Phototherapy motivates protein and lipid oxidation in jaundiced term and late term neonates

Hyperbilirubinemia is one of the most important complications encountered in neonatal units. It has been proposed that phototherapy yields oxidative stress. Therefore, this study was undertaken to survey the levels of antioxidant and oxidative stress in the serum neonate before and after phototherapy.
This study was performed on thirty-five healthy, late preterm (> 35 weeks) and term newborn infants from 6-10 days of age who underwent phototherapy due to hyperbilirubinemia (> 240 μmol/L). Infants with a congenital malformation, birth asphyxia, sepsis, those with signs and symptoms suggestive of severe illness, and babies who had received phototherapy before recruitment to the study were excluded. Blood samples were taken to determine total serum bilirubin, the total antioxidant capacity of serum (TAC), malondialdehyde (MDA), advanced oxidation protein products (AOPP) as markers of the intensity of oxidative stress and inflammation with photometric methods, reduced and oxidized glutathione (GSH) by HPLC-UV as well as the ratio of them before and after phototherapy.
The TAC, GSH and, bilirubin levels were significantly lower after phototherapy than before it, although, reversely about levels of MDA, AOPP and oxidized GSH in addition to the ratio of reduced to oxidized GSH (p phototherapy induces oxidative stress and inflammation not only due to inducing of MDA and AOPP but also with reducing of TAS and GSH as well as the ratio of reduced to oxidized GSH. It is suggested that supplementation of antioxidants before phototherapy may reduce oxidative stress in neonatal jaundice. A high positive correlation between total bilirubin and TAC as well as GSH but reversely about MDA and AOPP presented that bilirubin may be an important effect on the total antioxidant activity and oxidative stress.