Prenatal alcohol exposure disrupts maternal-fetal iron metabolism in FASD

描述（由申请人提供）：胎儿酒精谱系障碍（FASD）是神经发育障碍的主要原因。我们和其他人最近表明，怀孕期间最常见的微量营养素缺乏，母亲缺铁（ID），大大增加了后代对酒精损害的脆弱性，包括神经行为和神经解剖结果。本研究探讨了醇-铁相互作用的机制。具体来说，我们测试了产前乙醇暴露（PAE）阻碍铁从母亲到胎儿到胎儿大脑的流动的假设，通过乙醇的hepcidin失调。这种hepcidin失调阻碍了胎儿对铁的摄取，因此PAE恶化了胎儿的铁状态，尤其是在胎儿的大脑中。利用大鼠PAE模型，我们将记录PAE对胎儿和母体铁含量、关键铁依赖活性、蛋白质表达和活性以及控制铁摄取和利用的调节信号的影响。我们将进一步测试铁补充剂是否可以使胎儿脑铁含量和已知对铁-酒精相互作用敏感的脑活动正常化，使用临床上用于hepcidin失调的铁补充剂形式。我们的初步数据支持这一假设，并表明PAE显着破坏铁从母亲到胎儿到胎儿大脑的流动。我们发现在PAE下，胎儿肝脏保留铁以牺牲胎儿大脑为代价，即使母亲是铁充足的（is），胎儿大脑也会缺铁（ID）。如果母亲是ID，乙醇会恶化肝-脑的脱节，并阻止适应，否则会增强胎儿的铁摄取。因为铁对健康的大脑发育至关重要，乙醇对胎儿铁代谢的破坏可能解释了为什么乙醇会放大乙醇对神经发育的损害。关于PAE如何影响胎儿和母亲的营养利用，以及这些变化如何影响妊娠结局，我们知之甚少。考虑到临床干预已经在进行中，以测试包括铁在内的微量营养素补充剂是否会减少对FASD的易感性，了解PAE利用微量营养素的基本生物化学基础是至关重要的，因此，PAE如何改变营养需求。这项基础研究对于开发有效的、以证据为基础的饮食干预措施，减少胎儿对FASD的易感性至关重要。

DESCRIPTION (provided by applicant): Fetal Alcohol Spectrum Disorders (FASD) are a leading cause of neurodevelopmental disability. We and others recently showed that the most common micronutrient deficiency of pregnancy, maternal iron deficiency (ID), substantially heightens the offspring's vulnerability to alcohol's damage, including neurobehavioral and neuroanatomical outcomes. This proposal investigates the mechanism underlying this alcohol-iron interaction. Specifically, we test the hypothesis that prenatal ethanol exposure (PAE) impedes the flow of iron from mother to fetus to fetal brain, through ethanol's dysregulation of hepcidin. This hepcidin dysregulation impedes fetal iron uptake and thus PAE worsens fetal iron status and especially in fetal brain. Using a rat model of PAE, we will document PAE's impact upon fetal and maternal iron content, key iron-dependent activities, and the expression and activity of proteins and regulatory signals that control iron uptake and utilization. We will furthr test whether iron supplements can normalize fetal brain iron content and brain activities with known sensitivity to iron-alcohol interactions, using iron supplement forms that are used clinically for conditions where hepcidin is dysregulated. Our preliminary data support this hypothesis and show that PAE significantly disrupts iron flow from mother to fetus to fetal brain. We find that under PAE, fetal liver retains iron at the expense of fetal brain, and fetal brain becomes iron-deficient (ID) even though the mother is iron-sufficient (IS). If the mother is ID, ethanol worsens this liver-brain disconnect and prevents adaptations that would otherwise enhance fetal iron uptake. Because iron is essential for healthy brain development, ethanol's disruption of fetal iron metabolism may explain why ID magnifies ethanol's neurodevelopmental damage. Little is known about how PAE affects fetal and maternal nutrient utilization, and how such changes impact gestational outcome. Given that a clinical intervention is already underway to test if micronutrient supplements including iron will reduce vulnerability to FASD, it is essential to understand the basic biochemistry underlying micronutrient utilization by PAE and, thus, how PAE might change nutrient requirements. This fundamental research is crucial to develop effective, evidence-based dietary interventions that reduce fetal vulnerability to FASD.