Effects of Melatonin as a Novel Antioxidant and Free Radicals Scavenger in Neonatal Sepsis

Abstract

espite advances in antimicrobial therapy and supportive cares, neonatal sepsis is a major cause of death worldwide. In developing countries, many of the more than 14 million deaths of children under five years of age occur during the neonatal period, with sepsis accounting for up to 70% of total mortality for this age group. Newborns and especially preterm infants are probably more prone to oxidative stress than other children and young adults. There are some special reasons for this. These infants very often are exposed to high oxygen concentrations, have infections or inflammation, have reduced antioxidant defense, and have free iron which enhances the Fenton reaction leading to production of highly toxic hydroxyl radicals. Oxygen-derived metabolites, collectively termed reactive oxygen species, are normally produced in aerobic organisms. Oxidative stress is defined as an imbalance between prooxidant and antioxidant forces leading to an overall prooxidant insult. Melatonin is an endogenously produced indolamine principally synthesized in the pineal gland from the neurotransmitter serotonin.Prematurity itself does not hasten the maturation of the neurological network controlling melatonin secretion, Therefore; in premature neonates the melatonin deficiency is more prolonged.