Perfil de metilação no promotor de LINE-1 em recém-nascidos

Abstract

Prematurity, characterized by birth before 37 weeks of gestation, is a global challenge that affects 15 million children around the world every year. In Brazil, around 10% of births are premature, twice as many as in high-income countries, and represent the leading cause of infant mortality. Recent research has studied the relationship between prematurity and epigenetic changes, especially DNA methylation, highlighting the importance of interactions between genetics and environment during fetal development. Adverse factors during pregnancy, such as maternal stress and inadequate nutrition, have been associated with the methylation of specific genes in preterm newborns. It is known that a third of DNA methylation occurs in transposable elements (TE), among them, the Long Interspersed Nuclear Elements (LINE-1), which cover about 18% of the human genome, and their methylation profile can serve as a marker for changes in global DNA methylation. However, studies relating LINE-1 methylation levels to prematurity are scarce. In this context, this study aims to describe the global methylation profile of the LINE-1 promoter region in full-term and preterm newborns at different post-birth moments. This standard may be used as a reference in other studies, contributing to a better understanding of how prematurity can affect the health and development of these children from the point of view of epigenetics. The results obtained showed variations in LINE-1 methylation between term and preterm neonates, with preterm infants having lower methylation at birth, suggesting the influence of prematurity on initial epigenetic configuration. The differences observed between the groups seem to decrease in the first days of life. In addition, there was a tendency for increased LINE-1 methylation over time in preterm newborns, suggesting maturation of the epigenome in the first months of life. In conclusion, the analysis of LINE-1 methylation initiated in this study appears as a new epigenetic and molecular approach with potential impact as a biomarker in the study of prematurity and child development.