title: Neonatal blood is more resistant to oxidative stress induced by stable nitroxide radicals than adult blood.
abstract: Neonate erythrocytes are more susceptible to oxidizing drugs than adults; however, there are controversial reports in the literature regarding the total antioxidant capacity of neonate blood. Stable nitroxide radicals (NRs) are reduced by blood and some other biological materials to the corresponding hydroxylamines. The kinetics of the nitroxide's disappearance using electron paramagnetic resonance (EPR) spectroscopy, provides useful biochemical and biophysical information about the antioxidant properties of biological systems. In order to investigate the antioxidant properties in the newborn's blood, we applied this novel method on 38 umbilical vein blood samples and 40 healthy adults. The NR, 5-Dimethylaminonaphthalene-1-sulfonyl-4-amino-2,2,6,6,-tetramethyl-piperidine-oxyl (R), was used for this purpose. Ascorbate is the only known natural antioxidant that reduces R. We found that the reduction rates of R in neonate's whole blood are significantly higher (P < 0.001) than the reduction rates of R in adult's whole blood. However, there were no significant differences in the antioxidant capacity between the two groups. Newborn's blood has significantly higher ability to deal with oxidative stress, caused by R, in comparison with adult blood. We suggest that the system that responds to the recycling of ascorbate is more efficient in neonate blood than in adult's blood.
authors: Department of Gynecology and Obstetrics, Soroka University Hospital, Ben-Gurion University of the Negev, Beersheba, Israel.
authors: Tali
authors: T
authors: Silberstein
authors: David
authors: D
authors: Mankuta
authors: Alexander I
authors: AI
authors: Shames
authors: Gertz I
authors: GI
authors: Likhtenshtein
authors: Dan
authors: D
authors: Meyerstein
authors: Naomi
authors: N
authors: Meyerstein
authors: Oshra
authors: O
authors: Saphier
mesh_terms: D000328:Adult; D003619:Dansyl Compounds / Q000493:pharmacokinetics*; D004578:Electron Spin Resonance Spectroscopy; D004912:Erythrocytes / Q000378:metabolism; D005312:Fetal Blood / Q000378:metabolism*; D006400:Hematocrit; D006801:Humans; D007202:Indicators and Reagents / Q000493:pharmacokinetics*; D007231:Infant, Newborn; D008875:Middle Aged; D018384:Oxidative Stress; D014471:Umbilical Veins
chemical_list: C476924:5-dimethylaminonaphthalene-1-sulfonyl-4-amino-2,2,6,6-tetramethyl-1-piperidine-oxyl; D003619:Dansyl Compounds; D007202:Indicators and Reagents