Acute psychosocial stress differentially influences salivary endocrine and immune measures in undergraduate students

Undergraduate students routinely experience acute psychosocial stress when interviewing for post-collegiate employment. While numerous studies have demonstrated that acute stress can increase release of immune-relevant molecules in blood, fewer studies have examined if acute stress also increases immune-relevant molecules into saliva. Saliva, and the biomolecules found in saliva often serve important immune defense roles and can be used to non-invasively screen for many systemic diseases. Therefore, the current study examined saliva concentrations of endocrine and immune molecules following exposure to an acute psychosocial stressor (mock job interview) in undergraduates. Heart rate, blood pressure, salivary cortisol, salivary immunoglobulin-A (S-IgA), and salivary C-reactive protein (S-CRP) were compared in healthy college undergraduates (n=15) before and after completion of the Trier Social Stress Test (TSST). The TSST induced significant increases in heart rate, systolic blood pressure, and salivary cortisol. Additional analyses revealed a non-significant (p=0.1) increase in the level of S-IgA following the TSST. A significant decrease in S-IgA was observed during the recovery period. No change in S-CRP was observed following the TSST. These results suggest that acute stress experienced by undergraduates when interviewing for a job activates the sympathetic nervous system and hypothalamic-pituitary-adrenal axis and that cortisol levels increase in saliva. Stress-induced elevations in cortisol might be responsible for the decreased S-IgA observed following the recovery period. Collectively, these data provide further insight into the interaction between psychosocial stress, endocrine, and immune functioning.