Maternal warmth buffers the effects of low early-life socioeconomic status on pro-inflammatory signaling in adulthood

Abstract

The notion that family support may buffer individuals under adversity from poor outcomes has been theorized to have important implications for mental and physical health, but little is known about the biological mechanisms that explain these links. We hypothesized that adults who grew up in low socioeconomic status (SES) households but who experienced high levels of maternal warmth would be protected from the pro-inflammatory states typically associated with low SES. A total of 53 healthy adults (aged 25-40 years) low in SES early in life were assessed on markers of immune activation and systemic inflammation. Genome-wide transcriptional profiling also was conducted. Low early-life SES individuals who had mothers, who expressed high warmth toward them, exhibited less Toll-like receptor-stimulated production of interleukin 6, and reduced bioinformatic indications of pro-inflammatory transcription factor activity (NF-κB) and immune activating transcription factor activity (AP-1) compared to those who were low in SES early in life but experienced low maternal warmth. To the extent that such effects are causal, they suggest the possibility that the detrimental immunologic effects of low early-life SES environments may be partly diminished through supportive family climates.

Figure 1

Fold differences in the prevalence of transcription factor binding motifs (TFBM) for NF-κB, AP-1, OCT, ELK, GATA, and CREB in promoters of genes differentially expressed among individuals from low early life SES backgrounds who experienced either low or high levels of childhood maternal warmth. For example, for NF-κB, high warmth individuals exhibited a .61 fold difference, or a 39% decrease, in TFBM prevalence compared to high warmth individuals. High warmth individuals also exhibited a 44% decrease in AP-1, a 52% decrease in ELK, a 34% decrease in OCT, and a 13% decrease in GATA TFBM prevalence, along with a 4.4 fold increase in CREB TFBM prevalence, compared to low warmth individuals.

Figure 2

Differences in IL-6 production in response to TLR2/TLR6 stimulation by Zymosan and in response to TLR9 stimulation by ODN for individuals from low early life SES backgrounds who experienced either low or high levels of childhood maternal warmth.