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怀孕期间(特别是在妊娠晚期)会受到影响，但还没有进行人类饮食研究来评估剂量-反应关系、母婴分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确定生物素的推荐膳食摄入量(RDA)。相反，估计成年人每天30微克生物素的适当摄入量(AI)水平，而不对孕妇进行向上调整。目的：本研究的目的是提供数据，为孕妇制定生物素RDA提供科学依据。本建议的具体目的是：i)检验孕期膳食生物素需求量增加的假设；ii)检验孕妇和胎儿生物素状态生物标志物呈正相关的假设；iii)调查膳食生物素摄入量与生物素状态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，在怀孕妇女(n=10，21-40岁，27周)和非怀孕对照妇女(n=10，21-40岁)中进行的为期12周的控制喂养研究将延长，以便能够在这些妇女中进行生物素的剂量反应评估。将对饮食中的生物素含量进行量化，同时测量母亲/胎儿生物素状况的生物标志物，包括与生物素缺乏(即3-羟基异戊酸)和生物素分解代谢(即双降生物素和生物素亚砜)有关的生物标志物。预期结果：这项研究将能够描述人类母亲和胎儿生物素状态之间的关系；洞察可能导致怀孕期间观察到的生物素状态不佳的因素；并有助于估计母亲饮食中生物素的摄入量，以满足怀孕期间不断增加的需求，并确保发育中的胎儿有足够的生物素供应。总而言之，这些数据有望为孕妇生物素RDA的开发提供科学信息，该生物素RDA旨在改善孕产妇和胎儿健康。 公共卫生相关性：拟议的人体研究将检查生物素状况指标对已知膳食生物素摄入量的反应，评估生物素在母体和胎儿体内的分布，并调查母体和胎儿生物素状况指标之间的关系。这项研究产生的数据有望为制定生物素推荐的孕妇膳食供给量提供科学依据，并指导怀孕期间是否需要补充生物素的决定。

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. PUBLIC HEALTH RELEVANCE: The proposed human study will examine the response of biotin status indicators to a known intake of dietary biotin, assess the distribution of biotin between maternal and fetal compartments, and investigate the relationship between maternal and fetal indicators of biotin status. The data generated from this study are expected to scientifically inform the development of a biotin recommended dietary allowance for pregnant women and guide decisions on the need for biotin supplementation during gestation.