Stajnko Anja, Pineda Daniela, Klus Jonathan K, Love Tanzy M, Thurston Sally W, Mulhern Maria S, Strain J J, McSorley Emeir M, Myers Gary J, Watson Gene E, Shroff Emelyn, Shamlaye Conrad F, Yeates Alison J, van Wijngaarden Edwin, Broberg Karin
Department of Laboratory Medicine, Division of Occupational and Environmental Medicine, Lund University, Lund, Sweden.
School of Medicine and Dentistry, University of Rochester Medical Center, Rochester, New York, USA.
Environ Health Perspect. 2025 Feb;133(2):27002. doi: 10.1289/EHP14776. Epub 2025 Feb 4.
Telomere length (TL) and mitochondrial DNA copy number (mtDNAcn) variations are linked to age-related diseases and are associated with environmental exposure and nutritional status. Limited data, however, exist on the associations with mercury exposure, particularly early in life.
We examined the association between prenatal mercury (Hg) exposure and TL and mtDNAcn in 1,145 Seychelles children, characterized by a fish-rich diet.
Total mercury (THg) was determined in maternal hair at delivery and cord blood. TL and mtDNAcn were determined relative to a single-copy hemoglobin beta gene in the saliva of 7-y-old children. Linear regression models assessed associations between THg and relative TL (rTL) and relative mtDNAcn (rmtDNAcn) while controlling for maternal and cord serum polyunsaturated fatty acid (PUFA) status and sociodemographic factors. Interactions between THg and child sex, PUFA, and telomerase genotypes were evaluated for rTL and rmtDNAcn.
Higher THg concentrations in maternal hair and cord blood were associated with longer rTL [; 95% confidence interval (CI): 0.002, 0.016 and ; 95% CI: 0.001, 0.003, respectively], irrespective of sex, PUFA, or telomerase genotypes. Maternal serum n-6 PUFA and n-6/n-3 ratio were associated with shorter [; 95% CI: , and ; 95% CI: , , respectively] and PUFA with longer (; 95% CI: 0.032, 0.65) rTL. Cord blood n-6 PUFA was associated with longer (; 95% CI: 0.050, 0.26) rTL. Further analyses revealed linoleic acid in maternal blood and arachidonic acid in cord blood as the main drivers of the n-6 PUFA associations. No associations were observed for THg and PUFA with rmtDNAcn.
Our results indicate that prenatal THg exposure and PUFA status are associated with rTL later in childhood, although not consistently aligned with our initial hypothesis. Subsequent research is needed to confirm this finding, further evaluate the potential confounding of fish intake, and investigate the underlying molecular mechanisms to verify the use of rTL as a true biomarker of THg exposure. https://doi.org/10.1289/EHP14776.
端粒长度（TL）和线粒体DNA拷贝数（mtDNAcn）变异与年龄相关疾病有关，且与环境暴露和营养状况相关。然而，关于与汞暴露的关联，尤其是生命早期的关联，现有数据有限。
我们研究了1145名塞舌尔儿童产前汞（Hg）暴露与TL和mtDNAcn之间的关联，这些儿童以富含鱼类的饮食为特征。
在分娩时测定母亲头发和脐带血中的总汞（THg）。在7岁儿童的唾液中，相对于单拷贝血红蛋白β基因测定TL和mtDNAcn。线性回归模型评估THg与相对TL（rTL）和相对mtDNAcn（rmtDNAcn）之间的关联，同时控制母亲和脐带血清多不饱和脂肪酸（PUFA）状态及社会人口学因素。评估THg与儿童性别、PUFA和端粒酶基因型之间的相互作用对rTL和rmtDNAcn的影响。
母亲头发和脐带血中较高的THg浓度与较长的rTL相关[分别为；95%置信区间（CI）：0.002，0.016和；95%CI：0.001，0.003]，与性别、PUFA或端粒酶基因型无关。母亲血清n-6多不饱和脂肪酸和n-6/n-3比值与较短的[分别为；95%CI：，和；95%CI：，]rTL相关，而PUFA与较长的（；95%CI：0.032，0.65）rTL相关。脐带血n-6多不饱和脂肪酸与较长的（；95%CI：0.050，0.26）rTL相关。进一步分析显示，母亲血液中的亚油酸和脐带血中的花生四烯酸是n-6多不饱和脂肪酸关联的主要驱动因素。未观察到THg和PUFA与rmtDNAcn之间的关联。
我们的结果表明，产前THg暴露和PUFA状态与儿童后期的rTL相关，尽管并不完全符合我们最初的假设。需要后续研究来证实这一发现，进一步评估鱼类摄入的潜在混杂因素，并研究潜在的分子机制，以验证rTL作为THg暴露真实生物标志物的用途。https://doi.org/10.1289/EHP14776。
