Parasympathetic nervous activity and CTRA gene expression among healthy young adults in Japan.

Previous research suggests that parasympathetic nervous system (PNS) activity may inhibit the leukocyte Conserved Transcriptional Response to Adversity (CTRA) which has been observed in individuals exposed to prolonged stressors like loneliness, social isolation, and bereavement. Previous PNS-CTRA studies have focused on Western populations, raising questions about the generalizability of these findings across different cultural and ethnic backgrounds. This study examined the relationship between PNS activity (as indexed by heart rate variability; HRV) and CTRA gene expression in young, healthy adults in Japan (n = 26; Mean age = 26; 34.6 % female). In analyses that controlled for demographic and behavioral covariates (including age, sex, ethnicity, smoking, alcohol, and BMI), results showed a significant inverse relationship between HRV and CTRA gene expression (i.e., lower expression of pro-inflammatory genes and elevated expression of Type I interferon response genes). Convergent validation analyses of genome-wide transcription factor activity linked HRV to up-regulation of Interferon Response Factors and down-regulation of NF-κB. These results parallel previous findings from Western samples, confirming that PNS neuro-immune regulation generalizes to an population based in Japan, as part of broader East Asian region and identifying HRV as a useful index for optimizing immune health in diverse populations.