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Journal Article 2010; 31(3): 319-324 PubMed PMID: 20588236 Citation  Keywords:  Adult, Antioxidants:metabolism, Circadian Rhythm, Female, Fetal Blood:metabolism, Gestational Age, Humans, Hydroxyl Radical:blood, Infant, Newborn, Male, Oxidative Stress:physiology, Parturition:blood, Placenta:physiology, Pregnancy,.   

BACKGROUND: Reactive oxygen species (ROS) may cause peroxydation of lipids, proteins and deoxyribonucleic acids with subsequent cell damage. The hydroxyl radical (OH*) represents a measure of global oxidative stress. Hydroxyl radicals are short-lived; they form an important part of radical chemistry nonetheless. The measure of total antioxidant system (TAS) can give useful information about the extent of defence capable of counteracting the oxidative damage. Pregnancy is an important condition that favors oxidative stress in the fetus. Clinical studies indicate a protective mechanism against O2 toxicity in the human feto-placental unit.

AIM: This study reports the OH* and TAS concentrations in mother and fetus at birth to evaluate the role of the placenta against fetal oxidative stress.

METHODS: Blood samples were collected at delivery from 45 healthy women at term and from their newborns. The maternal and neonatal OH* and TAS concentrations were compared by paired Student t-test.

RESULTS: OH* was higher in maternal blood than in cord blood (573.75+/- 170.0 UCarr/l vs 40.08+/-33.37 UCarr/l) (p<0.01); TAS concentrations did not differ between the two groups (1.11+/-0.09 mmol/l vs 1.17+/-0.12 mmol/l). Multiple regression analyses: maternal and neonatal OH* decreases with maternal age; only maternal TAS and OH* are related to gestational age in a nonlinear fashion. Female infants showed higher values of maternal and neonatal TAS as compared to male infants.

CONCLUSION: TA protective role of the placenta against oxidative damage is in keeping with a large enough gradient of ROS (between mother and fetus) and the passage of TAS from mother to fetus....

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Comparative Study 2004; 25(4): 252-256 PubMed PMID: 15361812 Citation  Keywords:  Analysis of Variance, Animals, Free Radicals:analysis, Hydroxyl Radical:blood, Male, Melatonin:physiology, Nitrogen Oxides:blood, Pain:metabolism, Rats, Rats, Wistar, Reactive Oxygen Species:analysis, Serum:chemistry, Singlet Oxygen:blood, Somatosensory C.   

: The concentrations of ROS were measured in samples of the sensorimotor brain cortex and in the rat blood. We measured the following parameters: The six lines spectra, nitroxide radical, free hydroxyl radical and singleton oxygen. Their concentration was measured under physiological conditions, after the nociceptive stimulation and after the application of melatonin, both in normal and stimulated animals. In the brain cortex only the singleton oxygen decreased after the nociceptive stimulation, whereas the nitroxide radicals and six lines spectra increased. The free hydroxyl radicals did not change significantly. In the blood serum the six lines spectra and nitroxide radical increased, the concentration of the free hydroxyl radicals did not change. Melatonin increased both the hydroxyl and nitroxide radicals. There was a non-significant decrease in the six lines spectra. The estimation of ROS can be used as a tool for detecting metabolic changes and the consequences of different environmental influences, in our case the influence of nociception and melatonin....

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