MicroRNAs as Biomarkers of Exposure and Effect in Fetal Alcohol Spectrum Disorders

 描述(由申请人提供)：胎儿酒精谱系障碍(FASD)的诊断在婴儿期和许多受影响的非综合征儿童中是困难的，他们没有面部圣痕。前景看好的胎粪和血液代谢生物标记物已经开发出来。然而，这些暴露的标志物只能适度地预测不良反应，而且是在生物底物中测量的，只有在有限的发育窗口中才能获得。我们将评估循环血浆microRNAs(CirmiRNAs)的生物标志物潜力，CirmiRNAs是一种分泌到血流中的非蛋白质编码的小RNA，可以在不同的出生年龄获得，并可能作为内分泌因子。Pi Miranda及其同事发现，在子宫内，母体酒精暴露会导致新生绵羊CirmiRNAs的表达模式发生变化，包括先前发现的对乙醇敏感的miRNA miR-9，其消融导致斑马鱼的表型与产前酒精暴露中看到的类似。基于这些临床前数据，我们假设产前酒精暴露导致人类CirmiRNAs表达模式的改变，这可能是暴露的生物标志物，并且产前酒精暴露改变的特定CirmiRNAs也将作为胎儿酒精相关神经发育和/或生长缺陷的生物标志物。为了验证这一假设，我们建议在南非开普敦的开普敦有色人种(混合血统)人口中筛选一组独特的酒精暴露婴儿中的CirmiRNA生物标记物，开普敦是全球胎儿酒精综合征发病率最高的地区之一。皮雅各布森及其同事目前正在对这一人群中的婴儿进行一项研究，其中包括怀孕期间预期获得的详细的母亲饮酒访谈、专家畸形专家的FASD诊断、新生儿结构磁共振数据、身体生长测量以及在6.5个月和12个月的认知评估。产后。在2wk时，将从该队列中获得30-35名重度暴露婴儿和30-35名对照婴儿的血浆样本，用于miRNA分析。6.5mo。产后。使用实时聚合酶链式反应阵列，我们将尝试识别区分酒精暴露婴儿和对照组的CirmiRNAs谱。然后，我们将确定因酒精暴露而改变的CirmiRNAs是否可以预测胎儿与酒精相关的发育结果，包括出生尺寸较小、大脑结构异常、认知功能较差以及FASD诊断。这项建议解决了开发诊断生物标记物的迫切需要，既可以用于产前酒精暴露，也可以用于在新生儿期内和之后获取的样本的影响。它对PA-13-197“细胞外RNA在调节酒精对健康的影响中的作用”做出反应，其具体重点是生物标记物的开发。FASD中独特的CirmiRNAs图谱的证据有可能揭示新的内分泌机制，调节胎儿酒精暴露的影响，这可能为开发新的治疗方法提供基础。

 DESCRIPTION (provided by applicant): Diagnosis of fetal alcohol spectrum disorders (FASD) is difficult in infancy and in the many affected nonsyndromal children, who do not manifest facial stigmata. Promising meconium- and blood-based metabolic biomarkers have been developed. However, these markers of exposure are only moderately predictive of adverse effects and are measured in biological substrates that can be obtained only during limited developmental windows. We will assess the biomarker potential of circulating plasma microRNAs (cirmiRNAs), small non-protein-coding RNAs that are secreted into the blood stream, can be acquired at different postnatal ages, and may serve as endocrine factors. PI Miranda and colleagues have found that in utero maternal alcohol exposure leads to an altered expression pattern of cirmiRNAs in newborn sheep, including a previously identified ethanol-sensitive miRNA, miR-9, the ablation of which leads to a zebra fish phenotype similar to that seen in prenatal alcohol exposure. Based on these pre-clinical data, we hypothesize that prenatal alcohol exposure leads to an altered expression pattern of cirmiRNAs in humans that may serve as a biomarker for exposure and that specific cirmiRNAs altered by prenatal alcohol exposure will also serve as biomarkers for fetal alcohol-related deficits in neurodevelopment and/or growth. To test this hypothesis, we propose to screen for cirmiRNA biomarkers in a unique cohort of alcohol-exposed infants from the Cape Colored (mixed ancestry) population in Cape Town, South Africa, which has among the highest worldwide incidence of fetal alcohol syndrome. PI Jacobson and colleagues are currently conducting a study of infants from this population, which includes detailed maternal alcohol consumption interviews obtained prospectively during pregnancy, FASD diagnosis by expert dysmorphologists, neonatal structural MRI data, physical growth measurements, and cognitive assessments at 6.5 and 12 mo. postpartum. Plasma samples will be obtained for miRNA profiling from 30-35 heavily exposed and 30-35 control infants from this cohort at 2 wk. and 6.5 mo. postpartum. Using real-time PCR arrays, we will attempt to identify a profile of cirmiRNAs that distinguish alcohol-exposed infants from controls. We will then determine whether the cirmiRNAs that are altered by alcohol exposure predict fetal alcohol-related developmental outcomes, including smaller birth size, structural brain anomalies, poorer cognitive function, and FASD diagnosis. This proposal addresses a critical need for developing diagnostic biomarkers for both prenatal alcohol exposure and effect from samples acquired during and beyond the neonatal period. It is responsive to PA-13-197, "The Role of Extracellular RNA in Mediating the Health Effects of Alcohol," with its specific focus on biomarker development. Evidence of distinctive cirmiRNAs profiles in FASD has potential to uncover novel endocrine mechanisms mediating effects of fetal alcohol exposure that may provide the basis for development of novel therapies.