te Braake Frans W J, Schierbeek Henk, Vermes Andras, Huijmans Jan G M, van Goudoever Johannes B
Department of Pediatrics, Division of Neonatology, Erasmus Medical Center-Sophia Children's Hospital, Rotterdam, Netherlands.
Pediatrics. 2009 Nov;124(5):e978-84. doi: 10.1542/peds.2008-2477. Epub 2009 Oct 12.
Our aim was to evaluate whether administration of additional cysteine is safe and stimulates glutathione synthesis in preterm infants in early life.
We conducted a prospective, randomized, clinical trial with infants with birth weights of <1500 g (N = 20). The infants were assigned randomly to receive either a standard dose (45 mg/kg per day) or a high dose (81 mg/kg per day) of cysteine. Intakes of other amino acids were similar, providing a total protein intake of 2.4 g/kg per day in both groups. We recorded base requirements in the first 6 days of life. On postnatal day 2, we conducted a stable isotope study to determine glutathione concentrations and synthesis rates in erythrocytes.
Base requirements were higher in the high-dose cysteine group on days 3, 4, and 5. Despite an 80% increase in cysteine intake, plasma cystine concentrations did not increase. Glutathione concentrations and synthesis rates did not increase with additional cysteine administration.
Administration of a high dose of cysteine (81 mg/kg per day) to preterm infants seems clinically safe but does not stimulate glutathione synthesis, compared with a lower dose (45 mg/kg per day). Further research is required to determine whether there is significant benefit associated with cysteine supplementation.
我们的目的是评估额外补充半胱氨酸对早产婴儿早期是否安全以及是否能刺激谷胱甘肽合成。
我们对出生体重<1500 g的婴儿（N = 20）进行了一项前瞻性、随机临床试验。婴儿被随机分配接受标准剂量（每天45 mg/kg）或高剂量（每天81 mg/kg）的半胱氨酸。两组其他氨基酸的摄入量相似，两组的总蛋白摄入量均为每天2.4 g/kg。我们记录了出生后前6天的基本需求量。在出生后第2天，我们进行了一项稳定同位素研究，以确定红细胞中的谷胱甘肽浓度和合成速率。
高剂量半胱氨酸组在第3、4和5天的基本需求量较高。尽管半胱氨酸摄入量增加了80%，但血浆胱氨酸浓度并未增加。额外补充半胱氨酸后，谷胱甘肽浓度和合成速率并未增加。
与较低剂量（每天45 mg/kg）相比，给早产婴儿高剂量（每天81 mg/kg）补充半胱氨酸在临床上似乎是安全的，但并不能刺激谷胱甘肽合成。需要进一步研究以确定补充半胱氨酸是否有显著益处。
