Lifetime maternal stress, fetal sex, and microRNAs in prenatal extracellular vesicles and placenta in relation to children’s internalizing problems

Background Prenatal stress predicts offspring anxiety and depressive disorders and placental microRNA (miRNA) signaling in a sex-specific manner. Methods We prospectively examined associations of miRNAs measured in placental tissue and in extracellular vesicles (EVs) from prenatal maternal blood with preschool Child Behavior Checklist (CBCL) outcomes [Total Problems, Internalizing Problems, Diagnostic and Statistical Manual of Mental Disorders-oriented scales for Anxiety and Affective Problems]. We first used Least Absolute Shrinkage and Selection Operator regressions embedded in a stability selection procedure to identify miRNAs most consistently associated with CBCL outcomes. Then multivariable linear regressions examined all selected miRNAs in relation to each outcome within a single model. Finally, we examined miRNA-CBCL associations stratified by lifetime maternal stress measured prenatally and fetal sex and fit models including a three-way interaction term for stress, sex, and miRNA expression. Results Among miRNAs selected by the machine learning models, miR-330-5p in blood EVs and miR-548aw in placenta emerged as top candidates related to CBCL outcomes. When jointly considering fetal sex and lifetime maternal stress as modifiers, the association between blood miR-330-5p and affective problems was positive in females exposed to low stress (β: 0.73, 95%CI: 0.15, 1.3) but negative in males with high stress exposure (β: -1.64, 95%CI: -3.01, -0.28), pint=0.03. Placental Let-7b expression was negatively associated with total problems among males with high stress exposure (β: -6.58, 95%CI: -12.45, -0.71) but positively associated among males with low stress (β: 3.63, 95%CI: 1.26, 6.01), pint=0.04. Top KEGG pathways included Hippo, FoxO, and PI3K/mTOR signaling. Conclusions Prenatal miRNA signaling may play a role in sex-specific lifetime maternal stress effects on neuropsychological development.