High-dose cysteine administration does not increase synthesis of the antioxidant glutathione preterm infants.

Autor: te Braake FW; Department of Pediatrics, Division of Neonatology, Erasmus Medical Center-Sophia Children's Hospital, Rotterdam, Netherlands., Schierbeek H, Vermes A, Huijmans JG, van Goudoever JB
Jazyk: angličtina
Zdroj: Pediatrics [Pediatrics] 2009 Nov; Vol. 124 (5), pp. e978-84. Date of Electronic Publication: 2009 Oct 12.
DOI: 10.1542/peds.2008-2477
Abstrakt: Objective: Our aim was to evaluate whether administration of additional cysteine is safe and stimulates glutathione synthesis in preterm infants in early life.
Methods: 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.
Results: 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.
Conclusions: 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.
Databáze: MEDLINE