Oxidative stress and antioxidant levels in preterm newborns with hyperbilirubinemia

Abstract EN

Background: potentially toxic oxygen free radicals are generated continuously in neonates, especially preterm, under physiological conditions.

The exact pro-oxidant and antioxidant status in neonatal jaundice is still not clear.

Aims : To investigate the relationship between concentrations of nitric oxide (NO), malondialdehyde (MDA), erythrocyte superoxide dismutase enzyme(SOD) and vitamin E and development of hyperbilirubinemia in preterm infants.

Methods : nineteen preterm (gestational age < 37 weeks) infants with indirect hyperbilirubinemia were prospectively recruited in the El-Sahel Teaching Hospital between January and July 2007 comprised patient group.

Nineteen randomly selected healthy preterm infants with age and sex matched without clinical jaundice comprised the control group.

Twenty full term apparently healthy non jaundiced neonates were included [group III).

Plasma malondialdehyde (MDA), nitric oxide (NO) and erythrocyte superoxide dismutase (SOD), vitamin E concentrations were measured within the 1st 24 hours of onset of jaundice.

Results : both MDA and NO concentrations were increased in patient group than the controls (p<0.01).

The SOD and vitamin E were decreased in patient group compared with the control group (p<0.05, P<0.01 respectively).

Total bilirubin didn't correlate to oxidants and antioxidants among the studied groups.

MDA correlated negatively with SOD in patient group.

Conclusions : preterm infants with significant hyperbilirubinemia had increased oxidative stress and decreased antioxidant enzyme activity which may play a role in pathogenesis of hyperbilirubunemia.

Further studies are needed to investigate possible benefits of antioxidants in hyperbilirubinemia.