FOLATE STATUS IN INTRAUTERINE GROWTH RETARDED INFANTS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 叶酸缺乏在IUGR中的作用尚不确定。本研究将为叶酸、叶酸辅助因子和叶酸调节酶在胎儿宫内发育受限新生儿中的作用提供初步证据。据推测，与正常发育的新生儿相比，IUGR新生儿将出现叶酸和维生素B12代谢异常。将采集30名IUGR新生儿和90名对照组新生儿的脐带血。分娩后，5-15毫升的脐带血将被收集在预先冷冻的EDTA试管中(5-15毫升)，分离，带到(体积/重量)1%抗坏血酸中，快速冷冻并在-20℃下储存，直到分析叶酸辅助因子。5毫升将被放置在预先冷冻的红色顶部，允许凝块和血清分离，等分到750 L等分，快速冷冻并储存在-20℃直到代谢物分析。我们将使用我们实验室开发的新的和灵敏的分析方法来证实在胎儿宫内发育迟缓模型中所观察到的结果。代谢物测定：血清蛋氨酸、SAM和SAH将通过Sabler博士实验室的稳定同位素稀释法进行测定。此外，该方法还会得出有助于区分叶酸和维生素B12缺乏的其他叶酸和维生素B12代谢物的浓度：二甲甘氨酸、甲基甘氨酸、同型半胱氨酸、丝氨酸、甘氨酸、半胱氨酸、甲基丙二酸、色氨酸和半胱氨酸。叶酸辅酶测定：血浆中总叶酸、5-甲基-四氢呋喃、5，10-亚甲基四氢呋喃和四氢呋喃的甲酰基(5-甲酰-四氢呋喃、10-甲酰-四氢呋喃、5，10-亚甲基-四氢呋喃)将通过直接探针MS检测，这是我们在Kolhouse博士的实验室12开发的技术。我们假设与对照组相比，IUGR婴儿将有叶酸缺乏的证据。我们预计我们将生成叶酸和代谢物值的标准数据，并使用这些新的更灵敏的分析方法直接确定叶酸缺乏和IUGR之间的潜在联系。代谢物分析已经在动物和人体试验中得到了验证，并且具有很好的重复性。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The role of folate deficiency in IUGR is uncertain. This study will provide preliminary evidence for the roles of folate, folate cofactors and the enzymes of folate regulation in human intrauterine growth restricted neonates. It is hypothesized that IUGR newborns will have abnormalities of folate and vitamin B12 metabolism compared to appropriately grown newborns. Cord blood will be collected on 30 IUGR newborns and 90 control newborns. After delivery, 5-15 cc of cord blood will be collected in prechilled EDTA tubes (5-15 cc) separated, brought to (vol/wt) 1% ascorbic acid, snap frozen and stored at -20 C until analysis for folate cofactors. 5 cc will be placed in a prechilled red top, allowed to clot and serum separated, aliquoted to 750 l aliquots, snap frozen and stored at -20 C until analysis for metabolites.We will use novel and sensitive assays developed in our laboratories to confirm observations made in a fetal sheep model of IUGR. Metabolite assay: Serum methionine, SAM and SAH will be determined by the stable isotope dilution method in the laboratory of Dr. Stabler 13. In addition, this method yields the concentrations for other metabolites of folate and vitamin B12 that aid in distinguishing folate from vitamin B12 deficiency: dimethylglycine, methylglycine, homocysteine, serine, glycine, cysteine, methyl- malonic acid, tryptophan, and cystathionine. Folate coenzyme assay: Plasma will be assayed for total folate, 5-methyl-THF, 5,10 methylene THF and the formyl groups of THF (5-formyl-THF, 10-formyl-THF, 5,10 methenyl-THF) by direct probe MS using a technique that we have developed in Dr. Kolhouse's laboratory 12. We hypothesize that IUGR infants will have evidence for folate deficiency compared to controls. We anticipate that we will generate normative data for folate and metabolite values and using these new more sensitive assays directly determine the potential association between folate deficiency and IUGR. The metabolite assays have been validated in animal and human testing and are very reproducible.