Identifying DNA Methylation Alterations of Chronic Effects Of Blast and Disturbed Sleep

摘要 创伤性脑损伤是军队死亡和疾病的一个重要原因，据估计 返回的伊拉克自由行动/持久自由行动(阿富汗)退伍军人中有10%-20% 遭受了脑外伤，许多人的症状表明轻度脑损伤(MTBI)的残余效应无法识别 在出院前。为了认识到反复暴露在爆炸中的潜在后遗症，其中之一可能是 MTBI，2020年国防授权法案包括一项强制记录爆炸暴露的条款 在训练和战斗期间，为未来的风险缓解提供信息。拟议研究的重点是调查 在操作训练期间暴露于冲击波和相关症状的影响。与国防部合作 沃尔特里德陆军研究所(WRAIR)的调查人员，我们已经获得了大量匿名的临界值 来自作战爆炸训练课程的军事和执法人员的血液样本，这将使 美国将进行系统的DNA甲基化和转录研究。我们有2387个生物样本样本 以及来自突破和大口径步枪协议的人口统计、症状和爆炸传感器数据 反映了退伍军人因其特定的军事职业专长(MOS)而暴露的风险 有反复的职业超压暴露(ROPE)，导致对mTBI和 相关症状。这项研究的首要目标是将转录调控扰动与 随着冲击波的累积暴露，慢性生理和心理症状并存。融合 该领域的证据和我们自己的研究已经揭示了与绳索相关的分子微扰。 具体地说，我们已经显示了BLAST相关的DNA甲基化(一种高度稳定的表观遗传标记)在 涉及睡眠和昼夜节律功能的基因，激发了我们对睡眠障碍的深入表型 在拟议的研究中，退伍军人手持绳索。在这里，我们将追求以下目标：1)鉴定DNA甲基化 持续队列中与累积职业接触冲击波相关的扰动；2)识别DNA 用绳索跟踪的甲基化模式以及相关的生理和心理症状 队列；以及3)确定与患有MOS的退伍军人的累积BLAST相关的DNA甲基化模式的改变 暴露在新招募的职业性冲击波中。DNA甲基化与基因座转录模式 在前两个目标中确定的将在招募的退伍军人中进行调查，涉及不同的持续时间和 职业暴露谱以确定这些基因座是否也与累积 BLAST和相关临床症状，包括睡眠障碍，合并mTBI、创伤后应激障碍和/或重大 这些退伍军人中的抑郁障碍这将使我们能够通过以下途径将爆炸诱导的分子变化联系起来 DNA甲基化改变在遭受BLAST慢性影响的退伍军人中长期存在。 这项研究将导致发现DNA甲基化风险标记，可能有助于识别处于风险中的退伍军人 在绳索虚弱的症状出现之前，潜在地允许我们进行临床干预。

SUMMARY Traumatic brain injury (TBI) is a significant cause of death and disease in the armed forces, and it has been estimated that 10-20% of returning Operation Iraqi Freedom/Operation Enduring Freedom (Afghanistan) Veterans have suffered a TBI, with many having symptoms suggestive of the residual effects of mild TBIs (mTBIs) not recognized prior to discharge. In recognition of the latent residual effects of repeated exposures to blast, one of which may be mTBI, The 2020 National Defense Authorization Act includes a provision mandating documentation of blast exposure during both training and combat to inform future risk mitigation. The focus of the proposed study is to investigate the effects of exposures to blast and related symptomology incurred during operational training. In collaboration with DoD Walter Reed Army Institute of Research (WRAIR) investigators, we have obtained a critical mass of anonymized blood samples from military and law enforcement personnel from operational blast training courses, which will allow us to perform systematic DNA methylation and transcriptional studies. We have 2387 biological sample specimens along with demographic, symptom, and blast sensor data from both breaching and large caliber rifle protocols reflecting the exposures incurred by Veterans who because of their specific military occupational specialty (MOS) have repeated occupational overpressure exposure (ROPE), resulting in increased susceptibility to mTBI and associated symptoms. The overarching goal of this study is to link transcriptional regulatory perturbations associated with cumulative exposure to blast to chronic co-occurring physiological and psychological symptoms. Converging evidence in the field and from our own research has revealed molecular perturbations associated with ROPE. Specifically, we have shown blast associated alterations in DNA methylation (a highly stable epigenetic mark) in genes involved in sleep and circadian functioning, motivating our in-depth phenotyping of sleep disturbance in Veterans with ROPE in the proposed study. Here we will pursue the following aims: 1) Identify DNA methylation perturbations associated with cumulative occupational exposure to blast in ongoing cohorts; 2) Identify DNA methylation patterns that track with ROPE and associated physiological and psychological symptoms in ongoing cohorts; and 3) Identify altered DNA methylation patterns associated with cumulative blast in Veterans with MOS exposed to occupational blast newly recruited for this study. DNA methylation and transcriptional patterns in loci identified in the first 2 aims will be investigated in Veterans recruited with MOS involving varying durations and spectrum of exposures to occupational blast to determine whether these loci are also associated with cumulative blast and related clinical symptoms including sleep disturbance, with comorbid mTBI, PTSD and/or Major Depressive Disorder in these Veterans This will allow us to causally link blast-induced molecular changes via DNA methylation alterations that persist long-term in our Veterans who suffer from the chronic effects of blast. This study will lead to discovery of DNA methylation risk markers that may aid in identification of Veterans at risk before debilitating symptoms of ROPE can emerge, potentially allowing us to intervene clinically.