Introduction: Information about oxidative stress in preterms with Respiratory Distress Syndrome (RDS) is defective, so various researches in this area are required, which may open new roads in understanding the pathogenesis of the disease, hence provide additional helpful therapeutic approaches.
Aim: To assess and compare the plasma level of protein carbonyls as a marker for oxidant status and the antioxidant enzymes; Superoxide Dismutase (SOD) and Glutathione Peroxidase (GPx) and the related trace minerals in the form of Copper (Cu), Zinc (Zn) and Selenium (Se) as markers for antioxidant status, in preterms with and without RDS.
Materials and methods: A hospital-based case-control study was conducted on fifty-seven preterm neonates (37 preterms with RDS and 20 preterms without RDS) admitted to neonatal intensive care unit of Qena University Hospitals after approval of the University Hospital Ethical Committee. Plasma protein carbonyls assay was done using commercially available ELISA assay kit. Plasma Cu, Zn, Se, erythrocyte SOD and GPx activities assays were done using commercially available colorimetric assay kits.
Results: Significant higher plasma levels of protein carbonyls and oxidant/antioxidants ratio (protein carbonyls/{SOD+GPx}) with significant lower plasma levels of Zn, Cu, Se, erythrocyte SOD and GPx activities were found in the preterms with RDS when compared with the preterms without RDS (p<0.001 for all measured markers for both groups). In terms of birth weights and gestational ages, they were negatively correlated with both plasma protein carbonyls and oxidant/antioxidants ratio and positively correlated with plasma copper, zinc, selenium, erythrocyte SOD and GPx activities in a statistically significant manner. Non-significant correlations were found between the measured oxidative stress markers and the severity of RDS.
Conclusion: Oxidative stress may have a contributory role in the development of RDS among preterms. Lower birth weight and prematurity may increase the susceptibity to oxidative stress among such patients.
Keywords: Birth weight; Glutathione peroxidase; Prematurity; Superoxide dismutase.