Lenton C, Ali Z, Persaud C, Jackson A A
Institute of Human Nutrition, University of Southampton, UK.
Br J Nutr. 1998 Jul;80(1):51-5. doi: 10.1017/s0007114598001767.
The demand for glycine to satisfy normal growth during early life is considerable and most has to be made endogenously. The extent to which adequate glycine is available can be assessed by measuring the urinary excretion of 5-L-oxoproline. The excretion of 5-L-oxoproline at 6 weeks of age for infants in Trinidad of African, Indian or mixed parentage (398 mumol/mmol creatinine) was significantly greater than for infants born in England of Caucasian parentage (194 mumol/mmol creatinine). There was no relationship between 5-L-oxoproline excretion and either sex or pattern of feeding. There were significant inverse relationships between 5-L-oxoproline/creatinine and birth weight, and head circumference either at birth or 6 weeks of age, suggesting that limited availability of glycine is associated with poorer growth before and after birth. For a group of infants born in England of Indian parentage, excretion of 5-L-oxoproline (155 mumol/mmol creatinine) was not different to infants of Caucasian parentage, but significantly less than infants born in Trinidad. The demonstration that 5-L-oxoproline/creatinine was similar in infants born in England, regardless of parentage, shows that the differences between England and Trinidad are related to environment and are unlikely to be accounted for by genetic differences or ethnicity.
生命早期满足正常生长对甘氨酸的需求量很大，且大部分必须内源性合成。可通过测量5-L-氧代脯氨酸的尿排泄量来评估甘氨酸的充足程度。非洲、印度或混血血统的特立尼达婴儿在6周龄时5-L-氧代脯氨酸的排泄量（398微摩尔/毫摩尔肌酐）显著高于出生在英国的白种人婴儿（194微摩尔/毫摩尔肌酐）。5-L-氧代脯氨酸排泄量与性别或喂养方式均无关联。5-L-氧代脯氨酸/肌酐与出生体重以及出生时或6周龄时的头围之间存在显著负相关，这表明甘氨酸供应有限与出生前后生长较差有关。对于一组出生在英国的印度裔婴儿，5-L-氧代脯氨酸的排泄量（155微摩尔/毫摩尔肌酐）与白种人婴儿无差异，但显著低于出生在特立尼达的婴儿。出生在英国的婴儿，无论其血统如何，5-L-氧代脯氨酸/肌酐相似，这表明英国和特立尼达之间的差异与环境有关，不太可能由基因差异或种族来解释。
