Epigenetic perpetuation of the impact of early life stress on behavior

Maternal perceived stress and green spaces during pregnancy are associated with adult offspring gene (NR3C1 and IGF2/H19) methylation patterns in adulthood: A pilot study

BACKGROUND

Changes in NR3C1 and IGF2/H19 methylation patterns have been associated with behavioural and psychiatric outcomes. Maternal mental state has been associated with offspring NR3C1 promotor and IGF2/H19 imprinting control region (ICR) methylation patterns. However, there is a lack of prospective studies with long-term follow-up.

METHODS

52 mother-offspring pairs were studied from 12 to 22 weeks of pregnancy and offspring was followed-up until 28-29 years-of-age. During pregnancy, mothers filled in a Life Event Scale and a Daily Hassles Scale measuring perceived stress; i.e., appraisal or subjectively experienced severity of impact of important life events and of daily hassles in several life domains during pregnancy, respectively. Green space was quantified around the residence, using high-resolution (1 m2) map data. Saliva and blood samples were obtained from the adult offspring. Absolute DNA methylation levels were determined in blood and saliva on four NR3C1 amplicons, and one IGF2/H19 ICR amplicon using a bisulfite PCR and sequencing method. Linear mixed effect models were used to test the associations between perceived stress and green spaces during pregnancy, and adult offspring methylation patterns.

RESULTS

We found associations between maternal perceived stress during pregnancy and methylation patterns on two out of the four NR3C1 amplicons, measured in blood, from offspring in adulthood, but not with IGF2/H19 methylation. For an interquartile-range (IQR) increase in maternal perceived life event or daily hassles stress scores, absolute methylation levels on several NR3C1 CpG sites were significantly changed (-1.62 % to +5.89 %, p<0.05). Maternal perceived stress scores were not associated with IGF2/H19 methylation, neither in blood nor in saliva. Maternal exposure to green spaces surrounding the residence during the pregnancy was associated with IGF2/H19 ICR methylation (-0.80 % to -1.04 %, p<0.05) in saliva, but not with NR3C1 promotor methylation.

CONCLUSION

We observed significant long-term effects of maternal perceived stress during pregnancy on the methylation patterns of the NR3C1 promotor in offspring well into adulthood. This may imply that maternal psychological distress during pregnancy may influence the regulation of the HPA-axis well into adulthood. Additionally, maternal proximity to green spaces was associated with IGF2/H19 ICR methylation patterns, which is a novel finding.

Evidence for Revising the Adverse Childhood Experiences Screening Tool: a Scoping Review

The relationship between adverse childhood experiences (ACEs) and risky behavior, chronic illness, and premature mortality is well documented. Despite this evidence, screening for ACEs in primary care settings remains limited. Objections to widespread screening include concerns that the original ACE screening tool limited childhood adversities to family and household dysfunction. The purpose of this scoping review is to describe current knowledge for expanding ACEs categories and revising the formatting and scoring of the screening tool. With the assistance of a medical librarian, we used a two-step process to conduct a systematic search in three databases (CINAHL, OVID Medline, PsycINFO). Our aim was to focus on articles that expanded ACE categories and/or revised the scoring or formatting of the ACE tool. Eighteen articles (reporting 19 studies) met criteria. A minimum of two authors extracted the relevant characteristics of the studies independently and conferred to reach agreement. The majority of studies broadened ACEs to include community and systemic categories; three studies revised the formatting or scoring of the ACE tool. Exposure to community violence (ECV) was the most frequently added category (15), followed by economic hardship in childhood (EHC) (13); bullying (10); absence/death of parent or significant others (9); and discrimination (7). This evidence supports the expansion of ACE screening tools for assessment of childhood trauma and timely treatment.