Unit of Metals and Health, Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm, Sweden.
International Center for Diarrheal Disease Research, GPO Box 128, Dhaka 1000, Bangladesh.
Environ Int. 2018 Dec;121(Pt 1):842-851. doi: 10.1016/j.envint.2018.10.018. Epub 2018 Oct 18.
Biomarker selenium concentrations vary greatly between studies. Concentrations in erythrocytes, urine, and hair vary even at similar plasma concentrations, suggesting that unknown factors influence the distribution of selenium between body compartments.
To assess predictors of the different selenium biomarkers in children.
We used a mother-child cohort, nested in a population-based supplementation trial in rural Bangladesh (MINIMat), established for evaluation of arsenic toxicity. Selenium was measured in plasma (n = 223), erythrocytes, urine, and hair at 9 years (n = 395) and in erythrocytes and urine at 4.5 years (n = 259) using inductively coupled plasma mass spectrometry. We also measured concentrations of arsenic (all biospecimen) and cadmium (erythrocytes and urine). Genotyping for INMT, a methyltransferase involved in selenium metabolism, was performed using TaqMan probes.
At 9 years, the selenium concentrations ranged 51-139 μg/L in plasma, 128-281 μg/L in erythrocytes, 2.2-55 μg/L in urine, and 258-723 μg/kg in hair. Correlations (r) between biomarkers ranged 0.12-0.37, and were strongest between blood compartments and between erythrocytes and hair (long-term markers). In multivariable-adjusted linear regression analyses, plasma selenium differed by sampling season (highest in food-secure pre-monsoon season) and was inversely associated with plasma arsenic (range < 0.0080-20 μg/L; B = -1.1, 95% CI: -1.8, -0.41). In contrast, erythrocyte selenium was positively associated with erythrocyte arsenic (range 0.95-50 μg/L; B = 0.58, 95% CI: 0.26, 0.91) and inversely associated with erythrocyte cadmium (range 0.27-3.1 μg/L; B = -12, 95% CI: -17, -6.9). These associations were similar at 4.5 years. Only selenium in hair and urine were influenced by INMT polymorphisms. Finally, chronic malnutrition seemed to increase selenium retention, measured as the ratio plasma/urinary selenium.
Selenium biomarkers seem to be influenced by malnutrition, genetics, and exposure to metal pro-oxidants. This might affect the evaluation of deficiency/sufficiency, normally assessed by selenium in plasma/serum.
生物标志物硒浓度在不同研究中差异很大。即使在相似的血浆浓度下，红细胞、尿液和头发中的浓度也存在差异，这表明未知因素影响着硒在体内各隔室之间的分布。
评估儿童中不同硒生物标志物的预测因素。
我们使用了一个母子队列，嵌套在孟加拉国农村进行的一项基于人群的补充试验（MINIMat）中，该试验旨在评估砷毒性。使用电感耦合等离子体质谱法在 9 岁时（n=395）和 4.5 岁时（n=259）测量血浆（n=223）、红细胞、尿液和头发中的硒含量，以及红细胞和尿液中的砷（所有生物样本）和镉含量。使用 TaqMan 探针进行与硒代谢有关的甲基转移酶（INMT）的基因分型。
9 岁时，血浆硒浓度范围为 51-139μg/L，红细胞硒浓度范围为 128-281μg/L，尿液硒浓度范围为 2.2-55μg/L，头发硒浓度范围为 258-723μg/kg。生物标志物之间的相关性（r）范围为 0.12-0.37，血液隔室之间以及红细胞与头发之间的相关性最强（长期标志物）。在多变量调整线性回归分析中，血浆硒因采样季节而异（食物充足的前季风季节最高），与血浆砷呈负相关（范围<0.0080-20μg/L；B=-1.1，95%CI：-1.8，-0.41）。相比之下，红细胞硒与红细胞砷呈正相关（范围 0.95-50μg/L；B=0.58，95%CI：0.26，0.91），与红细胞镉呈负相关（范围 0.27-3.1μg/L；B=-12，95%CI：-17，-6.9）。这些关联在 4.5 岁时相似。只有头发和尿液中的硒受到 INMT 多态性的影响。最后，慢性营养不良似乎会增加硒的保留率，表现为血浆/尿液中硒的比值。
硒生物标志物似乎受营养不良、遗传和暴露于金属促氧化剂的影响。这可能会影响通常通过血浆/血清中的硒来评估的缺乏/充足情况。
