Lipofuscin; a new lipid peroxidation marker among jaundiced neonates with oxygen free radical induced diseases

ABSTRACT

This study was an attempt to investigate the lipid peroxidation represented by lipofuscin in correlation to some serum antioxidants levels such as vitamins A and E, ceruloplasmin and bilirubin in jaundiced neonates suffering from oxygen free radical induced diseases [ORD] in comparison to a control group. This case-control study was conducted in the NICU, Gynecology and Obstetric Department, Ain Shams University Hospitals in the period from December 1999 to January 2002. This study included 107 jaundiced neonates diagnosed as necrotizing enterocolitis, chronic lung disease, hypoxic-ischemic encephalopathy and neonatal sepsis [ORD Patients group]. They were classified into two subgroups subgroup I, [51 term and preterm babies] with non pathological level of bilirubin i.e not needing interference and subgroup II, [56 newlyborn term and preterm infants] with pathological level of bilirubin i.e needing interference. One hundred and seven apparently healthy neonates were enrolled in this study as a control group. The results of this study revealed that the mean serum levels of vitamins A and E, ceruloplasmin, and hemoglobin were highly significantly decreased while, the mean serum lipofuscin and bilirubin levels were highly significantly increased in the ORD patients group compared to controls [p Similar results were obtained on comparing ORD patients subgroups [subgroup I and subgroup II] to each other and on comparing preterms to fullterms in both subgroups except for serum bilirubin which was significantly lower in preterm Vs fullterm patients. Serum lipofuscin correlated negatively with serum vitamins A and E, ceruloplasmin, and hemoglobin, and positively with total serum bilirubin level. Serum lipofuscin at a level of 94.22 ArU for preterms and 91.47 ArU for full term neonates predicted the occurrence of oxygen free radical diseases with specificity of 95% and sensitivity of 100% in both preterm and fullterm neonates. The positive and negative predictive values were 100% for preterms. On the other h and, the positive and negative predictive values were 96.5% and 100% respectively for fullterm neonates. In conclusion, this study signifies lipofuscin not only as a new lipid peroxidatior marker in newborns with ORD but also, it has higher sensitivity, specificity and predictive values. Moreover, the study revealed that serum bilirubin is markedly increased in patients with oxidative stress indicating its possible role as an antioxidant besides vitamins A and E ceruloplasmin. Hence, it is recommended to further study the significance of lipofuscin as an indicator of the severity as well as the further outcome of ORD