Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
Division of Occupational and Environmental Medicine, Department of Laboratory Medicine, Lund University , Lund, Sweden.
Environ Health Perspect. 2018 Feb 1;126(2):027001. doi: 10.1289/EHP1912.
It has been proposed that interactions between selenium and arsenic in the body may affect their kinetics and toxicity. However, it is unknown how the elements influence each other in humans.
We aimed to investigate potential interactions in the methylation of selenium and arsenic.
Urinary selenium (U-Se) and arsenic (U-As) were measured using inductively coupled plasma mass spectrometry (ICPMS) in samples collected from pregnant women (=226) in rural Bangladesh at gestational weeks (GW) 8, 14, 19, and 30. Urinary concentrations of trimethyl selenonium ion (TMSe) were measured by HPLC-vapor generation-ICPMS, as were inorganic arsenic (iAs), methylarsonic acid (MMA), and dimethylarsinic acid (DMA). Methylation efficiency was assessed based on relative amounts (%) of arsenic and selenium metabolites in urine. Genotyping for the main arsenite and selenium methyltransferases, AS3MT and INMT, was performed using TaqMan probes or Sequenom.
Multivariable-adjusted linear regression analyses indicated that %TMSe (at GW8) was positively associated with %MMA (β=1.3, 95% CI: 0.56, 2.0) and U-As, and inversely associated with %DMA and U-Se in producers of TMSe ( rs6970396 AG+AA, =74), who had a wide range of urinary TMSe (12-42%). Also, %TMSe decreased in parallel to %MMA during pregnancy, especially in the first trimester (-0.58 %TMSe per gestational week). We found a gene-gene interaction for %MMA (-interaction=0.076 for haplotype 1). In analysis stratified by genotype, the association between %MMA and both haplotypes 1 and 3 was stronger in women with the GG (TMSe nonproducers, 5th-95th percentile: 0.2-2%TMSe) vs. AG+AA genotype.
Our findings for Bangladeshi women suggest a positive association between urinary %MMA and %TMSe. Genes involved in the methylation of selenium and arsenic may interact on associations with urinary %MMA. https://doi.org/10.1289/EHP1912.
据提议，体内硒和砷的相互作用可能会影响它们的动力学和毒性。然而，目前尚不清楚这些元素在人体内如何相互影响。
我们旨在研究硒和砷甲基化过程中的潜在相互作用。
使用电感耦合等离子体质谱法（ICPMS）检测来自孟加拉国农村地区妊娠 8、14、19 和 30 周的孕妇（=226）的尿液中的硒（U-Se）和砷（U-As）。通过高效液相色谱-氢化物发生-电感耦合等离子体质谱法（HPLC-vapor generation-ICPMS）测量三甲基硒代离子（TMSe）的浓度，同时测量无机砷（iAs）、甲基砷酸（MMA）和二甲基砷酸（DMA）的浓度。基于尿液中砷和硒代谢物的相对含量（%）评估甲基化效率。使用 TaqMan 探针或 Sequenom 对主要亚砷酸盐和硒甲基转移酶 AS3MT 和 INMT 的基因型进行检测。
多变量调整线性回归分析表明，在 TMSe 生成者（rs6970396 AG+AA，=74）中，TMSe（在 GW8 时）与 MMA（β=1.3，95%CI：0.56，2.0）和 U-As 呈正相关，与 DMA 和 U-Se 呈负相关。此外，TMSe 随着妊娠时间的推移而与 MMA 一起下降，尤其是在妊娠早期（-0.58%TMSe/妊娠周）。我们发现 MMA 的基因-基因相互作用（-互作=0.076，单体型 1）。在按基因型分层的分析中，在 GG（TMSe 非生成者，第 5 至 95 百分位数：0.2-2%TMSe）而非 AG+AA 基因型的女性中，MMA 与两种单体型 1 和 3 的关联更强。
我们对孟加拉国女性的研究结果表明，尿液中 MMA 和 TMSe 的百分比之间存在正相关。参与硒和砷甲基化的基因可能在与尿液 MMA 的关联上存在相互作用。https://doi.org/10.1289/EHP1912.
