Abstract
Previous research has shown that psychosocial stress is associated with an increased activity of the transcription factor nuclear factor-kappaB (NF-κB), a major inducer of inflammatory genes. While considerable individual variation has been noted, factors contributing to this variation have not been described so far.
Therefore, 29 healthy participants (35.8±12yrs) were exposed to the Trier Social Stress Test. Blood was collected before and repeatedly afterward for determination of NF-κB activity, leukocyte subset numbers, cortisol, norepinephrine, and in vitro-stimulated IL-6 production. Additionally, age, sex, and ratings of perceived chronic and acute stress were assessed.
Regression analyses revealed that older participants showed a lower NF-κB stress response compared to younger adults (β=−.42, p=.026). Higher NF-κB stress responses were associated with lower cortisol stress responses (β=−.37, p=.05), higher pre-stress IL-6 production (β=.38, p=.043), and high chronic in combination with low acute stress, or vice versa (β=−.61, p=.06). Norepinephrine and sex were not associated with NF-κB stress responses (all p⩾.13).
In summary, the present study shows for the first time in human psychosocial stress the negative association of cortisol and NF-κB. This parallels results from in vitro studies. Our finding of lower NF-κB stress responses in older age and in people with high chronic and acute stress might be interpreted as an adaptive dampening of NF-κB activity. In the absence of longitudinal data, however, this interpretation remains speculative.