The epigenetic impact of in utero opioid exposure on Generation Z

项目摘要 在怀孕期间用于缓解疼痛的阿片类药物的惊人增长导致了越来越多的 新生儿重症监护病房（NICU）新生儿药物戒断的入院人数，也称为 新生儿戒断综合征（NAS）。有证据表明，这些NAS婴儿更有可能成为 近年来，在晚年生活中出现了“上瘾”。虽然确切的机制还没有 确定，有强有力的证据表明，DNA甲基化在服用慢性阿片类药物的个体中发生了改变， OPRM 1启动子的多态性和DNA甲基化最近被证明会影响 NAS成果。我们的假设是，在子宫内阿片类药物暴露导致表观遗传过程， 对胎儿/儿童的潜在长期临床后果，例如增加对 “阿片类药物（滥用）使用障碍”。拟议试点项目的理由是， 宫内暴露于阿片类药物的新生儿的DNA甲基化将为研究其关系奠定基础 DNA甲基化和其他表观遗传过程与儿童期特定疼痛行为之间的关系 以及日后的毒瘾在这项初步探索性纵向病例对照研究中，我们将评估 母体在妊娠期间使用阿片类药物对缓解疼痛影响及其导致的子宫内阿片类药物延长 病例组（20名服用处方阿片类药物缓解疼痛的母亲及其新生儿）和对照组（20名 未暴露的母亲/婴儿）。将使用液相色谱法定量母体阿片类药物暴露- 分娩时（毛发）和新生儿慢性暴露的串联质谱分析将在 出生时采集胎粪和毛发样本，2个月时再次采集（毛发）。我们提出三个具体目标：（1） 比较暴露组和对照组的新生儿结局（NAS结局，特别是免疫期间的疼痛）， 与未暴露的婴儿相比，（2）评估新生儿DNA甲基化模式（OPRM 1和COMT启动子， LINE-1）和（3）评价阿片代谢和遗传预测因子（CYP 2D 6/3A 4， OPRM 1和COMT）的新生儿结局和NAS管理。这种方法是创新的， 新生儿重复DNA甲基化检测评估宫内后的行为和疼痛表型 阿片类药物暴露尚未进行，并可能（a）提供关键的洞察力， 阿片耐受性和药物添加的潜在机制/途径，（B）帮助提出策略， 提高我们诊断和治疗阿片类药物成瘾能力，以及（c）预防个人接触阿片类药物 被确定为由于遗传/表观遗传因素而有阿片类药物依赖、耐受和成瘾的风险 标记。 公共卫生声明 这项拟议中的研究非常及时，因为用于缓解疼痛的阿片类药物导致的死亡 在美国成为一种流行病，每天造成50人死亡，FDA最近的安全公告 关于怀孕期间使用止痛药的风险，强调了目前的“过度”， 阐明子宫内阿片类药物暴露的长期影响是关键， 进一步了解遗传和表观遗传对阿片类药物成瘾的贡献， 预测和预防阿片类药物滥用和慢性疼痛。

Project Summary An alarming rise in opioids prescribed for pain relief during pregnancy has resulted in an increasing number of neonatal intensive care unit (NICU) admissions for neonatal drug withdrawal, also called neonatal abstinence syndrome (NAS). Evidence that these NAS babies are more likely to become ‘addicted’ later in life has emerged in recent years. Although the exact mechanism has not been identified, there is robust evidence that DNA methylation is altered in individuals taking chronic opioids, and polymorphisms and DNA methylation of OPRM1 promoter have recently been shown to influence NAS outcomes. Our hypothesis is that in utero opioid exposure results in epigenetic processes with potentially long term clinical consequences for the fetus/child such as an increased vulnerability to develop an ‘opioid (mis)use disorder’. The rationale for the proposed pilot project is that evaluation of DNA methylation in neonates exposed in utero to opioids will lay the foundation to study the relationship between DNA methylation and other epigenetic processes with specific pain behaviors during childhood and drug addiction later in life. In this pilot exploratory longitudinal case-control study we will evaluate the impact of maternal opioid use for pain relief during pregnancy and consequent prolonged in utero opioid exposure in cases (20 mothers on prescribed opioids for pain relief and their neonate) and controls (20 unexposed mothers/babies). Maternal opioid exposure will be quantified using Liquid Chromatography– Tandem Mass Spectrometry at delivery (hair), and neonatal chronic exposure will be evaluated on meconium and hair samples at birth, and again at 2 months (hair). We propose 3 specific aims: (1) compare neonatal outcomes (NAS outcomes & pain during immunization in particular) between exposed vs unexposed babies, (2) assess neonatal DNA methylation patterns (OPRM1 & COMT promoters, LINE-1) at birth and 2 months and (3) evaluate opioid metabolism and genetic predictors (CYP2D6/3A4, OPRM1 & COMT) of neonatal outcomes and NAS management. Such an approach is innovative as repeated DNA methylation assays in neonates evaluating behavioral and pain phenotypes after in utero opioid exposure have not been undertaken and may (a) provide key insight into the mechanisms/pathways underlying opioid tolerance and drug addition, (b) help propose strategies to improve our ability to diagnose and treat opioid addiction and (c) prevent opioid exposure in individuals identified as being at risk for opioid dependence, tolerance and addiction due to genetic/epigenetic markers. Public Health Statement The proposed research is extremely timely because death from opioids prescribed for pain relief has become an epidemic in the U.S. causing 50 deaths every day and FDA’s recent safety announcement regarding risks associated with pain medicines use during pregnancy emphasizes the current ‘over- exposure’ to opioids in the U.S. Elucidating the long-term effects of in utero opioid exposure is key to further our understanding of the genetic and epigenetic contributions to opioid addiction, and potentially predict and prevent opioid misuse and chronic pain.