包括课题组前期研究在内的大量证据已表明，大气污染物和绿地暴露与成人血压水平存在关联。但是，母亲孕期PM1和绿地暴露对新生儿血压影响的研究尚缺乏，且潜在机制不清楚。因此，本项目拟基于我们已在广东省四城市建立的出生队列，招募1138名孕妇作为研究对象，分别在孕早、中和晚期进行随访，跟踪至分娩结束，测量并记录新生儿血压等结局。基于机器学习算法、卫星遥感影像以及问卷信息精确评估母亲孕期PM1和绿地个体暴露水平。采集脐带血、胎盘组织和新生儿尿液等生物样本，检测9种反映炎症/氧化应激的指标和7种反映自主神经系统平衡性的指标。综合以上信息，评估孕期PM1和绿地暴露对新生儿血压的影响；阐明绿地对PM1暴露致血压升高效应的减缓作用及其模式；并进一步探讨炎症/氧化应激和自主神经系统调节在孕期PM1和绿地暴露影响新生儿血压中的作用机理。本项目将为大气污染防控、城市绿地规划和高血压早期预防提供理论依据。

A large body of evidence, including our previous findings, has documented the relationships of exposure to ambient air pollution and greenness with blood pressure levels in adults. However, evidence concerning the associations of prenatal PM1 and greenness exposures with newborn blood pressure levels is limited, and the potential mechanisms underlying the associations remain unclear. Therefore, the objective of this project is to fill this void in the research literature by performing a birth cohort study. We will recruit 1138 pregnant women in the first trimester of pregnancy from 4 cities of Guangdong province, and follow-up them until birth to collect data on antenatal care and newborn blood pressure. Individual prenatal PM1 exposure will be assessed by combining objective PM1 prediction from a spatial statistical model (machine learning method) and outdoor exercise time. Individual prenatal greenness exposure will be assessed by combining calculations based on satellite images and information on greenspace use. We will collect cord blood, placenta, and urine samples of newborns for determining 9 inflammatory/oxidative stress biomarkers as well as 7 autonomic nervous system biomarkers. We propose to (1) assess the associations of prenatal exposures to PM1 and greenness with newborn blood pressure levels; (2) clarify whether greenness exposure reduces blood pressure via lowering air pollution or via interacting with air pollution; and (3) explore whether elevated systematic inflammation/oxidative stress and autonomic nervous system imbalance are involved in the pathways by which prenatal PM1 and greenness exposures affecting newborn blood pressure. Findings from this study would provide theoretical evidence for developing strategies for air pollution control, urban greenspace planning, and early hypertension prevention.