The levels of soluble urokinase plasminogen activator receptor (suPAR) in saliva are influenced by acute stress

•The levels of suPAR in saliva increased following exposure to an acute psychological stressor.•Acute psychological stress also resulted in increased salivary levels of IL-1β, IL-6, TNFα and IL-10.•There were moderate but significant correlations between the post-stress salivary levels of suPAR and IL-1β, TNFα, and IL-6, but not IL-10.•suPAR levels in saliva are stress-reactive and may have a potential application as stress biomarkers in saliva. Although elevations in systemic suPAR levels have been associated with inflammatory conditions and with exposure to life stress and adversity, it is not yet clear whether acute psychological stress influences suPAR levels, either systemically and/or in saliva. The aim of this study was to investigate whether salivary suPAR levels are increased following exposure to acute psychological stress. Healthy subjects, aged 18–40 years, completed a laboratory psychological stressor and provided saliva samples before and after the stress test (60 min apart). Levels of suPAR as well as those of cytokines increased in the post-stress samples (all ps < .001). Baseline and post-stress IL-1β and TNF-α as well as post-stress IL-6 correlated significantly with suPAR (all ps < .01), but IL-10 and baseline IL-6 did not. These results show that suPAR levels in saliva are stress-reactive and suggest a potential application as stress biomarkers in saliva, particularly given the advantage of easily detectable concentrations.