Chen Shuya, Wang Xuedong, Yan Jin, Wang Zejun, Qian Qiuhui, Wang Huili
School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China.
School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China.
Sci Total Environ. 2023 Nov 25;901:165953. doi: 10.1016/j.scitotenv.2023.165953. Epub 2023 Aug 1.
As a typically anthropogenic contaminant, the toxicity effects of triclosan (TCS) were investigated in-depth from the viewpoint of mA-pre-miRNAs modification. Based on miRNAs high-throughput sequencing, we unravelled the underlying molecular mechanisms regarding TCS-induced lipid-metabolism functional disorders. TCS exposure caused severe lipid accumulation in 120 hpf zebrafish liver and reduced their locomotor activity. Both bioinformatics analysis and experimental validation verified that TCS targeted miR-27b up-regulation to further trigger lipid-metabolism disorders and developmental malformations, including shortened body length, yolk cysts, curved spine and delayed yolk absorption. TCS exposure and miR-27b upregulation both caused the enhanced levels of triglyceride and total cholesterol. Knockdown and overexpression of miR-27b regulated the expression changes of several functional genes related to downstream lipid metabolism of miR-27b, and most downstream target genes of miR-27b were suppressed and enriched in the AMPK signaling pathway. The experiments of pathway inhibitors and agonists further evidenced that TCS caused lipid-metabolism disorders by suppressing the AMPK signaling pathway. In upstream of miR-27b, TCS decreased total mA-RNA level by targeting upregulation of demethylase and downregulation of methylase reader ythdf1. Molecular docking and ythdf1 siRNA interference further confirmed that TCS targeted the expression change of ythdf1. Under ythdf1 knockdown in upstream of miR-27b, both abnormal lipid metabolism and miR-27b upregulation highlighted that TCS-induced lipid-metabolism disorders were attributable to the decreasing mA-RNA methylation levels in vivo. These perspectives provide an innovative idea for prevention and treatment of the lipid metabolism-related diseases and these findings open a novel avene for TCS's risk assessment and early intervention of the contaminant.
作为一种典型的人为污染物，从mA-前体微小RNA（pre-miRNAs）修饰的角度深入研究了三氯生（TCS）的毒性效应。基于微小RNA高通量测序，我们揭示了TCS诱导脂质代谢功能障碍的潜在分子机制。TCS暴露导致120小时胚胎期斑马鱼肝脏中严重的脂质积累，并降低其运动活性。生物信息学分析和实验验证均证实，TCS靶向miR-27b上调，进而引发脂质代谢紊乱和发育畸形，包括体长缩短、卵黄囊肿、脊柱弯曲和卵黄吸收延迟。TCS暴露和miR-27b上调均导致甘油三酯和总胆固醇水平升高。miR-27b的敲低和过表达调节了与miR-27b下游脂质代谢相关的几个功能基因的表达变化，miR-27b的大多数下游靶基因在AMPK信号通路中受到抑制并富集。通路抑制剂和激动剂实验进一步证明，TCS通过抑制AMPK信号通路导致脂质代谢紊乱。在miR-27b的上游，TCS通过靶向去甲基化酶上调和甲基化阅读蛋白ythdf1下调来降低总mA-RNA水平。分子对接和ythdf1 siRNA干扰进一步证实TCS靶向ythdf1的表达变化。在miR-27b上游的ythdf1敲低情况下，异常的脂质代谢和miR-27b上调均表明TCS诱导的脂质代谢紊乱归因于体内mA-RNA甲基化水平的降低。这些观点为脂质代谢相关疾病的预防和治疗提供了创新思路，这些发现为TCS的风险评估和该污染物的早期干预开辟了一条新途径。
