Maternal early life stress is associated with pro-inflammatory processes during pregnancy

Abstract

Early life stress (ELS) is common in the United States and worldwide, and contributes to the development of psychopathology in individuals with these experiences and their offspring. A growing body of research suggests that early life stress may contribute to adverse health partly through modulation of immune (and particularly inflammatory) responses. Therefore, increased maternal prenatal inflammation has been proposed as a mechanistic pathway by which the observed cross-generational effects of parental early life stress on child neuropsychiatric outcomes may be exerted. We examined associations between early life stress and molecular markers of inflammation (specifically pro-inflammatory gene expression and receptor-mediated transcription factor activity) and a commonly studied circulating marker of inflammation (C-Reactive Protein) in a diverse group of women in or near their third trimester of pregnancy, covarying for age, race/ethnicity, BMI, concurrent infection, concurrent perceived stress, and per capita household income. Mothers who experienced higher levels of early life stress had significantly increased pro-inflammatory (NF-κB) and decreased anti-viral (IRF) transcription factor activity. Transcripts that were up or down regulated in mothers with high ELS were preferentially derived from both CD16+ and CD16- monocytes. Early life stress was not associated with elevated CRP. Taken together, these findings provide preliminary evidence for an association between ELS and a pro-inflammatory transcriptional phenotype during pregnancy that may serve as a mechanistic pathway for cross-generational transmission of the effects of early life stress on mental and physical health.

Keywords: C-Reactive Protein; Conserved transcriptional response to adversity; Cross-generational transmission of adversity; Early life stress; Inflammation; Pregnancy.

Fig. 1.

Bioinformatic analysis suggests increased pro-inflammatory (NF-κB) and decreased anti-viral (IRF) transcription factor activity in mothers with high levels of ELS. Data shown are log2-transformed ratios of transcription factor-binding motifs (TFBMs) for pro-inflammatory and anti-viral transcription factors in the promoters of the 303 genes that showed a greater than 2-fold difference in expression in PBMCs between mothers with high ELS (2 + ACEs) or low ELS (0 ACEs). *p < 0.05. Abbreviations: Interferon Response Factor (IRF); nuclear factor-κB (NF-κB); glucocorticoid receptor (GR); Early Growth Response 1 (EGR1).

Fig. 2.

Results of transcript origin analyses indicate that both transcripts that were up-regulated in mothers with high vs low ELS and transcripts that were down-regulated in mothers with high ELS vs low ELS were preferentially derived from monocytes.