-1.2% [95% CI: -2.4% to 0.0%] vs. 0.9% [95% CI: -0.4% to 2.3%]). A similar pattern was observed in the low n-6 FA group compared with the high n-6 FA group (lag0: 1.7% [95% CI: 0.3% to 3.0%] vs. 0.5% [95% CI: -0.9% to 2.0%] and lag4: -1.4% [95% CI: -2.8% to 0.0%] vs. -0.5% [95% CI: -1.8% to 0.9%]). The associations between FEV and ozone and between FVC and PM also followed a similar pattern. Elevated ozone levels were associated with an immediate decrease in ox-LDL in the high n-3 FA group at lag0 (-12.3% [95% CI: -24.8% to 0.1%]), whereas there was no change in the low n-3 FA group (-7.5% [95% CI: -21.4% to 6.5%]) and there was a delayed increase in IL-6 in the high n-3 FA group compared with the low n-3 FA group (lag4: 66.9% [95% CI: 27.9% to 106.0%] vs. 8.9% [95% CI: -31.8% to 49.6%], lag5: 58.2% [95% CI: 22.4% to 94.1%] vs. -7.4% [95% CI: -48.8% to 34.0%], and lag6: 45.8% [95% CI: 8.7% to 82.9%] vs. -8.5% [95% CI: -49.7% to 32.6%]). We observed lag-dependent associations between short-term ambient air pollutants and lung function that were differentially modulated by n-3 and n-6 FAs, suggesting that n-3 and n-6 FAs counteract the respiratory response to low levels of ambient air pollution in healthy adults.Clinical trial registered with clinicaltrials.gov (NCT02921048).
暴露于空气污染与不良的呼吸道效应有关。多不饱和 omega-3（n-3）脂肪酸（FA）似乎可以减轻空气污染对健康的影响。本队列研究评估了 n-3 FA 摄入量和血液中多不饱和 omega-6（n-6）FA 水平是否可以调节健康成年人短期暴露于环境空气中污染物与呼吸道效应之间的关联。62 名健康成年人根据 n-3 FA 摄入量和红细胞 n-3 FA 浓度被分为高或低 n-3 FA 组。根据血液 n-6 FA 水平将低和高 n-6 FA 组分为两组。参与者在至少 7 天的时间内进行了三到五次测试。在每次测试中，测量了用力肺活量（FVC）、1 秒用力呼气量（FEV）以及血浆炎症标志物（白细胞介素-6 [IL-6]）和氧化应激标志物（氧化低密度脂蛋白 [ox-LDL]）。使用混合效应模型，根据 FA 水平分层评估环境臭氧和细颗粒物（PM）（空气动力学直径 ⩽2.5μm 的 PM [PM]）水平与肺功能和血液标志物之间的关联。在研究期间，臭氧（40.8 ± 11.1 ppb）和 PM（10.2 ± 4.1 μg/m）的平均水平均低于国家环境空气质量标准。在高 n-3 FA 组中，FVC 与臭氧在滞后 0 天（lag0）呈正相关，而在低 n-3 FA 组中无相关性（臭氧每增加 1 个四分位距为 1.8%[95%置信区间（CI）：0.5%至 3.2%]与 0.0%[95%CI：-1.4%至 1.5%]）；然而，在滞后 4 天（-1.9%[95%CI：-3.2 至-0.5]与 0.2%[95%CI：-1.2%至 1.5%]）和滞后 5 天（-1.2%[95%CI：-2.4%至 0.0%]与 0.9%[95%CI：-0.4%至 2.3%]）时呈负相关。与高 n-6 FA 组相比，低 n-6 FA 组也观察到类似的模式（lag0：1.7%[95%CI：0.3%至 3.0%]与 0.5%[95%CI：-0.9%至 2.0%]和 lag4：-1.4%[95%CI：-2.8%至 0.0%]与-0.5%[95%CI：-1.8%至 0.9%]）。FEV 和臭氧之间以及 FVC 和 PM 之间的关联也遵循类似的模式。臭氧水平升高与高 n-3 FA 组在滞后 0 天 ox-LDL 立即下降有关（-12.3%[95%CI：-24.8%至 0.1%]），而低 n-3 FA 组无变化（-7.5%[95%CI：-21.4%至 6.5%]），并且与低 n-3 FA 组相比，高 n-3 FA 组在滞后 4 天和滞后 5 天 ox-LDL 水平增加（lag4：66.9%[95%CI：27.9%至 106.0%]与 8.9%[95%CI：-31.8%至 49.6%]，lag5：58.2%[95%CI：22.4%至 94.1%]与-7.4%[95%CI：-48.8%至 34.0%]，lag6：45.8%[95%CI：8.7%至 82.9%]与-8.5%[95%CI：-49.7%至 32.6%]）。我们观察到短期环境空气污染物与肺功能之间存在滞后相关的关联，这些关联受 n-3 和 n-6 FA 的差异调节，表明 n-3 和 n-6 FA 可以抵消健康成年人对低水平环境空气污染的呼吸道反应。这项临床试验在 clinicaltrials.gov （NCT02921048）注册。
