Early Life Socioeconomic Disadvantage and Epigenetic Programming of a Pro-inflammatory Phenotype: a Review of Recent Evidence
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Purpose of Review
A growing body of literature suggests that early life socioeconomic disadvantage (SD) may play a key role in shaping a pro-inflammatory phenotype hypothesized to result from programming of cells of the innate immune system (i.e., monocytes and macrophages) for desensitization to glucocorticoid signaling and exacerbated inflammatory response to immune stimuli, yet understanding of the biologic pathways by which such programming may occur remains limited. The purpose of this review is to discuss the current research supporting the hypothesis that early life SD is associated with a pro-inflammatory phenotype beginning in childhood and highlight recent findings regarding the role that epigenetic programming via DNA methylation (DNAm) specifically, may serve as a biologic mediator of these associations. Gaps in knowledge and recommendations for future research are also discussed.
Findings regarding the association between early life SD and DNAm of genes that may be involved in shaping a pro-inflammatory phenotype are mixed, but lend some support for epigenetic alterations to genes regulating inflammatory processes as a mediator of this association. Studies which integrate data on DNAm, gene expression, and markers of a pro-inflammatory phenotype beginning early in life and over time are ultimately needed to fully understand the role of epigenetic programming in shaping this adverse immune phenotype in those born into socioeconomically disadvantaged environments.
Epigenetic programming of a pro-inflammatory phenotype represents a plausible and understudied pathway by which socioeconomic disparities in chronic disease develop across the lifecourse and are perpetuated across generations.
KeywordsSocioeconomic disadvantage Early life Epigenetic modifications Inflammation
Compliance with Ethical Standards
Conflict of Interest
Amanda M. Simanek and Paul L. Auer each declare no potential conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major Importance
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