Acute Interleukin 17A and Cortisol Responses to the Maastricht Acute Stress Test in Healthy Adults

Interleukin-17A (IL-17A) has been implicated in stress- and pain-related inflammation, yet evidence for acute IL-17A stress response in humans remains scarce. This study examined whether the Maastricht Acute Stress Test (MAST) induces changes in circulating IL-17A and how IL-17A dynamics relate to cortisol and subjective stress/pain. Forty-six healthy adults (mean age: 30.50, SD = 12.86 years; 54% female) completed the standardized MAST. Serum IL-17A and cortisol were assessed repeatedly across baseline and recovery. Stress- and pain-related ratings (VAS) and trait questionnaires (e.g., chronic stress, psychological distress, resilience) were completed. There was a significant increase over time in IL-17A and cortisol following the MAST, with an 36 % increase of IL-17A level measured at 105 min post-stressor and cortisol peaking at 10 min post-stressor. IL-17A indices (baseline and AUCi) showed no meaningful associations with cortisol, subjective stress/pain, or psychological traits, whereas cortisol response (AUCi) correlated positively with perceived acute stress and pain. Overall, the MAST produced clear IL-17A and cortisol responses that appeared dissociable in healthy individuals. Future studies should include broader inflammatory panels and clinical or high-stress samples to clarify conditions under which IL-17A covaries with HPA-axis activity and subjective experience.