Stenz Ludwig, Escoffier Jessica, Rahban Rita, Nef Serge, Paoloni-Giacobino Ariane
Department of Genetic Medicine and Development, University of Geneva Faculty of Medicine, Geneva, Switzerland.
Swiss Centre for Applied Human Toxicology, Basel, Switzerland.
PLoS One. 2017 Jan 13;12(1):e0170441. doi: 10.1371/journal.pone.0170441. eCollection 2017.
The endocrine disruptor bis(2-ethylhexyl) phthalate (DEHP) has been shown to exert adverse effects on the male animal reproductive system. However, its mode of action is unclear and a systematic analysis of its molecular targets is needed. In the present study, we investigated the effects of prenatal exposure to 300 mg/kg/day DEHP during a critical period for gonads differentiation to testes on male mice offspring reproductive parameters, including the genome-wide RNA expression and associated promoter methylation status in the sperm of the first filial generation. It was observed that adult male offspring displayed symptoms similar to the human testicular dysgenesis syndrome. A combination of sperm transcriptome and methylome data analysis allowed to detect a long-lasting DEHP-induced and robust promoter methylation-associated silencing of almost the entire cluster of the seminal vesicle secretory proteins and antigen genes, which are known to play a fundamental role in sperm physiology. It also resulted in the detection of a DEHP-induced promoter demethylation associated with an up-regulation of three genes apparently not relevant for sperm physiology and partially related to the immune system. As previously reported, DEHP induced an increase in mir-615 microRNA expression and a genome-wide decrease in microRNA promoter methylation. A functional analysis revealed DEHP-induced enrichments in down-regulated gene transcripts coding for peroxisome proliferator-activated receptors and tumor necrosis factor signaling pathways, and in up-regulated gene transcripts coding for calcium binding and numerous myosin proteins. All these enriched pathways and networks have been described to be associated in some way with the reproductive system. This study identifies a large new array of genes dysregulated by DEHP that may play a role in the complex system controlling the development of the male reproductive system.
内分泌干扰物邻苯二甲酸二（2-乙基己基）酯（DEHP）已被证明会对雄性动物生殖系统产生不利影响。然而，其作用模式尚不清楚，需要对其分子靶点进行系统分析。在本研究中，我们调查了在性腺分化为睾丸的关键时期，孕期暴露于300 mg/kg/天DEHP对雄性小鼠后代生殖参数的影响，包括第一代子代精子中的全基因组RNA表达及相关启动子甲基化状态。观察到成年雄性后代表现出与人类睾丸发育不全综合征相似的症状。精子转录组和甲基化组数据分析相结合，能够检测到DEHP诱导的、几乎整个精囊分泌蛋白和抗原基因簇的持久且强烈的启动子甲基化相关沉默，这些基因在精子生理学中起着重要作用。这还导致检测到DEHP诱导的启动子去甲基化，与三个明显与精子生理学无关且部分与免疫系统相关的基因上调有关。如先前报道，DEHP诱导mir-615微小RNA表达增加以及全基因组微小RNA启动子甲基化减少。功能分析显示，DEHP诱导编码过氧化物酶体增殖物激活受体和肿瘤坏死因子信号通路的下调基因转录本富集，以及编码钙结合蛋白和众多肌球蛋白蛋白的上调基因转录本富集。所有这些富集的通路和网络都已被描述为在某种程度上与生殖系统相关。本研究鉴定出大量受DEHP失调的新基因阵列，它们可能在控制雄性生殖系统发育的复杂系统中发挥作用。
