FOLATE REQUIREMENTS OF PREGNANT HUMAN SUBJECTS

怀孕人类受试者的叶酸需求

• 批准号: 2202273
• 负责人: LYNN B BAILEY
• 金额: $ 14.24万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-09-01 至 1998-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2202273
• 关键词: affinity chromatography; blood chemistry; chemical kinetics; chemical synthesis; deuterium; dietary supplements; female; folate; gas chromatography mass spectrometry; high performance liquid chromatography; human pregnant subject; mother /embryo /fetus nutrition; nutrient bioavailability; nutrient requirement; nutrition related tag; pregnancy; urinalysis; vitamin metabolism

A chronic in vivo supplementation protocol with deuterium-labeled folic acid under controlled metabolic conditions will be used to estimate folate requirements of pregnant women. The primary research goal is to provide folate requirement estimates for pregnant women to be used for dietary intake recommendations and prenatal folic acid supplementation polices to ensure normal fetal development and maternal health. The specific objectives are to estimate folate requirements by (1) the application of kinetic methodology; and (2) quantitation of urinary folate excretory products. Deuterium labeled and unlabeled folic acid (D5, or D0) will be given throughout gestation beginning at 14 wks to 2 groups of pregnant women consuming controlled intakes of folate (400 or 800 micrograms/d). Requirement estimates will be compared to estimates determined in 2 nonpregnant control groups. The appearance and disappearance of the labeled folates and catabolites as determined by isotope enrichment of urine and blood will be the basis of the kinetic requirement- determination. The data will be fit to specific models and the requirement based on the estimation of total body pool and fractional catabolic rate. A second approach will be the quantitation of the sum of (1) urinary folate catabolites [D5, or D0 p-aminobenzyolglutamate (pABG) and derivatives (apABG, pABA); and (2) metabolized intact folate (CH3THFA). The contribution of catabolites present in the diet to urinary excretory products will be based on the recovery of D4 pABG added to the diet. Changes in kinetic parameters and quantitation of metabolized folate excretory products in response to the two levels of intake will serve as the basis for prenatal folate requirement estimates. These data will provide a justification for dietary folate and supplemental folic acid recommendation polices for pregnant women. Application of these new requirement data will ensure adequate intake of folate for prevention of health related consequences (i.e. neural tube defects, impaired fetal growth, megaloblastic anemia) of folate inadequacy in women of reproductive age.

氘标记叶酸的长期体内补充方案 在受控代谢条件下的叶酸将用于估计叶酸 孕妇的要求。 主要研究目标是提供 孕妇膳食叶酸需要量估计 摄入量建议和产前叶酸补充政策， 确保胎儿正常发育和母亲健康。 具体 目的是估计叶酸的需求量（1）应用 动力学方法;和（2）尿叶酸排泄的定量 产品. 氘标记和未标记的叶酸（D5或D 0）将在 在整个妊娠期间，从14周开始对2组妊娠 控制叶酸摄入量（400或800微克/天）的妇女。 需求估计将与2中确定的估计进行比较 非妊娠对照组。 的出现和消失。 通过同位素富集测定标记的叶酸和catenorase， 尿液和血液将是动力学要求的基础- 保持战略定力数据将适合特定的模型和要求 基于全身池和分解率的估计。 第二种方法将是定量（1）尿 叶酸分解代谢物[D5或D 0对氨基苄醇谷氨酸盐（pABG）和 衍生物（apABG，pABA）;和（2）代谢的完整叶酸（CH 3 THFA）。 饮食中存在的钙对尿排泄的贡献 产品将基于D4 pABG的回收添加到饮食中。 代谢叶酸的动力学参数变化和定量 排泄物对这两种摄入水平的反应将作为 产前叶酸需要量估计的基础。 这些数据将 提供膳食叶酸和补充叶酸的理由 对孕妇的建议政策。 应用该等新订 要求数据将确保摄入足够的叶酸，以预防 与健康相关的后果（即神经管缺陷、胎儿受损 生长，巨幼细胞性贫血）的妇女叶酸不足， 生育年龄