Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa.
PLoS One. 2018 Oct 11;13(10):e0204400. doi: 10.1371/journal.pone.0204400. eCollection 2018.
The objective of this study was to identify potential mRNA expression changes in chicken livers associated with environmental exposure to dichloro-diphenyl-trichloroethane (DDT) and its metabolites (DDTs). In particular, we focused on genes relating to the immune system and metabolism. We analyzed liver samples from free-ranging chickens in KwaZulu-Natal, South Africa, for contamination by DDTs. This area predominantly uses DDT in its malaria control program, and homes are sprayed annually with the pesticide. Genes relating to the immune system and metabolism were selected as potential genetic biomarkers that could be linked to higher contamination with DDTs. RT-qPCR analysis on 39 samples showed strong correlations between DDTs contamination and mRNA expression for the following genes: AvBD1, AvBD2, AvBD6 and AvBD7 (down-regulated), and CYP17, ELOVL2 and SQLE (up-regulated). This study shows for the first time interesting and significant correlations between genetic material collected from environmentally-exposed chickens and mRNA expression of several genes involved in immunity and metabolism. These findings show the usefulness of analysis on field samples from a region with high levels of environmental contamination in detecting potential biomarkers of exposure. In particular, we observed clear effects from DDT contamination on mRNA expression of genes involved in immune suppression, endocrine-disrupting effects, and lipid dysregulation. These results are of interest in guiding future studies to further elucidate the pathways involved in and clinical importance of toxicity associated with DDT exposure from contaminated environments, to ascertain the health risk to livestock and any subsequent risks to food security for people.
本研究旨在鉴定与环境中二氯二苯三氯乙烷（DDT）及其代谢物（DDTs）暴露相关的鸡肝脏中潜在的 mRNA 表达变化。特别是，我们专注于与免疫系统和代谢相关的基因。我们分析了南非夸祖鲁-纳塔尔省自由放养鸡的肝脏样本，以确定其是否受到 DDT 的污染。该地区在其疟疾控制计划中主要使用 DDT，每年都会对房屋进行喷洒。选择与免疫系统和代谢相关的基因作为潜在的遗传生物标志物，这些标志物可能与更高水平的 DDT 污染有关。对 39 个样本进行的 RT-qPCR 分析显示，DDTs 污染与以下基因的 mRNA 表达之间存在强烈相关性：AvBD1、AvBD2、AvBD6 和 AvBD7（下调），以及 CYP17、ELOVL2 和 SQLE（上调）。本研究首次表明，从暴露于环境中的鸡中收集的遗传物质与参与免疫和代谢的几个基因的 mRNA 表达之间存在有趣且显著的相关性。这些发现表明，在检测暴露的潜在生物标志物方面，对高环境污染地区的田间样本进行分析是有用的。特别是，我们观察到 DDT 污染对参与免疫抑制、内分泌干扰和脂质失调的基因的 mRNA 表达产生了明显的影响。这些结果对于指导未来的研究具有重要意义，有助于进一步阐明与受污染环境中 DDT 暴露相关的毒性的相关途径及其临床重要性，以确定对牲畜的健康风险以及对人类的任何后续食品安全风险。
