Biotin Status During Pregnancy

描述（由申请人提供）：虽然人们认识到生物素在人类妊娠期间（特别是在妊娠晚期）会受到损害，但尚未进行人类饮食研究来评估剂量-反应关系、母胎区隔或饮食生物素需求。因此，医学研究所的食品和营养委员会无法建立生物素的推荐膳食津贴（RDA）。相反，估计成人每天摄入30微克生物素的适当水平（AI）没有对孕妇进行向上调整。目的：本研究的目的是提供数据，为孕妇生物素RDA的制定提供科学依据。具体目的：本提案的具体目的是：i)验证怀孕期间饮食生物素需求增加的假设；Ii)检验母体和胎儿生物素状态的生物标志物正相关的假设；iii)研究膳食生物素摄入量与生物素状态的有效生物标志物之间的剂量-反应关系。程序：为了实现这些目标，在孕妇（n=10, 21-40, 27周）和非妊娠对照妇女（n=10, 21-40）中进行的为期12周的对照喂养研究将延长，以便对这些妇女进行生物素的剂量反应评估。将对饲料中的生物素含量进行定量，同时测量母体/胎儿生物素状态的生物标志物，包括与生物素缺乏（即3-羟基异戊酸）和生物素分解代谢（即双去甲生物素和生物素亚砜）相关的生物素状态。预期结果：本研究将能够描述人类母体和胎儿生物素状态之间的关系；提供对可能导致妊娠期间观察到的亚理想生物素状态的因素的见解；并有助于估计孕妇膳食生物素摄入量的水平，以满足怀孕期间增加的需求，并确保向发育中的胎儿提供足够的生物素。总的来说，这些数据有望科学地为孕妇生物素RDA的开发提供信息，旨在改善孕产妇和胎儿的健康。

DESCRIPTION (provided by applicant): Although it is recognized that biotin status is compromised during human pregnancy (particularly during the third trimester), no human dietary studies have been conducted to assess dose-response relationships, maternal-fetal compartmentation, or dietary biotin requirements. Consequently, the Food and Nutrition Board of the Institute of Medicine were not able to establish a recommended dietary allowance (RDA) for biotin. Instead an adequate intake (AI) level of 30 mcg biotin per day for adults was estimated without upward adjustments for pregnant women. Goal: The goal of this study is to provide data that will scientifically inform the development of a biotin RDA for pregnant women Specific Aims: The specific aims of this proposal are to: i) test the hypothesis that dietary biotin requirements are increased during pregnancy; ii) test the hypothesis that maternal and fetal biomarkers of biotin status are positively correlated; and iii) investigate the dose-response relationship between dietary biotin intake and validated biomarkers of biotin status. Procedure: To accomplish these aims, a 12-week controlled feeding study conducted in pregnant women (n=10, 21-40y, 27 wk) and nonpregnant control women (n=10, 21-40 y) will be extended to enable a dose response assessment of biotin in these women. Quantitation of the biotin content of the diet will be performed along with measurements of maternal/fetal biomarkers of biotin status including those linked to biotin deficiency (i.e. 3-hydroxyisovaleric acid) and biotin catabolism (i.e. bisnorbiotin and biotin sulfoxide). Expected Outcomes: This study will be able to delineate the relationship between maternal and fetal biotin status in humans; provide insight into the factors that may contribute to the suboptimal biotin status observed during pregnancy; and facilitate an estimation of the level of maternal dietary biotin intake required to meet the increased demands during pregnancy and ensure an adequate supply of biotin to the developing fetus. Collectively, these data are expected to scientifically inform the development of a biotin RDA for pregnant women that is designed to improve maternal and fetal health.