The Study of Oxidative Stress in Preterm New born: Lipid and Protein Peroxidation

Background: The oxidative stress is produced by the harmful effects of free radicals. Several neonatal conditions are correlated with oxidative stress: bronchopulmonary dysplasia, periventricular leucomalacia, retinopathy of prematurity, intraventricular haemorrhage, necrotizing enterocolitis. The harmful effects of free radicals are linked to their capacity to react with polyunsaturated fatty acids of cell membranes, proteins and nucleic acids. Material and method: We conducted a prospective, non-randomized study. In the study group we included 14 preterm neonates with different pathologies: respiratory distress, asphyxia, cerebral haemorrhage. The control group consistedof 13 healthy, late preterm neonates. For all patients, the family's consent was obtained. For the study on oxidative stress we measured the malonildialdehyde (MDA) with Satoh's method and the protein peroxidation was determined spectrophotometrically, as described by Reznick and Packer. For the neonates in the study group, we performed two determinations on the first and third day of life. For control, we performed one measurement on first day of life. The statistical analysis was done with SPSS programme. Results: Five neonates of the study group presented sever asphyxia and ten neonates presented respiratory distress. The median value of MDA in the study group was higher on the third day of life than on the first day(5,12 vs. 4,87 nmol/ml). The protein peroxidation process presented the same behaviour(5,57 vs. 4,91 nmol/ml). The protein peroxidation was significantly higher in the study group than during the control.(p<0.05) Conclusions: The oxidative stress at preterm neonates is more severe when different pathologies are associated, which lead to overproduction of free radicals than in the case of a healthy condition. The knowledge of oxidative stress could be useful to implement antioxidant defences strategies for preterm neonates.