Microbiome Induced Epigenetic Changes in Intestinal Inflammation and Necrotizing Enterocolitis

项目总结 在早产儿中，过度的炎症反应与坏死性小肠结肠炎有关。 (NEC)，其机制尚不清楚。微生物区系及其代谢物，包括短链脂肪酸 可通过DNA甲基化和/或组蛋白去乙酰化以及特定的微生物组模式来修饰表观基因组 与脂代谢、肥胖和肥胖相关基因的DNA甲基化改变有关 发炎。 这项研究的长期目标是确定过度炎症反应的机制 导致NEC，并制定抗炎、治疗和预防策略。的具体假设 拟议的研究是由发育中的肠道微生物群引起的表观遗传变化导致 早产儿易患坏死性小肠结肠炎的过度免疫和炎症反应 刚出生的。我们打算通过首先在早产儿中建立DNA甲基化改变来检验这一假设。 NEC与匹配对照组的比较，在嵌套队列临床设计中的特定目的1.DNA甲基化 将在肠上皮细胞和外周血单核细胞中描绘模式，并确认 利用转录组学技术对粪便中肠上皮细胞的差异基因表达进行评估 全身和肠道炎症。在我们的第二个特定目标中，我们将测试特定的假设 微生物组和代谢组特征与表观基因组和转录组的变化有关 NEC早产儿。在入选的队列中，我们将通过元基因组学和 用于微生物代谢物的粪便和尿液代谢组，并记录临床元数据(例如，胎龄、 进料)进行多变量分析。我们预计会有不同的微生物组和代谢组特征 NEC的DNA甲基化改变。对手术样本中肠样的后续研究将用于 通过测量暴露于特定炎症后的表观遗传变化来机械地检验我们的假设， 从建议的研究中确定的微生物或代谢刺激。 拟议的研究是创新的，因为表观基因组的改变与微生物组和 早产儿的炎症还没有得到评估。我们提出了一种整体的、多组学的方法来 描述早产儿过度炎症的机制。我们的研究不仅将使 在新生儿领域的影响，其中主要器官发病率与炎症有关，但也在其他 在发病机制中，炎症是诱因和关键因素的患者和疾病。探索 微生物区系诱导的表观遗传学变化与炎症反应之间的关系可能支持 NEC的病理生理学，并导致新的早产儿预防策略。我们的研究是 意义重大，因为我们的工作将提供关于微生物组诱导的表观遗传变化的新知识 与癌症、感染和免疫等一系列疾病相关。

PROJECT SUMMARY In preterm neonates, excessive inflammatory responses have been implicated in necrotizing enterocolitis (NEC), the mechanisms for which are unclear. Microbiota and their metabolites including short chain fatty acids may modify the epigenome by DNA methylation and/or histone deacetylation, and specific microbiome patterns have been associated with altered DNA methylation of genes linked to lipid metabolism, obesity and inflammation. The long term goal of this research is to determine the mechanism for excessive inflammatory responses that lead to NEC and devise anti-inflammatory therapeutic and preventative strategies. The specific hypothesis of the proposed research is that epigenetic changes induced by the developing intestinal microbiome result in excessive immune and inflammatory responses that predispose to necrotizing enterocolitis in the preterm neonate. We intend to test this hypothesis by first establishing DNA methylation alterations in preterm infants with NEC compared to matched controls, in a nested cohort clinical design in Specific Aim 1. DNA methylation patterns will be delineated in intestinal epithelial cells and peripheral blood mononuclear cells and confirm differential gene expressions with transcriptomics in the intestinal epithelial cells from the stools and assess systemic and intestinal inflammation. In our second Specific Aim, we will test the hypothesis that specific microbiome and metabolomic signatures are associated with changes in the epigenome and transcriptome in preterm neonates with NEC. In the cohort enrolled, we will evaluate stool microbiome by metagenomics and stool and urine metabolome for microbial metabolites and record clinical metadata (e.g. gestational age, feeding) for multi-variable analysis. We anticipate distinct microbiome and metabolome signatures associated with DNA methylation alterations in NEC. Follow up studies of enteroids from surgical samples will be used to mechanistically test our hypothesis by measuring epigenetic changes after exposure to specific inflammatory, microbial or metabolomic stimuli that are identified from the proposed research. The proposed research is innovative as the epigenome alterations in relation to the microbiome and inflammation in the preterm infant have not been evaluated. We propose a holistic, multi-omics approach to delineate the mechanisms for excessive inflammation in the preterm infant. Our research will not only make an impact in the field of neonatology where major organ morbidity is related to inflammation but in also in other patients and diseases where inflammation is an inciting and key factor in the pathogenesis. Exploring the relationship between microbiota induced epigenetic changes and inflammatory responses may underpin the pathophysiology of NEC and lead to novel preventive strategies in the preterm neonate. Our research is significant because our work will provide new knowledge on microbiome-induced epigenetic changes that is relevant to a broad-spectrum of diseases such as cancer, infection and immunity.