Associations of maternal exposure to 41 metals/metalloids during early pregnancy with the risk of spontaneous preterm birth: Does oxidative stress or DNA methylation play a crucial role?

Environment International

Xin Meng¹  Hang An¹  Jicheng Gong²  Aiguo Ren²  Le Zhang²  Rongwei Ye³  Bin Wang³  Zhiwen Li³  Ruiwei Xu⁴  Yiming Pang⁴ 

[1] Center for Environment and Health, Peking University, Beijing 100871, China;Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, China;Institute of Reproductive and Child Health, Peking University/Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing 100191, China;SKL-ESPC, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China;

关键词: Multiple types of metals/metalloids;    Spontaneous preterm birth;    Oxidative stress;    DNA methylation;    Early pregnancy;   

DOI  :  

来源: DOAJ

【 摘 要 】

Background: Few studies have explored the effects of multiple types of metals/metalloids on spontaneous preterm birth (SPB). A nested case–control study was conducted in Shanxi Province to investigate the associations between maternal exposure to 41 metals/metalloids during early pregnancy and the risk of SPB, and to clarify the underlying mechanisms of oxidative stress and DNA methylation. Methods: A total of 74 controls with full-term delivery and 74 cases with SPB were included in the nested case–control study. The metals/metalloids in serum and the DNA adducts in peripheral blood cell DNA were determined using ICP-MS and UPLC-QqQ-MS/MS, respectively. Unconditional logistic regression models were employed to estimate the associations of the risk of SPB with the metal concentrations, as well as with the levels of oxidative stress/DNA methylation. In addition, linear regression models were used to investigate the associations between the metal/metalloid concentrations and the levels of oxidative stress/DNA methylation. Results: After adjusting for potential confounders, the concentrations of Mn, Fe, Cu, Nd, Hg, and Pb in maternal serum during early pregnancy were positively associated with the risk of SPB. Compared with the lowest levels (Quartile 1) of Mn, Fe, Cu, Nd, Hg, and Pb, the odds ratios of SPB increased to 5.21 (95% CI: 1.63, 16.68), 3.47 (95% CI: 1.07, 11.21), 16.23 (95% CI: 3.86, 68.18), 10.54 (95% CI: 2.79, 39.86), 5.88 (95% CI: 1.72, 20.11), and 4.09 (95% CI: 1.31, 12.77) in the highest levels (Quartile 4), respectively. A significant increase in 8-OHdG was associated with the increased exposure to Fe, Pr, Eu, Er, and Lu. The levels of 5-MdC, 5-HmdC, and N6-MdA—the indicators of DNA methylation—were associated with exposure to multiple metals/metalloids. However, no significant associations were observed between the levels of oxidative stress or DNA methylation and the risk of SPB. Conclusions: Exposure to multiple types of metals/metalloids during early pregnancy is positively associated with the risk of SPB. Oxidative stress and DNA methylation are significantly associated with exposure to multiple metals/metalloids. Systemic oxidative stress and DNA methylation have not been proven to be the mediating mechanisms of metals increasing the risk of SPB.

【 授权许可】

Unknown