Epigenetic transgenerational effects of endocrine disruptors via female germ line

内分泌干扰物通过雌性生殖系的表观遗传跨代效应

基本信息

批准号：
8319319
负责人：
Mehmet Uzumcu
金额：
$ 19.38万
依托单位：
RUTGERS, THE STATE UNIV OF N.J.
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-08-12 至 2015-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8319319
关键词：
Aberrant DNA Methylation Address Adult Affect Aging Anxiety Apoptosis Behavior Breeding Chemical Exposure Child DNA Methylation DNA Methyltransferase DNA Modification Methylases DNA Sequence Development Disease susceptibility Dose Embryo Endocrine Disruptors Endogenous Retroviruses Environment Epigenetic Process Event Exhibits Exposure to Female Fertility Future Future Generations Gene Expression Gene Expression Profile Generations Genes Germ Cells Germ Lines Global Change Goals Gonadal structure H19 gene Health Health Care Costs Inbreeding Incidence Individual Knowledge Lead Life Link Mediating Mediator of activation protein Methods Methoxychlor Methylation Modeling Morphology Neonatal Onset of illness Oocytes Ovarian Ovary Ovulation Parents Partner in relationship Pathology Pattern Perinatal Exposure Periodicity Pesticides Phenotype Play Puberty Public Health Rattus Research Retrotransposon Reverse Transcriptase Polymerase Chain Reaction Risk Role Sex Ratio Testing Time TimeLine Tissues Toxic Environmental Substances Woman Women&apos s Role base beryllium trifluoride bisulfite demethylation density environmental stressor fetal folliculogenesis follow-up grandchild imprint in utero innovation male novel postnatal prevent programs reproductive reproductive function sex sperm cell vinclozolin

项目摘要

DESCRIPTION (provided by applicant): It is well established that exposure to environmental stressors or toxicants such as endocrine-disrupting chemicals (EDCs) during in utero and/or neonatal development can result in adult-onset diseases. Such detrimental changes have been linked to aberrant DNA methylation patterns as well as other epigenetic mechanisms. It is of great concern that recent studies have suggested that such disease susceptibilities can be transmitted via epigenetic mechanisms to subsequent generations that were never directly exposed to the EDCs. For example, testicular abnormalities were transmitted to F2-F4 generation males via the male germ line after in utero exposure to an EDC. However, these effects were found to be sex-specific since F2-F3 females exhibited milder phenotypes that required exposure of both parents to the EDC. In this proposal, our objective is to address the critical issue of whether the female germ line is involved in such transgenerational (TG) effects of EDC exposure. Methoxychlor (MXC) is an EDC that has actions mimicking those of many other EDCs in the environment and was shown to cause epigenetic changes in the gonad; it will therefore be used as a model EDC in this proposal. Our hypothesis is that exposure to MXC during the critical window of development, defined here as the period of gonad differentiation through oocyte epigenetic reprogramming, leads to TG effects in the ovary that are mediated by epigenetic changes in the oocyte. To test our hypothesis, the proposal has two interrelated but distinct specific aims: (1) Determine somatic TG epigenetic effects of MXC in the ovary of F3 generation following exposure of F1. F1-generation inbred female rats will be treated with 0, 20 5g/kg/day MXC, or 50-100 mg/kg/day MXC between E11 and PND7. These females will be bred with untreated males, and F2-F4 females will be generated. Initially, ovarian morphology and gene expression and fertility will be assessed only in the F3 females since observation of TG effects in F3 generation is the minimum requirement for establishing TG effects. Gene expression changes and global and gene-specific DNA methylation changes will be investigated using conventional methods as well as array-based approaches. (2) Investigate the epigenetic changes induced by MXC in F1/F2 oocytes that may lead to TG effects in F3. DNA methylation patterns in imprinted genes and parasitic DNA sequences such as retrotransposons in oocytes will be analyzed, as aberrant methylation patterns in these sequences can be pathogenic. Oocytic gene expression patterns will also be examined; any correlation between the changes in gene expression and DNA methylation will be elucidated. The proposed study will be the first to investigate the epigenetic TG effects of EDCs transmitted via the female germ line beyond the F2 generation. We recognize the considerable risk associated with this study, but implications to the health of present and future generations are significant given the widespread presence of EDCs in the environment. A mechanistic understanding of the TG epigenetic actions of MXC will broaden our knowledge of how EDCs, in general, disrupt normal epigenetic programming in females, and facilitate the development of strategies to prevent and treat EDC-induced TG abnormalities.

描述（由申请人提供）：众所周知，在子宫内和/或新生儿发育期间接触环境压力源或有毒物质，例如内分泌干扰化学物质（EDC），可能会导致成人发病的疾病。这种有害的变化与异常的 DNA 甲基化模式以及其他表观遗传机制有关。令人高度关注的是，最近的研究表明，这种疾病易感性可以通过表观遗传机制传递给从未直接接触过 EDC 的后代。例如，在子宫内暴露于 EDC 后，睾丸异常通过雄性生殖细胞遗传给 F2-F4 代雄性。然而，这些影响被发现具有性别特异性，因为 F2-F3 雌性表现出较温和的表型，需要父母双方都接触 EDC。在本提案中，我们的目标是解决女性生殖系是否参与 EDC 暴露的跨代 (TG) 效应这一关键问题。甲氧滴滴涕 (MXC) 是一种 EDC，其作用类似于环境中许多其他 EDC，并被证明会引起性腺的表观遗传变化；因此，它将在本提案中用作 EDC 模型。我们的假设是，在发育的关键窗口期（此处定义为通过卵母细胞表观遗传重编程进行性腺分化的时期）暴露于 MXC，会导致卵巢中由卵母细胞表观遗传变化介导的 TG 效应。为了检验我们的假设，该提案有两个相互关联但又不同的具体目标：（1）确定 MXC 在暴露 F1 后 F3 代卵巢中的体细胞 TG 表观遗传效应。在E11和PND7之间，将用0、20 5g/kg/天MXC或50-100 mg/kg/天MXC治疗F1代近交雌性大鼠。这些雌性将与未经处理的雄性交配，并产生 F2-F4 雌性。最初，仅在 F3 雌性中评估卵巢形态、基因表达和生育力，因为观察 F3 代中的 TG 效应是建立 TG 效应的最低要求。将使用传统方法以及基于芯片的方法研究基因表达变化以及全局和基因特异性 DNA 甲基化变化。 (2) 研究 MXC 在 F1/F2 卵母细胞中诱导的表观遗传变化，这些变化可能导致 F3 中的 TG 效应。将分析印记基因和寄生 DNA 序列（例如卵母细胞中的反转录转座子）中的 DNA 甲基化模式，因为这些序列中的异常甲基化模式可能具有致病性。还将检查卵母细胞基因表达模式；基因表达变化和 DNA 甲基化之间的任何相关性都将得到阐明。拟议的研究将是第一个调查 EDCs 通过 F2 代以外的雌性生殖系传播的表观遗传 TG 效应的研究。我们认识到这项研究存在相当大的风险，但鉴于 EDC 在环境中广泛存在，对当代和后代的健康影响重大。对 MXC 的 TG 表观遗传作用的机制了解将拓宽我们对 EDC 一般如何破坏女性正常表观遗传编程的认识，并促进制定预防和治疗 EDC 诱导的 TG 异常的策略。