METABOLISM OF NON ESSENTIAL AMINO ACIDS IN HUMAN PREGNANCY

人类怀孕期间非必需氨基酸的代谢

• 批准号: 6115249
• 负责人: SATISH C KALHAN
• 金额: $ 1.92万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-12-01 至 1999-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6115249
• 关键词: aminoacid metabolism; chemical kinetics; clinical research; diet therapy; embryo /fetus; female; gestational age; glycine; human pregnant subject; human subject; insulin dependent diabetes mellitus; mother /embryo /fetus nutrition; nitrogen metabolism; nutrition related tag; pregnancy; prenatal growth disorder; serine; urea; women's health

The proposed study will quantify the kinetics and metabolism of serine during human pregnancy and examine its possible relation to fetal growth by examining such populations with fetal macrosomia and intrauterine growth retardation. It is hypothesized that as gestation advances and as the rates of urea synthesis decline, a significant change in the intrahepatic nitrogen metabolism occurs wherein increased amounts of nitrogen from ureagenic precursors are transferred to synthesize non-essential amino acids such as serine and glycine, and that glucose is a major source of serine carbon. It is further hypothesized that significant amounts of serine and glycine may be transferred to the fetus. Diabetes in pregnancy is characterized by increased protein breakdown, and thus it is expected that there is an increased rate of serine and glycine turnover. The plan of investigation continues to be to study normal pregnant women, pregnant women with insulin dependent diabetes, pregnant women with IUGR fetuses, women undergoing scheduled cesarean sections and non-pregnant controls. The normal pregnant women will be studied serially through pregnancy. Preliminary data suggest a pregnancy related decrease in serine turnover. During glucose infusion there was a consistent decrease in serine turnover. The significance of these changes in serine kinetics needs further evaluation.

这项拟议的研究将量化人类怀孕期间丝氨酸的动力学和代谢，并通过检测患有巨大儿和宫内生长迟缓的人群来研究其与胎儿生长的可能关系。假设随着妊娠的进展和尿素合成速率的下降，肝脏内的氮代谢发生了显著的变化，其中来自尿素合成前体的大量氮被转移到合成丝氨酸和甘氨酸等非必需氨基酸，而葡萄糖是丝氨酸碳的主要来源。进一步的假设是，大量的丝氨酸和甘氨酸可能转移到胎儿体内。妊娠期糖尿病的特点是蛋白质分解增加，因此预计丝氨酸和甘氨酸周转率会增加。调查计划继续研究正常孕妇、患有胰岛素依赖型糖尿病的孕妇、IUGR胎儿的孕妇、定期剖腹产的妇女和非怀孕对照组。对正常孕妇在整个妊娠过程中进行连续研究。初步数据显示，与怀孕有关的丝氨酸周转率下降。在葡萄糖输注期间，丝氨酸周转率持续下降。这些丝氨酸动力学变化的意义需要进一步评估。