Impact of chronic alcohol consumption on the functional and epigenetic landscapes of monocytes and their progenitors

长期饮酒对单核细胞及其祖细胞功能和表观遗传景观的影响

• 批准号: 10502298
• 负责人: Ilhem Messaoudi
• 金额: $ 35.17万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-11-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10502298
• 关键词: Impact; chronic; alcohol; consumption; functional

PROJECT SUMMARY Approximately ~7% of alcohol-consuming individuals engage in chronic heavy drinking (CHD), which is associated with increased susceptibility to infections as well as impaired wound healing and tissue repair resulting in poor post-operative outcomes. Evidence suggests that many of these defects are mediated by excessive inflammatory responses originating from myeloid cells, notably circulating monocytes and tissue- resident macrophages. These data were primarily generated from in vitro studies where monocytes from healthy donors or cell lines are treated high doses of ethanol. However, the mechanisms underlying the effects of CHD cannot be fully understood by in vitro studies because immune cells carry out their functions in a multicellular environment in which alcohol has widespread effects. Due to a lack of studies utilizing reliable in vivo models, our understanding of the mechanisms underlying aberrant inflammatory responses in the context of CHD remains incomplete. To address these knowledge gaps, we propose to leverage a rhesus macaque model of voluntary ethanol self-administration that accurately mirrors human physiology and recapitulates complex human drinking behavior. Using this model, our lab has recently demonstrated that CHD results in transcriptional and epigenetic rewiring of circulating monocytes and splenic macrophages, resulting in aberrant responses to LPS stimulation. However, the functional implications of this reprogramming and the epigenetic mechanisms controlling it remain unknown. Importantly, because monocytes are short-lived circulating cells under constant repopulation from the bone marrow, these observations suggest perturbations of the hematopoietic niche. Preliminary single-cell analyses of hematopoietic progenitors point to a shift in differentiation potential towards more mature myeloid progenitors with alcohol. However, a link between this observation in progenitor cells and their differentiated states in blood and tissue remains unclear. In this application, we propose to test the hypothesis that chronic alcohol consumption reprograms the epigenetic landscape of monocyte progenitors in the bone marrow giving rise to circulating monocytes poised towards a hyper- inflammatory response. We will first examine the impact of CHD on functional reprogramming of circulating monocytes, implementing assays to test their ability to migrate, phagocytose, and generate proper metabolic responses. We will next examine the effect of stimulation on the monocyte epigenetic landscape through assessment of chromatin accessibility and abundance of specific histone modifications. Finally, we will determine the effect of CHD on the differentiation potential, transcriptome activation, and epigenetic rewiring of bone marrow myeloid progenitors and integrate these data with those obtained from peripheral blood monocytes. Completion of this proposal will provide novel insight into the impact of CHD on myelopoiesis and mechanisms by which it compromised immunity and host defense as well as design interventions to mitigate these adverse events and improve immunological outcomes.

项目概要 大约 7% 的饮酒者患有慢性大量饮酒 (CHD)，这是 与感染易感性增加以及伤口愈合和组织修复受损有关 导致术后效果不佳。有证据表明，许多这些缺陷是由 源自骨髓细胞，特别是循环单核细胞和组织的过度炎症反应 常驻巨噬细胞。这些数据主要来自体外研究，其中来自健康的单核细胞 供体或细胞系接受高剂量的乙醇处理。然而，CHD 影响的机制 体外研究无法完全理解，因为免疫细胞在多细胞中发挥其功能 酒精具有广泛影响的环境。由于缺乏利用可靠的体内模型的研究， 我们对先心病背景下异常炎症反应机制的理解 仍然不完整。为了解决这些知识差距，我们建议利用恒河猴模型 自愿的乙醇自我管理，准确反映人类生理学并概括复杂的人类 饮酒行为。使用这个模型，我们的实验室最近证明了 CHD 会导致转录和 循环单核细胞和脾巨噬细胞的表观遗传重新布线，导致对 LPS 的异常反应 刺激。然而，这种重编程和表观遗传机制的功能意义 控制它仍然未知。重要的是，因为单核细胞是在恒定条件下寿命较短的循环细胞 从骨髓中重新增殖，这些观察结果表明造血生态位受到干扰。 造血祖细胞的初步单细胞分析表明分化潜力向 与酒精相比，骨髓祖细胞更加成熟。然而，祖细胞中的这一观察结果与 它们在血液和组织中的分化状态仍不清楚。在此应用中，我们建议测试 假设长期饮酒会重新编程单核细胞的表观遗传景观 骨髓中的祖细胞产生循环单核细胞，准备过度 炎症反应。我们将首先检查冠心病对循环系统功能重编程的影响 单核细胞，进行检测以测试其迁移、吞噬和产生适当代谢的能力 回应。接下来我们将通过以下方式检查刺激对单核细胞表观遗传景观的影响： 评估染色质可及性和特定组蛋白修饰的丰度。最后，我们将确定 CHD 对骨分化潜能、转录组激活和表观遗传重连的影响 骨髓祖细胞并将这些数据与从外周血单核细胞获得的数据整合。 该提案的完成将为先天性心脏病对骨髓细胞生成的影响和机制提供新的见解 它损害了免疫力和宿主防御，并设计干预措施来减轻这些不利的影响 事件并改善免疫结果。