Adverse experiences in the perinatal period have been associated with the methylation of the human glucocorticoid receptor gene (NR3C1) and long-term diseases. We conducted a systematic review on the association between adversities in the perinatal period and DNA methylation in the 1 _F region of the NR3C1 gene in newborns. We explored the MEDLINE, Web of Science, Scopus, Scielo, and Lilacs databases without time or language limitations. Two independent reviewers performed the selection of articles and data extraction. A third participated in the methodological quality assessment and consensus meetings at all stages. Finally, ten studies were selected. Methodological quality was considered moderate in six and low in four. Methylation changes were reported in 41 of the 47 CpG sites of exon 1 _F. Six studies addressed maternal conditions during pregnancy: two reported methylation changes at the same sites (CpG 10, 13, 20, 21 and 47), and four at one or more sites from CpG 35 to 39. Four studies addressed neonatal parameters and morbidities: methylation changes at the same sites 4, 8, 10, 16, 25, and 35 were reported in two. Hypermethylation associated with stressful conditions prevailed. Hypomethylation was more often associated with protective conditions (maternal-foetal attachment during pregnancy, breast milk intake, higher birth weight or Apgar). In conclusion, methylation changes in several sites of the 1 _F region of the NR3C1 gene in newborns and very young infants were associated with perinatal stress, but more robust and comparable results are needed to corroborate site-specific associations.

Aim: To describe NR3C1 exon-1F methylation and cortisol levels in newborns. Materials & methods: Preterm ≤1500 g and full-term infants were included. Samples were collected at birth and at days 5, ... Plain language summary We investigated the methylation of a gene, NR3C1 exon-1F, and cortisol levels in newborns. DNA methylation is a biochemical process that can modify gene activity. In the case... Tweetable abstract Preterm infants have higher rates of NR3C1 gene methylation and cortisol levels at birth than term infants, but this difference reverses over time in the first 3 months of life. ...

This study aims to describe neurological, visual, and auditory findings in children whose mothers had confirmed Zika virus (ZIKV) infection during pregnancy, with most of these children not presenting congenital microcephaly; Methods: an observational, longitudinal, and prospective study was conducted in Rio de Janeiro, Brazil, from March 2015 to January 2017, involving children with in utero exposure to Zika virus, following from birth up to 30 months of age. Results: Of the 2882 pregnant women admitted, 116 had a suspected ZIKV infection, of whom 33 had laboratory confirmation. Only one child presented with congenital microcephaly. Despite this, neurodevelopment delay was observed in 36.4% of children evaluated, radiological abnormalities in 29.1%, auditory abnormalities in 8.3%, and ophthalmological abnormalities in 10%. Conclusions: Newborns of mothers with confirmed ZIKV infection during pregnancy may present with varying degrees of visual, auditory, and neurological impairment, despite the presence of congenital microcephaly.

Background/Objectives: Prematurity is a significant global health concern, often associated with neurodevelopmental challenges. Solute Carrier Family 6 Member 4 (SLC6A4), the gene encoding the serotonin transporter, a key component in serotonin reuptake in the synaptic cleft, plays a key role in stress response and neurodevelopment. Epigenetic regulation of stress-related genes, such as SLC6A4, influences neonatal stress adaptation and developmental outcomes. This study aimed to quantify and compare DNA methylation levels at 13 CpG sites in the promoter region of the SLC6A4 gene between preterm and term neonates at three time points. Methods: A cohort of 46 preterm infants and a cohort of 49 full-term infants were analyzed. Blood samples collected at birth (D0), the fifth day (D5), and the thirtieth day (D30) were used to analyze DNA methylation, using bisulfite conversion and pyrosequencing. Results: Significant differences in SLC6A4 methylation were observed. At D0, CpGs 12 and 13 showed higher methylation in preterm infants. CpG 9 showed lower methylation in preterm infants at D5. Extremely preterm infants had the highest values of methylation at the three time points. Longitudinal mixed-effects analysis revealed distinct temporal patterns between groups. Total and site-specific methylation at CpGs 2, 8, and 9 increased over time in full-term infants, while methylation remained stable over time in very preterm and extremely preterm infants. Conclusions: This study reveals significant differences in SLC6A4 methylation between very preterm, extremely preterm, and full-term infants, highlighting the impact of prematurity and early-life stress on the epigenome. These findings contribute to improving our understanding of the epigenetic mechanisms shaping neurodevelopment and stress adaptation in neonates.

Aim: Promoter methylation of LINE-1 may be affected by prematurity, but there is little evidence in the literature.Materials & methods: Blood from premature and full-term neonates on days 0, 5, 30 and 90 was analyzed for DNA methylation percentage in a promoter region of the LINE-1, after bisulfite conversion and pyrosequencing.Results: Premature infants, as a whole, showed significantly lower methylation percentage at birth, but this difference diminished over time. However, the subgroup of extremely premature (<28 weeks gestational age) had higher methylation percentages, similar to full-term newborns.Conclusion: This research underscores the critical role of prematurity on the methylation pattern of LINE-1. These findings underline the complexity of epigenetic regulation in prematurity and emphasize the need for further studies.