E-Cigarette Vaping during Pregnancy and Lactation, Germ Cell Epigenetic Memory, and Transgenerational Asthma

围产期吸烟和非肠道尼古丁暴露与哮喘的高风险有关，而不仅仅是在 暴露的后代，但在从未接触过任何形式尼古丁的后代中也是如此，至少在 远至F3世代。孕妇对电子烟(e-cig)的使用一直在增加，这在很大程度上 这是因为人们认为蒸发是相对安全的。这种看法被怀疑是错误的，但很少有 目的评价电子烟对人体健康的不良影响。我们的调查将解决这些影响 电子烟暴露小鼠子代哮喘发病情况及蒸发中使用的调味品 怀孕了。我们还询问这种风险是否是跨代遗传的，以及遗传性可能是如何发生的。细菌 细胞是唯一从一代传到下一代的细胞，并且已经被证明是精致的 对环境的侮辱很敏感。基于这些考虑和我们的初步数据，我们假设 暴露在蒸发中会扰乱生殖细胞的表观遗传机制，导致表观遗传标记的改变。 导致一种可跨代遗传的哮喘表型。使用已建立的模型， 我们将在老鼠体内测试这一假设，方法是确定电子烟是否会增加后代患哮喘的风险：1) 对电子烟或尼古丁暴露天真的怀孕F0母亲和2)F1和F2母亲的子女。我们 将测试蒸发尼古丁(AIM 1A)和调味品(AIM 1B)是否对 跨代哮喘风险，这些风险是否相加，以及它们是否因过敏原而加剧 敏化(AIM 1C)。尼古丁诱导的哮喘与肺成纤维细胞的显著改变有关 表型，我们假设一旦表观基因组恢复到 很正常。因此，在AIM 2中，我们将评估尼古丁和电子烟调味品对生存能力的影响(AIM 2A)和 生殖细胞的表观遗传记忆(AIM 2B)使用多维组学工具(合并组学平台) 由我们的合作伙伴夏阳(UCLA)开发，我们将分析在不同的分子路径上产生的数据 数据集，以确定生殖细胞表观遗传学如何受到带有或不带有调味品的电子烟的影响(AIM 2C)。 最后，在AIM 2D中提出的研究将试图逆转从F3分离的成纤维细胞的表观遗传学变化 使用RNAi的电子烟产生的后代。因变量将包括分子表型的表达 哮喘表型的标志物和分离的成纤维细胞的功能特征 来自F3代，与适当的对照进行比较。我们预计Aim 2中的研究将显示出可重复性 从生殖细胞分化为肺成纤维细胞的小鼠的表型变化： 1)直接接触电子烟；或2)从未以任何形式接触过尼古丁，但继承了 祖传接触电子烟。这些研究将重要地推进我们对蒸发如何的机械知识 可能会导致子代持续的、跨代遗传的哮喘风险。此外，我们的研究将有助于 告知有关接触电子烟尼古丁和电子烟调味品的监管政策。

Perinatal exposure to smoking and parenteral nicotine has been linked to a high risk of asthma, not just in the exposed offspring, but also transgenerationally in progeny who never encounter any form of nicotine at least as far as the F3 generation. Use of electronic-cigarettes (e-cigs) by pregnant women has been increasing, largely the result of the perception that vaping is relatively safe. This perception is suspected to be erroneous, but few objective studies have evaluated the adverse health effects of vaping. Our investigation will address the effects of vaping and flavorings used in vaping on development of asthma in progeny of mice exposed to e-cigs during pregnancy. We also ask whether this risk is transgenerationally inherited, and how heritability might occur. Germ cells are the only cells that are passed from one generation to the next, and have been shown to be exquisitely sensitive to environmental insults. Based on these considerations and on our preliminary data, we hypothesize that exposure to vaping disrupts the epigenetic machinery in germ cells, causing alterations of epigenetic marks across the genome that leads to a transgenerationally heritable asthma phenotype. Using established models, we will test this hypothesis in vivo in mice by determining whether e-cigs increase risk of asthma in: 1) offspring of pregnant F0 mothers and 2) offspring of F1 and F2 mothers who were naïve to e-cig or nicotine exposure. We will test whether vaporized nicotine (AIM 1A) and flavorings (AIM 1B) have independent effects on transgenerational asthma risk, whether these risks are additive and whether they are exacerbated on allergen sensitization (AIM 1C). Nicotine-induced asthma is associated with a marked alteration of lung fibroblast phenotype, and we hypothesize that these alterations are reversible once the epigenome is restored towards normal. Hence, in AIM 2, we will assess the effects of nicotine and e-cig flavorings on viability (AIM 2A) and epigenetic memory (AIM 2B) of germ cells. Using multi-dimensional -omics tools (the Mergeomics platform) developed by our Co-I Xia Yang (UCLA), we will analyze data generated on molecular pathways across different data sets to determine how germ cell epigenetics are impacted by e-cigs with or without flavorings (AIM 2C). Finally, studies proposed in AIM 2D will attempt to reverse epigenetic changes in fibroblasts isolated from F3 progeny produced by e-cigs using RNAi. Dependent variables will include expression of molecular phenotypic markers that are the hallmarks of the asthmatic phenotype, and functional characteristics of fibroblasts isolated from F3 progeny, compared with appropriate controls. We anticipate that studies in Aim 2 will show reproducible alteration of the phenotype of lung fibroblasts that have differentiated from germ cells in mice that have either: 1) been directly exposed to e-cigs; or 2) never been exposed to nicotine in any form, but inherited the effects of ancestral exposure to e-cigs. These studies will importantly advance our mechanistic knowledge of how vaping might lead to persistent, transgenerationally-inherited risk of asthma in offspring. Further, our studies will help inform regulatory policies concerning exposure to e-cig nicotine and flavorings from vaping.